sip_dialog.c

VoIP use SIP protocol interface

	dialog->sip_dlg_rset.sip_str_ptr[dialog->sip_dlg_rset.sip_str_len] =
	    '\0';
	if (uri != NULL) {
		if (first) {
			count = snprintf(rp, rpl, "%c %s %c", SIP_LAQUOT,
			    uri, SIP_RAQUOT);
		} else {
			count = snprintf(rp, rpl, "%c%c %s %c", SIP_COMMA,
			    SIP_LAQUOT, uri, SIP_RAQUOT);
		}
		rp += count;
		rpl -= count;
		free(uri);
	}
	assert(rp <= rset + rset_len);
	(void) snprintf(rhdr->sip_hdr_start, rset_len + strlen(SIP_CRLF) + 1,
	    "%s%s", rset, SIP_CRLF);
	free(rset);
	dialog->sip_dlg_route_set = (sip_header_t)rhdr;
	sip_dialog_free_rset(rset_head);
	return (0);
}

/*
 * UAC Behavior
 * The route set MUST be set to the list of URIs in the Record-Route
 * header field from the response, taken in reverse order and preserving
 * all URI parameters.
 *
 * UAS behavior
 * The route set MUST be set to the list of URIs in the Record-Route
 * header field from the request, taken in order and preserving all URI
 * parameters.
 */
static int
sip_dialog_get_route_set(_sip_dialog_t *dialog, _sip_msg_t *sip_msg, int what)
{
	sip_header_t		rrhdr;
	sip_hdr_value_t		*value;
	int			error;
	sip_dlg_route_set_t	*rset_head = NULL;
	sip_dlg_route_set_t	*rset_tail = NULL;
	sip_dlg_route_set_t	*rset;
	int			rset_cnt = 0;
	int			rset_len = 0;

	(void) pthread_mutex_lock(&sip_msg->sip_msg_mutex);
	rrhdr = sip_search_for_header(sip_msg, SIP_RECORD_ROUTE, NULL);
	while (rrhdr != NULL) {
		(void) pthread_mutex_unlock(&sip_msg->sip_msg_mutex);
		value = (sip_hdr_value_t *)sip_get_header_value(rrhdr, &error);
		while (value != NULL && error == 0) {
			char	*crlf;

			if (value->sip_value_state == SIP_VALUE_BAD) {
				value = (sip_hdr_value_t *)sip_get_next_value(
				    (sip_header_value_t)value, &error);
				continue;
			}
			rset = sip_add_route_to_set(value);
			if (rset == NULL)
				goto r_error;
			/* Add one for COMMA */
			rset_cnt++;
			rset_len += (value->sip_value_end -
			    value->sip_value_start);
			/* Check for CRLF */
			crlf = value->sip_value_end - strlen(SIP_CRLF);
			while (crlf != NULL &&
			    strncmp(crlf, SIP_CRLF, strlen(SIP_CRLF)) == 0) {
				rset_len -= strlen(SIP_CRLF);
				crlf -= strlen(SIP_CRLF);
			}
			if (rset_head == NULL) {
				assert(rset_tail == NULL);
				rset_head = rset_tail = rset;
			} else if (what == SIP_UAS_DIALOG) {
				rset_tail->sip_dlg_route_next = rset;
				rset_tail = rset;
			} else if (what == SIP_UAC_DIALOG) {
				rset->sip_dlg_route_next = rset_head;
				rset_head = rset;
			} else {
				assert(0);
			}
			value = (sip_hdr_value_t *)sip_get_next_value(
			    (sip_header_value_t)value, &error);
		}
		(void) pthread_mutex_lock(&sip_msg->sip_msg_mutex);
		rrhdr = sip_search_for_header(sip_msg, SIP_RECORD_ROUTE, rrhdr);
	}
	(void) pthread_mutex_unlock(&sip_msg->sip_msg_mutex);
	if (rset_cnt == 0)
		return (0);
	if (sip_dialog_set_route_hdr(dialog, rset_head, rset_cnt,
	    rset_len) != 0) {
		goto r_error;
	}
	return (0);
r_error:
	sip_dialog_free_rset(rset_head);
	return (ENOMEM);
}

