OPENSSL(1) General Commands Manual OPENSSL(1)
NAME
openssl – OpenSSL command line tool
SYNOPSIS
openssl command [command_opts] [command_args]
openssl list-standard-commands | list-message-digest-commands |
list-cipher-commands | list-cipher-algorithms |
list-message-digest-algorithms | list-public-key-algorithms
openssl no-command
DESCRIPTION
OpenSSL is a cryptography toolkit implementing the Transport Layer Security
(TLS v1) network protocol, as well as related cryptography standards.
The openssl program is a command line tool for using the various
cryptography functions of openssl's crypto library from the shell.
The pseudo-commands list-standard-commands, list-message-digest-commands,
and list-cipher-commands output a list (one entry per line) of the names of
all standard commands, message digest commands, or cipher commands,
respectively, that are available in the present openssl utility.
The pseudo-commands list-cipher-algorithms and
list-message-digest-algorithms list all cipher and message digest names,
one entry per line. Aliases are listed as:
from => to
The pseudo-command list-public-key-algorithms lists all supported public
key algorithms.
The pseudo-command no-command tests whether a command of the specified name
is available. If command does not exist, it returns 0 and prints
no-command; otherwise it returns 1 and prints command. In both cases, the
output goes to stdout and nothing is printed to stderr. Additional command
line arguments are always ignored. Since for each cipher there is a
command of the same name, this provides an easy way for shell scripts to
test for the availability of ciphers in the openssl program.
Note: no-command is not able to detect pseudo-commands such as quit,
list-...-commands, or no-command itself.
ASN1PARSE
openssl asn1parse [-i] [-dlimit number] [-dump] [-genconf file]
[-genstr str] [-in file] [-inform der | pem | txt]
[-length number] [-noout] [-offset number] [-oid file]
[-out file] [-strparse offset]
The asn1parse command is a diagnostic utility that can parse ASN.1
structures. It can also be used to extract data from ASN.1 formatted data.
The options are as follows:
-dlimit number
Dump the first number bytes of unknown data in hex form.
-dump Dump unknown data in hex form.
-genconf file, -genstr str
Generate encoded data based on string str, file file, or both,
using the format described in ASN1_generate_nconf(3). If only file
is present then the string is obtained from the default section
using the name “asn1”. The encoded data is passed through the
ASN.1 parser and printed out as though it came from a file; the
contents can thus be examined and written to a file using the -out
option.
-i Indent the output according to the "depth" of the structures.
-in file
The input file to read from, or standard input if not specified.
-inform der | pem | txt
The input format.
-length number
Number of bytes to parse; the default is until end of file.
-noout Do not output the parsed version of the input file.
-offset number
Starting offset to begin parsing; the default is start of file.
-oid file
A file containing additional object identifiers (OIDs). If an OID
(object identifier) is not part of openssl's internal table it will
be represented in numerical form (for example 1.2.3.4).
Each line consists of three columns: the first column is the OID in
numerical format and should be followed by whitespace. The second
column is the "short name", which is a single word followed by
whitespace. The final column is the rest of the line and is the
"long name". asn1parse displays the long name.
-out file
The DER-encoded output file; the default is no encoded output
(useful when combined with -strparse).
-strparse offset
Parse the content octets of the ASN.1 object starting at offset.
This option can be used multiple times to "drill down" into a
nested structure.
CA
openssl ca [-batch] [-cert file] [-config file] [-create_serial]
[-crl_CA_compromise time] [-crl_compromise time]
[-crl_hold instruction] [-crl_reason reason] [-crldays days]
[-crlexts section] [-crlhours hours] [-days arg] [-enddate date]
[-extensions section] [-extfile section] [-gencrl] [-in file]
[-infiles] [-key password] [-keyfile arg] [-keyform pem | der]
[-md arg] [-msie_hack] [-multivalue-rdn] [-name section]
[-noemailDN] [-notext] [-out file] [-outdir dir] [-passin arg]
[-policy arg] [-preserveDN] [-revoke file] [-selfsign]
[-spkac file] [-ss_cert file] [-startdate date] [-status serial]
[-subj arg] [-updatedb] [-utf8] [-verbose]
The ca command is a minimal certificate authority (CA) application. It can
be used to sign certificate requests in a variety of forms and generate
certificate revocation lists (CRLs). It also maintains a text database of
issued certificates and their status.
The options relevant to CAs are as follows:
-batch
Batch mode. In this mode no questions will be asked and all
certificates will be certified automatically.
-cert file
The CA certificate file.
-config file
Specify an alternative configuration file.
-create_serial
If reading the serial from the text file as specified in the
configuration fails, create a new random serial to be used as the
next serial number.
-days arg
The number of days to certify the certificate for.
-enddate date
Set the expiry date. The format of the date is [YY]YYMMDDHHMMSSZ,
with all four year digits required for dates from 2050 onwards.
-extensions section
The section of the configuration file containing certificate
extensions to be added when a certificate is issued (defaults to
x509_extensions unless the -extfile option is used). If no extension
section is present, a V1 certificate is created. If the extension
section is present (even if it is empty), then a V3 certificate is
created. See the x509v3.cnf(5) manual page for details of the
extension section format.
-extfile file
An additional configuration file to read certificate extensions from
(using the default section unless the -extensions option is also
used).
-in file
An input file containing a single certificate request to be signed by
the CA.
-infiles
If present, this should be the last option; all subsequent arguments
are assumed to be the names of files containing certificate requests.
-key password
The password used to encrypt the private key. Since on some systems
the command line arguments are visible, this option should be used
with caution.
-keyfile file
The private key to sign requests with.
-keyform pem | der
Private key file format. The default is pem.
-md alg
The message digest to use. Possible values include md5 and sha1.
This option also applies to CRLs.
-msie_hack
This is a legacy option to make ca work with very old versions of the
IE certificate enrollment control "certenr3". It used
UniversalStrings for almost everything. Since the old control has
various security bugs, its use is strongly discouraged. The newer
control "Xenroll" does not need this option.
-multivalue-rdn
This option causes the -subj argument to be interpreted with full
support for multivalued RDNs, for example
"/DC=org/DC=OpenSSL/DC=users/UID=123456+CN=John Doe". If
-multivalue-rdn is not used, the UID value is set to "123456+CN=John
Doe".
-name section
Specifies the configuration file section to use (overrides default_ca
in the ca section).
-noemailDN
The DN of a certificate can contain the EMAIL field if present in the
request DN, however it is good policy just having the email set into
the altName extension of the certificate. When this option is set,
the EMAIL field is removed from the certificate's subject and set
only in the, eventually present, extensions. The email_in_dn keyword
can be used in the configuration file to enable this behaviour.
-notext
Don't output the text form of a certificate to the output file.
-out file
The output file to output certificates to. The default is standard
output. The certificate details will also be printed out to this
file in PEM format, except that -spkac outputs DER format.
-outdir directory
The directory to output certificates to. The certificate will be
written to a file consisting of the serial number in hex with ".pem"
appended.
-passin arg
The key password source.
-policy arg
Define the CA "policy" to use. The policy section in the
configuration file consists of a set of variables corresponding to
certificate DN fields. The values may be one of "match" (the value
must match the same field in the CA certificate), "supplied" (the
value must be present), or "optional" (the value may be present).
Any fields not mentioned in the policy section are silently deleted,
unless the -preserveDN option is set, but this can be regarded more
of a quirk than intended behaviour.
-preserveDN
Normally, the DN order of a certificate is the same as the order of
the fields in the relevant policy section. When this option is set,
the order is the same as the request. This is largely for
compatibility with the older IE enrollment control which would only
accept certificates if their DNs matched the order of the request.
This is not needed for Xenroll.
-selfsign
Indicates the issued certificates are to be signed with the key the
certificate requests were signed with, given with -keyfile.
Certificate requests signed with a different key are ignored. If
-gencrl, -spkac, or -ss_cert are given, -selfsign is ignored.
A consequence of using -selfsign is that the self-signed certificate
appears among the entries in the certificate database (see the
configuration option database) and uses the same serial number
counter as all other certificates signed with the self-signed
certificate.
-spkac file
A file containing a single Netscape signed public key and challenge,
and additional field values to be signed by the CA. This will
usually come from the KEYGEN tag in an HTML form to create a new
private key. It is, however, possible to create SPKACs using the
spkac utility.
The file should contain the variable SPKAC set to the value of the
SPKAC and also the required DN components as name value pairs. If
it's necessary to include the same component twice, then it can be
preceded by a number and a ‘.’.
-ss_cert file
A single self-signed certificate to be signed by the CA.
-startdate date
Set the start date. The format of the date is [YY]YYMMDDHHMMSSZ,
with all four year digits required for dates from 2050 onwards.
-subj arg
Supersedes the subject name given in the request. The arg must be
formatted as /type0=value0/type1=value1/type2=...; characters may be
escaped by ‘\’ (backslash), no spaces are skipped.
-utf8
Interpret field values read from a terminal or obtained from a
configuration file as UTF-8 strings. By default, they are
interpreted as ASCII.
-verbose
Print extra details about the operations being performed.
The options relevant to CRLs are as follows:
-crl_CA_compromise time
This is the same as -crl_compromise, except the revocation reason is
set to CACompromise.
-crl_compromise time
Set the revocation reason to keyCompromise and the compromise time to
time. time should be in GeneralizedTime format, i.e.
YYYYMMDDHHMMSSZ.
-crl_hold instruction
Set the CRL revocation reason code to certificateHold and the hold
instruction to instruction which must be an OID. Although any OID
can be used, only holdInstructionNone (the use of which is
discouraged by RFC 2459), holdInstructionCallIssuer or
holdInstructionReject will normally be used.
-crl_reason reason
Revocation reason, where reason is one of: unspecified,
keyCompromise, CACompromise, affiliationChanged, superseded,
cessationOfOperation, certificateHold or removeFromCRL. The matching
of reason is case insensitive. Setting any revocation reason will
make the CRL v2. In practice, removeFromCRL is not particularly
useful because it is only used in delta CRLs which are not currently
implemented.
-crldays num
The number of days before the next CRL is due. This is the days from
now to place in the CRL nextUpdate field.
-crlexts section
The section of the configuration file containing CRL extensions to
include. If no CRL extension section is present then a V1 CRL is
created; if the CRL extension section is present (even if it is
empty) then a V2 CRL is created. The CRL extensions specified are
CRL extensions and not CRL entry extensions. It should be noted that
some software can't handle V2 CRLs. See the x509v3.cnf(5) manual
page for details of the extension section format.
-crlhours num
The number of hours before the next CRL is due.
-gencrl
Generate a CRL based on information in the index file.
-revoke file
A file containing a certificate to revoke.
-status serial
Show the status of the certificate with serial number serial.
-updatedb
Update the database index to purge expired certificates.
Many of the options can be set in the ca section of the configuration file
(or in the default section of the configuration file), specified using
default_ca or -name. The options preserve and msie_hack are read directly
from the ca section.
Many of the configuration file options are identical to command line
options. Where the option is present in the configuration file and the
command line, the command line value is used. Where an option is described
as mandatory, then it must be present in the configuration file or the
command line equivalent (if any) used.
certificate
The same as -cert. It gives the file containing the CA certificate.
Mandatory.
copy_extensions
Determines how extensions in certificate requests should be handled.
If set to none or this option is not present, then extensions are
ignored and not copied to the certificate. If set to copy, then any
extensions present in the request that are not already present are
copied to the certificate. If set to copyall, then all extensions in
the request are copied to the certificate: if the extension is
already present in the certificate it is deleted first.
The copy_extensions option should be used with caution. If care is
not taken, it can be a security risk. For example, if a certificate
request contains a basicConstraints extension with CA:TRUE and the
copy_extensions value is set to copyall and the user does not spot
this when the certificate is displayed, then this will hand the
requester a valid CA certificate.
This situation can be avoided by setting copy_extensions to copy and
including basicConstraints with CA:FALSE in the configuration file.
Then if the request contains a basicConstraints extension, it will be
ignored.
The main use of this option is to allow a certificate request to
supply values for certain extensions such as subjectAltName.
crl_extensions
The same as -crlexts.
crlnumber
A text file containing the next CRL number to use in hex. The CRL
number will be inserted in the CRLs only if this file exists. If
this file is present, it must contain a valid CRL number.
database
The text database file to use. Mandatory. This file must be
present, though initially it will be empty.
default_crl_hours, default_crl_days
The same as the -crlhours and -crldays options. These will only be
used if neither command line option is present. At least one of
these must be present to generate a CRL.
default_days
The same as the -days option. The number of days to certify a
certificate for.
default_enddate
The same as the -enddate option. Either this option or default_days
(or the command line equivalents) must be present.
default_md
The same as the -md option. The message digest to use. Mandatory.
default_startdate
The same as the -startdate option. The start date to certify a
certificate for. If not set, the current time is used.
email_in_dn
The same as -noemailDN. If the EMAIL field is to be removed from the
DN of the certificate, simply set this to "no". If not present, the
default is to allow for the EMAIL field in the certificate's DN.
msie_hack
The same as -msie_hack.
name_opt, cert_opt
These options allow the format used to display the certificate
details when asking the user to confirm signing. All the options
supported by the x509 utilities' -nameopt and -certopt switches can
be used here, except that no_signame and no_sigdump are permanently
set and cannot be disabled (this is because the certificate signature
cannot be displayed because the certificate has not been signed at
this point).
For convenience, the value ca_default is accepted by both to produce
a reasonable output.
If neither option is present, the format used in earlier versions of
openssl is used. Use of the old format is strongly discouraged
because it only displays fields mentioned in the policy section,
mishandles multicharacter string types and does not display
extensions.
new_certs_dir
The same as the -outdir command line option. It specifies the
directory where new certificates will be placed. Mandatory.
oid_file
This specifies a file containing additional object identifiers. Each
line of the file should consist of the numerical form of the object
identifier followed by whitespace, then the short name followed by
whitespace and finally the long name.
oid_section
This specifies a section in the configuration file containing extra
object identifiers. Each line should consist of the short name of
the object identifier followed by ‘=’ and the numerical form. The
short and long names are the same when this option is used.
policy
The same as -policy. Mandatory.
preserve
The same as -preserveDN.
private_key
Same as the -keyfile option. The file containing the CA private key.
Mandatory.
serial
A text file containing the next serial number to use in hex.
Mandatory. This file must be present and contain a valid serial
number.
unique_subject
If the value yes is given, the valid certificate entries in the
database must have unique subjects. If the value no is given,
several valid certificate entries may have the exact same subject.
The default value is yes.
x509_extensions
The same as -extensions.
CIPHERS
openssl ciphers [-hVv] [control]
The ciphers command converts the control string from the format documented
in SSL_CTX_set_cipher_list(3) into an ordered SSL cipher suite preference
list. If no control string is specified, the DEFAULT list is printed.
The options are as follows:
-h, -? Print a brief usage message.
-V Verbose. List ciphers with cipher suite code in hex format, cipher
name, and a complete description of protocol version, key exchange,
authentication, encryption, and mac algorithms.
-v Like -V, but without cipher suite codes.
CRL
openssl crl [-CAfile file] [-CApath dir] [-fingerprint] [-hash] [-in file]
[-inform der | pem] [-issuer] [-lastupdate] [-nextupdate]
[-noout] [-out file] [-outform der | pem] [-text]
The crl command processes CRL files in DER or PEM format.
The options are as follows:
-CAfile file
Verify the signature on a CRL by looking up the issuing certificate
in file.
-CApath directory
Verify the signature on a CRL by looking up the issuing certificate
in dir. This directory must be a standard certificate directory,
i.e. a hash of each subject name (using x509 -hash) should be
linked to each certificate.
