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Commit | Line | Data |
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e3775a33 | 1 | =pod |
625c781d | 2 | {- OpenSSL::safe::output_do_not_edit_headers(); -} |
9fcb9702 | 3 | |
e3775a33 DSH |
4 | =head1 NAME |
5 | ||
4b537191 | 6 | openssl-smime - S/MIME command |
e3775a33 DSH |
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>] | |
8dc57d76 | 20 | [B<-I<cipher>>] |
e8769719 | 21 | [B<-in> I<file>] |
e8769719 RS |
22 | [B<-certfile> I<file>] |
23 | [B<-signer> I<file>] | |
65718c51 RS |
24 | [B<-nointern>] |
25 | [B<-noverify>] | |
26 | [B<-nochain>] | |
27 | [B<-nosigs>] | |
28 | [B<-nocerts>] | |
29 | [B<-noattr>] | |
30 | [B<-nodetach>] | |
31 | [B<-nosmimecap>] | |
e8769719 RS |
32 | [B<-recip> I< file>] |
33 | [B<-inform> B<DER>|B<PEM>|B<SMIME>] | |
777182a0 RS |
34 | [B<-outform> B<DER>|B<PEM>|B<SMIME>] |
35 | [B<-keyform> B<DER>|B<PEM>|B<ENGINE>] | |
e8769719 RS |
36 | [B<-passin> I<arg>] |
37 | [B<-inkey> I<file_or_id>] | |
38 | [B<-out> I<file>] | |
e8769719 RS |
39 | [B<-content> I<file>] |
40 | [B<-to> I<addr>] | |
41 | [B<-from> I<ad>] | |
42 | [B<-subject> I<s>] | |
e3775a33 | 43 | [B<-text>] |
76b46e77 DSH |
44 | [B<-indef>] |
45 | [B<-noindef>] | |
46 | [B<-stream>] | |
e8769719 | 47 | [B<-md> I<digest>] |
9fcb9702 | 48 | {- $OpenSSL::safe::opt_trust_synopsis -} |
65718c51 | 49 | {- $OpenSSL::safe::opt_engine_synopsis -} |
9fcb9702 | 50 | {- $OpenSSL::safe::opt_r_synopsis -} |
21d08b9e | 51 | {- $OpenSSL::safe::opt_v_synopsis -} |
6bd4e3f2 | 52 | {- $OpenSSL::safe::opt_provider_synopsis -} |
b1c0cc24 | 53 | I<cert.pem> ... |
e3775a33 | 54 | |
9f3c076b | 55 | =for openssl ifdef engine |
1738c0ce | 56 | |
e3775a33 DSH |
57 | =head1 DESCRIPTION |
58 | ||
35a810bb RL |
59 | This command handles S/MIME mail. It can encrypt, decrypt, sign |
60 | and verify S/MIME messages. | |
e3775a33 | 61 | |
3dfda1a6 | 62 | =head1 OPTIONS |
e3775a33 | 63 | |
76b46e77 | 64 | There are six operation options that set the type of operation to be performed. |
e3775a33 DSH |
65 | The meaning of the other options varies according to the operation type. |
66 | ||
67 | =over 4 | |
68 | ||
169394d4 MR |
69 | =item B<-help> |
70 | ||
71 | Print out a usage message. | |
72 | ||
e3775a33 DSH |
73 | =item B<-encrypt> |
74 | ||
c4de074e | 75 | Encrypt mail for the given recipient certificates. Input file is the message |
e3775a33 DSH |
76 | to be encrypted. The output file is the encrypted mail in MIME format. |
77 | ||
2a9afa40 RS |
78 | Note that no revocation check is done for the recipient cert, so if that |
79 | key has been compromised, others may be able to decrypt the text. | |
80 | ||
e3775a33 DSH |
81 | =item B<-decrypt> |
82 | ||
c4de074e | 83 | Decrypt mail using the supplied certificate and private key. Expects an |
e3775a33 DSH |
84 | encrypted mail message in MIME format for the input file. The decrypted mail |
85 | is written to the output file. | |
86 | ||
87 | =item B<-sign> | |
88 | ||
c4de074e | 89 | Sign mail using the supplied certificate and private key. Input file is |
e3775a33 DSH |
90 | the message to be signed. The signed message in MIME format is written |
91 | to the output file. | |
92 | ||
93 | =item B<-verify> | |
94 | ||
c4de074e | 95 | Verify signed mail. Expects a signed mail message on input and outputs |
e3775a33 DSH |
96 | the signed data. Both clear text and opaque signing is supported. |
97 | ||
98 | =item B<-pk7out> | |
99 | ||
c4de074e | 100 | Takes an input message and writes out a PEM encoded PKCS#7 structure. |
e3775a33 | 101 | |
d884c5ba DSH |
102 | =item B<-resign> |
103 | ||
c4de074e | 104 | Resign a message: take an existing message and one or more new signers. |
