5 openssl-cms - CMS utility
24 [B<-EncryptedData_encrypt>]
26 [B<-verify_receipt> I<receipt>]
28 [B<-inform> B<DER>|B<PEM>|B<SMIME>]
29 [B<-rctform> B<DER>|B<PEM>|B<SMIME>]
31 [B<-outform> B<DER>|B<PEM>|B<SMIME>]
36 [B<-content> I<filename>]
44 [B<-attime> I<timestamp>]
58 [B<-purpose> I<purpose>]
65 [B<-auth_level> I<num>]
66 [B<-verify_depth> I<num>]
67 [B<-verify_email> I<email>]
68 [B<-verify_hostname> I<hostname>]
70 [B<-verify_name> I<name>]
83 [B<-certfile> I<file>]
84 [B<-certsout> I<file>]
88 [B<-receipt_request_all>]
89 [B<-receipt_request_first>]
90 [B<-receipt_request_from> I<emailaddress>]
91 [B<-receipt_request_to> I<emailaddress>]
92 [B<-receipt_request_print>]
93 [B<-secretkey> I<key>]
94 [B<-secretkeyid> I<id>]
95 [B<-econtent_type> I<type>]
97 [B<-keyopt> I<name>:I<parameter>]
100 [B<-writerand> I<file>]
103 [B<-subject> I<subj>]
106 =for comment ifdef des-wrap engine
110 This command handles S/MIME v3.1 mail. It can encrypt, decrypt,
111 sign and verify, compress and uncompress S/MIME messages.
115 There are fourteen operation options that set the type of operation to be
116 performed. The meaning of the other options varies according to the operation
123 Print out a usage message.
127 Encrypt mail for the given recipient certificates. Input file is the message
128 to be encrypted. The output file is the encrypted mail in MIME format. The
129 actual CMS type is <B>EnvelopedData<B>.
131 Note that no revocation check is done for the recipient cert, so if that
132 key has been compromised, others may be able to decrypt the text.
136 Decrypt mail using the supplied certificate and private key. Expects an
137 encrypted mail message in MIME format for the input file. The decrypted mail
138 is written to the output file.
140 =item B<-debug_decrypt>
142 This option sets the B<CMS_DEBUG_DECRYPT> flag. This option should be used
143 with caution: see the notes section below.
147 Sign mail using the supplied certificate and private key. Input file is
148 the message to be signed. The signed message in MIME format is written
153 Verify signed mail. Expects a signed mail message on input and outputs
154 the signed data. Both clear text and opaque signing is supported.
158 Takes an input message and writes out a PEM encoded CMS structure.
162 Resign a message: take an existing message and one or more new signers.
166 Add an ESS signing-certificate or ESS signing-certificate-v2 signed-attribute to the SignerInfo, in order to make
167 the signature comply with the requirements for a CAdES Basic Electronic Signature (CAdES-BES). See the NOTES
168 section for more details.
170 =item B<-data_create>
172 Create a CMS B<Data> type.
176 B<Data> type and output the content.
178 =item B<-digest_create>
180 Create a CMS B<DigestedData> type.
182 =item B<-digest_verify>
184 Verify a CMS B<DigestedData> type and output the content.
188 Create a CMS B<CompressedData> type. OpenSSL must be compiled with B<zlib>
189 support for this option to work, otherwise it will output an error.
193 Uncompress a CMS B<CompressedData> type and output the content. OpenSSL must be
194 compiled with B<zlib> support for this option to work, otherwise it will
197 =item B<-EncryptedData_encrypt>
199 Encrypt content using supplied symmetric key and algorithm using a CMS
200 B<EncryptedData> type and output the content.
202 =item B<-sign_receipt>
204 Generate and output a signed receipt for the supplied message. The input
205 message B<must> contain a signed receipt request. Functionality is otherwise
206 similar to the B<-sign> operation.
