1/* pk7_mime.c */
2/* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL
3 * project 1999.
4 */
5/* ====================================================================
6 * Copyright (c) 1999-2003 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 * This product includes cryptographic software written by Eric Young
54 * (eay@cryptsoft.com).  This product includes software written by Tim
55 * Hudson (tjh@cryptsoft.com).
56 *
57 */
58
59#include <stdio.h>
60#include <ctype.h>
61#include "cryptlib.h"
62#include <openssl/rand.h>
63#include <openssl/x509.h>
64
65/* MIME and related routines */
66
67/* MIME format structures
68 * Note that all are translated to lower case apart from
69 * parameter values. Quotes are stripped off
70 */
71
72typedef struct {
73char *param_name;			/* Param name e.g. "micalg" */
74char *param_value;			/* Param value e.g. "sha1" */
75} MIME_PARAM;
76
77DECLARE_STACK_OF(MIME_PARAM)
78IMPLEMENT_STACK_OF(MIME_PARAM)
79
80typedef struct {
81char *name;				/* Name of line e.g. "content-type" */
82char *value;				/* Value of line e.g. "text/plain" */
83STACK_OF(MIME_PARAM) *params;		/* Zero or more parameters */
84} MIME_HEADER;
85
86DECLARE_STACK_OF(MIME_HEADER)
87IMPLEMENT_STACK_OF(MIME_HEADER)
88
89static int B64_write_PKCS7(BIO *bio, PKCS7 *p7);
90static PKCS7 *B64_read_PKCS7(BIO *bio);
91static char * strip_ends(char *name);
92static char * strip_start(char *name);
93static char * strip_end(char *name);
94static MIME_HEADER *mime_hdr_new(char *name, char *value);
95static int mime_hdr_addparam(MIME_HEADER *mhdr, char *name, char *value);
96static STACK_OF(MIME_HEADER) *mime_parse_hdr(BIO *bio);
97static int mime_hdr_cmp(const MIME_HEADER * const *a,
98			const MIME_HEADER * const *b);
99static int mime_param_cmp(const MIME_PARAM * const *a,
100			const MIME_PARAM * const *b);
101static void mime_param_free(MIME_PARAM *param);
102static int mime_bound_check(char *line, int linelen, char *bound, int blen);
103static int multi_split(BIO *bio, char *bound, STACK_OF(BIO) **ret);
104static int strip_eol(char *linebuf, int *plen);
105static MIME_HEADER *mime_hdr_find(STACK_OF(MIME_HEADER) *hdrs, char *name);
106static MIME_PARAM *mime_param_find(MIME_HEADER *hdr, char *name);
107static void mime_hdr_free(MIME_HEADER *hdr);
108
109#define MAX_SMLEN 1024
110#define mime_debug(x) /* x */
111
112
113typedef void (*stkfree)();
114
115/* Base 64 read and write of PKCS#7 structure */
116
117static int B64_write_PKCS7(BIO *bio, PKCS7 *p7)
118{
119	BIO *b64;
120	if(!(b64 = BIO_new(BIO_f_base64()))) {
121		PKCS7err(PKCS7_F_B64_WRITE_PKCS7,ERR_R_MALLOC_FAILURE);
122		return 0;
123	}
124	bio = BIO_push(b64, bio);
125	i2d_PKCS7_bio(bio, p7);
126	BIO_flush(bio);
127	bio = BIO_pop(bio);
128	BIO_free(b64);
129	return 1;