-fingerprint
Print the CRL fingerprint.
-hash Output a hash of the issuer name. This can be used to look up CRLs
in a directory by issuer name.
-in file
The input file to read from, or standard input if not specified.
-inform der | pem
The input format.
-issuer
Output the issuer name.
-lastupdate
Output the lastUpdate field.
-nextupdate
Output the nextUpdate field.
-noout Do not output the encoded version of the CRL.
-out file
The output file to write to, or standard output if not specified.
-outform der | pem
The output format.
-text Print the CRL in plain text.
CRL2PKCS7
openssl crl2pkcs7 [-certfile file] [-in file] [-inform der | pem] [-nocrl]
[-out file] [-outform der | pem]
The crl2pkcs7 command takes an optional CRL and one or more certificates
and converts them into a PKCS#7 degenerate "certificates only" structure.
The options are as follows:
-certfile file
Add the certificates in PEM file to the PKCS#7 structure. This
option can be used more than once to read certificates from
multiple files.
-in file
Read the CRL from file, or standard input if not specified.
-inform der | pem
The input format.
-nocrl Normally, a CRL is included in the output file. With this option,
no CRL is included in the output file and a CRL is not read from
the input file.
-out file
Write the PKCS#7 structure to file, or standard output if not
specified.
-outform der | pem
The output format.
DGST
openssl dgst [-cd] [-binary] [-digest] [-hex] [-hmac key] [-keyform pem]
[-mac algorithm] [-macopt nm:v] [-out file] [-passin arg]
[-prverify file] [-sign file] [-signature file] [-sigopt nm:v]
[-verify file] [file ...]
The digest functions output the message digest of a supplied file or files
in hexadecimal form. They can also be used for digital signing and
verification.
The options are as follows:
-binary
Output the digest or signature in binary form.
-c Print the digest in two-digit groups separated by colons.
-d Print BIO debugging information.
-digest
Use the specified message digest. The default is MD5. The
available digests can be displayed using openssl
list-message-digest-commands. The following are equivalent:
openssl dgst -md5 and openssl md5.
-hex Digest is to be output as a hex dump. This is the default case for
a "normal" digest as opposed to a digital signature.
-hmac key
Create a hashed MAC using key.
-keyform pem
Specifies the key format to sign the digest with.
-mac algorithm
Create a keyed Message Authentication Code (MAC). The most popular
MAC algorithm is HMAC (hash-based MAC), but there are other MAC
algorithms which are not based on hash. MAC keys and other options
should be set via the -macopt parameter.
-macopt nm:v
Passes options to the MAC algorithm, specified by -mac. The
following options are supported by HMAC:
key:string
Specifies the MAC key as an alphanumeric string (use if the
key contain printable characters only). String length must
conform to any restrictions of the MAC algorithm.
hexkey:string
Specifies the MAC key in hexadecimal form (two hex digits
per byte). Key length must conform to any restrictions of
the MAC algorithm.
-out file
The output file to write to, or standard output if not specified.
-passin arg
The key password source.
-prverify file
Verify the signature using the private key in file. The output is
either "Verification OK" or "Verification Failure".
-sign file
Digitally sign the digest using the private key in file.
-signature file
The actual signature to verify.
-sigopt nm:v
Pass options to the signature algorithm during sign or verify
operations. The names and values of these options are algorithm-
specific.
-verify file
Verify the signature using the public key in file. The output is
either "Verification OK" or "Verification Failure".
file ...
File or files to digest. If no files are specified then standard
input is used.
DHPARAM
openssl dhparam [-2 | -5] [-C] [-check] [-dsaparam] [-in file]
[-inform der | pem] [-noout] [-out file]
[-outform der | pem] [-text] [numbits]
The dhparam command is used to manipulate DH parameter files. Only the
older PKCS#3 DH is supported, not the newer X9.42 DH.
The options are as follows:
-2, -5 The generator to use; 2 is the default. If present, the input file
is ignored and parameters are generated instead.
-C Convert the parameters into C code. The parameters can then be
loaded by calling the get_dhnumbits function.
-check Check the DH parameters.
-dsaparam
Read or create DSA parameters, converted to DH format on output.
Otherwise, "strong" primes (such that (p-1)/2 is also prime) will
be used for DH parameter generation.
DH parameter generation with the -dsaparam option is much faster,
and the recommended exponent length is shorter, which makes DH key
exchange more efficient. Beware that with such DSA-style DH
parameters, a fresh DH key should be created for each use to avoid
small-subgroup attacks that may be possible otherwise.
-in file
The input file to read from, or standard input if not specified.
-inform der | pem
The input format.
-noout Do not output the encoded version of the parameters.
-out file
The output file to write to, or standard output if not specified.
-outform der | pem
The output format.
-text Print the DH parameters in plain text.
numbits
Generate a parameter set of size numbits. It must be the last
option. If not present, a value of 2048 is used. If this value is
present, the input file is ignored and parameters are generated
instead.
DSA
openssl dsa [-aes128 | -aes192 | -aes256 | -des | -des3] [-in file]
[-inform der | pem] [-modulus] [-noout] [-out file]
[-outform der | pem] [-passin arg] [-passout arg] [-pubin]
[-pubout] [-text]
The dsa command processes DSA keys. They can be converted between various
forms and their components printed out.
Note: This command uses the traditional SSLeay compatible format for
private key encryption: newer applications should use the more secure
PKCS#8 format using the pkcs8 command.
The options are as follows:
-aes128 | -aes192 | -aes256 | -des | -des3
Encrypt the private key with the AES, DES, or the triple DES
ciphers, respectively, before outputting it. A pass phrase is
prompted for. If none of these options are specified, the key is
written in plain text. This means that using the dsa utility to
read an encrypted key with no encryption option can be used to
remove the pass phrase from a key, or by setting the encryption
options it can be used to add or change the pass phrase. These
options can only be used with PEM format output files.
-in file
The input file to read from, or standard input if not specified.
If the key is encrypted, a pass phrase will be prompted for.
-inform der | pem
The input format.
-modulus
Print the value of the public key component of the key.
-noout Do not output the encoded version of the key.
-out file
The output file to write to, or standard output if not specified.
If any encryption options are set then a pass phrase will be
prompted for.
-outform der | pem
The output format.
-passin arg
The key password source.
-passout arg
The output file password source.
-pubin Read in a public key, not a private key.
-pubout
Output a public key, not a private key. Automatically set if the
input is a public key.
-text Print the public/private key in plain text.
DSAPARAM
openssl dsaparam [-C] [-genkey] [-in file] [-inform der | pem] [-noout]
[-out file] [-outform der | pem] [-text] [numbits]
The dsaparam command is used to manipulate or generate DSA parameter files.
The options are as follows:
-C Convert the parameters into C code. The parameters can then be
loaded by calling the get_dsaXXX function.
-genkey
Generate a DSA key either using the specified or generated
parameters.
-in file
The input file to read from, or standard input if not specified.
If the numbits parameter is included, then this option is ignored.
-inform der | pem
The input format.
-noout Do not output the encoded version of the parameters.
-out file
The output file to write to, or standard output if not specified.
-outform der | pem
The output format.
-text Print the DSA parameters in plain text.
numbits
Generate a parameter set of size numbits. If this option is
included, the input file is ignored.
EC
openssl ec [-conv_form arg] [-des] [-des3] [-in file] [-inform der | pem]
[-noout] [-out file] [-outform der | pem] [-param_enc arg]
[-param_out] [-passin arg] [-passout arg] [-pubin] [-pubout]
[-text]
The ec command processes EC keys. They can be converted between various
forms and their components printed out. openssl uses the private key
format specified in “SEC 1: Elliptic Curve Cryptography”
(http://www.secg.org/). To convert an EC private key into the PKCS#8
private key format use the pkcs8 command.
The options are as follows:
-conv_form arg
Specify how the points on the elliptic curve are converted into
octet strings. Possible values are: compressed (the default),
uncompressed, and hybrid. For more information regarding the point
conversion forms see the X9.62 standard. Note: Due to patent
issues the compressed option is disabled by default for binary
curves and can be enabled by defining the preprocessor macro
OPENSSL_EC_BIN_PT_COMP at compile time.
-des | -des3
Encrypt the private key with DES, triple DES, or any other cipher
supported by openssl. A pass phrase is prompted for. If none of
these options is specified the key is written in plain text. This
means that using the ec utility to read in an encrypted key with no
encryption option can be used to remove the pass phrase from a key,
or by setting the encryption options it can be used to add or
change the pass phrase. These options can only be used with PEM
format output files.
-in file
The input file to read a key from, or standard input if not
specified. If the key is encrypted a pass phrase will be prompted
for.
-inform der | pem
The input format.
-noout Do not output the encoded version of the key.
-out file
The output filename to write to, or standard output if not
specified. If any encryption options are set then a pass phrase
will be prompted for.
-outform der | pem
The output format.
-param_enc arg
Specify how the elliptic curve parameters are encoded. Possible
value are: named_curve, i.e. the EC parameters are specified by an
OID; or explicit, where the EC parameters are explicitly given (see
RFC 3279 for the definition of the EC parameter structures). The
default value is named_curve. Note: the implicitlyCA alternative,
as specified in RFC 3279, is currently not implemented.
-passin arg
The key password source.
-passout arg
The output file password source.
-pubin Read in a public key, not a private key.
-pubout
Output a public key, not a private key. Automatically set if the
input is a public key.
-text Print the public/private key in plain text.
ECPARAM
openssl ecparam [-C] [-check] [-conv_form arg] [-genkey] [-in file]
[-inform der | pem] [-list_curves] [-name arg] [-no_seed]
[-noout] [-out file] [-outform der | pem] [-param_enc arg]
[-text]
The ecparam command is used to manipulate or generate EC parameter files.
openssl is not able to generate new groups so ecparam can only create EC
parameters from known (named) curves.
The options are as follows:
-C Convert the EC parameters into C code. The parameters can then be
loaded by calling the get_ec_group_XXX function.
-check Validate the elliptic curve parameters.
-conv_form arg
Specify how the points on the elliptic curve are converted into
octet strings. Possible values are: compressed (the default),
uncompressed, and hybrid. For more information regarding the point
conversion forms see the X9.62 standard. Note: Due to patent
issues the compressed option is disabled by default for binary
curves and can be enabled by defining the preprocessor macro
OPENSSL_EC_BIN_PT_COMP at compile time.
-genkey
Generate an EC private key using the specified parameters.
-in file
The input file to read from, or standard input if not specified.
-inform der | pem
The input format.
-list_curves
Print a list of all currently implemented EC parameter names and
exit.
-name arg
Use the EC parameters with the specified "short" name.
-no_seed
Do not include the seed for the parameter generation in the
ECParameters structure (see RFC 3279).
-noout Do not output the encoded version of the parameters.
-out file
The output file to write to, or standard output if not specified.
-outform der | pem
The output format.
-param_enc arg
Specify how the elliptic curve parameters are encoded. Possible
value are: named_curve, i.e. the EC parameters are specified by an
OID, or explicit, where the EC parameters are explicitly given (see
RFC 3279 for the definition of the EC parameter structures). The
default value is named_curve. Note: the implicitlyCA alternative,
as specified in RFC 3279, is currently not implemented.
-text Print the EC parameters in plain text.
ENC
openssl enc -ciphername [-AadePp] [-base64] [-bufsize number] [-debug]
[-in file] [-iv IV] [-K key] [-k password] [-kfile file]
[-md digest] [-none] [-nopad] [-nosalt] [-out file] [-pass arg]
[-S salt] [-salt]
The symmetric cipher commands allow data to be encrypted or decrypted using
various block and stream ciphers using keys based on passwords or
explicitly provided. Base64 encoding or decoding can also be performed
either by itself or in addition to the encryption or decryption. The
program can be called either as openssl ciphername or openssl enc
-ciphername.
Some of the ciphers do not have large keys and others have security
implications if not used correctly. All the block ciphers normally use
PKCS#5 padding, also known as standard block padding. If padding is
disabled, the input data must be a multiple of the cipher block length.
The options are as follows:
-A If the -a option is set, then base64 process the data on one line.
-a, -base64
Base64 process the data. This means that if encryption is taking
place, the data is base64-encoded after encryption. If decryption
is set, the input data is base64-decoded before being decrypted.
-bufsize number
Set the buffer size for I/O.
-d Decrypt the input data.
-debug Debug the BIOs used for I/O.
-e Encrypt the input data. This is the default.
-in file
The input file to read from, or standard input if not specified.
-iv IV The actual IV (initialisation vector) to use: this must be
represented as a string comprised only of hex digits. When only
the key is specified using the -K option, the IV must explicitly be
defined. When a password is being specified using one of the other
options, the IV is generated from this password.
-K key The actual key to use: this must be represented as a string
comprised only of hex digits. If only the key is specified, the IV
must also be specified using the -iv option. When both a key and a
password are specified, the key given with the -K option will be
used and the IV generated from the password will be taken. It
probably does not make much sense to specify both key and password.
-k password
The password to derive the key from. Superseded by the -pass
option.
-kfile file
Read the password to derive the key from the first line of file.
Superseded by the -pass option.
-md digest
Use digest to create a key from a pass phrase. digest may be one
of md5 or sha1.
-none Use NULL cipher (no encryption or decryption of input).
-nopad Disable standard block padding.
-nosalt
Don't use a salt in the key derivation routines. This option
should never be used since it makes it possible to perform
efficient dictionary attacks on the password and to attack stream
cipher encrypted data.
-out file
The output file to write to, or standard output if not specified.
-P Print out the salt, key, and IV used, then immediately exit; don't
do any encryption or decryption.
-p Print out the salt, key, and IV used.
-pass arg
The password source.
-S salt
The actual salt to use: this must be represented as a string
comprised only of hex digits.
-salt Use a salt in the key derivation routines (the default). When the
salt is being used the first eight bytes of the encrypted data are
reserved for the salt: it is randomly generated when encrypting a
file and read from the encrypted file when it is decrypted.
ERRSTR
openssl errstr [-stats] errno ...
The errstr command performs error number to error string conversion,
generating a human-readable string representing the error code errno. The
string is obtained through the ERR_error_string_n(3) function and has the
following format:
error:[error code]:[library name]:[function name]:[reason string]
[error code] is an 8-digit hexadecimal number. The remaining fields
[library name], [function name], and [reason string] are all ASCII text.
The options are as follows:
-stats Print debugging statistics about various aspects of the hash table.
GENDSA
openssl gendsa [-aes128 | -aes192 | -aes256 | -des | -des3] [-out file]
[paramfile]
The gendsa command generates a DSA private key from a DSA parameter file
(typically generated by the openssl dsaparam command). DSA key generation
is little more than random number generation so it is much quicker than,
for example, RSA key generation.
The options are as follows:
-aes128 | -aes192 | -aes256 | -des | -des3
Encrypt the private key with the AES, DES, or the triple DES
ciphers, respectively, before outputting it. A pass phrase is
prompted for. If none of these options are specified, no
encryption is used.
-out file
The output file to write to, or standard output if not specified.
paramfile
Specify the DSA parameter file to use. The parameters in this file
determine the size of the private key.
GENPKEY
openssl genpkey [-algorithm alg] [cipher] [-genparam] [-out file]
[-outform der | pem] [-paramfile file] [-pass arg]
[-pkeyopt opt:value] [-text]
The genpkey command generates private keys. The use of this program is
encouraged over the algorithm specific utilities because additional
algorithm options can be used.