208 =item B<-verify_receipt> I<receipt>
210 Verify a signed receipt in filename B<receipt>. The input message B<must>
211 contain the original receipt request. Functionality is otherwise similar
212 to the B<-verify> operation.
214 =item B<-in> I<filename>
216 The input message to be encrypted or signed or the message to be decrypted
219 =item B<-inform> B<DER>|B<PEM>|B<SMIME>
221 This specifies the input format for the CMS structure. The default
222 is B<SMIME> which reads an S/MIME format message. B<PEM> and B<DER>
223 format change this to expect PEM and DER format CMS structures
224 instead. This currently only affects the input format of the CMS
225 structure, if no CMS structure is being input (for example with
226 B<-encrypt> or B<-sign>) this option has no effect.
228 =item B<-rctform> B<DER>|B<PEM>|B<SMIME>
230 Specify the format for a signed receipt for use with the B<-receipt_verify>
233 =item B<-out> I<filename>
235 The message text that has been decrypted or verified or the output MIME
236 format message that has been signed or verified.
238 =item B<-outform> B<DER>|B<PEM>|B<SMIME>
240 This specifies the output format for the CMS structure. The default
241 is B<SMIME> which writes an S/MIME format message. B<PEM> and B<DER>
242 format change this to write PEM and DER format CMS structures
243 instead. This currently only affects the output format of the CMS
244 structure, if no CMS structure is being output (for example with
245 B<-verify> or B<-decrypt>) this option has no effect.
247 =item B<-stream>, B<-indef>, B<-noindef>
249 The B<-stream> and B<-indef> options are equivalent and enable streaming I/O
250 for encoding operations. This permits single pass processing of data without
251 the need to hold the entire contents in memory, potentially supporting very
252 large files. Streaming is automatically set for S/MIME signing with detached
253 data if the output format is B<SMIME> it is currently off by default for all
258 Disable streaming I/O where it would produce and indefinite length constructed
259 encoding. This option currently has no effect. In future streaming will be
260 enabled by default on all relevant operations and this option will disable it.
262 =item B<-content> I<filename>
264 This specifies a file containing the detached content, this is only
265 useful with the B<-verify> command. This is only usable if the CMS
266 structure is using the detached signature form where the content is
267 not included. This option will override any content if the input format
268 is S/MIME and it uses the multipart/signed MIME content type.
272 This option adds plain text (text/plain) MIME headers to the supplied
273 message if encrypting or signing. If decrypting or verifying it strips
274 off text headers: if the decrypted or verified message is not of MIME
275 type text/plain then an error occurs.
279 For the B<-cmsout> operation do not output the parsed CMS structure. This
280 is useful when combined with the B<-print> option or if the syntax of the CMS
281 structure is being checked.
285 For the B<-cmsout> operation print out all fields of the CMS structure. This
286 is mainly useful for testing purposes.
288 =item B<-CAfile> I<file>
290 A file containing trusted CA certificates, only used with B<-verify>.
292 =item B<-CApath> I<dir>
294 A directory containing trusted CA certificates, only used with
295 B<-verify>. This directory must be a standard certificate directory: that
296 is a hash of each subject name (using C<x509 -hash>) should be linked
301 Do not load the trusted CA certificates from the default file location
305 Do not load the trusted CA certificates from the default directory location
307 =item B<-md> I<digest>
309 Digest algorithm to use when signing or resigning. If not present then the
310 default digest algorithm for the signing key will be used (usually SHA1).
314 The encryption algorithm to use. For example triple DES (168 bits) - B<-des3>
315 or 256 bit AES - B<-aes256>. Any standard algorithm name (as used by the
316 EVP_get_cipherbyname() function) can also be used preceded by a dash, for
317 example B<-aes-128-cbc>. See L<openssl-enc(1)> for a list of ciphers
318 supported by your version of OpenSSL.
