1CMS(1) OpenSSL CMS(1)
2
6 cms - CMS utility
7
9 openssl cms [-encrypt] [-decrypt] [-sign] [-verify] [-cmsout] [-resign]
10 [-data_create] [-data_out] [-digest_create] [-digest_verify]
11 [-compress] [-uncompress] [-EncryptedData_encrypt] [-sign_receipt]
12 [-verify_receipt receipt] [-in filename] [-inform SMIME|PEM|DER]
13 [-rctform SMIME|PEM|DER] [-out filename] [-outform SMIME|PEM|DER]
14 [-stream -indef -noindef] [-noindef] [-content filename] [-text]
15 [-noout] [-print] [-CAfile file] [-CApath dir] [-trusted_first]
16 [-no_alt_chains] [-md digest] [-[cipher]] [-nointern]
17 [-no_signer_cert_verify] [-nocerts] [-noattr] [-nosmimecap] [-binary]
18 [-nodetach] [-certfile file] [-certsout file] [-signer file] [-recip
19 file] [-keyid] [-receipt_request_all -receipt_request_first]
20 [-receipt_request_from emailaddress] [-receipt_request_to emailaddress]
21 [-receipt_request_print] [-secretkey key] [-secretkeyid id]
22 [-econtent_type type] [-inkey file] [-keyopt name:parameter] [-passin
23 arg] [-rand file(s)] [cert.pem...] [-to addr] [-from addr] [-subject
24 subj] [cert.pem]...
25
27 The cms command handles S/MIME v3.1 mail. It can encrypt, decrypt, sign
28 and verify, compress and uncompress S/MIME messages.
29
31 There are fourteen operation options that set the type of operation to
32 be performed. The meaning of the other options varies according to the
33 operation type.
34 -encrypt
36 encrypt mail for the given recipient certificates. Input file is
37 the message to be encrypted. The output file is the encrypted mail
38 in MIME format. The actual CMS type is <B>EnvelopedData<B>.
39 Note that no revocation check is done for the recipient cert, so if
41 that key has been compromised, others may be able to decrypt the
42 text.
43 -decrypt
45 decrypt mail using the supplied certificate and private key.
46 Expects an encrypted mail message in MIME format for the input
47 file. The decrypted mail is written to the output file.
48 -debug_decrypt
50 this option sets the CMS_DEBUG_DECRYPT flag. This option should be
51 used with caution: see the notes section below.
52 -sign
54 sign mail using the supplied certificate and private key. Input
55 file is the message to be signed. The signed message in MIME format
56 is written to the output file.
57 -verify
59 verify signed mail. Expects a signed mail message on input and
60 outputs the signed data. Both clear text and opaque signing is
61 supported.
62 -cmsout
64 takes an input message and writes out a PEM encoded CMS structure.
65 -resign
67 resign a message: take an existing message and one or more new
68 signers.
69 -data_create
71 Create a CMS Data type.
72 -data_out
74 Data type and output the content.
75 -digest_create
77 Create a CMS DigestedData type.
78 -digest_verify
80 Verify a CMS DigestedData type and output the content.
81 -compress
83 Create a CMS CompressedData type. OpenSSL must be compiled with
84 zlib support for this option to work, otherwise it will output an
85 error.
86 -uncompress
88 Uncompress a CMS CompressedData type and output the content.
89 OpenSSL must be compiled with zlib support for this option to work,
90 otherwise it will output an error.
91 -EncryptedData_encrypt
93 Encrypt content using supplied symmetric key and algorithm using a
94 CMS EncrytedData type and output the content.
95 -sign_receipt
97 Generate and output a signed receipt for the supplied message. The
98 input message must contain a signed receipt request. Functionality
99 is otherwise similar to the -sign operation.
100 -verify_receipt receipt
102 Verify a signed receipt in filename receipt. The input message must
103 contain the original receipt request. Functionality is otherwise
104 similar to the -verify operation.
105 -in filename
107 the input message to be encrypted or signed or the message to be
108 decrypted or verified.