The options are as follows:
-algorithm alg
The public key algorithm to use, such as RSA, DSA, or DH. This
option must precede any -pkeyopt options. The options -paramfile
and -algorithm are mutually exclusive.
cipher Encrypt the private key with the supplied cipher. Any algorithm
name accepted by EVP_get_cipherbyname(3) is acceptable.
-genparam
Generate a set of parameters instead of a private key. This option
must precede any -algorithm, -paramfile, or -pkeyopt options.
-out file
The output file to write to, or standard output if not specified.
-outform der | pem
The output format.
-paramfile file
Some public key algorithms generate a private key based on a set of
parameters, which can be supplied using this option. If this
option is used the public key algorithm used is determined by the
parameters. This option must precede any -pkeyopt options. The
options -paramfile and -algorithm are mutually exclusive.
-pass arg
The output file password source.
-pkeyopt opt:value
Set the public key algorithm option opt to value, as follows:
rsa_keygen_bits:numbits
(RSA) The number of bits in the generated key. The
default is 2048.
rsa_keygen_pubexp:value
(RSA) The RSA public exponent value. This can be a
large decimal or hexadecimal value if preceded by 0x.
The default is 65537.
dsa_paramgen_bits:numbits
(DSA) The number of bits in the generated parameters.
The default is 1024.
dh_paramgen_prime_len:numbits
(DH) The number of bits in the prime parameter p.
dh_paramgen_generator:value
(DH) The value to use for the generator g.
ec_paramgen_curve:curve
(EC) The EC curve to use.
-text Print the private/public key in plain text.
GENRSA
openssl genrsa [-3 | -f4] [-aes128 | -aes192 | -aes256 | -des | -des3]
[-out file] [-passout arg] [numbits]
The genrsa command generates an RSA private key, which essentially involves
the generation of two prime numbers. When generating the key, various
symbols will be output to indicate the progress of the generation. A ‘.’
represents each number which has passed an initial sieve test; ‘+’ means a
number has passed a single round of the Miller-Rabin primality test. A
newline means that the number has passed all the prime tests (the actual
number depends on the key size).
The options are as follows:
-3 | -f4
The public exponent to use, either 3 or 65537. The default is
65537.
-aes128 | -aes192 | -aes256 | -des | -des3
Encrypt the private key with the AES, DES, or the triple DES
ciphers, respectively, before outputting it. If none of these
options are specified, no encryption is used. If encryption is
used, a pass phrase is prompted for, if it is not supplied via the
-passout option.
-out file
The output file to write to, or standard output if not specified.
-passout arg
The output file password source.
numbits
The size of the private key to generate in bits. This must be the
last option specified. The default is 2048.
NSEQ
openssl nseq [-in file] [-out file] [-toseq]
The nseq command takes a file containing a Netscape certificate sequence
(an alternative to the standard PKCS#7 format) and prints out the
certificates contained in it, or takes a file of certificates and converts
it into a Netscape certificate sequence.
The options are as follows:
-in file
The input file to read from, or standard input if not specified.
-out file
The output file to write to, or standard output if not specified.
-toseq Normally, a Netscape certificate sequence will be input and the
output is the certificates contained in it. With the -toseq option
the situation is reversed: a Netscape certificate sequence is
created from a file of certificates.
OCSP
openssl ocsp [-CA file] [-CAfile file] [-CApath directory] [-cert file]
[-dgst alg] [-host hostname:port] [-index indexfile]
[-issuer file] [-ndays days] [-nmin minutes] [-no_cert_checks]
[-no_cert_verify] [-no_certs] [-no_chain] [-no_intern]
[-no_nonce] [-no_signature_verify] [-nonce] [-noverify]
[-nrequest number] [-out file] [-path path] [-port portnum]
[-req_text] [-reqin file] [-reqout file] [-resp_key_id]
[-resp_no_certs] [-resp_text] [-respin file] [-respout file]
[-rkey file] [-rother file] [-rsigner file] [-serial number]
[-sign_other file] [-signer file] [-signkey file]
[-status_age age] [-text] [-trust_other] [-url responder_url]
[-VAfile file] [-validity_period nsec] [-verify_other file]
The Online Certificate Status Protocol (OCSP) enables applications to
determine the (revocation) state of an identified certificate (RFC 2560).
The ocsp command performs many common OCSP tasks. It can be used to print
out requests and responses, create requests and send queries to an OCSP
responder, and behave like a mini OCSP server itself.
The options are as follows:
-CAfile file, -CApath directory
A file or path containing trusted CA certificates, used to verify
the signature on the OCSP response.
-cert file
Add the certificate file to the request. The issuer certificate is
taken from the previous -issuer option, or an error occurs if no
issuer certificate is specified.
-dgst alg
Use the digest algorithm alg for certificate identification in the
OCSP request. By default SHA-1 is used.
-host hostname:port, -path path
Send the OCSP request to hostname on port. -path specifies the
HTTP path name to use, or / by default.
-issuer file
The current issuer certificate, in PEM format. Can be used
multiple times and must come before any -cert options.
-no_cert_checks
Don't perform any additional checks on the OCSP response signer's
certificate. That is, do not make any checks to see if the
signer's certificate is authorised to provide the necessary status
information: as a result this option should only be used for
testing purposes.
-no_cert_verify
Don't verify the OCSP response signer's certificate at all. Since
this option allows the OCSP response to be signed by any
certificate, it should only be used for testing purposes.
-no_certs
Don't include any certificates in the signed request.
-no_chain
Do not use certificates in the response as additional untrusted CA
certificates.
-no_intern
Ignore certificates contained in the OCSP response when searching
for the signer's certificate. The signer's certificate must be
specified with either the -verify_other or -VAfile options.
-no_signature_verify
Don't check the signature on the OCSP response. Since this option
tolerates invalid signatures on OCSP responses, it will normally
only be used for testing purposes.
-nonce, -no_nonce
Add an OCSP nonce extension to a request, or disable an OCSP nonce
addition. Normally, if an OCSP request is input using the -respin
option no nonce is added: using the -nonce option will force the
addition of a nonce. If an OCSP request is being created (using
the -cert and -serial options) a nonce is automatically added;
specifying -no_nonce overrides this.
-noverify
Don't attempt to verify the OCSP response signature or the nonce
values. This is normally only be used for debugging since it
disables all verification of the responder's certificate.
-out file
Specify the output file to write to, or standard output if not
specified.
-req_text, -resp_text, -text
Print out the text form of the OCSP request, response, or both,
respectively.
-reqin file, -respin file
Read an OCSP request or response file from file. These options are
ignored if an OCSP request or response creation is implied by other
options (for example with the -serial, -cert, and -host options).
-reqout file, -respout file
Write out the DER-encoded certificate request or response to file.
-serial num
Same as the -cert option except the certificate with serial number
num is added to the request. The serial number is interpreted as a
decimal integer unless preceded by ‘0x’. Negative integers can
also be specified by preceding the value with a minus sign.
-sign_other file
Additional certificates to include in the signed request.
-signer file, -signkey file
Sign the OCSP request using the certificate specified in the
-signer option and the private key specified by the -signkey
option. If the -signkey option is not present, then the private
key is read from the same file as the certificate. If neither
option is specified, the OCSP request is not signed.
-trust_other
The certificates specified by the -verify_other option should be
explicitly trusted and no additional checks will be performed on
them. This is useful when the complete responder certificate chain
is not available or trusting a root CA is not appropriate.
-url responder_url
Specify the responder URL. Both HTTP and HTTPS (SSL/TLS) URLs can
be specified.
-VAfile file
A file containing explicitly trusted responder certificates.
Equivalent to the -verify_other and -trust_other options.
-validity_period nsec, -status_age age
The range of times, in seconds, which will be tolerated in an OCSP
response. Each certificate status response includes a notBefore
time and an optional notAfter time. The current time should fall
between these two values, but the interval between the two times
may be only a few seconds. In practice the OCSP responder and
clients' clocks may not be precisely synchronised and so such a
check may fail. To avoid this the -validity_period option can be
used to specify an acceptable error range in seconds, the default
value being 5 minutes.
If the notAfter time is omitted from a response, it means that new
status information is immediately available. In this case the age
of the notBefore field is checked to see it is not older than age
seconds old. By default, this additional check is not performed.
-verify_other file
A file containing additional certificates to search when attempting
to locate the OCSP response signing certificate. Some responders
omit the actual signer's certificate from the response, so this can
be used to supply the necessary certificate.
The options for the OCSP server are as follows:
-CA file
CA certificate corresponding to the revocation information in
indexfile.
-index indexfile
indexfile is a text index file in ca format containing certificate
revocation information.
If this option is specified, ocsp is in responder mode, otherwise it
is in client mode. The requests the responder processes can be
either specified on the command line (using the -issuer and -serial
options), supplied in a file (using the -respin option), or via
external OCSP clients (if port or url is specified).
If this option is present, then the -CA and -rsigner options must
also be present.
-nmin minutes, -ndays days
Number of minutes or days when fresh revocation information is
available: used in the nextUpdate field. If neither option is
present, the nextUpdate field is omitted, meaning fresh revocation
information is immediately available.
-nrequest number
Exit after receiving number requests (the default is unlimited).
-port portnum
Port to listen for OCSP requests on. May also be specified using the
-url option.
-resp_key_id
Identify the signer certificate using the key ID; the default is to
use the subject name.
-resp_no_certs
Don't include any certificates in the OCSP response.
-rkey file
The private key to sign OCSP responses with; if not present, the file
specified in the -rsigner option is used.
-rother file
Additional certificates to include in the OCSP response.
-rsigner file
The certificate to sign OCSP responses with.
Initially the OCSP responder certificate is located and the signature on
the OCSP request checked using the responder certificate's public key.
Then a normal certificate verify is performed on the OCSP responder
certificate building up a certificate chain in the process. The locations
of the trusted certificates used to build the chain can be specified by the
-CAfile and -CApath options or they will be looked for in the standard
openssl certificates directory.
If the initial verify fails, the OCSP verify process halts with an error.
Otherwise the issuing CA certificate in the request is compared to the OCSP
responder certificate: if there is a match then the OCSP verify succeeds.
Otherwise the OCSP responder certificate's CA is checked against the
issuing CA certificate in the request. If there is a match and the
OCSPSigning extended key usage is present in the OCSP responder
certificate, then the OCSP verify succeeds.
Otherwise the root CA of the OCSP responder's CA is checked to see if it is
trusted for OCSP signing. If it is, the OCSP verify succeeds.
If none of these checks is successful, the OCSP verify fails. What this
effectively means is that if the OCSP responder certificate is authorised
directly by the CA it is issuing revocation information about (and it is
correctly configured), then verification will succeed.
If the OCSP responder is a global responder, which can give details about
multiple CAs and has its own separate certificate chain, then its root CA
can be trusted for OCSP signing. Alternatively, the responder certificate
itself can be explicitly trusted with the -VAfile option.
PASSWD
openssl passwd [-1 | -apr1 | -crypt] [-in file] [-noverify] [-quiet]
[-reverse] [-salt string] [-stdin] [-table] [password]
The passwd command computes the hash of a password.
The options are as follows:
-1 Use the MD5 based BSD password algorithm "1".
-apr1 Use the "apr1" algorithm (Apache variant of the BSD algorithm).
-crypt Use the "crypt" algorithm (the default).
-in file
Read passwords from file.
-noverify
Don't verify when reading a password from the terminal.
-quiet Don't output warnings when passwords given on the command line are
truncated.
-reverse
Switch table columns. This only makes sense in conjunction with
the -table option.
-salt string
Use the salt specified by string. When reading a password from the
terminal, this implies -noverify.
-stdin Read passwords from standard input.
-table In the output list, prepend the cleartext password and a TAB
character to each password hash.
PKCS7
openssl pkcs7 [-in file] [-inform der | pem] [-noout] [-out file]
[-outform der | pem] [-print_certs] [-text]
The pkcs7 command processes PKCS#7 files in DER or PEM format. The PKCS#7
routines only understand PKCS#7 v 1.5 as specified in RFC 2315.
The options are as follows:
-in file
The input file to read from, or standard input if not specified.
-inform der | pem
The input format.
-noout Don't output the encoded version of the PKCS#7 structure (or
certificates if -print_certs is set).
-out file
The output to write to, or standard output if not specified.
-outform der | pem
The output format.
-print_certs
Print any certificates or CRLs contained in the file, preceded by
their subject and issuer names in a one-line format.
-text Print certificate details in full rather than just subject and
issuer names.
PKCS8
openssl pkcs8 [-in file] [-inform der | pem] [-nocrypt] [-noiter]
[-out file] [-outform der | pem] [-passin arg] [-passout arg]
[-topk8] [-v1 alg] [-v2 alg]
The pkcs8 command processes private keys (both encrypted and unencrypted)
in PKCS#8 format with a variety of PKCS#5 (v1.5 and v2.0) and PKCS#12
algorithms. The default encryption is only 56 bits; keys encrypted using
PKCS#5 v2.0 algorithms and high iteration counts are more secure.
The options are as follows:
-in file
The input file to read from, or standard input if not specified.
If the key is encrypted, a pass phrase will be prompted for.
-inform der | pem
The input format.
-nocrypt
Generate an unencrypted PrivateKeyInfo structure. This option does
not encrypt private keys at all and should only be used when
absolutely necessary.
-noiter
Use an iteration count of 1. See the PKCS12 section below for a
detailed explanation of this option.
-out file
The output file to write to, or standard output if none is
specified. If any encryption options are set, a pass phrase will
be prompted for.
-outform der | pem
The output format.
-passin arg
The key password source.
-passout arg
The output file password source.
-topk8 Read a traditional format private key and write a PKCS#8 format
key.
-v1 alg
Specify a PKCS#5 v1.5 or PKCS#12 algorithm to use.
PBE-MD5-DES
56-bit DES.
PBE-SHA1-RC2-64 | PBE-MD5-RC2-64 | PBE-SHA1-DES
64-bit RC2 or 56-bit DES.
PBE-SHA1-RC4-128 | PBE-SHA1-RC4-40 | PBE-SHA1-3DES
PBE-SHA1-2DES | PBE-SHA1-RC2-128 | PBE-SHA1-RC2-40
PKCS#12 password-based encryption algorithm, which allow
strong encryption algorithms like triple DES or 128-bit RC2.
-v2 alg
Use PKCS#5 v2.0 algorithms. Supports algorithms such as 168-bit
triple DES or 128-bit RC2, however not many implementations support
PKCS#5 v2.0 yet (if using private keys with openssl this doesn't
matter).
alg is the encryption algorithm to use; valid values include des,
des3, and rc2. It is recommended that des3 is used.
PKCS12
openssl pkcs12 [-aes128 | -aes192 | -aes256 | -des | -des3] [-cacerts]
[-CAfile file] [-caname name] [-CApath directory]
[-certfile file] [-certpbe alg] [-chain] [-clcerts]
[-CSP name] [-descert] [-export] [-in file] [-info]
[-inkey file] [-keyex] [-keypbe alg] [-keysig] [-macalg alg]
[-maciter] [-name name] [-nocerts] [-nodes] [-noiter]
[-nokeys] [-nomac] [-nomaciter] [-nomacver] [-noout]
[-out file] [-passin arg] [-passout arg] [-twopass]
The pkcs12 command allows PKCS#12 files (sometimes referred to as PFX
files) to be created and parsed. By default, a PKCS#12 file is parsed; a
PKCS#12 file can be created by using the -export option.
The options for parsing a PKCS12 file are as follows:
-aes128 | -aes192 | -aes256 | -des | -des3
Encrypt private keys using AES, DES, or triple DES, respectively.
The default is triple DES.
-cacerts
Only output CA certificates (not client certificates).