/*
 * UAS behavior:
 * The remote sequence number MUST be set to the value of the sequence
 * number in the CSeq header field of the request.  The local sequence
 * number MUST be empty.  The call identifier component of the dialog ID
 * MUST be set to the value of the Call-ID in the request.  The local
 * tag component of the dialog ID MUST be set to the tag in the To field
 * in the response to the request (which always includes a tag), and the
 * remote tag component of the dialog ID MUST be set to the tag from the
 * From field in the request.  A UAS MUST be prepared to receive a
 * request without a tag in the From field, in which case the tag is
 * considered to have a value of null.
 * The remote URI MUST be set to the URI in the From field, and the
 * local URI MUST be set to the URI in the To field.
 * The remote target MUST be set to the URI from the Contact header field
 * of the request.
 *
 * UAC behavior:
 * The local sequence number MUST be set to the value of the sequence
 * number in the CSeq header field of the request.  The remote sequence
 * number MUST be empty (it is established when the remote UA sends a
 * request within the dialog).  The call identifier component of the
 * dialog ID MUST be set to the value of the Call-ID in the request.
 * The local tag component of the dialog ID MUST be set to the tag in
 * the From field in the request, and the remote tag component of the
 * dialog ID MUST be set to the tag in the To field of the response.  A
 * UAC MUST be prepared to receive a response without a tag in the To
 * field, in which case the tag is considered to have a value of null.
 * The remote URI MUST be set to the URI in the To field, and the local
 * URI MUST be set to the URI in the From field.
 * The remote target MUST be set to the URI from the Contact header field
 * of the response.
 */


/*
 * This is the routine that seeds a dialog.
 */
sip_dialog_t
sip_seed_dialog(sip_conn_object_t obj, _sip_msg_t *sip_msg,
    void (*func)(sip_dialog_t, sip_msg_t, void *), boolean_t dlg_on_fork,
    int dlg_type)
{
	_sip_dialog_t		*dialog;
	int			cseq;
	sip_header_t		fhdr = NULL;
	sip_header_t		thdr = NULL;
	sip_header_t		chdr;
	sip_header_t		cihdr;
	sip_header_t		evhdr = NULL;
	const struct sip_value	*value;
	sip_dialog_timer_obj_t	*tim_obj = NULL;
	const sip_str_t		*callid;
	sip_method_t		method;
	int			timer1 = sip_timer_T1;
	int			error;

	if (!sip_msg_is_request((sip_msg_t)sip_msg, &error))
		return (NULL);
	method = sip_get_request_method((sip_msg_t)sip_msg, &error);
	/* Only INVITE and SUBSCRIBE supported */
	if (error != 0 || (method != INVITE && method != SUBSCRIBE))
		return (NULL);

	if (dlg_type == SIP_UAS_DIALOG) {
		thdr = sip_dlg_xchg_from_to((sip_msg_t)sip_msg,
		    SIP_DLG_XCHG_FROM);
		(void) pthread_mutex_lock(&sip_msg->sip_msg_mutex);
	} else {
		(void) pthread_mutex_lock(&sip_msg->sip_msg_mutex);
		fhdr = sip_search_for_header(sip_msg, SIP_FROM, NULL);
	}
	cihdr = sip_search_for_header(sip_msg, SIP_CALL_ID, NULL);
	chdr = sip_search_for_header(sip_msg, SIP_CONTACT, NULL);
	if (method == SUBSCRIBE)
		evhdr = sip_search_for_header(sip_msg, SIP_EVENT, NULL);
	(void) pthread_mutex_unlock(&sip_msg->sip_msg_mutex);
	if ((fhdr == NULL && thdr == NULL) || cihdr == NULL || chdr == NULL ||
	    (method == SUBSCRIBE && evhdr == NULL)) {
		return (NULL);
	}

	/* Sanity check since we just store the headers in the dialog */
	if (sip_get_from_tag((sip_msg_t)sip_msg, NULL) == NULL ||
	    sip_get_from_uri_str((sip_msg_t)sip_msg, NULL) == NULL ||
	    ((cseq = sip_get_callseq_num((sip_msg_t)sip_msg, NULL)) == -1) ||
	    (callid = sip_get_callid((sip_msg_t)sip_msg, NULL)) == NULL ||
	    sip_get_to_uri_str((sip_msg_t)sip_msg, NULL) == NULL ||
	    ((value = sip_get_header_value(chdr, NULL)) == NULL) ||
	    sip_get_contact_uri_str((sip_header_value_t)value, NULL) == NULL) {
		return (NULL);
	}

	tim_obj = malloc(sizeof (sip_dialog_timer_obj_t));
	if (tim_obj == NULL)
		return (NULL);
	dialog = calloc(1, sizeof (_sip_dialog_t));
	if (dialog == NULL)
		return (NULL);