130}
131
132static PKCS7 *B64_read_PKCS7(BIO *bio)
133{
134	BIO *b64;
135	PKCS7 *p7;
136	if(!(b64 = BIO_new(BIO_f_base64()))) {
137		PKCS7err(PKCS7_F_B64_READ_PKCS7,ERR_R_MALLOC_FAILURE);
138		return 0;
139	}
140	bio = BIO_push(b64, bio);
141	if(!(p7 = d2i_PKCS7_bio(bio, NULL)))
142		PKCS7err(PKCS7_F_B64_READ_PKCS7,PKCS7_R_DECODE_ERROR);
143	BIO_flush(bio);
144	bio = BIO_pop(bio);
145	BIO_free(b64);
146	return p7;
147}
148
149/* SMIME sender */
150
151int SMIME_write_PKCS7(BIO *bio, PKCS7 *p7, BIO *data, int flags)
152{
153	char bound[33], c;
154	int i;
155	char *mime_prefix, *mime_eol;
156	if (flags & PKCS7_NOOLDMIMETYPE)
157		mime_prefix = "application/pkcs7-";
158	else
159		mime_prefix = "application/x-pkcs7-";
160	if (flags & PKCS7_CRLFEOL)
161		mime_eol = "\r\n";
162	else
163		mime_eol = "\n";
164	if((flags & PKCS7_DETACHED) && data) {
165	/* We want multipart/signed */
166		/* Generate a random boundary */
167		RAND_pseudo_bytes((unsigned char *)bound, 32);
168		for(i = 0; i < 32; i++) {
169			c = bound[i] & 0xf;
170			if(c < 10) c += '0';
171			else c += 'A' - 10;
172			bound[i] = c;
173		}
174		bound[32] = 0;
175		BIO_printf(bio, "MIME-Version: 1.0%s", mime_eol);
176		BIO_printf(bio, "Content-Type: multipart/signed;");
177		BIO_printf(bio, " protocol=\"%ssignature\";", mime_prefix);
178		BIO_printf(bio, " micalg=sha1; boundary=\"----%s\"%s%s",
179						bound, mime_eol, mime_eol);
180		BIO_printf(bio, "This is an S/MIME signed message%s%s",
181						mime_eol, mime_eol);
182		/* Now write out the first part */
183		BIO_printf(bio, "------%s%s", bound, mime_eol);
184		SMIME_crlf_copy(data, bio, flags);
185		BIO_printf(bio, "%s------%s%s", mime_eol, bound, mime_eol);
186
187		/* Headers for signature */
188
189		BIO_printf(bio, "Content-Type: %ssignature;", mime_prefix);
190		BIO_printf(bio, " name=\"smime.p7s\"%s", mime_eol);
191		BIO_printf(bio, "Content-Transfer-Encoding: base64%s",
192								mime_eol);
193		BIO_printf(bio, "Content-Disposition: attachment;");
194		BIO_printf(bio, " filename=\"smime.p7s\"%s%s",
195							mime_eol, mime_eol);
196		B64_write_PKCS7(bio, p7);
197		BIO_printf(bio,"%s------%s--%s%s", mime_eol, bound,
198						mime_eol, mime_eol);
199		return 1;
200	}
201	/* MIME headers */
202	BIO_printf(bio, "MIME-Version: 1.0%s", mime_eol);
203	BIO_printf(bio, "Content-Disposition: attachment;");
204	BIO_printf(bio, " filename=\"smime.p7m\"%s", mime_eol);
205	BIO_printf(bio, "Content-Type: %smime;", mime_prefix);
206	BIO_printf(bio, " name=\"smime.p7m\"%s", mime_eol);
207	BIO_printf(bio, "Content-Transfer-Encoding: base64%s%s",
208						mime_eol, mime_eol);
209	B64_write_PKCS7(bio, p7);
210	BIO_printf(bio, "%s", mime_eol);
211	return 1;
212}
213
214/* SMIME reader: handle multipart/signed and opaque signing.