109 -inform SMIME|PEM|DER
111 this specifies the input format for the CMS structure. The default
112 is SMIME which reads an S/MIME format message. PEM and DER format
113 change this to expect PEM and DER format CMS structures instead.
114 This currently only affects the input format of the CMS structure,
115 if no CMS structure is being input (for example with -encrypt or
116 -sign) this option has no effect.
117 -rctform SMIME|PEM|DER
119 specify the format for a signed receipt for use with the
120 -receipt_verify operation.
121 -out filename
123 the message text that has been decrypted or verified or the output
124 MIME format message that has been signed or verified.
125 -outform SMIME|PEM|DER
127 this specifies the output format for the CMS structure. The default
128 is SMIME which writes an S/MIME format message. PEM and DER format
129 change this to write PEM and DER format CMS structures instead.
130 This currently only affects the output format of the CMS structure,
131 if no CMS structure is being output (for example with -verify or
132 -decrypt) this option has no effect.
133 -stream -indef -noindef
135 the -stream and -indef options are equivalent and enable streaming
136 I/O for encoding operations. This permits single pass processing of
137 data without the need to hold the entire contents in memory,
138 potentially supporting very large files. Streaming is automatically
139 set for S/MIME signing with detached data if the output format is
140 SMIME it is currently off by default for all other operations.
141 -noindef
143 disable streaming I/O where it would produce and indefinite length
144 constructed encoding. This option currently has no effect. In
145 future streaming will be enabled by default on all relevant
146 operations and this option will disable it.
147 -content filename
149 This specifies a file containing the detached content, this is only
150 useful with the -verify command. This is only usable if the CMS
151 structure is using the detached signature form where the content is
152 not included. This option will override any content if the input
153 format is S/MIME and it uses the multipart/signed MIME content
154 type.
155 -text
157 this option adds plain text (text/plain) MIME headers to the
158 supplied message if encrypting or signing. If decrypting or
159 verifying it strips off text headers: if the decrypted or verified
160 message is not of MIME type text/plain then an error occurs.
161 -noout
163 for the -cmsout operation do not output the parsed CMS structure.
164 This is useful when combined with the -print option or if the
165 syntax of the CMS structure is being checked.
166 -print
168 for the -cmsout operation print out all fields of the CMS
169 structure. This is mainly useful for testing purposes.
170 -CAfile file
172 a file containing trusted CA certificates, only used with -verify.
173 -CApath dir
175 a directory containing trusted CA certificates, only used with
176 -verify. This directory must be a standard certificate directory:
177 that is a hash of each subject name (using x509 -hash) should be
178 linked to each certificate.
179 -trusted_first
181 Use certificates in CA file or CA directory before untrusted
182 certificates from the message when building the trust chain to
183 verify certificates. This is mainly useful in environments with
184 Bridge CA or Cross-Certified CAs.
185 -md digest
187 digest algorithm to use when signing or resigning. If not present
188 then the default digest algorithm for the signing key will be used
189 (usually SHA1).
190 -[cipher]
192 the encryption algorithm to use. For example triple DES (168 bits)
193 - -des3 or 256 bit AES - -aes256. Any standard algorithm name (as
194 used by the EVP_get_cipherbyname() function) can also be used
195 preceded by a dash, for example -aes_128_cbc. See enc for a list of
196 ciphers supported by your version of OpenSSL.
197 If not specified triple DES is used. Only used with -encrypt and
199 -EncryptedData_create commands.
200 -nointern
202 when verifying a message normally certificates (if any) included in
203 the message are searched for the signing certificate. With this
204 option only the certificates specified in the -certfile option are
205 used. The supplied certificates can still be used as untrusted CAs
206 however.
207 -no_signer_cert_verify
209 do not verify the signers certificate of a signed message.
210 -nocerts
212 when signing a message the signer's certificate is normally
213 included with this option it is excluded. This will reduce the size
214 of the signed message but the verifier must have a copy of the
215 signers certificate available locally (passed using the -certfile
216 option for example).
217 -noattr
219 normally when a message is signed a set of attributes are included
220 which include the signing time and supported symmetric algorithms.
