2 {- OpenSSL::safe::output_do_not_edit_headers(); -}
6 openssl-cms - CMS utility
25 [B<-EncryptedData_encrypt>]
27 [B<-verify_receipt> I<receipt>]
30 [B<-inform> B<DER>|B<PEM>|B<SMIME>]
31 [B<-outform> B<DER>|B<PEM>|B<SMIME>]
32 [B<-rctform> B<DER>|B<PEM>|B<SMIME>]
33 [B<-keyform> B<DER>|B<PEM>|B<ENGINE>]
38 [B<-content> I<filename>]
53 [B<-certsout> I<file>]
57 [B<-receipt_request_all>]
58 [B<-receipt_request_first>]
59 [B<-receipt_request_from> I<emailaddress>]
60 [B<-receipt_request_to> I<emailaddress>]
61 [B<-receipt_request_print>]
62 [B<-secretkey> I<key>]
63 [B<-secretkeyid> I<id>]
64 [B<-econtent_type> I<type>]
66 [B<-keyopt> I<name>:I<parameter>]
71 {- $OpenSSL::safe::opt_v_synopsis -}
72 {- $OpenSSL::safe::opt_trust_synopsis -}
73 {- $OpenSSL::safe::opt_r_synopsis -}
76 =for openssl ifdef des-wrap engine
80 This command handles S/MIME v3.1 mail. It can encrypt, decrypt,
81 sign and verify, compress and uncompress S/MIME messages.
85 There are fourteen operation options that set the type of operation to be
86 performed. The meaning of the other options varies according to the operation
93 Print out a usage message.
97 Encrypt mail for the given recipient certificates. Input file is the message
98 to be encrypted. The output file is the encrypted mail in MIME format. The
99 actual CMS type is <B>EnvelopedData<B>.
101 Note that no revocation check is done for the recipient cert, so if that
102 key has been compromised, others may be able to decrypt the text.
106 Decrypt mail using the supplied certificate and private key. Expects an
107 encrypted mail message in MIME format for the input file. The decrypted mail
108 is written to the output file.
110 =item B<-debug_decrypt>
112 This option sets the B<CMS_DEBUG_DECRYPT> flag. This option should be used
113 with caution: see the notes section below.
117 Sign mail using the supplied certificate and private key. Input file is
118 the message to be signed. The signed message in MIME format is written
123 Verify signed mail. Expects a signed mail message on input and outputs
124 the signed data. Both clear text and opaque signing is supported.
128 Takes an input message and writes out a PEM encoded CMS structure.
132 Resign a message: take an existing message and one or more new signers.
136 Add an ESS signing-certificate or ESS signing-certificate-v2 signed-attribute to the SignerInfo, in order to make
137 the signature comply with the requirements for a CAdES Basic Electronic Signature (CAdES-BES). See the NOTES
138 section for more details.
140 =item B<-data_create>
142 Create a CMS B<Data> type.
146 B<Data> type and output the content.
148 =item B<-digest_create>
150 Create a CMS B<DigestedData> type.
152 =item B<-digest_verify>
154 Verify a CMS B<DigestedData> type and output the content.
158 Create a CMS B<CompressedData> type. OpenSSL must be compiled with B<zlib>
159 support for this option to work, otherwise it will output an error.
163 Uncompress a CMS B<CompressedData> type and output the content. OpenSSL must be
164 compiled with B<zlib> support for this option to work, otherwise it will
167 =item B<-EncryptedData_encrypt>
169 Encrypt content using supplied symmetric key and algorithm using a CMS
170 B<EncryptedData> type and output the content.
172 =item B<-sign_receipt>
174 Generate and output a signed receipt for the supplied message. The input
175 message B<must> contain a signed receipt request. Functionality is otherwise
176 similar to the B<-sign> operation.
178 =item B<-verify_receipt> I<receipt>
180 Verify a signed receipt in filename B<receipt>. The input message B<must>
181 contain the original receipt request. Functionality is otherwise similar
182 to the B<-verify> operation.
184 =item B<-in> I<filename>
186 The input message to be encrypted or signed or the message to be decrypted
189 =item B<-out> I<filename>
191 The message text that has been decrypted or verified or the output MIME
192 format message that has been signed or verified.
194 =item B<-inform> B<DER>|B<PEM>|B<SMIME>
196 The input format of the CMS structure (if one is being read);
197 the default is B<SMIME>.