215 * in multipart case the content is placed in a memory BIO
216 * pointed to by "bcont". In opaque this is set to NULL
217 */
218
219PKCS7 *SMIME_read_PKCS7(BIO *bio, BIO **bcont)
220{
221	BIO *p7in;
222	STACK_OF(MIME_HEADER) *headers = NULL;
223	STACK_OF(BIO) *parts = NULL;
224	MIME_HEADER *hdr;
225	MIME_PARAM *prm;
226	PKCS7 *p7;
227	int ret;
228
229	if(bcont) *bcont = NULL;
230
231	if (!(headers = mime_parse_hdr(bio))) {
232		PKCS7err(PKCS7_F_SMIME_READ_PKCS7,PKCS7_R_MIME_PARSE_ERROR);
233		return NULL;
234	}
235
236	if(!(hdr = mime_hdr_find(headers, "content-type")) || !hdr->value) {
237		sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
238		PKCS7err(PKCS7_F_SMIME_READ_PKCS7, PKCS7_R_NO_CONTENT_TYPE);
239		return NULL;
240	}
241
242	/* Handle multipart/signed */
243
244	if(!strcmp(hdr->value, "multipart/signed")) {
245		/* Split into two parts */
246		prm = mime_param_find(hdr, "boundary");
247		if(!prm || !prm->param_value) {
248			sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
249			PKCS7err(PKCS7_F_SMIME_READ_PKCS7, PKCS7_R_NO_MULTIPART_BOUNDARY);
250			return NULL;
251		}
252		ret = multi_split(bio, prm->param_value, &parts);
253		sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
254		if(!ret || (sk_BIO_num(parts) != 2) ) {
255			PKCS7err(PKCS7_F_SMIME_READ_PKCS7, PKCS7_R_NO_MULTIPART_BODY_FAILURE);
256			sk_BIO_pop_free(parts, BIO_vfree);
257			return NULL;
258		}
259
260		/* Parse the signature piece */
261		p7in = sk_BIO_value(parts, 1);
262
263		if (!(headers = mime_parse_hdr(p7in))) {
264			PKCS7err(PKCS7_F_SMIME_READ_PKCS7,PKCS7_R_MIME_SIG_PARSE_ERROR);
265			sk_BIO_pop_free(parts, BIO_vfree);
266			return NULL;
267		}
268
269		/* Get content type */
270
271		if(!(hdr = mime_hdr_find(headers, "content-type")) ||
272								 !hdr->value) {
273			sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
274			PKCS7err(PKCS7_F_SMIME_READ_PKCS7, PKCS7_R_NO_SIG_CONTENT_TYPE);
275			return NULL;
276		}
277
278		if(strcmp(hdr->value, "application/x-pkcs7-signature") &&
279			strcmp(hdr->value, "application/pkcs7-signature")) {
280			sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
281			PKCS7err(PKCS7_F_SMIME_READ_PKCS7,PKCS7_R_SIG_INVALID_MIME_TYPE);
282			ERR_add_error_data(2, "type: ", hdr->value);
283			sk_BIO_pop_free(parts, BIO_vfree);
284			return NULL;
285		}
286		sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
287		/* Read in PKCS#7 */
288		if(!(p7 = B64_read_PKCS7(p7in))) {
289			PKCS7err(PKCS7_F_SMIME_READ_PKCS7,PKCS7_R_PKCS7_SIG_PARSE_ERROR);
290			sk_BIO_pop_free(parts, BIO_vfree);
291			return NULL;
292		}
293
294		if(bcont) {
295			*bcont = sk_BIO_value(parts, 0);
296			BIO_free(p7in);
297			sk_BIO_free(parts);
298		} else sk_BIO_pop_free(parts, BIO_vfree);
299		return p7;
300	}
301
302	/* OK, if not multipart/signed try opaque signature */
303
304	if (strcmp (hdr->value, "application/x-pkcs7-mime") &&
305	    strcmp (hdr->value, "application/pkcs7-mime")) {
306		PKCS7err(PKCS7_F_SMIME_READ_PKCS7,PKCS7_R_INVALID_MIME_TYPE);
307		ERR_add_error_data(2, "type: ", hdr->value);
308		sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
309		return NULL;
310	}
311
312	sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
313
314	if(!(p7 = B64_read_PKCS7(bio))) {
315		PKCS7err(PKCS7_F_SMIME_READ_PKCS7, PKCS7_R_PKCS7_PARSE_ERROR);
316		return NULL;
317	}
318	return p7;
319
320}
321
