2 {- OpenSSL::safe::output_do_not_edit_headers(); -}
6 openssl-cms - CMS command
17 {- $OpenSSL::safe::opt_config_synopsis -}
27 [B<-verify_receipt> I<receipt>]
32 [B<-EncryptedData_encrypt>]
33 [B<-EncryptedData_decrypt>]
40 [B<-inform> B<DER>|B<PEM>|B<SMIME>]
41 [B<-outform> B<DER>|B<PEM>|B<SMIME>]
42 [B<-rctform> B<DER>|B<PEM>|B<SMIME>]
50 Keys and password options:
52 [B<-pwri_password> I<password>]
53 [B<-secretkey> I<key>]
54 [B<-secretkeyid> I<id>]
55 [B<-inkey> I<filename>|I<uri>]
57 [B<-keyopt> I<name>:I<parameter>]
58 [B<-keyform> B<DER>|B<PEM>|B<P12>|B<ENGINE>]
59 {- $OpenSSL::safe::opt_engine_synopsis -}{- $OpenSSL::safe::opt_provider_synopsis -}
60 {- $OpenSSL::safe::opt_r_synopsis -}
64 [B<-originator> I<file>]
66 [I<recipient-cert> ...]
79 [B<-certfile> I<file>]
85 [B<-receipt_request_all>]
86 [B<-receipt_request_first>]
87 [B<-receipt_request_from> I<emailaddress>]
88 [B<-receipt_request_to> I<emailaddress>]
93 [B<-content> I<filename>]
94 [B<-no_content_verify>]
101 {- $OpenSSL::safe::opt_trust_synopsis -}
106 [B<-econtent_type> I<type>]
108 [B<-certsout> I<file>]
111 [B<-subject> I<subj>]
117 [B<-nameopt> I<option>]
118 [B<-receipt_request_print>]
122 {- $OpenSSL::safe::opt_v_synopsis -}
126 This command handles data in CMS format such as S/MIME v3.1 email messages.
127 It can encrypt, decrypt, sign, verify, compress, uncompress, and print messages.
131 There are a number of operation options that set the type of operation to be
132 performed: encrypt, decrypt, sign, verify, resign, sign_receipt, verify_receipt,
133 digest_create, digest_verify, compress, uncompress,
134 EncryptedData_encrypt, EncryptedData_decrypt, data_create, data_out, or cmsout.
135 The relevance of the other options depends on the operation type
136 and their meaning may vary according to it.
142 Print out a usage message.
146 =head2 General options
150 =item B<-in> I<filename>
152 The input message to be encrypted or signed or the message to be decrypted
155 =item B<-out> I<filename>
157 The message text that has been decrypted or verified or the output MIME
158 format message that has been signed or verified.
160 {- $OpenSSL::safe::opt_config_item -}
164 =head2 Operation options
170 Encrypt data for the given recipient certificates. Input file is the message
171 to be encrypted. The output file is the encrypted data in MIME format. The
172 actual CMS type is B<EnvelopedData>.
174 Note that no revocation check is done for the recipient cert, so if that
175 key has been compromised, others may be able to decrypt the text.
179 Decrypt data using the supplied certificate and private key. Expects
180 encrypted datain MIME format for the input file. The decrypted data
181 is written to the output file.
185 Sign data using the supplied certificate and private key. Input file is
186 the message to be signed. The signed data in MIME format is written
191 Verify signed data. Expects a signed data on input and outputs
192 the signed data. Both clear text and opaque signing is supported.
196 Resign a message: take an existing message and one or more new signers.
198 =item B<-sign_receipt>
200 Generate and output a signed receipt for the supplied message. The input
201 message B<must> contain a signed receipt request. Functionality is otherwise
202 similar to the B<-sign> operation.
204 =item B<-verify_receipt> I<receipt>
206 Verify a signed receipt in filename B<receipt>. The input message B<must>
207 contain the original receipt request. Functionality is otherwise similar
208 to the B<-verify> operation.
210 =item B<-digest_create>
212 Create a CMS B<DigestedData> type.
214 =item B<-digest_verify>
216 Verify a CMS B<DigestedData> type and output the content.
220 Create a CMS B<CompressedData> type. OpenSSL must be compiled with B<zlib>
221 support for this option to work, otherwise it will output an error.