198 See L<openssl(1)/Format Options> for details.
200 =item B<-outform> B<DER>|B<PEM>|B<SMIME>
202 The output format of the CMS structure (if one is being written);
203 the default is B<SMIME>.
204 See L<openssl(1)/Format Options> for details.
206 =item B<-keyform> B<DER>|B<PEM>|B<ENGINE>
208 The format of the private key file; the default is B<PEM>.
209 See L<openssl(1)/Format Options> for details.
211 =item B<-rctform> B<DER>|B<PEM>|B<SMIME>
213 The signed receipt format for use with the B<-receipt_verify>; the default
215 See L<openssl(1)/Format Options> for details.
217 =item B<-stream>, B<-indef>, B<-noindef>
219 The B<-stream> and B<-indef> options are equivalent and enable streaming I/O
220 for encoding operations. This permits single pass processing of data without
221 the need to hold the entire contents in memory, potentially supporting very
222 large files. Streaming is automatically set for S/MIME signing with detached
223 data if the output format is B<SMIME> it is currently off by default for all
228 Disable streaming I/O where it would produce and indefinite length constructed
229 encoding. This option currently has no effect. In future streaming will be
230 enabled by default on all relevant operations and this option will disable it.
232 =item B<-content> I<filename>
234 This specifies a file containing the detached content, this is only
235 useful with the B<-verify> command. This is only usable if the CMS
236 structure is using the detached signature form where the content is
237 not included. This option will override any content if the input format
238 is S/MIME and it uses the multipart/signed MIME content type.
242 This option adds plain text (text/plain) MIME headers to the supplied
243 message if encrypting or signing. If decrypting or verifying it strips
244 off text headers: if the decrypted or verified message is not of MIME
245 type text/plain then an error occurs.
249 For the B<-cmsout> operation do not output the parsed CMS structure. This
250 is useful when combined with the B<-print> option or if the syntax of the CMS
251 structure is being checked.
255 For the B<-cmsout> operation print out all fields of the CMS structure. This
256 is mainly useful for testing purposes.
258 =item B<-md> I<digest>
260 Digest algorithm to use when signing or resigning. If not present then the
261 default digest algorithm for the signing key will be used (usually SHA1).
265 The encryption algorithm to use. For example triple DES (168 bits) - B<-des3>
266 or 256 bit AES - B<-aes256>. Any standard algorithm name (as used by the
267 EVP_get_cipherbyname() function) can also be used preceded by a dash, for
268 example B<-aes-128-cbc>. See L<openssl-enc(1)> for a list of ciphers
269 supported by your version of OpenSSL.
271 If not specified triple DES is used. Only used with B<-encrypt> and
272 B<-EncryptedData_create> commands.
276 When verifying a message normally certificates (if any) included in
277 the message are searched for the signing certificate. With this option
278 only the certificates specified in the B<-certfile> option are used.
279 The supplied certificates can still be used as untrusted CAs however.
283 Do not verify the signers certificate of a signed message.
287 When signing a message the signer's certificate is normally included
288 with this option it is excluded. This will reduce the size of the
289 signed message but the verifier must have a copy of the signers certificate
290 available locally (passed using the B<-certfile> option for example).
294 Normally when a message is signed a set of attributes are included which
295 include the signing time and supported symmetric algorithms. With this
296 option they are not included.
300 Exclude the list of supported algorithms from signed attributes, other options
301 such as signing time and content type are still included.
305 Normally the input message is converted to "canonical" format which is
306 effectively using CR and LF as end of line: as required by the S/MIME
307 specification. When this option is present no translation occurs. This
308 is useful when handling binary data which may not be in MIME format.
312 Normally the output file uses a single B<LF> as end of line. When this
313 option is present B<CRLF> is used instead.
317 When signing use ASCII CRLF format canonicalisation. This strips trailing
318 whitespace from all lines, deletes trailing blank lines at EOF and sets
319 the encapsulated content type. This option is normally used with detached
320 content and an output signature format of DER. This option is not normally
321 needed when verifying as it is enabled automatically if the encapsulated
322 content format is detected.
326 When signing a message use opaque signing: this form is more resistant
327 to translation by mail relays but it cannot be read by mail agents that
328 do not support S/MIME. Without this option cleartext signing with
329 the MIME type multipart/signed is used.
