/*
 * Copyright (C) 2022 - OpenSIPS Solutions
 *
 * This file is part of opensips, a free SIP server.
 *
 * opensips is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version
 *
 * opensips is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 *
 */

#include "../../sr_module.h"
#include "../../dprint.h"
#include "../../mem/mem.h"
#include "../../lib/hash.h"
#include "../../socket_info.h"
#include "../../timer.h"
#include "../../parser/sdp/sdp.h"
#include "../../parser/parse_from.h"
#include "../../msg_translator.h"
#include "../../evi/evi_modules.h"
#include "../../mi/mi.h"
#include "../uac_auth/uac_auth.h"
#include "../../lib/digest_auth/digest_auth.h"

#include "../proto_msrp/msrp_api.h"
#include "msrp_ua.h"

#define MSRP_DEFAULT_PORT 2855

#define append_string(_d,_s,_len) \
	do{\
		memcpy((_d),(_s),(_len));\
		(_d) += (_len);\
	}while(0)

static int mod_init(void);
static void destroy(void);

mi_response_t *msrpua_mi_end(const mi_params_t *params,
	struct mi_handler *async_hdl);
mi_response_t *msrpua_mi_list(const mi_params_t *params,
	struct mi_handler *async_hdl);
mi_response_t *msrpua_mi_send_msg(const mi_params_t *params,
	struct mi_handler *async_hdl);
mi_response_t *msrpua_mi_start_session(const mi_params_t *params,
	struct mi_handler *async_hdl);

void load_msrp_ua(struct msrp_ua_binds *binds);

/* proto_msrp binds */
struct msrp_binds msrp_api;
/* proto_msrp registration handler */
void *msrp_hdl;

b2b_api_t b2b_api;

str my_msrp_uri_str;
struct msrp_url my_msrp_uri;

const struct socket_info *msrp_sock;

str adv_contact;

int msrpua_sessions_hsize = 10;
gen_hash_t *msrpua_sessions;

int cleanup_interval = 60;
int max_duration = 12*3600;

str relay_uri_str;
struct msrp_url relay_uri;

uac_auth_api_t uac_auth_api;

static str msrpua_mod_name = str_init("msrp_ua");

gen_lock_t *sdp_id_lock;
int *next_sdp_id;

static event_id_t evi_sess_new_id = EVI_ERROR;
static event_id_t evi_sess_end_id = EVI_ERROR;

static event_id_t evi_msg_rcv_id = EVI_ERROR;
static event_id_t evi_report_id = EVI_ERROR;

static str evi_sess_new_name = str_init("E_MSRP_SESSION_NEW");
static str evi_sess_end_name = str_init("E_MSRP_SESSION_END");

static str evi_msg_rcv_name = str_init("E_MSRP_MSG_RECEIVED");
static str evi_report_name = str_init("E_MSRP_REPORT_RECEIVED");

static evi_params_p evi_sess_params;

static evi_params_p evi_msg_rcv_params;
static evi_params_p evi_report_params;

static evi_param_p evi_sess_from_p, evi_sess_to_p, evi_sess_ruri_p,
	evi_sess_sid_p, evi_sess_types_p;

static evi_param_p evi_msg_rcv_sid_p, evi_msg_rcv_ctype_p, evi_msg_rcv_body_p;

static evi_param_p evi_report_sid_p, evi_report_msgid_p, evi_report_status_p,
	evi_report_brange_p;

static str evi_sess_from_pname = str_init("from_uri");
static str evi_sess_to_pname = str_init("to_uri");
static str evi_sess_ruri_pname = str_init("ruri");
static str evi_sess_sid_pname = str_init("session_id");
static str evi_sess_types_pname = str_init("content_types");

static str evi_msg_rcv_sid_pname = str_init("session_id");
static str evi_msg_rcv_ctype_pname = str_init("content_type");
static str evi_msg_rcv_body_pname = str_init("body");

static str evi_report_sid_pname = str_init("session_id");
static str evi_report_msgid_pname = str_init("message_id");
static str evi_report_status_pname = str_init("status");
static str evi_report_brange_pname = str_init("byte_range");

static const param_export_t params[] = {
	{"hash_size", INT_PARAM, &msrpua_sessions_hsize},
	{"cleanup_interval", INT_PARAM, &cleanup_interval},
	{"max_duration", INT_PARAM, &max_duration},
	{"my_uri", STR_PARAM, &my_msrp_uri_str},
	{"advertised_contact", STR_PARAM, &adv_contact.s},
	{"relay_uri", STR_PARAM, &relay_uri_str.s},
};

static const mi_export_t mi_cmds[] = {
	{ "msrp_ua_send_message", 0, 0, 0, {
		{msrpua_mi_send_msg, {"session_id", 0}},
		{msrpua_mi_send_msg, {"session_id", "failure_report", 0}},
		{msrpua_mi_send_msg, {"session_id", "success_report", 0}},
		{msrpua_mi_send_msg, {"session_id", "failure_report", "success_report", 0}},
		{msrpua_mi_send_msg, {"session_id", "mime", "body", 0}},
		{msrpua_mi_send_msg, {"session_id", "mime", "body", "failure_report", 0}},
		{msrpua_mi_send_msg, {"session_id", "mime", "body", "success_report", 0}},
		{msrpua_mi_send_msg, {"session_id", "mime", "body",
			"failure_report", "success_report", 0}},
		{EMPTY_MI_RECIPE}}
	},
	{ "msrp_ua_end_session", 0, 0, 0, {
		{msrpua_mi_end, {"session_id", 0}},
		{EMPTY_MI_RECIPE}}
	},
	{ "msrp_ua_list_sessions", 0, 0, 0, {
		{msrpua_mi_list, {0}},
		{EMPTY_MI_RECIPE}}
	},
	{ "msrp_ua_start_session", 0, 0, 0, {
		{msrpua_mi_start_session, {"content_types", "from_uri", "to_uri", "ruri", 0}},
		{EMPTY_MI_RECIPE}}
	},
	{EMPTY_MI_EXPORT}
};

static int msrpua_answer(struct sip_msg *msg, str *content_types);

static const cmd_export_t cmds[]=
{
	{"msrp_ua_answer", (cmd_function)msrpua_answer, {
		{CMD_PARAM_STR, 0, 0},
		{0,0,0}},
		REQUEST_ROUTE},
	{"load_msrp_ua", (cmd_function)load_msrp_ua, {{0,0,0}}, 0},
	{0,0,{{0,0,0}},0}
};

static module_dependency_t *get_deps_relay_uri(const param_export_t *param)
{
	if (*(int *)param->param_pointer == 0)
		return NULL;

	return alloc_module_dep(MOD_TYPE_DEFAULT, "uac_auth", DEP_ABORT);
}

static const dep_export_t deps = {
	{ /* OpenSIPS module dependencies */
		{ MOD_TYPE_DEFAULT, "proto_msrp"  , DEP_ABORT  },
		{ MOD_TYPE_DEFAULT, "b2b_entities", DEP_ABORT },
		{ MOD_TYPE_NULL, NULL, 0 },
	},
	{ /* modparam dependencies */
		{ "relay_uri", get_deps_relay_uri },
		{ NULL, NULL },
	},
};

struct module_exports exports = {
	"msrp_ua",       /* module name*/
	MOD_TYPE_DEFAULT,/* class of this module */
	MODULE_VERSION,
	DEFAULT_DLFLAGS, /* dlopen flags */
	0,               /* load function */
	&deps,      /* OpenSIPS module dependencies */
	cmds,       /* exported functions */
	0,          /* exported async functions */
	params,     /* module parameters */
	0,          /* exported statistics */
	mi_cmds,    /* exported MI functions */
	0,          /* exported pseudo-variables */
	0,          /* exported transformations */
	0,          /* extra processes */
	0,          /* module pre-initialization function */
	mod_init,   /* module initialization function */
	0,          /* response function */
	destroy,    /* destroy function */
	0,          /* per-child init function */
	0           /* reload confirm function */
};

static int handle_msrp_request(struct msrp_msg *req, void *hdl_param);
static int handle_msrp_reply(struct msrp_msg *rpl, struct msrp_cell *tran,
	void *trans_param, void *hdl_param);
static void clean_msrpua_sessions(unsigned int ticks,void *param);

static int msrpua_evi_init(void)
{
	evi_sess_new_id = evi_publish_event(evi_sess_new_name);
	if (evi_sess_new_id == EVI_ERROR) {
		LM_ERR("cannot register event\n");
		return -1;
	}
	evi_sess_end_id = evi_publish_event(evi_sess_end_name);
	if (evi_sess_end_id == EVI_ERROR) {
		LM_ERR("cannot register event\n");
		return -1;
	}
	evi_msg_rcv_id = evi_publish_event(evi_msg_rcv_name);
	if (evi_msg_rcv_id == EVI_ERROR) {
		LM_ERR("cannot register event\n");
		return -1;
	}
	evi_report_id = evi_publish_event(evi_report_name);
	if (evi_report_id == EVI_ERROR) {
		LM_ERR("cannot register event\n");
		return -1;
	}

	evi_sess_params = pkg_malloc(sizeof(evi_params_t));
	if (evi_sess_params == NULL) {
		LM_ERR("no more pkg mem\n");
		return -1;
	}
	memset(evi_sess_params, 0, sizeof(evi_params_t));

	evi_msg_rcv_params = pkg_malloc(sizeof(evi_params_t));
	if (evi_msg_rcv_params == NULL) {
		LM_ERR("no more pkg mem\n");
		return -1;
	}
	memset(evi_msg_rcv_params, 0, sizeof(evi_params_t));

	evi_report_params = pkg_malloc(sizeof(evi_params_t));
	if (evi_report_params == NULL) {
		LM_ERR("no more pkg mem\n");
		return -1;
	}
	memset(evi_report_params, 0, sizeof(evi_params_t));

	evi_sess_from_p = evi_param_create(evi_sess_params, &evi_sess_from_pname);
	if (evi_sess_from_p == NULL)
		goto error;
	evi_sess_to_p = evi_param_create(evi_sess_params, &evi_sess_to_pname);
	if (evi_sess_to_p == NULL)
		goto error;
	evi_sess_ruri_p = evi_param_create(evi_sess_params, &evi_sess_ruri_pname);
	if (evi_sess_ruri_p == NULL)
		goto error;
	evi_sess_sid_p = evi_param_create(evi_sess_params, &evi_sess_sid_pname);
	if (evi_sess_sid_p == NULL)
		goto error;
	evi_sess_types_p = evi_param_create(evi_sess_params, &evi_sess_types_pname);
	if (evi_sess_types_p == NULL)
		goto error;

	evi_msg_rcv_sid_p = evi_param_create(evi_msg_rcv_params,
		&evi_msg_rcv_sid_pname);
	if (evi_msg_rcv_sid_p == NULL)
		goto error;
	evi_msg_rcv_ctype_p = evi_param_create(evi_msg_rcv_params,
		&evi_msg_rcv_ctype_pname);
	if (evi_msg_rcv_ctype_p == NULL)
		goto error;
	evi_msg_rcv_body_p = evi_param_create(evi_msg_rcv_params,
		&evi_msg_rcv_body_pname);
	if (evi_msg_rcv_body_p == NULL)
		goto error;