320 If not specified triple DES is used. Only used with B<-encrypt> and
321 B<-EncryptedData_create> commands.
325 When verifying a message normally certificates (if any) included in
326 the message are searched for the signing certificate. With this option
327 only the certificates specified in the B<-certfile> option are used.
328 The supplied certificates can still be used as untrusted CAs however.
332 Do not verify the signers certificate of a signed message.
336 When signing a message the signer's certificate is normally included
337 with this option it is excluded. This will reduce the size of the
338 signed message but the verifier must have a copy of the signers certificate
339 available locally (passed using the B<-certfile> option for example).
343 Normally when a message is signed a set of attributes are included which
344 include the signing time and supported symmetric algorithms. With this
345 option they are not included.
349 Exclude the list of supported algorithms from signed attributes, other options
350 such as signing time and content type are still included.
354 Normally the input message is converted to "canonical" format which is
355 effectively using CR and LF as end of line: as required by the S/MIME
356 specification. When this option is present no translation occurs. This
357 is useful when handling binary data which may not be in MIME format.
361 Normally the output file uses a single B<LF> as end of line. When this
362 option is present B<CRLF> is used instead.
366 When signing use ASCII CRLF format canonicalisation. This strips trailing
367 whitespace from all lines, deletes trailing blank lines at EOF and sets
368 the encapsulated content type. This option is normally used with detached
369 content and an output signature format of DER. This option is not normally
370 needed when verifying as it is enabled automatically if the encapsulated
371 content format is detected.
375 When signing a message use opaque signing: this form is more resistant
376 to translation by mail relays but it cannot be read by mail agents that
377 do not support S/MIME. Without this option cleartext signing with
378 the MIME type multipart/signed is used.
380 =item B<-certfile> I<file>
382 Allows additional certificates to be specified. When signing these will
383 be included with the message. When verifying these will be searched for
384 the signers certificates. The certificates should be in PEM format.
386 =item B<-certsout> I<file>
388 Any certificates contained in the message are written to I<file>.
390 =item B<-signer> I<file>
392 A signing certificate when signing or resigning a message, this option can be
393 used multiple times if more than one signer is required. If a message is being
394 verified then the signers certificates will be written to this file if the
395 verification was successful.
397 =item B<-recip> I<file>
399 When decrypting a message this specifies the recipients certificate. The
400 certificate must match one of the recipients of the message or an error
403 When encrypting a message this option may be used multiple times to specify
404 each recipient. This form B<must> be used if customised parameters are
405 required (for example to specify RSA-OAEP).
407 Only certificates carrying RSA, Diffie-Hellman or EC keys are supported by this
412 Use subject key identifier to identify certificates instead of issuer name and
413 serial number. The supplied certificate B<must> include a subject key
414 identifier extension. Supported by B<-sign> and B<-encrypt> options.
416 =item B<-receipt_request_all>, B<-receipt_request_first>
418 For B<-sign> option include a signed receipt request. Indicate requests should
419 be provided by all recipient or first tier recipients (those mailed directly
420 and not from a mailing list). Ignored it B<-receipt_request_from> is included.
422 =item B<-receipt_request_from> I<emailaddress>
424 For B<-sign> option include a signed receipt request. Add an explicit email
425 address where receipts should be supplied.
427 =item B<-receipt_request_to> I<emailaddress>
429 Add an explicit email address where signed receipts should be sent to. This
430 option B<must> but supplied if a signed receipt it requested.
432 =item B<-receipt_request_print>
434 For the B<-verify> operation print out the contents of any signed receipt
437 =item B<-secretkey> I<key>
439 Specify symmetric key to use. The key must be supplied in hex format and be
440 consistent with the algorithm used. Supported by the B<-EncryptedData_encrypt>
441 B<-EncryptedData_decrypt>, B<-encrypt> and B<-decrypt> options. When used
442 with B<-encrypt> or B<-decrypt> the supplied key is used to wrap or unwrap the
443 content encryption key using an AES key in the B<KEKRecipientInfo> type.
