sip_msg.c

VoIP use SIP protocol interface

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident	"@(#)sip_msg.c	1.58	06/08/16 SMI"

#include"sip_msg.h"
#include "sip_miscdefs.h"
#include "sip_parse_generic.h"

#define	SIP_RESPONSE	"%s %d %s%s"
#define	SIP_REQUEST	"%s %s%s"

/* list of sent-by values registered by the UA */
sent_by_list_t	*sip_sent_by = NULL;
int		sip_sent_by_count = 0;

static int sip_add_name_aspec(_sip_msg_t *, char *, char *, char *, boolean_t,
    char *, char *);

/* Allocate a new sip msg struct. */
sip_msg_t
sip_new_msg()
{
	_sip_msg_t *sip_msg;

	sip_msg = calloc(1, sizeof (_sip_msg_t));
	if (sip_msg != NULL) {
		sip_msg->sip_msg_ref_cnt = 1;
		(void) pthread_mutex_init(&sip_msg->sip_msg_mutex, NULL);
	}
	return ((sip_msg_t)sip_msg);
}


/* Copy header values into ptr */
int
sip_copy_values(char *ptr, _sip_header_t *header)
{
	sip_header_value_t	value;
	int			tlen = 0;
	int			len = 0;
	boolean_t		first = B_TRUE;
	char			*p = ptr;
	char			*e;

	if (sip_parse_goto_values(header) != 0)
		return (0);

	len = header->sip_hdr_current - header->sip_hdr_start;
	(void) strncpy(p, header->sip_hdr_start, len);
	tlen += len;
	p += len;
	value = header->sip_hdr_parsed->value;
	while (value != NULL) {
		if (value->value_state != SIP_VALUE_DELETED) {
			len = value->value_end - value->value_start;
			if (first) {
				(void) strncpy(p, value->value_start, len);
				first = B_FALSE;
			} else {
				e = value->value_start;
				while (*e != SIP_COMMA)
					e--;
				len += value->value_start - e;
				(void) strncpy(p, e, len);
			}
			tlen += len;
			p += len;
		}
		value = value->next;
	}
	return (tlen);
}

/* Returns number of bytes in the given int */
static int
sip_num_of_bytes(int num)
{
	int	num_of_bytes = 0;

	do {
		num_of_bytes += 1;
		num = num / 10;
	} while (num > 0);
	return (num_of_bytes);
}

/*
 * This is called just before sending the message to the transport. It
 * creates the sip_msg_buf from the SIP headers.
 */
int
sip_adjust_msgbuf(_sip_msg_t *msg)
{
	_sip_header_t	*header;
	int		ret;
#ifdef	_DEBUG
	int		tlen = 0;
	int		clen = 0;
#endif

	if (msg == NULL)
		return (EINVAL);

	(void) pthread_mutex_lock(&msg->sip_msg_mutex);
	if ((msg->sip_msg_buf != NULL) && (!msg->sip_msg_modified)) {
		/*
		 * We could just be forwarding the message we
		 * received.
		 */
		(void) pthread_mutex_unlock(&msg->sip_msg_mutex);
		return (0);
	}

	/*
	 * We are sending a new message or a message that we received
	 * but have modified it. We keep the old
	 * msgbuf till the message is freed as some
	 * headers still point to it.
	 */

	assert(msg->sip_msg_old_buf == NULL);
	msg->sip_msg_old_buf = msg->sip_msg_buf;
	/*
	 * We add the content-length header here, if it has not
	 * already been added.
	 */
	header = sip_search_for_header(msg, SIP_CONTENT_LENGTH, NULL);
	if (header != NULL) {
		/*
		 * Mark the previous header as deleted.
		 */
		header->sip_header_state = SIP_HEADER_DELETED;
		header->sip_hdr_sipmsg->sip_msg_len -= header->sip_hdr_end -
		    header->sip_hdr_start;
	}
	(void) pthread_mutex_unlock(&msg->sip_msg_mutex);
	ret = sip_add_content_length(msg, msg->sip_msg_content_len);
	if (ret != 0) {
		(void) pthread_mutex_lock(&msg->sip_msg_mutex);
		return (ret);
	}
	(void) pthread_mutex_lock(&msg->sip_msg_mutex);
	msg->sip_msg_modified = B_FALSE;