	evi_report_sid_p = evi_param_create(evi_report_params,
		&evi_report_sid_pname);
	if (evi_report_sid_p == NULL)
		goto error;
	evi_report_msgid_p = evi_param_create(evi_report_params,
		&evi_report_msgid_pname);
	if (evi_report_msgid_p == NULL)
		goto error;
	evi_report_status_p = evi_param_create(evi_report_params,
		&evi_report_status_pname);
	if (evi_report_status_p == NULL)
		goto error;
	evi_report_brange_p = evi_param_create(evi_report_params,
		&evi_report_brange_pname);
	if (evi_report_brange_p == NULL)
		goto error;

	return 0;

error:
	LM_ERR("cannot create event parameter\n");
	return -1;
}

static int mod_init(void)
{
	LM_INFO("initializing...\n");
	char *p, *end;

	if (!my_msrp_uri_str.s) {
		LM_ERR("'my_uri' parameter not set\n");
		return -1;
	}

	if (adv_contact.s)
		adv_contact.len = strlen(adv_contact.s);
	
	my_msrp_uri_str.len = strlen(my_msrp_uri_str.s);

	end = my_msrp_uri_str.s + my_msrp_uri_str.len;
	p = parse_msrp_url(my_msrp_uri_str.s, end, &my_msrp_uri);
	if (!p) {
		LM_ERR("Failed to parse MSRP URI in 'my_uri' parameter\n");
		return -1;
	}

	if (my_msrp_uri.port_no == 0) {
		LM_INFO("Explicit port number not provided in 'my_uri',"
			"using default %d\n", MSRP_DEFAULT_PORT);
		my_msrp_uri.port_no = MSRP_DEFAULT_PORT;
	}

	msrp_sock = grep_sock_info(&my_msrp_uri.host, my_msrp_uri.port_no,
		my_msrp_uri.secured ? PROTO_MSRPS:PROTO_MSRP);
	if (!msrp_sock) {
		LM_ERR("non-local socket <%.*s>\n",
			my_msrp_uri.host.len, my_msrp_uri.host.s);
		return 1;
	}

	if (relay_uri_str.s) {
		relay_uri_str.len = strlen(relay_uri_str.s);

		end = relay_uri_str.s + relay_uri_str.len;
		p = parse_msrp_url(relay_uri_str.s, end, &relay_uri);
		if (!p) {
			LM_ERR("Failed to parse MSRP URI in 'relay_uri' parameter\n");
			return -1;
		}

		if(load_uac_auth_api(&uac_auth_api)<0){
			LM_ERR("can't load UAC_AUTH API, needed for uac_auth()\n");
			return -1;
		}
	}

	/* load MSRP API */
	if(load_msrp_api(&msrp_api)< 0){
		LM_ERR("can't load MSRP functions\n");
		return -1;
	}

	msrp_hdl = msrp_api.register_msrp_handler(&my_msrp_uri.host,
		my_msrp_uri.port_no, my_msrp_uri.secured, handle_msrp_request,
		handle_msrp_reply, NULL);
	if (!msrp_hdl) {
		LM_ERR("Failed to register MSRP handler\n");
		return -1;
	}

	if (load_b2b_api(&b2b_api) < 0) {
		LM_ERR("Failed to load b2b api\n");
		return -1;
	}

	if (msrpua_sessions_hsize < 1 || msrpua_sessions_hsize > 20) {
		LM_ERR("hash size should be between 1 and 20\n");
		return -1;
	}
	msrpua_sessions_hsize = 1 << msrpua_sessions_hsize;

	msrpua_sessions = hash_init(msrpua_sessions_hsize);
	if (!msrpua_sessions) {
		LM_ERR("Failed to init MSRP sessions table\n");
		return -1;
	}

	register_timer("msrpua-expire", clean_msrpua_sessions, NULL,
		cleanup_interval, TIMER_FLAG_DELAY_ON_DELAY);

	sdp_id_lock = lock_alloc();
	if (!sdp_id_lock) {
		LM_ERR("no more shm memory\n");
		return -1;
	}
	if (!lock_init(sdp_id_lock)) {
		LM_ERR("failed to init lock\n");
		return -1;
	}

	next_sdp_id = shm_malloc(sizeof *next_sdp_id);
	if (!next_sdp_id) {
		LM_ERR("no more shm memory\n");
		return -1;
	}
	*next_sdp_id = time(NULL);

	if (msrpua_evi_init() < 0) {
		LM_ERR("Failed to init events\n");
		return -1;
	}

	return 0;
}

static void free_msrpua_session(void *val)
{
	struct msrpua_session *sess = (struct msrpua_session *)val;

	if (sess->use_path.s)
		shm_free(sess->use_path.s);

	if (sess->peer_path.s)
		shm_free(sess->peer_path.s);
	free_msrp_path_shm(sess->peer_path_parsed);

	if (sess->peer_accept_types.s)
		shm_free(sess->peer_accept_types.s);

	if (sess->dlginfo)
		shm_free(sess->dlginfo);

	if (sess->ruri.s)
		shm_free(sess->ruri.s);

	shm_free(sess);
}

static void msrpua_delete_session(struct msrpua_session *sess)
{
	LM_DBG("Deleting session [%.*s]\n", sess->session_id.len, sess->session_id.s);

	if (sess->b2b_key.s)
		b2b_api.entity_delete(sess->b2b_type, &sess->b2b_key, sess->dlginfo, 1, 1);

	hash_remove_key(msrpua_sessions, sess->session_id);
	free_msrpua_session(sess);
}

void msrpua_evi_destroy(void)
{
	evi_free_params(evi_sess_params);
}

static void destroy(void)
{
	hash_destroy(msrpua_sessions, free_msrpua_session);

	lock_destroy(sdp_id_lock);
	lock_dealloc(sdp_id_lock);

	msrpua_evi_destroy();
}

static inline int msrpua_b2b_reply(int et, str *b2b_key, int method,
	int code, str *reason, str *body)
{
	b2b_rpl_data_t rpl_data;
	static str ct_type_sdp_str = str_init("Content-Type: application/sdp\r\n");

	memset(&rpl_data, 0, sizeof(b2b_rpl_data_t));
	rpl_data.et = et;
	rpl_data.b2b_key = b2b_key;
	rpl_data.method = method;
	rpl_data.code = code;
	rpl_data.text = reason;
	rpl_data.body = body;
	if (body)
		rpl_data.extra_headers = &ct_type_sdp_str;

	return b2b_api.send_reply(&rpl_data);
}

static inline int msrpua_b2b_request(int et, str *b2b_key, str *method)
{
	b2b_req_data_t req_data;

	memset(&req_data, 0, sizeof(b2b_req_data_t));
	req_data.et = et;
	req_data.b2b_key = b2b_key;
	req_data.method = method;

	return b2b_api.send_request(&req_data);
}

#define MESSAGE_STR "message"
#define TCP_MSRP_STR "TCP/MSRP"
#define TLS_MSRP_STR "TCP/TLS/MSRP"

static sdp_stream_cell_t *get_sdp_msrp_stream(sdp_info_t *sdp)
{
	sdp_session_cell_t* sdp_session;
	sdp_stream_cell_t* sdp_stream;
	int sdp_session_num = 0, sdp_stream_num;

	for (;;) {
		sdp_session = get_sdp_session(sdp, sdp_session_num);
		if (!sdp_session)
			break;

		sdp_stream_num = 0;
		for (;;) {
			sdp_stream = get_sdp_stream(sdp, sdp_session_num,
				sdp_stream_num);
			if (!sdp_stream)
				break;

			if (str_match(&sdp_stream->media, const_str(MESSAGE_STR)) &&
				(str_match(&sdp_stream->transport, const_str(TCP_MSRP_STR)) ||
				str_match(&sdp_stream->transport, const_str(TLS_MSRP_STR))))
				return sdp_stream;

			sdp_stream_num++;
		}

		sdp_session_num++;
	}

	return NULL;
}

static int get_sdp_peer_info(struct sip_msg *msg, str *peer_accept_types,
	str *peer_path)
{
	sdp_info_t *sdp;
	sdp_stream_cell_t *msrp_stream;

	if (!(sdp = parse_sdp(msg))) {
		LM_DBG("failed to parse SDP\n");
		return -1;
	}

	if (!(msrp_stream = get_sdp_msrp_stream(sdp))) {
		LM_ERR("No MSRP media stream in SDP\n");
		return -1;
	}

	*peer_accept_types = msrp_stream->accept_types;
	*peer_path = msrp_stream->path;

	return 0;
	}

static inline int match_mimes(str *a_type, str *a_subtype,
	str *b_type, str *b_subtype)
{
	if (a_type->len != b_type->len || memcmp(a_type->s, b_type->s, b_type->len))
		return 0;

	if (a_subtype->s[0] == '*' || b_subtype->s[0] == '*')
		return 1;
	else if (a_subtype->len != b_subtype->len ||
		memcmp(a_subtype->s, b_subtype->s, b_subtype->len))
		return 0;
	else
		return 1;
}

static int match_mime_with_list(str *mime, str *list)
{
	enum state {
		MLIST_TYPE_ST,
		MLIST_SUBTYPE_ST
	};
	enum state st;
	str src_type = STR_NULL, src_subtype = STR_NULL;
	str type = STR_NULL, subtype = STR_NULL;
	char *p;

	if (mime->len == 0)
		goto err_mime;

	if (mime->s[0] == '*') {
		if (mime->len != 1)
			goto err_mime;
		return 1;
	}

	src_type.s = mime->s;
	src_subtype.s = q_memchr(mime->s, '/', mime->len);
	if (!src_subtype.s)
		goto err_mime;
	src_type.len = src_subtype.s - src_type.s;
	src_subtype.s++;

	if (mime->len - src_type.len - 1 == 0)
		goto err_mime;

	/* ignore type params */
	p = q_memchr(src_subtype.s, ';', mime->len - src_type.len - 1);
	if (p)
		src_subtype.len = p - src_subtype.s;
	else
		src_subtype.len = mime->len - src_type.len - 1;

 	if (list->s[0] == '*') {
 		if (list->len != 1)
 			goto err_list;
 		return 1;
 	}

	p = list->s;
	st = MLIST_TYPE_ST;
	type.s = p;

	while (p < list->s + list->len) {
		switch (st) {
		case MLIST_TYPE_ST:
			switch (*p) {
			case '/':
				type.len = p - type.s;
				subtype.s = p+1;
				st = MLIST_SUBTYPE_ST;
				break;
			case ' ':
			case '*':
				goto err_list;
			}

			break;
		case MLIST_SUBTYPE_ST:
			switch (*p) {
			case '/':
				goto err_list;
			case ' ':
				subtype.len = p - subtype.s;
				if (match_mimes(&src_type, &src_subtype, &type, &subtype))
					return 1;

				type.s = p+1;
				st = MLIST_TYPE_ST;				
			}
		}

		p++;
	}

	if (st != MLIST_SUBTYPE_ST)
		goto err_list;

	subtype.len = p - subtype.s;
	if (match_mimes(&src_type, &src_subtype, &type, &subtype))
		return 1;	

	return 0;

err_mime:
	LM_ERR("Bad MIME format [%.*s]\n", mime->len, mime->s);
	return 0;
err_list:
	LM_ERR("Bad format for accept-types [%.*s]\n", list->len, list->s);
	return 0;
}

static int check_offer_types(str *accept_types, str *peer_accept_types)
{
	str mime = STR_NULL;
	char *p = accept_types->s;

	mime.s = accept_types->s;
	while (p < accept_types->s + accept_types->len) {
		if (*p == ' ') {
			mime.len = p - mime.s;
			if (match_mime_with_list(&mime, peer_accept_types))
				return 1;

			mime.s = p+1;
		} else {
			p++;
		}
	}

	mime.len = p - mime.s;
	if (match_mime_with_list(&mime, peer_accept_types))
		return 1;

	return 0;
}

#define SDP_V_LINE_STR "v=0\r\n"
#define SDP_V_LINE_STR_LEN (sizeof(SDP_V_LINE_STR) - 1)
#define SDP_S_LINE_STR "s= -\r\n"
#define SDP_S_LINE_STR_LEN (sizeof(SDP_S_LINE_STR) - 1)
#define SDP_T_LINE_STR "t=0 0\r\n"
#define SDP_T_LINE_STR_LEN (sizeof(SDP_T_LINE_STR) - 1)