d884c5ba | 105 | |
e8769719 | 106 | =item B<-in> I<filename> |
e3775a33 | 107 | |
c4de074e | 108 | The input message to be encrypted or signed or the MIME message to |
e3775a33 DSH |
109 | be decrypted or verified. |
110 | ||
e8769719 | 111 | =item B<-out> I<filename> |
e3775a33 | 112 | |
c4de074e | 113 | The message text that has been decrypted or verified or the output MIME |
e3775a33 DSH |
114 | format message that has been signed or verified. |
115 | ||
777182a0 RS |
116 | =item B<-inform> B<DER>|B<PEM>|B<SMIME> |
117 | ||
118 | The input format of the PKCS#7 (S/MIME) structure (if one is being read); | |
119 | the default is B<SMIME>. | |
120 | See L<openssl(1)/Format Options> for details. | |
121 | ||
e8769719 | 122 | =item B<-outform> B<DER>|B<PEM>|B<SMIME> |
fd13f0ee | 123 | |
777182a0 RS |
124 | The output format of the PKCS#7 (S/MIME) structure (if one is being written); |
125 | the default is B<SMIME>. | |
126 | See L<openssl(1)/Format Options> for details. | |
127 | ||
128 | =item B<-keyform> B<DER>|B<PEM> | |
129 | ||
130 | The key format; the default is B<PEM>. | |
131 | See L<openssl(1)/Format Options> for details. | |
fd13f0ee | 132 | |
e8769719 | 133 | =item B<-stream>, B<-indef>, B<-noindef> |
76b46e77 | 134 | |
c4de074e | 135 | The B<-stream> and B<-indef> options are equivalent and enable streaming I/O |
76b46e77 DSH |
136 | for encoding operations. This permits single pass processing of data without |
137 | the need to hold the entire contents in memory, potentially supporting very | |
138 | large files. Streaming is automatically set for S/MIME signing with detached | |
139 | data if the output format is B<SMIME> it is currently off by default for all | |
140 | other operations. | |
141 | ||
142 | =item B<-noindef> | |
143 | ||
c4de074e | 144 | Disable streaming I/O where it would produce and indefinite length constructed |
76b46e77 DSH |
145 | encoding. This option currently has no effect. In future streaming will be |
146 | enabled by default on all relevant operations and this option will disable it. | |
147 | ||
e8769719 | 148 | =item B<-content> I<filename> |
fd13f0ee DSH |
149 | |
150 | This specifies a file containing the detached content, this is only | |
151 | useful with the B<-verify> command. This is only usable if the PKCS#7 | |
152 | structure is using the detached signature form where the content is | |
153 | not included. This option will override any content if the input format | |
154 | is S/MIME and it uses the multipart/signed MIME content type. | |
155 | ||
e3775a33 DSH |
156 | =item B<-text> |
157 | ||
c4de074e | 158 | This option adds plain text (text/plain) MIME headers to the supplied |
e3775a33 | 159 | message if encrypting or signing. If decrypting or verifying it strips |
1bc74519 | 160 | off text headers: if the decrypted or verified message is not of MIME |
e3775a33 DSH |
161 | type text/plain then an error occurs. |
162 | ||
e8769719 | 163 | =item B<-md> I<digest> |
d884c5ba | 164 | |
c4de074e | 165 | Digest algorithm to use when signing or resigning. If not present then the |
d884c5ba DSH |
166 | default digest algorithm for the signing key will be used (usually SHA1). |
167 | ||
8dc57d76 | 168 | =item B<-I<cipher>> |
e3775a33 | 169 | |
c4de074e | 170 | The encryption algorithm to use. For example DES (56 bits) - B<-des>, |
e5fa864f | 171 | triple DES (168 bits) - B<-des3>, |
1bc74519 | 172 | EVP_get_cipherbyname() function) can also be used preceded by a dash, for |
35a810bb | 173 | example B<-aes-128-cbc>. See L<openssl-enc(1)> for list of ciphers |
e5fa864f | 174 | supported by your version of OpenSSL. |
d884c5ba | 175 | |
