cb98944ef575305d3e79032e84d5f09668f9c3d8
[openssl.git] / crypto / asn1 / asn_mime.c
1 /* asn_mime.c */
2 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
3  * project.
4  */
5 /* ====================================================================
6  * Copyright (c) 1999-2008 The OpenSSL Project.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer. 
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in
17  *    the documentation and/or other materials provided with the
18  *    distribution.
19  *
20  * 3. All advertising materials mentioning features or use of this
21  *    software must display the following acknowledgment:
22  *    "This product includes software developed by the OpenSSL Project
23  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
24  *
25  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26  *    endorse or promote products derived from this software without
27  *    prior written permission. For written permission, please contact
28  *    licensing@OpenSSL.org.
29  *
30  * 5. Products derived from this software may not be called "OpenSSL"
31  *    nor may "OpenSSL" appear in their names without prior written
32  *    permission of the OpenSSL Project.
33  *
34  * 6. Redistributions of any form whatsoever must retain the following
35  *    acknowledgment:
36  *    "This product includes software developed by the OpenSSL Project
37  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38  *
39  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
43  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50  * OF THE POSSIBILITY OF SUCH DAMAGE.
51  * ====================================================================
52  *
53  */
54
55 #include <stdio.h>
56 #include <ctype.h>
57 #include "cryptlib.h"
58 #include <openssl/rand.h>
59 #include <openssl/x509.h>
60 #include <openssl/asn1.h>
61 #include <openssl/asn1t.h>
62 #include "asn1_locl.h"
63
64 /* Generalised MIME like utilities for streaming ASN1. Although many
65  * have a PKCS7/CMS like flavour others are more general purpose.
66  */
67
68 /* MIME format structures
69  * Note that all are translated to lower case apart from
70  * parameter values. Quotes are stripped off
71  */
72
73 typedef struct {
74 char *param_name;                       /* Param name e.g. "micalg" */
75 char *param_value;                      /* Param value e.g. "sha1" */
76 } MIME_PARAM;
77
78 DECLARE_STACK_OF(MIME_PARAM)
79 IMPLEMENT_STACK_OF(MIME_PARAM)
80
81 typedef struct {
82 char *name;                             /* Name of line e.g. "content-type" */
83 char *value;                            /* Value of line e.g. "text/plain" */
84 STACK_OF(MIME_PARAM) *params;           /* Zero or more parameters */
85 } MIME_HEADER;
86
87 DECLARE_STACK_OF(MIME_HEADER)
88 IMPLEMENT_STACK_OF(MIME_HEADER)
89
90 static int asn1_output_data(BIO *out, BIO *data, ASN1_VALUE *val, int flags,
91                                         const ASN1_ITEM *it);
92 static char * strip_ends(char *name);
93 static char * strip_start(char *name);
94 static char * strip_end(char *name);
95 static MIME_HEADER *mime_hdr_new(char *name, char *value);
96 static int mime_hdr_addparam(MIME_HEADER *mhdr, char *name, char *value);
97 static STACK_OF(MIME_HEADER) *mime_parse_hdr(BIO *bio);
98 static int mime_hdr_cmp(const MIME_HEADER * const *a,
99                         const MIME_HEADER * const *b);
100 static int mime_param_cmp(const MIME_PARAM * const *a,
101                         const MIME_PARAM * const *b);
102 static void mime_param_free(MIME_PARAM *param);
103 static int mime_bound_check(char *line, int linelen, char *bound, int blen);
104 static int multi_split(BIO *bio, char *bound, STACK_OF(BIO) **ret);
105 static int strip_eol(char *linebuf, int *plen, int flags);
106 static MIME_HEADER *mime_hdr_find(STACK_OF(MIME_HEADER) *hdrs, char *name);
107 static MIME_PARAM *mime_param_find(MIME_HEADER *hdr, char *name);
108 static void mime_hdr_free(MIME_HEADER *hdr);
109
110 #define MAX_SMLEN 1024
111 #define mime_debug(x) /* x */
112
113 /* Output an ASN1 structure in BER format streaming if necessary */
114
115 int i2d_ASN1_bio_stream(BIO *out, ASN1_VALUE *val, BIO *in, int flags,
116                                 const ASN1_ITEM *it)
117         {
118         /* If streaming create stream BIO and copy all content through it */
119         if (flags & SMIME_STREAM)
120                 {
121                 BIO *bio, *tbio;
122                 bio = BIO_new_NDEF(out, val, it);
123                 if (!bio)
124                         {
125                         ASN1err(ASN1_F_I2D_ASN1_BIO_STREAM,ERR_R_MALLOC_FAILURE);
126                         return 0;
127                         }
128                 SMIME_crlf_copy(in, bio, flags);
129                 (void)BIO_flush(bio);
130                 /* Free up successive BIOs until we hit the old output BIO */
131                 do
132                         {
133                         tbio = BIO_pop(bio);
134                         BIO_free(bio);
135                         bio = tbio;
136                         } while (bio != out);
137                 }
138         /* else just write out ASN1 structure which will have all content
139          * stored internally
140          */
141         else
142                 ASN1_item_i2d_bio(it, out, val);
143         return 1;
144         }
145
146 /* Base 64 read and write of ASN1 structure */
147
148 static int B64_write_ASN1(BIO *out, ASN1_VALUE *val, BIO *in, int flags,
149                                 const ASN1_ITEM *it)
150         {
151         BIO *b64;
152         int r;
153         b64 = BIO_new(BIO_f_base64());
154         if(!b64)
155                 {
156                 ASN1err(ASN1_F_B64_WRITE_ASN1,ERR_R_MALLOC_FAILURE);
157                 return 0;
158                 }
159         /* prepend the b64 BIO so all data is base64 encoded.
