1 /*
2 * Copyright 2008-2023 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_BUF_LIB);
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_BIO_LIB);
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_BIO_LIB);
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_id_smime_ct_authEnvelopedData) {
304 msg_type = "authEnveloped-data";
305 } else if (ctype_nid == NID_pkcs7_signed) {
306 if (econt_nid == NID_id_smime_ct_receipt)
307 msg_type = "signed-receipt";
308 else if (sk_X509_ALGOR_num(mdalgs) >= 0)
309 msg_type = "signed-data";
310 else
311 msg_type = "certs-only";
312 } else if (ctype_nid == NID_id_smime_ct_compressedData) {
313 msg_type = "compressed-data";
314 cname = "smime.p7z";
315 }
316 /* MIME headers */
317 BIO_printf(bio, "MIME-Version: 1.0%s", mime_eol);
318 BIO_printf(bio, "Content-Disposition: attachment;");
319 BIO_printf(bio, " filename=\"%s\"%s", cname, mime_eol);
320 BIO_printf(bio, "Content-Type: %smime;", mime_prefix);
321 if (msg_type)
322 BIO_printf(bio, " smime-type=%s;", msg_type);
323 BIO_printf(bio, " name=\"%s\"%s", cname, mime_eol);
324 BIO_printf(bio, "Content-Transfer-Encoding: base64%s%s",
325 mime_eol, mime_eol);
326 if (!B64_write_ASN1(bio, val, data, flags, it))
327 return 0;
328 BIO_printf(bio, "%s", mime_eol);
329 return 1;
330 }
331
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)332 int SMIME_write_ASN1(BIO *bio, ASN1_VALUE *val, BIO *data, int flags,
333 int ctype_nid, int econt_nid,
334 STACK_OF(X509_ALGOR) *mdalgs, const ASN1_ITEM *it)
335 {
336 return SMIME_write_ASN1_ex(bio, val, data, flags, ctype_nid, econt_nid,
337 mdalgs, it, NULL, NULL);
338 }
339
340 /* Handle output of ASN1 data */
341
342 /* cannot constify val because of CMS_dataFinal() */
asn1_output_data(BIO * out,BIO * data,ASN1_VALUE * val,int flags,const ASN1_ITEM * it)343 static int asn1_output_data(BIO *out, BIO *data, ASN1_VALUE *val, int flags,
344 const ASN1_ITEM *it)
345 {
346 BIO *tmpbio;
347 const ASN1_AUX *aux = it->funcs;
348 ASN1_STREAM_ARG sarg;
349 int rv = 1;
350
351 /*
352 * If data is not detached or resigning then the output BIO is already
353 * set up to finalise when it is written through.
354 */
355 if (!(flags & SMIME_DETACHED) || (flags & PKCS7_REUSE_DIGEST)) {
356 return SMIME_crlf_copy(data, out, flags);
357 }
358
359 if (!aux || !aux->asn1_cb) {
360 ERR_raise(ERR_LIB_ASN1, ASN1_R_STREAMING_NOT_SUPPORTED);
361 return 0;
362 }
363
364 sarg.out = out;
365 sarg.ndef_bio = NULL;
366 sarg.boundary = NULL;
367
368 /* Let ASN1 code prepend any needed BIOs */
369
370 if (aux->asn1_cb(ASN1_OP_DETACHED_PRE, &val, it, &sarg) <= 0)
371 return 0;
372
373 /* Copy data across, passing through filter BIOs for processing */
374 if (!SMIME_crlf_copy(data, sarg.ndef_bio, flags))
375 rv = 0;
376
377 /* Finalize structure */
378 if (aux->asn1_cb(ASN1_OP_DETACHED_POST, &val, it, &sarg) <= 0)
379 rv = 0;
380
381 /* Now remove any digests prepended to the BIO */
382
