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clean up pedantic mode tag handling (issue #5125)

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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@6767 65c4cc65-6c06-0410-ace0-fbb531ad65f3
1.2-netsec
Kevin P. Fleming 20 years ago
parent 7734cca1c2
commit c05c0c7ce6
1 changed files with 97 additions and 38 deletions
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135
channels/chan_sip.c
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@ -450,6 +450,7 @@ struct sip_request {
char *line[SIP_MAX_LINES];
char data[SIP_MAX_PACKET];
int debug; /* Debug flag for this packet */
unsigned int flags; /* SIP_PKT Flags for this packet */
};
struct sip_pkt;
@ -565,6 +566,10 @@ struct sip_auth {
#define SIP_PAGE2_RTAUTOCLEAR (1 << 2)
#define SIP_PAGE2_RTIGNOREREGEXPIRE (1 << 3)
/* SIP packet flags */
#define SIP_PKT_DEBUG (1 << 0) /* Debug this packet */
#define SIP_PKT_WITH_TOTAG (1 << 1) /* This packet has a to-tag */
static int global_rtautoclear = 120;
/* sip_pvt: PVT structures are used for each SIP conversation, ie. a call */
@ -910,6 +915,7 @@ static int determine_firstline_parts(struct sip_request *req);
static void sip_dump_history(struct sip_pvt *dialog); /* Dump history to LOG_DEBUG at end of dialog, before destroying data */
static const struct cfsubscription_types *find_subscription_type(enum subscriptiontype subtype);
static int transmit_state_notify(struct sip_pvt *p, int state, int full, int substate);
static char *gettag(struct sip_request *req, char *header, char *tagbuf, int tagbufsize);
/* Definition of this channel for channel registration */
static const struct ast_channel_tech sip_tech = {
@ -3072,13 +3078,14 @@ static struct sip_pvt *sip_alloc(char *callid, struct sockaddr_in *sin, int useg
}
/*--- find_call: Connect incoming SIP message to current dialog or create new dialog structure */
/* Called by handle_request ,sipsock_read */
/* Called by handle_request, sipsock_read */
static struct sip_pvt *find_call(struct sip_request *req, struct sockaddr_in *sin, const int intended_method)
{
struct sip_pvt *p;
char *callid;
char tmp[256];
char *tag = "", *c;
char *tag = "";
char totag[128];
char fromtag[128];
callid = get_header(req, "Call-ID");
@ -3086,32 +3093,51 @@ static struct sip_pvt *find_call(struct sip_request *req, struct sockaddr_in *si
/* In principle Call-ID's uniquely identify a call, but with a forking SIP proxy
we need more to identify a branch - so we have to check branch, from
and to tags to identify a call leg.
For Asterisk to behave correctly, you need to turn on pedanticsipchecking
For Asterisk to behave correctly, you need to turn on pedanticsipchecking
in sip.conf
*/
if (gettag(req, "To", totag, sizeof(totag)))
ast_set_flag(req, SIP_PKT_WITH_TOTAG); /* Used in handle_request/response */
gettag(req, "From", fromtag, sizeof(fromtag));
if (req->method == SIP_RESPONSE)
ast_copy_string(tmp, get_header(req, "To"), sizeof(tmp));
tag = totag;
else
ast_copy_string(tmp, get_header(req, "From"), sizeof(tmp));
tag = strcasestr(tmp, "tag=");
if (tag) {
tag += 4;
c = strchr(tag, ';');
if (c)
*c = '\0';
}
tag = fromtag;
if (option_debug > 4 )
ast_log(LOG_DEBUG, "= Looking for Call ID: %s (Checking %s) --From tag %s --To-tag %s \n", callid, req->method==SIP_RESPONSE ? "To" : "From", fromtag, totag);
}
ast_mutex_lock(&iflock);
p = iflist;
while(p) {
while(p) { /* In pedantic, we do not want packets with bad syntax to be connected to a PVT */
int found = 0;
if (req->method == SIP_REGISTER)
found = (!strcmp(p->callid, callid));
else
found = (!strcmp(p->callid, callid) &&