	msg->sip_msg_buf = sip_msg_to_msgbuf((sip_msg_t)msg, &ret);
	if (msg->sip_msg_buf == NULL) {
		(void) pthread_mutex_unlock(&msg->sip_msg_mutex);
		return (ret);
	}
	/*
	 * Once the message has been sent it can not be modified
	 * any furthur as we keep a pointer to it for retransmission
	 */
	msg->sip_msg_cannot_be_modified = B_TRUE;

	(void) pthread_mutex_unlock(&msg->sip_msg_mutex);
	return (0);
}

/* Free the message content */
void
sip_free_content(_sip_msg_t *sip_msg)
{
	sip_content_t *content;

	if (sip_msg == NULL)
		return;
	content = sip_msg->sip_msg_content;
	while (content != NULL) {
		sip_content_t *content_tmp;

		content_tmp = content;
		content = content->sip_content_next;
		if (content_tmp->sip_content_allocated)
			free(content_tmp->sip_content_start);
		free(content_tmp);
	}
	sip_msg->sip_msg_content = NULL;
}

/* Free all resources */
void
sip_destroy_msg(_sip_msg_t *_sip_msg)
{
	(void) sip_delete_start_line(_sip_msg);
	(void) pthread_mutex_lock(&_sip_msg->sip_msg_mutex);
	assert(_sip_msg->sip_msg_ref_cnt == 0);
	sip_delete_all_headers((sip_msg_t)_sip_msg);
	sip_free_content(_sip_msg);
	if (_sip_msg->sip_msg_buf != NULL)
		free(_sip_msg->sip_msg_buf);

	if (_sip_msg->sip_msg_old_buf != NULL)
		free(_sip_msg->sip_msg_old_buf);

	while (_sip_msg->sip_msg_req_res != NULL) {
		sip_message_type_t	*sip_msg_type_ptr;

		sip_msg_type_ptr = _sip_msg->sip_msg_req_res->sip_next;
		if (sip_msg_type_ptr->is_request) {
			sip_request_t	*reqline;

			reqline = &sip_msg_type_ptr->U.sip_request;
			if (reqline->sip_parse_uri != NULL) {
				sip_free_parsed_uri(reqline->sip_parse_uri);
				reqline->sip_parse_uri = NULL;
			}
		}
		free(_sip_msg->sip_msg_req_res);
		_sip_msg->sip_msg_req_res = sip_msg_type_ptr;
	}
	(void) pthread_mutex_unlock(&_sip_msg->sip_msg_mutex);
	free(_sip_msg);
}

/* Free a sip msg struct. */
void
sip_free_msg(sip_msg_t sip_msg)
{
	_sip_msg_t	*msg;

	if (sip_msg == NULL)
		return;
	msg = (_sip_msg_t *)sip_msg;
	SIP_MSG_REFCNT_DECR(msg);
}

/* Hold a sip msg struct. */
void
sip_hold_msg(sip_msg_t sip_msg)
{
	_sip_msg_t	*msg;

	if (sip_msg == NULL)
		return;
	msg = (_sip_msg_t *)sip_msg;
	SIP_MSG_REFCNT_INCR(msg);
}

/* Check if the message can be modified. */
boolean_t
sip_ok_to_modify_message(_sip_msg_t *_sip_msg)
{
	if (_sip_msg == NULL)
		return (B_FALSE);
#ifdef	__solaris__
	assert(mutex_held(&_sip_msg->sip_msg_mutex));
#endif
	if (_sip_msg->sip_msg_cannot_be_modified)
		return (B_FALSE);
	if (_sip_msg->sip_msg_buf != NULL)
		_sip_msg->sip_msg_modified = B_TRUE;
	return (B_TRUE);
}