225 Uncompress a CMS B<CompressedData> type and output the content. OpenSSL must be
226 compiled with B<zlib> support for this option to work, otherwise it will
229 =item B<-EncryptedData_encrypt>
231 Encrypt content using supplied symmetric key and algorithm using a CMS
232 B<EncryptedData> type and output the content.
234 =item B<-EncryptedData_decrypt>
236 Decrypt content using supplied symmetric key and algorithm using a CMS
237 B<EncryptedData> type and output the content.
239 =item B<-data_create>
241 Create a CMS B<Data> type.
245 B<Data> type and output the content.
249 Takes an input message and writes out a PEM encoded CMS structure.
253 =head2 File format options
257 =item B<-inform> B<DER>|B<PEM>|B<SMIME>
259 The input format of the CMS structure (if one is being read);
260 the default is B<SMIME>.
261 See L<openssl-format-options(1)> for details.
263 =item B<-outform> B<DER>|B<PEM>|B<SMIME>
265 The output format of the CMS structure (if one is being written);
266 the default is B<SMIME>.
267 See L<openssl-format-options(1)> for details.
269 =item B<-rctform> B<DER>|B<PEM>|B<SMIME>
271 The signed receipt format for use with the B<-receipt_verify>; the default
273 See L<openssl-format-options(1)> for details.
275 =item B<-stream>, B<-indef>
277 The B<-stream> and B<-indef> options are equivalent and enable streaming I/O
278 for encoding operations. This permits single pass processing of data without
279 the need to hold the entire contents in memory, potentially supporting very
280 large files. Streaming is automatically set for S/MIME signing with detached
281 data if the output format is B<SMIME> it is currently off by default for all
286 Disable streaming I/O where it would produce and indefinite length constructed
287 encoding. This option currently has no effect. In future streaming will be
288 enabled by default on all relevant operations and this option will disable it.
292 Normally the input message is converted to "canonical" format which is
293 effectively using CR and LF as end of line: as required by the S/MIME
294 specification. When this option is present no translation occurs. This
295 is useful when handling binary data which may not be in MIME format.
299 Normally the output file uses a single B<LF> as end of line. When this
300 option is present B<CRLF> is used instead.
304 When signing use ASCII CRLF format canonicalisation. This strips trailing
305 whitespace from all lines, deletes trailing blank lines at EOF and sets
306 the encapsulated content type. This option is normally used with detached
307 content and an output signature format of DER. This option is not normally
308 needed when verifying as it is enabled automatically if the encapsulated
309 content format is detected.
313 =head2 Keys and password options
317 =item B<-pwri_password> I<password>
319 Specify password for recipient.
321 =item B<-secretkey> I<key>
323 Specify symmetric key to use. The key must be supplied in hex format and be
324 consistent with the algorithm used. Supported by the B<-EncryptedData_encrypt>
325 B<-EncryptedData_decrypt>, B<-encrypt> and B<-decrypt> options. When used
326 with B<-encrypt> or B<-decrypt> the supplied key is used to wrap or unwrap the
327 content encryption key using an AES key in the B<KEKRecipientInfo> type.
329 =item B<-secretkeyid> I<id>
331 The key identifier for the supplied symmetric key for B<KEKRecipientInfo> type.
332 This option B<must> be present if the B<-secretkey> option is used with
333 B<-encrypt>. With B<-decrypt> operations the I<id> is used to locate the
334 relevant key if it is not supplied then an attempt is used to decrypt any
335 B<KEKRecipientInfo> structures.
337 =item B<-inkey> I<filename>|I<uri>
339 The private key to use when signing or decrypting. This must match the
340 corresponding certificate. If this option is not specified then the
341 private key must be included in the certificate file specified with
342 the B<-recip> or B<-signer> file. When signing this option can be used
343 multiple times to specify successive keys.
345 =item B<-passin> I<arg>
347 The private key password source. For more information about the format of B<arg>
348 see L<openssl-passphrase-options(1)>.