#define SDP_O_STR "o=- "
#define SDP_O_STR_LEN (sizeof(SDP_O_STR) - 1)

#define SDP_IP4_STR "IN IP4 "
#define SDP_IP4_STR_LEN (sizeof(SDP_IP4_STR) - 1)
#define SDP_IP6_STR "IN IP6 "
#define SDP_IP6_STR_LEN (sizeof(SDP_IP6_STR) - 1)

#define SDP_C_STR "c="
#define SDP_C_STR_LEN (sizeof(SDP_C_STR) - 1)

#define SDP_M_STR "m=message "
#define SDP_M_STR_LEN (sizeof(SDP_M_STR) - 1)
#define SDP_M_TCP_STR " TCP/MSRP *\r\n"
#define SDP_M_TCP_STR_LEN (sizeof(SDP_M_TCP_STR) - 1)
#define SDP_M_TLS_STR " TCP/TLS/MSRP *\r\n"
#define SDP_M_TLS_STR_LEN (sizeof(SDP_M_TLS_STR) - 1)

#define SDP_A_TYPES_STR "a=accept-types:"
#define SDP_A_TYPES_STR_LEN (sizeof(SDP_A_TYPES_STR) - 1)
#define SDP_A_PATH_STR "a=path:"
#define SDP_A_PATH_STR_LEN (sizeof(SDP_A_PATH_STR) - 1)

static str *msrpua_build_sdp(struct msrpua_session *sess, str *accept_types)
{
	static str buf;
	char *p;
	str id;
	str vers;

	id.s = int2str(sess->sdp_sess_id, &id.len);
	vers.s = int2str(sess->sdp_sess_vers, &vers.len);

	buf.len = SDP_V_LINE_STR_LEN + SDP_S_LINE_STR_LEN + SDP_T_LINE_STR_LEN;
	buf.len += SDP_O_STR_LEN + id.len + 1 + vers.len + 1 +
		(msrp_sock->address.af==AF_INET ? SDP_IP4_STR_LEN:SDP_IP6_STR_LEN) +
		my_msrp_uri.host.len + CRLF_LEN;
	buf.len += SDP_C_STR_LEN +
		(msrp_sock->address.af==AF_INET ? SDP_IP4_STR_LEN:SDP_IP6_STR_LEN) + 
		my_msrp_uri.host.len + CRLF_LEN;
	buf.len += SDP_M_STR_LEN + my_msrp_uri.port.len +
		(my_msrp_uri.secured ? SDP_M_TLS_STR_LEN:SDP_M_TCP_STR_LEN);
	buf.len += SDP_A_TYPES_STR_LEN + accept_types->len + CRLF_LEN +
		SDP_A_PATH_STR_LEN + my_msrp_uri.whole.len + 1 + sess->session_id.len +
		CRLF_LEN;
	if (relay_uri_str.s)
		buf.len += sess->use_path.len + 1;

	buf.s = pkg_malloc(buf.len);
	if (!buf.s) {
		LM_ERR("no more pkg memory\n");
		return NULL;
	}
	p = buf.s;

	append_string(p, SDP_V_LINE_STR, SDP_V_LINE_STR_LEN);

	append_string(p, SDP_O_STR, SDP_O_STR_LEN);
	append_string(p, id.s, id.len);
	*(p++) = ' ';
	append_string(p, vers.s, vers.len);
	*(p++) = ' ';
	if (msrp_sock->address.af==AF_INET)
		append_string(p, SDP_IP4_STR, SDP_IP4_STR_LEN);
	else
		append_string(p, SDP_IP6_STR, SDP_IP6_STR_LEN);
	append_string(p, my_msrp_uri.host.s, my_msrp_uri.host.len);
	append_string(p, CRLF, CRLF_LEN);

	append_string(p, SDP_S_LINE_STR, SDP_S_LINE_STR_LEN);

	append_string(p, SDP_C_STR, SDP_C_STR_LEN);
	if (msrp_sock->address.af==AF_INET)
		append_string(p, SDP_IP4_STR, SDP_IP4_STR_LEN);
	else
		append_string(p, SDP_IP6_STR, SDP_IP6_STR_LEN);
	append_string(p, my_msrp_uri.host.s, my_msrp_uri.host.len);
	append_string(p, CRLF, CRLF_LEN);

	append_string(p, SDP_T_LINE_STR, SDP_T_LINE_STR_LEN);

	append_string(p, SDP_M_STR, SDP_M_STR_LEN);
	append_string(p, my_msrp_uri.port.s, my_msrp_uri.port.len);
	if (my_msrp_uri.secured)
		append_string(p, SDP_M_TLS_STR, SDP_M_TLS_STR_LEN);
	else
		append_string(p, SDP_M_TCP_STR, SDP_M_TCP_STR_LEN);

	append_string(p, SDP_A_TYPES_STR, SDP_A_TYPES_STR_LEN);
	append_string(p, accept_types->s, accept_types->len);
	append_string(p, CRLF, CRLF_LEN);

	append_string(p, SDP_A_PATH_STR, SDP_A_PATH_STR_LEN);
	if (relay_uri_str.s) {
		append_string(p, sess->use_path.s, sess->use_path.len);
		*(p++) = ' ';
	}
	append_string(p, my_msrp_uri.whole.s,
		my_msrp_uri.whole.len - my_msrp_uri.params.len - 1);
	*(p++) = '/';
	append_string(p, sess->session_id.s, sess->session_id.len);
	*(p++) = ';';
	append_string(p, my_msrp_uri.params.s, my_msrp_uri.params.len);
	append_string(p, CRLF, CRLF_LEN);

	if (p - buf.s != buf.len) {
		LM_BUG("computed: %d, but wrote %d\n",buf.len,(int)(p-buf.s));
		return NULL;
	}

	return &buf;
}

static int update_peer_path(struct msrpua_session *sess)
{
	str tmp;

	if (pkg_str_dup(&tmp, &sess->peer_path) < 0) {
		LM_ERR("no more pkg memory\n");
		return -1;
	}

	if (shm_str_extend(&sess->peer_path,
		sess->peer_path.len + sess->use_path.len + 1) != 0) {
		LM_ERR("no more shm memory\n");
		goto error;
	}

	memcpy(sess->peer_path.s, sess->use_path.s, sess->use_path.len);
	sess->peer_path.s[sess->use_path.len] = ' ';
	memcpy(sess->peer_path.s + sess->use_path.len + 1, tmp.s, tmp.len);

	pkg_free(tmp.s);

	sess->peer_path_parsed = parse_msrp_path_shm(&sess->peer_path);
	if (!sess->peer_path_parsed ) {
		LM_ERR("Failed to parse MSRP peer path\n");
		return -1;
	}

	return 0;
error:
	pkg_free(tmp.s);
	return -1;
}

static int msrpua_update_send_200ok(struct msrpua_session *sess, int etype)
{
	int code;
	str reason;
	str *sdp;

	sess->sdp_sess_vers++;

	sdp = msrpua_build_sdp(sess, &sess->accept_types);
	if (!sdp) {
		LM_ERR("Failed to build SDP answer\n");
		code = 500;
		reason = str_init("Internal Server Error");
		goto err_reply;
	}

	if (msrpua_b2b_reply(etype, &sess->b2b_key, METHOD_INVITE,
		200, &str_init("OK"), sdp) < 0) {
		LM_ERR("Failed to send 200 OK\n");
		pkg_free(sdp->s);
		goto err;
	}

	sess->dlg_state = MSRPUA_DLG_CONF;

	pkg_free(sdp->s);

	return 0;

err_reply:
	if (msrpua_b2b_reply(etype, &sess->b2b_key, METHOD_INVITE,
		code, &reason, NULL) < 0) {
		LM_ERR("Failed to send error reply\n");
	}
err:
	if (msrpua_b2b_request(etype, &sess->b2b_key, &str_init("BYE")) < 0)
		LM_ERR("Failed to send BYE on error\n");
	msrpua_delete_session(sess);

	return -1;
}

#define REASON_488_STR "Not Acceptable Here"

static int msrpua_update_session(struct msrpua_session *sess,
	struct sip_msg *msg, int etype, int is_reinvite)
{
	str peer_accept_types;
	str peer_path;
	int code;
	str reason;
	int del_sess = 0;

	if (get_sdp_peer_info(msg, &peer_accept_types, &peer_path) < 0) {
		LM_ERR("Failed to get peer info from SDP\n");
		code = 488;
		reason = str_init(REASON_488_STR);
		goto err_reply;
	}

	/* match at least one content type from our accept_types 
	 * with the peer's accept_types */
	if (!check_offer_types(&sess->accept_types, &peer_accept_types)) {
		LM_ERR("Cannot understand any content type received in the offer\n");
		code = 488;
		reason = str_init(REASON_488_STR);
		goto err_reply;
	}

	if (relay_uri_str.s) {
		if (update_peer_path(sess) < 0) {
			LM_ERR("Failed to update peer path with the relay URI\n");
			code = 500;
			reason = str_init("Internal Server Error");
			del_sess = 1;
			goto err_reply;
		}
	} else {
		if (shm_str_sync(&sess->peer_path, &peer_path) < 0) {
			LM_ERR("No more shm memory\n");
			code = 500;
			reason = str_init("Internal Server Error");
			del_sess = 1;
			goto err_reply;
		}
	}

	sess->peer_path_parsed = parse_msrp_path_shm(&sess->peer_path);
	if (!sess->peer_path_parsed ) {
		LM_ERR("Failed to parse MSRP peer path\n");
		code = 500;
		reason = str_init("Internal Server Error");
		del_sess = 1;
		goto err_reply;
	}

	memset(&sess->to_su, 0, sizeof sess->to_su);

	if (shm_str_sync(&sess->peer_accept_types, &peer_accept_types) < 0) {
		LM_ERR("No more shm memory\n");
		code = 500;
		reason = str_init("Internal Server Error");
		del_sess = 1;
		goto err_reply;
	}

	if (is_reinvite)
		return msrpua_update_send_200ok(sess, etype);
	else
		return 0;

err_reply:
	if (is_reinvite && msrpua_b2b_reply(etype, &sess->b2b_key, METHOD_INVITE,
		code, &reason, NULL) < 0) {
		LM_ERR("Failed to send error reply\n");
		del_sess = 1;
	}
	if (del_sess) {
		if (msrpua_b2b_request(etype, &sess->b2b_key, &str_init("BYE")) < 0)
			LM_ERR("Failed to send BYE on error\n");
		msrpua_delete_session(sess);
	}
	return -1;
}

static int raise_sess_new_event(struct sip_msg *msg, str *sess_id, str *ruri,
	str *accept_types)
{
	if (parse_from_header(msg) < 0) {
		LM_ERR("cannot parse From header\n");
		return -1;
	}
	if (parse_to_header(msg) < 0) {
		LM_ERR("cannot parse To header\n");
		return -1;
	}