-clcerts
Only output client certificates (not CA certificates).
-in file
The input file to read from, or standard input if not specified.
-info
Output additional information about the PKCS#12 file structure,
algorithms used, and iteration counts.
-nocerts
Do not output certificates.
-nodes
Do not encrypt private keys.
-nokeys
Do not output private keys.
-nomacver
Do not attempt to verify the integrity MAC before reading the file.
-noout
Do not output the keys and certificates to the output file version of
the PKCS#12 file.
-out file
The output file to write to, or standard output if not specified.
-passin arg
The key password source.
-passout arg
The output file password source.
-twopass
Prompt for separate integrity and encryption passwords: most software
always assumes these are the same so this option will render such
PKCS#12 files unreadable.
The options for PKCS12 file creation are as follows:
-CAfile file
CA storage as a file.
-CApath directory
CA storage as a directory. The directory must be a standard
certificate directory: that is, a hash of each subject name (using
x509 -hash) should be linked to each certificate.
-caname name
Specify the "friendly name" for other certificates. May be used
multiple times to specify names for all certificates in the order
they appear.
-certfile file
A file to read additional certificates from.
-certpbe alg, -keypbe alg
Specify the algorithm used to encrypt the private key and
certificates to be selected. Any PKCS#5 v1.5 or PKCS#12 PBE
algorithm name can be used. If a cipher name (as output by the
list-cipher-algorithms command) is specified then it is used with
PKCS#5 v2.0. For interoperability reasons it is advisable to only
use PKCS#12 algorithms.
-chain
Include the entire certificate chain of the user certificate. The
standard CA store is used for this search. If the search fails, it
is considered a fatal error.
-CSP name
Write name as a Microsoft CSP name.
-descert
Encrypt the certificate using triple DES; this may render the PKCS#12
file unreadable by some "export grade" software. By default, the
private key is encrypted using triple DES and the certificate using
40-bit RC2.
-export
Create a PKCS#12 file (rather than parsing one).
-in file
The input file to read from, or standard input if not specified. The
order doesn't matter but one private key and its corresponding
certificate should be present. If additional certificates are
present, they will also be included in the PKCS#12 file.
-inkey file
File to read a private key from. If not present, a private key must
be present in the input file.
-keyex | -keysig
Specify whether the private key is to be used for key exchange or
just signing. Normally, "export grade" software will only allow
512-bit RSA keys to be used for encryption purposes, but arbitrary
length keys for signing. The -keysig option marks the key for
signing only. Signing only keys can be used for S/MIME signing,
authenticode (ActiveX control signing) and SSL client authentication.
-macalg alg
Specify the MAC digest algorithm. The default is SHA1.
-maciter
Included for compatibility only: it used to be needed to use MAC
iterations counts but they are now used by default.
-name name
Specify the "friendly name" for the certificate and private key.
This name is typically displayed in list boxes by software importing
the file.
-nomac
Don't attempt to provide the MAC integrity.
-nomaciter, -noiter
Affect the iteration counts on the MAC and key algorithms.
To discourage attacks by using large dictionaries of common
passwords, the algorithm that derives keys from passwords can have an
iteration count applied to it: this causes a certain part of the
algorithm to be repeated and slows it down. The MAC is used to check
the file integrity but since it will normally have the same password
as the keys and certificates it could also be attacked. By default,
both MAC and encryption iteration counts are set to 2048; using these
options the MAC and encryption iteration counts can be set to 1.
Since this reduces the file security you should not use these options
unless you really have to. Most software supports both MAC and key
iteration counts.
-out file
The output file to write to, or standard output if not specified.
-passin arg
The key password source.
-passout arg
The output file password source.
PKEY
openssl pkey [cipher] [-in file] [-inform der | pem] [-noout] [-out file]
[-outform der | pem] [-passin arg] [-passout arg] [-pubin]
[-pubout] [-text] [-text_pub]
The pkey command processes public or private keys. They can be converted
between various forms and their components printed out.
The options are as follows:
cipher Encrypt the private key with the specified cipher. Any algorithm
name accepted by EVP_get_cipherbyname(3) is acceptable, such as
des3.
-in file
The input file to read from, or standard input if not specified.
If the key is encrypted a pass phrase will be prompted for.
-inform der | pem
The input format.
-noout Do not output the encoded version of the key.
-out file
The output file to write to, or standard output if not specified.
If any encryption options are set then a pass phrase will be
prompted for.
-outform der | pem
The output format.
-passin arg
The key password source.
-passout arg
The output file password source.
-pubin Read in a public key, not a private key.
-pubout
Output a public key, not a private key. Automatically set if the
input is a public key.
-text Print the public/private key in plain text.
-text_pub
Print out only public key components even if a private key is being
processed.
PKEYPARAM
openssl pkeyparam [-in file] [-noout] [-out file] [-text]
The pkeyparam command processes public or private keys. The key type is
determined by the PEM headers.
The options are as follows:
-in file
The input file to read from, or standard input if not specified.
-noout Do not output the encoded version of the parameters.
-out file
The output file to write to, or standard output if not specified.
-text Print the parameters in plain text.
PKEYUTL
openssl pkeyutl [-asn1parse] [-certin] [-decrypt] [-derive] [-encrypt]
[-hexdump] [-in file] [-inkey file] [-keyform der | pem]
[-out file] [-passin arg] [-peerform der | pem]
[-peerkey file] [-pkeyopt opt:value] [-pubin] [-rev]
[-sigfile file] [-sign] [-verify] [-verifyrecover]
The pkeyutl command can be used to perform public key operations using any
supported algorithm.
The options are as follows:
-asn1parse
ASN.1 parse the output data. This is useful when combined with the
-verifyrecover option when an ASN.1 structure is signed.
-certin
The input is a certificate containing a public key.
-decrypt
Decrypt the input data using a private key.
-derive
Derive a shared secret using the peer key.
-encrypt
Encrypt the input data using a public key.
-hexdump
Hex dump the output data.
-in file
The input file to read from, or standard input if not specified.
-inkey file
The input key file. By default it should be a private key.
-keyform der | pem
The key format.
-out file
The output file to write to, or standard output if not specified.
-passin arg
The key password source.
-peerform der | pem
The peer key format.
-peerkey file
The peer key file, used by key derivation (agreement) operations.
-pkeyopt opt:value
Set the public key algorithm option opt to value. Unless otherwise
mentioned, all algorithms support the format digest:alg, which
specifies the digest to use for sign, verify, and verifyrecover
operations. The value alg should represent a digest name as used
in the EVP_get_digestbyname(3) function.
The RSA algorithm supports the encrypt, decrypt, sign, verify, and
verifyrecover operations in general. Some padding modes only
support some of these operations however.
rsa_padding_mode:mode
This sets the RSA padding mode. Acceptable values for mode
are pkcs1 for PKCS#1 padding; none for no padding; oaep for
OAEP mode; x931 for X9.31 mode; and pss for PSS.
In PKCS#1 padding if the message digest is not set then the
supplied data is signed or verified directly instead of
using a DigestInfo structure. If a digest is set then a
DigestInfo structure is used and its length must correspond
to the digest type. For oeap mode only encryption and
decryption is supported. For x931 if the digest type is
set it is used to format the block data; otherwise the
first byte is used to specify the X9.31 digest ID. Sign,
verify, and verifyrecover can be performed in this mode.
For pss mode only sign and verify are supported and the
digest type must be specified.
rsa_pss_saltlen:len
For pss mode only this option specifies the salt length.
Two special values are supported: -1 sets the salt length
to the digest length. When signing -2 sets the salt length
to the maximum permissible value. When verifying -2 causes
the salt length to be automatically determined based on the
PSS block structure.
The DSA algorithm supports the sign and verify operations.
Currently there are no additional options other than digest. Only
the SHA1 digest can be used and this digest is assumed by default.
The DH algorithm supports the derive operation and no additional
options.
The EC algorithm supports the sign, verify, and derive operations.
The sign and verify operations use ECDSA and derive uses ECDH.
Currently there are no additional options other than digest. Only
the SHA1 digest can be used and this digest is assumed by default.
-pubin The input file is a public key.
-rev Reverse the order of the input buffer.
-sigfile file
Signature file (verify operation only).
-sign Sign the input data and output the signed result. This requires a
private key.
-verify
Verify the input data against the signature file and indicate if
the verification succeeded or failed.
-verifyrecover
Verify the input data and output the recovered data.
PRIME
openssl prime [-bits n] [-checks n] [-generate] [-hex] [-safe] p
The prime command is used to generate prime numbers, or to check numbers
for primality. Results are probabilistic: they have an exceedingly high
likelihood of being correct, but are not guaranteed.
The options are as follows:
-bits n
Specify the number of bits in the generated prime number. Must be
used in conjunction with -generate.
-checks n
Perform a Miller-Rabin probabilistic primality test with n
iterations. The default is 20.
-generate
Generate a pseudo-random prime number. Must be used in conjunction
with -bits.
-hex Output in hex format.
-safe Generate only "safe" prime numbers (i.e. a prime p so that (p-1)/2
is also prime).
p Test if number p is prime.
RAND
openssl rand [-base64] [-hex] [-out file] num
The rand command outputs num pseudo-random bytes.
The options are as follows:
-base64
Perform base64 encoding on the output.
-hex Specify hexadecimal output.
-out file
The output file to write to, or standard output if not specified.
REQ
openssl req [-asn1-kludge] [-batch] [-config file] [-days n]
[-extensions section] [-in file] [-inform der | pem]
[-key keyfile] [-keyform der | pem] [-keyout file]
[-md4 | -md5 | -sha1] [-modulus] [-nameopt option] [-new]
[-newhdr] [-newkey arg] [-no-asn1-kludge] [-nodes] [-noout]
[-out file] [-outform der | pem] [-passin arg] [-passout arg]
[-pubkey] [-reqexts section] [-reqopt option] [-set_serial n]
[-subj arg] [-subject] [-text] [-utf8] [-verbose] [-verify]
[-x509]
The req command primarily creates and processes certificate requests in
PKCS#10 format. It can additionally create self-signed certificates, for
use as root CAs, for example.
The options are as follows:
-asn1-kludge
Produce requests in an invalid format for certain picky CAs. Very
few CAs still require the use of this option.
-batch Non-interactive mode.
-config file
Specify an alternative configuration file.
-days n
Specify the number of days to certify the certificate for. The
default is 30 days. Used with the -x509 option.
-extensions section, -reqexts section
Specify alternative sections to include certificate extensions
(with -x509) or certificate request extensions, allowing several
different sections to be used in the same configuration file.
-in file
The input file to read a request from, or standard input if not
specified. A request is only read if the creation options -new and
-newkey are not specified.
-inform der | pem
The input format.
-key keyfile
The file to read the private key from. It also accepts PKCS#8
format private keys for PEM format files.
-keyform der | pem
The format of the private key file specified in the -key argument.
The default is pem.
-keyout file
The file to write the newly created private key to. If this option
is not specified, the filename present in the configuration file is
used.
-md5 | -sha1 | -sha256
The message digest to sign the request with. This overrides the
digest algorithm specified in the configuration file.
Some public key algorithms may override this choice. For instance,
DSA signatures always use SHA1.
-modulus
Print the value of the modulus of the public key contained in the
request.
-nameopt option, -reqopt option
Determine how the subject or issuer names are displayed. option
can be a single option or multiple options separated by commas.
Alternatively, these options may be used more than once to set
multiple options. See the X509 section below for details.
-new Generate a new certificate request. The user is prompted for the
relevant field values. The actual fields prompted for and their
maximum and minimum sizes are specified in the configuration file
and any requested extensions.
If the -key option is not used, it will generate a new RSA private
key using information specified in the configuration file.
-newhdr
Add the word NEW to the PEM file header and footer lines on the
outputed request. Some software and CAs need this.
-newkey arg
Create a new certificate request and a new private key. The
argument takes one of several forms.
rsa:nbits generates an RSA key nbits in size. If nbits is omitted
the default key size is used.
dsa:file generates a DSA key using the parameters in file.
param:file generates a key using the parameters or certificate in
file.
All other algorithms support the form algorithm:file, where file
may be an algorithm parameter file, created by the genpkey
-genparam command or an X.509 certificate for a key with
appropriate algorithm. file can be omitted, in which case any
parameters can be specified via the -pkeyopt option.
-no-asn1-kludge
Reverse the effect of -asn1-kludge.
-nodes Do not encrypt the private key.
-noout Do not output the encoded version of the request.
-out file
The output file to write to, or standard output if not spceified.
-outform der | pem
The output format.
-passin arg
The key password source.
-passout arg
The output file password source.
-pubkey
Output the public key.
-reqopt option
Customise the output format used with -text. The option argument
can be a single option or multiple options separated by commas.
See also the discussion of -certopt in the x509 command.
-set_serial n
Serial number to use when outputting a self-signed certificate.
This may be specified as a decimal value or a hex value if preceded
by ‘0x’. It is possible to use negative serial numbers but this is
not recommended.
-subj arg
Replaces the subject field of an input request with the specified
data and output the modified request. arg must be formatted as
/type0=value0/type1=value1/type2=...; characters may be escaped by
‘\’ (backslash); no spaces are skipped.
-subject
Print the request subject (or certificate subject if -x509 is
specified).
-text Print the certificate request in plain text.
-utf8 Interpret field values as UTF8 strings, not ASCII.
-verbose
Print extra details about the operations being performed.
-verify
Verify the signature on the request.
-x509 Output a self-signed certificate instead of a certificate request.
This is typically used to generate a test certificate or a self-
signed root CA. The extensions added to the certificate (if any)
are specified in the configuration file. Unless specified using
the -set_serial option, 0 is used for the serial number.
The configuration options are specified in the "req" section of the
configuration file. The options available are as follows:
attributes
The section containing any request attributes: its format is the same
as distinguished_name. Typically these may contain the
challengePassword or unstructuredName types. They are currently
ignored by the openssl request signing utilities, but some CAs might
want them.
default_bits
The default key size, in bits. The default is 2048. It is used if
the -new option is used and can be overridden by using the -newkey
option.
default_keyfile
The default file to write a private key to, or standard output if not
specified. It can be overridden by the -keyout option.
default_md
The digest algorithm to use. Possible values include md5, sha1 and
sha256 (the default). It can be overridden on the command line.
distinguished_name
The section containing the distinguished name fields to prompt for
when generating a certificate or certificate request. The format is
described below.
encrypt_key
If set to "no" and a private key is generated, it is not encrypted.
It is equivalent to the -nodes option. For compatibility,
encrypt_rsa_key is an equivalent option.
input_password | output_password
The passwords for the input private key file (if present) and the
output private key file (if one will be created). The command line
options -passin and -passout override the configuration file values.
oid_file
A file containing additional OBJECT IDENTIFIERS. Each line of the
file should consist of the numerical form of the object identifier,
followed by whitespace, then the short name followed by whitespace
and finally the long name.
oid_section
Specify a section in the configuration file containing extra object
identifiers. Each line should consist of the short name of the
object identifier followed by ‘=’ and the numerical form. The short
and long names are the same when this option is used.
prompt
If set to "no", it disables prompting of certificate fields and just
takes values from the config file directly. It also changes the
expected format of the distinguished_name and attributes sections.
req_extensions
The configuration file section containing a list of extensions to add
to the certificate request. It can be overridden by the -reqexts
option.
string_mask
Limit the string types for encoding certain fields. The following
values may be used, limiting strings to the indicated types:
utf8only UTF8String. This is the default, as recommended by PKIX
in RFC 2459.
default PrintableString, IA5String, T61String, BMPString,
UTF8String.
pkix PrintableString, IA5String, BMPString, UTF8String.