350 =item B<-keyopt> I<name>:I<parameter>
352 For signing and encryption this option can be used multiple times to
353 set customised parameters for the preceding key or certificate. It can
354 currently be used to set RSA-PSS for signing, RSA-OAEP for encryption
355 or to modify default parameters for ECDH.
357 =item B<-keyform> B<DER>|B<PEM>|B<P12>|B<ENGINE>
359 The format of the private key file; unspecified by default.
360 See L<openssl-format-options(1)> for details.
362 {- $OpenSSL::safe::opt_engine_item -}
364 {- $OpenSSL::safe::opt_provider_item -}
366 {- $OpenSSL::safe::opt_r_item -}
370 =head2 Encryption and decryption options
374 =item B<-originator> I<file>
376 A certificate of the originator of the encrypted message. Necessary for
377 decryption when Key Agreement is in use for a shared key.
379 =item B<-recip> I<file>
381 When decrypting a message this specifies the certificate of the recipient.
382 The certificate must match one of the recipients of the message.
384 When encrypting a message this option may be used multiple times to specify
385 each recipient. This form B<must> be used if customised parameters are
386 required (for example to specify RSA-OAEP).
388 Only certificates carrying RSA, Diffie-Hellman or EC keys are supported by this
391 =item I<recipient-cert> ...
393 This is an alternative to using the B<-recip> option when encrypting a message.
394 One or more certificate filennames may be given.
398 The encryption algorithm to use. For example triple DES (168 bits) - B<-des3>
399 or 256 bit AES - B<-aes256>. Any standard algorithm name (as used by the
400 EVP_get_cipherbyname() function) can also be used preceded by a dash, for
401 example B<-aes-128-cbc>. See L<openssl-enc(1)> for a list of ciphers
402 supported by your version of OpenSSL.
404 Currently the AES variants with GCM mode are the only supported AEAD
407 If not specified triple DES is used. Only used with B<-encrypt> and
408 B<-EncryptedData_create> commands.
410 =item B<-wrap> I<cipher>
412 Cipher algorithm to use for key wrap when encrypting the message using Key
413 Agreement for key transport. The algorithm specified should be suitable for key
416 =item B<-aes128-wrap>, B<-aes192-wrap>, B<-aes256-wrap>, B<-des3-wrap>
418 Use AES128, AES192, AES256, or 3DES-EDE, respectively, to wrap key.
419 Depending on the OpenSSL build options used, B<-des3-wrap> may not be supported.
421 =item B<-debug_decrypt>
423 This option sets the B<CMS_DEBUG_DECRYPT> flag. This option should be used
424 with caution: see the notes section below.
428 =head2 Signing options
432 =item B<-md> I<digest>
434 Digest algorithm to use when signing or resigning. If not present then the
435 default digest algorithm for the signing key will be used (usually SHA1).
437 =item B<-signer> I<file>
439 A signing certificate. When signing or resigning a message, this option can be
440 used multiple times if more than one signer is required.
442 =item B<-certfile> I<file>
444 Allows additional certificates to be specified. When signing these will
445 be included with the message. When verifying these will be searched for
446 the signers certificates.
447 The input can be in PEM, DER, or PKCS#12 format.
451 When used with B<-sign>,
452 add an ESS signingCertificate or ESS signingCertificateV2 signed-attribute
453 to the SignerInfo, in order to make the signature comply with the requirements
454 for a CAdES Basic Electronic Signature (CAdES-BES).
458 When signing a message use opaque signing: this form is more resistant
459 to translation by mail relays but it cannot be read by mail agents that
460 do not support S/MIME. Without this option cleartext signing with
461 the MIME type multipart/signed is used.
465 When signing a message the signer's certificate is normally included
466 with this option it is excluded. This will reduce the size of the
467 signed message but the verifier must have a copy of the signers certificate
468 available locally (passed using the B<-certfile> option for example).
472 Normally when a message is signed a set of attributes are included which
473 include the signing time and supported symmetric algorithms. With this
474 option they are not included.
478 Exclude the list of supported algorithms from signed attributes, other options
479 such as signing time and content type are still included.
481 =item B<-receipt_request_all>, B<-receipt_request_first>
483 For B<-sign> option include a signed receipt request. Indicate requests should
484 be provided by all recipient or first tier recipients (those mailed directly
485 and not from a mailing list). Ignored it B<-receipt_request_from> is included.