160          */
161         out = BIO_push(b64, out);
162         r = i2d_ASN1_bio_stream(out, val, in, flags, it);
163         (void)BIO_flush(out);
164         BIO_pop(out);
165         BIO_free(b64);
166         return r;
167         }
168
169 /* Streaming ASN1 PEM write */
170
171 int PEM_write_bio_ASN1_stream(BIO *out, ASN1_VALUE *val, BIO *in, int flags,
172                                 const char *hdr,
173                                 const ASN1_ITEM *it)
174         {
175         int r;
176         BIO_printf(out, "-----BEGIN %s-----\n", hdr);
177         r = B64_write_ASN1(out, val, in, flags, it);
178         BIO_printf(out, "-----END %s-----\n", hdr);
179         return r;
180         }
181
182 static ASN1_VALUE *b64_read_asn1(BIO *bio, const ASN1_ITEM *it)
183 {
184         BIO *b64;
185         ASN1_VALUE *val;
186         if(!(b64 = BIO_new(BIO_f_base64()))) {
187                 ASN1err(ASN1_F_B64_READ_ASN1,ERR_R_MALLOC_FAILURE);
188                 return 0;
189         }
190         bio = BIO_push(b64, bio);
191         val = ASN1_item_d2i_bio(it, bio, NULL);
192         if(!val)
193                 ASN1err(ASN1_F_B64_READ_ASN1,ASN1_R_DECODE_ERROR);
194         (void)BIO_flush(bio);
195         bio = BIO_pop(bio);
196         BIO_free(b64);
197         return val;
198 }
199
200 /* Generate the MIME "micalg" parameter from RFC3851, RFC4490 */
201
202 static int asn1_write_micalg(BIO *out, STACK_OF(X509_ALGOR) *mdalgs)
203         {
204         const EVP_MD *md;
205         int i, have_unknown = 0, write_comma, ret = 0, md_nid;
206         have_unknown = 0;
207         write_comma = 0;
208         for (i = 0; i < sk_X509_ALGOR_num(mdalgs); i++)
209                 {
210                 if (write_comma)
211                         BIO_write(out, ",", 1);
212                 write_comma = 1;
213                 md_nid = OBJ_obj2nid(sk_X509_ALGOR_value(mdalgs, i)->algorithm);
214                 md = EVP_get_digestbynid(md_nid);
215                 if (md && md->md_ctrl)
216                         {
217                         int rv;
218                         char *micstr;
219                         rv = md->md_ctrl(NULL, EVP_MD_CTRL_MICALG, 0, &micstr);
220                         if (rv > 0)
221                                 {
222                                 BIO_puts(out, micstr);
223                                 OPENSSL_free(micstr);
224                                 continue;
225                                 }
226                         if (rv != -2)
227                                 goto err;
228                         }
229                 switch(md_nid)
230                         {
231                         case NID_sha1:
232                         BIO_puts(out, "sha1");
233                         break;
234
235                         case NID_md5:
236                         BIO_puts(out, "md5");
237                         break;
238
239                         case NID_sha256:
240                         BIO_puts(out, "sha-256");
241                         break;
242
243                         case NID_sha384:
244                         BIO_puts(out, "sha-384");
245                         break;
246
247                         case NID_sha512:
248                         BIO_puts(out, "sha-512");
249                         break;
250
251                         case NID_id_GostR3411_94:
252                         BIO_puts(out, "gostr3411-94");
253                                 goto err;
254                         break;
255
256                         default:
257                         if (have_unknown)
258                                 write_comma = 0;
259                         else
260                                 {
261                                 BIO_puts(out, "unknown");
262                                 have_unknown = 1;
263                                 }
264                         break;
265
266                         }
267                 }
268
269         ret = 1;
270         err:
271
272         return ret;
273
274         }
275
276 /* SMIME sender */
277
278 int SMIME_write_ASN1(BIO *bio, ASN1_VALUE *val, BIO *data, int flags,
279                                 int ctype_nid, int econt_nid,
280                                 STACK_OF(X509_ALGOR) *mdalgs,
281                                 const ASN1_ITEM *it)
282 {
283         char bound[33], c;
284         int i;
285         const char *mime_prefix, *mime_eol, *cname = "smime.p7m";
286         const char *msg_type=NULL;
