chan_sip.c

/*
 * Asterisk -- A telephony toolkit for Linux.
 *
 * Implementation of Session Initiation Protocol
 * 
 * Copyright (C) 1999, Mark Spencer
 *
 * Mark Spencer <markster@linux-support.net>
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License
 */

#include <stdio.h>
#include <ctype.h>
#include <pthread.h>
#include <string.h>
#include <asterisk/lock.h>
#include <asterisk/channel.h>
#include <asterisk/channel_pvt.h>
#include <asterisk/config.h>
#include <asterisk/logger.h>
#include <asterisk/module.h>
#include <asterisk/pbx.h>
#include <asterisk/options.h>
#include <asterisk/lock.h>
#include <asterisk/sched.h>
#include <asterisk/io.h>
#include <asterisk/rtp.h>
#include <asterisk/acl.h>
#include <asterisk/callerid.h>
#include <asterisk/cli.h>
#include <asterisk/md5.h>
#include <asterisk/app.h>
#include <asterisk/musiconhold.h>
#include <asterisk/dsp.h>
#include <asterisk/parking.h>
#include <asterisk/acl.h>
#include <asterisk/srv.h>
#include <asterisk/astdb.h>
#include <asterisk/causes.h>
#include <asterisk/utils.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <fcntl.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <pthread.h>
#include <signal.h>
#include <sys/signal.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>

#ifdef SIP_MYSQL_FRIENDS
#define MYSQL_FRIENDS
#include <mysql/mysql.h>
#endif

#ifndef DEFAULT_USERAGENT
#define DEFAULT_USERAGENT "Asterisk PBX"
#endif
 
#define VIDEO_CODEC_MASK        0x1fc0000 /* Video codecs from H.261 thru AST_FORMAT_MAX_VIDEO */
#ifndef IPTOS_MINCOST
#define IPTOS_MINCOST 0x02
#endif

/* #define VOCAL_DATA_HACK */

#define SIPDUMPER
#define DEFAULT_DEFAULT_EXPIRY  120
#define DEFAULT_MAX_EXPIRY      3600

/* guard limit must be larger than guard secs */
/* guard min must be < 1000, and should be >= 250 */
#define EXPIRY_GUARD_SECS	15	/* How long before expiry do we reregister */
#define EXPIRY_GUARD_LIMIT      30	/* Below here, we use EXPIRY_GUARD_PCT instead of EXPIRY_GUARD_SECS */
#define EXPIRY_GUARD_MIN	500	/* This is the minimum guard time applied. If GUARD_PCT turns out
					to be lower than this, it will use this time instead. This is in
					milliseconds. */
#define EXPIRY_GUARD_PCT        0.20	/* Percentage of expires timeout to use when below EXPIRY_GUARD_LIMIT */

#ifndef MAX
#define MAX(a,b) ((a) > (b) ? (a) : (b))
#endif

#define CALLERID_UNKNOWN	"Unknown"

/* --- Choices for DTMF support in SIP channel */
#define SIP_DTMF_RFC2833	(1 << 0)
#define SIP_DTMF_INBAND		(1 << 1)
#define SIP_DTMF_INFO		(1 << 2)

static int max_expiry = DEFAULT_MAX_EXPIRY;
static int default_expiry = DEFAULT_DEFAULT_EXPIRY;

#define DEFAULT_MAXMS		2000		/* Must be faster than 2 seconds by default */
#define DEFAULT_FREQ_OK		60 * 1000		/* How often to check for the host to be up */
#define DEFAULT_FREQ_NOTOK	10 * 1000		/* How often to check, if the host is down... */

#define DEFAULT_RETRANS		1000			/* How frequently to retransmit */
#define MAX_RETRANS		5			/* Try only 5 times for retransmissions */

/* MYSQL_FRIENDS: Check if peer exists in database and read some configuration
   from databse (not all options supported though) */
#ifdef MYSQL_FRIENDS
static ast_mutex_t mysqllock = AST_MUTEX_INITIALIZER;
static MYSQL *mysql;
static char mydbuser[80];
static char mydbpass[80];
static char mydbhost[80];
static char mydbname[80];
#endif

							/* SIP Debug		*/
#define DEBUG_READ	0				/* Recieved data	*/
#define DEBUG_SEND	1				/* Transmit data	*/

static char *desc = "Session Initiation Protocol (SIP)";
static char *type = "SIP";
static char *tdesc = "Session Initiation Protocol (SIP)";
static char *config = "sip.conf";

#define DEFAULT_SIP_PORT	5060	/* From RFC 2543 */
#define SIP_MAX_PACKET	1500		/* Also from RFC 2543, should sub headers tho */