487 =item B<-receipt_request_from> I<emailaddress>
489 For B<-sign> option include a signed receipt request. Add an explicit email
490 address where receipts should be supplied.
492 =item B<-receipt_request_to> I<emailaddress>
494 Add an explicit email address where signed receipts should be sent to. This
495 option B<must> but supplied if a signed receipt is requested.
499 =head2 Verification options
503 =item B<-signer> I<file>
505 If a message has been verified successfully then the signers certificate(s)
506 will be written to this file if the verification was successful.
508 =item B<-content> I<filename>
510 This specifies a file containing the detached content for operations taking
511 S/MIME input, such as the B<-verify> command. This is only usable if the CMS
512 structure is using the detached signature form where the content is
513 not included. This option will override any content if the input format
514 is S/MIME and it uses the multipart/signed MIME content type.
516 =item B<-no_content_verify>
518 Do not verify signed content signatures.
520 =item B<-no_attr_verify>
522 Do not verify signed attribute signatures.
526 Don't verify message signature.
530 Do not verify the signers certificate of a signed message.
534 When verifying a message normally certificates (if any) included in
535 the message are searched for the signing certificate. With this option
536 only the certificates specified in the B<-certfile> option are used.
537 The supplied certificates can still be used as untrusted CAs however.
541 When used with B<-verify>, require and check signer certificate digest.
542 See the NOTES section for more details.
544 =item B<-verify_retcode>
546 Exit nonzero on verification failure.
548 {- $OpenSSL::safe::opt_trust_item -}
552 =head2 Output options
558 Use subject key identifier to identify certificates instead of issuer name and
559 serial number. The supplied certificate B<must> include a subject key
560 identifier extension. Supported by B<-sign> and B<-encrypt> options.
562 =item B<-econtent_type> I<type>
564 Set the encapsulated content type to I<type> if not supplied the B<Data> type
565 is used. The I<type> argument can be any valid OID name in either text or
570 This option adds plain text (text/plain) MIME headers to the supplied
571 message if encrypting or signing. If decrypting or verifying it strips
572 off text headers: if the decrypted or verified message is not of MIME
573 type text/plain then an error occurs.
575 =item B<-certsout> I<file>
577 Any certificates contained in the input message are written to I<file>.
579 =item B<-to>, B<-from>, B<-subject>
581 The relevant email headers. These are included outside the signed
582 portion of a message so they may be included manually. If signing
583 then many S/MIME mail clients check the signers certificate's email
584 address matches that specified in the From: address.
588 =head2 Printing options
594 For the B<-cmsout> operation do not output the parsed CMS structure.
595 This is useful if the syntax of the CMS structure is being checked.
599 For the B<-cmsout> operation print out all fields of the CMS structure.
600 This implies B<-noout>.
601 This is mainly useful for testing purposes.
603 =item B<-nameopt> I<option>
605 For the B<-cmsout> operation when B<-print> option is in use, specifies
606 printing options for string fields. For most cases B<utf8> is reasonable value.
607 See L<openssl-namedisplay-options(1)> for details.
609 =item B<-receipt_request_print>
611 For the B<-verify> operation print out the contents of any signed receipt
616 =head2 Validation options
620 {- $OpenSSL::safe::opt_v_item -}
622 Any validation errors cause the command to exit.
628 The MIME message must be sent without any blank lines between the
629 headers and the output. Some mail programs will automatically add
630 a blank line. Piping the mail directly to sendmail is one way to
631 achieve the correct format.
633 The supplied message to be signed or encrypted must include the
634 necessary MIME headers or many S/MIME clients won't display it
635 properly (if at all). You can use the B<-text> option to automatically
636 add plain text headers.
638 A "signed and encrypted" message is one where a signed message is
639 then encrypted. This can be produced by encrypting an already signed
640 message: see the examples section.
642 This version of the program only allows one signer per message but it
643 will verify multiple signers on received messages. Some S/MIME clients
644 choke if a message contains multiple signers. It is possible to sign
645 messages "in parallel" by signing an already signed message.
