1 /*
2 * Copyright 2008-2022 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10 #include <stdio.h>
11 #include "crypto/ctype.h"
12 #include "internal/cryptlib.h"
13 #include <openssl/rand.h>
14 #include <openssl/x509.h>
15 #include <openssl/asn1.h>
16 #include <openssl/asn1t.h>
17 #include <openssl/cms.h>
18 #include "crypto/evp.h"
19 #include "internal/bio.h"
20 #include "asn1_local.h"
21
22 /*
23 * Generalised MIME like utilities for streaming ASN1. Although many have a
24 * PKCS7/CMS like flavour others are more general purpose.
25 */
26
27 /*
28 * MIME format structures Note that all are translated to lower case apart
29 * from parameter values. Quotes are stripped off
30 */
31
32 struct mime_param_st {
33 char *param_name; /* Param name e.g. "micalg" */
34 char *param_value; /* Param value e.g. "sha1" */
35 };
36
37 struct mime_header_st {
38 char *name; /* Name of line e.g. "content-type" */
39 char *value; /* Value of line e.g. "text/plain" */
40 STACK_OF(MIME_PARAM) *params; /* Zero or more parameters */
41 };
42
43 static int asn1_output_data(BIO *out, BIO *data, ASN1_VALUE *val, int flags,
44 const ASN1_ITEM *it);
45 static char *strip_ends(char *name);
46 static char *strip_start(char *name);
47 static char *strip_end(char *name);
48 static MIME_HEADER *mime_hdr_new(const char *name, const char *value);
49 static int mime_hdr_addparam(MIME_HEADER *mhdr, const char *name, const char *value);
50 static STACK_OF(MIME_HEADER) *mime_parse_hdr(BIO *bio);
51 static int mime_hdr_cmp(const MIME_HEADER *const *a,
52 const MIME_HEADER *const *b);
53 static int mime_param_cmp(const MIME_PARAM *const *a,
54 const MIME_PARAM *const *b);
55 static void mime_param_free(MIME_PARAM *param);
56 static int mime_bound_check(char *line, int linelen, const char *bound, int blen);
57 static int multi_split(BIO *bio, int flags, const char *bound, STACK_OF(BIO) **ret);
58 static int strip_eol(char *linebuf, int *plen, int flags);
59 static MIME_HEADER *mime_hdr_find(STACK_OF(MIME_HEADER) *hdrs, const char *name);
60 static MIME_PARAM *mime_param_find(MIME_HEADER *hdr, const char *name);
61 static void mime_hdr_free(MIME_HEADER *hdr);
62
63 #define MAX_SMLEN 1024
64 #define mime_debug(x) /* x */
65
66 /* Output an ASN1 structure in BER format streaming if necessary */
67
68 /* unfortunately cannot constify this due to CMS_stream() and PKCS7_stream() */
i2d_ASN1_bio_stream(BIO * out,ASN1_VALUE * val,BIO * in,int flags,const ASN1_ITEM * it)69 int i2d_ASN1_bio_stream(BIO *out, ASN1_VALUE *val, BIO *in, int flags,
70 const ASN1_ITEM *it)
71 {
72 int rv = 1;
73
74 /* If streaming create stream BIO and copy all content through it */
75 if (flags & SMIME_STREAM) {
76 BIO *bio, *tbio;
77 bio = BIO_new_NDEF(out, val, it);
78 if (!bio) {
79 ERR_raise(ERR_LIB_ASN1, ERR_R_MALLOC_FAILURE);
80 return 0;
81 }
82 if (!SMIME_crlf_copy(in, bio, flags)) {
83 rv = 0;
84 }
85
86 (void)BIO_flush(bio);
87 /* Free up successive BIOs until we hit the old output BIO */
88 do {
89 tbio = BIO_pop(bio);
90 BIO_free(bio);
91 bio = tbio;
92 } while (bio != out);
93 }
94 /*
95 * else just write out ASN1 structure which will have all content stored
96 * internally
97 */
98 else
99 ASN1_item_i2d_bio(it, out, val);
100 return rv;
101 }
102
103 /* Base 64 read and write of ASN1 structure */
104
B64_write_ASN1(BIO * out,ASN1_VALUE * val,BIO * in,int flags,const ASN1_ITEM * it)105 static int B64_write_ASN1(BIO *out, ASN1_VALUE *val, BIO *in, int flags,
106 const ASN1_ITEM *it)
107 {
108 BIO *b64;
109 int r;
110 b64 = BIO_new(BIO_f_base64());
111 if (b64 == NULL) {
112 ERR_raise(ERR_LIB_ASN1, ERR_R_MALLOC_FAILURE);
113 return 0;
114 }
115 /*
116 * prepend the b64 BIO so all data is base64 encoded.
