1 /* $OpenBSD: asn_mime.c,v 1.27 2017/01/29 17:49:22 beck Exp $ */
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 <ctype.h>
56 #include <stdio.h>
57 #include <stdlib.h>
58 #include <string.h>
59
60 #include <openssl/asn1.h>
61 #include <openssl/asn1t.h>
62 #include <openssl/err.h>
63 #include <openssl/x509.h>
64
65 #include "asn1_locl.h"
66
67 /* Generalised MIME like utilities for streaming ASN1. Although many
68 * have a PKCS7/CMS like flavour others are more general purpose.
69 */
70
71 /* MIME format structures
72 * Note that all are translated to lower case apart from
73 * parameter values. Quotes are stripped off
74 */
75
76 typedef struct {
77 char *param_name; /* Param name e.g. "micalg" */
78 char *param_value; /* Param value e.g. "sha1" */
79 } MIME_PARAM;
80
81 DECLARE_STACK_OF(MIME_PARAM)
82
83 typedef struct {
84 char *name; /* Name of line e.g. "content-type" */
85 char *value; /* Value of line e.g. "text/plain" */
86 STACK_OF(MIME_PARAM) *params; /* Zero or more parameters */
87 } MIME_HEADER;
88
89 DECLARE_STACK_OF(MIME_HEADER)
90
91 static int asn1_output_data(BIO *out, BIO *data, ASN1_VALUE *val, int flags,
92 const ASN1_ITEM *it);
93 static char * strip_ends(char *name);
94 static char * strip_start(char *name);
95 static char * strip_end(char *name);
96 static MIME_HEADER *mime_hdr_new(char *name, char *value);
97 static int mime_hdr_addparam(MIME_HEADER *mhdr, char *name, char *value);
98 static STACK_OF(MIME_HEADER) *mime_parse_hdr(BIO *bio);
99 static int mime_hdr_cmp(const MIME_HEADER * const *a,
100 const MIME_HEADER * const *b);
101 static int mime_param_cmp(const MIME_PARAM * const *a,
102 const MIME_PARAM * const *b);
103 static void mime_param_free(MIME_PARAM *param);
104 static int mime_bound_check(char *line, int linelen, char *bound, int blen);
105 static int multi_split(BIO *bio, char *bound, STACK_OF(BIO) **ret);
106 static int strip_eol(char *linebuf, int *plen);
107 static MIME_HEADER *mime_hdr_find(STACK_OF(MIME_HEADER) *hdrs, char *name);
108 static MIME_PARAM *mime_param_find(MIME_HEADER *hdr, char *name);
109 static void mime_hdr_free(MIME_HEADER *hdr);
110
111 #define MAX_SMLEN 1024
112 #define mime_debug(x) /* x */
113
114 /* Output an ASN1 structure in BER format streaming if necessary */
115
116 int
i2d_ASN1_bio_stream(BIO * out,ASN1_VALUE * val,BIO * in,int flags,const ASN1_ITEM * it)117 i2d_ASN1_bio_stream(BIO *out, ASN1_VALUE *val, BIO *in, int flags,
118 const ASN1_ITEM *it)
119 {
120 /* If streaming create stream BIO and copy all content through it */
121 if (flags & SMIME_STREAM) {
122 BIO *bio, *tbio;
123 bio = BIO_new_NDEF(out, val, it);
124 if (!bio) {
125 ASN1error(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 tbio = BIO_pop(bio);
133 BIO_free(bio);
134 bio = tbio;
135 } while (bio != out);
136 }
137 /* else just write out ASN1 structure which will have all content
138 * stored internally