#define ALLOWED_METHODS "INVITE, ACK, CANCEL, OPTIONS, BYE, REFER"

static char useragent[AST_MAX_EXTENSION] = DEFAULT_USERAGENT;

static char context[AST_MAX_EXTENSION] = "default";

static char language[MAX_LANGUAGE] = "";

static char callerid[AST_MAX_EXTENSION] = "asterisk";

static char fromdomain[AST_MAX_EXTENSION] = "";

static char notifymime[AST_MAX_EXTENSION] = "application/simple-message-summary";

static int srvlookup = 0;

static int pedanticsipchecking = 0;

static int autocreatepeer = 0;		

static int relaxdtmf = 0;

static int globalrtptimeout = 0;

static int globalrtpholdtimeout = 0;

static int usecnt =0;
static ast_mutex_t usecnt_lock = AST_MUTEX_INITIALIZER;

/* Protect the interface list (of sip_pvt's) */
static ast_mutex_t iflock = AST_MUTEX_INITIALIZER;

/* Protect the monitoring thread, so only one process can kill or start it, and not
   when it's doing something critical. */
static ast_mutex_t netlock = AST_MUTEX_INITIALIZER;

static ast_mutex_t monlock = AST_MUTEX_INITIALIZER;

/* This is the thread for the monitor which checks for input on the channels
   which are not currently in use.  */
static pthread_t monitor_thread = AST_PTHREADT_NULL;

static int restart_monitor(void);

/* Codecs that we support by default: */
static int capability = AST_FORMAT_ULAW | AST_FORMAT_ALAW | AST_FORMAT_GSM | AST_FORMAT_H263;
static int noncodeccapability = AST_RTP_DTMF;

static char ourhost[256];
static struct in_addr __ourip;
static int ourport;

static int sipdebug = 0;
static struct sockaddr_in debugaddr;

static int tos = 0;

static int videosupport = 0;

static int globaldtmfmode = SIP_DTMF_RFC2833;		/* DTMF mode default */
static int recordhistory = 0;

static char globalmusicclass[MAX_LANGUAGE] = "";	/* Global music on hold class */
static char global_realm[AST_MAX_EXTENSION] = "asterisk"; 	/* Default realm */

/* Expire slowly */
static int expiry = 900;

static struct sched_context *sched;
static struct io_context *io;
/* The private structures of the  sip channels are linked for
   selecting outgoing channels */
   
#define SIP_MAX_HEADERS		64
#define SIP_MAX_LINES 		64

#define DEC_IN_USE	0
#define INC_IN_USE	1
#define DEC_OUT_USE	2
#define INC_OUT_USE	3

static struct sip_codec_pref {
	int codec;
	struct sip_codec_pref *next;
} *prefs;

/* sip_request: The data grabbed from the UDP socket */
struct sip_request {
  char *rlPart1; /* SIP Method Name or "SIP/2.0" protocol version */
  char *rlPart2; /* The Request URI or Response Status */
	int len;
	int headers;					/* SIP Headers */
	char *header[SIP_MAX_HEADERS];
	int lines;						/* SDP Content */
	char *line[SIP_MAX_LINES];
	char data[SIP_MAX_PACKET];
};

struct sip_pkt;

struct sip_route {
	struct sip_route *next;
	char hop[0];
};

struct sip_history {
	char event[80];
	struct sip_history *next;
};

