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OPENSSL(1ossl)                       OpenSSL                      OPENSSL(1ossl)


       openssl - OpenSSL command line program


       openssl command [ options ... ] [ parameters ... ]

       openssl no-XXX [ 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 program 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 and Message Authentication Codes
        o  Encryption and Decryption with Ciphers
        o  SSL/TLS Client and Server Tests
        o  Handling of S/MIME signed or encrypted mail
        o  Timestamp requests, generation and verification


       The openssl program provides a rich variety of commands (command in the
       "SYNOPSIS" above).  Each command can have many options and argument
       parameters, shown above as options and parameters.

       Detailed documentation and use cases for most standard subcommands are
       available (e.g., openssl-x509(1)). The subcommand openssl-list(1) may be
       used to list subcommands.

       The 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, or
       no-XXX itself.)

   Configuration Option
       Many commands use an external configuration file for some or all of their
       arguments and have a -config option to specify that file.  The default
       name of the file is openssl.cnf in the default certificate storage area,
       which can be determined from the openssl-version(1) command using the -d
       or -a option.  The environment variable OPENSSL_CONF can be used to
       specify a different file location or to disable loading a configuration
       (using the empty string).

       Among others, the configuration file can be used to load modules and to
       specify parameters for generating certificates and random numbers.  See
       config(5) for details.

   Standard Commands
           Parse an ASN.1 sequence.

       ca  Certificate Authority (CA) Management.

           Cipher Suite Description Determination.

       cms CMS (Cryptographic Message Syntax) command.

       crl Certificate Revocation List (CRL) Management.

           CRL to PKCS#7 Conversion.

           Message Digest calculation. MAC calculations are superseded by

           Generation and Management of Diffie-Hellman Parameters. Superseded by
           openssl-genpkey(1) and openssl-pkeyparam(1).

       dsa DSA Data Management.

           DSA Parameter Generation and Management. Superseded by
           openssl-genpkey(1) and openssl-pkeyparam(1).

       ec  EC (Elliptic curve) key processing.

           EC parameter manipulation and generation.

       enc Encryption, decryption, and encoding.

           Engine (loadable module) information and manipulation.

           Error Number to Error String Conversion.

           FIPS configuration installation.

           Generation of DSA Private Key from Parameters. Superseded by
           openssl-genpkey(1) and openssl-pkey(1).

           Generation of Private Key or Parameters.

           Generation of RSA Private Key. Superseded by openssl-genpkey(1).

           Display information about a command's options.

           Display diverse information built into the OpenSSL libraries.

       kdf Key Derivation Functions.

           List algorithms and features.

       mac Message Authentication Code Calculation.

           Create or examine a Netscape certificate sequence.

           Online Certificate Status Protocol command.

           Generation of hashed passwords.

           PKCS#12 Data Management.

           PKCS#7 Data Management.

           PKCS#8 format private key conversion command.

           Public and private key management.

           Public key algorithm parameter management.

           Public key algorithm cryptographic operation command.

           Compute prime numbers.

           Generate pseudo-random bytes.

           Create symbolic links to certificate and CRL files named by the hash

       req PKCS#10 X.509 Certificate Signing Request (CSR) Management.

       rsa RSA key management.

           RSA command for signing, verification, encryption, and decryption.
           Superseded by  openssl-pkeyutl(1).

           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.

           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.

           SSL Connection Timer.

           SSL Session Data Management.

           S/MIME mail processing.

           Algorithm Speed Measurement.

           SPKAC printing and generating command.

       srp Maintain SRP password file. This command is deprecated.

           Command to list and display certificates, keys, CRLs, etc.

       ts  Time Stamping Authority command.

           X.509 Certificate Verification.  See also the
           openssl-verification-options(1) manual page.

           OpenSSL Version Information.

           X.509 Certificate Data Management.