383 while (sarg.ndef_bio != out) {
384 tmpbio = BIO_pop(sarg.ndef_bio);
385 BIO_free(sarg.ndef_bio);
386 sarg.ndef_bio = tmpbio;
387 }
388
389 return rv;
390
391 }
392
393 /*
394 * SMIME reader: handle multipart/signed and opaque signing. in multipart
395 * case the content is placed in a memory BIO pointed to by "bcont". In
396 * opaque this is set to NULL
397 */
398
SMIME_read_ASN1_ex(BIO * bio,int flags,BIO ** bcont,const ASN1_ITEM * it,ASN1_VALUE ** x,OSSL_LIB_CTX * libctx,const char * propq)399 ASN1_VALUE *SMIME_read_ASN1_ex(BIO *bio, int flags, BIO **bcont,
400 const ASN1_ITEM *it, ASN1_VALUE **x,
401 OSSL_LIB_CTX *libctx, const char *propq)
402 {
403 BIO *asnin;
404 STACK_OF(MIME_HEADER) *headers = NULL;
405 STACK_OF(BIO) *parts = NULL;
406 MIME_HEADER *hdr;
407 MIME_PARAM *prm;
408 ASN1_VALUE *val;
409 int ret;
410
411 if (bcont)
412 *bcont = NULL;
413
414 if ((headers = mime_parse_hdr(bio)) == NULL) {
415 ERR_raise(ERR_LIB_ASN1, ASN1_R_MIME_PARSE_ERROR);
416 return NULL;
417 }
418
419 if ((hdr = mime_hdr_find(headers, "content-type")) == NULL
420 || hdr->value == NULL) {
421 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
422 ERR_raise(ERR_LIB_ASN1, ASN1_R_NO_CONTENT_TYPE);
423 return NULL;
424 }
425
426 /* Handle multipart/signed */
427
428 if (strcmp(hdr->value, "multipart/signed") == 0) {
429 /* Split into two parts */
430 prm = mime_param_find(hdr, "boundary");
431 if (prm == NULL || prm->param_value == NULL) {
432 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
433 ERR_raise(ERR_LIB_ASN1, ASN1_R_NO_MULTIPART_BOUNDARY);
434 return NULL;
435 }
436 ret = multi_split(bio, flags, prm->param_value, &parts);
437 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
438 if (!ret || (sk_BIO_num(parts) != 2)) {
439 ERR_raise(ERR_LIB_ASN1, ASN1_R_NO_MULTIPART_BODY_FAILURE);
440 sk_BIO_pop_free(parts, BIO_vfree);
441 return NULL;
442 }
443
444 /* Parse the signature piece */
445 asnin = sk_BIO_value(parts, 1);
446
447 if ((headers = mime_parse_hdr(asnin)) == NULL) {
448 ERR_raise(ERR_LIB_ASN1, ASN1_R_MIME_SIG_PARSE_ERROR);
449 sk_BIO_pop_free(parts, BIO_vfree);
450 return NULL;
451 }
452
453 /* Get content type */
454
455 if ((hdr = mime_hdr_find(headers, "content-type")) == NULL
456 || hdr->value == NULL) {
457 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
458 ERR_raise(ERR_LIB_ASN1, ASN1_R_NO_SIG_CONTENT_TYPE);
459 sk_BIO_pop_free(parts, BIO_vfree);
460 return NULL;
461 }
462
463 if (strcmp(hdr->value, "application/x-pkcs7-signature") &&
464 strcmp(hdr->value, "application/pkcs7-signature")) {
465 ERR_raise_data(ERR_LIB_ASN1, ASN1_R_SIG_INVALID_MIME_TYPE,
466 "type: %s", hdr->value);
467 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
468 sk_BIO_pop_free(parts, BIO_vfree);
469 return NULL;
470 }
471 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
472 /* Read in ASN1 */
473 if ((val = b64_read_asn1(asnin, it, x, libctx, propq)) == NULL) {
474 ERR_raise(ERR_LIB_ASN1, ASN1_R_ASN1_SIG_PARSE_ERROR);