/* sip_pvt: PVT structures are used for each SIP conversation, ie. a call  */
static struct sip_pvt {
	ast_mutex_t lock;			/* Channel private lock */
	char callid[80];			/* Global CallID */
	char randdata[80];			/* Random data */
	unsigned int ocseq;			/* Current outgoing seqno */
	unsigned int icseq;			/* Current incoming seqno */
	unsigned int callgroup;			/* Call group */
	unsigned int pickupgroup;		/* Pickup group */
	int lastinvite;				/* Last Cseq of invite */
	int alreadygone;			/* Whether or not we've already been destroyed by or peer */
	int needdestroy;			/* if we need to be destroyed */
	int capability;				/* Special capability (codec) */
	int jointcapability;			/* Supported capability at both ends (codecs ) */
	int prefcodec;				/* Preferred codec (outbound only) */
	int noncodeccapability;
	int outgoing;				/* Outgoing or incoming call? */
	int authtries;				/* Times we've tried to authenticate */
	int insecure;				/* Don't check source port/ip */
	int expiry;				/* How long we take to expire */
	int branch;				/* One random number */
	int canreinvite;			/* Do we support reinvite */
	int ringing;				/* Have sent 180 ringing */
	int progress;				/* Have sent 183 message progress */
	int tag;				/* Another random number */
	int nat;				/* Whether to try to support NAT */
	int sessionid;				/* SDP Session ID */
	int sessionversion;			/* SDP Session Version */
	struct sockaddr_in sa;			/* Our peer */
	struct sockaddr_in redirip;		/* Where our RTP should be going if not to us */
	struct sockaddr_in vredirip;		/* Where our Video RTP should be going if not to us */
	int redircodecs;				/* Redirect codecs */
	struct sockaddr_in recv;		/* Received as */
	struct in_addr ourip;			/* Our IP */
	struct ast_channel *owner;		/* Who owns us */
	char exten[AST_MAX_EXTENSION];		/* Extension where to start */
	char refer_to[AST_MAX_EXTENSION];	/* Place to store REFER-TO extension */
	char referred_by[AST_MAX_EXTENSION];	/* Place to store REFERRED-BY extension */
	char refer_contact[AST_MAX_EXTENSION];	/* Place to store Contact info from a REFER extension */
	struct sip_pvt *refer_call;		/* Call we are referring */
	struct sip_route *route;		/* Head of linked list of routing steps (fm Record-Route) */
	int route_persistant;			/* Is this the "real" route? */
	char remote_party_id[256];
	char from[256];				/* The From: header */
	char useragent[256];			/* User agent in SIP request */
	char context[AST_MAX_EXTENSION];	/* Context for this call */
	char fromdomain[AST_MAX_EXTENSION];	/* Domain to show in the from field */
	char fromuser[AST_MAX_EXTENSION];	/* Domain to show in the user field */
	char tohost[AST_MAX_EXTENSION];		/* Host we should put in the "to" field */
	char language[MAX_LANGUAGE];		/* Default language for this call */
	char musicclass[MAX_LANGUAGE];          /* Music on Hold class */
	char rdnis[256];			/* Referring DNIS */
	char theirtag[256];			/* Their tag */
	char username[256];
	char peername[256];
	char authname[256];			/* Who we use for authentication */
	char uri[256];				/* Original requested URI */
	char peersecret[256];
	char peermd5secret[256];
	char callerid[256];			/* Caller*ID */
	int restrictcid;			/* hide presentation from remote user */
	char via[256];
	char accountcode[20];			/* Account code */
	char our_contact[256];			/* Our contact header */
	char realm[256];			/* Authorization realm */
	char nonce[256];			/* Authorization nonce */
	char opaque[256];			/* Opaque nonsense */
	char qop[80];				/* Quality of Protection, since SIP wasn't complicated enough yet. */
	char domain[256];			/* Authorization nonce */
	char lastmsg[256];			/* Last Message sent/received */
	int amaflags;				/* AMA Flags */
	int pendinginvite;			/* Any pending invite */
	int needreinvite;			/* Do we need to send another reinvite? */
	int pendingbye;				/* Need to send bye after we ack? */
	int gotrefer;				/* Got a refer? */
	struct sip_request initreq;		/* Initial request */
	
	int maxtime;				/* Max time for first response */
	int initid;				/* Auto-congest ID if appropriate */
	int autokillid;				/* Auto-kill ID */
	time_t lastrtprx;			/* Last RTP received */
	int rtptimeout;				/* RTP timeout time */
	int rtpholdtimeout;			/* RTP timeout when on hold */

	int subscribed;
    	int stateid;
	int dialogver;
	
        int dtmfmode;
        struct ast_dsp *vad;
	
	struct sip_peer *peerpoke;		/* If this calls is to poke a peer, which one */
	struct sip_registry *registry;		/* If this is a REGISTER call, to which registry */
	struct ast_rtp *rtp;			/* RTP Session */
	struct ast_rtp *vrtp;			/* Video RTP session */
	struct sip_pkt *packets;		/* Packets scheduled for re-transmission */
	struct sip_history *history;	/* History of this SIP dialog */
	struct sip_pvt *next;			/* Next call in chain */
} *iflist = NULL;

#define FLAG_RESPONSE (1 << 0)
#define FLAG_FATAL (1 << 1)

/* sip packet - read in sipsock_read, transmitted in send_request */
struct sip_pkt {
	struct sip_pkt *next;				/* Next packet */
	int retrans;						/* Retransmission number */
	int seqno;							/* Sequence number */
	int flags;							/* non-zero if this is a response packet (e.g. 200 OK) */
	struct sip_pvt *owner;				/* Owner call */
	int retransid;						/* Retransmission ID */
	int packetlen;						/* Length of packet */
	char data[0];
};	

/* Structure for SIP user data. User's place calls to us */
struct sip_user {
	/* Users who can access various contexts */
	char name[80];
	char secret[80];
        char md5secret[80];
	char context[80];
	char callerid[80];
	char accountcode[20];
	char language[MAX_LANGUAGE];
	char musicclass[MAX_LANGUAGE];  /* Music on Hold class */
	char useragent[256];		/* User agent in SIP request */
	unsigned int callgroup;
	unsigned int pickupgroup;
	int nat;
	int hascallerid;
	int amaflags;
	int insecure;
	int canreinvite;
	int capability;
	int dtmfmode;
	int inUse;
	int incominglimit;
	int outUse;
	int outgoinglimit;
	int restrictcid;
	struct ast_ha *ha;
	struct sip_user *next;
};