139 */
140 else
141 ASN1_item_i2d_bio(it, out, val);
142 return 1;
143 }
144
145 /* Base 64 read and write of ASN1 structure */
146
147 static int
B64_write_ASN1(BIO * out,ASN1_VALUE * val,BIO * in,int flags,const ASN1_ITEM * it)148 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
154 b64 = BIO_new(BIO_f_base64());
155 if (!b64) {
156 ASN1error(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,const char * hdr,const ASN1_ITEM * it)172 PEM_write_bio_ASN1_stream(BIO *out, ASN1_VALUE *val, BIO *in, int flags,
173 const char *hdr, const ASN1_ITEM *it)
174 {
175 int r;
176
177 BIO_printf(out, "-----BEGIN %s-----\n", hdr);
178 r = B64_write_ASN1(out, val, in, flags, it);
179 BIO_printf(out, "-----END %s-----\n", hdr);
180 return r;
181 }
182
183 static ASN1_VALUE *
b64_read_asn1(BIO * bio,const ASN1_ITEM * it)184 b64_read_asn1(BIO *bio, const ASN1_ITEM *it)
185 {
186 BIO *b64;
187 ASN1_VALUE *val;
188 if (!(b64 = BIO_new(BIO_f_base64()))) {
189 ASN1error(ERR_R_MALLOC_FAILURE);
190 return 0;
191 }
192 bio = BIO_push(b64, bio);
193 val = ASN1_item_d2i_bio(it, bio, NULL);
194 if (!val)
195 ASN1error(ASN1_R_DECODE_ERROR);
196 (void)BIO_flush(bio);
197 bio = BIO_pop(bio);
198 BIO_free(b64);
199 return val;
200 }
201
202 /* Generate the MIME "micalg" parameter from RFC3851, RFC4490 */
203
204 static int
asn1_write_micalg(BIO * out,STACK_OF (X509_ALGOR)* mdalgs)205 asn1_write_micalg(BIO *out, STACK_OF(X509_ALGOR) *mdalgs)
206 {
207 const EVP_MD *md;
208 int i, have_unknown = 0, write_comma, ret = 0, md_nid;
209
210 have_unknown = 0;
211 write_comma = 0;
212 for (i = 0; i < sk_X509_ALGOR_num(mdalgs); i++) {
213 if (write_comma)
214 BIO_write(out, ",", 1);
215 write_comma = 1;
216 md_nid = OBJ_obj2nid(sk_X509_ALGOR_value(mdalgs, i)->algorithm);
217 md = EVP_get_digestbynid(md_nid);
218 if (md && md->md_ctrl) {
219 int rv;
220 char *micstr;
221 rv = md->md_ctrl(NULL, EVP_MD_CTRL_MICALG, 0, &micstr);
222 if (rv > 0) {
223 BIO_puts(out, micstr);
224 free(micstr);
225 continue;
226 }
227 if (rv != -2)
228 goto err;
229 }
230 switch (md_nid) {
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 BIO_puts(out, "unknown");
261 have_unknown = 1;
262 }
263 break;
264
265 }
266 }
267
268 ret = 1;
269
270 err:
271 return ret;
272 }
273
274 /* SMIME sender */
275
276 int
SMIME_write_ASN1(BIO * bio,ASN1_VALUE * val,BIO * data,int flags,int ctype_nid,int econt_nid,STACK_OF (X509_ALGOR)* mdalgs,const ASN1_ITEM * it)277 SMIME_write_ASN1(BIO *bio, ASN1_VALUE *val, BIO *data, int flags,
278 int ctype_nid, int econt_nid, STACK_OF(X509_ALGOR) *mdalgs,
279 const ASN1_ITEM *it)
280 {
281 char bound[33], c;
282 int i;
283 const char *mime_prefix, *mime_eol, *cname = "smime.p7m";
284 const char *msg_type = NULL;
285
286 if (flags & SMIME_OLDMIME)
287 mime_prefix = "application/x-pkcs7-";
288 else
289 mime_prefix = "application/pkcs7-";
290
291 if (flags & SMIME_CRLFEOL)