475 sk_BIO_pop_free(parts, BIO_vfree);
476 return NULL;
477 }
478
479 if (bcont) {
480 *bcont = sk_BIO_value(parts, 0);
481 BIO_free(asnin);
482 sk_BIO_free(parts);
483 } else {
484 sk_BIO_pop_free(parts, BIO_vfree);
485 }
486 return val;
487 }
488
489 /* OK, if not multipart/signed try opaque signature */
490
491 if (strcmp(hdr->value, "application/x-pkcs7-mime") &&
492 strcmp(hdr->value, "application/pkcs7-mime")) {
493 ERR_raise_data(ERR_LIB_ASN1, ASN1_R_INVALID_MIME_TYPE,
494 "type: %s", hdr->value);
495 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
496 return NULL;
497 }
498
499 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
500
501 if ((val = b64_read_asn1(bio, it, x, libctx, propq)) == NULL) {
502 ERR_raise(ERR_LIB_ASN1, ASN1_R_ASN1_PARSE_ERROR);
503 return NULL;
504 }
505 return val;
506 }
507
SMIME_read_ASN1(BIO * bio,BIO ** bcont,const ASN1_ITEM * it)508 ASN1_VALUE *SMIME_read_ASN1(BIO *bio, BIO **bcont, const ASN1_ITEM *it)
509 {
510 return SMIME_read_ASN1_ex(bio, 0, bcont, it, NULL, NULL, NULL);
511 }
512
513 /* Copy text from one BIO to another making the output CRLF at EOL */
SMIME_crlf_copy(BIO * in,BIO * out,int flags)514 int SMIME_crlf_copy(BIO *in, BIO *out, int flags)
515 {
516 BIO *bf;
517 char eol;
518 int len;
519 char linebuf[MAX_SMLEN];
520 int ret;
521
522 if (in == NULL || out == NULL) {
523 ERR_raise(ERR_LIB_ASN1, ERR_R_PASSED_NULL_PARAMETER);
524 return 0;
525 }
526
527 /*
528 * Buffer output so we don't write one line at a time. This is useful
529 * when streaming as we don't end up with one OCTET STRING per line.
530 */
531 bf = BIO_new(BIO_f_buffer());
532 if (bf == NULL) {
533 ERR_raise(ERR_LIB_ASN1, ERR_R_BIO_LIB);
534 return 0;
535 }
536 out = BIO_push(bf, out);
537 if (flags & SMIME_BINARY) {
538 while ((len = BIO_read(in, linebuf, MAX_SMLEN)) > 0)
539 BIO_write(out, linebuf, len);
540 } else {
541 int eolcnt = 0;
542 if (flags & SMIME_TEXT)
543 BIO_printf(out, "Content-Type: text/plain\r\n\r\n");
544 while ((len = BIO_gets(in, linebuf, MAX_SMLEN)) > 0) {
545 eol = strip_eol(linebuf, &len, flags);
546 if (len > 0) {
547 /* Not EOF: write out all CRLF */
548 if (flags & SMIME_ASCIICRLF) {
549 int i;
550 for (i = 0; i < eolcnt; i++)
551 BIO_write(out, "\r\n", 2);
552 eolcnt = 0;
553 }
554 BIO_write(out, linebuf, len);
555 if (eol)
556 BIO_write(out, "\r\n", 2);
557 } else if (flags & SMIME_ASCIICRLF) {
558 eolcnt++;
559 } else if (eol) {
560 BIO_write(out, "\r\n", 2);
561 }
562 }
563 }
564 ret = BIO_flush(out);
565 BIO_pop(out);
566 BIO_free(bf);
567 if (ret <= 0)
568 return 0;
569
570 return 1;
571 }
572
573 /* Strip off headers if they are text/plain */
SMIME_text(BIO * in,BIO * out)574 int SMIME_text(BIO *in, BIO *out)
575 {
576 char iobuf[4096];
577 int len;
578 STACK_OF(MIME_HEADER) *headers;
579 MIME_HEADER *hdr;
580
581 if ((headers = mime_parse_hdr(in)) == NULL) {
582 ERR_raise(ERR_LIB_ASN1, ASN1_R_MIME_PARSE_ERROR);
583 return 0;
