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Commit | Line | Data |
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e3775a33 DSH |
1 | =pod |
2 | ||
3 | =head1 NAME | |
4 | ||
3f2181e6 | 5 | openssl-smime, |
e3775a33 DSH |
6 | smime - S/MIME utility |
7 | ||
8 | =head1 SYNOPSIS | |
9 | ||
10 | B<openssl> B<smime> | |
169394d4 | 11 | [B<-help>] |
e3775a33 DSH |
12 | [B<-encrypt>] |
13 | [B<-decrypt>] | |
14 | [B<-sign>] | |
d884c5ba | 15 | [B<-resign>] |
e3775a33 DSH |
16 | [B<-verify>] |
17 | [B<-pk7out>] | |
2197494d DSH |
18 | [B<-binary>] |
19 | [B<-crlfeol>] | |
e75138ab | 20 | [B<-I<cipher>>] |
e3775a33 | 21 | [B<-in file>] |
ce21d108 HK |
22 | [B<-CAfile file>] |
23 | [B<-CApath dir>] | |
40e2d76b MC |
24 | [B<-no-CAfile>] |
25 | [B<-no-CApath>] | |
e42d84be HK |
26 | [B<-attime timestamp>] |
27 | [B<-check_ss_sig>] | |
28 | [B<-crl_check>] | |
29 | [B<-crl_check_all>] | |
30 | [B<-explicit_policy>] | |
31 | [B<-extended_crl>] | |
32 | [B<-ignore_critical>] | |
33 | [B<-inhibit_any>] | |
34 | [B<-inhibit_map>] | |
e42d84be HK |
35 | [B<-partial_chain>] |
36 | [B<-policy arg>] | |
37 | [B<-policy_check>] | |
38 | [B<-policy_print>] | |
39 | [B<-purpose purpose>] | |
40 | [B<-suiteB_128>] | |
41 | [B<-suiteB_128_only>] | |
42 | [B<-suiteB_192>] | |
6d3d5793 | 43 | [B<-trusted_first>] |
fa7b0111 | 44 | [B<-no_alt_chains>] |
e42d84be | 45 | [B<-use_deltas>] |
fbb82a60 | 46 | [B<-auth_level num>] |
e42d84be HK |
47 | [B<-verify_depth num>] |
48 | [B<-verify_email email>] | |
49 | [B<-verify_hostname hostname>] | |
50 | [B<-verify_ip ip>] | |
51 | [B<-verify_name name>] | |
52 | [B<-x509_strict>] | |
e3775a33 DSH |
53 | [B<-certfile file>] |
54 | [B<-signer file>] | |
55 | [B<-recip file>] | |
fd13f0ee | 56 | [B<-inform SMIME|PEM|DER>] |
84b65340 | 57 | [B<-passin arg>] |
48b53522 | 58 | [B<-inkey file_or_id>] |
e3775a33 | 59 | [B<-out file>] |
fd13f0ee DSH |
60 | [B<-outform SMIME|PEM|DER>] |
61 | [B<-content file>] | |
e3775a33 DSH |
62 | [B<-to addr>] |
63 | [B<-from ad>] | |
64 | [B<-subject s>] | |
65 | [B<-text>] | |
76b46e77 DSH |
66 | [B<-indef>] |
67 | [B<-noindef>] | |
68 | [B<-stream>] | |
3ee1eac2 RS |
69 | [B<-rand file...>] |
70 | [B<-writerand file>] | |
d884c5ba | 71 | [B<-md digest>] |
e3775a33 DSH |
72 | [cert.pem]... |
73 | ||
74 | =head1 DESCRIPTION | |
75 | ||
76 | The B<smime> command handles S/MIME mail. It can encrypt, decrypt, sign and | |
77 | verify S/MIME messages. | |
78 | ||
3dfda1a6 | 79 | =head1 OPTIONS |
e3775a33 | 80 | |
76b46e77 | 81 | There are six operation options that set the type of operation to be performed. |
e3775a33 DSH |
82 | The meaning of the other options varies according to the operation type. |
83 | ||
84 | =over 4 | |
85 | ||
169394d4 MR |
86 | =item B<-help> |
87 | ||
88 | Print out a usage message. | |
89 | ||
e3775a33 DSH |
90 | =item B<-encrypt> |
91 | ||
c4de074e | 92 | Encrypt mail for the given recipient certificates. Input file is the message |
e3775a33 DSH |
93 | to be encrypted. The output file is the encrypted mail in MIME format. |
94 | ||
2a9afa40 RS |
95 | Note that no revocation check is done for the recipient cert, so if that |
96 | key has been compromised, others may be able to decrypt the text. | |
97 | ||
e3775a33 DSH |
98 | =item B<-decrypt> |
99 | ||
c4de074e | 100 | Decrypt mail using the supplied certificate and private key. Expects an |
e3775a33 DSH |
101 | encrypted mail message in MIME format for the input file. The decrypted mail |