6f719f06 | 176 | If not specified triple DES is used. Only used with B<-encrypt>. |
e3775a33 DSH |
177 | |
178 | =item B<-nointern> | |
179 | ||
c4de074e | 180 | When verifying a message normally certificates (if any) included in |
e3775a33 DSH |
181 | the message are searched for the signing certificate. With this option |
182 | only the certificates specified in the B<-certfile> option are used. | |
183 | The supplied certificates can still be used as untrusted CAs however. | |
184 | ||
185 | =item B<-noverify> | |
186 | ||
c4de074e | 187 | Do not verify the signers certificate of a signed message. |
e3775a33 DSH |
188 | |
189 | =item B<-nochain> | |
190 | ||
65718c51 | 191 | Do not do chain verification of signers certificates; that is, do not |
e3775a33 DSH |
192 | use the certificates in the signed message as untrusted CAs. |
193 | ||
194 | =item B<-nosigs> | |
195 | ||
c4de074e | 196 | Don't try to verify the signatures on the message. |
e3775a33 DSH |
197 | |
198 | =item B<-nocerts> | |
199 | ||
c4de074e | 200 | When signing a message the signer's certificate is normally included |
e3775a33 DSH |
201 | with this option it is excluded. This will reduce the size of the |
202 | signed message but the verifier must have a copy of the signers certificate | |
203 | available locally (passed using the B<-certfile> option for example). | |
204 | ||
205 | =item B<-noattr> | |
206 | ||
c4de074e | 207 | Normally when a message is signed a set of attributes are included which |
e3775a33 DSH |
208 | include the signing time and supported symmetric algorithms. With this |
209 | option they are not included. | |
210 | ||
65718c51 RS |
211 | =item B<-nodetach> |
212 | ||
213 | When signing a message use opaque signing. This form is more resistant | |
214 | to translation by mail relays but it cannot be read by mail agents that | |
215 | do not support S/MIME. Without this option cleartext signing with | |
216 | the MIME type multipart/signed is used. | |
217 | ||
218 | =item B<-nosmimecap> | |
219 | ||
220 | When signing a message, do not include the B<SMIMECapabilities> attribute. | |
221 | ||
e3775a33 DSH |
222 | =item B<-binary> |
223 | ||
c4de074e | 224 | Normally the input message is converted to "canonical" format which is |
3fc9635e DSH |
225 | effectively using CR and LF as end of line: as required by the S/MIME |
226 | specification. When this option is present no translation occurs. This | |
227 | is useful when handling binary data which may not be in MIME format. | |
e3775a33 | 228 | |
2197494d DSH |
229 | =item B<-crlfeol> |
230 | ||
c4de074e | 231 | Normally the output file uses a single B<LF> as end of line. When this |
2197494d DSH |
232 | option is present B<CRLF> is used instead. |
233 | ||
e8769719 | 234 | =item B<-certfile> I<file> |
e3775a33 | 235 | |
c4de074e | 236 | Allows additional certificates to be specified. When signing these will |
e3775a33 DSH |
237 | be included with the message. When verifying these will be searched for |
238 | the signers certificates. The certificates should be in PEM format. | |
239 | ||
e8769719 | 240 | =item B<-signer> I<file> |
e3775a33 | 241 | |
c4de074e | 242 | A signing certificate when signing or resigning a message, this option can be |
d884c5ba DSH |
243 | used multiple times if more than one signer is required. If a message is being |
244 | verified then the signers certificates will be written to this file if the | |
245 | verification was successful. | |
e3775a33 | 246 | |
65718c51 RS |
247 | =item B<-nocerts> |
248 | ||
249 | Don't include signers certificate when signing. | |
250 | ||
251 | =item B<-noattr> | |
252 | ||
253 | Don't include any signed attributes when signing. | |