584 }
585 if ((hdr = mime_hdr_find(headers, "content-type")) == NULL
586 || hdr->value == NULL) {
587 ERR_raise(ERR_LIB_ASN1, ASN1_R_MIME_NO_CONTENT_TYPE);
588 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
589 return 0;
590 }
591 if (strcmp(hdr->value, "text/plain")) {
592 ERR_raise_data(ERR_LIB_ASN1, ASN1_R_INVALID_MIME_TYPE,
593 "type: %s", hdr->value);
594 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
595 return 0;
596 }
597 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
598 while ((len = BIO_read(in, iobuf, sizeof(iobuf))) > 0)
599 BIO_write(out, iobuf, len);
600 if (len < 0)
601 return 0;
602 return 1;
603 }
604
605 /*
606 * Split a multipart/XXX message body into component parts: result is
607 * canonical parts in a STACK of bios
608 */
609
multi_split(BIO * bio,int flags,const char * bound,STACK_OF (BIO)** ret)610 static int multi_split(BIO *bio, int flags, const char *bound, STACK_OF(BIO) **ret)
611 {
612 char linebuf[MAX_SMLEN];
613 int len, blen;
614 int eol = 0, next_eol = 0;
615 BIO *bpart = NULL;
616 STACK_OF(BIO) *parts;
617 char state, part, first;
618
619 blen = strlen(bound);
620 part = 0;
621 state = 0;
622 first = 1;
623 parts = sk_BIO_new_null();
624 *ret = parts;
625 if (*ret == NULL)
626 return 0;
627 while ((len = BIO_get_line(bio, linebuf, MAX_SMLEN)) > 0) {
628 state = mime_bound_check(linebuf, len, bound, blen);
629 if (state == 1) {
630 first = 1;
631 part++;
632 } else if (state == 2) {
633 if (!sk_BIO_push(parts, bpart)) {
634 BIO_free(bpart);
635 return 0;
636 }
637 return 1;
638 } else if (part != 0) {
639 /* Strip (possibly CR +) LF from linebuf */
640 next_eol = strip_eol(linebuf, &len, flags);
641 if (first) {
642 first = 0;
643 if (bpart)
644 if (!sk_BIO_push(parts, bpart)) {
645 BIO_free(bpart);
646 return 0;
647 }
648 bpart = BIO_new(BIO_s_mem());
649 if (bpart == NULL)
650 return 0;
651 BIO_set_mem_eof_return(bpart, 0);
652 } else if (eol) {
653 if (
654 #ifndef OPENSSL_NO_CMS
655 (flags & CMS_BINARY) == 0
656 #else
657 1
658 #endif
659 || (flags & SMIME_CRLFEOL) != 0)
660 BIO_write(bpart, "\r\n", 2);
661 else
662 BIO_write(bpart, "\n", 1);
663 }
664 eol = next_eol;
665 if (len > 0)
666 BIO_write(bpart, linebuf, len);
667 }
668 }
669 BIO_free(bpart);
670 return 0;
671 }
672
673 /* This is the big one: parse MIME header lines up to message body */
674
675 #define MIME_INVALID 0
676 #define MIME_START 1
677 #define MIME_TYPE 2
678 #define MIME_NAME 3
679 #define MIME_VALUE 4
680 #define MIME_QUOTE 5
681 #define MIME_COMMENT 6
682
STACK_OF(MIME_HEADER)683 static STACK_OF(MIME_HEADER) *mime_parse_hdr(BIO *bio)
684 {
685 char *p, *q, c;
686 char *ntmp;
687 char linebuf[MAX_SMLEN];
688 MIME_HEADER *mhdr = NULL, *new_hdr = NULL;
689 STACK_OF(MIME_HEADER) *headers;
690 int i, len, state, save_state = 0;
691
692 headers = sk_MIME_HEADER_new(mime_hdr_cmp);
693 if (headers == NULL)
694 return NULL;
695 while ((len = BIO_gets(bio, linebuf, MAX_SMLEN)) > 0) {