287         if (flags & SMIME_OLDMIME)
288                 mime_prefix = "application/x-pkcs7-";
289         else
290                 mime_prefix = "application/pkcs7-";
291
292         if (flags & SMIME_CRLFEOL)
293                 mime_eol = "\r\n";
294         else
295                 mime_eol = "\n";
296         if((flags & SMIME_DETACHED) && data) {
297         /* We want multipart/signed */
298                 /* Generate a random boundary */
299                 RAND_pseudo_bytes((unsigned char *)bound, 32);
300                 for(i = 0; i < 32; i++) {
301                         c = bound[i] & 0xf;
302                         if(c < 10) c += '0';
303                         else c += 'A' - 10;
304                         bound[i] = c;
305                 }
306                 bound[32] = 0;
307                 BIO_printf(bio, "MIME-Version: 1.0%s", mime_eol);
308                 BIO_printf(bio, "Content-Type: multipart/signed;");
309                 BIO_printf(bio, " protocol=\"%ssignature\";", mime_prefix);
310                 BIO_puts(bio, " micalg=\"");
311                 asn1_write_micalg(bio, mdalgs);
312                 BIO_printf(bio, "\"; boundary=\"----%s\"%s%s",
313                                                 bound, mime_eol, mime_eol);
314                 BIO_printf(bio, "This is an S/MIME signed message%s%s",
315                                                 mime_eol, mime_eol);
316                 /* Now write out the first part */
317                 BIO_printf(bio, "------%s%s", bound, mime_eol);
318                 if (!asn1_output_data(bio, data, val, flags, it))
319                         return 0;
320                 BIO_printf(bio, "%s------%s%s", mime_eol, bound, mime_eol);
321
322                 /* Headers for signature */
323
324                 BIO_printf(bio, "Content-Type: %ssignature;", mime_prefix); 
325                 BIO_printf(bio, " name=\"smime.p7s\"%s", mime_eol);
326                 BIO_printf(bio, "Content-Transfer-Encoding: base64%s",
327                                                                 mime_eol);
328                 BIO_printf(bio, "Content-Disposition: attachment;");
329                 BIO_printf(bio, " filename=\"smime.p7s\"%s%s",
330                                                         mime_eol, mime_eol);
331                 B64_write_ASN1(bio, val, NULL, 0, it);
332                 BIO_printf(bio,"%s------%s--%s%s", mime_eol, bound,
333                                                         mime_eol, mime_eol);
334                 return 1;
335         }
336
337         /* Determine smime-type header */
338
339         if (ctype_nid == NID_pkcs7_enveloped)
340                 msg_type = "enveloped-data";
341         else if (ctype_nid == NID_pkcs7_signed)
342                 {
343                 if (econt_nid == NID_id_smime_ct_receipt)
344                         msg_type = "signed-receipt";
345                 else if (sk_X509_ALGOR_num(mdalgs) >= 0)
346                         msg_type = "signed-data";
347                 else
348                         msg_type = "certs-only";
349                 }
350         else if (ctype_nid == NID_id_smime_ct_compressedData)
351                 {
352                 msg_type = "compressed-data";
353                 cname = "smime.p7z";
354                 }
355         /* MIME headers */
356         BIO_printf(bio, "MIME-Version: 1.0%s", mime_eol);
357         BIO_printf(bio, "Content-Disposition: attachment;");
358         BIO_printf(bio, " filename=\"%s\"%s", cname, mime_eol);
359         BIO_printf(bio, "Content-Type: %smime;", mime_prefix);
360         if (msg_type)
361                 BIO_printf(bio, " smime-type=%s;", msg_type);
362         BIO_printf(bio, " name=\"%s\"%s", cname, mime_eol);
363         BIO_printf(bio, "Content-Transfer-Encoding: base64%s%s",
364                                                 mime_eol, mime_eol);
365         if (!B64_write_ASN1(bio, val, data, flags, it))
366                 return 0;
367         BIO_printf(bio, "%s", mime_eol);
368         return 1;
369 }
370
371 /* Handle output of ASN1 data */
372
373
374 static int asn1_output_data(BIO *out, BIO *data, ASN1_VALUE *val, int flags,
375                                         const ASN1_ITEM *it)
376         {
377         BIO *tmpbio;
378         const ASN1_AUX *aux = it->funcs;
379         ASN1_STREAM_ARG sarg;
380         int rv = 1;
381
382         /* If data is not deteched or resigning then the output BIO is
383          * already set up to finalise when it is written through.