/* Structure for SIP peer data, we place calls to peers if registred  or fixed IP address (host) */
struct sip_peer {
	char name[80];
	char secret[80];
	char md5secret[80];
	char context[80];		/* JK02: peers need context too to allow parking etc */
	char username[80];
	char tohost[80];
	char fromuser[80];
	char fromdomain[80];
	char mailbox[AST_MAX_EXTENSION];
	char language[MAX_LANGUAGE];
	char musicclass[MAX_LANGUAGE];  /* Music on Hold class */
	char useragent[256];		/* User agent in SIP request */
	int lastmsgssent;
	time_t	lastmsgcheck;
	int dynamic;
	int expire;
	int expiry;
	int capability;
	int rtptimeout;
	int rtpholdtimeout;
	int insecure;
	int nat;
	int canreinvite;
	unsigned int callgroup;
	unsigned int pickupgroup;
        int dtmfmode;
	struct sockaddr_in addr;
	struct in_addr mask;

	/* Qualification */
	struct sip_pvt *call;		/* Call pointer */
	int pokeexpire;				/* When to expire poke */
	int lastms;					/* How long last response took (in ms), or -1 for no response */
	int maxms;					/* Max ms we will accept for the host to be up, 0 to not monitor */
	struct timeval ps;			/* Ping send time */
	
	struct sockaddr_in defaddr;
	struct ast_ha *ha;
	int delme;
	int selfdestruct;
	int lastmsg;
	int temponly;
	struct sip_peer *next;
};

static ast_mutex_t sip_reload_lock = AST_MUTEX_INITIALIZER;
static int sip_reloading = 0;

#define REG_STATE_UNREGISTERED 0
#define REG_STATE_REGSENT	   1
#define REG_STATE_AUTHSENT 	   2
#define REG_STATE_REGISTERED   3
#define REG_STATE_REJECTED	   4
#define REG_STATE_TIMEOUT	   5
#define REG_STATE_NOAUTH	   6

/* sip_registry: Registrations with other SIP proxies */
struct sip_registry {
	struct sockaddr_in addr;	/* Who we connect to for registration purposes */
	char username[80];		/* Who we are registering as */
	char authuser[80];		/* Who we *authenticate* as */
	char hostname[80];
	char secret[80];		/* Password or key name in []'s */	
	char md5secret[80];
	char contact[80];		/* Contact extension */
	char random[80];
	int expire;			/* Sched ID of expiration */
	int timeout; 			/* sched id of sip_reg_timeout */
	int refresh;			/* How often to refresh */
	struct sip_pvt *call;		/* create a sip_pvt structure for each outbound "registration call" in progress */
	int regstate;
	int callid_valid;		/* 0 means we haven't chosen callid for this registry yet. */
	char callid[80];		/* Global CallID for this registry */
	unsigned int ocseq;		/* Sequence number we got to for REGISTERs for this registry */
	struct sockaddr_in us;		/* Who the server thinks we are */
	struct sip_registry *next;
};

/*--- The user list: Users and friends ---*/
static struct ast_user_list {
	struct sip_user *users;
	ast_mutex_t lock;
} userl = { NULL, AST_MUTEX_INITIALIZER };

/*--- The peer list: Peers and Friends ---*/
static struct ast_peer_list {
	struct sip_peer *peers;
	ast_mutex_t lock;
} peerl = { NULL, AST_MUTEX_INITIALIZER };

/*--- The register list: Other SIP proxys we register with and call ---*/
static struct ast_register_list {
	struct sip_registry *registrations;
	ast_mutex_t lock;
	int recheck;
} regl = { NULL, AST_MUTEX_INITIALIZER };


#define REINVITE_INVITE		1
#define REINVITE_UPDATE		2

static int __sip_do_register(struct sip_registry *r);

static int sipsock  = -1;
static int globalnat = 0;
static int globalcanreinvite = REINVITE_INVITE;


static struct sockaddr_in bindaddr;
static struct sockaddr_in externip;
static struct ast_ha *localaddr;

static struct ast_frame  *sip_read(struct ast_channel *ast);
static int transmit_response(struct sip_pvt *p, char *msg, struct sip_request *req);
static int transmit_response_with_sdp(struct sip_pvt *p, char *msg, struct sip_request *req, int retrans);
static int transmit_response_with_auth(struct sip_pvt *p, char *msg, struct sip_request *req, char *rand, int reliable);
static int transmit_request(struct sip_pvt *p, char *msg, int inc, int reliable, int newbranch);
static int transmit_request_with_auth(struct sip_pvt *p, char *msg, int inc, int reliable, int newbranch);
static int transmit_invite(struct sip_pvt *p, char *msg, int sendsdp, char *auth, char *authheader, char *vxml_url,char *distinctive_ring, int init);
static int transmit_reinvite_with_sdp(struct sip_pvt *p);
static int transmit_info_with_digit(struct sip_pvt *p, char digit);
static int transmit_message_with_text(struct sip_pvt *p, char *text);
static int transmit_refer(struct sip_pvt *p, char *dest);
static struct sip_peer *temp_peer(char *name);
static int do_proxy_auth(struct sip_pvt *p, struct sip_request *req, char *header, char *respheader, char *msg, int init);
static void free_old_route(struct sip_route *route);
static int build_reply_digest(struct sip_pvt *p, char *orig_header, char *digest, int digest_len);
static int update_user_counter(struct sip_pvt *fup, int event);
static void prune_peers(void);
static int sip_do_reload(void);
static int sip_debug_test_addr(struct sockaddr_in *addr);
static int sip_debug_test_pvt(struct sip_pvt *p);