292 mime_eol = "\r\n";
293 else
294 mime_eol = "\n";
295 if ((flags & SMIME_DETACHED) && data) {
296 /* We want multipart/signed */
297 /* Generate a random boundary */
298 arc4random_buf(bound, 32);
299 for (i = 0; i < 32; i++) {
300 c = bound[i] & 0xf;
301 if (c < 10)
302 c += '0';
303 else
304 c += 'A' - 10;
305 bound[i] = c;
306 }
307 bound[32] = 0;
308 BIO_printf(bio, "MIME-Version: 1.0%s", mime_eol);
309 BIO_printf(bio, "Content-Type: multipart/signed;");
310 BIO_printf(bio, " protocol=\"%ssignature\";", mime_prefix);
311 BIO_puts(bio, " micalg=\"");
312 asn1_write_micalg(bio, mdalgs);
313 BIO_printf(bio, "\"; boundary=\"----%s\"%s%s",
314 bound, mime_eol, mime_eol);
315 BIO_printf(bio, "This is an S/MIME signed message%s%s",
316 mime_eol, mime_eol);
317 /* Now write out the first part */
318 BIO_printf(bio, "------%s%s", bound, mime_eol);
319 if (!asn1_output_data(bio, data, val, flags, it))
320 return 0;
321 BIO_printf(bio, "%s------%s%s", mime_eol, bound, mime_eol);
322
323 /* Headers for signature */
324
325 BIO_printf(bio, "Content-Type: %ssignature;", mime_prefix);
326 BIO_printf(bio, " name=\"smime.p7s\"%s", mime_eol);
327 BIO_printf(bio, "Content-Transfer-Encoding: base64%s",
328 mime_eol);
329 BIO_printf(bio, "Content-Disposition: attachment;");
330 BIO_printf(bio, " filename=\"smime.p7s\"%s%s",
331 mime_eol, mime_eol);
332 B64_write_ASN1(bio, val, NULL, 0, it);
333 BIO_printf(bio, "%s------%s--%s%s", mime_eol, bound,
334 mime_eol, mime_eol);
335 return 1;
336 }
337
338 /* Determine smime-type header */
339
340 if (ctype_nid == NID_pkcs7_enveloped)
341 msg_type = "enveloped-data";
342 else if (ctype_nid == NID_pkcs7_signed) {
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 } else if (ctype_nid == NID_id_smime_ct_compressedData) {
350 msg_type = "compressed-data";
351 cname = "smime.p7z";
352 }
353 /* MIME headers */
354 BIO_printf(bio, "MIME-Version: 1.0%s", mime_eol);
355 BIO_printf(bio, "Content-Disposition: attachment;");
356 BIO_printf(bio, " filename=\"%s\"%s", cname, mime_eol);
357 BIO_printf(bio, "Content-Type: %smime;", mime_prefix);
358 if (msg_type)
359 BIO_printf(bio, " smime-type=%s;", msg_type);
360 BIO_printf(bio, " name=\"%s\"%s", cname, mime_eol);
361 BIO_printf(bio, "Content-Transfer-Encoding: base64%s%s",
362 mime_eol, mime_eol);
363 if (!B64_write_ASN1(bio, val, data, flags, it))
364 return 0;
365 BIO_printf(bio, "%s", mime_eol);
366 return 1;
367 }
368
369 /* Handle output of ASN1 data */
370
371
372 static int
asn1_output_data(BIO * out,BIO * data,ASN1_VALUE * val,int flags,const ASN1_ITEM * it)373 asn1_output_data(BIO *out, BIO *data, ASN1_VALUE *val, int flags,
374 const ASN1_ITEM *it)
375 {
376 BIO *tmpbio;
377 const ASN1_AUX *aux = it->funcs;
378 ASN1_STREAM_ARG sarg;
379 int rv = 1;
380
381 /* If data is not deteched or resigning then the output BIO is
382 * already set up to finalise when it is written through.