331 =item B<-certfile> I<file>
333 Allows additional certificates to be specified. When signing these will
334 be included with the message. When verifying these will be searched for
335 the signers certificates. The certificates should be in PEM format.
337 =item B<-certsout> I<file>
339 Any certificates contained in the message are written to I<file>.
341 =item B<-signer> I<file>
343 A signing certificate when signing or resigning a message, this option can be
344 used multiple times if more than one signer is required. If a message is being
345 verified then the signers certificates will be written to this file if the
346 verification was successful.
348 =item B<-recip> I<file>
350 When decrypting a message this specifies the recipients certificate. The
351 certificate must match one of the recipients of the message or an error
354 When encrypting a message this option may be used multiple times to specify
355 each recipient. This form B<must> be used if customised parameters are
356 required (for example to specify RSA-OAEP).
358 Only certificates carrying RSA, Diffie-Hellman or EC keys are supported by this
363 Use subject key identifier to identify certificates instead of issuer name and
364 serial number. The supplied certificate B<must> include a subject key
365 identifier extension. Supported by B<-sign> and B<-encrypt> options.
367 =item B<-receipt_request_all>, B<-receipt_request_first>
369 For B<-sign> option include a signed receipt request. Indicate requests should
370 be provided by all recipient or first tier recipients (those mailed directly
371 and not from a mailing list). Ignored it B<-receipt_request_from> is included.
373 =item B<-receipt_request_from> I<emailaddress>
375 For B<-sign> option include a signed receipt request. Add an explicit email
376 address where receipts should be supplied.
378 =item B<-receipt_request_to> I<emailaddress>
380 Add an explicit email address where signed receipts should be sent to. This
381 option B<must> but supplied if a signed receipt it requested.
383 =item B<-receipt_request_print>
385 For the B<-verify> operation print out the contents of any signed receipt
388 =item B<-secretkey> I<key>
390 Specify symmetric key to use. The key must be supplied in hex format and be
391 consistent with the algorithm used. Supported by the B<-EncryptedData_encrypt>
392 B<-EncryptedData_decrypt>, B<-encrypt> and B<-decrypt> options. When used
393 with B<-encrypt> or B<-decrypt> the supplied key is used to wrap or unwrap the
394 content encryption key using an AES key in the B<KEKRecipientInfo> type.
396 =item B<-secretkeyid> I<id>
398 The key identifier for the supplied symmetric key for B<KEKRecipientInfo> type.
399 This option B<must> be present if the B<-secretkey> option is used with
400 B<-encrypt>. With B<-decrypt> operations the I<id> is used to locate the
401 relevant key if it is not supplied then an attempt is used to decrypt any
402 B<KEKRecipientInfo> structures.
404 =item B<-econtent_type> I<type>
406 Set the encapsulated content type to I<type> if not supplied the B<Data> type
407 is used. The I<type> argument can be any valid OID name in either text or
410 =item B<-inkey> I<file>
412 The private key to use when signing or decrypting. This must match the
413 corresponding certificate. If this option is not specified then the
414 private key must be included in the certificate file specified with
415 the B<-recip> or B<-signer> file. When signing this option can be used
416 multiple times to specify successive keys.
418 =item B<-keyopt> I<name>:I<parameter>
420 For signing and encryption this option can be used multiple times to
421 set customised parameters for the preceding key or certificate. It can
422 currently be used to set RSA-PSS for signing, RSA-OAEP for encryption
423 or to modify default parameters for ECDH.
425 =item B<-passin> I<arg>
427 The private key password source. For more information about the format of B<arg>
428 see L<openssl(1)/Pass Phrase Options>.
430 =item B<-to>, B<-from>, B<-subject>
432 The relevant mail headers. These are included outside the signed
433 portion of a message so they may be included manually. If signing
434 then many S/MIME mail clients check the signers certificate's email
435 address matches that specified in the From: address.
437 {- $OpenSSL::safe::opt_v_item -}
439 Any verification errors cause the command to exit.
441 {- $OpenSSL::safe::opt_trust_item -}
443 {- $OpenSSL::safe::opt_r_item -}
445 =item I<cert.pem> ...
447 One or more certificates of message recipients: used when encrypting
454 The MIME message must be sent without any blank lines between the
455 headers and the output. Some mail programs will automatically add
456 a blank line. Piping the mail directly to sendmail is one way to
457 achieve the correct format.