445 =item B<-secretkeyid> I<id>
447 The key identifier for the supplied symmetric key for B<KEKRecipientInfo> type.
448 This option B<must> be present if the B<-secretkey> option is used with
449 B<-encrypt>. With B<-decrypt> operations the I<id> is used to locate the
450 relevant key if it is not supplied then an attempt is used to decrypt any
451 B<KEKRecipientInfo> structures.
453 =item B<-econtent_type> I<type>
455 Set the encapsulated content type to I<type> if not supplied the B<Data> type
456 is used. The I<type> argument can be any valid OID name in either text or
459 =item B<-inkey> I<file>
461 The private key to use when signing or decrypting. This must match the
462 corresponding certificate. If this option is not specified then the
463 private key must be included in the certificate file specified with
464 the B<-recip> or B<-signer> file. When signing this option can be used
465 multiple times to specify successive keys.
467 =item B<-keyopt> I<name>:I<parameter>
469 For signing and encryption this option can be used multiple times to
470 set customised parameters for the preceding key or certificate. It can
471 currently be used to set RSA-PSS for signing, RSA-OAEP for encryption
472 or to modify default parameters for ECDH.
474 =item B<-passin> I<arg>
476 The private key password source. For more information about the format of B<arg>
477 see L<openssl(1)/Pass phrase options>.
479 =item B<-rand> I<files>
481 The files containing random data used to seed the random number generator.
482 Multiple files can be specified separated by an OS-dependent character.
483 The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for
486 =item B<-writerand> I<file>
488 Writes random data to the specified I<file> upon exit.
489 This can be used with a subsequent B<-rand> flag.
491 =item I<cert.pem> ...
493 One or more certificates of message recipients: used when encrypting
496 =item B<-to>, B<-from>, B<-subject>
498 The relevant mail headers. These are included outside the signed
499 portion of a message so they may be included manually. If signing
500 then many S/MIME mail clients check the signers certificate's email
501 address matches that specified in the From: address.
503 =item B<-attime>, B<-check_ss_sig>, B<-crl_check>, B<-crl_check_all>,
504 B<-explicit_policy>, B<-extended_crl>, B<-ignore_critical>, B<-inhibit_any>,
505 B<-inhibit_map>, B<-no_alt_chains>, B<-no_check_time>, B<-partial_chain>, B<-policy>,
506 B<-policy_check>, B<-policy_print>, B<-purpose>, B<-suiteB_128>,
507 B<-suiteB_128_only>, B<-suiteB_192>, B<-trusted_first>, B<-use_deltas>,
508 B<-auth_level>, B<-verify_depth>, B<-verify_email>, B<-verify_hostname>,
509 B<-verify_ip>, B<-verify_name>, B<-x509_strict>
511 Set various certificate chain validation options. See the
512 L<openssl-verify(1)> manual page for details.
518 The MIME message must be sent without any blank lines between the
519 headers and the output. Some mail programs will automatically add
520 a blank line. Piping the mail directly to sendmail is one way to
521 achieve the correct format.
523 The supplied message to be signed or encrypted must include the
524 necessary MIME headers or many S/MIME clients won't display it
525 properly (if at all). You can use the B<-text> option to automatically
526 add plain text headers.
528 A "signed and encrypted" message is one where a signed message is
529 then encrypted. This can be produced by encrypting an already signed
530 message: see the examples section.
532 This version of the program only allows one signer per message but it
533 will verify multiple signers on received messages. Some S/MIME clients
534 choke if a message contains multiple signers. It is possible to sign
535 messages "in parallel" by signing an already signed message.
537 The options B<-encrypt> and B<-decrypt> reflect common usage in S/MIME
538 clients. Strictly speaking these process CMS enveloped data: CMS
539 encrypted data is used for other purposes.
