/* pk7_mime.c */

/* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL

 * project.

 */

/* ====================================================================

 * Copyright (c) 1999-2005 The OpenSSL Project.  All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer. 

 *

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in

 *    the documentation and/or other materials provided with the

 *    distribution.

 *

 * 3. All advertising materials mentioning features or use of this

 *    software must display the following acknowledgment:

 *    "This product includes software developed by the OpenSSL Project

 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"

 *

 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to

 *    endorse or promote products derived from this software without

 *    prior written permission. For written permission, please contact

 *    licensing@OpenSSL.org.

 *

 * 5. Products derived from this software may not be called "OpenSSL"

 *    nor may "OpenSSL" appear in their names without prior written

 *    permission of the OpenSSL Project.

 *

 * 6. Redistributions of any form whatsoever must retain the following

 *    acknowledgment:

 *    "This product includes software developed by the OpenSSL Project

 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"

 *

 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY

 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR

 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT

 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,

 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED

 * OF THE POSSIBILITY OF SUCH DAMAGE.

 * ====================================================================

 *

 * This product includes cryptographic software written by Eric Young

 * (eay@cryptsoft.com).  This product includes software written by Tim

 * Hudson (tjh@cryptsoft.com).

 *

 */

/*

 © Portions copyright (c) 2006 Nokia Corporation.  All rights reserved.

 */

#include <stdio.h>

#include <ctype.h>

#include "cryptlib.h"

#include <openssl/rand.h>

#include <openssl/x509.h>

/* MIME and related routines */

/* MIME format structures

 * Note that all are translated to lower case apart from

 * parameter values. Quotes are stripped off

 */

typedef struct {

char *param_name;			/* Param name e.g. "micalg" */

char *param_value;			/* Param value e.g. "sha1" */

} MIME_PARAM;

DECLARE_STACK_OF(MIME_PARAM)

IMPLEMENT_STACK_OF(MIME_PARAM)

typedef struct {

char *name;				/* Name of line e.g. "content-type" */

char *value;				/* Value of line e.g. "text/plain" */

STACK_OF(MIME_PARAM) *params;		/* Zero or more parameters */

} MIME_HEADER;

DECLARE_STACK_OF(MIME_HEADER)

IMPLEMENT_STACK_OF(MIME_HEADER)

static int pkcs7_output_data(BIO *bio, BIO *data, PKCS7 *p7, int flags);

static int B64_write_PKCS7(BIO *bio, PKCS7 *p7);

static PKCS7 *B64_read_PKCS7(BIO *bio);

static char * strip_ends(char *name);

static char * strip_start(char *name);

static char * strip_end(char *name);

static MIME_HEADER *mime_hdr_new(char *name, char *value);

static int mime_hdr_addparam(MIME_HEADER *mhdr, char *name, char *value);

static STACK_OF(MIME_HEADER) *mime_parse_hdr(BIO *bio);

static int mime_hdr_cmp(const MIME_HEADER * const *a,

			const MIME_HEADER * const *b);

static int mime_param_cmp(const MIME_PARAM * const *a,

			const MIME_PARAM * const *b);

static void mime_param_free(MIME_PARAM *param);

static int mime_bound_check(char *line, int linelen, char *bound, int blen);

static int multi_split(BIO *bio, char *bound, STACK_OF(BIO) **ret);

static int strip_eol(char *linebuf, int *plen);

static MIME_HEADER *mime_hdr_find(STACK_OF(MIME_HEADER) *hdrs, char *name);

static MIME_PARAM *mime_param_find(MIME_HEADER *hdr, char *name);

static void mime_hdr_free(MIME_HEADER *hdr);

#define MAX_SMLEN 1024

#define mime_debug(x) /* x */

/* Base 64 read and write of PKCS#7 structure */

static int B64_write_PKCS7(BIO *bio, PKCS7 *p7)

