5 openssl - OpenSSL command line tool
11 [ I<command_opts> ... ]
12 [ I<command_args> ... ]
16 B<-standard-commands> |
19 B<-cipher-algorithms> |
20 B<-digest-algorithms> |
22 B<-public-key-algorithms>
24 B<openssl> B<no->I<XXX> [ I<arbitrary options> ]
28 OpenSSL is a cryptography toolkit implementing the Secure Sockets Layer (SSL
29 v2/v3) and Transport Layer Security (TLS v1) network protocols and related
30 cryptography standards required by them.
32 The B<openssl> program is a command line tool for using the various
33 cryptography functions of OpenSSL's B<crypto> library from the shell.
36 o Creation and management of private keys, public keys and parameters
37 o Public key cryptographic operations
38 o Creation of X.509 certificates, CSRs and CRLs
39 o Calculation of Message Digests and Message Authentication Codes
40 o Encryption and Decryption with Ciphers
41 o SSL/TLS Client and Server Tests
42 o Handling of S/MIME signed or encrypted mail
43 o Timestamp requests, generation and verification
45 =head1 COMMAND SUMMARY
47 The B<openssl> program provides a rich variety of sub-commands (I<command> in
48 the SYNOPSIS above), each of which often has a wealth of options and arguments
49 (I<command_opts> and I<command_args> in the SYNOPSIS).
51 Detailed documentation and use cases for most standard subcommands are available
52 (e.g., L<x509(1)> or L<openssl-x509(1)>).
54 Many commands use an external configuration file for some or all of their
55 arguments and have a B<-config> option to specify that file.
56 The environment variable B<OPENSSL_CONF> can be used to specify
57 the location of the file.
58 If the environment variable is not specified, then the file is named
59 F<openssl.cnf> in the default certificate storage area, whose value
60 depends on the configuration flags specified when the OpenSSL
63 The list options B<-standard-commands>, B<-digest-commands>,
64 and B<-cipher-commands> output a list (one entry per line) of the names
65 of all standard commands, message digest commands, or cipher commands,
66 respectively, that are available.
68 The list parameters B<-cipher-algorithms>, B<-digest-algorithms>,
69 and B<-mac-algorithms> list all cipher, message digest, and message
70 authentication code names, one entry per line. Aliases are listed as:
74 The list parameter B<-public-key-algorithms> lists all supported public
77 The command B<no->I<XXX> tests whether a command of the
78 specified name is available. If no command named I<XXX> exists, it
79 returns 0 (success) and prints B<no->I<XXX>; otherwise it returns 1
80 and prints I<XXX>. In both cases, the output goes to B<stdout> and
81 nothing is printed to B<stderr>. Additional command line arguments
82 are always ignored. Since for each cipher there is a command of the
83 same name, this provides an easy way for shell scripts to test for the
84 availability of ciphers in the B<openssl> program. (B<no->I<XXX> is
85 not able to detect pseudo-commands such as B<quit>,
86 B<list>, or B<no->I<XXX> itself.)
88 =head2 Standard Sub-commands
94 Parse an ASN.1 sequence.
98 Certificate Authority (CA) Management.
102 Cipher Suite Description Determination.
106 CMS (Cryptographic Message Syntax) utility.
110 Certificate Revocation List (CRL) Management.
114 CRL to PKCS#7 Conversion.
118 Message Digest calculation. MAC calculations are superseded by
123 Diffie-Hellman Parameter Management.
124 Obsoleted by L<openssl-dhparam(1)>.
128 Generation and Management of Diffie-Hellman Parameters. Superseded by
129 L<openssl-genpkey(1)> and L<openssl-pkeyparam(1)>.
137 DSA Parameter Generation and Management. Superseded by
138 L<openssl-genpkey(1)> and L<openssl-pkeyparam(1)>.
142 EC (Elliptic curve) key processing.
146 EC parameter manipulation and generation.
150 Encoding with Ciphers.
154 Engine (loadable module) information and manipulation.
158 Error Number to Error String Conversion.
162 Generation of Diffie-Hellman Parameters.
163 Obsoleted by L<openssl-dhparam(1)>.
167 Generation of DSA Private Key from Parameters. Superseded by
168 L<openssl-genpkey(1)> and L<openssl-pkey(1)>.
172 Generation of Private Key or Parameters.
176 Generation of RSA Private Key. Superseded by L<openssl-genpkey(1)>.
180 Display diverse information built into the OpenSSL libraries.
184 Key Derivation Functions.
188 Message Authentication Code Calculation.
192 Create or examine a Netscape certificate sequence.
196 Online Certificate Status Protocol utility.
200 Generation of hashed passwords.
204 PKCS#12 Data Management.
208 PKCS#7 Data Management.
212 PKCS#8 format private key conversion tool.
216 Public and private key management.
220 Public key algorithm parameter management.
224 Public key algorithm cryptographic operation utility.
228 Compute prime numbers.
232 Generate pseudo-random bytes.
236 Create symbolic links to certificate and CRL files named by the hash values.
240 PKCS#10 X.509 Certificate Signing Request (CSR) Management.
248 RSA utility for signing, verification, encryption, and decryption. Superseded
249 by L<openssl-pkeyutl(1)>.
253 This implements a generic SSL/TLS client which can establish a transparent
254 connection to a remote server speaking SSL/TLS. It's intended for testing
255 purposes only and provides only rudimentary interface functionality but
256 internally uses mostly all functionality of the OpenSSL B<ssl> library.
260 This implements a generic SSL/TLS server which accepts connections from remote
261 clients speaking SSL/TLS. It's intended for testing purposes only and provides
262 only rudimentary interface functionality but internally uses mostly all
263 functionality of the OpenSSL B<ssl> library. It provides both an own command
264 line oriented protocol for testing SSL functions and a simple HTTP response
265 facility to emulate an SSL/TLS-aware webserver.
269 SSL Connection Timer.
273 SSL Session Data Management.
277 S/MIME mail processing.
281 Algorithm Speed Measurement.
285 SPKAC printing and generating utility.
289 Maintain SRP password file.
293 Utility to list and display certificates, keys, CRLs, etc.
297 Time Stamping Authority tool (client/server).
301 X.509 Certificate Verification.
305 OpenSSL Version Information.
309 X.509 Certificate Data Management.
313 =head2 Message Digest Commands
383 SHA-3 SHAKE128 Digest
387 SHA-3 SHAKE256 Digest
395 =head2 Encoding and Cipher Commands
397 The following aliases provide convenient access to the most used encodings
400 Depending on how OpenSSL was configured and built, not all ciphers listed
401 here may be present. See L<openssl-enc(1)> for more information and command
406 =item B<aes128>, B<aes-128-cbc>, B<aes-128-cfb>, B<aes-128-ctr>, B<aes-128-ecb>, B<aes-128-ofb>