384          */
385         if (!(flags & SMIME_DETACHED) || (flags & PKCS7_REUSE_DIGEST))
386                 {
387                 SMIME_crlf_copy(data, out, flags);
388                 return 1;
389                 }
390
391         if (!aux || !aux->asn1_cb)
392                 {
393                 ASN1err(ASN1_F_ASN1_OUTPUT_DATA,
394                                         ASN1_R_STREAMING_NOT_SUPPORTED);
395                 return 0;
396                 }
397
398         sarg.out = out;
399         sarg.ndef_bio = NULL;
400         sarg.boundary = NULL;
401
402         /* Let ASN1 code prepend any needed BIOs */
403
404         if (aux->asn1_cb(ASN1_OP_DETACHED_PRE, &val, it, &sarg) <= 0)
405                 return 0;
406
407         /* Copy data across, passing through filter BIOs for processing */
408         SMIME_crlf_copy(data, sarg.ndef_bio, flags);
409
410         /* Finalize structure */
411         if (aux->asn1_cb(ASN1_OP_DETACHED_POST, &val, it, &sarg) <= 0)
412                 rv = 0;
413
414         /* Now remove any digests prepended to the BIO */
415
416         while (sarg.ndef_bio != out)
417                 {
418                 tmpbio = BIO_pop(sarg.ndef_bio);
419                 BIO_free(sarg.ndef_bio);
420                 sarg.ndef_bio = tmpbio;
421                 }
422
423         return rv;
424
425         }
426
427 /* SMIME reader: handle multipart/signed and opaque signing.
428  * in multipart case the content is placed in a memory BIO
429  * pointed to by "bcont". In opaque this is set to NULL
430  */
431
432 ASN1_VALUE *SMIME_read_ASN1(BIO *bio, BIO **bcont, const ASN1_ITEM *it)
433 {
434         BIO *asnin;
435         STACK_OF(MIME_HEADER) *headers = NULL;
436         STACK_OF(BIO) *parts = NULL;
437         MIME_HEADER *hdr;
438         MIME_PARAM *prm;
439         ASN1_VALUE *val;
440         int ret;
441
442         if(bcont) *bcont = NULL;
443
444         if (!(headers = mime_parse_hdr(bio))) {
445                 ASN1err(ASN1_F_SMIME_READ_ASN1,ASN1_R_MIME_PARSE_ERROR);
446                 return NULL;
447         }
448
449         if(!(hdr = mime_hdr_find(headers, "content-type")) || !hdr->value) {
450                 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
451                 ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_NO_CONTENT_TYPE);
452                 return NULL;
453         }
454
455         /* Handle multipart/signed */
456
457         if(!strcmp(hdr->value, "multipart/signed")) {
458                 /* Split into two parts */
459                 prm = mime_param_find(hdr, "boundary");
460                 if(!prm || !prm->param_value) {
461                         sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
462                         ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_NO_MULTIPART_BOUNDARY);
463                         return NULL;
464                 }
465                 ret = multi_split(bio, prm->param_value, &parts);
466                 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
467                 if(!ret || (sk_BIO_num(parts) != 2) ) {
468                         ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_NO_MULTIPART_BODY_FAILURE);
469                         sk_BIO_pop_free(parts, BIO_vfree);
470                         return NULL;
471                 }
472
473                 /* Parse the signature piece */
474                 asnin = sk_BIO_value(parts, 1);
475
476                 if (!(headers = mime_parse_hdr(asnin))) {
477                         ASN1err(ASN1_F_SMIME_READ_ASN1,ASN1_R_MIME_SIG_PARSE_ERROR);
478                         sk_BIO_pop_free(parts, BIO_vfree);
479                         return NULL;
480                 }
481
482                 /* Get content type */
483
484                 if(!(hdr = mime_hdr_find(headers, "content-type")) ||
485                                                                  !hdr->value) {
486                         sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
487                         ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_NO_SIG_CONTENT_TYPE);
488                         return NULL;
489                 }
490
491                 if(strcmp(hdr->value, "application/x-pkcs7-signature") &&
492                         strcmp(hdr->value, "application/pkcs7-signature")) {
493                         ASN1err(ASN1_F_SMIME_READ_ASN1,ASN1_R_SIG_INVALID_MIME_TYPE);
494                         ERR_add_error_data(2, "type: ", hdr->value);
495                         sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
496                         sk_BIO_pop_free(parts, BIO_vfree);