254 | ||
e8769719 | 255 | =item B<-recip> I<file> |
e3775a33 | 256 | |
c4de074e | 257 | The recipients certificate when decrypting a message. This certificate |
e3775a33 DSH |
258 | must match one of the recipients of the message or an error occurs. |
259 | ||
e8769719 | 260 | =item B<-inkey> I<file_or_id> |
e3775a33 | 261 | |
c4de074e | 262 | The private key to use when signing or decrypting. This must match the |
e3775a33 DSH |
263 | corresponding certificate. If this option is not specified then the |
264 | private key must be included in the certificate file specified with | |
d884c5ba DSH |
265 | the B<-recip> or B<-signer> file. When signing this option can be used |
266 | multiple times to specify successive keys. | |
48b53522 RS |
267 | If no engine is used, the argument is taken as a file; if an engine is |
268 | specified, the argument is given to the engine as a key identifier. | |
e3775a33 | 269 | |
e8769719 | 270 | =item B<-passin> I<arg> |
84b65340 | 271 | |
2f0ea936 | 272 | The private key password source. For more information about the format of I<arg> |
3a4e43de | 273 | see L<openssl(1)/Pass Phrase Options>. |
84b65340 | 274 | |
8dc57d76 | 275 | =item B<-to>, B<-from>, B<-subject> |
e3775a33 | 276 | |
c4de074e | 277 | The relevant mail headers. These are included outside the signed |
e3775a33 DSH |
278 | portion of a message so they may be included manually. If signing |
279 | then many S/MIME mail clients check the signers certificate's email | |
280 | address matches that specified in the From: address. | |
281 | ||
21d08b9e | 282 | {- $OpenSSL::safe::opt_v_item -} |
e5fa864f | 283 | |
21d08b9e | 284 | Any verification errors cause the command to exit. |
e5fa864f | 285 | |
9fcb9702 RS |
286 | {- $OpenSSL::safe::opt_trust_item -} |
287 | ||
65718c51 RS |
288 | {- $OpenSSL::safe::opt_engine_item -} |
289 | ||
9fcb9702 RS |
290 | {- $OpenSSL::safe::opt_r_item -} |
291 | ||
6bd4e3f2 P |
292 | {- $OpenSSL::safe::opt_provider_item -} |
293 | ||
b1c0cc24 RL |
294 | =item I<cert.pem> ... |
295 | ||
296 | One or more certificates of message recipients, used when encrypting | |
297 | a message. | |
298 | ||
e3775a33 DSH |
299 | =back |
300 | ||
301 | =head1 NOTES | |
302 | ||
303 | The MIME message must be sent without any blank lines between the | |
304 | headers and the output. Some mail programs will automatically add | |
305 | a blank line. Piping the mail directly to sendmail is one way to | |
306 | achieve the correct format. | |
307 | ||
3fc9635e | 308 | The supplied message to be signed or encrypted must include the |
60250017 | 309 | necessary MIME headers or many S/MIME clients won't display it |
3fc9635e DSH |
310 | properly (if at all). You can use the B<-text> option to automatically |
311 | add plain text headers. | |
312 | ||
e3775a33 DSH |
313 | A "signed and encrypted" message is one where a signed message is |
314 | then encrypted. This can be produced by encrypting an already signed | |
3fc9635e | 315 | message: see the examples section. |
e3775a33 DSH |
316 | |
317 | This version of the program only allows one signer per message but it | |
318 | will verify multiple signers on received messages. Some S/MIME clients | |
19d2bb57 | 319 | choke if a message contains multiple signers. It is possible to sign |
e3775a33 DSH |
320 | messages "in parallel" by signing an already signed message. |
321 | ||
3fc9635e DSH |
322 | The options B<-encrypt> and B<-decrypt> reflect common usage in S/MIME |
323 | clients. Strictly speaking these process PKCS#7 enveloped data: PKCS#7 | |
324 | encrypted data is used for other purposes. | |
325 | ||
d884c5ba DSH |
