openssl(1ssl)
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-XXX [ arbitrary options ]
DESCRIPTION
OpenSSL is a cryptography toolkit implementing the Secure Sockets Layer
(SSL v2/v3) and Transport Layer Security (TLS v1) network protocols and
related cryptography standards required by them.
The openssl program is a command line tool for using the various
cryptography functions of OpenSSL's crypto library from the shell. It
can be used for
o Creation and management of private keys, public keys and parameters
o Public key cryptographic operations
o Creation of X.509 certificates, CSRs and CRLs
o Calculation of Message Digests
o Encryption and Decryption with Ciphers
o SSL/TLS Client and Server Tests
o Handling of S/MIME signed or encrypted mail
o Time Stamp requests, generation and verification
COMMAND SUMMARY
The openssl program provides a rich variety of commands (command in the
SYNOPSIS above), each of which often has a wealth of options and
arguments (command_opts and command_args in the SYNOPSIS).
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-XXX tests whether a command of the specified name
is available. If no command named XXX exists, it returns 0 (success)
and prints no-XXX; otherwise it returns 1 and prints XXX. 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. (no-XXX is not able to detect pseudo-commands such as
quit, list-...-commands, or no-XXX itself.)
STANDARD COMMANDS
asn1parse Parse an ASN.1 sequence.
ca Certificate Authority (CA) Management.
ciphers Cipher Suite Description Determination.
cms CMS (Cryptographic Message Syntax) utility
crl Certificate Revocation List (CRL) Management.
crl2pkcs7 CRL to PKCS#7 Conversion.
dgst Message Digest Calculation.
dh Diffie-Hellman Parameter Management. Obsoleted by dhparam.
dhparam Generation and Management of Diffie-Hellman Parameters.
Superseded by genpkey and pkeyparam
dsa DSA Data Management.
dsaparam DSA Parameter Generation and Management. Superseded by
genpkey and pkeyparam
ec EC (Elliptic curve) key processing
ecparam EC parameter manipulation and generation
enc Encoding with Ciphers.
engine Engine (loadble module) information and manipulation.
errstr Error Number to Error String Conversion.
gendh Generation of Diffie-Hellman Parameters. Obsoleted by
dhparam.
gendsa Generation of DSA Private Key from Parameters. Superseded by
genpkey and pkey
genpkey Generation of Private Key or Parameters.
genrsa Generation of RSA Private Key. Superceded by genpkey.
nseq Create or examine a netscape certificate sequence
ocsp Online Certificate Status Protocol utility.
passwd Generation of hashed passwords.
pkcs12 PKCS#12 Data Management.
pkcs7 PKCS#7 Data Management.
pkey Public and private key management.
pkeyparam Public key algorithm parameter management.
pkeyutl Public key algorithm cryptographic operation utility.
rand Generate pseudo-random bytes.
req PKCS#10 X.509 Certificate Signing Request (CSR) Management.
rsa RSA key management.
rsautl RSA utility for signing, verification, encryption, and
decryption. Superseded by pkeyutl
s_client This implements a generic SSL/TLS client which can establish
a transparent connection to a remote server speaking SSL/TLS.
It's intended for testing purposes only and provides only
rudimentary interface functionality but internally uses
mostly all functionality of the OpenSSL ssl library.
s_server This implements a generic SSL/TLS server which accepts
connections from remote clients speaking SSL/TLS. It's
intended for testing purposes only and provides only
rudimentary interface functionality but internally uses
mostly all functionality of the OpenSSL ssl library. It
provides both an own command line oriented protocol for
testing SSL functions and a simple HTTP response facility to
emulate an SSL/TLS-aware webserver.
s_time SSL Connection Timer.
sess_id SSL Session Data Management.
smime S/MIME mail processing.
speed Algorithm Speed Measurement.
spkac SPKAC printing and generating utility
ts Time Stamping Authority tool (client/server)
verify X.509 Certificate Verification.
version OpenSSL Version Information.
x509 X.509 Certificate Data Management.
MESSAGE DIGEST COMMANDS
md2 MD2 Digest
md5 MD5 Digest
mdc2 MDC2 Digest
rmd160 RMD-160 Digest
sha SHA Digest
sha1 SHA-1 Digest
sha224 SHA-224 Digest
sha256 SHA-256 Digest
sha384 SHA-384 Digest
sha512 SHA-512 Digest
ENCODING AND CIPHER COMMANDS
base64 Base64 Encoding
bf bf-cbc bf-cfb bf-ecb bf-ofb
Blowfish Cipher
cast cast-cbc
CAST Cipher
cast5-cbc cast5-cfb cast5-ecb cast5-ofb
CAST5 Cipher
des des-cbc des-cfb des-ecb des-ede des-ede-cbc des-ede-cfb des-ede-ofb
des-ofb
DES Cipher
des3 desx des-ede3 des-ede3-cbc des-ede3-cfb des-ede3-ofb
Triple-DES Cipher
idea idea-cbc idea-cfb idea-ecb idea-ofb
IDEA Cipher
rc2 rc2-cbc rc2-cfb rc2-ecb rc2-ofb
RC2 Cipher
rc4 RC4 Cipher
rc5 rc5-cbc rc5-cfb rc5-ecb rc5-ofb
RC5 Cipher
PASS PHRASE ARGUMENTS
Several commands accept password arguments, typically using -passin and
-passout for input and output passwords respectively. These allow the
password to be obtained from a variety of sources. Both of these
options take a single argument whose format is 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 (like 'ps' under Unix) 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 on certain
platforms (e.g. ps under certain Unix OSes) this option
should be used with caution.
file:pathname
the first line of pathname is the password. If the same
pathname argument is supplied to -passin and -passout
arguments then the first line will be used for the input
password and the next line for the output password. pathname
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.
SEE ALSO
asn1parse(1), ca(1), config(5), crl(1), crl2pkcs7(1), dgst(1), dhparam(1), dsa(1), dsaparam(1), enc(1), gendsa(1), genpkey(1), genrsa(1), nseq(1), openssl(1), passwd(1), pkcs12(1), pkcs7(1), pkcs8(1), rand(1), req(1), rsa(1), rsautl(1), s_client(1), s_server(1), s_time(1), smime(1), spkac(1), verify(1), version(1), x509(1), crypto(3), ssl(3), x509v3_config(5)
HISTORY
The openssl(1) document appeared in OpenSSL 0.9.2. The list-XXX-commands pseudo-commands were added in OpenSSL 0.9.3; The list-XXX-algorithms pseudo-commands were added in OpenSSL 1.0.0; the no-XXX pseudo-commands were added in OpenSSL 0.9.5a. For notes on the availability of other commands, see their individual manual pages.
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