322/* Copy text from one BIO to another making the output CRLF at EOL */
323int SMIME_crlf_copy(BIO *in, BIO *out, int flags)
324{
325	char eol;
326	int len;
327	char linebuf[MAX_SMLEN];
328	if(flags & PKCS7_BINARY) {
329		while((len = BIO_read(in, linebuf, MAX_SMLEN)) > 0)
330						BIO_write(out, linebuf, len);
331		return 1;
332	}
333	if(flags & PKCS7_TEXT) BIO_printf(out, "Content-Type: text/plain\r\n\r\n");
334	while ((len = BIO_gets(in, linebuf, MAX_SMLEN)) > 0) {
335		eol = strip_eol(linebuf, &len);
336		if (len)
337			BIO_write(out, linebuf, len);
338		if(eol) BIO_write(out, "\r\n", 2);
339	}
340	return 1;
341}
342
343/* Strip off headers if they are text/plain */
344int SMIME_text(BIO *in, BIO *out)
345{
346	char iobuf[4096];
347	int len;
348	STACK_OF(MIME_HEADER) *headers;
349	MIME_HEADER *hdr;
350
351	if (!(headers = mime_parse_hdr(in))) {
352		PKCS7err(PKCS7_F_SMIME_TEXT,PKCS7_R_MIME_PARSE_ERROR);
353		return 0;
354	}
355	if(!(hdr = mime_hdr_find(headers, "content-type")) || !hdr->value) {
356		PKCS7err(PKCS7_F_SMIME_TEXT,PKCS7_R_MIME_NO_CONTENT_TYPE);
357		sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
358		return 0;
359	}
360	if (strcmp (hdr->value, "text/plain")) {
361		PKCS7err(PKCS7_F_SMIME_TEXT,PKCS7_R_INVALID_MIME_TYPE);
362		ERR_add_error_data(2, "type: ", hdr->value);
363		sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
364		return 0;
365	}
366	sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
367	while ((len = BIO_read(in, iobuf, sizeof(iobuf))) > 0)
368						BIO_write(out, iobuf, len);
369	return 1;
370}
371
372/* Split a multipart/XXX message body into component parts: result is
373 * canonical parts in a STACK of bios
374 */
375
376static int multi_split(BIO *bio, char *bound, STACK_OF(BIO) **ret)
377{
378	char linebuf[MAX_SMLEN];
379	int len, blen;
380	int eol = 0, next_eol = 0;
381	BIO *bpart = NULL;
382	STACK_OF(BIO) *parts;
383	char state, part, first;
384
385	blen = strlen(bound);
386	part = 0;
387	state = 0;
388	first = 1;
389	parts = sk_BIO_new_null();
390	*ret = parts;
391	while ((len = BIO_gets(bio, linebuf, MAX_SMLEN)) > 0) {
392		state = mime_bound_check(linebuf, len, bound, blen);
393		if(state == 1) {
394			first = 1;
395			part++;
396		} else if(state == 2) {
397			sk_BIO_push(parts, bpart);
398			return 1;
399		} else if(part) {
400			/* Strip CR+LF from linebuf */
401			next_eol = strip_eol(linebuf, &len);
402			if(first) {
403				first = 0;
404				if(bpart) sk_BIO_push(parts, bpart);
405				bpart = BIO_new(BIO_s_mem());
406				BIO_set_mem_eof_return(bpart, 0);
407			} else if (eol)
408				BIO_write(bpart, "\r\n", 2);
409			eol = next_eol;
410			if (len)
411				BIO_write(bpart, linebuf, len);
412		}
413	}
414	return 0;
415}
416
417/* This is the big one: parse MIME header lines up to message body */
418
419#define MIME_INVALID	0
420#define MIME_START	1
421#define MIME_TYPE	2
422#define MIME_NAME	3
423#define MIME_VALUE	4
424#define MIME_QUOTE	5
425#define MIME_COMMENT	6
426
427
428static STACK_OF(MIME_HEADER) *mime_parse_hdr(BIO *bio)
429{
430	char *p, *q, c;
431	char *ntmp;
432	char linebuf[MAX_SMLEN];
433	MIME_HEADER *mhdr = NULL;
434	STACK_OF(MIME_HEADER) *headers;
435	int len, state, save_state = 0;
436
437	headers = sk_MIME_HEADER_new(mime_hdr_cmp);
438	while ((len = BIO_gets(bio, linebuf, MAX_SMLEN)) > 0) {
439	/* If whitespace at line start then continuation line */
440	if(mhdr && isspace((unsigned char)linebuf[0])) state = MIME_NAME;