410 =item B<aes192>, B<aes-192-cbc>, B<aes-192-cfb>, B<aes-192-ctr>, B<aes-192-ecb>, B<aes-192-ofb>
414 =item B<aes256>, B<aes-256-cbc>, B<aes-256-cfb>, B<aes-256-ctr>, B<aes-256-ecb>, B<aes-256-ofb>
418 =item B<aria128>, B<aria-128-cbc>, B<aria-128-cfb>, B<aria-128-ctr>, B<aria-128-ecb>, B<aria-128-ofb>
422 =item B<aria192>, B<aria-192-cbc>, B<aria-192-cfb>, B<aria-192-ctr>, B<aria-192-ecb>, B<aria-192-ofb>
426 =item B<aria256>, B<aria-256-cbc>, B<aria-256-cfb>, B<aria-256-ctr>, B<aria-256-ecb>, B<aria-256-ofb>
434 =item B<bf>, B<bf-cbc>, B<bf-cfb>, B<bf-ecb>, B<bf-ofb>
438 =item B<camellia128>, B<camellia-128-cbc>, B<camellia-128-cfb>, B<camellia-128-ctr>, B<camellia-128-ecb>, B<camellia-128-ofb>
442 =item B<camellia192>, B<camellia-192-cbc>, B<camellia-192-cfb>, B<camellia-192-ctr>, B<camellia-192-ecb>, B<camellia-192-ofb>
446 =item B<camellia256>, B<camellia-256-cbc>, B<camellia-256-cfb>, B<camellia-256-ctr>, B<camellia-256-ecb>, B<camellia-256-ofb>
450 =item B<cast>, B<cast-cbc>
454 =item B<cast5-cbc>, B<cast5-cfb>, B<cast5-ecb>, B<cast5-ofb>
462 =item B<des>, B<des-cbc>, B<des-cfb>, B<des-ecb>, B<des-ede>, B<des-ede-cbc>, B<des-ede-cfb>, B<des-ede-ofb>, B<des-ofb>
466 =item B<des3>, B<desx>, B<des-ede3>, B<des-ede3-cbc>, B<des-ede3-cfb>, B<des-ede3-ofb>
470 =item B<idea>, B<idea-cbc>, B<idea-cfb>, B<idea-ecb>, B<idea-ofb>
474 =item B<rc2>, B<rc2-cbc>, B<rc2-cfb>, B<rc2-ecb>, B<rc2-ofb>
482 =item B<rc5>, B<rc5-cbc>, B<rc5-cfb>, B<rc5-ecb>, B<rc5-ofb>
486 =item B<seed>, B<seed-cbc>, B<seed-cfb>, B<seed-ecb>, B<seed-ofb>
490 =item B<sm4>, B<sm4-cbc>, B<sm4-cfb>, B<sm4-ctr>, B<sm4-ecb>, B<sm4-ofb>
498 Details of which options are available depend on the specific command.
499 This section describes some common options with common behavior.
501 =head2 Common Options
507 Provides a terse summary of all options.
508 If an option takes an argument, the "type" of argument is also given.
512 This terminates the list of options. It is mostly useful if any filename
513 parameters start with a minus sign:
515 openssl verify [flags...] -- -cert1.pem...
519 =head2 Pass Phrase Options
521 Several commands accept password arguments, typically using B<-passin>
522 and B<-passout> for input and output passwords respectively. These allow
523 the password to be obtained from a variety of sources. Both of these
524 options take a single argument whose format is described below. If no
525 password argument is given and a password is required then the user is
526 prompted to enter one: this will typically be read from the current
527 terminal with echoing turned off.
529 Note that character encoding may be relevant, please see
530 L<passphrase-encoding(7)>.
534 =item B<pass:>I<password>
536 The actual password is I<password>. Since the password is visible
537 to utilities (like 'ps' under Unix) this form should only be used
538 where security is not important.
542 Obtain the password from the environment variable I<var>. Since
543 the environment of other processes is visible on certain platforms
544 (e.g. ps under certain Unix OSes) this option should be used with caution.
546 =item B<file:>I<pathname>
548 The first line of I<pathname> is the password. If the same I<pathname>
549 argument is supplied to B<-passin> and B<-passout> arguments then the first
550 line will be used for the input password and the next line for the output
551 password. I<pathname> need not refer to a regular file: it could for example
552 refer to a device or named pipe.
554 =item B<fd:>I<number>
556 Read the password from the file descriptor I<number>. This can be used to
557 send the data via a pipe for example.
561 Read the password from standard input.
565 =head2 Trusted Certificate Options
567 Part of validating a certificate includes verifying that the chain of CA's
568 can be traced up to an existing trusted root. The following options specify
569 how to list the trusted roots, also known as trust anchors. A collection
570 of trusted roots is called a I<trust store>.
572 Note that OpenSSL does not provide a default set of trust anchors. Many
573 Linux distributions include a system default and configure OpenSSL to point
574 to that. Mozilla maintains an influential trust store that can be found at
575 L<https://www.mozilla.org/en-US/about/governance/policies/security-group/certs/>.
579 =item B<-CAfile> I<file>
581 Load the specified file which contains one or more PEM-format certificates
582 of CA's that are trusted.
