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