441	else state = MIME_START;
442	ntmp = NULL;
443	/* Go through all characters */
444	for(p = linebuf, q = linebuf; (c = *p) && (c!='\r') && (c!='\n'); p++) {
445
446	/* State machine to handle MIME headers
447	 * if this looks horrible that's because it *is*
448         */
449
450		switch(state) {
451			case MIME_START:
452			if(c == ':') {
453				state = MIME_TYPE;
454				*p = 0;
455				ntmp = strip_ends(q);
456				q = p + 1;
457			}
458			break;
459
460			case MIME_TYPE:
461			if(c == ';') {
462				mime_debug("Found End Value\n");
463				*p = 0;
464				mhdr = mime_hdr_new(ntmp, strip_ends(q));
465				sk_MIME_HEADER_push(headers, mhdr);
466				ntmp = NULL;
467				q = p + 1;
468				state = MIME_NAME;
469			} else if(c == '(') {
470				save_state = state;
471				state = MIME_COMMENT;
472			}
473			break;
474
475			case MIME_COMMENT:
476			if(c == ')') {
477				state = save_state;
478			}
479			break;
480
481			case MIME_NAME:
482			if(c == '=') {
483				state = MIME_VALUE;
484				*p = 0;
485				ntmp = strip_ends(q);
486				q = p + 1;
487			}
488			break ;
489
490			case MIME_VALUE:
491			if(c == ';') {
492				state = MIME_NAME;
493				*p = 0;
494				mime_hdr_addparam(mhdr, ntmp, strip_ends(q));
495				ntmp = NULL;
496				q = p + 1;
497			} else if (c == '"') {
498				mime_debug("Found Quote\n");
499				state = MIME_QUOTE;
500			} else if(c == '(') {
501				save_state = state;
502				state = MIME_COMMENT;
503			}
504			break;
505
506			case MIME_QUOTE:
507			if(c == '"') {
508				mime_debug("Found Match Quote\n");
509				state = MIME_VALUE;
510			}
511			break;
512		}
513	}
514
515	if(state == MIME_TYPE) {
516		mhdr = mime_hdr_new(ntmp, strip_ends(q));
517		sk_MIME_HEADER_push(headers, mhdr);
518	} else if(state == MIME_VALUE)
519			 mime_hdr_addparam(mhdr, ntmp, strip_ends(q));
520	if(p == linebuf) break;	/* Blank line means end of headers */
521}
522
523return headers;
524
525}
526
527static char *strip_ends(char *name)
528{
529	return strip_end(strip_start(name));
530}
531
532/* Strip a parameter of whitespace from start of param */
533static char *strip_start(char *name)
534{
535	char *p, c;
536	/* Look for first non white space or quote */
537	for(p = name; (c = *p) ;p++) {
538		if(c == '"') {
539			/* Next char is start of string if non null */
540			if(p[1]) return p + 1;
541			/* Else null string */
542			return NULL;
543		}
544		if(!isspace((unsigned char)c)) return p;
545	}
546	return NULL;
547}
548
549/* As above but strip from end of string : maybe should handle brackets? */
550static char *strip_end(char *name)
551{
552	char *p, c;
553	if(!name) return NULL;
554	/* Look for first non white space or quote */
555	for(p = name + strlen(name) - 1; p >= name ;p--) {
556		c = *p;
557		if(c == '"') {
558			if(p - 1 == name) return NULL;
559			*p = 0;
560			return name;
561		}
562		if(isspace((unsigned char)c)) *p = 0;
563		else return name;
564	}
565	return NULL;
566}
567
568static MIME_HEADER *mime_hdr_new(char *name, char *value)
569{
570	MIME_HEADER *mhdr;
571	char *tmpname, *tmpval, *p;
572	int c;
573	if(name) {
574		if(!(tmpname = BUF_strdup(name))) return NULL;
575		for(p = tmpname ; *p; p++) {
576			c = *p;
577			if(isupper(c)) {
578				c = tolower(c);
579				*p = c;
580			}
581		}
582	} else tmpname = NULL;
583	if(value) {
584		if(!(tmpval = BUF_strdup(value))) return NULL;
585		for(p = tmpval ; *p; p++) {
586			c = *p;
