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OPENSSL

Section: OpenSSL (1)
Updated: 2007-09-17
Index Return to Main Contents
 

NAME

openssl - OpenSSL command line tool  

SYNOPSIS

openssl command [ command_opts ] [ command_args ]

openssl [ list-standard-commands | list-message-digest-commands | list-cipher-commands ]

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 of RSA, DH and DSA key parameters
 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

 

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-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.
crl
Certificate Revocation List (CRL) Management.
crl2pkcs7
CRL to PKCS#7 Conversion.
dgst
Message Digest Calculation.
dh
Diffie-Hellman Parameter Management. Obsoleted by dhparam.
dsa
DSA Data Management.
dsaparam
DSA Parameter Generation.
enc
Encoding with Ciphers.
errstr
Error Number to Error String Conversion.
dhparam
Generation and Management of Diffie-Hellman Parameters.
gendh
Generation of Diffie-Hellman Parameters. Obsoleted by dhparam.
gendsa
Generation of DSA Parameters.
genrsa
Generation of RSA Parameters.
ocsp
Online Certificate Status Protocol utility.
passwd
Generation of hashed passwords.
pkcs12
PKCS#12 Data Management.
pkcs7
PKCS#7 Data Management.
rand
Generate pseudo-random bytes.
req
X.509 Certificate Signing Request (CSR) Management.
rsa
RSA Data Management.
rsautl
RSA utility for signing, verification, encryption, and decryption.
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.
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), 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)  

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 no-XXX pseudo-commands were added in OpenSSL 0.9.5a. For notes on the availability of other commands, see their individual manual pages.


 

Index

NAME
SYNOPSIS
DESCRIPTION
COMMAND SUMMARY
STANDARD COMMANDS
MESSAGE DIGEST COMMANDS
ENCODING AND CIPHER COMMANDS
PASS PHRASE ARGUMENTS
SEE ALSO
HISTORY




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