/* Add a response line to sip_response */
int
sip_add_response_line(sip_msg_t sip_response, int response, char *response_code)
{
	_sip_header_t	*new_header;
	int		header_size;
	_sip_msg_t	*_sip_response;
	int		ret;

	if (sip_response == NULL || response < 0 || response_code == NULL)
		return (EINVAL);
	_sip_response = (_sip_msg_t *)sip_response;
	(void) pthread_mutex_lock(&_sip_response->sip_msg_mutex);
	if (!sip_ok_to_modify_message(_sip_response)) {
		(void) pthread_mutex_unlock(&_sip_response->sip_msg_mutex);
		return (ENOTSUP);
	}
	header_size = strlen(SIP_VERSION) + SIP_SPACE +
	    SIP_SIZE_OF_STATUS_CODE + SIP_SPACE + strlen(response_code) +
	    strlen(SIP_CRLF);

	new_header = sip_new_header(header_size);
	if (new_header == NULL) {
		(void) pthread_mutex_unlock(&_sip_response->sip_msg_mutex);
		return (ENOMEM);
	}
	new_header->sip_hdr_sipmsg = _sip_response;

	(void) snprintf(new_header->sip_hdr_start, header_size + 1,
	    SIP_RESPONSE, SIP_VERSION, response, response_code, SIP_CRLF);

	new_header->sip_hdr_next = _sip_response->sip_msg_start_line;
	_sip_response->sip_msg_start_line = new_header;
	_sip_response->sip_msg_len += header_size;
	ret = sip_parse_first_line(_sip_response->sip_msg_start_line,
	    &_sip_response->sip_msg_req_res);
	(void) pthread_mutex_unlock(&_sip_response->sip_msg_mutex);
	return (ret);
}

/*
 * create a response based on the sip_request.
 * Copies Call-ID, CSeq, From, To and Via headers from the request.
 */
sip_msg_t
sip_create_response(sip_msg_t sip_request, int response, char *response_code,
    char *totag, char *mycontact)
{
	_sip_msg_t	*new_msg;
	_sip_msg_t	*_sip_request;
	boolean_t	ttag_present;

	if (sip_request == NULL || response_code == NULL)
		return (NULL);

	ttag_present =  sip_get_to_tag(sip_request, NULL) != NULL;

	new_msg = (_sip_msg_t *)sip_new_msg();
	if (new_msg == NULL)
		return (NULL);
	_sip_request = (_sip_msg_t *)sip_request;

	(void) pthread_mutex_lock(&_sip_request->sip_msg_mutex);

	/*
	 * Add response line.
	 */
	if (sip_add_response_line(new_msg, response, response_code) != 0)
		goto error;

	/*
	 * Copy Via headers
	 */
	if (_sip_find_and_copy_all_header(_sip_request, new_msg, SIP_VIA) != 0)
		goto error;

	/*
	 * Copy From header.
	 */
	if (_sip_find_and_copy_header(_sip_request, new_msg, SIP_FROM,
	    NULL)) {
		goto error;
	}
	/*
	 * Copy To header. If To tag is present, copy it, if not then
	 * add one if the repsonse is not provisional.
	 */
	if (ttag_present || (totag == NULL && response == SIP_TRYING)) {
		if (_sip_find_and_copy_header(_sip_request, new_msg, SIP_TO,
		    NULL)) {
			goto error;
		}
	} else {
		char		*xtra_param;
		boolean_t	tag_alloc = B_FALSE;
		int		taglen;

		if (totag == NULL) {
			totag = sip_guid();
			if (totag == NULL)
				goto error;
			tag_alloc = B_TRUE;
		}
		taglen = strlen(SIP_TAG) + strlen(totag) + 1;
		xtra_param = (char *)malloc(taglen);
		if (xtra_param == NULL) {
			if (tag_alloc)
				free(totag);
			goto error;
		}
		(void) snprintf(xtra_param, taglen, "%s%s", SIP_TAG, totag);
		if (tag_alloc)
			free(totag);
		if (_sip_find_and_copy_header(_sip_request, new_msg,
		    SIP_TO, xtra_param)) {
			free(xtra_param);
			goto error;
		}
		free(xtra_param);
	}