221 With this option they are not included.
222 -nosmimecap
224 exclude the list of supported algorithms from signed attributes,
225 other options such as signing time and content type are still
226 included.
227 -binary
229 normally the input message is converted to "canonical" format which
230 is effectively using CR and LF as end of line: as required by the
231 S/MIME specification. When this option is present no translation
232 occurs. This is useful when handling binary data which may not be
233 in MIME format.
234 -nodetach
236 when signing a message use opaque signing: this form is more
237 resistant to translation by mail relays but it cannot be read by
238 mail agents that do not support S/MIME. Without this option
239 cleartext signing with the MIME type multipart/signed is used.
240 -certfile file
242 allows additional certificates to be specified. When signing these
243 will be included with the message. When verifying these will be
244 searched for the signers certificates. The certificates should be
245 in PEM format.
246 -certsout file
248 any certificates contained in the message are written to file.
249 -signer file
251 a signing certificate when signing or resigning a message, this
252 option can be used multiple times if more than one signer is
253 required. If a message is being verified then the signers
254 certificates will be written to this file if the verification was
255 successful.
256 -recip file
258 when decrypting a message this specifies the recipients
259 certificate. The certificate must match one of the recipients of
260 the message or an error occurs.
261 When encrypting a message this option may be used multiple times to
263 specify each recipient. This form must be used if customised
264 parameters are required (for example to specify RSA-OAEP).
265 -keyid
267 use subject key identifier to identify certificates instead of
268 issuer name and serial number. The supplied certificate must
269 include a subject key identifier extension. Supported by -sign and
270 -encrypt options.
271 -receipt_request_all -receipt_request_first
273 for -sign option include a signed receipt request. Indicate
274 requests should be provided by all receipient or first tier
275 recipients (those mailed directly and not from a mailing list).
276 Ignored it -receipt_request_from is included.
277 -receipt_request_from emailaddress
279 for -sign option include a signed receipt request. Add an explicit
280 email address where receipts should be supplied.
281 -receipt_request_to emailaddress
283 Add an explicit email address where signed receipts should be sent
284 to. This option must but supplied if a signed receipt it requested.
285 -receipt_request_print
287 For the -verify operation print out the contents of any signed
288 receipt requests.
289 -secretkey key
291 specify symmetric key to use. The key must be supplied in hex
292 format and be consistent with the algorithm used. Supported by the
293 -EncryptedData_encrypt -EncrryptedData_decrypt, -encrypt and
294 -decrypt options. When used with -encrypt or -decrypt the supplied
295 key is used to wrap or unwrap the content encryption key using an
296 AES key in the KEKRecipientInfo type.
297 -secretkeyid id
299 the key identifier for the supplied symmetric key for
300 KEKRecipientInfo type. This option must be present if the
301 -secretkey option is used with -encrypt. With -decrypt operations
302 the id is used to locate the relevant key if it is not supplied
303 then an attempt is used to decrypt any KEKRecipientInfo structures.
304 -econtent_type type
306 set the encapsulated content type to type if not supplied the Data
307 type is used. The type argument can be any valid OID name in either
308 text or numerical format.
309 -inkey file
311 the private key to use when signing or decrypting. This must match
312 the corresponding certificate. If this option is not specified then
313 the private key must be included in the certificate file specified
314 with the -recip or -signer file. When signing this option can be
315 used multiple times to specify successive keys.
316 -keyopt name:opt
318 for signing and encryption this option can be used multiple times
319 to set customised parameters for the preceding key or certificate.
320 It can currently be used to set RSA-PSS for signing, RSA-OAEP for
321 encryption or to modify default parameters for ECDH.
322 -passin arg
324 the private key password source. For more information about the
325 format of arg see the PASS PHRASE ARGUMENTS section in openssl(1).
326 -rand file(s)
328 a file or files containing random data used to seed the random
329 number generator, or an EGD socket (see RAND_egd(3)). Multiple
330 files can be specified separated by a OS-dependent character. The
331 separator is ; for MS-Windows, , for OpenVMS, and : for all others.