541 The B<-resign> option uses an existing message digest when adding a new
542 signer. This means that attributes must be present in at least one existing
543 signer using the same message digest or this operation will fail.
545 The B<-stream> and B<-indef> options enable streaming I/O support.
546 As a result the encoding is BER using indefinite length constructed encoding
547 and no longer DER. Streaming is supported for the B<-encrypt> operation and the
548 B<-sign> operation if the content is not detached.
550 Streaming is always used for the B<-sign> operation with detached data but
551 since the content is no longer part of the CMS structure the encoding
554 If the B<-decrypt> option is used without a recipient certificate then an
555 attempt is made to locate the recipient by trying each potential recipient
556 in turn using the supplied private key. To thwart the MMA attack
557 (Bleichenbacher's attack on PKCS #1 v1.5 RSA padding) all recipients are
558 tried whether they succeed or not and if no recipients match the message
559 is "decrypted" using a random key which will typically output garbage.
560 The B<-debug_decrypt> option can be used to disable the MMA attack protection
561 and return an error if no recipient can be found: this option should be used
562 with caution. For a fuller description see L<CMS_decrypt(3)>).
564 =head1 CADES BASIC ELECTRONIC SIGNATURE (CADES-BES)
566 A CAdES Basic Electronic Signature (CAdES-BES), as defined in the European Standard ETSI EN 319 122-1 V1.1.1, contains:
572 The signed user data as defined in CMS (RFC 3852);
576 Content-type of the EncapsulatedContentInfo value being signed;
580 Message-digest of the eContent OCTET STRING within encapContentInfo being signed;
584 An ESS signing-certificate or ESS signing-certificate-v2 attribute, as defined in Enhanced Security Services (ESS), RFC 2634 and RFC 5035.
585 An ESS signing-certificate attribute only allows for the use of SHA-1 as a digest algorithm.
586 An ESS signing-certificate-v2 attribute allows for the use of any digest algorithm.
590 The digital signature value computed on the user data and, when present, on the signed attributes.
592 Note that currently the B<-cades> option applies only to the B<-sign> operation and is ignored during
593 the B<-verify> operation, i.e. the signing certification is not checked during the verification process.
594 This feature might be added in a future version.
604 The operation was completely successfully.
608 An error occurred parsing the command options.
612 One of the input files could not be read.
616 An error occurred creating the CMS file or when reading the MIME
621 An error occurred decrypting or verifying the message.
625 The message was verified correctly but an error occurred writing out
626 the signers certificates.
630 =head1 COMPATIBILITY WITH PKCS#7 FORMAT
632 L<openssl-smime(1)> can only process the older B<PKCS#7> format.
633 B<openssl cms> supports Cryptographic Message Syntax format.
634 Use of some features will result in messages which cannot be processed by
635 applications which only support the older format. These are detailed below.
637 The use of the B<-keyid> option with B<-sign> or B<-encrypt>.
639 The B<-outform> I<PEM> option uses different headers.
641 The B<-compress> option.
643 The B<-secretkey> option when used with B<-encrypt>.
645 The use of PSS with B<-sign>.
647 The use of OAEP or non-RSA keys with B<-encrypt>.
649 Additionally the B<-EncryptedData_create> and B<-data_create> type cannot
650 be processed by the older L<openssl-smime(1)> command.