587			if(isupper(c)) {
588				c = tolower(c);
589				*p = c;
590			}
591		}
592	} else tmpval = NULL;
593	mhdr = (MIME_HEADER *) OPENSSL_malloc(sizeof(MIME_HEADER));
594	if(!mhdr) return NULL;
595	mhdr->name = tmpname;
596	mhdr->value = tmpval;
597	if(!(mhdr->params = sk_MIME_PARAM_new(mime_param_cmp))) return NULL;
598	return mhdr;
599}
600
601static int mime_hdr_addparam(MIME_HEADER *mhdr, char *name, char *value)
602{
603	char *tmpname, *tmpval, *p;
604	int c;
605	MIME_PARAM *mparam;
606	if(name) {
607		tmpname = BUF_strdup(name);
608		if(!tmpname) return 0;
609		for(p = tmpname ; *p; p++) {
610			c = *p;
611			if(isupper(c)) {
612				c = tolower(c);
613				*p = c;
614			}
615		}
616	} else tmpname = NULL;
617	if(value) {
618		tmpval = BUF_strdup(value);
619		if(!tmpval) return 0;
620	} else tmpval = NULL;
621	/* Parameter values are case sensitive so leave as is */
622	mparam = (MIME_PARAM *) OPENSSL_malloc(sizeof(MIME_PARAM));
623	if(!mparam) return 0;
624	mparam->param_name = tmpname;
625	mparam->param_value = tmpval;
626	sk_MIME_PARAM_push(mhdr->params, mparam);
627	return 1;
628}
629
630static int mime_hdr_cmp(const MIME_HEADER * const *a,
631			const MIME_HEADER * const *b)
632{
633	return(strcmp((*a)->name, (*b)->name));
634}
635
636static int mime_param_cmp(const MIME_PARAM * const *a,
637			const MIME_PARAM * const *b)
638{
639	return(strcmp((*a)->param_name, (*b)->param_name));
640}
641
642/* Find a header with a given name (if possible) */
643
644static MIME_HEADER *mime_hdr_find(STACK_OF(MIME_HEADER) *hdrs, char *name)
645{
646	MIME_HEADER htmp;
647	int idx;
648	htmp.name = name;
649	idx = sk_MIME_HEADER_find(hdrs, &htmp);
650	if(idx < 0) return NULL;
651	return sk_MIME_HEADER_value(hdrs, idx);
652}
653
654static MIME_PARAM *mime_param_find(MIME_HEADER *hdr, char *name)
655{
656	MIME_PARAM param;
657	int idx;
658	param.param_name = name;
659	idx = sk_MIME_PARAM_find(hdr->params, &param);
660	if(idx < 0) return NULL;
661	return sk_MIME_PARAM_value(hdr->params, idx);
662}
663
664static void mime_hdr_free(MIME_HEADER *hdr)
665{
666	if(hdr->name) OPENSSL_free(hdr->name);
667	if(hdr->value) OPENSSL_free(hdr->value);
668	if(hdr->params) sk_MIME_PARAM_pop_free(hdr->params, mime_param_free);
669	OPENSSL_free(hdr);
670}
671
672static void mime_param_free(MIME_PARAM *param)
673{
674	if(param->param_name) OPENSSL_free(param->param_name);
675	if(param->param_value) OPENSSL_free(param->param_value);
676	OPENSSL_free(param);
677}
678
679/* Check for a multipart boundary. Returns:
680 * 0 : no boundary
681 * 1 : part boundary
682 * 2 : final boundary
683 */
684static int mime_bound_check(char *line, int linelen, char *bound, int blen)
685{
686	if(linelen == -1) linelen = strlen(line);
687	if(blen == -1) blen = strlen(bound);
688	/* Quickly eliminate if line length too short */
689	if(blen + 2 > linelen) return 0;
690	/* Check for part boundary */
691	if(!strncmp(line, "--", 2) && !strncmp(line + 2, bound, blen)) {
692		if(!strncmp(line + blen + 2, "--", 2)) return 2;
693		else return 1;
694	}
695	return 0;
696}
697
698static int strip_eol(char *linebuf, int *plen)
699	{
700	int len = *plen;
701	char *p, c;
702	int is_eol = 0;
703	p = linebuf + len - 1;
704	for (p = linebuf + len - 1; len > 0; len--, p--)
705		{
706		c = *p;
707		if (c == '\n')
708			is_eol = 1;
709		else if (c != '\r')
710			break;
711		}
712	*plen = len;
713	return is_eol;
714	}
715