117 */
118 out = BIO_push(b64, out);
119 r = i2d_ASN1_bio_stream(out, val, in, flags, it);
120 (void)BIO_flush(out);
121 BIO_pop(out);
122 BIO_free(b64);
123 return r;
124 }
125
126 /* Streaming ASN1 PEM write */
127
PEM_write_bio_ASN1_stream(BIO * out,ASN1_VALUE * val,BIO * in,int flags,const char * hdr,const ASN1_ITEM * it)128 int PEM_write_bio_ASN1_stream(BIO *out, ASN1_VALUE *val, BIO *in, int flags,
129 const char *hdr, const ASN1_ITEM *it)
130 {
131 int r;
132 BIO_printf(out, "-----BEGIN %s-----\n", hdr);
133 r = B64_write_ASN1(out, val, in, flags, it);
134 BIO_printf(out, "-----END %s-----\n", hdr);
135 return r;
136 }
137
b64_read_asn1(BIO * bio,const ASN1_ITEM * it,ASN1_VALUE ** x,OSSL_LIB_CTX * libctx,const char * propq)138 static ASN1_VALUE *b64_read_asn1(BIO *bio, const ASN1_ITEM *it, ASN1_VALUE **x,
139 OSSL_LIB_CTX *libctx, const char *propq)
140 {
141 BIO *b64;
142 ASN1_VALUE *val;
143
144 if ((b64 = BIO_new(BIO_f_base64())) == NULL) {
145 ERR_raise(ERR_LIB_ASN1, ERR_R_MALLOC_FAILURE);
146 return 0;
147 }
148 bio = BIO_push(b64, bio);
149 val = ASN1_item_d2i_bio_ex(it, bio, x, libctx, propq);
150 if (!val)
151 ERR_raise(ERR_LIB_ASN1, ASN1_R_DECODE_ERROR);
152 (void)BIO_flush(bio);
153 BIO_pop(bio);
154 BIO_free(b64);
155 return val;
156 }
157
158 /* Generate the MIME "micalg" parameter from RFC3851, RFC4490 */
159
asn1_write_micalg(BIO * out,STACK_OF (X509_ALGOR)* mdalgs)160 static int asn1_write_micalg(BIO *out, STACK_OF(X509_ALGOR) *mdalgs)
161 {
162 const EVP_MD *md;
163 int i, have_unknown = 0, write_comma, ret = 0, md_nid;
164 have_unknown = 0;
165 write_comma = 0;
166 for (i = 0; i < sk_X509_ALGOR_num(mdalgs); i++) {
167 if (write_comma)
168 BIO_write(out, ",", 1);
169 write_comma = 1;
170 md_nid = OBJ_obj2nid(sk_X509_ALGOR_value(mdalgs, i)->algorithm);
171 md = EVP_get_digestbynid(md_nid);
172 if (md && md->md_ctrl) {
173 int rv;
174 char *micstr;
175 rv = md->md_ctrl(NULL, EVP_MD_CTRL_MICALG, 0, &micstr);
176 if (rv > 0) {
177 BIO_puts(out, micstr);
178 OPENSSL_free(micstr);
179 continue;
180 }
181 if (rv != -2)
182 goto err;
183 }
184 switch (md_nid) {
185 case NID_sha1:
186 BIO_puts(out, "sha1");
187 break;
188
189 case NID_md5:
190 BIO_puts(out, "md5");
191 break;
192
193 case NID_sha256:
194 BIO_puts(out, "sha-256");
195 break;
196
197 case NID_sha384:
198 BIO_puts(out, "sha-384");
199 break;
200
201 case NID_sha512:
202 BIO_puts(out, "sha-512");
203 break;
204
205 case NID_id_GostR3411_94:
206 BIO_puts(out, "gostr3411-94");
207 goto err;
208
209 case NID_id_GostR3411_2012_256:
210 BIO_puts(out, "gostr3411-2012-256");
211 goto err;
212
213 case NID_id_GostR3411_2012_512:
214 BIO_puts(out, "gostr3411-2012-512");
215 goto err;
216
217 default:
218 if (have_unknown) {
219 write_comma = 0;
220 } else {
221 BIO_puts(out, "unknown");
222 have_unknown = 1;
223 }
224 break;
225
226 }
227 }
228
229 ret = 1;
230 err:
231
232 return ret;
233
234 }
235
236 /* SMIME sender */
237
SMIME_write_ASN1_ex(BIO * bio,ASN1_VALUE * val,BIO * data,int flags,int ctype_nid,int econt_nid,STACK_OF (X509_ALGOR)* mdalgs,const ASN1_ITEM * it,OSSL_LIB_CTX * libctx,const char * propq)238 int SMIME_write_ASN1_ex(BIO *bio, ASN1_VALUE *val, BIO *data, int flags,
239 int ctype_nid, int econt_nid,
240 STACK_OF(X509_ALGOR) *mdalgs, const ASN1_ITEM *it,
241 OSSL_LIB_CTX *libctx, const char *propq)
242 {
243 char bound[33], c;
244 int i;
245 const char *mime_prefix, *mime_eol, *cname = "smime.p7m";
246 const char *msg_type = NULL;
247
248 if (flags & SMIME_OLDMIME)
249 mime_prefix = "application/x-pkcs7-";
250 else