   Message Digest Commands
           BLAKE2b-512 Digest

           BLAKE2s-256 Digest

       md2 MD2 Digest

       md4 MD4 Digest

       md5 MD5 Digest

           MDC2 Digest

           RMD-160 Digest

           SHA-1 Digest

           SHA-2 224 Digest

           SHA-2 256 Digest

           SHA-2 384 Digest

           SHA-2 512 Digest

           SHA-3 224 Digest

           SHA-3 256 Digest

           SHA-3 384 Digest

           SHA-3 512 Digest

           SHA-3 SHAKE128 Digest

           SHA-3 SHAKE256 Digest

       sm3 SM3 Digest

   Encryption, Decryption, and Encoding Commands
       The following aliases provide convenient access to the most used
       encodings and ciphers.

       Depending on how OpenSSL was configured and built, not all ciphers listed
       here may be present. See openssl-enc(1) for more information.

       aes128, aes-128-cbc, aes-128-cfb, aes-128-ctr, aes-128-ecb, aes-128-ofb
           AES-128 Cipher

       aes192, aes-192-cbc, aes-192-cfb, aes-192-ctr, aes-192-ecb, aes-192-ofb
           AES-192 Cipher

       aes256, aes-256-cbc, aes-256-cfb, aes-256-ctr, aes-256-ecb, aes-256-ofb
           AES-256 Cipher

       aria128, aria-128-cbc, aria-128-cfb, aria-128-ctr, aria-128-ecb,
           Aria-128 Cipher

       aria192, aria-192-cbc, aria-192-cfb, aria-192-ctr, aria-192-ecb,
           Aria-192 Cipher

       aria256, aria-256-cbc, aria-256-cfb, aria-256-ctr, aria-256-ecb,
           Aria-256 Cipher

           Base64 Encoding

       bf, bf-cbc, bf-cfb, bf-ecb, bf-ofb
           Blowfish Cipher

       camellia128, camellia-128-cbc, camellia-128-cfb, camellia-128-ctr,
       camellia-128-ecb, camellia-128-ofb
           Camellia-128 Cipher

       camellia192, camellia-192-cbc, camellia-192-cfb, camellia-192-ctr,
       camellia-192-ecb, camellia-192-ofb
           Camellia-192 Cipher

       camellia256, camellia-256-cbc, camellia-256-cfb, camellia-256-ctr,
       camellia-256-ecb, camellia-256-ofb
           Camellia-256 Cipher

       cast, cast-cbc
           CAST Cipher

       cast5-cbc, cast5-cfb, cast5-ecb, cast5-ofb
           CAST5 Cipher

           Chacha20 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

       seed, seed-cbc, seed-cfb, seed-ecb, seed-ofb
           SEED Cipher

       sm4, sm4-cbc, sm4-cfb, sm4-ctr, sm4-ecb, sm4-ofb
           SM4 Cipher


       Details of which options are available depend on the specific command.
       This section describes some common options with common behavior.

   Common Options
           Provides a terse summary of all options.  If an option takes an
           argument, the "type" of argument is also given.

       --  This terminates the list of options. It is mostly useful if any
           filename parameters start with a minus sign:

            openssl verify [flags...] -- -cert1.pem...

   Format Options
       See openssl-format-options(1) for manual page.

   Pass Phrase Options
       See the openssl-passphrase-options(1) manual page.

   Random State Options
       Prior to OpenSSL 1.1.1, it was common for applications to store
       information about the state of the random-number generator in a file that
       was loaded at startup and rewritten upon exit. On modern operating
       systems, this is generally no longer necessary as OpenSSL will seed
       itself from a trusted entropy source provided by the operating system.
       These flags are still supported for special platforms or circumstances
       that might require them.

       It is generally an error to use the same seed file more than once and
       every use of -rand should be paired with -writerand.