(!pedanticsipchecking || !tag || ast_strlen_zero(p->theirtag) || !strcmp(p->theirtag, tag))) ;
if (option_debug > 4)
ast_log(LOG_DEBUG, "= %s Their Call ID: %s Their Tag %s Our tag: %s\n", found ? "Found" : "No match", p->callid, p->theirtag, p->tag);
/* If we get a new request within an existing to-tag - check the to tag as well */
if (pedanticsipchecking && found && req->method != SIP_RESPONSE) { /* SIP Request */
if (p->tag[0] == '\0' && totag[0]) {
/* We have no to tag, but they have. Wrong dialog */
found = 0;
} else if (totag[0]) { /* Both have tags, compare them */
if (strcmp(totag, p->tag)) {
found = 0; /* This is not our packet */
}
}
if (!found && option_debug > 4)
ast_log(LOG_DEBUG, "= Being pedantic: This is not our match on request: Call ID: %s Ourtag <null> Totag %s Method %s\n", p->callid, totag, sip_methods[req->method].text);
}
if (found) {
/* Found the call */
ast_mutex_lock(&p->lock);
@ -9659,7 +9685,6 @@ static int handle_response_peerpoke(struct sip_pvt *p, int resp, char *rest, str
/*--- handle_response: Handle SIP response in dialogue ---*/
static void handle_response(struct sip_pvt *p, int resp, char *rest, struct sip_request *req, int ignore, int seqno)
{
char *to;
char *msg, *c;
struct ast_channel *owner;
char iabuf[INET_ADDRSTRLEN];
@ -9686,15 +9711,7 @@ static void handle_response(struct sip_pvt *p, int resp, char *rest, struct sip_
/* Get their tag if we haven't already */
if (ast_strlen_zero(p->theirtag) || (resp >= 200)) {
to = get_header(req, "To");
to = strcasestr(to, "tag=");
if (to) {
to += 4;
ast_copy_string(p->theirtag, to, sizeof(p->theirtag));
to = strchr(p->theirtag, ';');
if (to)
*to = '\0';
}
gettag(req, "To", p->theirtag, sizeof(p->theirtag));
}
if (p->peerpoke) {
/* We don't really care what the response is, just that it replied back.
@ -9877,6 +9894,12 @@ static void handle_response(struct sip_pvt *p, int resp, char *rest, struct sip_
get handled here. As well as out-of-call message responses */
if (req->debug)
ast_verbose("SIP Response message for INCOMING dialog %s arrived\n", msg);
if (resp == 200) {
/* Tags in early session is replaced by the tag in 200 OK, which is
the final reply to our INVITE */
gettag(req, "To", p->theirtag, sizeof(p->theirtag));
}
switch(resp) {
case 200:
if (sipmethod == SIP_INVITE) {
@ -10106,6 +10129,28 @@ static int attempt_transfer(struct sip_pvt *p1, struct sip_pvt *p2)
return 0;
}
/*--- gettag: Get tag from packet */
static char *gettag(struct sip_request *req, char *header, char *tagbuf, int tagbufsize)
{
char *thetag, *sep;
if (!tagbuf)
return NULL;
tagbuf[0] = '\0'; /* reset the buffer */
thetag = get_header(req, header);
thetag = strcasestr(thetag, ";tag=");
if (thetag) {
thetag += 5;
ast_copy_string(tagbuf, thetag, tagbufsize);
sep = strchr(tagbuf, ';');
if (sep)
*sep = '\0';
}
return thetag;
}
/*--- handle_request_options: Handle incoming OPTIONS request */
static int handle_request_options(struct sip_pvt *p, struct sip_request *req, int debug)
{
@ -10209,6 +10254,7 @@ static int handle_request_invite(struct sip_pvt *p, struct sip_request *req, int
else
transmit_response_reliable(p, "403 Forbidden", req, 1);
ast_set_flag(p, SIP_NEEDDESTROY);
p->theirtag[0] = '\0'; /* Forget their to-tag, we'll get a new one */
}
return 0;
}
@ -10723,7 +10769,6 @@ static int handle_request(struct sip_pvt *p, struct sip_request *req, struct soc
struct sip_request resp;
char *cmd;
char *cseq;
char *from;
char *useragent;
int seqno;
int len;
@ -10789,12 +10834,14 @@ static int handle_request(struct sip_pvt *p, struct sip_request *req, struct soc
/* New SIP request coming in
(could be new request in existing SIP dialog as well...)