Inspired by the PKIX recommendation in RFC 2459 for
certificates generated before 2004, but differs by also
permitting IA5String.
nombstr PrintableString, IA5String, T61String, UniversalString.
A workaround for some ancient software that had problems
with the variable-sized BMPString and UTF8String types.
MASK:number An explicit bitmask of permitted types, where number is
a C-style hex, decimal, or octal number that's a bit-
wise OR of B_ASN1_* values from <openssl/asn1.h>.
utf8 If set to "yes", field values are interpreted as UTF8 strings.
x509_extensions
The configuration file section containing a list of extensions to add
to a certificate generated when the -x509 switch is used. It can be
overridden by the -extensions command line switch.
There are two separate formats for the distinguished name and attribute
sections. If the -prompt option is set to "no", then these sections just
consist of field names and values. If the -prompt option is absent or not
set to "no", then the file contains field prompting information of the
form:
fieldName="prompt"
fieldName_default="default field value"
fieldName_min= 2
fieldName_max= 4
"fieldName" is the field name being used, for example commonName (or CN).
The "prompt" string is used to ask the user to enter the relevant details.
If the user enters nothing, the default value is used; if no default value
is present, the field is omitted. A field can still be omitted if a
default value is present, if the user just enters the ‘.’ character.
The number of characters entered must be between the fieldName_min and
fieldName_max limits: there may be additional restrictions based on the
field being used (for example countryName can only ever be two characters
long and must fit in a PrintableString).
Some fields (such as organizationName) can be used more than once in a DN.
This presents a problem because configuration files will not recognize the
same name occurring twice. To avoid this problem, if the fieldName
contains some characters followed by a full stop, they will be ignored.
So, for example, a second organizationName can be input by calling it
"1.organizationName".
The actual permitted field names are any object identifier short or long
names. These are compiled into openssl and include the usual values such
as commonName, countryName, localityName, organizationName,
organizationalUnitName, stateOrProvinceName. Additionally, emailAddress is
included as well as name, surname, givenName, initials and dnQualifier.
Additional object identifiers can be defined with the oid_file or
oid_section options in the configuration file. Any additional fields will
be treated as though they were a DirectoryString.
RSA
openssl rsa [-aes128 | -aes192 | -aes256 | -des | -des3] [-check]
[-in file] [-inform der | net | pem] [-modulus] [-noout]
[-out file] [-outform der | net | pem] [-passin arg]
[-passout arg] [-pubin] [-pubout] [-sgckey] [-text]
The rsa command processes RSA keys. They can be converted between various
forms and their components printed out. rsa uses the traditional SSLeay
compatible format for private key encryption: newer applications should use
the more secure PKCS#8 format using the pkcs8 utility.
The options are as follows:
-aes128 | -aes192 | -aes256 | -des | -des3
Encrypt the private key with the AES, DES, or the triple DES
ciphers, respectively, before outputting it. A pass phrase is
prompted for. If none of these options are specified, the key is
written in plain text. This means that using the rsa utility to
read in an encrypted key with no encryption option can be used to
remove the pass phrase from a key, or by setting the encryption
options it can be used to add or change the pass phrase. These
options can only be used with PEM format output files.
-check Check the consistency of an RSA private key.
-in file
The input file to read from, or standard input if not specified.
If the key is encrypted, a pass phrase will be prompted for.
-inform der | net | pem
The input format.
-noout Do not output the encoded version of the key.
-modulus
Print the value of the modulus of the key.
-out file
The output file to write to, or standard output if not specified.
-outform der | net | pem
The output format.
-passin arg
The key password source.
-passout arg
The output file password source.
-pubin Read in a public key, not a private key.
-pubout
Output a public key, not a private key. Automatically set if the
input is a public key.
-sgckey
Use the modified NET algorithm used with some versions of Microsoft
IIS and SGC keys.
-text Print the public/private key components in plain text.
RSAUTL
openssl rsautl [-asn1parse] [-certin] [-decrypt] [-encrypt] [-hexdump]
[-in file] [-inkey file] [-keyform der | pem]
[-oaep | -pkcs | -raw] [-out file] [-pubin] [-sign]
[-verify]
The rsautl command can be used to sign, verify, encrypt and decrypt data
using the RSA algorithm.
The options are as follows:
-asn1parse
Asn1parse the output data; this is useful when combined with the
-verify option.
-certin
The input is a certificate containing an RSA public key.
-decrypt
Decrypt the input data using an RSA private key.
-encrypt
Encrypt the input data using an RSA public key.
-hexdump
Hex dump the output data.
-in file
The input to read from, or standard input if not specified.
-inkey file
The input key file; by default an RSA private key.
-keyform der | pem
The private key format. The default is pem.
-oaep | -pkcs | -raw
The padding to use: PKCS#1 OAEP, PKCS#1 v1.5 (the default), or no
padding, respectively. For signatures, only -pkcs and -raw can be
used.
-out file
The output file to write to, or standard output if not specified.
-pubin The input file is an RSA public key.
-sign Sign the input data and output the signed result. This requires an
RSA private key.
-verify
Verify the input data and output the recovered data.
S_CLIENT
openssl s_client [-4 | -6] [-bugs] [-CAfile file] [-CApath directory]
[-cert file] [-check_ss_sig] [-cipher cipherlist]
[-connect host[:port]] [-crl_check] [-crl_check_all]
[-crlf] [-debug] [-extended_crl] [-groups] [-ign_eof]
[-ignore_critical] [-issuer_checks] [-key keyfile] [-msg]
[-nbio] [-nbio_test] [-no_ticket] [-no_tls1] [-no_tls1_1]
[-no_tls1_2] [-pause] [-policy_check] [-prexit]
[-proxy host:port] [-psk key] [-psk_identity identity]
[-quiet] [-reconnect] [-servername name] [-showcerts]
[-starttls protocol] [-state] [-tls1] [-tls1_1] [-tls1_2]
[-tlsextdebug] [-verify depth] [-x509_strict]
[-xmpphost host]
The s_client command implements a generic SSL/TLS client which connects to
a remote host using SSL/TLS.
If a connection is established with an SSL server, any data received from
the server is displayed and any key presses will be sent to the server.
When used interactively (which means neither -quiet nor -ign_eof have been
given), the session will be renegotiated if the line begins with an R; if
the line begins with a Q or if end of file is reached, the connection will
be closed down.
The options are as follows:
-4 Attempt connections using IPv4 only.
-6 Attempt connections using IPv6 only.
-bugs Enable various workarounds for buggy implementations.
-CAfile file
A file containing trusted certificates to use during server
authentication and to use when attempting to build the client
certificate chain.
-CApath directory
The directory to use for server certificate verification. This
directory must be in "hash format"; see -verify for more
information. These are also used when building the client
certificate chain.
-cert file
The certificate to use, if one is requested by the server. The
default is not to use a certificate.
-check_ss_sig, -crl_check, -crl_check_all, -extended_crl, -ignore_critical,
-issuer_checks, -policy_check, -x509_strict
Set various certificate chain validation options. See the verify
command for details.
-cipher cipherlist
Modify the cipher list sent by the client. Although the server
determines which cipher suite is used, it should take the first
supported cipher in the list sent by the client. See the ciphers
command for more information.
-connect host[:port]
The host and port to connect to. If not specified, an attempt is
made to connect to the local host on port 4433. Alternatively, the
host and port pair may be separated using a forward-slash
character, which is useful for numeric IPv6 addresses.
-crlf Translate a line feed from the terminal into CR+LF, as required by
some servers.
-debug Print extensive debugging information, including a hex dump of all
traffic.
-groups ecgroups
Specify a colon-separated list of permitted EC curve groups.
-ign_eof
Inhibit shutting down the connection when end of file is reached in
the input.
-key keyfile
The private key to use. If not specified, the certificate file
will be used.
-msg Show all protocol messages with hex dump.
-nbio Turn on non-blocking I/O.
-nbio_test
Test non-blocking I/O.
-no_tls1 | -no_tls1_1 | -no_tls1_2
Disable the use of TLS1.0, 1.1, and 1.2, respectively.
-no_ticket
Disable RFC 4507 session ticket support.
-pause Pause 1 second between each read and write call.
-prexit
Print session information when the program exits. This will always
attempt to print out information even if the connection fails.
Normally, information will only be printed out once if the
connection succeeds. This option is useful because the cipher in
use may be renegotiated or the connection may fail because a client
certificate is required or is requested only after an attempt is
made to access a certain URL. Note that the output produced by
this option is not always accurate because a connection might never
have been established.
-proxy host:port
Use the HTTP proxy at host and port. The connection to the proxy
is done in cleartext and the -connect argument is given to the
proxy. If not specified, localhost is used as final destination.
After that, switch the connection through the proxy to the
destination to TLS.
-psk key
Use the PSK key key when using a PSK cipher suite. The key is
given as a hexadecimal number without the leading 0x, for example
-psk 1a2b3c4d.
-psk_identity identity
Use the PSK identity when using a PSK cipher suite.
-quiet Inhibit printing of session and certificate information. This
implicitly turns on -ign_eof as well.
-reconnect
Reconnect to the same server 5 times using the same session ID;
this can be used as a test that session caching is working.
-servername name
Include the TLS Server Name Indication (SNI) extension in the
ClientHello message, using the specified server name.
-showcerts
Display the whole server certificate chain: normally only the
server certificate itself is displayed.
-starttls protocol
Send the protocol-specific messages to switch to TLS for
communication. protocol is a keyword for the intended protocol.
Currently, the supported keywords are "ftp", "imap", "smtp",
"pop3", and "xmpp".
-state Print the SSL session states.
-tls1 | -tls1_1 | -tls1_2
Permit only TLS1.0, 1.1, or 1.2, respectively.
-tlsextdebug
Print a hex dump of any TLS extensions received from the server.
-verify depth
Turn on server certificate verification, with a maximum length of
depth. Currently the verify operation continues after errors so
all the problems with a certificate chain can be seen. As a side
effect the connection will never fail due to a server certificate
verify failure.
-xmpphost hostname
When used with -starttls xmpp, specify the host for the "to"
attribute of the stream element. If this option is not specified
then the host specified with -connect will be used.
S_SERVER
openssl s_server [-accept port] [-bugs] [-CAfile file] [-CApath directory]
[-cert file] [-cipher cipherlist] [-context id]
[-crl_check] [-crl_check_all] [-crlf] [-dcert file]
[-debug] [-dhparam file] [-dkey file] [-hack] [-HTTP]
[-id_prefix arg] [-key keyfile] [-msg] [-nbio]
[-nbio_test] [-no_dhe] [-no_tls1] [-no_tls1_1]
[-no_tls1_2] [-no_tmp_rsa] [-nocert] [-psk key]
[-psk_hint hint] [-quiet] [-serverpref] [-state] [-tls1]
[-tls1_1] [-tls1_2] [-Verify depth] [-verify depth] [-WWW]
[-www]
The s_server command implements a generic SSL/TLS server which listens for
connections on a given port using SSL/TLS.
If a connection request is established with a client and neither the -www
nor the -WWW option has been used, then any data received from the client
is displayed and any key presses are sent to the client. Certain single
letter commands perform special operations:
P Send plain text, which should cause the client to disconnect.
Q End the current SSL connection and exit.
q End the current SSL connection, but still accept new connections.
R Renegotiate the SSL session and request a client certificate.
r Renegotiate the SSL session.
S Print out some session cache status information.
The options are as follows:
-accept port
Listen on TCP port for connections. The default is port 4433.
-bugs Enable various workarounds for buggy implementations.
-CAfile file
A file containing trusted certificates to use during client
authentication and to use when attempting to build the server
certificate chain. The list is also used in the list of acceptable
client CAs passed to the client when a certificate is requested.
-CApath directory
The directory to use for client certificate verification. This
directory must be in "hash format"; see -verify for more
information. These are also used when building the server
certificate chain.
-cert file
The certificate to use: most server's cipher suites require the use
of a certificate and some require a certificate with a certain
public key type. For example, the DSS cipher suites require a
certificate containing a DSS (DSA) key. If not specified, the file
server.pem will be used.
-cipher cipherlist
Modify the cipher list used by the server. This allows the cipher
list used by the server to be modified. When the client sends a
list of supported ciphers, the first client cipher also included in
the server list is used. Because the client specifies the
preference order, the order of the server cipherlist is irrelevant.
See the ciphers command for more information.
-context id
Set the SSL context ID. It can be given any string value.
-crl_check, -crl_check_all
Check the peer certificate has not been revoked by its CA. The
CRLs are appended to the certificate file. -crl_check_all checks
all CRLs of all CAs in the chain.
-crlf Translate a line feed from the terminal into CR+LF.
-dcert file, -dkey file
Specify an additional certificate and private key; these behave in
the same manner as the -cert and -key options except there is no
default if they are not specified (no additional certificate or key
is used). By using RSA and DSS certificates and keys, a server can
support clients which only support RSA or DSS cipher suites by
using an appropriate certificate.
-debug Print extensive debugging information, including a hex dump of all
traffic.
-dhparam file
The DH parameter file to use. The ephemeral DH cipher suites
generate keys using a set of DH parameters. If not specified, an
attempt is made to load the parameters from the server certificate
file. If this fails, a static set of parameters hard coded into
the s_server program will be used.
-hack Enables a further workaround for some early Netscape SSL code.
-HTTP Emulate a simple web server. Pages are resolved relative to the
current directory. For example if the URL https://myhost/page.html
is requested, the file ./page.html will be loaded. The files
loaded are assumed to contain a complete and correct HTTP response
(lines that are part of the HTTP response line and headers must end
with CRLF).
-id_prefix arg
Generate SSL/TLS session IDs prefixed by arg. This is mostly
useful for testing any SSL/TLS code that wish to deal with multiple
servers, when each of which might be generating a unique range of
session IDs.
-key keyfile
The private key to use. If not specified, the certificate file
will be used.
-msg Show all protocol messages with hex dump.
-nbio Turn on non-blocking I/O.
-nbio_test
Test non-blocking I/O.
-no_dhe
Disable ephemeral DH cipher suites.
-no_tls1 | -no_tls1_1 | -no_tls1_2
Disable the use of TLS1.0, 1.1, and 1.2, respectively.
-no_tmp_rsa
Disable temporary RSA key generation.
-nocert
Do not use a certificate. This restricts the cipher suites
available to the anonymous ones (currently just anonymous DH).
-psk key
Use the PSK key key when using a PSK cipher suite. The key is
given as a hexadecimal number without the leading 0x, for example
-psk 1a2b3c4d.
-psk_hint hint
Use the PSK identity hint hint when using a PSK cipher suite.
-quiet Inhibit printing of session and certificate information.
-serverpref
Use server's cipher preferences.
-state Print the SSL session states.
-tls1 | -tls1_1 | -tls1_2
Permit only TLS1.0, 1.1, or 1.2, respectively.
-WWW Emulate a simple web server. Pages are resolved relative to the
current directory. For example if the URL https://myhost/page.html
is requested, the file ./page.html will be loaded.
-www Send a status message to the client when it connects, including
information about the ciphers used and various session parameters.
The output is in HTML format so this option will normally be used
with a web browser.
-Verify depth, -verify depth
Request a certificate chain from the client, with a maximum length
of depth. With -Verify, the client must supply a certificate or an
error occurs; with -verify, a certificate is requested but the
client does not have to send one.