{

	BIO *b64;

	if(!(b64 = BIO_new(BIO_f_base64()))) {

		PKCS7err(PKCS7_F_B64_WRITE_PKCS7,ERR_R_MALLOC_FAILURE);

		return 0;

	}

	bio = BIO_push(b64, bio);

	i2d_PKCS7_bio(bio, p7);

	(void)BIO_flush(bio);

	bio = BIO_pop(bio);

	BIO_free(b64);

	return 1;

}

static PKCS7 *B64_read_PKCS7(BIO *bio)

{

	BIO *b64;

	PKCS7 *p7;

	if(!(b64 = BIO_new(BIO_f_base64()))) {

		PKCS7err(PKCS7_F_B64_READ_PKCS7,ERR_R_MALLOC_FAILURE);

		return 0;

	}

	bio = BIO_push(b64, bio);

	if(!(p7 = d2i_PKCS7_bio(bio, NULL))) 

		PKCS7err(PKCS7_F_B64_READ_PKCS7,PKCS7_R_DECODE_ERROR);

	(void)BIO_flush(bio);

	bio = BIO_pop(bio);

	BIO_free(b64);

	return p7;

}

/* SMIME sender */

EXPORT_C int SMIME_write_PKCS7(BIO *bio, PKCS7 *p7, BIO *data, int flags)

{

	char bound[33], c;

	int i;

	char *mime_prefix, *mime_eol, *msg_type=NULL;

	if (flags & PKCS7_NOOLDMIMETYPE)

		mime_prefix = "application/pkcs7-";

	else

		mime_prefix = "application/x-pkcs7-";

	if (flags & PKCS7_CRLFEOL)

		mime_eol = "\r\n";

	else

		mime_eol = "\n";

	if((flags & PKCS7_DETACHED) && data) {

	/* We want multipart/signed */

		/* Generate a random boundary */

		RAND_pseudo_bytes((unsigned char *)bound, 32);

		for(i = 0; i < 32; i++) {

			c = bound[i] & 0xf;

			if(c < 10) c += '0';

			else c += 'A' - 10;

			bound[i] = c;

		}

		bound[32] = 0;

		BIO_printf(bio, "MIME-Version: 1.0%s", mime_eol);

		BIO_printf(bio, "Content-Type: multipart/signed;");

		BIO_printf(bio, " protocol=\"%ssignature\";", mime_prefix);

		BIO_printf(bio, " micalg=sha1; boundary=\"----%s\"%s%s",

						bound, mime_eol, mime_eol);

		BIO_printf(bio, "This is an S/MIME signed message%s%s",

						mime_eol, mime_eol);

		/* Now write out the first part */

		BIO_printf(bio, "------%s%s", bound, mime_eol);

		pkcs7_output_data(bio, data, p7, flags);

		BIO_printf(bio, "%s------%s%s", mime_eol, bound, mime_eol);

		/* Headers for signature */

		BIO_printf(bio, "Content-Type: %ssignature;", mime_prefix); 

		BIO_printf(bio, " name=\"smime.p7s\"%s", mime_eol);

		BIO_printf(bio, "Content-Transfer-Encoding: base64%s",

								mime_eol);

		BIO_printf(bio, "Content-Disposition: attachment;");

		BIO_printf(bio, " filename=\"smime.p7s\"%s%s",

							mime_eol, mime_eol);

		B64_write_PKCS7(bio, p7);

		BIO_printf(bio,"%s------%s--%s%s", mime_eol, bound,

							mime_eol, mime_eol);

		return 1;

	}

	/* Determine smime-type header */

	if (PKCS7_type_is_enveloped(p7))

		msg_type = "enveloped-data";

	else if (PKCS7_type_is_signed(p7))

		{

		/* If we have any signers it is signed-data othewise 

		 * certs-only.