	/*
	 * Copy Call-ID header.
	 */
	if (_sip_find_and_copy_header(_sip_request, new_msg, SIP_CALL_ID, NULL))
		goto error;
	/*
	 * Copy CSEQ header
	 */
	if (_sip_find_and_copy_header(_sip_request, new_msg, SIP_CSEQ, NULL))
		goto error;
	/*
	 * Copy RECORD-ROUTE header, if present.
	 */
	if (sip_search_for_header(_sip_request, SIP_RECORD_ROUTE, NULL) !=
	    NULL) {
		if (_sip_find_and_copy_all_header(_sip_request, new_msg,
		    SIP_RECORD_ROUTE) != 0) {
			goto error;
		}
	}
	if (mycontact != NULL) {
		if (sip_add_contact(new_msg, NULL, mycontact, B_FALSE,
		    NULL) != 0) {
			goto error;
		}
	}
	(void) pthread_mutex_unlock(&_sip_request->sip_msg_mutex);
	return ((sip_msg_t)new_msg);
error:
	sip_free_msg((sip_msg_t)new_msg);
	(void) pthread_mutex_unlock(&_sip_request->sip_msg_mutex);
	return (NULL);
}

/* Add quotes to the give str and return the quoted string */
static char *
sip_add_aquot_to_str(char *str, boolean_t *alloc)
{
	char 		*new_str;
	char 		*tmp = str;
	int		size;

	while (isspace(*tmp))
		tmp++;

	*alloc = B_FALSE;
	if (*tmp != SIP_LAQUOT) {
		size = strlen(str) + 2 * sizeof (char);
		new_str = calloc(1, size + 1);
		if (new_str == NULL)
			return (NULL);
		new_str[0] = SIP_LAQUOT;
		new_str[1] = '\0';
		(void) strncat(new_str, str, strlen(str));
		(void) strncat(new_str, ">", 1);
		new_str[size] = '\0';
		*alloc = B_TRUE;
		return (new_str);
	}

	return (str);
}

/* Add an empty header */
static int
sip_add_empty_hdr(sip_msg_t sip_msg, char *hdr_name)
{
	_sip_header_t	*new_header;
	int 		header_size;
	_sip_msg_t 	*_sip_msg;
	int		csize = sizeof (char);

	if (sip_msg == NULL || hdr_name == NULL)
		return (EINVAL);
	_sip_msg = (_sip_msg_t *)sip_msg;
	(void) pthread_mutex_lock(&_sip_msg->sip_msg_mutex);
	if (!sip_ok_to_modify_message(_sip_msg)) {
		(void) pthread_mutex_unlock(&_sip_msg->sip_msg_mutex);
		return (ENOTSUP);
	}

	header_size = strlen(hdr_name) + SIP_SPACE + csize;

	new_header = sip_new_header(header_size);
	if (new_header == NULL) {
		(void) pthread_mutex_unlock(&_sip_msg->sip_msg_mutex);
		return (ENOMEM);
	}

	(void) snprintf(new_header->sip_hdr_start, header_size + 1,
	    "%s %c",  hdr_name, SIP_HCOLON);

	_sip_add_header(_sip_msg, new_header, B_TRUE, B_FALSE, hdr_name);
	(void) pthread_mutex_unlock(&_sip_msg->sip_msg_mutex);

	return (0);
}

/* Generic function to add a header with two strings to message */
static int
sip_add_2strs_to_msg(sip_msg_t sip_msg, char *hdr_name, char *str1,
    boolean_t qstr1, char *str2, char *plist, char sep)