326 | The B<-resign> option uses an existing message digest when adding a new |
327 | signer. This means that attributes must be present in at least one existing | |
328 | signer using the same message digest or this operation will fail. | |
329 | ||
e4ef2e25 | 330 | The B<-stream> and B<-indef> options enable streaming I/O support. |
76b46e77 DSH |
331 | As a result the encoding is BER using indefinite length constructed encoding |
332 | and no longer DER. Streaming is supported for the B<-encrypt> operation and the | |
333 | B<-sign> operation if the content is not detached. | |
334 | ||
335 | Streaming is always used for the B<-sign> operation with detached data but | |
336 | since the content is no longer part of the PKCS#7 structure the encoding | |
337 | remains DER. | |
338 | ||
e3775a33 DSH |
339 | =head1 EXIT CODES |
340 | ||
341 | =over 4 | |
342 | ||
c8919dde | 343 | =item Z<>0 |
e3775a33 | 344 | |
c4de074e | 345 | The operation was completely successfully. |
e3775a33 | 346 | |
c8919dde | 347 | =item Z<>1 |
e3775a33 | 348 | |
c4de074e | 349 | An error occurred parsing the command options. |
e3775a33 | 350 | |
c8919dde | 351 | =item Z<>2 |
e3775a33 | 352 | |
c4de074e | 353 | One of the input files could not be read. |
e3775a33 | 354 | |
c8919dde | 355 | =item Z<>3 |
e3775a33 | 356 | |
c4de074e | 357 | An error occurred creating the PKCS#7 file or when reading the MIME |
e3775a33 DSH |
358 | message. |
359 | ||
c8919dde | 360 | =item Z<>4 |
e3775a33 | 361 | |
c4de074e | 362 | An error occurred decrypting or verifying the message. |
e3775a33 | 363 | |
c8919dde | 364 | =item Z<>5 |
e3775a33 | 365 | |
c4de074e | 366 | The message was verified correctly but an error occurred writing out |
e3775a33 DSH |
367 | the signers certificates. |
368 | ||
369 | =back | |
370 | ||
371 | =head1 EXAMPLES | |
372 | ||
3fc9635e DSH |
373 | Create a cleartext signed message: |
374 | ||
1675f6eb | 375 | openssl smime -sign -in message.txt -text -out mail.msg \ |
1bc74519 | 376 | -signer mycert.pem |
3fc9635e | 377 | |
0d638dc1 | 378 | Create an opaque signed message: |
3fc9635e | 379 | |
1675f6eb | 380 | openssl smime -sign -in message.txt -text -out mail.msg -nodetach \ |
1bc74519 | 381 | -signer mycert.pem |
3fc9635e DSH |
382 | |
383 | Create a signed message, include some additional certificates and | |
384 | read the private key from another file: | |
385 | ||
1675f6eb | 386 | openssl smime -sign -in in.txt -text -out mail.msg \ |
1bc74519 | 387 | -signer mycert.pem -inkey mykey.pem -certfile mycerts.pem |
3fc9635e | 388 | |
d884c5ba DSH |
389 | Create a signed message with two signers: |
390 | ||
391 | openssl smime -sign -in message.txt -text -out mail.msg \ | |
1bc74519 | 392 | -signer mycert.pem -signer othercert.pem |
d884c5ba | 393 | |
3fc9635e DSH |
394 | Send a signed message under Unix directly to sendmail, including headers: |
395 | ||
1675f6eb | 396 | openssl smime -sign -in in.txt -text -signer mycert.pem \ |
1bc74519 RS |
397 | -from steve@openssl.org -to someone@somewhere \ |
398 | -subject "Signed message" | sendmail someone@somewhere | |
3fc9635e DSH |
399 | |
400 | Verify a message and extract the signer's certificate if successful: | |
401 | ||
402 | openssl smime -verify -in mail.msg -signer user.pem -out signedtext.txt | |
403 | ||
404 | Send encrypted mail using triple DES: | |
405 | ||
1675f6eb | 406 | openssl smime -encrypt -in in.txt -from steve@openssl.org \ |
1bc74519 RS |
407 | -to someone@somewhere -subject "Encrypted message" \ |
408 | -des3 user.pem -out mail.msg | |
3fc9635e DSH |
409 | |
410 | Sign and encrypt mail: | |
411 | ||
1675f6eb | 412 | openssl smime -sign -in ml.txt -signer my.pem -text \ |
1bc74519 RS |