497                         return NULL;
498                 }
499                 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
500                 /* Read in ASN1 */
501                 if(!(val = b64_read_asn1(asnin, it))) {
502                         ASN1err(ASN1_F_SMIME_READ_ASN1,ASN1_R_ASN1_SIG_PARSE_ERROR);
503                         sk_BIO_pop_free(parts, BIO_vfree);
504                         return NULL;
505                 }
506
507                 if(bcont) {
508                         *bcont = sk_BIO_value(parts, 0);
509                         BIO_free(asnin);
510                         sk_BIO_free(parts);
511                 } else sk_BIO_pop_free(parts, BIO_vfree);
512                 return val;
513         }
514                 
515         /* OK, if not multipart/signed try opaque signature */
516
517         if (strcmp (hdr->value, "application/x-pkcs7-mime") &&
518             strcmp (hdr->value, "application/pkcs7-mime")) {
519                 ASN1err(ASN1_F_SMIME_READ_ASN1,ASN1_R_INVALID_MIME_TYPE);
520                 ERR_add_error_data(2, "type: ", hdr->value);
521                 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
522                 return NULL;
523         }
524
525         sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
526         
527         if(!(val = b64_read_asn1(bio, it))) {
528                 ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_ASN1_PARSE_ERROR);
529                 return NULL;
530         }
531         return val;
532
533 }
534
535 /* Copy text from one BIO to another making the output CRLF at EOL */
536 int SMIME_crlf_copy(BIO *in, BIO *out, int flags)
537 {
538         BIO *bf;
539         char eol;
540         int len;
541         char linebuf[MAX_SMLEN];
542         /* Buffer output so we don't write one line at a time. This is
543          * useful when streaming as we don't end up with one OCTET STRING
544          * per line.
545          */
546         bf = BIO_new(BIO_f_buffer());
547         if (!bf)
548                 return 0;
549         out = BIO_push(bf, out);
550         if(flags & SMIME_BINARY)
551                 {
552                 while((len = BIO_read(in, linebuf, MAX_SMLEN)) > 0)
553                                                 BIO_write(out, linebuf, len);
554                 }
555         else
556                 {
557                 int eolcnt = 0;
558                 if(flags & SMIME_TEXT)
559                         BIO_printf(out, "Content-Type: text/plain\r\n\r\n");
560                 while ((len = BIO_gets(in, linebuf, MAX_SMLEN)) > 0)
561                         {
562                         eol = strip_eol(linebuf, &len, flags);
563                         if (len)
564                                 {
565                                 /* Not EOF: write out all CRLF */
566                                 if (flags & SMIME_ASCIICRLF)
567                                         {
568                                         int i;
569                                         for(i = 0; i < eolcnt; i++)
570                                                 BIO_write(out, "\r\n", 2);
571                                         eolcnt = 0;
572                                         }
573                                 BIO_write(out, linebuf, len);
574                                 if(eol)
575                                         BIO_write(out, "\r\n", 2);
576                                 }
577                         else if (flags & SMIME_ASCIICRLF)
578                                 eolcnt++;       
579                         else if(eol)
580                                 BIO_write(out, "\r\n", 2);
581                         }
582                 }
583         (void)BIO_flush(out);
584         BIO_pop(out);
585         BIO_free(bf);
586         return 1;
587 }
588
589 /* Strip off headers if they are text/plain */
590 int SMIME_text(BIO *in, BIO *out)
591 {
592         char iobuf[4096];
593         int len;
594         STACK_OF(MIME_HEADER) *headers;
595         MIME_HEADER *hdr;
596
597         if (!(headers = mime_parse_hdr(in))) {
598                 ASN1err(ASN1_F_SMIME_TEXT,ASN1_R_MIME_PARSE_ERROR);
599                 return 0;
600         }
601         if(!(hdr = mime_hdr_find(headers, "content-type")) || !hdr->value) {
602                 ASN1err(ASN1_F_SMIME_TEXT,ASN1_R_MIME_NO_CONTENT_TYPE);
603                 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
604                 return 0;
605         }
606         if (strcmp (hdr->value, "text/plain")) {
607                 ASN1err(ASN1_F_SMIME_TEXT,ASN1_R_INVALID_MIME_TYPE);