	if (evi_param_set_str(evi_sess_from_p, &get_from(msg)->uri) < 0) {
		LM_ERR("cannot set event parameter\n");
		return -1;
	}
	if (evi_param_set_str(evi_sess_to_p, &get_to(msg)->uri) < 0) {
		LM_ERR("cannot set event parameter\n");
		return -1;
	}
	if (evi_param_set_str(evi_sess_ruri_p, ruri) < 0) {
		LM_ERR("cannot set event parameter\n");
		return -1;
	}

	if (evi_param_set_str(evi_sess_sid_p, sess_id) < 0) {
		LM_ERR("cannot set event parameter\n");
		return -1;
	}
	if (evi_param_set_str(evi_sess_types_p, accept_types) < 0) {
		LM_ERR("cannot set event parameter\n");
		return -1;
	}

	if (evi_raise_event(evi_sess_new_id, evi_sess_params) < 0) {
		LM_ERR("cannot raise event\n");
		return -1;
	}

	return 0;
}

static int raise_sess_end_event(str *sess_id)
{
	if (evi_param_set_str(evi_sess_sid_p, sess_id) < 0) {
		LM_ERR("cannot set event parameter\n");
		return -1;
	}

	if (evi_raise_event(evi_sess_end_id, evi_sess_params) < 0) {
		LM_ERR("cannot raise event\n");
		return -1;
	}

	return 0;
}

static int raise_msg_rcv_event(str *sess_id, str *ctype, str *body)
{
	if (evi_param_set_str(evi_msg_rcv_sid_p, sess_id) < 0) {
		LM_ERR("cannot set event parameter\n");
		return -1;
	}
	if (evi_param_set_str(evi_msg_rcv_ctype_p, ctype) < 0) {
		LM_ERR("cannot set event parameter\n");
		return -1;
	}
	if (evi_param_set_str(evi_msg_rcv_body_p, body) < 0) {
		LM_ERR("cannot set event parameter\n");
		return -1;
	}

	if (evi_raise_event(evi_msg_rcv_id, evi_msg_rcv_params) < 0) {
		LM_ERR("cannot raise event\n");
		return -1;
	}

	return 0;
}

static int raise_report_event(str *sess_id, str *msgid, str *status, str *brange)
{
	if (evi_param_set_str(evi_report_sid_p, sess_id) < 0) {
		LM_ERR("cannot set event parameter\n");
		return -1;
	}
	if (msgid && evi_param_set_str(evi_report_msgid_p, msgid) < 0) {
		LM_ERR("cannot set event parameter\n");
		return -1;
	}
	if (evi_param_set_str(evi_report_status_p, status) < 0) {
		LM_ERR("cannot set event parameter\n");
		return -1;
	}
	if (brange && evi_param_set_str(evi_report_brange_p, brange) < 0) {
		LM_ERR("cannot set event parameter\n");
		return -1;
	}

	if (evi_raise_event(evi_report_id, evi_report_params) < 0) {
		LM_ERR("cannot raise event\n");
		return -1;
	}

	return 0;
}

static int b2b_notify_request(int etype, struct sip_msg *msg, str *key,
	void *param, int flags)
{
	struct msrpua_session *sess = (struct msrpua_session *)param;
	unsigned int hentry;
	str sess_id, accept_types;
	struct msrp_ua_notify_params cb_params = {};
	struct msrp_ua_handler hdl = {};
	int raise_ev = 0;
	str body;

	hentry = hash_entry(msrpua_sessions, sess->session_id);
	hash_lock(msrpua_sessions, hentry);

	LM_DBG("Received request [%.*s] for session [%.*s]\n", msg->REQ_METHOD_S.len,
		msg->REQ_METHOD_S.s, sess->session_id.len, sess->session_id.s);

	switch (msg->REQ_METHOD) {
	case METHOD_INVITE:
		if (get_body(msg, &body) == 0 && body.len == 0) {
			/* no SDP -> late negociation */

			if (msrpua_update_send_200ok(sess, etype) < 0)
				LM_ERR("Failed to send 200 OK on reInvite with no SDP\n");
		} else {
			if (msrpua_update_session(sess, msg, etype, 1) < 0)
				LM_ERR("Failed to update session on reInvite\n");
		}

		hash_unlock(msrpua_sessions, hentry);
		break;
	case METHOD_ACK:
		if (!(flags & B2B_NOTIFY_FL_ACK_NEG) &&
			/* ACK for initial INVITE */
			sess->sdp_sess_vers == sess->sdp_sess_id) {
			if (pkg_str_dup(&sess_id, &sess->session_id) < 0) {
				LM_ERR("out of pkg memory\n");
				return 0;
			}
			if (pkg_str_dup(&accept_types, &sess->peer_accept_types) < 0) {
				LM_ERR("out of pkg memory\n");
				pkg_free(sess_id.s);
				return 0;
			}

			sess->dlg_state = MSRPUA_DLG_EST;
			if (max_duration)
				sess->lifetime = max_duration + get_ticks();
			else
				sess->lifetime = 0;

			if (sess->hdl.name) {
				cb_params.event = MSRP_UA_SESS_ESTABLISHED;
				cb_params.msg = msg;
				cb_params.accept_types = &accept_types;
				cb_params.session_id = &sess_id;
				hdl = sess->hdl;
			}

			hash_unlock(msrpua_sessions, hentry);

			if (!cb_params.event) {
				if (raise_sess_new_event(msg, &sess_id, &sess->ruri,
					&accept_types) < 0)
					LM_ERR("Failed to raise session new event on ACK\n");
			} else {
				hdl.notify_cb(&cb_params, hdl.param);
			}

			/* we only needed the ruri for the E_MSRP_SESSION_NEW event params */
			shm_free(sess->ruri.s);
			sess->ruri.s = NULL;

			pkg_free(sess_id.s);
			pkg_free(accept_types.s);
		} else if (!(flags & B2B_NOTIFY_FL_ACK_NEG)) {
			/* ACK for reINVITE */

			if (get_body(msg, &body) == 0 && body.len == 0) {
				/* no SDP -> no late negociation, just update state */
				sess->dlg_state = MSRPUA_DLG_EST;
			} else {
				/* ACK with SDP -> update session */
				if (msrpua_update_session(sess, msg, etype, 0) < 0)
					LM_ERR("Failed to update session on ACK for reInvite\n");

				sess->dlg_state = MSRPUA_DLG_EST;
			}

			hash_unlock(msrpua_sessions, hentry);
		} else {
			hash_unlock(msrpua_sessions, hentry);
		}
		break;
	case METHOD_CANCEL:
		if (msrpua_b2b_reply(etype, key, METHOD_INVITE,
			487, &str_init("Request Terminated"), NULL) < 0)
			LM_ERR("Failed to send error reply\n");

		if (sess->sdp_sess_vers == sess->sdp_sess_id) {
			/* CANCEL for initial INVITE */
			if (sess->hdl.name) {
				if (pkg_str_dup(&sess_id, &sess->session_id) < 0) {
					LM_ERR("out of pkg memory\n");
					return 0;
				}

				cb_params.event = MSRP_UA_SESS_FAILED;
				cb_params.session_id = &sess_id;
				cb_params.msg = msg;
				hdl = sess->hdl;
			}

			msrpua_delete_session(sess);
		}

		hash_unlock(msrpua_sessions, hentry);

		if (cb_params.event) {
			hdl.notify_cb(&cb_params, hdl.param);
			pkg_free(sess_id.s);
		}

		break;
	case METHOD_BYE:
		if (msrpua_b2b_reply(etype, key, METHOD_BYE,
			200, &str_init("OK"), NULL) < 0)
			LM_ERR("Failed to send reply\n");

		if (pkg_str_dup(&sess_id, &sess->session_id) < 0) {
			LM_ERR("out of pkg memory\n");
			return 0;
		}

		if (sess->dlg_state == MSRPUA_DLG_CONF) {
			/* should be a UAS session */
			if (sess->hdl.name) {
				cb_params.event = MSRP_UA_SESS_FAILED;
				cb_params.session_id = &sess_id;
				cb_params.msg = msg;
				hdl = sess->hdl;
			}
		} else {  /* MSRPUA_DLG_EST */
			if (sess->hdl.name) {
				cb_params.event = MSRP_UA_SESS_TERMINATED;
				cb_params.session_id = &sess_id;
				cb_params.msg = msg;
				hdl = sess->hdl;
			} else  {
				raise_ev = 1;
			}
		}

		msrpua_delete_session(sess);
		hash_unlock(msrpua_sessions, hentry);

		if (raise_ev) {
			if (raise_sess_end_event(&sess_id) < 0)
				LM_ERR("Failed to raise session end event on BYE\n");

			pkg_free(sess_id.s);
		} else if (cb_params.event) {
			hdl.notify_cb(&cb_params, hdl.param);
			pkg_free(sess_id.s);
		}

		break;
	}

	return 0;
}

static int msrpua_send_message(str *sess_id, str *mime, str *body,
	enum msrp_failure_report_type failure_report, int success_report);

static int b2b_notify_reply(int etype, struct sip_msg *msg, str *key,
	void *param, int flags)
{
	struct msrpua_session *sess = (struct msrpua_session *)param;
	unsigned int hentry;
	str peer_accept_types;
	str peer_path;
	str sess_id;
	struct msrp_ua_notify_params cb_params = {};
	struct msrp_ua_handler hdl = {};
	int len;

	hentry = hash_entry(msrpua_sessions, sess->session_id);
	hash_lock(msrpua_sessions, hentry);

	LM_DBG("Received reply [%d] for session [%.*s]\n", msg->REPLY_STATUS,
		sess->session_id.len, sess->session_id.s);

	if (msg->REPLY_STATUS < 200) {
		hash_unlock(msrpua_sessions, hentry);
		return 0;
	}

	if (sess->dlg_state == MSRPUA_DLG_TERM) {
		LM_DBG("Reply for terminated session, deleting entry\n");
		msrpua_delete_session(sess);

		hash_unlock(msrpua_sessions, hentry);
		return 0;
	}

	if (etype == B2B_CLIENT) {
		if (msg->REPLY_STATUS >= 300) {
			if (sess->hdl.name) {
				if (pkg_str_dup(&sess_id, &sess->session_id) < 0) {
					LM_ERR("out of pkg memory\n");
					return 0;
				}

				cb_params.event = MSRP_UA_SESS_FAILED;
				cb_params.msg = msg;
				cb_params.session_id = &sess_id;
				hdl = sess->hdl;
			}

			msrpua_delete_session(sess);
			hash_unlock(msrpua_sessions, hentry);

			if (cb_params.event) {
				hdl.notify_cb(&cb_params, hdl.param);
				pkg_free(sess_id.s);
			}
		} else { /* 2xx reply */
			if (pkg_str_dup(&sess_id, &sess->session_id) < 0) {
				LM_ERR("out of pkg memory\n");
				goto error;
			}

			if (get_sdp_peer_info(msg, &peer_accept_types, &peer_path) < 0) {
				LM_ERR("Failed to get peer info from SDP\n");
				goto error;
			}