251 mime_prefix = "application/pkcs7-";
252
253 if (flags & SMIME_CRLFEOL)
254 mime_eol = "\r\n";
255 else
256 mime_eol = "\n";
257 if ((flags & SMIME_DETACHED) && data) {
258 /* We want multipart/signed */
259 /* Generate a random boundary */
260 if (RAND_bytes_ex(libctx, (unsigned char *)bound, 32, 0) <= 0)
261 return 0;
262 for (i = 0; i < 32; i++) {
263 c = bound[i] & 0xf;
264 if (c < 10)
265 c += '0';
266 else
267 c += 'A' - 10;
268 bound[i] = c;
269 }
270 bound[32] = 0;
271 BIO_printf(bio, "MIME-Version: 1.0%s", mime_eol);
272 BIO_printf(bio, "Content-Type: multipart/signed;");
273 BIO_printf(bio, " protocol=\"%ssignature\";", mime_prefix);
274 BIO_puts(bio, " micalg=\"");
275 asn1_write_micalg(bio, mdalgs);
276 BIO_printf(bio, "\"; boundary=\"----%s\"%s%s",
277 bound, mime_eol, mime_eol);
278 BIO_printf(bio, "This is an S/MIME signed message%s%s",
279 mime_eol, mime_eol);
280 /* Now write out the first part */
281 BIO_printf(bio, "------%s%s", bound, mime_eol);
282 if (!asn1_output_data(bio, data, val, flags, it))
283 return 0;
284 BIO_printf(bio, "%s------%s%s", mime_eol, bound, mime_eol);
285
286 /* Headers for signature */
287
288 BIO_printf(bio, "Content-Type: %ssignature;", mime_prefix);
289 BIO_printf(bio, " name=\"smime.p7s\"%s", mime_eol);
290 BIO_printf(bio, "Content-Transfer-Encoding: base64%s", mime_eol);
291 BIO_printf(bio, "Content-Disposition: attachment;");
292 BIO_printf(bio, " filename=\"smime.p7s\"%s%s", mime_eol, mime_eol);
293 B64_write_ASN1(bio, val, NULL, 0, it);
294 BIO_printf(bio, "%s------%s--%s%s", mime_eol, bound,
295 mime_eol, mime_eol);
296 return 1;
297 }
298
299 /* Determine smime-type header */
300
301 if (ctype_nid == NID_pkcs7_enveloped) {
302 msg_type = "enveloped-data";
303 } else if (ctype_nid == NID_pkcs7_signed) {
304 if (econt_nid == NID_id_smime_ct_receipt)
305 msg_type = "signed-receipt";
306 else if (sk_X509_ALGOR_num(mdalgs) >= 0)
307 msg_type = "signed-data";
308 else
309 msg_type = "certs-only";
310 } else if (ctype_nid == NID_id_smime_ct_compressedData) {
311 msg_type = "compressed-data";
312 cname = "smime.p7z";
313 }
314 /* MIME headers */
315 BIO_printf(bio, "MIME-Version: 1.0%s", mime_eol);
316 BIO_printf(bio, "Content-Disposition: attachment;");
317 BIO_printf(bio, " filename=\"%s\"%s", cname, mime_eol);
318 BIO_printf(bio, "Content-Type: %smime;", mime_prefix);
319 if (msg_type)
320 BIO_printf(bio, " smime-type=%s;", msg_type);
321 BIO_printf(bio, " name=\"%s\"%s", cname, mime_eol);
322 BIO_printf(bio, "Content-Transfer-Encoding: base64%s%s",
323 mime_eol, mime_eol);
324 if (!B64_write_ASN1(bio, val, data, flags, it))
325 return 0;
326 BIO_printf(bio, "%s", mime_eol);
327 return 1;
328 }
329
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)330 int SMIME_write_ASN1(BIO *bio, ASN1_VALUE *val, BIO *data, int flags,
331 int ctype_nid, int econt_nid,
332 STACK_OF(X509_ALGOR) *mdalgs, const ASN1_ITEM *it)
333 {
334 return SMIME_write_ASN1_ex(bio, val, data, flags, ctype_nid, econt_nid,
335 mdalgs, it, NULL, NULL);
336 }
337
338 /* Handle output of ASN1 data */
339
340 /* cannot constify val because of CMS_dataFinal() */
asn1_output_data(BIO * out,BIO * data,ASN1_VALUE * val,int flags,const ASN1_ITEM * it)341 static int asn1_output_data(BIO *out, BIO *data, ASN1_VALUE *val, int flags,
342 const ASN1_ITEM *it)
343 {
344 BIO *tmpbio;
345 const ASN1_AUX *aux = it->funcs;
346 ASN1_STREAM_ARG sarg;
347 int rv = 1;
348
349 /*
350 * If data is not detached or resigning then the output BIO is already
351 * set up to finalise when it is written through.