       -rand files
           A file or files containing random data used to seed the random number
           generator.  Multiple files can be specified separated by an OS-
           dependent character.  The separator is ";" for MS-Windows, "," for
           OpenVMS, and ":" for all others. Another way to specify multiple
           files is to repeat this flag with different filenames.

       -writerand file
           Writes the seed data to the specified file upon exit.  This file can
           be used in a subsequent command invocation.

   Certificate Verification Options
       See the openssl-verification-options(1) manual page.

   Name Format Options
       See the openssl-namedisplay-options(1) manual page.

   TLS Version Options
       Several commands use SSL, TLS, or DTLS. By default, the commands use TLS
       and clients will offer the lowest and highest protocol version they
       support, and servers will pick the highest version that the client offers
       that is also supported by the server.

       The options below can be used to limit which protocol versions are used,
       and whether TCP (SSL and TLS) or UDP (DTLS) is used.  Note that not all
       protocols and flags may be available, depending on how OpenSSL was built.

       -ssl3, -tls1, -tls1_1, -tls1_2, -tls1_3, -no_ssl3, -no_tls1, -no_tls1_1,
       -no_tls1_2, -no_tls1_3
           These options require or disable the use of the specified SSL or TLS
           protocols.  When a specific TLS version is required, only that
           version will be offered or accepted.  Only one specific protocol can
           be given and it cannot be combined with any of the no_ options.

       -dtls, -dtls1, -dtls1_2
           These options specify to use DTLS instead of DLTS. With -dtls,
           clients will negotiate any supported DTLS protocol version.  Use the
           -dtls1 or -dtls1_2 options to support only DTLS1.0 or DTLS1.2,

   Engine Options
       -engine id
           Load the engine identified by id and use all the methods it
           implements (algorithms, key storage, etc.), unless specified
           otherwise in the command-specific documentation or it is configured
           to do so, as described in "Engine Configuration" in config(5).

           The engine will be used for key ids specified with -key and similar
           options when an option like -keyform engine is given.

           A special case is the "loader_attic" engine, which is meant just for
           internal OpenSSL testing purposes and supports loading keys,
           parameters, certificates, and CRLs from files.  When this engine is
           used, files with such credentials are read via this engine.  Using
           the "file:" schema is optional; a plain file (path) name will do.

       Options specifying keys, like -key and similar, can use the generic
       OpenSSL engine key loading URI scheme "org.openssl.engine:" to retrieve
       private keys and public keys.  The URI syntax is as follows, in
       simplified form:


       Where "{engineid}" is the identity/name of the engine, and "{keyid}" is a
       key identifier that's acceptable by that engine.  For example, when using
       an engine that interfaces against a PKCS#11 implementation, the generic
       key URI would be something like this (this happens to be an example for
       the PKCS#11 engine that's part of OpenSC):

           -key org.openssl.engine:pkcs11:label_some-private-key

       As a third possibility, for engines and providers that have implemented
       their own OSSL_STORE_LOADER(3), "org.openssl.engine:" should not be
       necessary.  For a PKCS#11 implementation that has implemented such a
       loader, the PKCS#11 URI as defined in RFC 7512 should be possible to use

           -key pkcs11:object=some-private-key;pin-value=1234

   Provider Options
       -provider name
           Load and initialize the provider identified by name. The name can be
           also a path to the provider module. In that case the provider name
           will be the specified path and not just the provider module name.
           Interpretation of relative paths is platform specific. The configured
           "MODULESDIR" path, OPENSSL_MODULES environment variable, or the path
           specified by -provider-path is prepended to relative paths.  See
           provider(7) for a more detailed description.

       -provider-path path
           Specifies the search path that is to be used for looking for
           providers.  Equivalently, the OPENSSL_MODULES environment variable
           may be set.

       -propquery propq
           Specifies the property query clause to be used when fetching
           algorithms from the loaded providers.  See property(7) for a more
           detailed description.