S_TIME
openssl s_time [-bugs] [-CAfile file] [-CApath directory] [-cert file]
[-cipher cipherlist] [-connect host[:port]] [-key keyfile]
[-nbio] [-new] [-no_shutdown] [-reuse] [-time seconds]
[-verify depth] [-www page]
The s_time command implements a generic SSL/TLS client which connects to a
remote host using SSL/TLS. It can request a page from the server and
includes the time to transfer the payload data in its timing measurements.
It measures the number of connections within a given timeframe, the amount
of data transferred (if any), and calculates the average time spent for one
connection.
The options are as follows:
-bugs Enable various workarounds for buggy implementations.
-CAfile file
A file containing trusted certificates to use during server
authentication and to use when attempting to build the client
certificate chain.
-CApath directory
The directory to use for server certificate verification. This
directory must be in "hash format"; see verify for more
information. These are also used when building the client
certificate chain.
-cert file
The certificate to use, if one is requested by the server. The
default is not to use a certificate.
-cipher cipherlist
Modify the cipher list sent by the client. Although the server
determines which cipher suite is used, it should take the first
supported cipher in the list sent by the client. See the ciphers
command for more information.
-connect host[:port]
The host and port to connect to.
-key keyfile
The private key to use. If not specified, the certificate file
will be used.
-nbio Turn on non-blocking I/O.
-new Perform the timing test using a new session ID for each connection.
If neither -new nor -reuse are specified, they are both on by
default and executed in sequence.
-no_shutdown
Shut down the connection without sending a "close notify" shutdown
alert to the server.
-reuse Perform the timing test using the same session ID for each
connection. If neither -new nor -reuse are specified, they are
both on by default and executed in sequence.
-time seconds
Limit s_time benchmarks to the number of seconds. The default is
30 seconds.
-verify depth
Turn on server certificate verification, with a maximum length of
depth. Currently the verify operation continues after errors, so
all the problems with a certificate chain can be seen. As a side
effect, the connection will never fail due to a server certificate
verify failure.
-www page
The page to GET from the server. A value of ‘/’ gets the
index.htm[l] page. If this parameter is not specified, s_time will
only perform the handshake to establish SSL connections but not
transfer any payload data.
SESS_ID
openssl sess_id [-cert] [-context ID] [-in file] [-inform der | pem]
[-noout] [-out file] [-outform der | pem] [-text]
The sess_id program processes the encoded version of the SSL session
structure and optionally prints out SSL session details (for example the
SSL session master key) in human-readable format.
The options are as follows:
-cert If a certificate is present in the session, it will be output using
this option; if the -text option is also present, then it will be
printed out in text form.
-context ID
Set the session ID. The ID can be any string of characters.
-in file
The input file to read from, or standard input if not specified.
-inform der | pem
The input format. der uses an ASN.1 DER-encoded format containing
session details. The precise format can vary from one version to
the next. pem is the default format: it consists of the DER format
base64-encoded with additional header and footer lines.
-noout Do not output the encoded version of the session.
-out file
The output file to write to, or standard output if not specified.
-outform der | pem
The output format.
-text Print the various public or private key components in plain text,
in addition to the encoded version.
The output of sess_id is composed as follows:
Protocol The protocol in use.
Cipher The actual raw SSL or TLS cipher code.
Session-ID The SSL session ID, in hex format.
Session-ID-ctx The session ID context, in hex format.
Master-Key The SSL session master key.
Key-Arg The key argument; this is only used in SSL v2.
Start Time The session start time. UNIX format.
Timeout The timeout, in seconds.
Verify return code The return code when a certificate is verified.
Since the SSL session output contains the master key, it is possible to
read the contents of an encrypted session using this information.
Therefore appropriate security precautions should be taken if the
information is being output by a "real" application. This is, however,
strongly discouraged and should only be used for debugging purposes.
SMIME
openssl smime [-aes128 | -aes192 | -aes256 | -des |
-des3 | -rc2-40 | -rc2-64 | -rc2-128] [-binary]
[-CAfile file] [-CApath directory] [-certfile file]
[-check_ss_sig] [-content file] [-crl_check] [-crl_check_all]
[-decrypt] [-encrypt] [-extended_crl] [-from addr]
[-ignore_critical] [-in file] [-indef]
[-inform der | pem | smime] [-inkey file] [-issuer_checks]
[-keyform pem] [-md digest] [-noattr] [-nocerts] [-nochain]
[-nodetach] [-noindef] [-nointern] [-nosigs] [-noverify]
[-out file] [-outform der | pem | smime] [-passin arg]
[-pk7out] [-policy_check] [-recip file] [-resign] [-sign]
[-signer file] [-stream] [-subject s] [-text] [-to addr]
[-verify] [-x509_strict] [cert.pem ...]
The smime command handles S/MIME mail. It can encrypt, decrypt, sign, and
verify S/MIME messages.
The MIME message must be sent without any blank lines between the headers
and the output. Some mail programs will automatically add a blank line.
Piping the mail directly to an MTA is one way to achieve the correct
format.
The supplied message to be signed or encrypted must include the necessary
MIME headers or many S/MIME clients won't display it properly (if at all).
Use the -text option to automatically add plain text headers.
A "signed and encrypted" message is one where a signed message is then
encrypted. This can be produced by encrypting an already signed message.
There are a number of operations that can be performed, as follows:
-decrypt
Decrypt mail using the supplied certificate and private key. The
input file is an encrypted mail message in MIME format. The
decrypted mail is written to the output file.
-encrypt
Encrypt mail for the given recipient certificates. The input is the
message to be encrypted. The output file is the encrypted mail, in
MIME format.
-pk7out
Take an input message and write out a PEM-encoded PKCS#7 structure.
-resign
Resign a message: take an existing message and one or more new
signers.
-sign
Sign mail using the supplied certificate and private key. The input
file is the message to be signed. The signed message, in MIME
format, is written to the output file.
-verify
Verify signed mail. The input is a signed mail message and the
output is the signed data. Both clear text and opaque signing is
supported.
The remaining options are as follows:
-aes128 | -aes192 | -aes256 | -des | -des3 | -rc2-40 | -rc2-64 | -rc2-128
The encryption algorithm to use. 128-, 192-, or 256-bit AES, DES (56
bits), triple DES (168 bits), or 40-, 64-, or 128-bit RC2,
respectively; if not specified, 40-bit RC2 is used. Only used with
-encrypt.
-binary
Normally, the input message is converted to "canonical" format which
uses CR/LF as end of line, as required by the S/MIME specification.
When this option is present no translation occurs. This is useful
when handling binary data which may not be in MIME format.
-CAfile file
A file containing trusted CA certificates; only used with -verify.
-CApath directory
A directory containing trusted CA certificates; only used with
-verify. This directory must be a standard certificate directory:
that is, a hash of each subject name (using x509 -hash) should be
linked to each certificate.
cert.pem ...
One or more certificates of message recipients: used when encrypting
a message.
-certfile file
Allows additional certificates to be specified. When signing, these
will be included with the message. When verifying, these will be
searched for the signers' certificates. The certificates should be
in PEM format.
-check_ss_sig, -crl_check, -crl_check_all, -extended_crl, -ignore_critical,
-issuer_checks, -policy_check, -x509_strict
Set various certificate chain validation options. See the verify
command for details.
-content file
A file containing the detached content. This is only useful with the
-verify option, and only usable if the PKCS#7 structure is using the
detached signature form where the content is not included. This
option will override any content if the input format is S/MIME and it
uses the multipart/signed MIME content type.
-from addr, -subject s, -to addr
The relevant mail headers. These are included outside the signed
portion of a message so they may be included manually. When signing,
many S/MIME mail clients check that the signer's certificate email
address matches the From: address.
-in file
The input file to read from.
-indef
Enable streaming I/O for encoding operations. This permits single
pass processing of data without the need to hold the entire contents
in memory, potentially supporting very large files. Streaming is
automatically set for S/MIME signing with detached data if the output
format is SMIME; it is currently off by default for all other
operations.
-inform der | pem | smime
The input format.
-inkey file
The private key to use when signing or decrypting, which must match
the corresponding certificate. If this option is not specified, the
private key must be included in the certificate file specified with
the -recip or -signer file. When signing, this option can be used
multiple times to specify successive keys.
-keyform pem
Input private key format.
-md digest
The digest algorithm to use when signing or resigning. If not
present then the default digest algorithm for the signing key is used
(usually SHA1).
-noattr
Do not include attributes.
-nocerts
Do not include the signer's certificate. This will reduce the size
of the signed message but the verifier must have a copy of the
signer's certificate available locally (passed using the -certfile
option, for example).
-nochain
Do not do chain verification of signers' certificates: that is, don't
use the certificates in the signed message as untrusted CAs.
-nodetach
When signing a message use opaque signing: this form is more
resistant to translation by mail relays but it cannot be read by mail
agents that do not support S/MIME. Without this option cleartext
signing with the MIME type multipart/signed is used.
-noindef
Disable streaming I/O where it would produce an encoding of
indefinite length (currently has no effect).
-nointern
Only use certificates specified in the -certfile. The supplied
certificates can still be used as untrusted CAs.
-nosigs
Do not try to verify the signatures on the message.
-noverify
Do not verify the signer's certificate of a signed message.
-out file
The output file to write to.
-outform der | pem | smime
The output format. The default is smime, which writes an S/MIME
format message. pem and der change this to write PEM and DER format
PKCS#7 structures instead. This currently only affects the output
format of the PKCS#7 structure; if no PKCS#7 structure is being
output (for example with -verify or -decrypt) this option has no
effect.
-passin arg
The key password source.
-recip file
The recipients certificate when decrypting a message. This
certificate must match one of the recipients of the message or an
error occurs.
-signer file
A signing certificate when signing or resigning a message; this
option can be used multiple times if more than one signer is
required. If a message is being verified, the signer's certificates
will be written to this file if the verification was successful.
-stream
The same as -indef.
-text
Add plain text (text/plain) MIME headers to the supplied message if
encrypting or signing. If decrypting or verifying, it strips off
text headers: if the decrypted or verified message is not of MIME
type text/plain then an error occurs.
The exit codes for smime are as follows:
0 The operation was completely successful.
1 An error occurred parsing the command options.
2 One of the input files could not be read.
3 An error occurred creating the file or when reading the message.
4 An error occurred decrypting or verifying the message.
5 An error occurred writing certificates.
SPEED
openssl speed [algorithm] [-decrypt] [-elapsed] [-evp algorithm] [-mr]
[-multi number]
The speed command is used to test the performance of cryptographic
algorithms.
algorithm
Perform the test using algorithm. The default is to test all
algorithms.
-decrypt
Time decryption instead of encryption; must be used with -evp.
-elapsed
Measure time in real time instead of CPU user time.
-evp algorithm
Perform the test using one of the algorithms accepted by
EVP_get_cipherbyname(3).
-mr Produce machine readable output.
-multi number
Run number benchmarks in parallel.
SPKAC
openssl spkac [-challenge string] [-in file] [-key keyfile] [-noout]
[-out file] [-passin arg] [-pubkey] [-spkac spkacname]
[-spksect section] [-verify]
The spkac command processes signed public key and challenge (SPKAC) files.
It can print out their contents, verify the signature, and produce its own
SPKACs from a supplied private key.
The options are as follows:
-challenge string
The challenge string, if an SPKAC is being created.
-in file
The input file to read from, or standard input if not specified.
Ignored if the -key option is used.
-key keyfile
Create an SPKAC file using the private key in keyfile. The -in,
-noout, -spksect, and -verify options are ignored, if present.
-noout Do not output the text version of the SPKAC.
-out file
The output file to write to, or standard output if not specified.
-passin arg
The key password source.
-pubkey
Output the public key of an SPKAC.
-spkac spkacname
An alternative name for the variable containing the SPKAC. The
default is "SPKAC". This option affects both generated and input
SPKAC files.
-spksect section
An alternative name for the section containing the SPKAC.
-verify
Verify the digital signature on the supplied SPKAC.
TS
openssl ts -query [-md4 | -md5 | -ripemd160 | -sha1] [-cert]
[-config configfile] [-data file_to_hash] [-digest digest_bytes]
[-in request.tsq] [-no_nonce] [-out request.tsq]
[-policy object_id] [-text]
openssl ts -reply [-chain certs_file.pem] [-config configfile]
[-in response.tsr] [-inkey private.pem] [-out response.tsr]
[-passin arg] [-policy object_id] [-queryfile request.tsq]
[-section tsa_section] [-signer tsa_cert.pem] [-text]
[-token_in] [-token_out]
openssl ts -verify [-CAfile trusted_certs.pem] [-CApath trusted_cert_path]
[-data file_to_hash] [-digest digest_bytes] [-in response.tsr]
[-queryfile request.tsq] [-token_in] [-untrusted cert_file.pem]
The ts command is a basic Time Stamping Authority (TSA) client and server
application as specified in RFC 3161 (Time-Stamp Protocol, TSP). A TSA can
be part of a PKI deployment and its role is to provide long term proof of
the existence of specific data. Here is a brief description of the
protocol:
1. The TSA client computes a one-way hash value for a data file and sends
the hash to the TSA.
2. The TSA attaches the current date and time to the received hash value,
signs them and sends the time stamp token back to the client. By
creating this token the TSA certifies the existence of the original
data file at the time of response generation.
3. The TSA client receives the time stamp token and verifies the
signature on it. It also checks if the token contains the same hash
value that it had sent to the TSA.
There is one DER-encoded protocol data unit defined for transporting a time
stamp request to the TSA and one for sending the time stamp response back
to the client. The ts command has three main functions: creating a time
stamp request based on a data file; creating a time stamp response based on
a request; and verifying if a response corresponds to a particular request
or a data file.
There is no support for sending the requests/responses automatically over
HTTP or TCP yet as suggested in RFC 3161. Users must send the requests
either by FTP or email.
The -query switch can be used for creating and printing a time stamp
request with the following options:
-cert Expect the TSA to include its signing certificate in the response.
-config configfile
Specify an alternative configuration file. Only the OID section is
used.
-data file_to_hash
The data file for which the time stamp request needs to be created.
The default is standard input.
-digest digest_bytes
Specify the message imprint explicitly without the data file. The
imprint must be specified in a hexadecimal format, two characters
per byte, the bytes optionally separated by colons. The number of
bytes must match the message digest algorithm in use.
-in request.tsq
A previously created time stamp request in DER format that will be
printed into the output file. Useful for examining the content of
a request in human-readable format.
-md4 | -md5 | -ripemd160 | -sha | -sha1
The message digest to apply to the data file. It supports all the
message digest algorithms that are supported by the dgst command.
The default is SHA-1.
-no_nonce
Specify no nonce in the request. The default, to include a 64-bit
long pseudo-random nonce, is recommended to protect against replay
attacks.
-out request.tsq
The output file to write to, or standard output if not specified.
-policy object_id
The policy that the client expects the TSA to use for creating the
time stamp token. Either dotted OID notation or OID names defined
in the config file can be used. If no policy is requested the TSA
uses its own default policy.
-text Output in human-readable text format instead of DER.
A time stamp response (TimeStampResp) consists of a response status and the
time stamp token itself (ContentInfo), if the token generation was
successful. The -reply command is for creating a time stamp response or
time stamp token based on a request and printing the response/token in
human-readable format. If -token_out is not specified the output is always
a time stamp response (TimeStampResp), otherwise it is a time stamp token
(ContentInfo).
-chain certs_file.pem
The collection of PEM certificates that will be included in the
response in addition to the signer certificate if the -cert option
was used for the request. This file is supposed to contain the
certificate chain for the signer certificate from its issuer
upwards. The -reply command does not build a certificate chain
automatically.
-config configfile
Specify an alternative configuration file.