			/* match at least one content type from our accept_types
			 * with the peer's accept_types */
			if (!check_offer_types(&sess->accept_types, &peer_accept_types)) {
				LM_ERR("Cannot understand any content type received in the offer\n");
				goto error;
			}

			len = relay_uri_str.s ? peer_path.len + sess->use_path.len + 1 :
				peer_path.len;

			sess->peer_path.s = shm_malloc(len);
			if (!sess->peer_path.s) {
				LM_ERR("no more shm memory\n");
				goto error;
			}

			if (relay_uri_str.s) {
				memcpy(sess->peer_path.s, sess->use_path.s, sess->use_path.len);
				sess->peer_path.s[sess->use_path.len] = ' ';
				memcpy(sess->peer_path.s + sess->use_path.len + 1,
					peer_path.s, peer_path.len);
			} else {
				memcpy(sess->peer_path.s, peer_path.s, peer_path.len);
			}

			sess->peer_path.len = len;

			sess->peer_path_parsed = parse_msrp_path_shm(&sess->peer_path);
			if (!sess->peer_path_parsed ) {
				LM_ERR("Failed to parse MSRP peer path\n");
				goto error;
			}

			if (msrpua_b2b_request(etype, &sess->b2b_key, &str_init("ACK")) < 0) {
				LM_ERR("Failed to send ACK for 200 OK\n");
				goto error;
			}

			sess->dlg_state = MSRPUA_DLG_EST;
			if (max_duration)
				sess->lifetime = max_duration + get_ticks();
			else
				sess->lifetime = 0;

			if (sess->hdl.name) {
				cb_params.event = MSRP_UA_SESS_ESTABLISHED;
				cb_params.msg = msg;
				cb_params.accept_types = &peer_accept_types;
				cb_params.session_id = &sess_id;
				hdl = sess->hdl;
			}

			hash_unlock(msrpua_sessions, hentry);

			/* the initiating endpoint must issue a SEND request immediately */
			if (msrpua_send_message(&sess_id, NULL, NULL,
				MSRP_FAILURE_REPORT_NO, 0) < 0) {
				LM_ERR("Failed to send empty initial message\n");
				hash_lock(msrpua_sessions, hentry);
				goto error;
			}

			if (!cb_params.event) {
				if (raise_sess_new_event(msg, &sess_id, &sess->ruri,
					&peer_accept_types) < 0)
					LM_ERR("Failed to raise session new event on ACK\n");
			} else {
				hdl.notify_cb(&cb_params, hdl.param);
			}

			/* we only needed the ruri for the E_MSRP_SESSION_NEW event params */
			shm_free(sess->ruri.s);
			sess->ruri.s = NULL;

			pkg_free(sess_id.s);
		}
	}

	return 0;
error:
	if (msrpua_b2b_request(etype, &sess->b2b_key, &str_init("BYE")) < 0)
		LM_ERR("Failed to send BYE on error\n");

	if (sess->hdl.name && sess_id.s) {
		cb_params.event = MSRP_UA_SESS_FAILED;
		cb_params.msg = msg;
		cb_params.session_id = &sess_id;
		hdl = sess->hdl;
	}

	sess->dlg_state = MSRPUA_DLG_TERM;
	sess->lifetime = MSRPUA_SESS_DEL_TOUT + get_ticks();

	hash_unlock(msrpua_sessions, hentry);

	if (cb_params.event)
		hdl.notify_cb(&cb_params, hdl.param);

	if (sess_id.s)
		pkg_free(sess_id.s);

	return -1;
}

static int b2b_server_notify(struct sip_msg *msg, str *key, int type,
		str *logic_key, void *param, int flags)
{
	if (type == B2B_REPLY)
		return b2b_notify_reply(B2B_SERVER, msg, key, param, flags);
	else
		return b2b_notify_request(B2B_SERVER, msg, key, param, flags);
}

static int b2b_client_notify(struct sip_msg *msg, str *key, int type,
		str *logic_key, void *param, int flags)
{
	if (type == B2B_REPLY)
		return b2b_notify_reply(B2B_CLIENT, msg, key, param, flags);
	else
		return b2b_notify_request(B2B_CLIENT, msg, key, param, flags);
}

static inline void msrpua_gen_id(char *dest, str *src1, str *src2)
{
	str md5_src[5];
	int l;
	int n = 4;

	md5_src[0].s = int2str(time(NULL), &l);
	md5_src[0].len = l;
	md5_src[1].s = int2str(rand(), &l);
	md5_src[1].len = l;
	md5_src[2].s = int2str(rand(), &l);
	md5_src[2].len = l;
	md5_src[3] = *src1;

	if (src2) {
		n = 5;
		md5_src[4] = *src2;
	}

	MD5StringArray(dest, md5_src, n);
}

/* if successful, returns with the session lock aquired */
static struct msrpua_session *new_msrpua_session(int b2b_type, str *id_src1,
	str *id_src2, str *ruri, str *accept_types, struct msrp_ua_handler *hdl)
{
	unsigned int hentry;
	void **val;
	struct msrpua_session *sess;

	sess = shm_malloc(sizeof *sess + MD5_LEN + B2B_MAX_KEY_SIZE +
		accept_types->len);
	if (!sess) {
		LM_ERR("no more shm memory\n");
		return NULL;
	}
	memset(sess, 0, sizeof *sess);

	sess->session_id.s = (char*)(sess + 1);
	sess->session_id.len = MD5_LEN;
	msrpua_gen_id(sess->session_id.s, id_src1, id_src2);

	sess->accept_types.s = (char*)(sess + 1) + MD5_LEN + B2B_MAX_KEY_SIZE;
	sess->accept_types.len = accept_types->len;
	memcpy(sess->accept_types.s, accept_types->s, accept_types->len);

	sess->b2b_type = b2b_type;
	sess->lifetime = MSRPUA_SESS_SETUP_TOUT + get_ticks();
	sess->dlg_state = MSRPUA_DLG_NEW;

	if (shm_str_dup(&sess->ruri, ruri) < 0)
		goto error;

	hentry = hash_entry(msrpua_sessions, sess->session_id);
	hash_lock(msrpua_sessions, hentry);

	val = hash_get(msrpua_sessions, hentry, sess->session_id);
	if (!val) {
		hash_unlock(msrpua_sessions, hentry);
		LM_ERR("Failed to allocate new hash entry\n");
		goto error;
	}
	if (*val != NULL) {
		hash_unlock(msrpua_sessions, hentry);
		LM_ERR("Generated duplicate session-id\n");
		goto error;
	}
	*val = sess;

	if (hdl)
		sess->hdl = *hdl;

	LM_DBG("New MSRP UA session [%.*s] type: %d\n",
		sess->session_id.len, sess->session_id.s, b2b_type);

	return sess;
error:
	if (sess->ruri.s)
		shm_free(sess->ruri.s);
	shm_free(sess);
	return NULL;
}

static int init_msrpua_session(struct msrpua_session *sess, str *b2b_key,
	str *peer_path, str *peer_accept_types)
{
	sess->b2b_key.s = (char*)(sess + 1) + MD5_LEN;
	sess->b2b_key.len = b2b_key->len;
	memcpy(sess->b2b_key.s, b2b_key->s, b2b_key->len);

	if (peer_path) {
		if (shm_str_dup(&sess->peer_path, peer_path) < 0)
			return -1;

		if (!relay_uri_str.s) {
			sess->peer_path_parsed = parse_msrp_path_shm(&sess->peer_path);
			if (!sess->peer_path_parsed ) {
				LM_ERR("Failed to parse MSRP peer path\n");
				return -1;
			}
		}
	}

	if (peer_accept_types &&
		shm_str_dup(&sess->peer_accept_types, peer_accept_types) < 0)
		return -1;

	return 0;
}

static str *msrpua_build_auth_hdr(struct msrpua_session *sess,
	struct msrp_msg *rpl)
{
	str *buf;
	struct authenticate_body *auth_body = NULL;
	struct uac_credential *crd;
	struct digest_auth_response response;
	str _;
	static struct authenticate_nc_cnonce auth_nc_cnonce;

	if (!rpl->www_authenticate) {
		LM_ERR("WWW-Authenticate header missing\n");
		return NULL;
	}

	if (parse_authenticate_header(rpl->www_authenticate,
		DAUTH_AHFM_MSKSUP(ALG_MD5), &auth_body) < 0) {
		LM_ERR("Unable to extract authentication info\n");
		return NULL;
	}

	if ((auth_body->flags & QOP_AUTH_INT)) {
		LM_ERR("Unexpected qop value for MSRP:'auth-int'\n");
		return NULL;
	}

	crd = uac_auth_api._lookup_realm(&auth_body->realm);
	if (!crd) {
		LM_DBG("no credential for realm \"%.*s\"\n",
			auth_body->realm.len, auth_body->realm.s);
		return NULL;
	}

	if (uac_auth_api._do_uac_auth(&_, &str_init("AUTH"), &relay_uri.whole,
	    crd, auth_body, &auth_nc_cnonce, &response) != 0) {
		LM_ERR("Failed in do_uac_auth()\n");
		return NULL;
	}

	buf = uac_auth_api._build_authorization_hdr(401, &relay_uri.whole,
		crd, auth_body, &auth_nc_cnonce, &response);
	if (!buf) {
		LM_ERR("failed to build authorization hdr\n");
		return NULL;
	}

	/* msrp_api.send_request() will add the CRLF itself */
	buf->len -= CRLF_LEN;

	return buf;
}

int msrpua_send_auth(struct msrpua_session *sess, void *init_params,
	struct msrp_msg *rpl)
{
	str from = STR_NULL;
	char *p;
	str *auth_hdr = NULL;
	int hdrs_no = 0;

	from.len = my_msrp_uri.whole.len + 1 + sess->session_id.len;
	from.s = pkg_malloc(from.len);
	if (!from.s) {
		LM_ERR("no more pkg memory\n");
		goto error;
	}

	/* build From-Path with current session_id */
	p = from.s;
	append_string(p, my_msrp_uri.whole.s,
		my_msrp_uri.whole.len - my_msrp_uri.params.len - 1);
	*(p++) = '/';
	append_string(p, sess->session_id.s, sess->session_id.len);
	*(p++) = ';';
	append_string(p, my_msrp_uri.params.s, my_msrp_uri.params.len);

	if (rpl) {
		auth_hdr = msrpua_build_auth_hdr(sess, rpl);
		if (!auth_hdr) {
			LM_ERR("Failed to build Authorization header\n");
			goto error;
		}
		hdrs_no = 1;
	}

	if (msrp_api.send_request(msrp_hdl, MSRP_METHOD_AUTH, &from, &relay_uri,
		msrp_sock, NULL, NULL, NULL, auth_hdr, hdrs_no, '$', init_params) < 0) {
		LM_ERR("Failed to send MSRP request\n");
		goto error;
	}

	if (auth_hdr)
		pkg_free(auth_hdr->s);
	if (from.s)
		pkg_free(from.s);

	return 0;
error:
	if (auth_hdr)
		pkg_free(auth_hdr->s);
	if (from.s)
		pkg_free(from.s);
	return -1;
}



static int msrpua_start_uas(struct msrpua_session *sess)
{
	unsigned int hentry;
	int n;
	str *sdp = NULL;

	hentry = hash_entry(msrpua_sessions, sess->session_id);

	lock_get(sdp_id_lock);
	n = (*next_sdp_id)++;
	lock_release(sdp_id_lock);

	sess->sdp_sess_id = n;
	sess->sdp_sess_vers = n;

	sdp = msrpua_build_sdp(sess, &sess->accept_types);
	if (!sdp) {
		LM_ERR("Failed to build SDP answer\n");
		goto err_reply;
	}

	if (relay_uri_str.s &&
		update_peer_path(sess) < 0) {
		LM_ERR("Failed to update peer path with the relay URI\n");
		goto err_reply;
	}

	if (msrpua_b2b_reply(B2B_SERVER, &sess->b2b_key, METHOD_INVITE,
		200, &str_init("OK"), sdp) < 0) {
		LM_ERR("Failed to send 200 OK\n");
		goto err;
	}