		 */

		STACK_OF(PKCS7_SIGNER_INFO) *sinfos;

		sinfos = PKCS7_get_signer_info(p7);

		if (sk_PKCS7_SIGNER_INFO_num(sinfos) > 0)

			msg_type = "signed-data";

		else

			msg_type = "certs-only";

		}

	/* MIME headers */

	BIO_printf(bio, "MIME-Version: 1.0%s", mime_eol);

	BIO_printf(bio, "Content-Disposition: attachment;");

	BIO_printf(bio, " filename=\"smime.p7m\"%s", mime_eol);

	BIO_printf(bio, "Content-Type: %smime;", mime_prefix);

	if (msg_type)

		BIO_printf(bio, " smime-type=%s;", msg_type);

	BIO_printf(bio, " name=\"smime.p7m\"%s", mime_eol);

	BIO_printf(bio, "Content-Transfer-Encoding: base64%s%s",

						mime_eol, mime_eol);

	B64_write_PKCS7(bio, p7);

	BIO_printf(bio, "%s", mime_eol);

	return 1;

}

/* Handle output of PKCS#7 data */

static int pkcs7_output_data(BIO *out, BIO *data, PKCS7 *p7, int flags)

	{

	BIO *tmpbio, *p7bio;

	if (!(flags & PKCS7_STREAM))

		{

		SMIME_crlf_copy(data, out, flags);

		return 1;

		}

	/* Partial sign operation */

	/* Initialize sign operation */

	p7bio = PKCS7_dataInit(p7, out);

	/* Copy data across, computing digests etc */

	SMIME_crlf_copy(data, p7bio, flags);

	/* Must be detached */

	PKCS7_set_detached(p7, 1);

	/* Finalize signatures */

	PKCS7_dataFinal(p7, p7bio);

	/* Now remove any digests prepended to the BIO */

	while (p7bio != out)

		{

		tmpbio = BIO_pop(p7bio);

		BIO_free(p7bio);

		p7bio = tmpbio;

		}

	return 1;

	}

/* SMIME reader: handle multipart/signed and opaque signing.

 * in multipart case the content is placed in a memory BIO

 * pointed to by "bcont". In opaque this is set to NULL

 */

EXPORT_C PKCS7 *SMIME_read_PKCS7(BIO *bio, BIO **bcont)

{

	BIO *p7in;

	STACK_OF(MIME_HEADER) *headers = NULL;

	STACK_OF(BIO) *parts = NULL;

	MIME_HEADER *hdr;

	MIME_PARAM *prm;

	PKCS7 *p7;

	int ret;

	if(bcont) *bcont = NULL;

	if (!(headers = mime_parse_hdr(bio))) {

		PKCS7err(PKCS7_F_SMIME_READ_PKCS7,PKCS7_R_MIME_PARSE_ERROR);

		return NULL;

	}

	if(!(hdr = mime_hdr_find(headers, "content-type")) || !hdr->value) {

		sk_MIME_HEADER_pop_free(headers, mime_hdr_free);

		PKCS7err(PKCS7_F_SMIME_READ_PKCS7, PKCS7_R_NO_CONTENT_TYPE);

		return NULL;

	}

	/* Handle multipart/signed */

	if(!strcmp(hdr->value, "multipart/signed")) {

		/* Split into two parts */

		prm = mime_param_find(hdr, "boundary");

		if(!prm || !prm->param_value) {

			sk_MIME_HEADER_pop_free(headers, mime_hdr_free);

			PKCS7err(PKCS7_F_SMIME_READ_PKCS7, PKCS7_R_NO_MULTIPART_BOUNDARY);

			return NULL;

		}

		ret = multi_split(bio, prm->param_value, &parts);

		sk_MIME_HEADER_pop_free(headers, mime_hdr_free);

		if(!ret || (sk_BIO_num(parts) != 2) ) {

			PKCS7err(PKCS7_F_SMIME_READ_PKCS7, PKCS7_R_NO_MULTIPART_BODY_FAILURE);

			sk_BIO_pop_free(parts, BIO_vfree);

			return NULL;