-in response.tsr
Specify a previously created time stamp response (or time stamp
token, if -token_in is also specified) in DER format that will be
written to the output file. This option does not require a
request; it is useful, for example, to examine the content of a
response or token or to extract the time stamp token from a
response. If the input is a token and the output is a time stamp
response a default "granted" status info is added to the token.
-inkey private.pem
The signer private key of the TSA in PEM format. Overrides the
signer_key config file option.
-out response.tsr
The response is written to this file. The format and content of
the file depends on other options (see -text and -token_out). The
default is stdout.
-passin arg
The key password source.
-policy object_id
The default policy to use for the response. Either dotted OID
notation or OID names defined in the config file can be used. If
no policy is requested the TSA uses its own default policy.
-queryfile request.tsq
The file containing a DER-encoded time stamp request.
-section tsa_section
The config file section containing the settings for response
generation.
-signer tsa_cert.pem
The PEM signer certificate of the TSA. The TSA signing certificate
must have exactly one extended key usage assigned to it:
timeStamping. The extended key usage must also be critical,
otherwise the certificate is going to be refused. Overrides the
signer_cert variable of the config file.
-text Output in human-readable text format instead of DER.
-token_in
The input is a DER-encoded time stamp token (ContentInfo) instead
of a time stamp response (TimeStampResp).
-token_out
The output is a time stamp token (ContentInfo) instead of a time
stamp response (TimeStampResp).
The -verify command is for verifying if a time stamp response or time stamp
token is valid and matches a particular time stamp request or data file.
The -verify command does not use the configuration file.
-CAfile trusted_certs.pem
The file containing a set of trusted self-signed PEM CA
certificates. See verify for additional details. Either this
option or -CApath must be specified.
-CApath trusted_cert_path
The directory containing the trused CA certificates of the client.
See verify for additional details. Either this option or -CAfile
must be specified.
-data file_to_hash
The response or token must be verified against file_to_hash. The
file is hashed with the message digest algorithm specified in the
token. The -digest and -queryfile options must not be specified
with this one.
-digest digest_bytes
The response or token must be verified against the message digest
specified with this option. The number of bytes must match the
message digest algorithm specified in the token. The -data and
-queryfile options must not be specified with this one.
-in response.tsr
The time stamp response that needs to be verified, in DER format.
This option in mandatory.
-queryfile request.tsq
The original time stamp request, in DER format. The -data and
-digest options must not be specified with this one.
-token_in
The input is a DER-encoded time stamp token (ContentInfo) instead
of a time stamp response (TimeStampResp).
-untrusted cert_file.pem
Additional untrusted PEM certificates which may be needed when
building the certificate chain for the TSA's signing certificate.
This file must contain the TSA signing certificate and all
intermediate CA certificates unless the response includes them.
Options specified on the command line always override the settings in the
config file:
tsa section, default_tsa
This is the main section and it specifies the name of another
section that contains all the options for the -reply option. This
section can be overridden with the -section command line switch.
oid_file
See ca for a description.
oid_section
See ca for a description.
serial The file containing the hexadecimal serial number of the last time
stamp response created. This number is incremented by 1 for each
response. If the file does not exist at the time of response
generation a new file is created with serial number 1. This
parameter is mandatory.
signer_cert
TSA signing certificate, in PEM format. The same as the -signer
command line option.
certs A set of PEM-encoded certificates that need to be included in the
response. The same as the -chain command line option.
signer_key
The private key of the TSA, in PEM format. The same as the -inkey
command line option.
default_policy
The default policy to use when the request does not mandate any
policy. The same as the -policy command line option.
other_policies
Comma separated list of policies that are also acceptable by the
TSA and used only if the request explicitly specifies one of them.
digests
The list of message digest algorithms that the TSA accepts. At
least one algorithm must be specified. This parameter is
mandatory.
accuracy
The accuracy of the time source of the TSA in seconds, milliseconds
and microseconds. For example, secs:1, millisecs:500,
microsecs:100. If any of the components is missing, zero is
assumed for that field.
clock_precision_digits
The maximum number of digits, which represent the fraction of
seconds, that need to be included in the time field. The trailing
zeroes must be removed from the time, so there might actually be
fewer digits or no fraction of seconds at all. The maximum value
is 6; the default is 0.
ordering
If this option is yes, the responses generated by this TSA can
always be ordered, even if the time difference between two
responses is less than the sum of their accuracies. The default is
no.
tsa_name
Set this option to yes if the subject name of the TSA must be
included in the TSA name field of the response. The default is no.
ess_cert_id_chain
The SignedData objects created by the TSA always contain the
certificate identifier of the signing certificate in a signed
attribute (see RFC 2634, Enhanced Security Services). If this
option is set to yes and either the certs variable or the -chain
option is specified then the certificate identifiers of the chain
will also be included in the SigningCertificate signed attribute.
If this variable is set to no, only the signing certificate
identifier is included. The default is no.
VERIFY
openssl verify [-CAfile file] [-CApath directory] [-check_ss_sig]
[-crl_check] [-crl_check_all] [-explicit_policy]
[-extended_crl] [-help] [-ignore_critical] [-inhibit_any]
[-inhibit_map] [-issuer_checks] [-policy_check]
[-purpose purpose] [-untrusted file] [-verbose]
[-x509_strict] [certificates]
The verify command verifies certificate chains.
The options are as follows:
-check_ss_sig
Verify the signature on the self-signed root CA. This is disabled
by default because it doesn't add any security.
-CAfile file
A file of trusted certificates. The file should contain multiple
certificates in PEM format, concatenated together.
-CApath directory
A directory of trusted certificates. The certificates, or symbolic
links to them, should have names of the form hash.0, where hash is
the hashed certificate subject name (see the -hash option of the
x509 utility).
-crl_check
Check end entity certificate validity by attempting to look up a
valid CRL. If a valid CRL cannot be found an error occurs.
-crl_check_all
Check the validity of all certificates in the chain by attempting
to look up valid CRLs.
-explicit_policy
Set policy variable require-explicit-policy (RFC 3280).
-extended_crl
Enable extended CRL features such as indirect CRLs and alternate
CRL signing keys.
-help Print a usage message.
-ignore_critical
Ignore critical extensions instead of rejecting the certificate.
-inhibit_any
Set policy variable inhibit-any-policy (RFC 3280).
-inhibit_map
Set policy variable inhibit-policy-mapping (RFC 3280).
-issuer_checks
Print diagnostics relating to searches for the issuer certificate
of the current certificate showing why each candidate issuer
certificate was rejected. The presence of rejection messages does
not itself imply that anything is wrong: during the normal verify
process several rejections may take place.
-policy_check
Enable certificate policy processing.
-purpose purpose
The intended use for the certificate. Without this option no chain
verification will be done. Currently accepted uses are sslclient,
sslserver, nssslserver, smimesign, smimeencrypt, crlsign, any, and
ocsphelper.
-untrusted file
A file of untrusted certificates. The file should contain multiple
certificates.
-verbose
Print extra information about the operations being performed.
-x509_strict
Disable workarounds for broken certificates which have to be
disabled for strict X.509 compliance.
certificates
One or more PEM certificates to verify. If no certificate files
are included, an attempt is made to read a certificate from
standard input. If the first certificate filename begins with a
dash, use a lone dash to mark the last option.
The verify program uses the same functions as the internal SSL and S/MIME
verification, with one crucial difference: wherever possible an attempt is
made to continue after an error, whereas normally the verify operation
would halt on the first error. This allows all the problems with a
certificate chain to be determined.
The verify operation consists of a number of separate steps. Firstly a
certificate chain is built up starting from the supplied certificate and
ending in the root CA. It is an error if the whole chain cannot be built
up. The chain is built up by looking up the issuer's certificate of the
current certificate. If a certificate is found which is its own issuer, it
is assumed to be the root CA.
All certificates whose subject name matches the issuer name of the current
certificate are subject to further tests. The relevant authority key
identifier components of the current certificate (if present) must match
the subject key identifier (if present) and issuer and serial number of the
candidate issuer; in addition the keyUsage extension of the candidate
issuer (if present) must permit certificate signing.
The lookup first looks in the list of untrusted certificates and if no
match is found the remaining lookups are from the trusted certificates.
The root CA is always looked up in the trusted certificate list: if the
certificate to verify is a root certificate, then an exact match must be
found in the trusted list.
The second operation is to check every untrusted certificate's extensions
for consistency with the supplied purpose. If the -purpose option is not
included, then no checks are done. The supplied or "leaf" certificate must
have extensions compatible with the supplied purpose and all other
certificates must also be valid CA certificates. The precise extensions
required are described in more detail in the X509 section below.
The third operation is to check the trust settings on the root CA. The
root CA should be trusted for the supplied purpose. A certificate with no
trust settings is considered to be valid for all purposes.
The final operation is to check the validity of the certificate chain. The
validity period is checked against the current system time and the
notBefore and notAfter dates in the certificate. The certificate
signatures are also checked at this point.
If all operations complete successfully, the certificate is considered
valid. If any operation fails then the certificate is not valid. When a
verify operation fails, the output messages can be somewhat cryptic. The
general form of the error message is:
server.pem: /C=AU/ST=Queensland/O=CryptSoft Pty Ltd/CN=Test CA (1024-bit)
error 24 at 1 depth lookup:invalid CA certificate
The first line contains the name of the certificate being verified,
followed by the subject name of the certificate. The second line contains
the error number and the depth. The depth is the number of the certificate
being verified when a problem was detected starting with zero for the
certificate being verified itself, then 1 for the CA that signed the
certificate and so on. Finally a text version of the error number is
presented.
An exhaustive list of the error codes and messages is shown below; this
also includes the name of the error code as defined in the header file
<openssl/x509_vfy.h>. Some of the error codes are defined but never
returned: these are described as "unused".
0 X509_V_OK
The operation was successful.
2 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT
The issuer certificate of an untrusted certificate could not be
found.
3 X509_V_ERR_UNABLE_TO_GET_CRL
The CRL of a certificate could not be found.
4 X509_V_ERR_UNABLE_TO_DECRYPT_CERT_SIGNATURE
The certificate signature could not be decrypted. This means that
the actual signature value could not be determined rather than it not
matching the expected value. This is only meaningful for RSA keys.
5 X509_V_ERR_UNABLE_TO_DECRYPT_CRL_SIGNATURE
The CRL signature could not be decrypted. This means that the actual
signature value could not be determined rather than it not matching
the expected value. Unused.
6 X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY
The public key in the certificate SubjectPublicKeyInfo could not be
read.
7 X509_V_ERR_CERT_SIGNATURE_FAILURE
The signature of the certificate is invalid.
8 X509_V_ERR_CRL_SIGNATURE_FAILURE
The signature of the certificate is invalid.
9 X509_V_ERR_CERT_NOT_YET_VALID
The certificate is not yet valid: the notBefore date is after the
current time.
10 X509_V_ERR_CERT_HAS_EXPIRED
The certificate has expired; that is, the notAfter date is before the
current time.
11 X509_V_ERR_CRL_NOT_YET_VALID
The CRL is not yet valid.
12 X509_V_ERR_CRL_HAS_EXPIRED
The CRL has expired.
13 X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD
The certificate notBefore field contains an invalid time.
14 X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD
The certificate notAfter field contains an invalid time.
15 X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD
The CRL lastUpdate field contains an invalid time.
16 X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD
The CRL nextUpdate field contains an invalid time.
17 X509_V_ERR_OUT_OF_MEM
An error occurred trying to allocate memory. This should never
happen.
18 X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT
The passed certificate is self-signed and the same certificate cannot
be found in the list of trusted certificates.
19 X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN
The certificate chain could be built up using the untrusted
certificates but the root could not be found locally.
20 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY
The issuer certificate of a locally looked up certificate could not
be found. This normally means the list of trusted certificates is
not complete.
21 X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE
No signatures could be verified because the chain contains only one
certificate and it is not self-signed.
22 X509_V_ERR_CERT_CHAIN_TOO_LONG
The certificate chain length is greater than the supplied maximum
depth. Unused.
23 X509_V_ERR_CERT_REVOKED
The certificate has been revoked.
24 X509_V_ERR_INVALID_CA
A CA certificate is invalid. Either it is not a CA or its extensions
are not consistent with the supplied purpose.
25 X509_V_ERR_PATH_LENGTH_EXCEEDED
The basicConstraints pathlength parameter has been exceeded.
26 X509_V_ERR_INVALID_PURPOSE
The supplied certificate cannot be used for the specified purpose.
27 X509_V_ERR_CERT_UNTRUSTED
The root CA is not marked as trusted for the specified purpose.
28 X509_V_ERR_CERT_REJECTED
The root CA is marked to reject the specified purpose.
29 X509_V_ERR_SUBJECT_ISSUER_MISMATCH
The current candidate issuer certificate was rejected because its
subject name did not match the issuer name of the current
certificate. Only displayed when the -issuer_checks option is set.
30 X509_V_ERR_AKID_SKID_MISMATCH
The current candidate issuer certificate was rejected because its
subject key identifier was present and did not match the authority
key identifier current certificate. Only displayed when the
-issuer_checks option is set.
31 X509_V_ERR_AKID_ISSUER_SERIAL_MISMATCH
The current candidate issuer certificate was rejected because its
issuer name and serial number were present and did not match the
authority key identifier of the current certificate. Only displayed
when the -issuer_checks option is set.
32 X509_V_ERR_KEYUSAGE_NO_CERTSIGN
The current candidate issuer certificate was rejected because its
keyUsage extension does not permit certificate signing.
50 X509_V_ERR_APPLICATION_VERIFICATION
An application specific error. Unused.
VERSION
openssl version [-abdfopv]
The version command is used to print out version information about openssl.
The options are as follows:
-a All information: this is the same as setting all the other flags.
-b The date the current version of openssl was built.
-d OPENSSLDIR setting.
-f Compilation flags.
-o Option information: various options set when the library was built.
-p Platform setting.
-v The current openssl version.
X509
openssl x509 [-C] [-addreject arg] [-addtrust arg] [-alias] [-CA file]
[-CAcreateserial] [-CAform der | pem] [-CAkey file]
[-CAkeyform der | pem] [-CAserial file] [-certopt option]
[-checkend arg] [-clrext] [-clrreject] [-clrtrust] [-dates]
[-days arg] [-email] [-enddate] [-extensions section]
[-extfile file] [-fingerprint] [-hash] [-in file]
[-inform der | net | pem] [-issuer] [-issuer_hash]
[-issuer_hash_old] [-keyform der | pem] [-md5 | -sha1]
[-modulus] [-nameopt option] [-noout] [-ocsp_uri] [-ocspid]
[-out file] [-outform der | net | pem] [-passin arg] [-pubkey]
[-purpose] [-req] [-serial] [-set_serial n] [-setalias arg]
[-signkey file] [-startdate] [-subject] [-subject_hash]
[-subject_hash_old] [-text] [-trustout] [-x509toreq]
The x509 command is a multi-purpose certificate utility. It can be used to
display certificate information, convert certificates to various forms,
sign certificate requests like a "mini CA", or edit certificate trust
settings.
The following are x509 input, output, and general purpose options:
-in file
The input file to read from, or standard input if not specified.
-inform der | net | pem
The input format. Normally, the command will expect an X.509
certificate, but this can change if other options such as -req are
present.
-md5 | -sha1
The digest to use. This affects any signing or display option that
uses a message digest, such as the -fingerprint, -signkey, and -CA
options. If not specified, MD5 is used. SHA1 is always used with
DSA keys.
-out file
The output file to write to, or standard output if none is specified.
-outform der | net | pem
The output format.
-passin arg
The key password source.
The following are x509 display options:
-C Output the certificate in the form of a C source file.