*/
p->method = req->method; /* Find out which SIP method they are using */
if (option_debug > 2)
ast_log(LOG_DEBUG, "**** Received %s (%d) - Command in SIP %s\n", sip_methods[p->method].text, sip_methods[p->method].id, cmd);
if (p->icseq && (p->icseq > seqno)) {
ast_log(LOG_DEBUG, "Ignoring too old SIP packet packet %d (expecting >= %d)\n", seqno, p->icseq);
transmit_response(p, "503 Server error", req); /* We must respond according to RFC 3261 sec 12.2 */
return -1;
} else if (p->icseq && (p->icseq == seqno) && req->method != SIP_ACK &&(p->method != SIP_CANCEL|| ast_test_flag(p, SIP_ALREADYGONE))) {
/* ignore means "don't do anything with it" but still have to
@ -10813,18 +10860,28 @@ static int handle_request(struct sip_pvt *p, struct sip_request *req, struct soc
/* Find their tag if we haven't got it */
if (ast_strlen_zero(p->theirtag)) {
from = get_header(req, "From");
from = strcasestr(from, "tag=");
if (from) {
from += 4;
ast_copy_string(p->theirtag, from, sizeof(p->theirtag));
from = strchr(p->theirtag, ';');
if (from)
*from = '\0';
}
gettag(req, "From", p->theirtag, sizeof(p->theirtag));
}
snprintf(p->lastmsg, sizeof(p->lastmsg), "Rx: %s", cmd);
if (pedanticsipchecking) {
/* If this is a request packet without a from tag, it's not
correct according to RFC 3261 */
/* Check if this a new request in a new dialog with a totag already attached to it,
RFC 3261 - section 12.2 - and we don't want to mess with recovery */
if (!p->initreq.headers && ast_test_flag(req, SIP_PKT_WITH_TOTAG)) {
/* If this is a first request and it got a to-tag, it is not for us */
if (!ignore && req->method == SIP_INVITE) {
transmit_response_reliable(p, "481 Call/Transaction Does Not Exist", req, 1);
/* Will cease to exist after ACK */
} else {
transmit_response(p, "481 Call/Transaction Does Not Exist", req);
ast_set_flag(p, SIP_NEEDDESTROY);
}
return res;
}
}
/* Handle various incoming SIP methods in requests */
switch (p->method) {
case SIP_OPTIONS:
@ -10921,14 +10978,16 @@ static int sipsock_read(int *id, int fd, short events, void *ignore)
}
req.data[res] = '\0';
req.len = res;
req.debug = sip_debug_test_addr(&sin);
if(sip_debug_test_addr(&sin))
ast_set_flag(&req, SIP_PKT_DEBUG);
if (pedanticsipchecking)
req.len = lws2sws(req.data, req.len); /* Fix multiline headers */
if (req.debug)
if (ast_test_flag(&req, SIP_PKT_DEBUG)) {
ast_verbose("\n<-- SIP read from %s:%d: \n%s\n", ast_inet_ntoa(iabuf, sizeof(iabuf), sin.sin_addr), ntohs(sin.sin_port), req.data);
}
parse_request(&req);
req.method = find_sip_method(req.rlPart1);
if (req.debug) {
if (ast_test_flag(&req, SIP_PKT_DEBUG)) {
ast_verbose("--- (%d headers %d lines)", req.headers, req.lines);
if (req.headers + req.lines == 0)
ast_verbose(" Nat keepalive ");

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