	sess->dlg_state = MSRPUA_DLG_CONF;

	pkg_free(sdp->s);

	hash_unlock(msrpua_sessions, hentry);
	return 0;

err_reply:
	if (msrpua_b2b_reply(B2B_SERVER, &sess->b2b_key, METHOD_INVITE,
		500, &str_init("Internal Server Error"), NULL) < 0)
		LM_ERR("Failed to send error reply\n");
err:
	msrpua_delete_session(sess);
	hash_unlock(msrpua_sessions, hentry);

	if (sdp)
		pkg_free(sdp->s);
	return -1;
}

static int msrpua_init_uas(struct sip_msg *msg, str *accept_types,
	struct msrp_ua_handler *hdl)
{
	str *b2b_key = NULL;
	str contact;
	unsigned int hentry;
	struct msrpua_session *sess;
	struct uas_init_params *p = NULL;
	str peer_accept_types;
	str peer_path;
	int code;
	str reason;
	str callid;

	if (get_callid(msg, &callid) < 0) {
		LM_ERR("Failed to get Call-Id from message\n");
		return -1;
	}

	sess = new_msrpua_session(B2B_SERVER, &callid, NULL, GET_RURI(msg),
		accept_types, hdl);
	if (!sess) {
		LM_ERR("Failed to create new MSRP UA session\n");
		return -1;
	}

	hentry = hash_entry(msrpua_sessions, sess->session_id);

	if (adv_contact.s)
		contact = adv_contact;
	else
		contact.s = contact_builder(msg->rcv.bind_address, &contact.len);

	b2b_key = b2b_api.server_new(msg, &contact, b2b_server_notify,
		&msrpua_mod_name, NULL, NULL, sess, NULL);
	if (!b2b_key) {
		LM_ERR("failed to create new b2b server instance\n");
		goto err;
	}

	if (get_sdp_peer_info(msg, &peer_accept_types, &peer_path) < 0) {
		LM_ERR("Failed to get peer info from SDP\n");
		code = 488;
		reason = str_init(REASON_488_STR);
		goto err_reply;
	}

	/* match at least one content type from our accept_types 
	 * with the peer's accept_types */
	if (check_offer_types(accept_types, &peer_accept_types) < 0) {
		LM_ERR("Cannot understand any content type received in the offer\n");
		code = 488;
		reason = str_init(REASON_488_STR);
		goto err_reply;
	}

	if (init_msrpua_session(sess, b2b_key, &peer_path, &peer_accept_types) < 0) {
		LM_ERR("Failed to init MSRP UA session\n");
		code = 500;
		reason = str_init("Internal Server Error");
		goto err_reply;
	}

	if (relay_uri_str.s) {
		p = shm_malloc(sizeof *p);
		if (!p) {
			LM_ERR("no more shm memory\n");
			code = 500;
			reason = str_init("Internal Server Error");
			goto err_reply;
		}
		memset(p, 0, sizeof *p);

		p->sess = sess;

		if (msrpua_send_auth(sess, p, NULL) < 0) {
			LM_ERR("Failed to send AUTH request\n");
			code = 500;
			reason = str_init("Internal Server Error");
			goto err_reply;
		}

		hash_unlock(msrpua_sessions, hentry);

		pkg_free(b2b_key);
		return 0;
	}

	pkg_free(b2b_key);

	return msrpua_start_uas(sess);

err_reply:
	if (msrpua_b2b_reply(B2B_SERVER, b2b_key, METHOD_INVITE,
		code, &reason, NULL) < 0)
		LM_ERR("Failed to send error reply\n");
err:
	msrpua_delete_session(sess);
	hash_unlock(msrpua_sessions, hentry);

	if (b2b_key)
		pkg_free(b2b_key);
	if (p)
		shm_free(p);
	return -1;
}

static int msrpua_answer(struct sip_msg *msg, str *content_types)
{
	if (msrpua_init_uas(msg, content_types, NULL) < 0)
		return -1;
	else
		return 1;
}

int b2b_add_dlginfo(str* key, str* entity_key, int src, b2b_dlginfo_t* dlginfo,
	void *param)
{
	struct msrpua_session *sess = (struct msrpua_session *)param;
	sess->dlginfo = b2b_dup_dlginfo(dlginfo);
	if (!sess->dlginfo) {
		LM_ERR("could not duplicate b2be dialog info!\n");
		return -1;
	}
	return 0;
}

static int msrpua_start_uac(struct uac_init_params *params)
{
	str *b2b_key = NULL;
	client_info_t ci;
	static str method_invite = str_init("INVITE");
	unsigned int hentry;
	int n;
	str _ = STR_NULL;
	struct msrpua_session *sess = params->sess;

	hentry = hash_entry(msrpua_sessions, sess->session_id);

	memset(&ci, 0, sizeof ci);
	ci.method = method_invite;
	ci.to_uri = params->to_uri;
	ci.from_uri = params->from_uri;
	ci.req_uri = params->ruri;

	if (adv_contact.s) {
		ci.local_contact = adv_contact;
	} else {
		LM_ERR("'advertised_contact' parameter required\n");
		goto error;
	}

	lock_get(sdp_id_lock);
	n = (*next_sdp_id)++;
	lock_release(sdp_id_lock);

	sess->sdp_sess_id = n;
	sess->sdp_sess_vers = n;

	ci.body = msrpua_build_sdp(sess, &sess->accept_types);
	if (!ci.body) {
		LM_ERR("Failed to build SDP answer\n");
		goto error;
	}

	b2b_key = b2b_api.client_new(&ci, b2b_client_notify, b2b_add_dlginfo,
		&msrpua_mod_name, &_, NULL, sess, NULL);
	if (!b2b_key) {
		LM_ERR("failed to create new b2b client instance\n");
		goto error;
	}

	if (init_msrpua_session(sess, b2b_key, NULL, NULL) < 0) {
		LM_ERR("Failed to init MSRP UA session\n");
		goto error;
	}

	hash_unlock(msrpua_sessions, hentry);

	pkg_free(ci.body->s);
	pkg_free(b2b_key);

	return 0;
error:
	msrpua_delete_session(sess);

	hash_unlock(msrpua_sessions, hentry);

	if (b2b_key)
		pkg_free(b2b_key);
	if (ci.body)
		pkg_free(ci.body->s);
	return -1;
}

static int msrpua_init_uac(str *accept_types, str *from_uri, str *to_uri,
	str *ruri, struct msrp_ua_handler *hdl)
{
	struct uac_init_params params;
	struct uac_init_params *p = NULL;
	unsigned int hentry;
	struct msrpua_session *sess;

	sess = new_msrpua_session(B2B_CLIENT, from_uri, to_uri, ruri, accept_types,
		hdl);
	if (!sess) {
		LM_ERR("Failed to create new MSRP UA session\n");
		return -1;
	}

	if (relay_uri_str.s) {
		hentry = hash_entry(msrpua_sessions, sess->session_id);

		p = shm_malloc(sizeof *p + from_uri->len + to_uri->len + ruri->len);
		if (!p) {
			LM_ERR("no more shm memory\n");
			goto error;
		}
		memset(p, 0, sizeof *p);

		p->sess = sess;

		p->from_uri.s = (char *)(p + 1);
		p->from_uri.len = from_uri->len;
		memcpy(p->from_uri.s, from_uri->s, from_uri->len);

		p->to_uri.s = (char *)(p + 1) + from_uri->len;
		p->to_uri.len = to_uri->len;
		memcpy(p->to_uri.s, to_uri->s, to_uri->len);

		p->ruri.s = (char *)(p + 1) + from_uri->len + to_uri->len;
		p->ruri.len = ruri->len;
		memcpy(p->ruri.s, ruri->s, ruri->len);

		if (msrpua_send_auth(sess, p, NULL) < 0) {
			LM_ERR("Failed to send AUTH request\n");
			goto error;

		}

		hash_unlock(msrpua_sessions, hentry);
		return 0;
	}

	params.sess = sess;
	params.from_uri = *from_uri;
	params.to_uri = *to_uri;
	params.ruri = *ruri;

	return msrpua_start_uac(&params);

error:
	msrpua_delete_session(sess);
	hash_unlock(msrpua_sessions, hentry);
	if (p)
		shm_free(p);
	return -1;
}

static int msrpua_end_session(str *session_id)
{
	unsigned int hentry;
	struct msrpua_session *sess;
	void **val;
	int rc = -1;

	hentry = hash_entry(msrpua_sessions, *session_id);
	hash_lock(msrpua_sessions, hentry);

	val = hash_find(msrpua_sessions, hentry, *session_id);
	if (!val) {
		LM_ERR("session [%.*s] does not exist\n",
			session_id->len, session_id->s);
		rc = 1;
		goto error;
	}
	sess = *val;

	if (sess->dlg_state == MSRPUA_DLG_TERM) {
		hash_unlock(msrpua_sessions, hentry);
		return 0;
	}

	if (sess->dlg_state == MSRPUA_DLG_NEW) {
		if (msrpua_b2b_request(sess->b2b_type, &sess->b2b_key,
			&str_init("CANCEL")) < 0) {
			LM_ERR("Failed to send CANCEL\n");
			rc = -1;
			goto error;
		}
	} else {
		if (msrpua_b2b_request(sess->b2b_type, &sess->b2b_key,
			&str_init("BYE")) < 0) {
			LM_ERR("Failed to send BYE\n");
			rc = -1;
			goto error;
		}
	}

	sess->dlg_state = MSRPUA_DLG_TERM;
	sess->lifetime = MSRPUA_SESS_DEL_TOUT + get_ticks();

	hash_unlock(msrpua_sessions, hentry);
	return 0;
error:
	hash_unlock(msrpua_sessions, hentry);
	return rc;
}

#define REPORT_STATUS_OK "000 200 OK"

static int handle_msrp_send(struct msrp_msg *req, struct msrpua_session *sess,
	unsigned int hentry, int t_report)
{
	struct msrp_url *to = (struct msrp_url *)req->to_path->parsed;
	struct msrp_ua_handler hdl;
	int run_cb = 0;
	int rc = 0;

	if (req->body.len && req->content_type &&
		!match_mime_with_list(&req->content_type->body, &sess->accept_types)) {
		LM_DBG("Unacceptable content type: %.*s\n",
			req->content_type->body.len, req->content_type->body.s);
		if (t_report && msrp_api.send_reply(msrp_hdl, req, 415, NULL,NULL,0) < 0)
			LM_ERR("Failed to send reply\n");

		hash_unlock(msrpua_sessions, hentry);
		return -1;
	}

	if (sess->b2b_type == B2B_SERVER)
		sess->to_su = req->rcv.src_su;

	if (sess->hdl.name) {
		run_cb = 1;
		hdl = sess->hdl;
	}

	hash_unlock(msrpua_sessions, hentry);

	if (t_report && msrp_api.send_reply(msrp_hdl, req, 200, &str_init("OK"),
		NULL, 0) < 0) {
		LM_ERR("Failed to send reply\n");
		return -1;
	}

	if (req->body.len) {
		if (run_cb) {
			rc = hdl.msrp_req_cb(req, hdl.param);
		} else {
			if (raise_msg_rcv_event(&to->session, &req->content_type->body,
				&req->body) < 0) {
				LM_ERR("Failed to raise message received event\n");
				return -1;
			}
		}
	}

	if (rc == 0 && req->success_report && str_match((&str_init("yes")),
		&req->success_report->body) && msrp_api.send_report(msrp_hdl,
		&str_init(REPORT_STATUS_OK), req, NULL) < 0) {
		LM_ERR("Failed to send REPORT\n");
		return -1;
	}

	return 0;
}

static int handle_msrp_report(struct msrp_msg *req, struct msrpua_session *sess,
	unsigned int hentry)
{
	struct msrp_url *to = (struct msrp_url *)req->to_path->parsed;
	struct msrp_ua_handler hdl;
	int run_cb = 0;
	str status_str;

	if (sess->hdl.name) {
		run_cb = 1;
		hdl = sess->hdl;
	}

	hash_unlock(msrpua_sessions, hentry);

	if (run_cb) {
		hdl.msrp_req_cb(req, hdl.param);
	} else {
		status_str.s = req->status->body.s + 4; /* skip the "000" namespace */
		status_str.len = req->status->body.len - 4;
		if (raise_report_event(&to->session, &req->message_id->body,
			&status_str, &req->byte_range->body) < 0) {
			LM_ERR("Failed to raise report received event\n");
			return -1;
		}
	}

	return 0;
}

static int handle_msrp_request(struct msrp_msg *req, void *hdl_param)
{
	unsigned int hentry;
	struct msrpua_session *sess;
	void **val;
	struct msrp_url *to;
	int t_report = 0;