-certopt option
Customise the output format used with -text, either using a list of
comma-separated options or by specifying -certopt multiple times.
The default behaviour is to print all fields. The options are as
follows:
ca_default Equivalent to no_issuer, no_pubkey, no_header,
no_version, no_sigdump, and no_signame.
compatible Equivalent to no output options at all.
ext_default Print unsupported certificate extensions.
ext_dump Hex dump unsupported extensions.
ext_error Print an error message for unsupported
certificate extensions.
ext_parse ASN.1 parse unsupported extensions.
no_aux Do not print certificate trust information.
no_extensions Do not print X509V3 extensions.
no_header Do not print header (Certificate and Data)
information.
no_issuer Do not print the issuer name.
no_pubkey Do not print the public key.
no_serial Do not print the serial number.
no_sigdump Do not give a hexadecimal dump of the
certificate signature.
no_signame Do not print the signature algorithm used.
no_subject Do not print the subject name.
no_validity Do not print the notBefore and notAfter
(validity) fields.
no_version Do not print the version number.
-dates
Print the start and expiry date of a certificate.
-email
Output the email addresses, if any.
-enddate
Print the expiry date of the certificate; that is, the notAfter date.
-fingerprint
Print the digest of the DER-encoded version of the whole certificate.
-hash
A synonym for -subject_hash.
-issuer
Print the issuer name.
-issuer_hash
Print the hash of the certificate issuer name.
-issuer_hash_old
Print the hash of the certificate issuer name using the older
algorithm as used by openssl versions before 1.0.0.
-modulus
Print the value of the modulus of the public key contained in the
certificate.
-nameopt option
Customise how the subject or issuer names are displayed, either using
a list of comma-separated options or by specifying -nameopt multiple
times. The default behaviour is to use the oneline format. The
options, which can be preceded by a dash to turn them off, are as
follows:
align
Align field values for a more readable output. Only usable
with sep_multiline.
compat
Use the old format, equivalent to specifying no options at all.
dn_rev
Reverse the fields of the DN, as required by RFC 2253. As a
side effect, this also reverses the order of multiple AVAs.
dump_all
Dump all fields. When used with dump_der, it allows the DER
encoding of the structure to be unambiguously determined.
dump_der
Any fields that need to be hexdumped are dumped using the DER
encoding of the field. Otherwise just the content octets will
be displayed. Both options use the RFC 2253 #XXXX... format.
dump_nostr
Dump non-character string types (for example OCTET STRING);
usually, non-character string types are displayed as though
each content octet represents a single character.
dump_unknown
Dump any field whose OID is not recognised by openssl.
esc_2253
Escape the "special" characters required by RFC 2253 in a field
that is “ ,+"<>;”. Additionally, ‘#’ is escaped at the
beginning of a string and a space character at the beginning or
end of a string.
esc_ctrl
Escape control characters. That is, those with ASCII values
less than 0x20 (space) and the delete (0x7f) character. They
are escaped using the RFC 2253 \XX notation (where XX are two
hex digits representing the character value).
esc_msb
Escape characters with the MSB set; that is, with ASCII values
larger than 127.
multiline
A multiline format. Equivalent to esc_ctrl, esc_msb,
sep_multiline, space_eq, lname, and align.
no_type
Do not attempt to interpret multibyte characters. That is,
content octets are merely dumped as though one octet represents
each character. This is useful for diagnostic purposes but
results in rather odd looking output.
nofname, sname, lname, oid
Alter how the field name is displayed: nofname does not display
the field at all; sname uses the short name form (CN for
commonName, for example); lname uses the long form. oid
represents the OID in numerical form and is useful for
diagnostic purpose.
oneline
A one line format which is more readable than RFC2253.
Equivalent to esc_2253, esc_ctrl, esc_msb, utf8, dump_nostr,
dump_der, use_quote, sep_comma_plus_spc, space_eq, and sname.
RFC2253
Displays names compatible with RFC 2253. Equivalent to
esc_2253, esc_ctrl, esc_msb, utf8, dump_nostr, dump_unknown,
dump_der, sep_comma_plus, dn_rev, and sname.
sep_comma_plus, sep_comma_plus_space, sep_semi_plus_space,
sep_multiline
Determine the field separators: the first character is between
RDNs and the second between multiple AVAs (multiple AVAs are
very rare and their use is discouraged). The options ending in
"space" additionally place a space after the separator to make
it more readable. sep_multiline uses a linefeed character for
the RDN separator and a spaced ‘+’ for the AVA separator, as
well as indenting the fields by four characters.
show_type
Show the type of the ASN.1 character string. The type precedes
the field contents. For example "BMPSTRING: Hello World".
space_eq
Place spaces round the ‘=’ character which follows the field
name.
use_quote
Escape some characters by surrounding the whole string with ‘"’
characters. Without the option, all escaping is done with the
‘\’ character.
utf8 Convert all strings to UTF8 format first, as required by RFC
2253. On a UTF8 compatible terminal, the use of this option
(and not setting esc_msb) may result in the correct display of
multibyte characters. Usually, multibyte characters larger
than 0xff are represented using the format \UXXXX for 16 bits
and \WXXXXXXXX for 32 bits, and any UTF8Strings are converted
to their character form first.
-noout
Do not output the encoded version of the request.
-ocsp_uri
Print the OCSP responder addresses, if any.
-ocspid
Print OCSP hash values for the subject name and public key.
-pubkey
Print the public key.
-serial
Print the certificate serial number.
-startdate
Print the start date of the certificate; that is, the notBefore date.
-subject
Print the subject name.
-subject_hash
Print the hash of the certificate subject name. This is used in
openssl to form an index to allow certificates in a directory to be
looked up by subject name.
-subject_hash_old
Print the hash of the certificate subject name using the older
algorithm as used by openssl versions before 1.0.0.
-text
Print the full certificate in text form.
A trusted certificate is a certificate which has several additional pieces
of information attached to it such as the permitted and prohibited uses of
the certificate and an alias. When a certificate is being verified at
least one certificate must be trusted. By default, a trusted certificate
must be stored locally and be a root CA. The following are x509 trust
settings options:
-addreject arg
Add a prohibited use. Accepts the same values as the -addtrust
option.
-addtrust arg
Add a trusted certificate use. Any object name can be used here, but
currently only clientAuth (SSL client use), serverAuth (SSL server
use), and emailProtection (S/MIME email) are used.
-alias
Output the certificate alias.
-clrreject
Clear all the prohibited or rejected uses of the certificate.
-clrtrust
Clear all the permitted or trusted uses of the certificate.
-purpose
Perform tests on the certificate extensions. The same code is used
when verifying untrusted certificates in chains, so this section is
useful if a chain is rejected by the verify code.
The basicConstraints extension CA flag is used to determine whether
the certificate can be used as a CA. If the CA flag is true, it is a
CA; if the CA flag is false, it is not a CA. All CAs should have the
CA flag set to true.
If the basicConstraints extension is absent, then the certificate is
considered to be a possible CA; other extensions are checked
according to the intended use of the certificate. A warning is given
in this case because the certificate should really not be regarded as
a CA. However it is allowed to be a CA to work around some broken
software.
If the certificate is a V1 certificate (and thus has no extensions)
and it is self-signed, it is also assumed to be a CA but a warning is
again given. This is to work around the problem of Verisign roots
which are V1 self-signed certificates.
If the keyUsage extension is present, then additional restraints are
made on the uses of the certificate. A CA certificate must have the
keyCertSign bit set if the keyUsage extension is present.
The extended key usage extension places additional restrictions on
the certificate uses. If this extension is present, whether critical
or not, the key can only be used for the purposes specified.
A complete description of each test is given below. The comments
about basicConstraints and keyUsage and V1 certificates above apply
to all CA certificates.
SSL Client
The extended key usage extension must be absent or include the
web client authentication OID. keyUsage must be absent or it
must have the digitalSignature bit set. The Netscape
certificate type must be absent or it must have the SSL client
bit set.
SSL Client CA
The extended key usage extension must be absent or include the
web client authentication OID. The Netscape certificate type
must be absent or it must have the SSL CA bit set: this is used
as a workaround if the basicConstraints extension is absent.
SSL Server
The extended key usage extension must be absent or include the
web server authentication and/or one of the SGC OIDs. keyUsage
must be absent or it must have the digitalSignature set, the
keyEncipherment set, or both bits set. The Netscape
certificate type must be absent or have the SSL server bit set.
SSL Server CA
The extended key usage extension must be absent or include the
web server authentication and/or one of the SGC OIDs. The
Netscape certificate type must be absent or the SSL CA bit must
be set: this is used as a workaround if the basicConstraints
extension is absent.
Netscape SSL Server
For Netscape SSL clients to connect to an SSL server; it must
have the keyEncipherment bit set if the keyUsage extension is
present. This isn't always valid because some cipher suites
use the key for digital signing. Otherwise it is the same as a
normal SSL server.
Common S/MIME Client Tests
The extended key usage extension must be absent or include the
email protection OID. The Netscape certificate type must be
absent or should have the S/MIME bit set. If the S/MIME bit is
not set in Netscape certificate type, then the SSL client bit
is tolerated as an alternative but a warning is shown: this is
because some Verisign certificates don't set the S/MIME bit.
S/MIME Signing
In addition to the common S/MIME client tests, the
digitalSignature bit must be set if the keyUsage extension is
present.
S/MIME Encryption
In addition to the common S/MIME tests, the keyEncipherment bit
must be set if the keyUsage extension is present.
S/MIME CA
The extended key usage extension must be absent or include the
email protection OID. The Netscape certificate type must be
absent or must have the S/MIME CA bit set: this is used as a
workaround if the basicConstraints extension is absent.
CRL Signing
The keyUsage extension must be absent or it must have the CRL
signing bit set.
CRL Signing CA
The normal CA tests apply, except the basicConstraints
extension must be present.
-setalias arg
Set the alias of the certificate, allowing the certificate to be
referred to using a nickname, such as "Steve's Certificate".
-trustout
Output a trusted certificate (the default if any trust settings are
modified). An ordinary or trusted certificate can be input, but by
default an ordinary certificate is output and any trust settings are
discarded.
The x509 utility can be used to sign certificates and requests: it can thus
behave like a mini CA. The following are x509 signing options:
-CA file
The CA certificate to be used for signing. When this option is
present, x509 behaves like a mini CA. The input file is signed by
the CA using this option; that is, its issuer name is set to the
subject name of the CA and it is digitally signed using the CA's
private key.
This option is normally combined with the -req option. Without the
-req option, the input is a certificate which must be self-signed.
-CAcreateserial
Create the CA serial number file if it does not exist instead of
generating an error. The file will contain the serial number ‘02’
and the certificate being signed will have ‘1’ as its serial number.
-CAform der | pem
The format of the CA certificate file. The default is pem.
-CAkey file
Set the CA private key to sign a certificate with. Otherwise it is
assumed that the CA private key is present in the CA certificate
file.
-CAkeyform der | pem
The format of the CA private key. The default is pem.
-CAserial file
Use the serial number in file to sign a certificate. The file should
consist of one line containing an even number of hex digits with the
serial number to use. After each use the serial number is
incremented and written out to the file again.
The default filename consists of the CA certificate file base name
with .srl appended. For example, if the CA certificate file is
called mycacert.pem, it expects to find a serial number file called
mycacert.srl.
-checkend arg
Check whether the certificate expires in the next arg seconds. If
so, exit with return value 1; otherwise exit with return value 0.
-clrext
Delete any extensions from a certificate. This option is used when a
certificate is being created from another certificate (for example
with the -signkey or the -CA options). Normally, all extensions are
retained.
-days arg
The number of days to make a certificate valid for. The default is
30 days.
-extensions section
The section to add certificate extensions from. If this option is
not specified, the extensions should either be contained in the
unnamed (default) section or the default section should contain a
variable called "extensions" which contains the section to use.
-extfile file
File containing certificate extensions to use. If not specified, no
extensions are added to the certificate.
-keyform der | pem
The format of the private key file used in the -signkey option.
-req Expect a certificate request on input instead of a certificate.
-set_serial n
The serial number to use. This option can be used with either the
-signkey or -CA options. If used in conjunction with the -CA option,
the serial number file (as specified by the -CAserial or
-CAcreateserial options) is not used.
The serial number can be decimal or hex (if preceded by ‘0x’).
Negative serial numbers can also be specified but their use is not
recommended.
-signkey file
Self-sign file using the supplied private key.
If the input file is a certificate, it sets the issuer name to the
subject name (i.e. makes it self-signed), changes the public key to
the supplied value, and changes the start and end dates. The start
date is set to the current time and the end date is set to a value
determined by the -days option. Any certificate extensions are
retained unless the -clrext option is supplied.
If the input is a certificate request, a self-signed certificate is
created using the supplied private key using the subject name in the
request.
-x509toreq
Convert a certificate into a certificate request. The -signkey
option is used to pass the required private key.
COMMON NOTATION
Several commands share a common syntax, as detailed below.
Password arguments, typically specified using -passin and -passout for
input and output passwords, allow passwords to be obtained from a variety
of sources. Both of these options take a single argument, described below.
If no password argument is given and a password is required, then the user
is prompted to enter one: this will typically be read from the current
terminal with echoing turned off.
pass:password The actual password is password. Since the password
is visible to utilities, this form should only be used
where security is not important.
env:var Obtain the password from the environment variable var.
Since the environment of other processes is visible,
this option should be used with caution.
file:path The first line of path is the password. If the same
path argument is supplied to -passin and -passout,
then the first line will be used for the input
password and the next line for the output password.
path need not refer to a regular file: it could, for
example, refer to a device or named pipe.
fd:number Read the password from the file descriptor number.
This can be used to send the data via a pipe, for
example.
stdin Read the password from standard input.
Input/output formats, typically specified using -inform and -outform,
indicate the format being read from or written to. The argument is case
insensitive.
der Distinguished Encoding Rules (DER) is a binary format.
net Insecure legacy format.
pem Privacy Enhanced Mail (PEM) is base64-encoded.
smime An SMIME format message.
txt Plain ASCII text.
ENVIRONMENT
The following environment variables affect the execution of openssl:
OPENSSL_CONF The location of the master configuration file.
FILES
/etc/ssl/ Default config directory for openssl.
/etc/ssl/lib/ Unused.
/etc/ssl/private/ Default private key directory.
/etc/ssl/openssl.cnf Default configuration file for openssl.
/etc/ssl/x509v3.cnf Default configuration file for x509 certificates.
SEE ALSO
acme-client(1), nc(1), openssl.cnf(5), x509v3.cnf(5), ssl(8), starttls(8)
STANDARDS
T. Dierks and C. Allen, The TLS Protocol Version 1.0, RFC 2246, January
1999.
M. Wahl, S. Killie, and T. Howes, Lightweight Directory Access Protocol
(v3): UTF-8 String Representation of Distinguished Names, RFC 2253,
December 1997.
B. Kaliski, PKCS #7: Cryptographic Message Syntax Version 1.5, RFC 2315,
March 1998.
R. Housley, W. Ford, W. Polk, and D. Solo, Internet X.509 Public Key
Infrastructure Certificate and CRL Profile, RFC 2459, January 1999.
M. Myers, R. Ankney, A. Malpani, S. Galperin, and C. Adams, X.509 Internet
Public Key Infrastructure Online Certificate Status Protocol – OCSP, RFC
2560, June 1999.
R. Housley, Cryptographic Message Syntax, RFC 2630, June 1999.
P. Chown, Advanced Encryption Standard (AES) Ciphersuites for Transport
Layer Security (TLS), RFC 3268, June 2002.
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