654 Create a cleartext signed message:
656 openssl cms -sign -in message.txt -text -out mail.msg \
659 Create an opaque signed message
661 openssl cms -sign -in message.txt -text -out mail.msg -nodetach \
664 Create a signed message, include some additional certificates and
665 read the private key from another file:
667 openssl cms -sign -in in.txt -text -out mail.msg \
668 -signer mycert.pem -inkey mykey.pem -certfile mycerts.pem
670 Create a signed message with two signers, use key identifier:
672 openssl cms -sign -in message.txt -text -out mail.msg \
673 -signer mycert.pem -signer othercert.pem -keyid
675 Send a signed message under Unix directly to sendmail, including headers:
677 openssl cms -sign -in in.txt -text -signer mycert.pem \
678 -from steve@openssl.org -to someone@somewhere \
679 -subject "Signed message" | sendmail someone@somewhere
681 Verify a message and extract the signer's certificate if successful:
683 openssl cms -verify -in mail.msg -signer user.pem -out signedtext.txt
685 Send encrypted mail using triple DES:
687 openssl cms -encrypt -in in.txt -from steve@openssl.org \
688 -to someone@somewhere -subject "Encrypted message" \
689 -des3 user.pem -out mail.msg
691 Sign and encrypt mail:
693 openssl cms -sign -in ml.txt -signer my.pem -text \
694 | openssl cms -encrypt -out mail.msg \
695 -from steve@openssl.org -to someone@somewhere \
696 -subject "Signed and Encrypted message" -des3 user.pem
698 Note: the encryption command does not include the B<-text> option because the
699 message being encrypted already has MIME headers.
703 openssl cms -decrypt -in mail.msg -recip mycert.pem -inkey key.pem
705 The output from Netscape form signing is a PKCS#7 structure with the
706 detached signature format. You can use this program to verify the
707 signature by line wrapping the base64 encoded structure and surrounding
710 -----BEGIN PKCS7-----
713 and using the command,
715 openssl cms -verify -inform PEM -in signature.pem -content content.txt
717 alternatively you can base64 decode the signature and use
719 openssl cms -verify -inform DER -in signature.der -content content.txt
721 Create an encrypted message using 128 bit Camellia:
723 openssl cms -encrypt -in plain.txt -camellia128 -out mail.msg cert.pem
725 Add a signer to an existing message:
727 openssl cms -resign -in mail.msg -signer newsign.pem -out mail2.msg
729 Sign mail using RSA-PSS:
731 openssl cms -sign -in message.txt -text -out mail.msg \
732 -signer mycert.pem -keyopt rsa_padding_mode:pss
734 Create encrypted mail using RSA-OAEP:
736 openssl cms -encrypt -in plain.txt -out mail.msg \
737 -recip cert.pem -keyopt rsa_padding_mode:oaep
739 Use SHA256 KDF with an ECDH certificate:
741 openssl cms -encrypt -in plain.txt -out mail.msg \
742 -recip ecdhcert.pem -keyopt ecdh_kdf_md:sha256
746 The MIME parser isn't very clever: it seems to handle most messages that I've
747 thrown at it but it may choke on others.
749 The code currently will only write out the signer's certificate to a file: if
750 the signer has a separate encryption certificate this must be manually
751 extracted. There should be some heuristic that determines the correct
752 encryption certificate.
754 Ideally a database should be maintained of a certificates for each email
757 The code doesn't currently take note of the permitted symmetric encryption
758 algorithms as supplied in the SMIMECapabilities signed attribute. this means the
759 user has to manually include the correct encryption algorithm. It should store
760 the list of permitted ciphers in a database and only use those.
762 No revocation checking is done on the signer's certificate.
766 The use of multiple B<-signer> options and the B<-resign> command were first
767 added in OpenSSL 1.0.0.
769 The B<-keyopt> option was added in OpenSSL 1.0.2.
771 Support for RSA-OAEP and RSA-PSS was added in OpenSSL 1.0.2.
773 The use of non-RSA keys with B<-encrypt> and B<-decrypt>
774 was added in OpenSSL 1.0.2.
776 The -no_alt_chains option was added in OpenSSL 1.0.2b.
780 Copyright 2008-2019 The OpenSSL Project Authors. All Rights Reserved.
782 Licensed under the Apache License 2.0 (the "License"). You may not use
783 this file except in compliance with the License. You can obtain a copy
784 in the file LICENSE in the source distribution or at
785 L<https://www.openssl.org/source/license.html>.