608                 ERR_add_error_data(2, "type: ", hdr->value);
609                 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
610                 return 0;
611         }
612         sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
613         while ((len = BIO_read(in, iobuf, sizeof(iobuf))) > 0)
614                                                 BIO_write(out, iobuf, len);
615         if (len < 0)
616                 return 0;
617         return 1;
618 }
619
620 /* Split a multipart/XXX message body into component parts: result is
621  * canonical parts in a STACK of bios
622  */
623
624 static int multi_split(BIO *bio, char *bound, STACK_OF(BIO) **ret)
625 {
626         char linebuf[MAX_SMLEN];
627         int len, blen;
628         int eol = 0, next_eol = 0;
629         BIO *bpart = NULL;
630         STACK_OF(BIO) *parts;
631         char state, part, first;
632
633         blen = strlen(bound);
634         part = 0;
635         state = 0;
636         first = 1;
637         parts = sk_BIO_new_null();
638         *ret = parts;
639         while ((len = BIO_gets(bio, linebuf, MAX_SMLEN)) > 0) {
640                 state = mime_bound_check(linebuf, len, bound, blen);
641                 if(state == 1) {
642                         first = 1;
643                         part++;
644                 } else if(state == 2) {
645                         sk_BIO_push(parts, bpart);
646                         return 1;
647                 } else if(part) {
648                         /* Strip CR+LF from linebuf */
649                         next_eol = strip_eol(linebuf, &len, 0);
650                         if(first) {
651                                 first = 0;
652                                 if(bpart) sk_BIO_push(parts, bpart);
653                                 bpart = BIO_new(BIO_s_mem());
654                                 BIO_set_mem_eof_return(bpart, 0);
655                         } else if (eol)
656                                 BIO_write(bpart, "\r\n", 2);
657                         eol = next_eol;
658                         if (len)
659                                 BIO_write(bpart, linebuf, len);
660                 }
661         }
662         return 0;
663 }
664
665 /* This is the big one: parse MIME header lines up to message body */
666
667 #define MIME_INVALID    0
668 #define MIME_START      1
669 #define MIME_TYPE       2
670 #define MIME_NAME       3
671 #define MIME_VALUE      4
672 #define MIME_QUOTE      5
673 #define MIME_COMMENT    6
674
675
676 static STACK_OF(MIME_HEADER) *mime_parse_hdr(BIO *bio)
677 {
678         char *p, *q, c;
679         char *ntmp;
680         char linebuf[MAX_SMLEN];
681         MIME_HEADER *mhdr = NULL;
682         STACK_OF(MIME_HEADER) *headers;
683         int len, state, save_state = 0;
684
685         headers = sk_MIME_HEADER_new(mime_hdr_cmp);
686         if (!headers)
687                 return NULL;
688         while ((len = BIO_gets(bio, linebuf, MAX_SMLEN)) > 0) {
689         /* If whitespace at line start then continuation line */
690         if(mhdr && isspace((unsigned char)linebuf[0])) state = MIME_NAME;
691         else state = MIME_START;
692         ntmp = NULL;
693         /* Go through all characters */
694         for(p = linebuf, q = linebuf; (c = *p) && (c!='\r') && (c!='\n'); p++) {
695
696         /* State machine to handle MIME headers
697          * if this looks horrible that's because it *is*
698          */
699
700                 switch(state) {
701                         case MIME_START:
702                         if(c == ':') {
703                                 state = MIME_TYPE;
704                                 *p = 0;
705                                 ntmp = strip_ends(q);
706                                 q = p + 1;
707                         }
708                         break;
709
710                         case MIME_TYPE:
711                         if(c == ';') {
712                                 mime_debug("Found End Value\n");
713                                 *p = 0;
714                                 mhdr = mime_hdr_new(ntmp, strip_ends(q));
715                                 sk_MIME_HEADER_push(headers, mhdr);
716                                 ntmp = NULL;
717                                 q = p + 1;
718                                 state = MIME_NAME;
719                         } else if(c == '(') {
720                                 save_state = state;
721                                 state = MIME_COMMENT;
722                         }
723                         break;
724