	/*
	 * We will take the TO header with the tag when we complete this
	 * dialog
	 */
	if (dlg_type == SIP_UAS_DIALOG) {
		dialog->sip_dlg_remote_uri_tag = thdr;
	} else {
		if ((dialog->sip_dlg_local_uri_tag = sip_dup_header(fhdr)) ==
		    NULL) {
			goto dia_err;
		}
	}
	if ((dialog->sip_dlg_remote_target = sip_dup_header(chdr)) == NULL ||
	    (dialog->sip_dlg_call_id = sip_dup_header(cihdr)) == NULL) {
		goto dia_err;
	}
	if (method == SUBSCRIBE) {
		dialog->sip_dlg_event = sip_dup_header(evhdr);
		if (dialog->sip_dlg_event == NULL) {
			goto dia_err;
		}
	}
	dialog->sip_dlg_rset.sip_str_ptr = NULL;
	dialog->sip_dlg_rset.sip_str_len = 0;
	dialog->sip_dlg_req_uri.sip_str_ptr = NULL;
	dialog->sip_dlg_req_uri.sip_str_len = 0;
	/* Get the route set from the request, if present */
	if (sip_dialog_get_route_set(dialog, sip_msg, dlg_type) != 0) {
		goto dia_err;
	}
	if (dlg_type == SIP_UAC_DIALOG)
		dialog->sip_dlg_local_cseq = cseq;
	else
		dialog->sip_dlg_remote_cseq = cseq;
	dialog->sip_dlg_type = dlg_type;
	dialog->sip_dlg_on_fork = dlg_on_fork;
	dialog->sip_dlg_method = method;
	/* Set the partial dialog timer with the INVITE timeout val */
	if (sip_conn_timer1 != NULL)
		timer1 = sip_conn_timer1(obj);
	SIP_INIT_TIMER(dialog->sip_dlg_timer, 64 * timer1);
	tim_obj->dialog = dialog;
	tim_obj->func = func;
	SIP_SCHED_TIMER(dialog->sip_dlg_timer, (void *)tim_obj,
	    sip_dlg_self_destruct);
	if (!SIP_IS_TIMER_RUNNING(dialog->sip_dlg_timer))
		goto dia_err;
	(void) pthread_mutex_init(&dialog->sip_dlg_mutex, NULL);

	if (dlg_type == SIP_UAC_DIALOG) {
		const sip_str_t	*local_tag;

		local_tag = sip_get_from_tag((sip_msg_t)sip_msg, NULL);
		assert(local_tag != NULL);
		sip_md5_hash(local_tag->sip_str_ptr, local_tag->sip_str_len,
		    callid->sip_str_ptr, callid->sip_str_len,
		    NULL, 0, NULL, 0, NULL, 0, NULL, 0,
		    (uchar_t *)dialog->sip_dlg_id);

		SIP_DLG_REFCNT_INCR(dialog);

		/* Add it to the partial hash table */
		if (sip_hash_add(sip_dialog_phash, (void *)dialog,
		    SIP_DIGEST_TO_HASH(dialog->sip_dlg_id)) != 0) {
			goto dia_err;
		}
	}
	return ((sip_dialog_t)dialog);
dia_err:
	sip_release_dialog_res(dialog);
	if (tim_obj != NULL)
		free(tim_obj);
	return (NULL);
}