383 */
384 if (!(flags & SMIME_DETACHED) || (flags & PKCS7_REUSE_DIGEST)) {
385 SMIME_crlf_copy(data, out, flags);
386 return 1;
387 }
388
389 if (!aux || !aux->asn1_cb) {
390 ASN1error(ASN1_R_STREAMING_NOT_SUPPORTED);
391 return 0;
392 }
393
394 sarg.out = out;
395 sarg.ndef_bio = NULL;
396 sarg.boundary = NULL;
397
398 /* Let ASN1 code prepend any needed BIOs */
399
400 if (aux->asn1_cb(ASN1_OP_DETACHED_PRE, &val, it, &sarg) <= 0)
401 return 0;
402
403 /* Copy data across, passing through filter BIOs for processing */
404 SMIME_crlf_copy(data, sarg.ndef_bio, flags);
405
406 /* Finalize structure */
407 if (aux->asn1_cb(ASN1_OP_DETACHED_POST, &val, it, &sarg) <= 0)
408 rv = 0;
409
410 /* Now remove any digests prepended to the BIO */
411
412 while (sarg.ndef_bio != out) {
413 tmpbio = BIO_pop(sarg.ndef_bio);
414 BIO_free(sarg.ndef_bio);
415 sarg.ndef_bio = tmpbio;
416 }
417
418 return rv;
419 }
420
421 /* SMIME reader: handle multipart/signed and opaque signing.
422 * in multipart case the content is placed in a memory BIO
423 * pointed to by "bcont". In opaque this is set to NULL
424 */
425
426 ASN1_VALUE *
SMIME_read_ASN1(BIO * bio,BIO ** bcont,const ASN1_ITEM * it)427 SMIME_read_ASN1(BIO *bio, BIO **bcont, const ASN1_ITEM *it)
428 {
429 BIO *asnin;
430 STACK_OF(MIME_HEADER) *headers = NULL;
431 STACK_OF(BIO) *parts = NULL;
432 MIME_HEADER *hdr;
433 MIME_PARAM *prm;
434 ASN1_VALUE *val;
435 int ret;
436
437 if (bcont)
438 *bcont = NULL;
439
440 if (!(headers = mime_parse_hdr(bio))) {
441 ASN1error(ASN1_R_MIME_PARSE_ERROR);
442 return NULL;
443 }
444
445 if (!(hdr = mime_hdr_find(headers, "content-type")) || !hdr->value) {
446 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
447 ASN1error(ASN1_R_NO_CONTENT_TYPE);
448 return NULL;
449 }
450
451 /* Handle multipart/signed */
452
453 if (!strcmp(hdr->value, "multipart/signed")) {
454 /* Split into two parts */
455 prm = mime_param_find(hdr, "boundary");
456 if (!prm || !prm->param_value) {
457 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
458 ASN1error(ASN1_R_NO_MULTIPART_BOUNDARY);
459 return NULL;
460 }
461 ret = multi_split(bio, prm->param_value, &parts);
462 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
463 if (!ret || (sk_BIO_num(parts) != 2) ) {
464 ASN1error(ASN1_R_NO_MULTIPART_BODY_FAILURE);
465 sk_BIO_pop_free(parts, BIO_vfree);
466 return NULL;
467 }
468
469 /* Parse the signature piece */
470 asnin = sk_BIO_value(parts, 1);
471
472 if (!(headers = mime_parse_hdr(asnin))) {
473 ASN1error(ASN1_R_MIME_SIG_PARSE_ERROR);
474 sk_BIO_pop_free(parts, BIO_vfree);
475 return NULL;
476 }
477
478 /* Get content type */
479
480 if (!(hdr = mime_hdr_find(headers, "content-type")) ||
481 !hdr->value) {
482 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
483 sk_BIO_pop_free(parts, BIO_vfree);
484 ASN1error(ASN1_R_NO_SIG_CONTENT_TYPE);
485 return NULL;
486 }
487
488 if (strcmp(hdr->value, "application/x-pkcs7-signature") &&
489 strcmp(hdr->value, "application/pkcs7-signature")) {
490 ASN1error(ASN1_R_SIG_INVALID_MIME_TYPE);
491 ERR_asprintf_error_data("type: %s", hdr->value);