/*--- __sip_xmit: Transmit SIP message ---*/
static int __sip_xmit(struct sip_pvt *p, char *data, int len)
{
	int res;
	if (p->nat)
	    res=sendto(sipsock, data, len, 0, (struct sockaddr *)&p->recv, sizeof(struct sockaddr_in));
	else
	    res=sendto(sipsock, data, len, 0, (struct sockaddr *)&p->sa, sizeof(struct sockaddr_in));
	if (res != len) {
		ast_log(LOG_WARNING, "sip_xmit of %p (len %d) to %s returned %d: %s\n", data, len, inet_ntoa(p->sa.sin_addr), res, strerror(errno));
	}
	return res;
}

static void sip_destroy(struct sip_pvt *p);

/*--- ast_sip_ouraddrfor: NAT fix - decide which IP address to use for ASterisk server? ---*/
/* Only used for outbound registrations */
static int ast_sip_ouraddrfor(struct in_addr *them, struct in_addr *us)
{
	/*
	 * Using the localaddr structure built up with localnet statements
	 * apply it to their address to see if we need to substitute our
	 * externip or can get away with our internal bindaddr
	 */
	struct sockaddr_in theirs;
	theirs.sin_addr = *them;
	if (localaddr && externip.sin_addr.s_addr &&
	   ast_apply_ha(localaddr, &theirs)) {
		char t[256];
		memcpy(us, &externip.sin_addr, sizeof(struct in_addr));
		strcpy(t, inet_ntoa(*(struct in_addr *)&them->s_addr));
		ast_log(LOG_DEBUG, "Target address %s is not local, substituting externip\n", t);
	}
	else if (bindaddr.sin_addr.s_addr)
		memcpy(us, &bindaddr.sin_addr, sizeof(struct in_addr));
	else
		return ast_ouraddrfor(them, us);
	return 0;
}

static int append_history(struct sip_pvt *p, char *event, char *data)
{
	struct sip_history *hist, *prev;
	char *c;
	if (!recordhistory)
		return 0;
	hist = malloc(sizeof(struct sip_history));
	if (hist) {
		memset(hist, 0, sizeof(struct sip_history));
		snprintf(hist->event, sizeof(hist->event), "%-15s %s", event, data);
		/* Trim up nicely */
		c = hist->event;
		while(*c) {
			if ((*c == '\r') || (*c == '\n')) {
				*c = '\0';
				break;
			}
			c++;
		}
		/* Enqueue into history */
		prev = p->history;
		if (prev) {
			while(prev->next)
				prev = prev->next;
			prev->next = hist;
		} else {
			p->history = hist;
		}
	}
	return 0;
}

/*--- retrans_pkt: Retransmit SIP message if no answer ---*/
static int retrans_pkt(void *data)
{
	struct sip_pkt *pkt=data, *prev, *cur;
	int res = 0;
	ast_mutex_lock(&pkt->owner->lock);
	if (pkt->retrans < MAX_RETRANS) {
		pkt->retrans++;
		if (sip_debug_test_pvt(pkt->owner)) {
			if (pkt->owner->nat)
				ast_verbose("Retransmitting #%d (NAT):\n%s\n to %s:%d\n", pkt->retrans, pkt->data, inet_ntoa(pkt->owner->recv.sin_addr), ntohs(pkt->owner->recv.sin_port));
			else
				ast_verbose("Retransmitting #%d (no NAT):\n%s\n to %s:%d\n", pkt->retrans, pkt->data, inet_ntoa(pkt->owner->sa.sin_addr), ntohs(pkt->owner->sa.sin_port));
		}
		append_history(pkt->owner, "ReTx", pkt->data);
		__sip_xmit(pkt->owner, pkt->data, pkt->packetlen);
		res = 1;
	} else {
		ast_log(LOG_WARNING, "Maximum retries exceeded on call %s for seqno %d (%s %s)\n", pkt->owner->callid, pkt->seqno, (pkt->flags & FLAG_FATAL) ? "Critical" : "Non-critical", (pkt->flags & FLAG_RESPONSE) ? "Response" : "Request");
		append_history(pkt->owner, "MaxRetries", pkt->flags & FLAG_FATAL ? "(Critical)" : "(Non-critical)");
		pkt->retransid = -1;
		if (pkt->flags & FLAG_FATAL) {
			while(pkt->owner->owner && ast_mutex_trylock(&pkt->owner->owner->lock)) {
				ast_mutex_unlock(&pkt->owner->lock);
				usleep(1);
				ast_mutex_lock(&pkt->owner->lock);
			}
			if (pkt->owner->owner) {
				ast_queue_hangup(pkt->owner->owner);
				ast_mutex_unlock(&pkt->owner->owner->lock);
			} else {
				/* If no owner, destroy now */
				pkt->owner->needdestroy = 1;
			}
		}
		/* In any case, go ahead and remove the packet */
		prev = NULL;
		cur = pkt->owner->packets;
		while(cur) {
			if (cur == pkt)
				break;
			prev = cur;
			cur = cur->next;
		}
		if (cur) {
			if (prev)
				prev->next = cur->next;
			else
				pkt->owner->packets = cur->next;
			ast_mutex_unlock(&pkt->owner->lock);
			free(cur);
			pkt = NULL;
		} else
			ast_log(LOG_WARNING, "Weird, couldn't find packet owner!\n");
	}
	if (pkt)
		ast_mutex_unlock(&pkt->owner->lock);
	return res;
}