/*
 * When creating a dialog from a NOTIFY request, we need to get the FROM
 * header for the dialog from the TO header of the NOTIFY.
 */
_sip_header_t *
sip_dlg_xchg_from_to(sip_msg_t sip_msg, int what)
{
	int			len;
	_sip_header_t		*newhdr;
	int			cnt;
	const struct sip_header	*hdr;
	int			hdrsize;
	int			error;

	hdr = sip_get_header(sip_msg, what == SIP_DLG_XCHG_FROM ? SIP_FROM :
	    SIP_TO, NULL, &error);
	if (error != 0 || hdr == NULL)
		return (NULL);
	if (sip_parse_goto_values((_sip_header_t *)hdr) != 0)
		return (NULL);
	len = hdr->sip_hdr_end - hdr->sip_hdr_current;
	if (what == SIP_DLG_XCHG_FROM) {
		hdrsize = len + strlen(SIP_TO) + SIP_SPACE + sizeof (char) +
		    SIP_SPACE;
	} else {
		hdrsize = len + strlen(SIP_FROM) + SIP_SPACE + sizeof (char) +
		    SIP_SPACE;
	}
	newhdr = sip_new_header(hdrsize);
	if (newhdr == NULL)
		return (NULL);
	if (what == SIP_DLG_XCHG_FROM) {
		cnt = snprintf(newhdr->sip_hdr_current, hdrsize + 1,
		    "%s %c ", SIP_TO, SIP_HCOLON);
	} else {
		cnt = snprintf(newhdr->sip_hdr_current, hdrsize + 1,
		    "%s %c ", SIP_FROM, SIP_HCOLON);
	}
	newhdr->sip_hdr_current += cnt;
	(void) strncpy(newhdr->sip_hdr_current, hdr->sip_hdr_current, len);
	newhdr->sip_hdr_current += len;
	assert(newhdr->sip_hdr_current == newhdr->sip_hdr_end);
	assert(hdr->sip_header_functions != NULL);

	/* FROM and TO have common parsing functions */
	newhdr->sip_header_functions = hdr->sip_header_functions;
	newhdr->sip_hdr_current = newhdr->sip_hdr_start;

	return (newhdr);
}

/*
 * This is the response that completes the dialog that was created
 * in sip_seed_dialog().
 */
sip_dialog_t
sip_complete_dialog(_sip_msg_t *sip_msg, _sip_dialog_t *dialog,
    void (*func)(sip_dialog_t, sip_msg_t, void *))
{
	_sip_header_t		*thdr;
	_sip_header_t		*evhdr = NULL;
	_sip_header_t		*substate = NULL;
	int			resp_code;
	const sip_str_t		*ttag;
	const sip_str_t		*remtag;
	const sip_str_t		*callid;
	const struct sip_value 	*val;
	sip_method_t		method;
	int			error = 0;
	int			prev_state;

	if (sip_msg_is_request((sip_msg_t)sip_msg, &error) && error == 0)
		method = sip_get_request_method((sip_msg_t)sip_msg, &error);
	else
		method = sip_get_callseq_method((sip_msg_t)sip_msg, &error);
	if (error != 0 || dialog == NULL ||
	    (sip_msg_is_request((sip_msg_t)sip_msg, &error) &&
	    (dialog->sip_dlg_method == INVITE || method != NOTIFY))) {
		return (NULL);
	}
	if ((dialog->sip_dlg_type == SIP_UAC_DIALOG && method != NOTIFY &&
	    sip_get_callseq_num((sip_msg_t)sip_msg, NULL) !=
	    dialog->sip_dlg_local_cseq) ||
	    (dialog->sip_dlg_type == SIP_UAS_DIALOG && method != NOTIFY &&
	    sip_get_callseq_num((sip_msg_t)sip_msg, NULL) !=
	    dialog->sip_dlg_remote_cseq)) {
		return (NULL);
	}
	if (method == NOTIFY) {
		const sip_str_t	*sstate;

		thdr = sip_dlg_xchg_from_to((sip_msg_t)sip_msg,
		    SIP_DLG_XCHG_FROM);
		(void) pthread_mutex_lock(&sip_msg->sip_msg_mutex);
		evhdr = sip_search_for_header(sip_msg, SIP_EVENT, NULL);
		if (evhdr == NULL) {
			(void) pthread_mutex_unlock(&sip_msg->sip_msg_mutex);
			return (NULL);
		}
		substate = sip_search_for_header(sip_msg,
		    SIP_SUBSCRIPTION_STATE, NULL);
		if (substate == NULL) {
			(void) pthread_mutex_unlock(&sip_msg->sip_msg_mutex);
			return (NULL);
		}
		(void) pthread_mutex_unlock(&sip_msg->sip_msg_mutex);