102 | is written to the output file. | |
103 | ||
104 | =item B<-sign> | |
105 | ||
c4de074e | 106 | Sign mail using the supplied certificate and private key. Input file is |
e3775a33 DSH |
107 | the message to be signed. The signed message in MIME format is written |
108 | to the output file. | |
109 | ||
110 | =item B<-verify> | |
111 | ||
c4de074e | 112 | Verify signed mail. Expects a signed mail message on input and outputs |
e3775a33 DSH |
113 | the signed data. Both clear text and opaque signing is supported. |
114 | ||
115 | =item B<-pk7out> | |
116 | ||
c4de074e | 117 | Takes an input message and writes out a PEM encoded PKCS#7 structure. |
e3775a33 | 118 | |
d884c5ba DSH |
119 | =item B<-resign> |
120 | ||
c4de074e | 121 | Resign a message: take an existing message and one or more new signers. |
d884c5ba | 122 | |
e3775a33 DSH |
123 | =item B<-in filename> |
124 | ||
c4de074e | 125 | The input message to be encrypted or signed or the MIME message to |
e3775a33 DSH |
126 | be decrypted or verified. |
127 | ||
fd13f0ee DSH |
128 | =item B<-inform SMIME|PEM|DER> |
129 | ||
c4de074e | 130 | This specifies the input format for the PKCS#7 structure. The default |
fd13f0ee DSH |
131 | is B<SMIME> which reads an S/MIME format message. B<PEM> and B<DER> |
132 | format change this to expect PEM and DER format PKCS#7 structures | |
133 | instead. This currently only affects the input format of the PKCS#7 | |
134 | structure, if no PKCS#7 structure is being input (for example with | |
135 | B<-encrypt> or B<-sign>) this option has no effect. | |
136 | ||
e3775a33 DSH |
137 | =item B<-out filename> |
138 | ||
c4de074e | 139 | The message text that has been decrypted or verified or the output MIME |
e3775a33 DSH |
140 | format message that has been signed or verified. |
141 | ||
fd13f0ee DSH |
142 | =item B<-outform SMIME|PEM|DER> |
143 | ||
c4de074e | 144 | This specifies the output format for the PKCS#7 structure. The default |
fd13f0ee DSH |
145 | is B<SMIME> which write an S/MIME format message. B<PEM> and B<DER> |
146 | format change this to write PEM and DER format PKCS#7 structures | |
147 | instead. This currently only affects the output format of the PKCS#7 | |
148 | structure, if no PKCS#7 structure is being output (for example with | |
149 | B<-verify> or B<-decrypt>) this option has no effect. | |
150 | ||
76b46e77 DSH |
151 | =item B<-stream -indef -noindef> |
152 | ||
c4de074e | 153 | The B<-stream> and B<-indef> options are equivalent and enable streaming I/O |
76b46e77 DSH |
154 | for encoding operations. This permits single pass processing of data without |
155 | the need to hold the entire contents in memory, potentially supporting very | |
156 | large files. Streaming is automatically set for S/MIME signing with detached | |
157 | data if the output format is B<SMIME> it is currently off by default for all | |
158 | other operations. | |
159 | ||
160 | =item B<-noindef> | |
161 | ||
c4de074e | 162 | Disable streaming I/O where it would produce and indefinite length constructed |
76b46e77 DSH |
163 | encoding. This option currently has no effect. In future streaming will be |
164 | enabled by default on all relevant operations and this option will disable it. | |
165 | ||
fd13f0ee DSH |
166 | =item B<-content filename> |
167 | ||
168 | This specifies a file containing the detached content, this is only | |
169 | useful with the B<-verify> command. This is only usable if the PKCS#7 | |
