diff options
Diffstat (limited to 'channels/chan_sip.c')
| -rw-r--r-- | channels/chan_sip.c | 32 |
1 files changed, 25 insertions, 7 deletions
diff --git a/channels/chan_sip.c b/channels/chan_sip.c index ed12bf282..e81796af5 100644 --- a/channels/chan_sip.c +++ b/channels/chan_sip.c @@ -1809,6 +1809,7 @@ struct sip_pvt { struct ast_variable *notify_headers; /*!< Custom notify type */ struct sip_auth *peerauth; /*!< Realm authentication */ int noncecount; /*!< Nonce-count */ + unsigned int stalenonce:1; /*!< Marks the current nonce as responded too */ char lastmsg[256]; /*!< Last Message sent/received */ int amaflags; /*!< AMA Flags */ int pendinginvite; /*!< Any pending INVITE or state NOTIFY (in subscribe pvt's) ? (seqno of this) */ @@ -12505,6 +12506,20 @@ static void build_route(struct sip_pvt *p, struct sip_request *req, int backward list_route(p->route); } +/*! \brief builds the sip_pvt's randdata field which is used for the nonce + * challenge. When forceupdate is not set, the nonce is only updated if + * the current one is stale. In this case, a stalenonce is one which + * has already received a response, if a nonce has not received a response + * it is not always necessary or beneficial to create a new one. */ + +static void set_nonce_randdata(struct sip_pvt *p, int forceupdate) +{ + if (p->stalenonce || forceupdate || ast_strlen_zero(p->randdata)) { + ast_string_field_build(p, randdata, "%08lx", ast_random()); /* Create nonce for challenge */ + p->stalenonce = 0; + } +} + AST_THREADSTORAGE(check_auth_buf); #define CHECK_AUTH_BUF_INITLEN 256 @@ -12570,7 +12585,7 @@ static enum check_auth_result check_auth(struct sip_pvt *p, struct sip_request * return AUTH_CHALLENGE_SENT; } else if (ast_strlen_zero(p->randdata) || ast_strlen_zero(authtoken)) { /* We have no auth, so issue challenge and request authentication */ - ast_string_field_build(p, randdata, "%08lx", ast_random()); /* Create nonce for challenge */ + set_nonce_randdata(p, 1); /* Create nonce for challenge */ transmit_response_with_auth(p, response, req, p->randdata, reliable, respheader, 0); /* Schedule auto destroy in 32 seconds */ sip_scheddestroy(p, DEFAULT_TRANS_TIMEOUT); @@ -12621,10 +12636,13 @@ static enum check_auth_result check_auth(struct sip_pvt *p, struct sip_request * return AUTH_USERNAME_MISMATCH; } - /* Verify nonce from request matches our nonce. If not, send 401 with new nonce */ - if (strcasecmp(p->randdata, keys[K_NONCE].s)) { /* XXX it was 'n'casecmp ? */ + /* Verify nonce from request matches our nonce, and the nonce has not already been responded to. + * If this check fails, send 401 with new nonce */ + if (strcasecmp(p->randdata, keys[K_NONCE].s) || p->stalenonce) { /* XXX it was 'n'casecmp ? */ wrongnonce = TRUE; usednonce = keys[K_NONCE].s; + } else { + p->stalenonce = 1; /* now, since the nonce has a response, mark it as stale so it can't be sent or responded to again */ } if (!ast_strlen_zero(md5secret)) @@ -12655,14 +12673,14 @@ static enum check_auth_result check_auth(struct sip_pvt *p, struct sip_request * if (sipdebug) ast_log(LOG_NOTICE, "Correct auth, but based on stale nonce received from '%s'\n", get_header(req, "To")); /* We got working auth token, based on stale nonce . */ - ast_string_field_build(p, randdata, "%08lx", ast_random()); + set_nonce_randdata(p, 0); transmit_response_with_auth(p, response, req, p->randdata, reliable, respheader, TRUE); } else { /* Everything was wrong, so give the device one more try with a new challenge */ if (!req->ignore) { if (sipdebug) ast_log(LOG_NOTICE, "Bad authentication received from '%s'\n", get_header(req, "To")); - ast_string_field_build(p, randdata, "%08lx", ast_random()); + set_nonce_randdata(p, 1); } else { if (sipdebug) ast_log(LOG_NOTICE, "Duplicate authentication received from '%s'\n", get_header(req, "To")); @@ -12795,7 +12813,7 @@ static void transmit_fake_auth_response(struct sip_pvt *p, int sipmethod, struct return; } else if (ast_strlen_zero(p->randdata) || ast_strlen_zero(authtoken)) { /* We have no auth, so issue challenge and request authentication */ - ast_string_field_build(p, randdata, "%08lx", ast_random()); /* Create nonce for challenge */ + set_nonce_randdata(p, 1); transmit_response_with_auth(p, response, req, p->randdata, 0, respheader, 0); /* Schedule auto destroy in 32 seconds */ sip_scheddestroy(p, DEFAULT_TRANS_TIMEOUT); @@ -12840,7 +12858,7 @@ static void transmit_fake_auth_response(struct sip_pvt *p, int sipmethod, struct /* Verify nonce from request matches our nonce. If not, send 401 with new nonce */ if (strcasecmp(p->randdata, keys[K_NONCE].s)) { if (!req->ignore) { - ast_string_field_build(p, randdata, "%08lx", ast_random()); + set_nonce_randdata(p, 1); } transmit_response_with_auth(p, response, req, p->randdata, reliable, respheader, FALSE); |