492 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
493 sk_BIO_pop_free(parts, BIO_vfree);
494 return NULL;
495 }
496 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
497 /* Read in ASN1 */
498 if (!(val = b64_read_asn1(asnin, it))) {
499 ASN1error(ASN1_R_ASN1_SIG_PARSE_ERROR);
500 sk_BIO_pop_free(parts, BIO_vfree);
501 return NULL;
502 }
503
504 if (bcont) {
505 *bcont = sk_BIO_value(parts, 0);
506 BIO_free(asnin);
507 sk_BIO_free(parts);
508 } else sk_BIO_pop_free(parts, BIO_vfree);
509 return val;
510 }
511
512 /* OK, if not multipart/signed try opaque signature */
513
514 if (strcmp (hdr->value, "application/x-pkcs7-mime") &&
515 strcmp (hdr->value, "application/pkcs7-mime")) {
516 ASN1error(ASN1_R_INVALID_MIME_TYPE);
517 ERR_asprintf_error_data("type: %s", hdr->value);
518 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
519 return NULL;
520 }
521
522 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
523
524 if (!(val = b64_read_asn1(bio, it))) {
525 ASN1error(ASN1_R_ASN1_PARSE_ERROR);
526 return NULL;
527 }
528 return val;
529 }
530
531 /* Copy text from one BIO to another making the output CRLF at EOL */
532 int
SMIME_crlf_copy(BIO * in,BIO * out,int flags)533 SMIME_crlf_copy(BIO *in, BIO *out, int flags)
534 {
535 BIO *bf;
536 char eol;
537 int len;
538 char linebuf[MAX_SMLEN];
539
540 /* Buffer output so we don't write one line at a time. This is
541 * useful when streaming as we don't end up with one OCTET STRING
542 * per line.
543 */
544 bf = BIO_new(BIO_f_buffer());
545 if (!bf)
546 return 0;
547 out = BIO_push(bf, out);
548 if (flags & SMIME_BINARY) {
549 while ((len = BIO_read(in, linebuf, MAX_SMLEN)) > 0)
550 BIO_write(out, linebuf, len);
551 } else {
552 if (flags & SMIME_TEXT)
553 BIO_printf(out, "Content-Type: text/plain\r\n\r\n");
554 while ((len = BIO_gets(in, linebuf, MAX_SMLEN)) > 0) {
555 eol = strip_eol(linebuf, &len);
556 if (len)
557 BIO_write(out, linebuf, len);
558 if (eol)
559 BIO_write(out, "\r\n", 2);
560 }
561 }
562 (void)BIO_flush(out);
563 BIO_pop(out);
564 BIO_free(bf);
565 return 1;
566 }
567
568 /* Strip off headers if they are text/plain */
569 int
SMIME_text(BIO * in,BIO * out)570 SMIME_text(BIO *in, BIO *out)
571 {
572 char iobuf[4096];
573 int len;
574 STACK_OF(MIME_HEADER) *headers;
575 MIME_HEADER *hdr;
576
577 if (!(headers = mime_parse_hdr(in))) {
578 ASN1error(ASN1_R_MIME_PARSE_ERROR);
579 return 0;
580 }
581 if (!(hdr = mime_hdr_find(headers, "content-type")) || !hdr->value) {
582 ASN1error(ASN1_R_MIME_NO_CONTENT_TYPE);
583 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
584 return 0;
585 }
586 if (strcmp (hdr->value, "text/plain")) {
587 ASN1error(ASN1_R_INVALID_MIME_TYPE);
588 ERR_asprintf_error_data("type: %s", hdr->value);
589 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
590 return 0;
591 }
592 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
593 while ((len = BIO_read(in, iobuf, sizeof(iobuf))) > 0)
594 BIO_write(out, iobuf, len);
595 if (len < 0)
596 return 0;
597 return 1;
598 }
599
600 /*
601 * Split a multipart/XXX message body into component parts: result is