647 The options B<-encrypt> and B<-decrypt> reflect common usage in S/MIME
648 clients. Strictly speaking these process CMS enveloped data: CMS
649 encrypted data is used for other purposes.
651 The B<-resign> option uses an existing message digest when adding a new
652 signer. This means that attributes must be present in at least one existing
653 signer using the same message digest or this operation will fail.
655 The B<-stream> and B<-indef> options enable streaming I/O support.
656 As a result the encoding is BER using indefinite length constructed encoding
657 and no longer DER. Streaming is supported for the B<-encrypt> operation and the
658 B<-sign> operation if the content is not detached.
660 Streaming is always used for the B<-sign> operation with detached data but
661 since the content is no longer part of the CMS structure the encoding
664 If the B<-decrypt> option is used without a recipient certificate then an
665 attempt is made to locate the recipient by trying each potential recipient
666 in turn using the supplied private key. To thwart the MMA attack
667 (Bleichenbacher's attack on PKCS #1 v1.5 RSA padding) all recipients are
668 tried whether they succeed or not and if no recipients match the message
669 is "decrypted" using a random key which will typically output garbage.
670 The B<-debug_decrypt> option can be used to disable the MMA attack protection
671 and return an error if no recipient can be found: this option should be used
672 with caution. For a fuller description see L<CMS_decrypt(3)>).
674 =head1 CADES BASIC ELECTRONIC SIGNATURE (CADES-BES)
676 A CAdES Basic Electronic Signature (CAdES-BES),
677 as defined in the European Standard ETSI EN 319 122-1 V1.1.1, contains:
683 The signed user data as defined in CMS (RFC 3852);
687 Content-type of the EncapsulatedContentInfo value being signed;
691 Message-digest of the eContent OCTET STRING within encapContentInfo being signed;
695 An ESS signingCertificate or ESS signingCertificateV2 attribute,
696 as defined in Enhanced Security Services (ESS), RFC 2634 and RFC 5035.
697 An ESS signingCertificate attribute only allows for SHA-1 as digest algorithm.
698 An ESS signingCertificateV2 attribute allows for any digest algorithm.
702 The digital signature value computed on the user data and, when present, on the signed attributes.
704 NOTE that the B<-cades> option applies to the B<-sign> or B<-verify> operations.
705 With this option, the B<-verify> operation also requires that the
706 signingCertificate attribute is present and checks that the given identifiers
707 match the verification trust chain built during the verification process.
717 The operation was completely successfully.
721 An error occurred parsing the command options.
725 One of the input files could not be read.
729 An error occurred creating the CMS file or when reading the MIME
734 An error occurred decrypting or verifying the message.
738 The message was verified correctly but an error occurred writing out
739 the signers certificates.
743 =head1 COMPATIBILITY WITH PKCS#7 FORMAT
745 L<openssl-smime(1)> can only process the older B<PKCS#7> format.
746 B<openssl cms> supports Cryptographic Message Syntax format.
747 Use of some features will result in messages which cannot be processed by
748 applications which only support the older format. These are detailed below.
750 The use of the B<-keyid> option with B<-sign> or B<-encrypt>.
752 The B<-outform> I<PEM> option uses different headers.
754 The B<-compress> option.
756 The B<-secretkey> option when used with B<-encrypt>.
758 The use of PSS with B<-sign>.
760 The use of OAEP or non-RSA keys with B<-encrypt>.
762 Additionally the B<-EncryptedData_create> and B<-data_create> type cannot
763 be processed by the older L<openssl-smime(1)> command.