332 cert.pem...
334 one or more certificates of message recipients: used when
335 encrypting a message.
336 -to, -from, -subject
338 the relevant mail headers. These are included outside the signed
339 portion of a message so they may be included manually. If signing
340 then many S/MIME mail clients check the signers certificate's email
341 address matches that specified in the From: address.
342 -purpose, -ignore_critical, -issuer_checks, -crl_check, -crl_check_all,
344 -policy_check, -extended_crl, -x509_strict, -policy -check_ss_sig
345 -no_alt_chains
346 Set various certificate chain valiadition option. See the verify
347 manual page for details.
348
350 The MIME message must be sent without any blank lines between the
351 headers and the output. Some mail programs will automatically add a
352 blank line. Piping the mail directly to sendmail is one way to achieve
353 the correct format.
354 The supplied message to be signed or encrypted must include the
356 necessary MIME headers or many S/MIME clients wont display it properly
357 (if at all). You can use the -text option to automatically add plain
358 text headers.
359 A "signed and encrypted" message is one where a signed message is then
361 encrypted. This can be produced by encrypting an already signed
362 message: see the examples section.
363 This version of the program only allows one signer per message but it
365 will verify multiple signers on received messages. Some S/MIME clients
366 choke if a message contains multiple signers. It is possible to sign
367 messages "in parallel" by signing an already signed message.
368 The options -encrypt and -decrypt reflect common usage in S/MIME
370 clients. Strictly speaking these process CMS enveloped data: CMS
371 encrypted data is used for other purposes.
372 The -resign option uses an existing message digest when adding a new
374 signer. This means that attributes must be present in at least one
375 existing signer using the same message digest or this operation will
376 fail.
377 The -stream and -indef options enable experimental streaming I/O
379 support. As a result the encoding is BER using indefinite length
380 constructed encoding and no longer DER. Streaming is supported for the
381 -encrypt operation and the -sign operation if the content is not
382 detached.
383 Streaming is always used for the -sign operation with detached data but
385 since the content is no longer part of the CMS structure the encoding
386 remains DER.
387 If the -decrypt option is used without a recipient certificate then an
389 attempt is made to locate the recipient by trying each potential
390 recipient in turn using the supplied private key. To thwart the MMA
391 attack (Bleichenbacher's attack on PKCS #1 v1.5 RSA padding) all
392 recipients are tried whether they succeed or not and if no recipients
393 match the message is "decrypted" using a random key which will
394 typically output garbage. The -debug_decrypt option can be used to
395 disable the MMA attack protection and return an error if no recipient
396 can be found: this option should be used with caution. For a fuller
397 description see CMS_decrypt(3)).
398
400 0 the operation was completely successfully.
401 1 an error occurred parsing the command options.
403 2 one of the input files could not be read.
405 3 an error occurred creating the CMS file or when reading the MIME
407 message.
408 4 an error occurred decrypting or verifying the message.
410 5 the message was verified correctly but an error occurred writing
412 out the signers certificates.
413
415 The smime utility can only process the older PKCS#7 format. The cms
416 utility supports Cryptographic Message Syntax format. Use of some
417 features will result in messages which cannot be processed by
418 applications which only support the older format. These are detailed
419 below.
420 The use of the -keyid option with -sign or -encrypt.
422 The -outform PEM option uses different headers.
424 The -compress option.
426 The -secretkey option when used with -encrypt.
428 The use of PSS with -sign.
430 The use of OAEP or non-RSA keys with -encrypt.
432 Additionally the -EncryptedData_create and -data_create type cannot be
434 processed by the older smime command.