		}

		/* Parse the signature piece */

		p7in = sk_BIO_value(parts, 1);

		if (!(headers = mime_parse_hdr(p7in))) {

			PKCS7err(PKCS7_F_SMIME_READ_PKCS7,PKCS7_R_MIME_SIG_PARSE_ERROR);

			sk_BIO_pop_free(parts, BIO_vfree);

			return NULL;

		}

		/* Get content type */

		if(!(hdr = mime_hdr_find(headers, "content-type")) ||

								 !hdr->value) {

			sk_MIME_HEADER_pop_free(headers, mime_hdr_free);

			PKCS7err(PKCS7_F_SMIME_READ_PKCS7, PKCS7_R_NO_SIG_CONTENT_TYPE);

			return NULL;

		}

		if(strcmp(hdr->value, "application/x-pkcs7-signature") &&

			strcmp(hdr->value, "application/pkcs7-signature")) {

			sk_MIME_HEADER_pop_free(headers, mime_hdr_free);

			PKCS7err(PKCS7_F_SMIME_READ_PKCS7,PKCS7_R_SIG_INVALID_MIME_TYPE);

			ERR_add_error_data(2, "type: ", hdr->value);

			sk_BIO_pop_free(parts, BIO_vfree);

			return NULL;

		}

		sk_MIME_HEADER_pop_free(headers, mime_hdr_free);

		/* Read in PKCS#7 */

		if(!(p7 = B64_read_PKCS7(p7in))) {

			PKCS7err(PKCS7_F_SMIME_READ_PKCS7,PKCS7_R_PKCS7_SIG_PARSE_ERROR);

			sk_BIO_pop_free(parts, BIO_vfree);

			return NULL;

		}

		if(bcont) {

			*bcont = sk_BIO_value(parts, 0);

			BIO_free(p7in);

			sk_BIO_free(parts);

		} else sk_BIO_pop_free(parts, BIO_vfree);

		return p7;

	}

	/* OK, if not multipart/signed try opaque signature */

	if (strcmp (hdr->value, "application/x-pkcs7-mime") &&

	    strcmp (hdr->value, "application/pkcs7-mime")) {

		PKCS7err(PKCS7_F_SMIME_READ_PKCS7,PKCS7_R_INVALID_MIME_TYPE);

		ERR_add_error_data(2, "type: ", hdr->value);

		sk_MIME_HEADER_pop_free(headers, mime_hdr_free);

		return NULL;

	}

	sk_MIME_HEADER_pop_free(headers, mime_hdr_free);

	if(!(p7 = B64_read_PKCS7(bio))) {

		PKCS7err(PKCS7_F_SMIME_READ_PKCS7, PKCS7_R_PKCS7_PARSE_ERROR);

		return NULL;

	}

	return p7;

}

/* Copy text from one BIO to another making the output CRLF at EOL */

EXPORT_C int SMIME_crlf_copy(BIO *in, BIO *out, int flags)

{

	char eol;

	int len;

	char linebuf[MAX_SMLEN];

	if(flags & PKCS7_BINARY) {

		while((len = BIO_read(in, linebuf, MAX_SMLEN)) > 0)

						BIO_write(out, linebuf, len);

		return 1;

	}

	if(flags & PKCS7_TEXT)

		BIO_printf(out, "Content-Type: text/plain\r\n\r\n");

	while ((len = BIO_gets(in, linebuf, MAX_SMLEN)) > 0) {

		eol = strip_eol(linebuf, &len);

		if (len)

			BIO_write(out, linebuf, len);

		if(eol) BIO_write(out, "\r\n", 2);

	}

	return 1;

}

/* Strip off headers if they are text/plain */

EXPORT_C int SMIME_text(BIO *in, BIO *out)

{

#ifndef SYMBIAN	

	char iobuf[4096];

#else

  char iobuf[512];

#endif	

	int len;

	STACK_OF(MIME_HEADER) *headers;