459 The supplied message to be signed or encrypted must include the
460 necessary MIME headers or many S/MIME clients won't display it
461 properly (if at all). You can use the B<-text> option to automatically
462 add plain text headers.
464 A "signed and encrypted" message is one where a signed message is
465 then encrypted. This can be produced by encrypting an already signed
466 message: see the examples section.
468 This version of the program only allows one signer per message but it
469 will verify multiple signers on received messages. Some S/MIME clients
470 choke if a message contains multiple signers. It is possible to sign
471 messages "in parallel" by signing an already signed message.
473 The options B<-encrypt> and B<-decrypt> reflect common usage in S/MIME
474 clients. Strictly speaking these process CMS enveloped data: CMS
475 encrypted data is used for other purposes.
477 The B<-resign> option uses an existing message digest when adding a new
478 signer. This means that attributes must be present in at least one existing
479 signer using the same message digest or this operation will fail.
481 The B<-stream> and B<-indef> options enable streaming I/O support.
482 As a result the encoding is BER using indefinite length constructed encoding
483 and no longer DER. Streaming is supported for the B<-encrypt> operation and the
484 B<-sign> operation if the content is not detached.
486 Streaming is always used for the B<-sign> operation with detached data but
487 since the content is no longer part of the CMS structure the encoding
490 If the B<-decrypt> option is used without a recipient certificate then an
491 attempt is made to locate the recipient by trying each potential recipient
492 in turn using the supplied private key. To thwart the MMA attack
493 (Bleichenbacher's attack on PKCS #1 v1.5 RSA padding) all recipients are
494 tried whether they succeed or not and if no recipients match the message
495 is "decrypted" using a random key which will typically output garbage.
496 The B<-debug_decrypt> option can be used to disable the MMA attack protection
497 and return an error if no recipient can be found: this option should be used
498 with caution. For a fuller description see L<CMS_decrypt(3)>).
500 =head1 CADES BASIC ELECTRONIC SIGNATURE (CADES-BES)
502 A CAdES Basic Electronic Signature (CAdES-BES), as defined in the European Standard ETSI EN 319 122-1 V1.1.1, contains:
508 The signed user data as defined in CMS (RFC 3852);
512 Content-type of the EncapsulatedContentInfo value being signed;
516 Message-digest of the eContent OCTET STRING within encapContentInfo being signed;
520 An ESS signing-certificate or ESS signing-certificate-v2 attribute, as defined in Enhanced Security Services (ESS), RFC 2634 and RFC 5035.
521 An ESS signing-certificate attribute only allows for the use of SHA-1 as a digest algorithm.
522 An ESS signing-certificate-v2 attribute allows for the use of any digest algorithm.
526 The digital signature value computed on the user data and, when present, on the signed attributes.
528 Note that currently the B<-cades> option applies only to the B<-sign> operation and is ignored during
529 the B<-verify> operation, i.e. the signing certification is not checked during the verification process.
530 This feature might be added in a future version.
540 The operation was completely successfully.
544 An error occurred parsing the command options.
548 One of the input files could not be read.
552 An error occurred creating the CMS file or when reading the MIME
557 An error occurred decrypting or verifying the message.
561 The message was verified correctly but an error occurred writing out
562 the signers certificates.
566 =head1 COMPATIBILITY WITH PKCS#7 FORMAT
568 L<openssl-smime(1)> can only process the older B<PKCS#7> format.
569 B<openssl cms> supports Cryptographic Message Syntax format.
570 Use of some features will result in messages which cannot be processed by
571 applications which only support the older format. These are detailed below.
573 The use of the B<-keyid> option with B<-sign> or B<-encrypt>.
575 The B<-outform> I<PEM> option uses different headers.
577 The B<-compress> option.
579 The B<-secretkey> option when used with B<-encrypt>.
581 The use of PSS with B<-sign>.
583 The use of OAEP or non-RSA keys with B<-encrypt>.
585 Additionally the B<-EncryptedData_create> and B<-data_create> type cannot
586 be processed by the older L<openssl-smime(1)> command.