696 /* If whitespace at line start then continuation line */
697 if (mhdr && ossl_isspace(linebuf[0]))
698 state = MIME_NAME;
699 else
700 state = MIME_START;
701 ntmp = NULL;
702 /* Go through all characters */
703 for (p = linebuf, q = linebuf; (c = *p) && (c != '\r') && (c != '\n');
704 p++) {
705
706 /*
707 * State machine to handle MIME headers if this looks horrible
708 * that's because it *is*
709 */
710
711 switch (state) {
712 case MIME_START:
713 if (c == ':') {
714 state = MIME_TYPE;
715 *p = 0;
716 ntmp = strip_ends(q);
717 q = p + 1;
718 }
719 break;
720
721 case MIME_TYPE:
722 if (c == ';') {
723 mime_debug("Found End Value\n");
724 *p = 0;
725 new_hdr = mime_hdr_new(ntmp, strip_ends(q));
726 if (new_hdr == NULL)
727 goto err;
728 if (!sk_MIME_HEADER_push(headers, new_hdr))
729 goto err;
730 mhdr = new_hdr;
731 new_hdr = NULL;
732 ntmp = NULL;
733 q = p + 1;
734 state = MIME_NAME;
735 } else if (c == '(') {
736 save_state = state;
737 state = MIME_COMMENT;
738 }
739 break;
740
741 case MIME_COMMENT:
742 if (c == ')') {
743 state = save_state;
744 }
745 break;
746
747 case MIME_NAME:
748 if (c == '=') {
749 state = MIME_VALUE;
750 *p = 0;
751 ntmp = strip_ends(q);
752 q = p + 1;
753 }
754 break;
755
756 case MIME_VALUE:
757 if (c == ';') {
758 state = MIME_NAME;
759 *p = 0;
760 mime_hdr_addparam(mhdr, ntmp, strip_ends(q));
761 ntmp = NULL;
762 q = p + 1;
763 } else if (c == '"') {
764 mime_debug("Found Quote\n");
765 state = MIME_QUOTE;
766 } else if (c == '(') {
767 save_state = state;
768 state = MIME_COMMENT;
769 }
770 break;
771
772 case MIME_QUOTE:
773 if (c == '"') {
774 mime_debug("Found Match Quote\n");
775 state = MIME_VALUE;
776 }
777 break;
778 }
779 }
780
781 if (state == MIME_TYPE) {
782 new_hdr = mime_hdr_new(ntmp, strip_ends(q));
783 if (new_hdr == NULL)
784 goto err;
785 if (!sk_MIME_HEADER_push(headers, new_hdr))
786 goto err;
787 mhdr = new_hdr;
788 new_hdr = NULL;
789 } else if (state == MIME_VALUE) {
790 mime_hdr_addparam(mhdr, ntmp, strip_ends(q));
791 }
792 if (p == linebuf)
793 break; /* Blank line means end of headers */
794 }
795
796 /* Sort the headers and their params for faster searching */
797 sk_MIME_HEADER_sort(headers);
798 for (i = 0; i < sk_MIME_HEADER_num(headers); i++)
799 if ((mhdr = sk_MIME_HEADER_value(headers, i)) != NULL
800 && mhdr->params != NULL)
801 sk_MIME_PARAM_sort(mhdr->params);
802 return headers;
803
804 err:
805 mime_hdr_free(new_hdr);
806 sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
807 return NULL;
808 }
809
strip_ends(char * name)810 static char *strip_ends(char *name)
811 {
812 return strip_end(strip_start(name));
813 }
814
815 /* Strip a parameter of whitespace from start of param */
strip_start(char * name)816 static char *strip_start(char *name)
817 {
818 char *p, c;
819 /* Look for first non whitespace or quote */
820 for (p = name; (c = *p); p++) {
821 if (c == '"') {
822 /* Next char is start of string if non null */