       The OpenSSL library can be take some configuration parameters from the
       environment.  Some of these variables are listed below.  For information
       about specific commands, see openssl-engine(1), openssl-rehash(1), and

       For information about the use of environment variables in configuration,
       see "ENVIRONMENT" in config(5).

       For information about querying or specifying CPU architecture flags, see
       OPENSSL_ia32cap(3), and OPENSSL_s390xcap(3).

       For information about all environment variables used by the OpenSSL
       libraries, see openssl-env(7).

           Enable tracing output of OpenSSL library, by name.  This output will
           only make sense if you know OpenSSL internals well.  Also, it might
           not give you any output at all if OpenSSL was built without tracing

           The value is a comma separated list of names, with the following

               Traces the OpenSSL trace API itself.

               Traces OpenSSL library initialization and cleanup.

           TLS Traces the TLS/SSL protocol.

               Traces the ciphers used by the TLS/SSL protocol.

               Show details about provider and engine configuration.

               The function that is used by RSA, DSA (etc) code to select
               registered ENGINEs, cache defaults and functional references
               (etc), will generate debugging summaries.

               Reference counts in the ENGINE structure will be monitored with a
               line of generated for each change.

               Traces PKCS#5 v2 key generation.

               Traces PKCS#12 key generation.

               Traces PKCS#12 decryption.

               Generates the complete policy tree at various points during X.509
               v3 policy evaluation.

               Traces BIGNUM context operations.

           CMP Traces CMP client and server activity.

               Traces STORE operations.

               Traces decoder operations.

               Traces encoder operations.

               Traces decrementing certain ASN.1 structure references.

               HTTP client diagnostics


       openssl-asn1parse(1), openssl-ca(1), openssl-ciphers(1), openssl-cms(1),
       openssl-crl(1), openssl-crl2pkcs7(1), openssl-dgst(1),
       openssl-dhparam(1), openssl-dsa(1), openssl-dsaparam(1), openssl-ec(1),
       openssl-ecparam(1), openssl-enc(1), openssl-engine(1), openssl-errstr(1),
       openssl-gendsa(1), openssl-genpkey(1), openssl-genrsa(1), openssl-kdf(1),
       openssl-list(1), openssl-mac(1), openssl-nseq(1), openssl-ocsp(1),
       openssl-passwd(1), openssl-pkcs12(1), openssl-pkcs7(1), openssl-pkcs8(1),
       openssl-pkey(1), openssl-pkeyparam(1), openssl-pkeyutl(1),
       openssl-prime(1), openssl-rand(1), openssl-rehash(1), openssl-req(1),
       openssl-rsa(1), openssl-rsautl(1), openssl-s_client(1),
       openssl-s_server(1), openssl-s_time(1), openssl-sess_id(1),
       openssl-smime(1), openssl-speed(1), openssl-spkac(1), openssl-srp(1),
       openssl-storeutl(1), openssl-ts(1), openssl-verify(1),
       openssl-version(1), openssl-x509(1), config(5), crypto(7),
       openssl-env(7).  ssl(7), x509v3_config(5)


       The list -XXX-algorithms options were added in OpenSSL 1.0.0; For notes
       on the availability of other commands, see their individual manual pages.

       The -issuer_checks option is deprecated as of OpenSSL 1.1.0 and is
       silently ignored.

       The -xcertform and -xkeyform options are obsolete since OpenSSL 3.0 and
       have no effect.

       The interactive mode, which could be invoked by running "openssl" with no
       further arguments, was removed in OpenSSL 3.0, and running that program
       with no arguments is now equivalent to "openssl help".


       Copyright 2000-2022 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the Apache License 2.0 (the "License").  You may not use
       this file except in compliance with the License.  You can obtain a copy
       in the file LICENSE in the source distribution or at

3.1.0                              2023-03-14                     OPENSSL(1ossl)

openssl 3.1.0 - Generated Wed Mar 15 15:58:11 CDT 2023
© 2000-2023
Individual documents may contain additional copyright information.