352 */
353 if (!(flags & SMIME_DETACHED) || (flags & PKCS7_REUSE_DIGEST)) {
354 return SMIME_crlf_copy(data, out, flags);
355 }
356
357 if (!aux || !aux->asn1_cb) {
358 ERR_raise(ERR_LIB_ASN1, ASN1_R_STREAMING_NOT_SUPPORTED);
359 return 0;
360 }
361
362 sarg.out = out;
363 sarg.ndef_bio = NULL;
364 sarg.boundary = NULL;
365
366 /* Let ASN1 code prepend any needed BIOs */
367
368 if (aux->asn1_cb(ASN1_OP_DETACHED_PRE, &val, it, &sarg) <= 0)
369 return 0;
370
371 /* Copy data across, passing through filter BIOs for processing */
372 if (!SMIME_crlf_copy(data, sarg.ndef_bio, flags))
373 rv = 0;
374
375 /* Finalize structure */
376 if (aux->asn1_cb(ASN1_OP_DETACHED_POST, &val, it, &sarg) <= 0)
377 rv = 0;
378
379 /* Now remove any digests prepended to the BIO */
380
381 while (sarg.ndef_bio != out) {
382 tmpbio = BIO_pop(sarg.ndef_bio);
383 BIO_free(sarg.ndef_bio);
384 sarg.ndef_bio = tmpbio;
385 }
386
387 return rv;
388
389 }
390
391 /*
392 * SMIME reader: handle multipart/signed and opaque signing. in multipart
393 * case the content is placed in a memory BIO pointed to by "bcont". In
394 * opaque this is set to NULL
395 */
396
SMIME_read_ASN1_ex(BIO * bio,int flags,BIO ** bcont,const ASN1_ITEM * it,ASN1_VALUE ** x,OSSL_LIB_CTX * libctx,const char * propq)397 ASN1_VALUE *SMIME_read_ASN1_ex(BIO *bio, int flags, BIO **bcont,
398 const ASN1_ITEM *it, ASN1_VALUE **x,
399 OSSL_LIB_CTX *libctx, const char *propq)
400 {
401 BIO *asnin;
402 STACK_OF(MIME_HEADER) *headers = NULL;
403 STACK_OF(BIO) *parts = NULL;
404 MIME_HEADER *hdr;
405 MIME_PARAM *prm;
406 ASN1_VALUE *val;
407 int ret;
408
409 if (bcont)
410 *bcont = NULL;
411
412 if ((headers = mime_parse_hdr(bio)) == NULL) {
413 ERR_raise(ERR_LIB_ASN1, ASN1_R_MIME_PARSE_ERROR);
414 return NULL;
415 }
416
417 if ((hdr = mime_hdr_find(headers, "content-type")) == NULL
418 || hdr->value == NULL) {
419 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
420 ERR_raise(ERR_LIB_ASN1, ASN1_R_NO_CONTENT_TYPE);
421 return NULL;
422 }
423
424 /* Handle multipart/signed */
425
426 if (strcmp(hdr->value, "multipart/signed") == 0) {
427 /* Split into two parts */
428 prm = mime_param_find(hdr, "boundary");
429 if (prm == NULL || prm->param_value == NULL) {
430 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
431 ERR_raise(ERR_LIB_ASN1, ASN1_R_NO_MULTIPART_BOUNDARY);
432 return NULL;
433 }
434 ret = multi_split(bio, flags, prm->param_value, &parts);
435 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
436 if (!ret || (sk_BIO_num(parts) != 2)) {
437 ERR_raise(ERR_LIB_ASN1, ASN1_R_NO_MULTIPART_BODY_FAILURE);
438 sk_BIO_pop_free(parts, BIO_vfree);
439 return NULL;
440 }
441
442 /* Parse the signature piece */
443 asnin = sk_BIO_value(parts, 1);
444
445 if ((headers = mime_parse_hdr(asnin)) == NULL) {
446 ERR_raise(ERR_LIB_ASN1, ASN1_R_MIME_SIG_PARSE_ERROR);
447 sk_BIO_pop_free(parts, BIO_vfree);
448 return NULL;
449 }
450
451 /* Get content type */
452
453 if ((hdr = mime_hdr_find(headers, "content-type")) == NULL
454 || hdr->value == NULL) {
455 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
456 ERR_raise(ERR_LIB_ASN1, ASN1_R_NO_SIG_CONTENT_TYPE);
457 sk_BIO_pop_free(parts, BIO_vfree);
458 return NULL;
459 }
460
461 if (strcmp(hdr->value, "application/x-pkcs7-signature") &&
462 strcmp(hdr->value, "application/pkcs7-signature")) {
463 ERR_raise_data(ERR_LIB_ASN1, ASN1_R_SIG_INVALID_MIME_TYPE,
464 "type: %s", hdr->value);
465 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
466 sk_BIO_pop_free(parts, BIO_vfree);
467 return NULL;
468 }
469 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
470 /* Read in ASN1 */