/*--- __sip_reliable_xmit: transmit packet with retransmits ---*/
static int __sip_reliable_xmit(struct sip_pvt *p, int seqno, int resp, char *data, int len, int fatal)
{
	struct sip_pkt *pkt;
	pkt = malloc(sizeof(struct sip_pkt) + len);
	if (!pkt)
		return -1;
	memset(pkt, 0, sizeof(struct sip_pkt));
	memcpy(pkt->data, data, len);
	pkt->packetlen = len;
	pkt->next = p->packets;
	pkt->owner = p;
	pkt->seqno = seqno;
	pkt->flags = resp;
	if (fatal)
		pkt->flags |= FLAG_FATAL;
	/* Schedule retransmission */
	pkt->retransid = ast_sched_add(sched, DEFAULT_RETRANS, retrans_pkt, pkt);
	pkt->next = p->packets;
	p->packets = pkt;
	__sip_xmit(pkt->owner, pkt->data, pkt->packetlen);
	if (!strncasecmp(pkt->data, "INVITE", 6)) {
		/* Note this is a pending invite */
		p->pendinginvite = seqno;
	}
	return 0;
}

/*--- __sip_autodestruct: Kill a call (called by scheduler) ---*/
static int __sip_autodestruct(void *data)
{
	struct sip_pvt *p = data;
	p->autokillid = -1;
	ast_log(LOG_DEBUG, "Auto destroying call '%s'\n", p->callid);
	append_history(p, "AutoDestroy", "");
	if (p->owner) {
		ast_log(LOG_WARNING, "Autodestruct on call '%s' with owner in place\n", p->callid);
		ast_queue_hangup(p->owner);
	} else {
		sip_destroy(p);
	}
	return 0;
}

/*--- sip_scheddestroy: Schedule destruction of SIP call ---*/
static int sip_scheddestroy(struct sip_pvt *p, int ms)
{
	char tmp[80];
	if (sip_debug_test_pvt(p))
		ast_verbose("Scheduling destruction of call '%s' in %d ms\n", p->callid, ms);
	if (recordhistory) {
		snprintf(tmp, sizeof(tmp), "%d ms", ms);
		append_history(p, "SchedDestroy", tmp);
	}
	if (p->autokillid > -1)
		ast_sched_del(sched, p->autokillid);
	p->autokillid = ast_sched_add(sched, ms, __sip_autodestruct, p);
	return 0;
}

/*--- sip_cancel_destroy: Cancel destruction of SIP call ---*/
static int sip_cancel_destroy(struct sip_pvt *p)
{
	if (p->autokillid > -1)
		ast_sched_del(sched, p->autokillid);
	append_history(p, "CancelDestroy", "");
	p->autokillid = -1;
	return 0;
}

/*--- __sip_ack: Acknowledges receipt of a packet and stops retransmission ---*/
static int __sip_ack(struct sip_pvt *p, int seqno, int resp)
{
	struct sip_pkt *cur, *prev = NULL;
	int res = -1;
	int resetinvite = 0;
	cur = p->packets;
	while(cur) {
		if ((cur->seqno == seqno) && ((cur->flags & FLAG_RESPONSE) == resp)) {
			if (!resp && (seqno == p->pendinginvite)) {
				ast_log(LOG_DEBUG, "Acked pending invite %d\n", p->pendinginvite);
				p->pendinginvite = 0;
				resetinvite = 1;
			}
			/* this is our baby */
			if (prev)
				prev->next = cur->next;
			else
				p->packets = cur->next;
			if (cur->retransid > -1)
				ast_sched_del(sched, cur->retransid);
			free(cur);
			res = 0;
			break;
		}
		prev = cur;
		cur = cur->next;
	}
	ast_log(LOG_DEBUG, "Stopping retransmission on '%s' of %s %d: %s\n", p->callid, resp ? "Response" : "Request", seqno, res ? "Not Found" : "Found");
	return res;
}