823 if (p[1])
824 return p + 1;
825 /* Else null string */
826 return NULL;
827 }
828 if (!ossl_isspace(c))
829 return p;
830 }
831 return NULL;
832 }
833
834 /* As above but strip from end of string : maybe should handle brackets? */
strip_end(char * name)835 static char *strip_end(char *name)
836 {
837 char *p, c;
838 if (!name)
839 return NULL;
840 /* Look for first non whitespace or quote */
841 for (p = name + strlen(name) - 1; p >= name; p--) {
842 c = *p;
843 if (c == '"') {
844 if (p - 1 == name)
845 return NULL;
846 *p = 0;
847 return name;
848 }
849 if (ossl_isspace(c))
850 *p = 0;
851 else
852 return name;
853 }
854 return NULL;
855 }
856
mime_hdr_new(const char * name,const char * value)857 static MIME_HEADER *mime_hdr_new(const char *name, const char *value)
858 {
859 MIME_HEADER *mhdr = NULL;
860 char *tmpname = NULL, *tmpval = NULL, *p;
861
862 if (name) {
863 if ((tmpname = OPENSSL_strdup(name)) == NULL)
864 return NULL;
865 for (p = tmpname; *p; p++)
866 *p = ossl_tolower(*p);
867 }
868 if (value) {
869 if ((tmpval = OPENSSL_strdup(value)) == NULL)
870 goto err;
871 for (p = tmpval; *p; p++)
872 *p = ossl_tolower(*p);
873 }
874 mhdr = OPENSSL_malloc(sizeof(*mhdr));
875 if (mhdr == NULL)
876 goto err;
877 mhdr->name = tmpname;
878 mhdr->value = tmpval;
879 if ((mhdr->params = sk_MIME_PARAM_new(mime_param_cmp)) == NULL)
880 goto err;
881 return mhdr;
882
883 err:
884 OPENSSL_free(tmpname);
885 OPENSSL_free(tmpval);
886 OPENSSL_free(mhdr);
887 return NULL;
888 }
889
mime_hdr_addparam(MIME_HEADER * mhdr,const char * name,const char * value)890 static int mime_hdr_addparam(MIME_HEADER *mhdr, const char *name, const char *value)
891 {
892 char *tmpname = NULL, *tmpval = NULL, *p;
893 MIME_PARAM *mparam = NULL;
894
895 if (name) {
896 tmpname = OPENSSL_strdup(name);
897 if (!tmpname)
898 goto err;
899 for (p = tmpname; *p; p++)
900 *p = ossl_tolower(*p);
901 }
902 if (value) {
903 tmpval = OPENSSL_strdup(value);
904 if (!tmpval)
905 goto err;
906 }
907 /* Parameter values are case sensitive so leave as is */
908 mparam = OPENSSL_malloc(sizeof(*mparam));
909 if (mparam == NULL)
910 goto err;
911 mparam->param_name = tmpname;
912 mparam->param_value = tmpval;
913 if (!sk_MIME_PARAM_push(mhdr->params, mparam))
914 goto err;
915 return 1;
916 err:
917 OPENSSL_free(tmpname);
918 OPENSSL_free(tmpval);
919 OPENSSL_free(mparam);
920 return 0;
921 }
922
mime_hdr_cmp(const MIME_HEADER * const * a,const MIME_HEADER * const * b)923 static int mime_hdr_cmp(const MIME_HEADER *const *a,
924 const MIME_HEADER *const *b)
925 {
926 if ((*a)->name == NULL || (*b)->name == NULL)
927 return ((*a)->name != NULL) - ((*b)->name != NULL);
928
929 return strcmp((*a)->name, (*b)->name);
930 }
931
mime_param_cmp(const MIME_PARAM * const * a,const MIME_PARAM * const * b)932 static int mime_param_cmp(const MIME_PARAM *const *a,
933 const MIME_PARAM *const *b)
934 {
935 if ((*a)->param_name == NULL || (*b)->param_name == NULL)