413 | | openssl smime -encrypt -out mail.msg \ |
414 | -from steve@openssl.org -to someone@somewhere \ | |
415 | -subject "Signed and Encrypted message" -des3 user.pem | |
3fc9635e | 416 | |
d884c5ba DSH |
417 | Note: the encryption command does not include the B<-text> option because the |
418 | message being encrypted already has MIME headers. | |
3fc9635e DSH |
419 | |
420 | Decrypt mail: | |
421 | ||
422 | openssl smime -decrypt -in mail.msg -recip mycert.pem -inkey key.pem | |
423 | ||
fd13f0ee DSH |
424 | The output from Netscape form signing is a PKCS#7 structure with the |
425 | detached signature format. You can use this program to verify the | |
426 | signature by line wrapping the base64 encoded structure and surrounding | |
427 | it with: | |
428 | ||
a8c12555 DSH |
429 | -----BEGIN PKCS7----- |
430 | -----END PKCS7----- | |
fd13f0ee | 431 | |
1bc74519 | 432 | and using the command: |
fd13f0ee DSH |
433 | |
434 | openssl smime -verify -inform PEM -in signature.pem -content content.txt | |
435 | ||
0d638dc1 | 436 | Alternatively you can base64 decode the signature and use: |
fd13f0ee DSH |
437 | |
438 | openssl smime -verify -inform DER -in signature.der -content content.txt | |
439 | ||
f3dea9a5 BM |
440 | Create an encrypted message using 128 bit Camellia: |
441 | ||
442 | openssl smime -encrypt -in plain.txt -camellia128 -out mail.msg cert.pem | |
443 | ||
d884c5ba DSH |
444 | Add a signer to an existing message: |
445 | ||
446 | openssl smime -resign -in mail.msg -signer newsign.pem -out mail2.msg | |
447 | ||
3fc9635e DSH |
448 | =head1 BUGS |
449 | ||
d884c5ba DSH |
450 | The MIME parser isn't very clever: it seems to handle most messages that I've |
451 | thrown at it but it may choke on others. | |
3fc9635e | 452 | |
d884c5ba DSH |
453 | The code currently will only write out the signer's certificate to a file: if |
454 | the signer has a separate encryption certificate this must be manually | |
455 | extracted. There should be some heuristic that determines the correct | |
456 | encryption certificate. | |
3fc9635e | 457 | |
d884c5ba DSH |
458 | Ideally a database should be maintained of a certificates for each email |
459 | address. | |
3fc9635e DSH |
460 | |
461 | The code doesn't currently take note of the permitted symmetric encryption | |
7e0de9e8 | 462 | algorithms as supplied in the SMIMECapabilities signed attribute. This means the |
3fc9635e DSH |
463 | user has to manually include the correct encryption algorithm. It should store |
464 | the list of permitted ciphers in a database and only use those. | |
465 | ||
466 | No revocation checking is done on the signer's certificate. | |
467 | ||
468 | The current code can only handle S/MIME v2 messages, the more complex S/MIME v3 | |
469 | structures may cause parsing errors. | |
e3775a33 | 470 | |
fd3397fc RL |
471 | =head1 SEE ALSO |
472 | ||
473 | L<ossl_store-file(7)> | |
474 | ||
d884c5ba DSH |
475 | =head1 HISTORY |
476 | ||
477 | The use of multiple B<-signer> options and the B<-resign> command were first | |
fb552ac6 | 478 | added in OpenSSL 1.0.0 |
d884c5ba | 479 | |
fc5ecadd | 480 | The -no_alt_chains option was added in OpenSSL 1.1.0. |
d884c5ba | 481 | |
e2f92610 RS |
482 | =head1 COPYRIGHT |
483 | ||
33388b44 | 484 | Copyright 2000-2020 The OpenSSL Project Authors. All Rights Reserved. |
e2f92610 | 485 | |
449040b4 | 486 | Licensed under the Apache License 2.0 (the "License"). You may not use |
e2f92610 RS |
487 | this file except in compliance with the License. You can obtain a copy |
488 | in the file LICENSE in the source distribution or at | |
489 | L<https://www.openssl.org/source/license.html>. | |
490 | ||
491 | =cut |