435
437 Create a cleartext signed message:
438 openssl cms -sign -in message.txt -text -out mail.msg \
440 -signer mycert.pem
441 Create an opaque signed message
443 openssl cms -sign -in message.txt -text -out mail.msg -nodetach \
445 -signer mycert.pem
446 Create a signed message, include some additional certificates and read
448 the private key from another file:
449 openssl cms -sign -in in.txt -text -out mail.msg \
451 -signer mycert.pem -inkey mykey.pem -certfile mycerts.pem
452 Create a signed message with two signers, use key identifier:
454 openssl cms -sign -in message.txt -text -out mail.msg \
456 -signer mycert.pem -signer othercert.pem -keyid
457 Send a signed message under Unix directly to sendmail, including
459 headers:
460 openssl cms -sign -in in.txt -text -signer mycert.pem \
462 -from steve@openssl.org -to someone@somewhere \
463 -subject "Signed message" | sendmail someone@somewhere
464 Verify a message and extract the signer's certificate if successful:
466 openssl cms -verify -in mail.msg -signer user.pem -out signedtext.txt
468 Send encrypted mail using triple DES:
470 openssl cms -encrypt -in in.txt -from steve@openssl.org \
472 -to someone@somewhere -subject "Encrypted message" \
473 -des3 user.pem -out mail.msg
474 Sign and encrypt mail:
476 openssl cms -sign -in ml.txt -signer my.pem -text \
478 | openssl cms -encrypt -out mail.msg \
479 -from steve@openssl.org -to someone@somewhere \
480 -subject "Signed and Encrypted message" -des3 user.pem
481 Note: the encryption command does not include the -text option because
483 the message being encrypted already has MIME headers.
484 Decrypt mail:
486 openssl cms -decrypt -in mail.msg -recip mycert.pem -inkey key.pem
488 The output from Netscape form signing is a PKCS#7 structure with the
490 detached signature format. You can use this program to verify the
491 signature by line wrapping the base64 encoded structure and surrounding
492 it with:
493 -----BEGIN PKCS7-----
495 -----END PKCS7-----
496 and using the command,
498 openssl cms -verify -inform PEM -in signature.pem -content content.txt
500 alternatively you can base64 decode the signature and use
502 openssl cms -verify -inform DER -in signature.der -content content.txt
504 Create an encrypted message using 128 bit Camellia:
506 openssl cms -encrypt -in plain.txt -camellia128 -out mail.msg cert.pem
508 Add a signer to an existing message:
510 openssl cms -resign -in mail.msg -signer newsign.pem -out mail2.msg
512 Sign mail using RSA-PSS:
514 openssl cms -sign -in message.txt -text -out mail.msg \
516 -signer mycert.pem -keyopt rsa_padding_mode:pss
517 Create encrypted mail using RSA-OAEP:
519 openssl cms -encrypt -in plain.txt -out mail.msg \
521 -recip cert.pem -keyopt rsa_padding_mode:oaep
522 Use SHA256 KDF with an ECDH certificate:
524 openssl cms -encrypt -in plain.txt -out mail.msg \
526 -recip ecdhcert.pem -keyopt ecdh_kdf_md:sha256
527
529 The MIME parser isn't very clever: it seems to handle most messages
530 that I've thrown at it but it may choke on others.
531 The code currently will only write out the signer's certificate to a
533 file: if the signer has a separate encryption certificate this must be
534 manually extracted. There should be some heuristic that determines the
535 correct encryption certificate.
536 Ideally a database should be maintained of a certificates for each
538 email address.
539 The code doesn't currently take note of the permitted symmetric
541 encryption algorithms as supplied in the SMIMECapabilities signed
542 attribute. this means the user has to manually include the correct
543 encryption algorithm. It should store the list of permitted ciphers in
544 a database and only use those.
545 No revocation checking is done on the signer's certificate.
547
549 The use of multiple -signer options and the -resign command were first
550 added in OpenSSL 1.0.0
551 The keyopt option was first added in OpenSSL 1.1.0
553 The use of -recip to specify the recipient when encrypting mail was
555 first added to OpenSSL 1.1.0
556 Support for RSA-OAEP and RSA-PSS was first added to OpenSSL 1.1.0.
558 The use of non-RSA keys with -encrypt and -decrypt was first added to
560 OpenSSL 1.1.0.
561 The -no_alt_chains options was first added to OpenSSL 1.0.2b.
5631.0.2k 2019-03-12 CMS(1)