602 * canonical parts in a STACK of bios
603 */
604 static int
multi_split(BIO * bio,char * bound,STACK_OF (BIO)** ret)605 multi_split(BIO *bio, char *bound, STACK_OF(BIO) **ret)
606 {
607 char linebuf[MAX_SMLEN];
608 int len, blen;
609 int eol = 0, next_eol = 0;
610 BIO *bpart = NULL;
611 STACK_OF(BIO) *parts;
612 char state, part, first;
613
614 blen = strlen(bound);
615 part = 0;
616 state = 0;
617 first = 1;
618 parts = sk_BIO_new_null();
619 *ret = parts;
620 if (parts == NULL)
621 return 0;
622 while ((len = BIO_gets(bio, linebuf, MAX_SMLEN)) > 0) {
623 state = mime_bound_check(linebuf, len, bound, blen);
624 if (state == 1) {
625 first = 1;
626 part++;
627 } else if (state == 2) {
628 if (sk_BIO_push(parts, bpart) == 0)
629 return 0;
630 return 1;
631 } else if (part) {
632 /* Strip CR+LF from linebuf */
633 next_eol = strip_eol(linebuf, &len);
634 if (first) {
635 first = 0;
636 if (bpart != NULL) {
637 if (sk_BIO_push(parts, bpart) == 0)
638 return 0;
639 }
640 bpart = BIO_new(BIO_s_mem());
641 if (bpart == NULL)
642 return 0;
643 BIO_set_mem_eof_return(bpart, 0);
644 } else if (eol)
645 BIO_write(bpart, "\r\n", 2);
646 eol = next_eol;
647 if (len)
648 BIO_write(bpart, linebuf, len);
649 }
650 }
651 BIO_free(bpart);
652 return 0;
653 }
654
655 /* This is the big one: parse MIME header lines up to message body */
656
657 #define MIME_INVALID 0
658 #define MIME_START 1
659 #define MIME_TYPE 2
660 #define MIME_NAME 3
661 #define MIME_VALUE 4
662 #define MIME_QUOTE 5
663 #define MIME_COMMENT 6
664
665
666 static
STACK_OF(MIME_HEADER)667 STACK_OF(MIME_HEADER) *mime_parse_hdr(BIO *bio)
668 {
669 char *p, *q, c;
670 char *ntmp;
671 char linebuf[MAX_SMLEN];
672 MIME_HEADER *mhdr = NULL;
673 STACK_OF(MIME_HEADER) *headers;
674 int len, state, save_state = 0;
675
676 headers = sk_MIME_HEADER_new(mime_hdr_cmp);
677 if (!headers)
678 return NULL;
679 while ((len = BIO_gets(bio, linebuf, MAX_SMLEN)) > 0) {
680 /* If whitespace at line start then continuation line */
681 if (mhdr && isspace((unsigned char)linebuf[0]))
682 state = MIME_NAME;
683 else
684 state = MIME_START;
685 ntmp = NULL;
686
687 /* Go through all characters */
688 for (p = linebuf, q = linebuf;
689 (c = *p) && (c != '\r') && (c != '\n'); p++) {
690
691 /* State machine to handle MIME headers
692 * if this looks horrible that's because it *is*
693 */
694
695 switch (state) {
696 case MIME_START:
697 if (c == ':') {
698 state = MIME_TYPE;
699 *p = 0;
700 ntmp = strip_ends(q);
701 q = p + 1;
702 }
703 break;
704
705 case MIME_TYPE:
706 if (c == ';') {
707 mime_debug("Found End Value\n");
708 *p = 0;
709 mhdr = mime_hdr_new(ntmp,
710 strip_ends(q));
711 if (mhdr == NULL)
712 goto merr;
713 if (sk_MIME_HEADER_push(headers,
714 mhdr) == 0)
715 goto merr;
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,
745 strip_ends(q));
746 ntmp = NULL;
747 q = p + 1;
748 } else if (c == '"') {
749 mime_debug("Found Quote\n");
750 state = MIME_QUOTE;
751 } else if (c == '(') {
752 save_state = state;
753 state = MIME_COMMENT;
754 }
755 break;
756
757 case MIME_QUOTE:
758 if (c == '"') {
759 mime_debug("Found Match Quote\n");
760 state = MIME_VALUE;
761 }
762 break;
763 }
764 }
765
766 if (state == MIME_TYPE) {
767 mhdr = mime_hdr_new(ntmp, strip_ends(q));
768 if (mhdr == NULL)
769 goto merr;
770 if (sk_MIME_HEADER_push(headers, mhdr) == 0)
771 goto merr;
772 } else if (state == MIME_VALUE)
773 mime_hdr_addparam(mhdr, ntmp, strip_ends(q));
774
775 if (p == linebuf)
776 break; /* Blank line means end of headers */
777 }
778
779 return headers;
780
781 merr:
782 if (mhdr != NULL)
783 mime_hdr_free(mhdr);
784 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
785 return NULL;
786 }
787
788 static char *
strip_ends(char * name)789 strip_ends(char *name)
790 {
791 return strip_end(strip_start(name));
792 }
793
794 /* Strip a parameter of whitespace from start of param */
795 static char *
strip_start(char * name)796 strip_start(char *name)
797 {
798 char *p, c;
799
800 /* Look for first non white space or quote */
801 for (p = name; (c = *p); p++) {
802 if (c == '"') {
803 /* Next char is start of string if non null */
804 if (p[1])
805 return p + 1;
806 /* Else null string */
807 return NULL;
808 }
809 if (!isspace((unsigned char)c))
810 return p;
811 }
812 return NULL;
813 }
814
815 /* As above but strip from end of string : maybe should handle brackets? */
816 static char *
strip_end(char * name)817 strip_end(char *name)
818 {
819 char *p, c;
820
821 if (!name)
822 return NULL;
823
824 /* Look for first non white space or quote */
825 for (p = name + strlen(name) - 1; p >= name; p--) {
826 c = *p;
827 if (c == '"') {
828 if (p - 1 == name)
829 return NULL;
830 *p = 0;
831 return name;
832 }
833 if (isspace((unsigned char)c))
834 *p = 0;
835 else
836 return name;
837 }
838 return NULL;
839 }
840
841 static MIME_HEADER *
mime_hdr_new(char * name,char * value)842 mime_hdr_new(char *name, char *value)
843 {
844 MIME_HEADER *mhdr;
845 char *tmpname = NULL, *tmpval = NULL, *p;
846
847 if (name) {
848 if (!(tmpname = strdup(name)))
849 goto err;
850 for (p = tmpname; *p; p++)
851 *p = tolower((unsigned char)*p);
852 }
853 if (value) {
854 if (!(tmpval = strdup(value)))
855 goto err;
856 for (p = tmpval; *p; p++)
857 *p = tolower((unsigned char)*p);
858 }
859 mhdr = malloc(sizeof(MIME_HEADER));
860 if (!mhdr)
861 goto err;
862 mhdr->name = tmpname;
863 mhdr->value = tmpval;
864 if (!(mhdr->params = sk_MIME_PARAM_new(mime_param_cmp))) {
865 free(mhdr);
866 goto err;
867 }
868 return mhdr;
869 err:
870 free(tmpname);
871 free(tmpval);
872 return NULL;
873 }
874
875 static int
mime_hdr_addparam(MIME_HEADER * mhdr,char * name,char * value)876 mime_hdr_addparam(MIME_HEADER *mhdr, char *name, char *value)
877 {
878 char *tmpname = NULL, *tmpval = NULL, *p;
879 MIME_PARAM *mparam;
880
881 if (name) {
882 tmpname = strdup(name);
883 if (!tmpname)
884 goto err;
885 for (p = tmpname; *p; p++)
886 *p = tolower((unsigned char)*p);
887 }
888 if (value) {
889 tmpval = strdup(value);
890 if (!tmpval)
891 goto err;
892 }
893 /* Parameter values are case sensitive so leave as is */
894 mparam = malloc(sizeof(MIME_PARAM));
895 if (!mparam)