	LM_DBG("Received MSRP request [%.*s]\n", req->fl.u.request.method.len,
		req->fl.u.request.method.s);

	if (req->fl.u.request.method_id == MSRP_METHOD_REPORT) {
		t_report = 0;
	} else if (req->fl.u.request.method_id == MSRP_METHOD_SEND) {
		if (!req->failure_report || !str_match((&str_init("no")),
			&req->failure_report->body))
			t_report = 1;
	} else {
		LM_DBG("Unknown MSRP method\n");
		return 0;
	}

	to = (struct msrp_url *)req->to_path->parsed;
	hentry = hash_entry(msrpua_sessions, to->session);

	hash_lock(msrpua_sessions, hentry);

	val = hash_find(msrpua_sessions, hentry, to->session);
	if (!val) {
		hash_unlock(msrpua_sessions, hentry);
		LM_ERR("Invalid URI, session does not exist\n");

		if (t_report && msrp_api.send_reply(msrp_hdl, req, 481, NULL,NULL,0) < 0)
			LM_ERR("Failed to send reply\n");

		return -1;
	}
	sess = *val;

	if (req->fl.u.request.method_id == MSRP_METHOD_REPORT)
		return handle_msrp_report(req, sess, hentry);
	else
		return handle_msrp_send(req, sess, hentry, t_report);
}

static int handle_msrp_reply(struct msrp_msg *rpl, struct msrp_cell *tran,
	void *trans_param, void *hdl_param)
{
	struct msrpua_session *sess;
	unsigned int hentry;
	struct msrp_ua_handler hdl = {};
	int run_cb = 0;
	struct uac_init_params *uac_params = NULL;
	struct msrpua_trans_param *params;
	str sess_id;
	str status_str;
	struct msrp_ua_notify_params cb_params = {};

	if (rpl)
		LM_DBG("Received MSRP reply [%d %.*s]\n", rpl->fl.u.reply.status_no,
			rpl->fl.u.reply.reason.len, rpl->fl.u.reply.reason.s);
	else
		LM_DBG("Timeout for ident=%.*s\n", tran->ident.len, tran->ident.s);

	if (tran->method_id == MSRP_METHOD_AUTH) {
		/* trans_param can be either struct uac_init_params or
		 * struct uas_init_params but the first member is always
		 * a struct msrpua_session pointer */
		uac_params = (struct uac_init_params *)trans_param;
		sess = uac_params->sess;

		hentry = hash_entry(msrpua_sessions, sess->session_id);
		hash_lock(msrpua_sessions, hentry);

		if (!rpl)
			goto err_failed;

		if (rpl->fl.u.reply.status_no == 401) {
			if (msrpua_send_auth(sess, trans_param, rpl) < 0) {
				LM_ERR("Failed to send AUTH request\n");
				goto err_failed;
			}

			hash_unlock(msrpua_sessions, hentry);
		} else if (rpl->fl.u.reply.status_no == 200) {
			if (!rpl->use_path) {
				LM_ERR("'Use-Path' header is missing from 200 OK\n");
				goto err_failed;
			}
			if (shm_str_dup(&sess->use_path, &rpl->use_path->body) < 0) {
				LM_ERR("no more shm memory\n");
				goto err_failed;
			}

			if (sess->b2b_type == B2B_SERVER)
				msrpua_start_uas(sess);
			else
				msrpua_start_uac(uac_params);

			/* entry unlocked by msrpua_start_uac/uas() */

			shm_free(uac_params);
		} else {  /* other negative replies */
			goto err_failed;
		}
	} else {
		params = (struct msrpua_trans_param *)trans_param;

		if (!rpl && !params->timeout) {
			/* not interested in the transaction timeout */
			shm_free(params);
			return 0;
		}

		sess = params->sess;
		hentry = hash_entry(msrpua_sessions, sess->session_id);
		hash_lock(msrpua_sessions, hentry);

		if (sess->hdl.name) {
			run_cb = 1;
			hdl = sess->hdl;
		} else if (!rpl || rpl->fl.u.reply.status_no != 200) {
			if (pkg_str_dup(&sess_id, &sess->session_id) < 0) {
				LM_ERR("out of pkg memory\n");
				shm_free(params);
				return -1;
			}

			if (rpl) {
				status_str.len = rpl->fl.u.reply.status.len +
					rpl->fl.u.reply.reason.len;
				status_str.s = pkg_malloc(status_str.len + 1);
				if (!status_str.s) {
					LM_ERR("no more pkg memory\n");
					pkg_free(sess_id.s);
					shm_free(params);
					return -1;
				}
				memcpy(status_str.s, rpl->fl.u.reply.status.s,
					rpl->fl.u.reply.status.len);
				if (rpl->fl.u.reply.reason.len) {
					status_str.s[rpl->fl.u.reply.status.len] = ' ';
					memcpy(status_str.s + rpl->fl.u.reply.status.len + 1,
						rpl->fl.u.reply.reason.s, rpl->fl.u.reply.reason.len);
				}
			} else {
				status_str = str_init("408");
			}
		}

		hash_unlock(msrpua_sessions, hentry);

		if (run_cb) {
			hdl.msrp_rpl_cb(rpl, hdl.param);
		} else if (!rpl || rpl->fl.u.reply.status_no != 200) {
			if (raise_report_event(&sess_id, &params->message_id, &status_str,
				&params->byte_range) < 0) {
				LM_ERR("Failed to raise report received event\n");
				pkg_free(sess_id.s);
				if (rpl)
					pkg_free(status_str.s);
				shm_free(params);
				return -1;
			}

			pkg_free(sess_id.s);
			if (rpl)
				pkg_free(status_str.s);
		}

		shm_free(params);
	}

	return 0;

err_failed:
	if (sess->hdl.name) {
		if (pkg_str_dup(&sess_id, &sess->session_id) < 0) {
			LM_ERR("out of pkg memory\n");
			goto err_del;
		}

		cb_params.event = MSRP_UA_SESS_FAILED;
		cb_params.session_id = &sess_id;
		hdl = sess->hdl;
	}

err_del:
	msrpua_delete_session(sess);
	hash_unlock(msrpua_sessions, hentry);

	if (cb_params.event) {
		hdl.notify_cb(&cb_params, hdl.param);
		pkg_free(sess_id.s);
	}

	shm_free(uac_params);

	return -1;
}

#define MESSAGE_ID_PREFIX "Message-ID: "
#define MESSAGE_ID_PREFIX_LEN (sizeof(MESSAGE_ID_PREFIX) - 1)
#define BYTE_RANGE_PREFIX "Byte-Range: 1-"
#define BYTE_RANGE_PREFIX_LEN (sizeof(BYTE_RANGE_PREFIX) - 1)

#define FAILURE_REPORT_NO_HDR "Failure-Report: no"
#define FAILURE_REPORT_PARTIAL_HDR "Failure-Report: partial"
#define SUCCESS_REPORT_YES_HDR "Success-Report: yes"

#define MSRP_HDRS_MAX_NO 4

static int msrpua_send_message(str *sess_id, str *mime, str *body,
	enum msrp_failure_report_type failure_report, int success_report)
{
	unsigned int hentry;
	struct msrpua_session *sess;
	struct msrpua_trans_param *trans_param;
	void **val;
	int rc = -1;
	int hdrs_no = 0;
	str from = {0};
	str hdrs[MSRP_HDRS_MAX_NO] = {{0}};
	char *p;
	str msgid;
	str blen;

	if (!mime || !body) {
		mime = NULL;
		body = NULL;
	}

	hentry = hash_entry(msrpua_sessions, *sess_id);
	hash_lock(msrpua_sessions, hentry);

	val = hash_find(msrpua_sessions, hentry, *sess_id);
	if (!val) {
		LM_ERR("session [%.*s] does not exist\n",
			sess_id->len, sess_id->s);
		rc = 1;
		goto error;
	}
	sess = *val;

	if (sess->dlg_state != MSRPUA_DLG_EST) {
		LM_ERR("Session not established yet\n");
		goto error;
	}

	from.len = my_msrp_uri.whole.len + 1 + sess->session_id.len;
	from.s = pkg_malloc(from.len);
	if (!from.s) {
		LM_ERR("no more pkg memory\n");
		goto error;
	}

	/* build From-Path with current session_id */
	p = from.s;
	append_string(p, my_msrp_uri.whole.s,
		my_msrp_uri.whole.len - my_msrp_uri.params.len - 1);
	*(p++) = '/';
	append_string(p, sess->session_id.s, sess->session_id.len);
	*(p++) = ';';
	append_string(p, my_msrp_uri.params.s, my_msrp_uri.params.len);

	/* Message-ID */
	hdrs[0].len = MESSAGE_ID_PREFIX_LEN + MD5_LEN;
	hdrs[0].s = pkg_malloc(hdrs[0].len);
	if (!hdrs[0].s) {
		LM_ERR("no more pkg memory\n");
		goto error;
	}

	p = hdrs[0].s;
	append_string(p, MESSAGE_ID_PREFIX, MESSAGE_ID_PREFIX_LEN);
	msrpua_gen_id(p, &sess->session_id, NULL);
	msgid.s = p;
	msgid.len = MD5_LEN;

	hdrs_no++;