170 | structure is using the detached signature form where the content is | |
171 | not included. This option will override any content if the input format | |
172 | is S/MIME and it uses the multipart/signed MIME content type. | |
173 | ||
e3775a33 DSH |
174 | =item B<-text> |
175 | ||
c4de074e | 176 | This option adds plain text (text/plain) MIME headers to the supplied |
e3775a33 | 177 | message if encrypting or signing. If decrypting or verifying it strips |
1bc74519 | 178 | off text headers: if the decrypted or verified message is not of MIME |
e3775a33 DSH |
179 | type text/plain then an error occurs. |
180 | ||
181 | =item B<-CAfile file> | |
182 | ||
c4de074e | 183 | A file containing trusted CA certificates, only used with B<-verify>. |
e3775a33 DSH |
184 | |
185 | =item B<-CApath dir> | |
186 | ||
c4de074e | 187 | A directory containing trusted CA certificates, only used with |
e3775a33 DSH |
188 | B<-verify>. This directory must be a standard certificate directory: that |
189 | is a hash of each subject name (using B<x509 -hash>) should be linked | |
190 | to each certificate. | |
191 | ||
40e2d76b MC |
192 | =item B<-no-CAfile> |
193 | ||
c4de074e | 194 | Do not load the trusted CA certificates from the default file location. |
40e2d76b MC |
195 | |
196 | =item B<-no-CApath> | |
197 | ||
c4de074e | 198 | Do not load the trusted CA certificates from the default directory location. |
40e2d76b | 199 | |
d884c5ba DSH |
200 | =item B<-md digest> |
201 | ||
c4de074e | 202 | Digest algorithm to use when signing or resigning. If not present then the |
d884c5ba DSH |
203 | default digest algorithm for the signing key will be used (usually SHA1). |
204 | ||
e75138ab | 205 | =item B<-I<cipher>> |
e3775a33 | 206 | |
c4de074e | 207 | The encryption algorithm to use. For example DES (56 bits) - B<-des>, |
e5fa864f | 208 | triple DES (168 bits) - B<-des3>, |
1bc74519 | 209 | EVP_get_cipherbyname() function) can also be used preceded by a dash, for |
9446daac | 210 | example B<-aes-128-cbc>. See L<B<enc>|enc(1)> for list of ciphers |
e5fa864f | 211 | supported by your version of OpenSSL. |
d884c5ba | 212 | |
6f719f06 | 213 | If not specified triple DES is used. Only used with B<-encrypt>. |
e3775a33 DSH |
214 | |
215 | =item B<-nointern> | |
216 | ||
c4de074e | 217 | When verifying a message normally certificates (if any) included in |
e3775a33 DSH |
218 | the message are searched for the signing certificate. With this option |
219 | only the certificates specified in the B<-certfile> option are used. | |
220 | The supplied certificates can still be used as untrusted CAs however. | |
221 | ||
222 | =item B<-noverify> | |
223 | ||
c4de074e | 224 | Do not verify the signers certificate of a signed message. |
e3775a33 DSH |
225 | |
226 | =item B<-nochain> | |
227 | ||
c4de074e | 228 | Do not do chain verification of signers certificates: that is don't |
e3775a33 DSH |
229 | use the certificates in the signed message as untrusted CAs. |
230 | ||
231 | =item B<-nosigs> | |
232 | ||
c4de074e | 233 | Don't try to verify the signatures on the message. |
e3775a33 DSH |
234 | |
235 | =item B<-nocerts> | |
236 | ||
c4de074e | 237 | When signing a message the signer's certificate is normally included |
e3775a33 DSH |
238 | with this option it is excluded. This will reduce the size of the |
239 | signed message but the verifier must have a copy of the signers certificate | |
