openssl - OpenSSL command line tool


   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 ]


   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


   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.)

   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

   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.

   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

   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 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


   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.

             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.

             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.


   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)


   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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