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Let's repair the SIP attack shield :-) 

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@45743 65c4cc65-6c06-0410-ace0-fbb531ad65f3
This commit is contained in:
Olle Johansson 2006-10-20 08:14:14 +00:00
parent e19576388d
commit d6602b1b5e
1 changed files with 50 additions and 23 deletions
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73
channels/chan_sip.c
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@ -302,6 +302,7 @@ enum sipmethod {
SIP_INFO,
SIP_CANCEL,
SIP_PUBLISH, /* Not supported at all */
SIP_PING, /* Not supported at all, no standard but still implemented out there */
};
/*! \brief Authentication types - proxy or www authentication
@ -337,6 +338,9 @@ enum sipregistrystate {
REG_STATE_FAILED, /*!< Registration failed after several tries */
};
#define CAN_NOT_CREATE_DIALOG 0
#define CAN_CREATE_DIALOG 1
#define CAN_CREATE_DIALOG_UNSUPPORTED_METHOD 2
/*! XXX Note that sip_methods[i].id == i must hold or the code breaks */
static const struct cfsip_methods {
@ -345,22 +349,23 @@ static const struct cfsip_methods {
char * const text;
int can_create;
} sip_methods[] = {
{ SIP_UNKNOWN, RTP, "-UNKNOWN-", 0 },
{ SIP_RESPONSE, NO_RTP, "SIP/2.0", 0 },
{ SIP_REGISTER, NO_RTP, "REGISTER", 1 },
{ SIP_OPTIONS, NO_RTP, "OPTIONS", 1 },
{ SIP_NOTIFY, NO_RTP, "NOTIFY", 0 },
{ SIP_INVITE, RTP, "INVITE", 1 },
{ SIP_ACK, NO_RTP, "ACK", 0 },
{ SIP_PRACK, NO_RTP, "PRACK", 0 },
{ SIP_BYE, NO_RTP, "BYE", 0 },
{ SIP_REFER, NO_RTP, "REFER", 0 },
{ SIP_SUBSCRIBE, NO_RTP, "SUBSCRIBE", 1 },
{ SIP_MESSAGE, NO_RTP, "MESSAGE", 1 },
{ SIP_UPDATE, NO_RTP, "UPDATE", 0 },
{ SIP_INFO, NO_RTP, "INFO", 0 },
{ SIP_CANCEL, NO_RTP, "CANCEL", 0 },
{ SIP_PUBLISH, NO_RTP, "PUBLISH", 1 }
{ SIP_UNKNOWN, RTP, "-UNKNOWN-", CAN_CREATE_DIALOG },
{ SIP_RESPONSE, NO_RTP, "SIP/2.0", CAN_NOT_CREATE_DIALOG },
{ SIP_REGISTER, NO_RTP, "REGISTER", CAN_CREATE_DIALOG },
{ SIP_OPTIONS, NO_RTP, "OPTIONS", CAN_CREATE_DIALOG },
{ SIP_NOTIFY, NO_RTP, "NOTIFY", CAN_CREATE_DIALOG },
{ SIP_INVITE, RTP, "INVITE", CAN_CREATE_DIALOG },
{ SIP_ACK, NO_RTP, "ACK", CAN_NOT_CREATE_DIALOG },
{ SIP_PRACK, NO_RTP, "PRACK", CAN_NOT_CREATE_DIALOG },
{ SIP_BYE, NO_RTP, "BYE", CAN_NOT_CREATE_DIALOG },
{ SIP_REFER, NO_RTP, "REFER", CAN_CREATE_DIALOG },
{ SIP_SUBSCRIBE, NO_RTP, "SUBSCRIBE", CAN_CREATE_DIALOG },
{ SIP_MESSAGE, NO_RTP, "MESSAGE", CAN_CREATE_DIALOG },
{ SIP_UPDATE, NO_RTP, "UPDATE", CAN_NOT_CREATE_DIALOG },
{ SIP_INFO, NO_RTP, "INFO", CAN_NOT_CREATE_DIALOG },
{ SIP_CANCEL, NO_RTP, "CANCEL", CAN_NOT_CREATE_DIALOG },
{ SIP_PUBLISH, NO_RTP, "PUBLISH", CAN_CREATE_DIALOG_UNSUPPORTED_METHOD },
{ SIP_PING, NO_RTP, "PING", CAN_CREATE_DIALOG_UNSUPPORTED_METHOD }
};
/*! Define SIP option tags, used in Require: and Supported: headers
@ -4268,14 +4273,36 @@ static struct sip_pvt *find_call(struct sip_request *req, struct sockaddr_in *si
ast_mutex_unlock(&iflock);
/* See if the method is capable of creating a dialog */
if (!sip_methods[intended_method].can_create) {
if (intended_method != SIP_RESPONSE)
transmit_response_using_temp(callid, sin, 1, intended_method, req, "481 Call leg/transaction does not exist");
else if (option_debug > 1)
ast_log(LOG_DEBUG, "That's odd... Got a response on a call we dont know about. Callid %s\n", callid ? callid : "<unknown>");
} else if ((p = sip_alloc(callid, sin, 1, intended_method))) {
ast_mutex_lock(&p->lock);
if (sip_methods[intended_method].can_create == CAN_CREATE_DIALOG) {
if (intended_method == SIP_REFER) {
/* We do support REFER, but not outside of a dialog yet */
transmit_response_using_temp(callid, sin, 1, intended_method, req, "603 Declined (no dialog)");
} else if (intended_method == SIP_NOTIFY) {
/* We do not support out-of-dialog NOTIFY either,
like voicemail notification, so cancel that early */
transmit_response_using_temp(callid, sin, 1, intended_method, req, "489 Bad event");
} else {
/* Ok, time to create a new SIP dialog object, a pvt */
if ((p = sip_alloc(callid, sin, 1, intended_method)))
/* Ok, we've created a dialog, let's go and process it */
ast_mutex_lock(&p->lock);
}
return p;
} else if( sip_methods[intended_method].can_create == CAN_CREATE_DIALOG_UNSUPPORTED_METHOD) {
/* A method we do not support, let's take it on the volley */
transmit_response_using_temp(callid, sin, 1, intended_method, req, "501 Method Not Implemented");
if (option_debug > 1 )
ast_log(LOG_DEBUG, "Got a request with unsupported SIP method.\n");
} else if (intended_method != SIP_RESPONSE) {
/* This is a request outside of a dialog that we don't know about */
transmit_response_using_temp(callid, sin, 1, intended_method, req, "481 Call leg/transaction does not exist");
if (option_debug > 1 && intended_method == SIP_RESPONSE)
ast_log(LOG_DEBUG, "That's odd... Got a request in unknown dialog. Callid %s\n", callid ? callid : "<unknown>");
}
/* We do not respond to responses for dialogs that we don't know about, we just drop
the session quickly */
if (option_debug > 1 && intended_method == SIP_RESPONSE)
ast_log(LOG_DEBUG, "That's odd... Got a response on a call we dont know about. Callid %s\n", callid ? callid : "<unknown>");
return p;
}