471 if ((val = b64_read_asn1(asnin, it, x, libctx, propq)) == NULL) {
472 ERR_raise(ERR_LIB_ASN1, ASN1_R_ASN1_SIG_PARSE_ERROR);
473 sk_BIO_pop_free(parts, BIO_vfree);
474 return NULL;
475 }
476
477 if (bcont) {
478 *bcont = sk_BIO_value(parts, 0);
479 BIO_free(asnin);
480 sk_BIO_free(parts);
481 } else {
482 sk_BIO_pop_free(parts, BIO_vfree);
483 }
484 return val;
485 }
486
487 /* OK, if not multipart/signed try opaque signature */
488
489 if (strcmp(hdr->value, "application/x-pkcs7-mime") &&
490 strcmp(hdr->value, "application/pkcs7-mime")) {
491 ERR_raise_data(ERR_LIB_ASN1, ASN1_R_INVALID_MIME_TYPE,
492 "type: %s", hdr->value);
493 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
494 return NULL;
495 }
496
497 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
498
499 if ((val = b64_read_asn1(bio, it, x, libctx, propq)) == NULL) {
500 ERR_raise(ERR_LIB_ASN1, ASN1_R_ASN1_PARSE_ERROR);
501 return NULL;
502 }
503 return val;
504 }
505
SMIME_read_ASN1(BIO * bio,BIO ** bcont,const ASN1_ITEM * it)506 ASN1_VALUE *SMIME_read_ASN1(BIO *bio, BIO **bcont, const ASN1_ITEM *it)
507 {
508 return SMIME_read_ASN1_ex(bio, 0, bcont, it, NULL, NULL, NULL);
509 }
510
511 /* Copy text from one BIO to another making the output CRLF at EOL */
SMIME_crlf_copy(BIO * in,BIO * out,int flags)512 int SMIME_crlf_copy(BIO *in, BIO *out, int flags)
513 {
514 BIO *bf;
515 char eol;
516 int len;
517 char linebuf[MAX_SMLEN];
518 /*
519 * Buffer output so we don't write one line at a time. This is useful
520 * when streaming as we don't end up with one OCTET STRING per line.
521 */
522 bf = BIO_new(BIO_f_buffer());
523 if (bf == NULL) {
524 ERR_raise(ERR_LIB_ASN1, ERR_R_MALLOC_FAILURE);
525 return 0;
526 }
527 out = BIO_push(bf, out);
528 if (flags & SMIME_BINARY) {
529 while ((len = BIO_read(in, linebuf, MAX_SMLEN)) > 0)
530 BIO_write(out, linebuf, len);
531 } else {
532 int eolcnt = 0;
533 if (flags & SMIME_TEXT)
534 BIO_printf(out, "Content-Type: text/plain\r\n\r\n");
535 while ((len = BIO_gets(in, linebuf, MAX_SMLEN)) > 0) {
536 eol = strip_eol(linebuf, &len, flags);
537 if (len > 0) {
538 /* Not EOF: write out all CRLF */
539 if (flags & SMIME_ASCIICRLF) {
540 int i;
541 for (i = 0; i < eolcnt; i++)
542 BIO_write(out, "\r\n", 2);
543 eolcnt = 0;
544 }
545 BIO_write(out, linebuf, len);
546 if (eol)
547 BIO_write(out, "\r\n", 2);
548 } else if (flags & SMIME_ASCIICRLF) {
549 eolcnt++;
550 } else if (eol) {
551 BIO_write(out, "\r\n", 2);
552 }
553 }
554 }
555 (void)BIO_flush(out);
556 BIO_pop(out);
557 BIO_free(bf);
558 return 1;
559 }
560
561 /* Strip off headers if they are text/plain */
SMIME_text(BIO * in,BIO * out)562 int SMIME_text(BIO *in, BIO *out)
563 {
564 char iobuf[4096];
565 int len;
566 STACK_OF(MIME_HEADER) *headers;
567 MIME_HEADER *hdr;
568
569 if ((headers = mime_parse_hdr(in)) == NULL) {
570 ERR_raise(ERR_LIB_ASN1, ASN1_R_MIME_PARSE_ERROR);
571 return 0;
572 }
573 if ((hdr = mime_hdr_find(headers, "content-type")) == NULL
574 || hdr->value == NULL) {
575 ERR_raise(ERR_LIB_ASN1, ASN1_R_MIME_NO_CONTENT_TYPE);
576 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
577 return 0;
578 }
579 if (strcmp(hdr->value, "text/plain")) {
580 ERR_raise_data(ERR_LIB_ASN1, ASN1_R_INVALID_MIME_TYPE,
581 "type: %s", hdr->value);
582 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
583 return 0;
584 }
585 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
586 while ((len = BIO_read(in, iobuf, sizeof(iobuf))) > 0)
587 BIO_write(out, iobuf, len);
588 if (len < 0)
589 return 0;
590 return 1;
591 }
592
593 /*
594 * Split a multipart/XXX message body into component parts: result is