767 Create a cleartext signed message:
769 openssl cms -sign -in message.txt -text -out mail.msg \
772 Create an opaque signed message
774 openssl cms -sign -in message.txt -text -out mail.msg -nodetach \
777 Create a signed message, include some additional certificates and
778 read the private key from another file:
780 openssl cms -sign -in in.txt -text -out mail.msg \
781 -signer mycert.pem -inkey mykey.pem -certfile mycerts.pem
783 Create a signed message with two signers, use key identifier:
785 openssl cms -sign -in message.txt -text -out mail.msg \
786 -signer mycert.pem -signer othercert.pem -keyid
788 Send a signed message under Unix directly to sendmail, including headers:
790 openssl cms -sign -in in.txt -text -signer mycert.pem \
791 -from steve@openssl.org -to someone@somewhere \
792 -subject "Signed message" | sendmail someone@somewhere
794 Verify a message and extract the signer's certificate if successful:
796 openssl cms -verify -in mail.msg -signer user.pem -out signedtext.txt
798 Send encrypted mail using triple DES:
800 openssl cms -encrypt -in in.txt -from steve@openssl.org \
801 -to someone@somewhere -subject "Encrypted message" \
802 -des3 user.pem -out mail.msg
804 Sign and encrypt mail:
806 openssl cms -sign -in ml.txt -signer my.pem -text \
807 | openssl cms -encrypt -out mail.msg \
808 -from steve@openssl.org -to someone@somewhere \
809 -subject "Signed and Encrypted message" -des3 user.pem
811 Note: the encryption command does not include the B<-text> option because the
812 message being encrypted already has MIME headers.
816 openssl cms -decrypt -in mail.msg -recip mycert.pem -inkey key.pem
818 The output from Netscape form signing is a PKCS#7 structure with the
819 detached signature format. You can use this program to verify the
820 signature by line wrapping the base64 encoded structure and surrounding
823 -----BEGIN PKCS7-----
826 and using the command,
828 openssl cms -verify -inform PEM -in signature.pem -content content.txt
830 alternatively you can base64 decode the signature and use
832 openssl cms -verify -inform DER -in signature.der -content content.txt
834 Create an encrypted message using 128 bit Camellia:
836 openssl cms -encrypt -in plain.txt -camellia128 -out mail.msg cert.pem
838 Add a signer to an existing message:
840 openssl cms -resign -in mail.msg -signer newsign.pem -out mail2.msg
842 Sign a message using RSA-PSS:
844 openssl cms -sign -in message.txt -text -out mail.msg \
845 -signer mycert.pem -keyopt rsa_padding_mode:pss
847 Create an encrypted message using RSA-OAEP:
849 openssl cms -encrypt -in plain.txt -out mail.msg \
850 -recip cert.pem -keyopt rsa_padding_mode:oaep
852 Use SHA256 KDF with an ECDH certificate:
854 openssl cms -encrypt -in plain.txt -out mail.msg \
855 -recip ecdhcert.pem -keyopt ecdh_kdf_md:sha256
857 Print CMS signed binary data in human-readable form:
859 openssl cms -in signed.cms -binary -inform DER -cmsout -print
863 The MIME parser isn't very clever: it seems to handle most messages that I've
864 thrown at it but it may choke on others.
866 The code currently will only write out the signer's certificate to a file: if
867 the signer has a separate encryption certificate this must be manually
868 extracted. There should be some heuristic that determines the correct
869 encryption certificate.
871 Ideally a database should be maintained of a certificates for each email
874 The code doesn't currently take note of the permitted symmetric encryption
875 algorithms as supplied in the SMIMECapabilities signed attribute. this means the
876 user has to manually include the correct encryption algorithm. It should store
877 the list of permitted ciphers in a database and only use those.
879 No revocation checking is done on the signer's certificate.
883 L<ossl_store-file(7)>
887 The use of multiple B<-signer> options and the B<-resign> command were first
888 added in OpenSSL 1.0.0.
890 The B<-keyopt> option was added in OpenSSL 1.0.2.
892 Support for RSA-OAEP and RSA-PSS was added in OpenSSL 1.0.2.
894 The use of non-RSA keys with B<-encrypt> and B<-decrypt>
895 was added in OpenSSL 1.0.2.
897 The -no_alt_chains option was added in OpenSSL 1.0.2b.
899 The B<-nameopt> option was added in OpenSSL 3.0.0.
901 The B<-engine> option was deprecated in OpenSSL 3.0.
905 Copyright 2008-2021 The OpenSSL Project Authors. All Rights Reserved.
907 Licensed under the Apache License 2.0 (the "License"). You may not use
908 this file except in compliance with the License. You can obtain a copy
909 in the file LICENSE in the source distribution or at
910 L<https://www.openssl.org/source/license.html>.