	/* Byte-Range: 1-len/len */
	hdrs[1].len = BYTE_RANGE_PREFIX_LEN;
	if (body) {
		blen.s = int2str(body->len, &blen.len);
		hdrs[1].len += blen.len + 1 + blen.len;
	} else {
		blen = str_init("0");
		hdrs[1].len += 3;
	}
	hdrs[1].s = pkg_malloc(hdrs[1].len);
	if (!hdrs[1].s) {
		LM_ERR("no more pkg memory\n");
		goto error;
	}

	p = hdrs[1].s;
	append_string(p, BYTE_RANGE_PREFIX, BYTE_RANGE_PREFIX_LEN);
	append_string(p, blen.s, blen.len);
	*(p++) = '/';
	append_string(p, blen.s, blen.len);

	hdrs_no++;

	if (failure_report == MSRP_FAILURE_REPORT_NO)
		hdrs[hdrs_no++] = str_init(FAILURE_REPORT_NO_HDR);
	else if (failure_report == MSRP_FAILURE_REPORT_PARTIAL)
		hdrs[hdrs_no++] = str_init(FAILURE_REPORT_PARTIAL_HDR);

	if (success_report)
		hdrs[hdrs_no++] = str_init(SUCCESS_REPORT_YES_HDR);

	trans_param = shm_malloc(sizeof *trans_param + hdrs[0].len + hdrs[1].len);
	if (!trans_param) {
		LM_ERR("no more shm memory\n");
		goto error;
	}
	memset(trans_param, 0, sizeof *trans_param);

	trans_param->sess = sess;

	trans_param->message_id.s = (char *)(trans_param + 1);
	trans_param->message_id.len = msgid.len;
	memcpy(trans_param->message_id.s, msgid.s, msgid.len);
	trans_param->byte_range.s = (char *)(trans_param + 1) +
		trans_param->message_id.len;
	trans_param->byte_range.len = hdrs[1].len;
	memcpy(trans_param->byte_range.s, hdrs[1].s, hdrs[1].len);

	if (failure_report == MSRP_FAILURE_REPORT_YES)
		trans_param->timeout = 1;

	if (msrp_api.send_request(msrp_hdl, MSRP_METHOD_SEND, &from,
		sess->peer_path_parsed, msrp_sock, &sess->to_su, mime, body, hdrs,
		hdrs_no, '$', trans_param) < 0) {
		LM_ERR("Failed to send MSRP message\n");
		goto error;
	}

	pkg_free(from.s);
	pkg_free(hdrs[0].s);
	pkg_free(hdrs[1].s);

	hash_unlock(msrpua_sessions, hentry);
	return 0;
error:
	hash_unlock(msrpua_sessions, hentry);
	if (from.s)
		pkg_free(from.s);
	if (hdrs[0].s)
		pkg_free(hdrs[0].s);
	if (hdrs[1].s)
		pkg_free(hdrs[1].s);
	return rc;
}

mi_response_t *msrpua_mi_send_msg(const mi_params_t *params,
	struct mi_handler *_)
{
	str sess_id;
	str mime;
	str body;
	str failure_param, success_param;
	int failure_report, success_report;
	int rc;

	if (get_mi_string_param(params, "session_id", &sess_id.s, &sess_id.len) < 0)
		return init_mi_param_error();

	switch (try_get_mi_string_param(params, "mime", &mime.s, &mime.len)) {
		case 0:
			break;
		case -1:
			mime.s = NULL;
			break;
		default:
			return init_mi_param_error();
	}
	switch (try_get_mi_string_param(params, "body", &body.s, &body.len)) {
		case 0:
			break;
		case -1:
			body.s = NULL;
			break;
		default:
			return init_mi_param_error();
	}

	switch (try_get_mi_string_param(params, "failure_report",
		&failure_param.s, &failure_param.len)) {
		case 0:
			if (str_match((&str_init("no")), &failure_param))
				failure_report = MSRP_FAILURE_REPORT_NO;
			else if (str_match((&str_init("yes")), &failure_param))
				failure_report = MSRP_FAILURE_REPORT_YES;
			else if (str_match((&str_init("partial")), &failure_param))
				failure_report = MSRP_FAILURE_REPORT_PARTIAL;
			else
				return init_mi_error(500,
					MI_SSTR("Unacceptable value for Failure-Report"));

			break;
		case -1:
			failure_report = MSRP_FAILURE_REPORT_YES;
			break;
		default:
			return init_mi_param_error();
	}
	switch (try_get_mi_string_param(params, "success_report",
		&success_param.s, &success_param.len)) {
		case 0:
			if (str_match((&str_init("no")), &success_param))
				success_report = 0;
			else if (str_match((&str_init("yes")), &success_param))
				success_report = 1;
			else
				return init_mi_error(500,
					MI_SSTR("Unacceptable value for Success-Report"));

			break;
		case -1:
			success_report = 0;
			break;
		default:
			return init_mi_param_error();
	}

	rc = msrpua_send_message(&sess_id, mime.s ? &mime:NULL, body.s ? &body:NULL,
		failure_report, success_report);
	if (rc < 0)
		return init_mi_error(500, MI_SSTR("Failed to send message"));
	else if (rc == 1)
		return init_mi_error(404, MI_SSTR("Unknown session"));

	return init_mi_result_ok();
}

mi_response_t *msrpua_mi_end(const mi_params_t *params,
	struct mi_handler *_)
{
	str sess_id;
	int rc;

	if (get_mi_string_param(params, "session_id", &sess_id.s, &sess_id.len) < 0)
		return init_mi_param_error();

	rc = msrpua_end_session(&sess_id);
	if (rc < 0)
		return init_mi_error(500, MI_SSTR("Unable to end session"));
	else if (rc == 1)
		return init_mi_error(404, MI_SSTR("Unknown session"));

	return init_mi_result_ok();
}

struct mi_list_params {
	mi_item_t *resp_arr;
	int rc;
};

static int mi_print_session(void *param, str key, void *value)
{
	struct msrpua_session *sess = (struct msrpua_session *)value;
	struct mi_list_params *params = (struct mi_list_params *)param;
	mi_item_t *sess_obj;
	str hdl_str;

	sess_obj = add_mi_object(params->resp_arr, NULL, 0);
	if (!sess_obj) {
		params->rc = 1;
		return 1;
	}

	if (add_mi_string(sess_obj, MI_SSTR("session_id"),
		sess->session_id.s, sess->session_id.len) < 0) {
		params->rc = 1;
		return 1;
	}

	if (add_mi_string(sess_obj, MI_SSTR("b2b_key"),
		sess->b2b_key.s, sess->b2b_key.len) < 0) {
		params->rc = 1;
		return 1;
	}
	if (add_mi_string_fmt(sess_obj, MI_SSTR("type"),
		sess->b2b_type==B2B_SERVER ? "UAS" : "UAC") < 0) {
		params->rc = 1;
		return 1;
	}

	if (sess->hdl.name)
		hdl_str = *sess->hdl.name ;
	else
		hdl_str = str_init("msrp_ua");
	if (add_mi_string(sess_obj, MI_SSTR("handler"),
		hdl_str.s, hdl_str.len) < 0) {
		params->rc = 1;
		return 1;
	}

	if (add_mi_number(sess_obj, MI_SSTR("dlg_state"), sess->dlg_state) < 0) {
		params->rc = 1;
		return 1;
	}

	if (add_mi_string(sess_obj, MI_SSTR("peer_path"),
		sess->peer_path.s, sess->peer_path.len) < 0) {
		params->rc = 1;
		return 1;
	}

	if (add_mi_number(sess_obj, MI_SSTR("lifetime"),
		sess->lifetime - get_ticks()) < 0) {
		params->rc = 1;
		return 1;
	}

	return 0;
}

mi_response_t *msrpua_mi_list(const mi_params_t *_,
	struct mi_handler *__)
{
	mi_response_t *resp;
	struct mi_list_params params = {0};

	resp = init_mi_result_array(&params.resp_arr);
	if (!resp)
		return NULL;

	hash_for_each_locked(msrpua_sessions, mi_print_session, &params);
	if (params.rc != 0)
		goto error;

	return resp;
error:
	free_mi_response(resp);
	return NULL;
}

mi_response_t *msrpua_mi_start_session(const mi_params_t *params,
	struct mi_handler *_)
{
	str ct_types;
	str from_uri, to_uri, ruri;

	if (get_mi_string_param(params, "content_types", &ct_types.s,
		&ct_types.len) < 0)
		return init_mi_param_error();
	if (get_mi_string_param(params, "from_uri", &from_uri.s,
		&from_uri.len) < 0)
		return init_mi_param_error();
	if (get_mi_string_param(params, "to_uri", &to_uri.s,
		&to_uri.len) < 0)
		return init_mi_param_error();
	if (get_mi_string_param(params, "ruri", &ruri.s,
		&ruri.len) < 0)
		return init_mi_param_error();

	if (msrpua_init_uac(&ct_types, &from_uri, &to_uri, &ruri, NULL) < 0)
		return init_mi_error(500, MI_SSTR("Failed to start session"));

	return init_mi_result_ok();
}

static int timer_clean_session(void *param, str key, void *value)
{
	struct msrpua_session *sess = (struct msrpua_session *)value;
	str sess_id;
	int raise_ev = 0;
	struct msrp_ua_notify_params cb_params = {};
	struct msrp_ua_handler hdl = {};

	if (sess->lifetime > 0 && sess->lifetime < get_ticks()) {
		LM_DBG("Timeout for session [%.*s] in state [%d]\n",
			sess->session_id.len, sess->session_id.s, sess->dlg_state);

		if (sess->dlg_state == MSRPUA_DLG_NEW) {
			if (msrpua_b2b_request(sess->b2b_type, &sess->b2b_key,
				&str_init("CANCEL")) < 0)
				LM_ERR("Failed to send CANCEL on timeout\n");

			sess->dlg_state = MSRPUA_DLG_TERM;
			sess->lifetime = MSRPUA_SESS_DEL_TOUT + get_ticks();

			if (sess->hdl.name) {
				if (pkg_str_dup(&sess_id, &sess->session_id) < 0) {
					LM_ERR("no more pkg memory\n");
					goto del_session;
				}

				cb_params.event = MSRP_UA_SESS_FAILED;
				cb_params.session_id = &sess_id;
				hdl = sess->hdl;
			}

			goto end;
		} else if (sess->dlg_state < MSRPUA_DLG_TERM) {
			if (msrpua_b2b_request(sess->b2b_type, &sess->b2b_key,
				&str_init("BYE")) < 0) {
				LM_ERR("Failed to send BYE on timeout\n");
				goto del_session;
			}

			sess->dlg_state = MSRPUA_DLG_TERM;
			sess->lifetime = MSRPUA_SESS_DEL_TOUT + get_ticks();

			if (sess->dlg_state == MSRPUA_DLG_EST) {
				if (pkg_str_dup(&sess_id, &sess->session_id) < 0) {
					LM_ERR("no more pkg memory\n");
					goto del_session;
				}

				if (sess->hdl.name) {
					cb_params.event = MSRP_UA_SESS_TERMINATED;
					cb_params.session_id = &sess_id;
					hdl = sess->hdl;
				} else {
					raise_ev = 1;
				}
			} else if (sess->hdl.name) {  /* MSRPUA_DLG_CONF */
				/* this should be a UAS session for which we have not received
				 * the ACK in time */
				if (pkg_str_dup(&sess_id, &sess->session_id) < 0) {
					LM_ERR("no more pkg memory\n");
					goto del_session;
				}

				cb_params.event = MSRP_UA_SESS_FAILED;
				cb_params.session_id = &sess_id;
				hdl = sess->hdl;
			}

			goto end;
		}

del_session:
		msrpua_delete_session(sess);
	}

end:
	if (raise_ev) {
		/* TODO: don't raise event/run callback under lock */
		if (raise_sess_end_event(&sess_id) < 0)
			LM_ERR("Failed to raise session end event on timeout\n");

		pkg_free(sess_id.s);
	} else if (cb_params.event) {
		hdl.notify_cb(&cb_params, hdl.param);

		pkg_free(sess_id.s);
	}

	return 0;
}

static void clean_msrpua_sessions(unsigned int ticks,void *param)
{
	hash_for_each_locked(msrpua_sessions, timer_clean_session, NULL);
}

void load_msrp_ua(struct msrp_ua_binds *binds)
{
	binds->init_uas = msrpua_init_uas;
	binds->init_uac = msrpua_init_uac;
	binds->end_session = msrpua_end_session;
	binds->send_message = msrpua_send_message;
}