240 | available locally (passed using the B<-certfile> option for example). | |
241 | ||
242 | =item B<-noattr> | |
243 | ||
c4de074e | 244 | Normally when a message is signed a set of attributes are included which |
e3775a33 DSH |
245 | include the signing time and supported symmetric algorithms. With this |
246 | option they are not included. | |
247 | ||
248 | =item B<-binary> | |
249 | ||
c4de074e | 250 | Normally the input message is converted to "canonical" format which is |
3fc9635e DSH |
251 | effectively using CR and LF as end of line: as required by the S/MIME |
252 | specification. When this option is present no translation occurs. This | |
253 | is useful when handling binary data which may not be in MIME format. | |
e3775a33 | 254 | |
2197494d DSH |
255 | =item B<-crlfeol> |
256 | ||
c4de074e | 257 | Normally the output file uses a single B<LF> as end of line. When this |
2197494d DSH |
258 | option is present B<CRLF> is used instead. |
259 | ||
e3775a33 DSH |
260 | =item B<-nodetach> |
261 | ||
c4de074e | 262 | When signing a message use opaque signing: this form is more resistant |
e3775a33 DSH |
263 | to translation by mail relays but it cannot be read by mail agents that |
264 | do not support S/MIME. Without this option cleartext signing with | |
265 | the MIME type multipart/signed is used. | |
266 | ||
267 | =item B<-certfile file> | |
268 | ||
c4de074e | 269 | Allows additional certificates to be specified. When signing these will |
e3775a33 DSH |
270 | be included with the message. When verifying these will be searched for |
271 | the signers certificates. The certificates should be in PEM format. | |
272 | ||
273 | =item B<-signer file> | |
274 | ||
c4de074e | 275 | A signing certificate when signing or resigning a message, this option can be |
d884c5ba DSH |
276 | used multiple times if more than one signer is required. If a message is being |
277 | verified then the signers certificates will be written to this file if the | |
278 | verification was successful. | |
e3775a33 DSH |
279 | |
280 | =item B<-recip file> | |
281 | ||
c4de074e | 282 | The recipients certificate when decrypting a message. This certificate |
e3775a33 DSH |
283 | must match one of the recipients of the message or an error occurs. |
284 | ||
48b53522 | 285 | =item B<-inkey file_or_id> |
e3775a33 | 286 | |
c4de074e | 287 | The private key to use when signing or decrypting. This must match the |
e3775a33 DSH |
288 | corresponding certificate. If this option is not specified then the |
289 | private key must be included in the certificate file specified with | |
d884c5ba DSH |
290 | the B<-recip> or B<-signer> file. When signing this option can be used |
291 | multiple times to specify successive keys. | |
48b53522 RS |
292 | If no engine is used, the argument is taken as a file; if an engine is |
293 | specified, the argument is given to the engine as a key identifier. | |
e3775a33 | 294 | |
84b65340 DSH |
295 | =item B<-passin arg> |
296 | ||
c4de074e | 297 | The private key password source. For more information about the format of B<arg> |
9b86974e | 298 | see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)>. |
84b65340 | 299 | |
3ee1eac2 | 300 | =item B<-rand file...> |
d13e4eb0 | 301 | |
c4de074e | 302 | A file or files containing random data used to seed the random number |
3ee1eac2 | 303 | generator. |
35ed393e | 304 | Multiple files can be specified separated by an OS-dependent character. |