/*--- __sip_semi_ack: Acks receipt of packet, keep it around (used for provisional responses) ---*/
static int __sip_semi_ack(struct sip_pvt *p, int seqno, int resp)
{
	struct sip_pkt *cur;
	int res = -1;
	cur = p->packets;
	while(cur) {
		if ((cur->seqno == seqno) && ((cur->flags & FLAG_RESPONSE) == resp)) {
			/* this is our baby */
			if (cur->retransid > -1)
				ast_sched_del(sched, cur->retransid);
			cur->retransid = -1;
			res = 0;
			break;
		}
		cur = cur->next;
	}
	ast_log(LOG_DEBUG, "(Provisional) Stopping retransmission (but retaining packet) on '%s' %s %d: %s\n", p->callid, resp ? "Response" : "Request", seqno, res ? "Not Found" : "Found");
	return res;
}

/*--- send_response: Transmit response on SIP request---*/
static int send_response(struct sip_pvt *p, struct sip_request *req, int reliable, int seqno)
{
	int res;
	if (sip_debug_test_pvt(p)) {
		if (p->nat)
			ast_verbose("%sTransmitting (NAT):\n%s\n to %s:%d\n", reliable ? "Reliably " : "", req->data, inet_ntoa(p->recv.sin_addr), ntohs(p->recv.sin_port));
		else
			ast_verbose("%sTransmitting (no NAT):\n%s\n to %s:%d\n", reliable ? "Reliably " : "", req->data, inet_ntoa(p->sa.sin_addr), ntohs(p->sa.sin_port));
	}
	if (reliable) {
		append_history(p, "TxRespRel", req->data);
		res = __sip_reliable_xmit(p, seqno, 1, req->data, req->len, (reliable > 1));
	} else {
		append_history(p, "TxResp", req->data);
		res = __sip_xmit(p, req->data, req->len);
	}
	if (res > 0)
		res = 0;
	return res;
}

/*--- send_request: Send SIP Request to the other part of the dialogue ---*/
static int send_request(struct sip_pvt *p, struct sip_request *req, int reliable, int seqno)
{
	int res;
	if (sip_debug_test_pvt(p)) {
		if (p->nat)
			ast_verbose("%sTransmitting:\n%s (NAT) to %s:%d\n", reliable ? "Reliably " : "", req->data, inet_ntoa(p->recv.sin_addr), ntohs(p->recv.sin_port));
		else
			ast_verbose("%sTransmitting:\n%s (no NAT) to %s:%d\n", reliable ? "Reliably " : "", req->data, inet_ntoa(p->sa.sin_addr), ntohs(p->sa.sin_port));
	}
	if (reliable) {
		append_history(p, "TxReqRel", req->data);
		res = __sip_reliable_xmit(p, seqno, 0, req->data, req->len, (reliable > 1));
	} else {
		append_history(p, "TxReq", req->data);
		res = __sip_xmit(p, req->data, req->len);
	}
	return res;
}

/*--- ditch_braces: Pick out text in braces from character string  ---*/
static char *ditch_braces(char *tmp)
{
	char *c = tmp;
	char *n;
	if ((n = strchr(tmp, '<')) ) {
		c = n + 1;
		while(*c && *c != '>') c++;
		if (*c != '>') {
			ast_log(LOG_WARNING, "No closing brace in '%s'\n", tmp);
		} else {
			*c = '\0';
		}
		return n+1;
	}
	return c;
}

/*--- sip_sendtext: Send SIP MESSAGE text within a call ---*/
/*      Called from PBX core text message functions */
static int sip_sendtext(struct ast_channel *ast, char *text)
{
	struct sip_pvt *p = ast->pvt->pvt;
	if (sip_debug_test_pvt(p))
		ast_verbose("Sending text %s on %s\n", text, ast->name);
	if (!p)
		return -1;
	if (!text || ast_strlen_zero(text))
		return 0;
	if (sip_debug_test_pvt(p))
		ast_verbose("Really sending text %s on %s\n", text, ast->name);
	transmit_message_with_text(p, text);
	return 0;	
}