586 Do not load the default file of trusted certificates.
588 =item B<-CApath> I<dir>
590 Use the specified directory as a list of trust certificates. That is,
591 files should be named with the hash of the X.509 SubjectName of each
592 certificate. This is so that the library can extract the IssuerName,
593 hash it, and directly lookup the file to get the issuer certificate.
594 See L<openssl-rehash(1)> for information on creating this type of directory.
598 Do not use the default directory of trusted certificates.
602 =head2 Random State Options
604 Prior to OpenSSL 3.0, it was common for applications to store information
605 about the state of the random-number generator in a file that was loaded
606 at startup and rewritten upon exit. On modern operating systems, this is
607 generally no longer necessary as OpenSSL will seed itself from the
608 appropriate CPU flags, device files, and so on. These flags are still
609 supported for special platforms or circumstances that might require them.
611 It is generally an error to use the same seed file more than once and
612 every use of B<-rand> should be paired with B<-writerand>.
616 =item B<-rand> I<files>
618 A file or files containing random data used to seed the random number
620 Multiple files can be specified separated by an OS-dependent character.
621 The separator is C<;> for MS-Windows, C<,> for OpenVMS, and C<:> for
622 all others. Another way to specify multiple files is to repeat this flag
623 with different filenames.
625 =item B<-writerand> I<file>
627 Writes the seed data to the specified I<file> upon exit.
628 This file can be used in a subsequent command invocation.
636 =item B<OPENSSL_TRACE=>I<name>[,...]
638 Enable tracing output of OpenSSL library, by name.
639 This output will only make sense if you know OpenSSL internals well.
640 Also, it might not give you any output at all, depending on how
643 The value is a comma separated list of names, with the following
650 The tracing functionality.
662 ENGINE configuration.
664 =item B<ENGINE_TABLE>
666 The function that is used by RSA, DSA (etc) code to select registered
667 ENGINEs, cache defaults and functional references (etc), will generate
670 =item B<ENGINE_REF_COUNT>
672 Reference counts in the ENGINE structure will be monitored with a line
673 of generated for each change.
679 =item B<PKCS12_KEYGEN>
681 PKCS#12 key generation.
683 =item B<PKCS12_DECRYPT>
687 =item B<X509V3_POLICY>
689 Generates the complete policy tree at various point during X.509 v3
702 L<openssl-asn1parse(1)>,
704 L<openssl-ciphers(1)>,
707 L<openssl-crl2pkcs7(1)>,
709 L<openssl-dhparam(1)>,
711 L<openssl-dsaparam(1)>,
713 L<openssl-ecparam(1)>,
715 L<openssl-engine(1)>,
716 L<openssl-errstr(1)>,
717 L<openssl-gendsa(1)>,
718 L<openssl-genpkey(1)>,
719 L<openssl-genrsa(1)>,
724 L<openssl-passwd(1)>,
725 L<openssl-pkcs12(1)>,
729 L<openssl-pkeyparam(1)>,
730 L<openssl-pkeyutl(1)>,
733 L<openssl-rehash(1)>,
736 L<openssl-rsautl(1)>,
737 L<openssl-s_client(1)>,
738 L<openssl-s_server(1)>,
739 L<openssl-s_time(1)>,
740 L<openssl-sess_id(1)>,
745 L<openssl-storeutl(1)>,
747 L<openssl-verify(1)>,
748 L<openssl-version(1)>,
758 The B<list> -I<XXX>B<-algorithms> options were added in OpenSSL 1.0.0;
759 For notes on the availability of other commands, see their individual
764 Copyright 2000-2019 The OpenSSL Project Authors. All Rights Reserved.
766 Licensed under the Apache License 2.0 (the "License"). You may not use
767 this file except in compliance with the License. You can obtain a copy
768 in the file LICENSE in the source distribution or at
769 L<https://www.openssl.org/source/license.html>.