	MIME_HEADER *hdr;

	if (!(headers = mime_parse_hdr(in))) {

		PKCS7err(PKCS7_F_SMIME_TEXT,PKCS7_R_MIME_PARSE_ERROR);

		return 0;

	}

	if(!(hdr = mime_hdr_find(headers, "content-type")) || !hdr->value) {

		PKCS7err(PKCS7_F_SMIME_TEXT,PKCS7_R_MIME_NO_CONTENT_TYPE);

		sk_MIME_HEADER_pop_free(headers, mime_hdr_free);

		return 0;

	}

	if (strcmp (hdr->value, "text/plain")) {

		PKCS7err(PKCS7_F_SMIME_TEXT,PKCS7_R_INVALID_MIME_TYPE);

		ERR_add_error_data(2, "type: ", hdr->value);

		sk_MIME_HEADER_pop_free(headers, mime_hdr_free);

		return 0;

	}

	sk_MIME_HEADER_pop_free(headers, mime_hdr_free);

	while ((len = BIO_read(in, iobuf, sizeof(iobuf))) > 0)

						BIO_write(out, iobuf, len);

	return 1;

}

/* Split a multipart/XXX message body into component parts: result is

 * canonical parts in a STACK of bios

 */

static int multi_split(BIO *bio, char *bound, STACK_OF(BIO) **ret)

{

	char linebuf[MAX_SMLEN];

	int len, blen;

	int eol = 0, next_eol = 0;

	BIO *bpart = NULL;

	STACK_OF(BIO) *parts;

	char state, part, first;

	blen = strlen(bound);

	part = 0;

	state = 0;

	first = 1;

	parts = sk_BIO_new_null();

	*ret = parts;

	while ((len = BIO_gets(bio, linebuf, MAX_SMLEN)) > 0) {

		state = mime_bound_check(linebuf, len, bound, blen);

		if(state == 1) {

			first = 1;

			part++;

		} else if(state == 2) {

			sk_BIO_push(parts, bpart);

			return 1;

		} else if(part) {

			/* Strip CR+LF from linebuf */

			next_eol = strip_eol(linebuf, &len);

			if(first) {

				first = 0;

				if(bpart) sk_BIO_push(parts, bpart);

				bpart = BIO_new(BIO_s_mem());

				BIO_set_mem_eof_return(bpart, 0);

			} else if (eol)

				BIO_write(bpart, "\r\n", 2);

			eol = next_eol;

			if (len)

				BIO_write(bpart, linebuf, len);

		}

	}

	return 0;

}

/* This is the big one: parse MIME header lines up to message body */

#define MIME_INVALID	0

#define MIME_START	1

#define MIME_TYPE	2

#define MIME_NAME	3

#define MIME_VALUE	4

#define MIME_QUOTE	5

#define MIME_COMMENT	6

static STACK_OF(MIME_HEADER) *mime_parse_hdr(BIO *bio)

{

	char *p, *q, c;

	char *ntmp;

	char linebuf[MAX_SMLEN];

	MIME_HEADER *mhdr = NULL;

	STACK_OF(MIME_HEADER) *headers;

	int len, state, save_state = 0;

	headers = sk_MIME_HEADER_new(mime_hdr_cmp);

	while ((len = BIO_gets(bio, linebuf, MAX_SMLEN)) > 0) {

	/* If whitespace at line start then continuation line */

	if(mhdr && isspace((unsigned char)linebuf[0])) state = MIME_NAME;

	else state = MIME_START;

	ntmp = NULL;

	/* Go through all characters */

	for(p = linebuf, q = linebuf; (c = *p) && (c!='\r') && (c!='\n'); p++) {

	/* State machine to handle MIME headers

	 * if this looks horrible that's because it *is*

         */

		switch(state) {

			case MIME_START:

			if(c == ':') {

				state = MIME_TYPE;

				*p = 0;

				ntmp = strip_ends(q);

				q = p + 1;

			}

			break;

			case MIME_TYPE:

			if(c == ';') {

				mime_debug("Found End Value\n");

				*p = 0;