725                         case MIME_COMMENT:
726                         if(c == ')') {
727                                 state = save_state;
728                         }
729                         break;
730
731                         case MIME_NAME:
732                         if(c == '=') {
733                                 state = MIME_VALUE;
734                                 *p = 0;
735                                 ntmp = strip_ends(q);
736                                 q = p + 1;
737                         }
738                         break ;
739
740                         case MIME_VALUE:
741                         if(c == ';') {
742                                 state = MIME_NAME;
743                                 *p = 0;
744                                 mime_hdr_addparam(mhdr, ntmp, strip_ends(q));
745                                 ntmp = NULL;
746                                 q = p + 1;
747                         } else if (c == '"') {
748                                 mime_debug("Found Quote\n");
749                                 state = MIME_QUOTE;
750                         } else if(c == '(') {
751                                 save_state = state;
752                                 state = MIME_COMMENT;
753                         }
754                         break;
755
756                         case MIME_QUOTE:
757                         if(c == '"') {
758                                 mime_debug("Found Match Quote\n");
759                                 state = MIME_VALUE;
760                         }
761                         break;
762                 }
763         }
764
765         if(state == MIME_TYPE) {
766                 mhdr = mime_hdr_new(ntmp, strip_ends(q));
767                 sk_MIME_HEADER_push(headers, mhdr);
768         } else if(state == MIME_VALUE)
769                          mime_hdr_addparam(mhdr, ntmp, strip_ends(q));
770         if(p == linebuf) break; /* Blank line means end of headers */
771 }
772
773 return headers;
774
775 }
776
777 static char *strip_ends(char *name)
778 {
779         return strip_end(strip_start(name));
780 }
781
782 /* Strip a parameter of whitespace from start of param */
783 static char *strip_start(char *name)
784 {
785         char *p, c;
786         /* Look for first non white space or quote */
787         for(p = name; (c = *p) ;p++) {
788                 if(c == '"') {
789                         /* Next char is start of string if non null */
790                         if(p[1]) return p + 1;
791                         /* Else null string */
792                         return NULL;
793                 }
794                 if(!isspace((unsigned char)c)) return p;
795         }
796         return NULL;
797 }
798
799 /* As above but strip from end of string : maybe should handle brackets? */
800 static char *strip_end(char *name)
801 {
802         char *p, c;
803         if(!name) return NULL;
804         /* Look for first non white space or quote */
805         for(p = name + strlen(name) - 1; p >= name ;p--) {
806                 c = *p;
807                 if(c == '"') {
808                         if(p - 1 == name) return NULL;
809                         *p = 0;
810                         return name;
811                 }
812                 if(isspace((unsigned char)c)) *p = 0;   
813                 else return name;
814         }
815         return NULL;
816 }
817
818 static MIME_HEADER *mime_hdr_new(char *name, char *value)
819 {
820         MIME_HEADER *mhdr = NULL;
821         char *tmpname = NULL, *tmpval = NULL, *p;
822         int c;
823         if(name) {
824                 if(!(tmpname = BUF_strdup(name))) return NULL;
825                 for(p = tmpname ; *p; p++) {
826                         c = (unsigned char)*p;
827                         if(isupper(c)) {
828                                 c = tolower(c);
829                                 *p = c;
830                         }
831                 }
832         }
833         if(value) {
834                 if(!(tmpval = BUF_strdup(value)))
835                         goto err;
836                 for(p = tmpval ; *p; p++) {
837                         c = (unsigned char)*p;
838                         if(isupper(c)) {
839                                 c = tolower(c);
840                                 *p = c;
841                         }
842                 }
843         }
844         mhdr = (MIME_HEADER *) OPENSSL_malloc(sizeof(MIME_HEADER));
845         if(!mhdr) goto err;
846         mhdr->name = tmpname;
847         mhdr->value = tmpval;
848         if(!(mhdr->params = sk_MIME_PARAM_new(mime_param_cmp)))