b87ef946 | 305 | The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for |
a4cfd178 | 306 | all others. |
d13e4eb0 | 307 | |
3ee1eac2 RS |
308 | =item [B<-writerand file>] |
309 | ||
310 | Writes random data to the specified I<file> upon exit. | |
311 | This can be used with a subsequent B<-rand> flag. | |
312 | ||
e3775a33 DSH |
313 | =item B<cert.pem...> |
314 | ||
c4de074e | 315 | One or more certificates of message recipients: used when encrypting |
1bc74519 | 316 | a message. |
e3775a33 DSH |
317 | |
318 | =item B<-to, -from, -subject> | |
319 | ||
c4de074e | 320 | The relevant mail headers. These are included outside the signed |
e3775a33 DSH |
321 | portion of a message so they may be included manually. If signing |
322 | then many S/MIME mail clients check the signers certificate's email | |
323 | address matches that specified in the From: address. | |
324 | ||
e42d84be | 325 | =item B<-attime>, B<-check_ss_sig>, B<-crl_check>, B<-crl_check_all>, |
d33def66 VD |
326 | B<-explicit_policy>, B<-extended_crl>, B<-ignore_critical>, B<-inhibit_any>, |
327 | B<-inhibit_map>, B<-no_alt_chains>, B<-partial_chain>, B<-policy>, | |
e42d84be | 328 | B<-policy_check>, B<-policy_print>, B<-purpose>, B<-suiteB_128>, |
d33def66 | 329 | B<-suiteB_128_only>, B<-suiteB_192>, B<-trusted_first>, B<-use_deltas>, |
fbb82a60 VD |
330 | B<-auth_level>, B<-verify_depth>, B<-verify_email>, B<-verify_hostname>, |
331 | B<-verify_ip>, B<-verify_name>, B<-x509_strict> | |
e5fa864f DSH |
332 | |
333 | Set various options of certificate chain verification. See | |
9b86974e | 334 | L<verify(1)> manual page for details. |
e5fa864f | 335 | |
e3775a33 DSH |
336 | =back |
337 | ||
338 | =head1 NOTES | |
339 | ||
340 | The MIME message must be sent without any blank lines between the | |
341 | headers and the output. Some mail programs will automatically add | |
342 | a blank line. Piping the mail directly to sendmail is one way to | |
343 | achieve the correct format. | |
344 | ||
3fc9635e | 345 | The supplied message to be signed or encrypted must include the |
60250017 | 346 | necessary MIME headers or many S/MIME clients won't display it |
3fc9635e DSH |
347 | properly (if at all). You can use the B<-text> option to automatically |
348 | add plain text headers. | |
349 | ||
e3775a33 DSH |
350 | A "signed and encrypted" message is one where a signed message is |
351 | then encrypted. This can be produced by encrypting an already signed | |
3fc9635e | 352 | message: see the examples section. |
e3775a33 DSH |
353 | |
354 | This version of the program only allows one signer per message but it | |
355 | will verify multiple signers on received messages. Some S/MIME clients | |
19d2bb57 | 356 | choke if a message contains multiple signers. It is possible to sign |
e3775a33 DSH |
357 | messages "in parallel" by signing an already signed message. |
358 | ||
3fc9635e DSH |
359 | The options B<-encrypt> and B<-decrypt> reflect common usage in S/MIME |
360 | clients. Strictly speaking these process PKCS#7 enveloped data: PKCS#7 | |
361 | encrypted data is used for other purposes. | |
362 | ||
d884c5ba DSH |
363 | The B<-resign> option uses an existing message digest when adding a new |
364 | signer. This means that attributes must be present in at least one existing | |
365 | signer using the same message digest or this operation will fail. | |
366 | ||
e4ef2e25 | 367 | The B<-stream> and B<-indef> options enable streaming I/O support. |
76b46e77 DSH |