590 Create a cleartext signed message:
592 openssl cms -sign -in message.txt -text -out mail.msg \
595 Create an opaque signed message
597 openssl cms -sign -in message.txt -text -out mail.msg -nodetach \
600 Create a signed message, include some additional certificates and
601 read the private key from another file:
603 openssl cms -sign -in in.txt -text -out mail.msg \
604 -signer mycert.pem -inkey mykey.pem -certfile mycerts.pem
606 Create a signed message with two signers, use key identifier:
608 openssl cms -sign -in message.txt -text -out mail.msg \
609 -signer mycert.pem -signer othercert.pem -keyid
611 Send a signed message under Unix directly to sendmail, including headers:
613 openssl cms -sign -in in.txt -text -signer mycert.pem \
614 -from steve@openssl.org -to someone@somewhere \
615 -subject "Signed message" | sendmail someone@somewhere
617 Verify a message and extract the signer's certificate if successful:
619 openssl cms -verify -in mail.msg -signer user.pem -out signedtext.txt
621 Send encrypted mail using triple DES:
623 openssl cms -encrypt -in in.txt -from steve@openssl.org \
624 -to someone@somewhere -subject "Encrypted message" \
625 -des3 user.pem -out mail.msg
627 Sign and encrypt mail:
629 openssl cms -sign -in ml.txt -signer my.pem -text \
630 | openssl cms -encrypt -out mail.msg \
631 -from steve@openssl.org -to someone@somewhere \
632 -subject "Signed and Encrypted message" -des3 user.pem
634 Note: the encryption command does not include the B<-text> option because the
635 message being encrypted already has MIME headers.
639 openssl cms -decrypt -in mail.msg -recip mycert.pem -inkey key.pem
641 The output from Netscape form signing is a PKCS#7 structure with the
642 detached signature format. You can use this program to verify the
643 signature by line wrapping the base64 encoded structure and surrounding
646 -----BEGIN PKCS7-----
649 and using the command,
651 openssl cms -verify -inform PEM -in signature.pem -content content.txt
653 alternatively you can base64 decode the signature and use
655 openssl cms -verify -inform DER -in signature.der -content content.txt
657 Create an encrypted message using 128 bit Camellia:
659 openssl cms -encrypt -in plain.txt -camellia128 -out mail.msg cert.pem
661 Add a signer to an existing message:
663 openssl cms -resign -in mail.msg -signer newsign.pem -out mail2.msg
665 Sign mail using RSA-PSS:
667 openssl cms -sign -in message.txt -text -out mail.msg \
668 -signer mycert.pem -keyopt rsa_padding_mode:pss
670 Create encrypted mail using RSA-OAEP:
672 openssl cms -encrypt -in plain.txt -out mail.msg \
673 -recip cert.pem -keyopt rsa_padding_mode:oaep
675 Use SHA256 KDF with an ECDH certificate:
677 openssl cms -encrypt -in plain.txt -out mail.msg \
678 -recip ecdhcert.pem -keyopt ecdh_kdf_md:sha256
682 The MIME parser isn't very clever: it seems to handle most messages that I've
683 thrown at it but it may choke on others.
685 The code currently will only write out the signer's certificate to a file: if
686 the signer has a separate encryption certificate this must be manually
687 extracted. There should be some heuristic that determines the correct
688 encryption certificate.
690 Ideally a database should be maintained of a certificates for each email
693 The code doesn't currently take note of the permitted symmetric encryption
694 algorithms as supplied in the SMIMECapabilities signed attribute. this means the
695 user has to manually include the correct encryption algorithm. It should store
696 the list of permitted ciphers in a database and only use those.
698 No revocation checking is done on the signer's certificate.
702 L<ossl_store-file(7)>
706 The use of multiple B<-signer> options and the B<-resign> command were first
707 added in OpenSSL 1.0.0.
709 The B<-keyopt> option was added in OpenSSL 1.0.2.
711 Support for RSA-OAEP and RSA-PSS was added in OpenSSL 1.0.2.
713 The use of non-RSA keys with B<-encrypt> and B<-decrypt>
714 was added in OpenSSL 1.0.2.
716 The -no_alt_chains option was added in OpenSSL 1.0.2b.
720 Copyright 2008-2019 The OpenSSL Project Authors. All Rights Reserved.
722 Licensed under the Apache License 2.0 (the "License"). You may not use
723 this file except in compliance with the License. You can obtain a copy
724 in the file LICENSE in the source distribution or at
725 L<https://www.openssl.org/source/license.html>.