849                 goto err;
850         return mhdr;
851
852         err:
853         if (tmpname != NULL)
854                 OPENSSL_free(tmpname);
855         if (tmpval != NULL)
856                 OPENSSL_free(tmpval);
857         if (mhdr != NULL)
858                 OPENSSL_free(mhdr);
859         return NULL;
860 }
861                 
862 static int mime_hdr_addparam(MIME_HEADER *mhdr, char *name, char *value)
863 {
864         char *tmpname, *tmpval, *p;
865         int c;
866         MIME_PARAM *mparam;
867         if(name) {
868                 tmpname = BUF_strdup(name);
869                 if(!tmpname) return 0;
870                 for(p = tmpname ; *p; p++) {
871                         c = (unsigned char)*p;
872                         if(isupper(c)) {
873                                 c = tolower(c);
874                                 *p = c;
875                         }
876                 }
877         } else tmpname = NULL;
878         if(value) {
879                 tmpval = BUF_strdup(value);
880                 if(!tmpval) return 0;
881         } else tmpval = NULL;
882         /* Parameter values are case sensitive so leave as is */
883         mparam = (MIME_PARAM *) OPENSSL_malloc(sizeof(MIME_PARAM));
884         if(!mparam) return 0;
885         mparam->param_name = tmpname;
886         mparam->param_value = tmpval;
887         sk_MIME_PARAM_push(mhdr->params, mparam);
888         return 1;
889 }
890
891 static int mime_hdr_cmp(const MIME_HEADER * const *a,
892                         const MIME_HEADER * const *b)
893 {
894         if (!(*a)->name || !(*b)->name)
895                 return !!(*a)->name - !!(*b)->name;
896
897         return(strcmp((*a)->name, (*b)->name));
898 }
899
900 static int mime_param_cmp(const MIME_PARAM * const *a,
901                         const MIME_PARAM * const *b)
902 {
903         if (!(*a)->param_name || !(*b)->param_name)
904                 return !!(*a)->param_name - !!(*b)->param_name;
905         return(strcmp((*a)->param_name, (*b)->param_name));
906 }
907
908 /* Find a header with a given name (if possible) */
909
910 static MIME_HEADER *mime_hdr_find(STACK_OF(MIME_HEADER) *hdrs, char *name)
911 {
912         MIME_HEADER htmp;
913         int idx;
914         htmp.name = name;
915         idx = sk_MIME_HEADER_find(hdrs, &htmp);
916         if(idx < 0) return NULL;
917         return sk_MIME_HEADER_value(hdrs, idx);
918 }
919
920 static MIME_PARAM *mime_param_find(MIME_HEADER *hdr, char *name)
921 {
922         MIME_PARAM param;
923         int idx;
924         param.param_name = name;
925         idx = sk_MIME_PARAM_find(hdr->params, &param);
926         if(idx < 0) return NULL;
927         return sk_MIME_PARAM_value(hdr->params, idx);
928 }
929
930 static void mime_hdr_free(MIME_HEADER *hdr)
931 {
932         if(hdr->name) OPENSSL_free(hdr->name);
933         if(hdr->value) OPENSSL_free(hdr->value);
934         if(hdr->params) sk_MIME_PARAM_pop_free(hdr->params, mime_param_free);
935         OPENSSL_free(hdr);
936 }
937
938 static void mime_param_free(MIME_PARAM *param)
939 {
940         if(param->param_name) OPENSSL_free(param->param_name);
941         if(param->param_value) OPENSSL_free(param->param_value);
942         OPENSSL_free(param);
943 }
944
945 /* Check for a multipart boundary. Returns:
946  * 0 : no boundary
947  * 1 : part boundary
948  * 2 : final boundary
949  */
950 static int mime_bound_check(char *line, int linelen, char *bound, int blen)
951 {
952         if(linelen == -1) linelen = strlen(line);
953         if(blen == -1) blen = strlen(bound);
954         /* Quickly eliminate if line length too short */
955         if(blen + 2 > linelen) return 0;
956         /* Check for part boundary */
957         if(!strncmp(line, "--", 2) && !strncmp(line + 2, bound, blen)) {
958                 if(!strncmp(line + blen + 2, "--", 2)) return 2;
959                 else return 1;
960         }
961         return 0;
962 }
963
964 static int strip_eol(char *linebuf, int *plen, int flags)
965         {
966         int len = *plen;
967         char *p, c;
968         int is_eol = 0;
969         p = linebuf + len - 1;
970         for (p = linebuf + len - 1; len > 0; len--, p--)
971                 {
972                 c = *p;
973                 if (c == '\n')
974                         is_eol = 1;
975                 else if (is_eol && flags & SMIME_ASCIICRLF && c < 33)
976                         continue;
977                 else if (c != '\r')
978                         break;
979                 }
980         *plen = len;
981         return is_eol;
982         }