595 * canonical parts in a STACK of bios
596 */
597
multi_split(BIO * bio,int flags,const char * bound,STACK_OF (BIO)** ret)598 static int multi_split(BIO *bio, int flags, const char *bound, STACK_OF(BIO) **ret)
599 {
600 char linebuf[MAX_SMLEN];
601 int len, blen;
602 int eol = 0, next_eol = 0;
603 BIO *bpart = NULL;
604 STACK_OF(BIO) *parts;
605 char state, part, first;
606
607 blen = strlen(bound);
608 part = 0;
609 state = 0;
610 first = 1;
611 parts = sk_BIO_new_null();
612 *ret = parts;
613 if (*ret == NULL)
614 return 0;
615 while ((len = BIO_get_line(bio, linebuf, MAX_SMLEN)) > 0) {
616 state = mime_bound_check(linebuf, len, bound, blen);
617 if (state == 1) {
618 first = 1;
619 part++;
620 } else if (state == 2) {
621 if (!sk_BIO_push(parts, bpart)) {
622 BIO_free(bpart);
623 return 0;
624 }
625 return 1;
626 } else if (part != 0) {
627 /* Strip (possibly CR +) LF from linebuf */
628 next_eol = strip_eol(linebuf, &len, flags);
629 if (first) {
630 first = 0;
631 if (bpart)
632 if (!sk_BIO_push(parts, bpart)) {
633 BIO_free(bpart);
634 return 0;
635 }
636 bpart = BIO_new(BIO_s_mem());
637 if (bpart == NULL)
638 return 0;
639 BIO_set_mem_eof_return(bpart, 0);
640 } else if (eol) {
641 if (
642 #ifndef OPENSSL_NO_CMS
643 (flags & CMS_BINARY) == 0
644 #else
645 1
646 #endif
647 || (flags & SMIME_CRLFEOL) != 0)
648 BIO_write(bpart, "\r\n", 2);
649 else
650 BIO_write(bpart, "\n", 1);
651 }
652 eol = next_eol;
653 if (len > 0)
654 BIO_write(bpart, linebuf, len);
655 }
656 }
657 BIO_free(bpart);
658 return 0;
659 }
660
661 /* This is the big one: parse MIME header lines up to message body */
662
663 #define MIME_INVALID 0
664 #define MIME_START 1
665 #define MIME_TYPE 2
666 #define MIME_NAME 3
667 #define MIME_VALUE 4
668 #define MIME_QUOTE 5
669 #define MIME_COMMENT 6
670
STACK_OF(MIME_HEADER)671 static STACK_OF(MIME_HEADER) *mime_parse_hdr(BIO *bio)
672 {
673 char *p, *q, c;
674 char *ntmp;
675 char linebuf[MAX_SMLEN];
676 MIME_HEADER *mhdr = NULL, *new_hdr = NULL;
677 STACK_OF(MIME_HEADER) *headers;
678 int len, state, save_state = 0;
679
680 headers = sk_MIME_HEADER_new(mime_hdr_cmp);
681 if (headers == NULL)
682 return NULL;
683 while ((len = BIO_gets(bio, linebuf, MAX_SMLEN)) > 0) {
684 /* If whitespace at line start then continuation line */
685 if (mhdr && ossl_isspace(linebuf[0]))
686 state = MIME_NAME;
687 else
688 state = MIME_START;
689 ntmp = NULL;
690 /* Go through all characters */
691 for (p = linebuf, q = linebuf; (c = *p) && (c != '\r') && (c != '\n');
692 p++) {
693
694 /*
695 * State machine to handle MIME headers if this looks horrible
696 * that's because it *is*
697 */
698
699 switch (state) {
700 case MIME_START:
701 if (c == ':') {
702 state = MIME_TYPE;
703 *p = 0;
704 ntmp = strip_ends(q);
705 q = p + 1;
706 }
707 break;
708
709 case MIME_TYPE:
710 if (c == ';') {
711 mime_debug("Found End Value\n");
712 *p = 0;
713 new_hdr = mime_hdr_new(ntmp, strip_ends(q));
714 if (new_hdr == NULL)
715 goto err;
716 if (!sk_MIME_HEADER_push(headers, new_hdr))
717 goto err;
718 mhdr = new_hdr;
719 new_hdr = NULL;
720 ntmp = NULL;
721 q = p + 1;
722 state = MIME_NAME;
723 } else if (c == '(') {
724 save_state = state;
725 state = MIME_COMMENT;
726 }
727 break;
728
729 case MIME_COMMENT:
730 if (c == ')') {
731 state = save_state;
732 }
733 break;
734
735 case MIME_NAME:
736 if (c == '=') {
737 state = MIME_VALUE;
738 *p = 0;
739 ntmp = strip_ends(q);
740 q = p + 1;
741 }
742 break;
743
744 case MIME_VALUE:
745 if (c == ';') {
746 state = MIME_NAME;
747 *p = 0;
748 mime_hdr_addparam(mhdr, ntmp, strip_ends(q));
749 ntmp = NULL;