368 | As a result the encoding is BER using indefinite length constructed encoding |
369 | and no longer DER. Streaming is supported for the B<-encrypt> operation and the | |
370 | B<-sign> operation if the content is not detached. | |
371 | ||
372 | Streaming is always used for the B<-sign> operation with detached data but | |
373 | since the content is no longer part of the PKCS#7 structure the encoding | |
374 | remains DER. | |
375 | ||
e3775a33 DSH |
376 | =head1 EXIT CODES |
377 | ||
378 | =over 4 | |
379 | ||
c8919dde | 380 | =item Z<>0 |
e3775a33 | 381 | |
c4de074e | 382 | The operation was completely successfully. |
e3775a33 | 383 | |
c8919dde | 384 | =item Z<>1 |
e3775a33 | 385 | |
c4de074e | 386 | An error occurred parsing the command options. |
e3775a33 | 387 | |
c8919dde | 388 | =item Z<>2 |
e3775a33 | 389 | |
c4de074e | 390 | One of the input files could not be read. |
e3775a33 | 391 | |
c8919dde | 392 | =item Z<>3 |
e3775a33 | 393 | |
c4de074e | 394 | An error occurred creating the PKCS#7 file or when reading the MIME |
e3775a33 DSH |
395 | message. |
396 | ||
c8919dde | 397 | =item Z<>4 |
e3775a33 | 398 | |
c4de074e | 399 | An error occurred decrypting or verifying the message. |
e3775a33 | 400 | |
c8919dde | 401 | =item Z<>5 |
e3775a33 | 402 | |
c4de074e | 403 | The message was verified correctly but an error occurred writing out |
e3775a33 DSH |
404 | the signers certificates. |
405 | ||
406 | =back | |
407 | ||
408 | =head1 EXAMPLES | |
409 | ||
3fc9635e DSH |
410 | Create a cleartext signed message: |
411 | ||
1675f6eb | 412 | openssl smime -sign -in message.txt -text -out mail.msg \ |
1bc74519 | 413 | -signer mycert.pem |
3fc9635e | 414 | |
0d638dc1 | 415 | Create an opaque signed message: |
3fc9635e | 416 | |
1675f6eb | 417 | openssl smime -sign -in message.txt -text -out mail.msg -nodetach \ |
1bc74519 | 418 | -signer mycert.pem |
3fc9635e DSH |
419 | |
420 | Create a signed message, include some additional certificates and | |
421 | read the private key from another file: | |
422 | ||
1675f6eb | 423 | openssl smime -sign -in in.txt -text -out mail.msg \ |
1bc74519 | 424 | -signer mycert.pem -inkey mykey.pem -certfile mycerts.pem |
3fc9635e | 425 | |
d884c5ba DSH |
426 | Create a signed message with two signers: |
427 | ||
428 | openssl smime -sign -in message.txt -text -out mail.msg \ | |
1bc74519 | 429 | -signer mycert.pem -signer othercert.pem |
d884c5ba | 430 | |
3fc9635e DSH |
431 | Send a signed message under Unix directly to sendmail, including headers: |
432 | ||
1675f6eb | 433 | openssl smime -sign -in in.txt -text -signer mycert.pem \ |
1bc74519 RS |
434 | -from steve@openssl.org -to someone@somewhere \ |
435 | -subject "Signed message" | sendmail someone@somewhere | |
3fc9635e DSH |
436 | |
437 | Verify a message and extract the signer's certificate if successful: | |
438 | ||
439 | openssl smime -verify -in mail.msg -signer user.pem -out signedtext.txt | |
440 | ||
441 | Send encrypted mail using triple DES: | |
442 | ||
1675f6eb | 443 | openssl smime -encrypt -in in.txt -from steve@openssl.org \ |
1bc74519 RS |
444 | -to someone@somewhere -subject "Encrypted message" \ |
445 | -des3 user.pem -out mail.msg | |
3fc9635e DSH |
446 | |
447 | Sign and encrypt mail: | |
448 | ||
1675f6eb | 449 | openssl smime -sign -in ml.txt -signer my.pem -text \ |
1bc74519 RS |
450 | | openssl smime -encrypt -out mail.msg \ |
451 | -from steve@openssl.org -to someone@somewhere \ | |