936 return ((*a)->param_name != NULL) - ((*b)->param_name != NULL);
937 return strcmp((*a)->param_name, (*b)->param_name);
938 }
939
940 /* Find a header with a given name (if possible) */
941
mime_hdr_find(STACK_OF (MIME_HEADER)* hdrs,const char * name)942 static MIME_HEADER *mime_hdr_find(STACK_OF(MIME_HEADER) *hdrs, const char *name)
943 {
944 MIME_HEADER htmp;
945 int idx;
946
947 htmp.name = (char *)name;
948 htmp.value = NULL;
949 htmp.params = NULL;
950
951 idx = sk_MIME_HEADER_find(hdrs, &htmp);
952 return sk_MIME_HEADER_value(hdrs, idx);
953 }
954
mime_param_find(MIME_HEADER * hdr,const char * name)955 static MIME_PARAM *mime_param_find(MIME_HEADER *hdr, const char *name)
956 {
957 MIME_PARAM param;
958 int idx;
959
960 param.param_name = (char *)name;
961 param.param_value = NULL;
962 idx = sk_MIME_PARAM_find(hdr->params, ¶m);
963 return sk_MIME_PARAM_value(hdr->params, idx);
964 }
965
mime_hdr_free(MIME_HEADER * hdr)966 static void mime_hdr_free(MIME_HEADER *hdr)
967 {
968 if (hdr == NULL)
969 return;
970 OPENSSL_free(hdr->name);
971 OPENSSL_free(hdr->value);
972 if (hdr->params)
973 sk_MIME_PARAM_pop_free(hdr->params, mime_param_free);
974 OPENSSL_free(hdr);
975 }
976
mime_param_free(MIME_PARAM * param)977 static void mime_param_free(MIME_PARAM *param)
978 {
979 OPENSSL_free(param->param_name);
980 OPENSSL_free(param->param_value);
981 OPENSSL_free(param);
982 }
983
984 /*-
985 * Check for a multipart boundary. Returns:
986 * 0 : no boundary
987 * 1 : part boundary
988 * 2 : final boundary
989 */
mime_bound_check(char * line,int linelen,const char * bound,int blen)990 static int mime_bound_check(char *line, int linelen, const char *bound, int blen)
991 {
992 if (linelen == -1)
993 linelen = strlen(line);
994 if (blen == -1)
995 blen = strlen(bound);
996 /* Quickly eliminate if line length too short */
997 if (blen + 2 > linelen)
998 return 0;
999 /* Check for part boundary */
1000 if ((CHECK_AND_SKIP_PREFIX(line, "--")) && strncmp(line, bound, blen) == 0)
1001 return HAS_PREFIX(line + blen, "--") ? 2 : 1;
1002 return 0;
1003 }
1004
strip_eol(char * linebuf,int * plen,int flags)1005 static int strip_eol(char *linebuf, int *plen, int flags)
1006 {
1007 int len = *plen;
1008 char *p, c;
1009 int is_eol = 0;
1010
1011 #ifndef OPENSSL_NO_CMS
1012 if ((flags & CMS_BINARY) != 0) {
1013 if (len <= 0 || linebuf[len - 1] != '\n')
1014 return 0;
1015 if ((flags & SMIME_CRLFEOL) != 0) {
1016 if (len <= 1 || linebuf[len - 2] != '\r')
1017 return 0;
1018 len--;
1019 }
1020 len--;
1021 *plen = len;
1022 return 1;
1023 }
1024 #endif
1025
1026 for (p = linebuf + len - 1; len > 0; len--, p--) {
1027 c = *p;
1028 if (c == '\n') {
1029 is_eol = 1;
1030 } else if (is_eol && (flags & SMIME_ASCIICRLF) != 0 && c == 32) {
1031 /* Strip trailing space on a line; 32 == ASCII for ' ' */
1032 continue;
1033 } else if (c != '\r') {
1034 break;
1035 }
1036 }
1037 *plen = len;
1038 return is_eol;
1039 }
1040