#ifdef MYSQL_FRIENDS

/*--- mysql_update_peer: Update peer from database ---*/
/* This function adds registration state to database */
static void mysql_update_peer(char *peer, struct sockaddr_in *sin, char *username, int expiry)
{
	if (mysql && (strlen(peer) < 128)) {
		char query[512];
		char *name;
		char *uname;
		time_t nowtime;
		name = alloca(strlen(peer) * 2 + 1);
		uname = alloca(strlen(username) * 2 + 1);
		time(&nowtime);
		mysql_real_escape_string(mysql, name, peer, strlen(peer));
		mysql_real_escape_string(mysql, uname, username, strlen(username));
		snprintf(query, sizeof(query), "UPDATE sipfriends SET ipaddr=\"%s\", port=\"%d\", regseconds=\"%ld\", username=\"%s\" WHERE name=\"%s\"", 
			inet_ntoa(sin->sin_addr), ntohs(sin->sin_port), nowtime + expiry, uname, name);
		ast_mutex_lock(&mysqllock);
		if (mysql_real_query(mysql, query, strlen(query))) 
			ast_log(LOG_WARNING, "Unable to update database\n");
			
		ast_mutex_unlock(&mysqllock);
	}
}

/*--- mysql_peer: Get peer from database ---*/
static struct sip_peer *mysql_peer(char *peer, struct sockaddr_in *sin)
{
	struct sip_peer *p;
	int success = 0;
	
	p = malloc(sizeof(struct sip_peer));
	memset(p, 0, sizeof(struct sip_peer));
	if (mysql && (!peer || (strlen(peer) < 128))) {
		char query[512];
		char *name = NULL;
		int numfields, x;
		int port;
		time_t regseconds, nowtime;
		MYSQL_RES *result;
		MYSQL_FIELD *fields;
		MYSQL_ROW rowval;
		if (peer) {
			name = alloca(strlen(peer) * 2 + 1);
			mysql_real_escape_string(mysql, name, peer, strlen(peer));
		}
		if (sin)
			snprintf(query, sizeof(query), "SELECT name, secret, context, username, ipaddr, port, regseconds FROM sipfriends WHERE ipaddr=\"%s\" AND port=\"%d\"", inet_ntoa(sin->sin_addr), ntohs(sin->sin_port));
		else
			snprintf(query, sizeof(query), "SELECT name, secret, context, username, ipaddr, port, regseconds FROM sipfriends WHERE name=\"%s\"", name);
		ast_mutex_lock(&mysqllock);
		mysql_query(mysql, query);
		if ((result = mysql_store_result(mysql))) {
			if ((rowval = mysql_fetch_row(result))) {
				numfields = mysql_num_fields(result);
				fields = mysql_fetch_fields(result);
				success = 1;
				p->addr.sin_family = AF_INET;
				for (x=0;x<numfields;x++) {
					if (rowval[x]) {
						if (!strcasecmp(fields[x].name, "secret")) {
							strncpy(p->secret, rowval[x], sizeof(p->secret));
						} else if (!strcasecmp(fields[x].name, "name")) {
							strncpy(p->name, rowval[x], sizeof(p->name) - 1);
						} else if (!strcasecmp(fields[x].name, "context")) {
							strncpy(p->context, rowval[x], sizeof(p->context) - 1);
						} else if (!strcasecmp(fields[x].name, "username")) {
							strncpy(p->username, rowval[x], sizeof(p->username) - 1);
						} else if (!strcasecmp(fields[x].name, "ipaddr")) {
							inet_aton(rowval[x], &p->addr.sin_addr);
						} else if (!strcasecmp(fields[x].name, "port")) {
							if (sscanf(rowval[x], "%i", &port) != 1)
								port = 0;
							p->addr.sin_port = htons(port);
						} else if (!strcasecmp(fields[x].name, "regseconds")) {
							if (sscanf(rowval[x], "%li", &regseconds) != 1)
								regseconds = 0;
						}
					}
				}
				time(&nowtime);
				if (nowtime > regseconds) 
					memset(&p->addr, 0, sizeof(p->addr));
			}
			mysql_free_result(result);
			result = NULL;
		}
		ast_mutex_unlock(&mysqllock);
	}
	if (!success) {
		free(p);
		p = NULL;
	} else {
		p->dynamic = 1;
		p->capability = capability;
		p->nat = globalnat;
		p->dtmfmode = globaldtmfmode;
		p->insecure = 1;
		p->expire = -1;
		p->temponly = 1;
		
	}
	return p;
}
#endif /* MYSQL_FRIENDS */

/*--- update_peer: Update peer data in database (if used) ---*/
static void update_peer(struct sip_peer *p, int expiry)
{
#ifdef MYSQL_FRIENDS
	if (p->temponly)
		mysql_update_peer(p->name, &p->addr, p->username, expiry);
#endif
	return;
}

/*--- find_peer: Locate peer by name or ip address */
static struct sip_peer *find_peer(char *peer, struct sockaddr_in *sin)
{
	struct sip_peer *p = NULL;

	p = peerl.peers;
	if (peer) {
		/* Find by peer name */
		while(p) {
			if (!strcasecmp(p->name, peer)) {
				break;
			}
			p = p->next;
		}	
	}
	else {
		/* Find by sin */
		while(p) {
			if (!inaddrcmp(&p->addr, sin) || 
					(p->insecure &&
					(p->addr.sin_addr.s_addr == sin->sin_addr.s_addr))) {
				break;
			}
			p = p->next;
		}
	}

#ifdef MYSQL_FRIENDS
	if (!p) {
		p = mysql_peer(peer, sin);