896 goto err;
897 mparam->param_name = tmpname;
898 mparam->param_value = tmpval;
899 if (sk_MIME_PARAM_push(mhdr->params, mparam) == 0) {
900 free(mparam);
901 goto err;
902 }
903 return 1;
904 err:
905 free(tmpname);
906 free(tmpval);
907 return 0;
908 }
909
910 static int
mime_hdr_cmp(const MIME_HEADER * const * a,const MIME_HEADER * const * b)911 mime_hdr_cmp(const MIME_HEADER * const *a, const MIME_HEADER * const *b)
912 {
913 if (!(*a)->name || !(*b)->name)
914 return !!(*a)->name - !!(*b)->name;
915 return (strcmp((*a)->name, (*b)->name));
916 }
917
918 static int
mime_param_cmp(const MIME_PARAM * const * a,const MIME_PARAM * const * b)919 mime_param_cmp(const MIME_PARAM * const *a, const MIME_PARAM * const *b)
920 {
921 if (!(*a)->param_name || !(*b)->param_name)
922 return !!(*a)->param_name - !!(*b)->param_name;
923 return (strcmp((*a)->param_name, (*b)->param_name));
924 }
925
926 /* Find a header with a given name (if possible) */
927
928 static MIME_HEADER *
mime_hdr_find(STACK_OF (MIME_HEADER)* hdrs,char * name)929 mime_hdr_find(STACK_OF(MIME_HEADER) *hdrs, char *name)
930 {
931 MIME_HEADER htmp;
932 int idx;
933 htmp.name = name;
934 idx = sk_MIME_HEADER_find(hdrs, &htmp);
935 if (idx < 0)
936 return NULL;
937 return sk_MIME_HEADER_value(hdrs, idx);
938 }
939
940 static MIME_PARAM *
mime_param_find(MIME_HEADER * hdr,char * name)941 mime_param_find(MIME_HEADER *hdr, char *name)
942 {
943 MIME_PARAM param;
944 int idx;
945 param.param_name = name;
946 idx = sk_MIME_PARAM_find(hdr->params, ¶m);
947 if (idx < 0)
948 return NULL;
949 return sk_MIME_PARAM_value(hdr->params, idx);
950 }
951
952 static void
mime_hdr_free(MIME_HEADER * hdr)953 mime_hdr_free(MIME_HEADER *hdr)
954 {
955 free(hdr->name);
956 free(hdr->value);
957 if (hdr->params)
958 sk_MIME_PARAM_pop_free(hdr->params, mime_param_free);
959 free(hdr);
960 }
961
962 static void
mime_param_free(MIME_PARAM * param)963 mime_param_free(MIME_PARAM *param)
964 {
965 free(param->param_name);
966 free(param->param_value);
967 free(param);
968 }
969
970 /* Check for a multipart boundary. Returns:
971 * 0 : no boundary
972 * 1 : part boundary
973 * 2 : final boundary
974 */
975 static int
mime_bound_check(char * line,int linelen,char * bound,int blen)976 mime_bound_check(char *line, int linelen, char *bound, int blen)
977 {
978 if (linelen == -1)
979 linelen = strlen(line);
980 if (blen == -1)
981 blen = strlen(bound);
982 /* Quickly eliminate if line length too short */
983 if (blen + 2 > linelen)
984 return 0;
985 /* Check for part boundary */
986 if (!strncmp(line, "--", 2) && !strncmp(line + 2, bound, blen)) {
987 if (!strncmp(line + blen + 2, "--", 2))
988 return 2;
989 else
990 return 1;
991 }
992 return 0;
993 }
994
995 static int
strip_eol(char * linebuf,int * plen)996 strip_eol(char *linebuf, int *plen)
997 {
998 int len = *plen;
999 char *p, c;
1000 int is_eol = 0;
1001
1002 for (p = linebuf + len - 1; len > 0; len--, p--) {
1003 c = *p;
1004 if (c == '\n')
1005 is_eol = 1;
1006 else if (c != '\r')
1007 break;
1008 }
1009 *plen = len;
1010 return is_eol;
1011 }
1012