750 q = p + 1;
751 } else if (c == '"') {
752 mime_debug("Found Quote\n");
753 state = MIME_QUOTE;
754 } else if (c == '(') {
755 save_state = state;
756 state = MIME_COMMENT;
757 }
758 break;
759
760 case MIME_QUOTE:
761 if (c == '"') {
762 mime_debug("Found Match Quote\n");
763 state = MIME_VALUE;
764 }
765 break;
766 }
767 }
768
769 if (state == MIME_TYPE) {
770 new_hdr = mime_hdr_new(ntmp, strip_ends(q));
771 if (new_hdr == NULL)
772 goto err;
773 if (!sk_MIME_HEADER_push(headers, new_hdr))
774 goto err;
775 mhdr = new_hdr;
776 new_hdr = NULL;
777 } else if (state == MIME_VALUE) {
778 mime_hdr_addparam(mhdr, ntmp, strip_ends(q));
779 }
780 if (p == linebuf)
781 break; /* Blank line means end of headers */
782 }
783
784 return headers;
785
786 err:
787 mime_hdr_free(new_hdr);
788 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
789 return NULL;
790 }
791
strip_ends(char * name)792 static char *strip_ends(char *name)
793 {
794 return strip_end(strip_start(name));
795 }
796
797 /* Strip a parameter of whitespace from start of param */
strip_start(char * name)798 static char *strip_start(char *name)
799 {
800 char *p, c;
801 /* Look for first non whitespace or quote */
802 for (p = name; (c = *p); p++) {
803 if (c == '"') {
804 /* Next char is start of string if non null */
805 if (p[1])
806 return p + 1;
807 /* Else null string */
808 return NULL;
809 }
810 if (!ossl_isspace(c))
811 return p;
812 }
813 return NULL;
814 }
815
816 /* As above but strip from end of string : maybe should handle brackets? */
strip_end(char * name)817 static char *strip_end(char *name)
818 {
819 char *p, c;
820 if (!name)
821 return NULL;
822 /* Look for first non whitespace or quote */
823 for (p = name + strlen(name) - 1; p >= name; p--) {
824 c = *p;
825 if (c == '"') {
826 if (p - 1 == name)
827 return NULL;
828 *p = 0;
829 return name;
830 }
831 if (ossl_isspace(c))
832 *p = 0;
833 else
834 return name;
835 }
836 return NULL;
837 }
838
mime_hdr_new(const char * name,const char * value)839 static MIME_HEADER *mime_hdr_new(const char *name, const char *value)
840 {
841 MIME_HEADER *mhdr = NULL;
842 char *tmpname = NULL, *tmpval = NULL, *p;
843
844 if (name) {
845 if ((tmpname = OPENSSL_strdup(name)) == NULL)
846 return NULL;
847 for (p = tmpname; *p; p++)
848 *p = ossl_tolower(*p);
849 }
850 if (value) {
851 if ((tmpval = OPENSSL_strdup(value)) == NULL)
852 goto err;
853 for (p = tmpval; *p; p++)
854 *p = ossl_tolower(*p);
855 }
856 mhdr = OPENSSL_malloc(sizeof(*mhdr));
857 if (mhdr == NULL)
858 goto err;
859 mhdr->name = tmpname;
860 mhdr->value = tmpval;
861 if ((mhdr->params = sk_MIME_PARAM_new(mime_param_cmp)) == NULL)
862 goto err;
863 return mhdr;
864
865 err:
866 OPENSSL_free(tmpname);
867 OPENSSL_free(tmpval);
868 OPENSSL_free(mhdr);
869 return NULL;
870 }
871
mime_hdr_addparam(MIME_HEADER * mhdr,const char * name,const char * value)872 static int mime_hdr_addparam(MIME_HEADER *mhdr, const char *name, const char *value)
873 {
874 char *tmpname = NULL, *tmpval = NULL, *p;
875 MIME_PARAM *mparam = NULL;
876
877 if (name) {
878 tmpname = OPENSSL_strdup(name);
879 if (!tmpname)
880 goto err;
881 for (p = tmpname; *p; p++)
882 *p = ossl_tolower(*p);
883 }
884 if (value) {
885 tmpval = OPENSSL_strdup(value);
886 if (!tmpval)
887 goto err;
888 }
889 /* Parameter values are case sensitive so leave as is */
890 mparam = OPENSSL_malloc(sizeof(*mparam));
891 if (mparam == NULL)
892 goto err;
893 mparam->param_name = tmpname;
894 mparam->param_value = tmpval;
895 if (!sk_MIME_PARAM_push(mhdr->params, mparam))
896 goto err;
897 return 1;
898 err:
899 OPENSSL_free(tmpname);