452 | -subject "Signed and Encrypted message" -des3 user.pem | |
3fc9635e | 453 | |
d884c5ba DSH |
454 | Note: the encryption command does not include the B<-text> option because the |
455 | message being encrypted already has MIME headers. | |
3fc9635e DSH |
456 | |
457 | Decrypt mail: | |
458 | ||
459 | openssl smime -decrypt -in mail.msg -recip mycert.pem -inkey key.pem | |
460 | ||
fd13f0ee DSH |
461 | The output from Netscape form signing is a PKCS#7 structure with the |
462 | detached signature format. You can use this program to verify the | |
463 | signature by line wrapping the base64 encoded structure and surrounding | |
464 | it with: | |
465 | ||
a8c12555 DSH |
466 | -----BEGIN PKCS7----- |
467 | -----END PKCS7----- | |
fd13f0ee | 468 | |
1bc74519 | 469 | and using the command: |
fd13f0ee DSH |
470 | |
471 | openssl smime -verify -inform PEM -in signature.pem -content content.txt | |
472 | ||
0d638dc1 | 473 | Alternatively you can base64 decode the signature and use: |
fd13f0ee DSH |
474 | |
475 | openssl smime -verify -inform DER -in signature.der -content content.txt | |
476 | ||
f3dea9a5 BM |
477 | Create an encrypted message using 128 bit Camellia: |
478 | ||
479 | openssl smime -encrypt -in plain.txt -camellia128 -out mail.msg cert.pem | |
480 | ||
d884c5ba DSH |
481 | Add a signer to an existing message: |
482 | ||
483 | openssl smime -resign -in mail.msg -signer newsign.pem -out mail2.msg | |
484 | ||
3fc9635e DSH |
485 | =head1 BUGS |
486 | ||
d884c5ba DSH |
487 | The MIME parser isn't very clever: it seems to handle most messages that I've |
488 | thrown at it but it may choke on others. | |
3fc9635e | 489 | |
d884c5ba DSH |
490 | The code currently will only write out the signer's certificate to a file: if |
491 | the signer has a separate encryption certificate this must be manually | |
492 | extracted. There should be some heuristic that determines the correct | |
493 | encryption certificate. | |
3fc9635e | 494 | |
d884c5ba DSH |
495 | Ideally a database should be maintained of a certificates for each email |
496 | address. | |
3fc9635e DSH |
497 | |
498 | The code doesn't currently take note of the permitted symmetric encryption | |
7e0de9e8 | 499 | algorithms as supplied in the SMIMECapabilities signed attribute. This means the |
3fc9635e DSH |
500 | user has to manually include the correct encryption algorithm. It should store |
501 | the list of permitted ciphers in a database and only use those. | |
502 | ||
503 | No revocation checking is done on the signer's certificate. | |
504 | ||
505 | The current code can only handle S/MIME v2 messages, the more complex S/MIME v3 | |
506 | structures may cause parsing errors. | |
e3775a33 | 507 | |
d884c5ba DSH |
508 | =head1 HISTORY |
509 | ||
510 | The use of multiple B<-signer> options and the B<-resign> command were first | |
fb552ac6 | 511 | added in OpenSSL 1.0.0 |
d884c5ba | 512 | |
fa7b0111 | 513 | The -no_alt_chains options was first added to OpenSSL 1.1.0. |
d884c5ba | 514 | |
e2f92610 RS |
515 | =head1 COPYRIGHT |
516 | ||
c4de074e | 517 | Copyright 2000-2017 The OpenSSL Project Authors. All Rights Reserved. |
e2f92610 | 518 | |
449040b4 | 519 | Licensed under the Apache License 2.0 (the "License"). You may not use |
e2f92610 RS |
520 | this file except in compliance with the License. You can obtain a copy |
521 | in the file LICENSE in the source distribution or at | |
522 | L<https://www.openssl.org/source/license.html>. | |
523 | ||
524 | =cut |