900 OPENSSL_free(tmpval);
901 OPENSSL_free(mparam);
902 return 0;
903 }
904
mime_hdr_cmp(const MIME_HEADER * const * a,const MIME_HEADER * const * b)905 static int mime_hdr_cmp(const MIME_HEADER *const *a,
906 const MIME_HEADER *const *b)
907 {
908 if ((*a)->name == NULL || (*b)->name == NULL)
909 return ((*a)->name != NULL) - ((*b)->name != NULL);
910
911 return strcmp((*a)->name, (*b)->name);
912 }
913
mime_param_cmp(const MIME_PARAM * const * a,const MIME_PARAM * const * b)914 static int mime_param_cmp(const MIME_PARAM *const *a,
915 const MIME_PARAM *const *b)
916 {
917 if ((*a)->param_name == NULL || (*b)->param_name == NULL)
918 return ((*a)->param_name != NULL) - ((*b)->param_name != NULL);
919 return strcmp((*a)->param_name, (*b)->param_name);
920 }
921
922 /* Find a header with a given name (if possible) */
923
mime_hdr_find(STACK_OF (MIME_HEADER)* hdrs,const char * name)924 static MIME_HEADER *mime_hdr_find(STACK_OF(MIME_HEADER) *hdrs, const char *name)
925 {
926 MIME_HEADER htmp;
927 int idx;
928
929 htmp.name = (char *)name;
930 htmp.value = NULL;
931 htmp.params = NULL;
932
933 idx = sk_MIME_HEADER_find(hdrs, &htmp);
934 return sk_MIME_HEADER_value(hdrs, idx);
935 }
936
mime_param_find(MIME_HEADER * hdr,const char * name)937 static MIME_PARAM *mime_param_find(MIME_HEADER *hdr, const char *name)
938 {
939 MIME_PARAM param;
940 int idx;
941
942 param.param_name = (char *)name;
943 param.param_value = NULL;
944 idx = sk_MIME_PARAM_find(hdr->params, ¶m);
945 return sk_MIME_PARAM_value(hdr->params, idx);
946 }
947
mime_hdr_free(MIME_HEADER * hdr)948 static void mime_hdr_free(MIME_HEADER *hdr)
949 {
950 if (hdr == NULL)
951 return;
952 OPENSSL_free(hdr->name);
953 OPENSSL_free(hdr->value);
954 if (hdr->params)
955 sk_MIME_PARAM_pop_free(hdr->params, mime_param_free);
956 OPENSSL_free(hdr);
957 }
958
mime_param_free(MIME_PARAM * param)959 static void mime_param_free(MIME_PARAM *param)
960 {
961 OPENSSL_free(param->param_name);
962 OPENSSL_free(param->param_value);
963 OPENSSL_free(param);
964 }
965
966 /*-
967 * Check for a multipart boundary. Returns:
968 * 0 : no boundary
969 * 1 : part boundary
970 * 2 : final boundary
971 */
mime_bound_check(char * line,int linelen,const char * bound,int blen)972 static int mime_bound_check(char *line, int linelen, const char *bound, int blen)
973 {
974 if (linelen == -1)
975 linelen = strlen(line);
976 if (blen == -1)
977 blen = strlen(bound);
978 /* Quickly eliminate if line length too short */
979 if (blen + 2 > linelen)
980 return 0;
981 /* Check for part boundary */
982 if ((strncmp(line, "--", 2) == 0)
983 && strncmp(line + 2, bound, blen) == 0) {
984 if (strncmp(line + blen + 2, "--", 2) == 0)
985 return 2;
986 else
987 return 1;
988 }
989 return 0;
990 }
991
strip_eol(char * linebuf,int * plen,int flags)992 static int strip_eol(char *linebuf, int *plen, int flags)
993 {
994 int len = *plen;
995 char *p, c;
996 int is_eol = 0;
997
998 #ifndef OPENSSL_NO_CMS
999 if ((flags & CMS_BINARY) != 0) {
1000 if (len <= 0 || linebuf[len - 1] != '\n')
1001 return 0;
1002 if ((flags & SMIME_CRLFEOL) != 0) {
1003 if (len <= 1 || linebuf[len - 2] != '\r')
1004 return 0;
1005 len--;
1006 }
1007 len--;
1008 *plen = len;
1009 return 1;
1010 }
1011 #endif
1012
1013 for (p = linebuf + len - 1; len > 0; len--, p--) {
1014 c = *p;
1015 if (c == '\n') {
1016 is_eol = 1;
1017 } else if (is_eol && (flags & SMIME_ASCIICRLF) != 0 && c == 32) {
1018 /* Strip trailing space on a line; 32 == ASCII for ' ' */
1019 continue;
1020 } else if (c != '\r') {
1021 break;
1022 }
1023 }
1024 *plen = len;
1025 return is_eol;
1026 }
1027