/* * H.323 connection tracking helper * * Copyright (c) 2006 Jing Min Zhao * * This source code is licensed under General Public License version 2. * * Based on the 'brute force' H.323 connection tracking module by * Jozsef Kadlecsik * * For more information, please see http://nath323.sourceforge.net/ */ #include #include #include #include #include #include #include #include #include #include #include #if 0 #define DEBUGP printk #else #define DEBUGP(format, args...) #endif /* Parameters */ static unsigned int default_rrq_ttl = 300; module_param(default_rrq_ttl, uint, 0600); MODULE_PARM_DESC(default_rrq_ttl, "use this TTL if it's missing in RRQ"); static int gkrouted_only = 1; module_param(gkrouted_only, int, 0600); MODULE_PARM_DESC(gkrouted_only, "only accept calls from gatekeeper"); /* Hooks for NAT */ int (*set_h245_addr_hook) (struct sk_buff ** pskb, unsigned char **data, int dataoff, H245_TransportAddress * addr, u_int32_t ip, u_int16_t port); int (*set_h225_addr_hook) (struct sk_buff ** pskb, unsigned char **data, int dataoff, TransportAddress * addr, u_int32_t ip, u_int16_t port); int (*set_sig_addr_hook) (struct sk_buff ** pskb, struct ip_conntrack * ct, enum ip_conntrack_info ctinfo, unsigned char **data, TransportAddress * addr, int count); int (*set_ras_addr_hook) (struct sk_buff ** pskb, struct ip_conntrack * ct, enum ip_conntrack_info ctinfo, unsigned char **data, TransportAddress * addr, int count); int (*nat_rtp_rtcp_hook) (struct sk_buff ** pskb, struct ip_conntrack * ct, enum ip_conntrack_info ctinfo, unsigned char **data, int dataoff, H245_TransportAddress * addr, u_int16_t port, u_int16_t rtp_port, struct ip_conntrack_expect * rtp_exp, struct ip_conntrack_expect * rtcp_exp); int (*nat_t120_hook) (struct sk_buff ** pskb, struct ip_conntrack * ct, enum ip_conntrack_info ctinfo, unsigned char **data, int dataoff, H245_TransportAddress * addr, u_int16_t port, struct ip_conntrack_expect * exp); int (*nat_h245_hook) (struct sk_buff ** pskb, struct ip_conntrack * ct, enum ip_conntrack_info ctinfo, unsigned char **data, int dataoff, TransportAddress * addr, u_int16_t port, struct ip_conntrack_expect * exp); int (*nat_q931_hook) (struct sk_buff ** pskb, struct ip_conntrack * ct, enum ip_conntrack_info ctinfo, unsigned char **data, TransportAddress * addr, int idx, u_int16_t port, struct ip_conntrack_expect * exp); static DEFINE_SPINLOCK(ip_h323_lock); static char *h323_buffer; /****************************************************************************/ static int get_tpkt_data(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, int *datalen, int *dataoff) { struct ip_ct_h323_master *info = &ct->help.ct_h323_info; int dir = CTINFO2DIR(ctinfo); struct tcphdr _tcph, *th; int tcpdatalen; int tcpdataoff; unsigned char *tpkt; int tpktlen; int tpktoff; /* Get TCP header */ th = skb_header_pointer(*pskb, (*pskb)->nh.iph->ihl * 4, sizeof(_tcph), &_tcph); if (th == NULL) return 0; /* Get TCP data offset */ tcpdataoff = (*pskb)->nh.iph->ihl * 4 + th->doff * 4; /* Get TCP data length */ tcpdatalen = (*pskb)->len - tcpdataoff; if (tcpdatalen <= 0) /* No TCP data */ goto clear_out; if (*data == NULL) { /* first TPKT */ /* Get first TPKT pointer */ tpkt = skb_header_pointer(*pskb, tcpdataoff, tcpdatalen, h323_buffer); BUG_ON(tpkt == NULL); /* Validate TPKT identifier */ if (tcpdatalen < 4 || tpkt[0] != 0x03 || tpkt[1] != 0) { /* Netmeeting sends TPKT header and data separately */ if (info->tpkt_len[dir] > 0) { DEBUGP("ip_ct_h323: previous packet " "indicated separate TPKT data of %hu " "bytes\n", info->tpkt_len[dir]); if (info->tpkt_len[dir] <= tcpdatalen) { /* Yes, there was a TPKT header * received */ *data = tpkt; *datalen = info->tpkt_len[dir]; *dataoff = 0; goto out; } /* Fragmented TPKT */ if (net_ratelimit()) printk("ip_ct_h323: " "fragmented TPKT\n"); goto clear_out; } /* It is not even a TPKT */ return 0; } tpktoff = 0; } else { /* Next TPKT */ tpktoff = *dataoff + *datalen; tcpdatalen -= tpktoff; if (tcpdatalen <= 4) /* No more TPKT */ goto clear_out; tpkt = *data + *datalen; /* Validate TPKT identifier */ if (tpkt[0] != 0x03 || tpkt[1] != 0) goto clear_out; } /* Validate TPKT length */ tpktlen = tpkt[2] * 256 + tpkt[3]; if (tpktlen < 4) goto clear_out; if (tpktlen > tcpdatalen) { if (tcpdatalen == 4) { /* Separate TPKT header */ /* Netmeeting sends TPKT header and data separately */ DEBUGP("ip_ct_h323: separate TPKT header indicates " "there will be TPKT data of %hu bytes\n", tpktlen - 4); info->tpkt_len[dir] = tpktlen - 4; return 0; } if (net_ratelimit()) printk("ip_ct_h323: incomplete TPKT (fragmented?)\n"); goto clear_out; } /* This is the encapsulated data */ *data = tpkt + 4; *datalen = tpktlen - 4; *dataoff = tpktoff + 4; out: /* Clear TPKT length */ info->tpkt_len[dir] = 0; return 1; clear_out: info->tpkt_len[dir] = 0; return 0; } /****************************************************************************/ static int get_h245_addr(unsigned char *data, H245_TransportAddress * addr, u_int32_t * ip, u_int16_t * port) { unsigned char *p; if (addr->choice != eH245_TransportAddress_unicastAddress || addr->unicastAddress.choice != eUnicastAddress_iPAddress) return 0; p = data + addr->unicastAddress.iPAddress.network; *ip = htonl((p[0] << 24) | (p[1] << 16) | (p[2] << 8) | (p[3])); *port = (p[4] << 8) | (p[5]); return 1; } /****************************************************************************/ static int expect_rtp_rtcp(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, int dataoff, H245_TransportAddress * addr) { int dir = CTINFO2DIR(ctinfo); int ret = 0; u_int32_t ip; u_int16_t port; u_int16_t rtp_port; struct ip_conntrack_expect *rtp_exp; struct ip_conntrack_expect *rtcp_exp; /* Read RTP or RTCP address */ if (!get_h245_addr(*data, addr, &ip, &port) || ip != ct->tuplehash[dir].tuple.src.ip || port == 0) return 0; /* RTP port is even */ rtp_port = port & (~1); /* Create expect for RTP */ if ((rtp_exp = ip_conntrack_expect_alloc(ct)) == NULL) return -1; rtp_exp->tuple.src.ip = ct->tuplehash[!dir].tuple.src.ip; rtp_exp->tuple.src.u.udp.port = 0; rtp_exp->tuple.dst.ip = ct->tuplehash[!dir].tuple.dst.ip; rtp_exp->tuple.dst.u.udp.port = htons(rtp_port); rtp_exp->tuple.dst.protonum = IPPROTO_UDP; rtp_exp->mask.src.ip = 0xFFFFFFFF; rtp_exp->mask.src.u.udp.port = 0; rtp_exp->mask.dst.ip = 0xFFFFFFFF; rtp_exp->mask.dst.u.udp.port = 0xFFFF; rtp_exp->mask.dst.protonum = 0xFF; rtp_exp->flags = 0; /* Create expect for RTCP */ if ((rtcp_exp = ip_conntrack_expect_alloc(ct)) == NULL) { ip_conntrack_expect_put(rtp_exp); return -1; } rtcp_exp->tuple.src.ip = ct->tuplehash[!dir].tuple.src.ip; rtcp_exp->tuple.src.u.udp.port = 0; rtcp_exp->tuple.dst.ip = ct->tuplehash[!dir].tuple.dst.ip; rtcp_exp->tuple.dst.u.udp.port = htons(rtp_port + 1); rtcp_exp->tuple.dst.protonum = IPPROTO_UDP; rtcp_exp->mask.src.ip = 0xFFFFFFFF; rtcp_exp->mask.src.u.udp.port = 0; rtcp_exp->mask.dst.ip = 0xFFFFFFFF; rtcp_exp->mask.dst.u.udp.port = 0xFFFF; rtcp_exp->mask.dst.protonum = 0xFF; rtcp_exp->flags = 0; if (ct->tuplehash[dir].tuple.src.ip != ct->tuplehash[!dir].tuple.dst.ip && nat_rtp_rtcp_hook) { /* NAT needed */ ret = nat_rtp_rtcp_hook(pskb, ct, ctinfo, data, dataoff, addr, port, rtp_port, rtp_exp, rtcp_exp); } else { /* Conntrack only */ rtp_exp->expectfn = NULL; rtcp_exp->expectfn = NULL; if (ip_conntrack_expect_related(rtp_exp) == 0) { if (ip_conntrack_expect_related(rtcp_exp) == 0) { DEBUGP("ip_ct_h323: expect RTP " "%u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu\n", NIPQUAD(rtp_exp->tuple.src.ip), ntohs(rtp_exp->tuple.src.u.udp.port), NIPQUAD(rtp_exp->tuple.dst.ip), ntohs(rtp_exp->tuple.dst.u.udp.port)); DEBUGP("ip_ct_h323: expect RTCP " "%u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu\n", NIPQUAD(rtcp_exp->tuple.src.ip), ntohs(rtcp_exp->tuple.src.u.udp.port), NIPQUAD(rtcp_exp->tuple.dst.ip), ntohs(rtcp_exp->tuple.dst.u.udp.port)); } else { ip_conntrack_unexpect_related(rtp_exp); ret = -1; } } else ret = -1; } ip_conntrack_expect_put(rtp_exp); ip_conntrack_expect_put(rtcp_exp); return ret; } /****************************************************************************/ static int expect_t120(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, int dataoff, H245_TransportAddress * addr) { int dir = CTINFO2DIR(ctinfo); int ret = 0; u_int32_t ip; u_int16_t port; struct ip_conntrack_expect *exp = NULL; /* Read T.120 address */ if (!get_h245_addr(*data, addr, &ip, &port) || ip != ct->tuplehash[dir].tuple.src.ip || port == 0) return 0; /* Create expect for T.120 connections */ if ((exp = ip_conntrack_expect_alloc(ct)) == NULL) return -1; exp->tuple.src.ip = ct->tuplehash[!dir].tuple.src.ip; exp->tuple.src.u.tcp.port = 0; exp->tuple.dst.ip = ct->tuplehash[!dir].tuple.dst.ip; exp->tuple.dst.u.tcp.port = htons(port); exp->tuple.dst.protonum = IPPROTO_TCP; exp->mask.src.ip = 0xFFFFFFFF; exp->mask.src.u.tcp.port = 0; exp->mask.dst.ip = 0xFFFFFFFF; exp->mask.dst.u.tcp.port = 0xFFFF; exp->mask.dst.protonum = 0xFF; exp->flags = IP_CT_EXPECT_PERMANENT; /* Accept multiple channels */ if (ct->tuplehash[dir].tuple.src.ip != ct->tuplehash[!dir].tuple.dst.ip && nat_t120_hook) { /* NAT needed */ ret = nat_t120_hook(pskb, ct, ctinfo, data, dataoff, addr, port, exp); } else { /* Conntrack only */ exp->expectfn = NULL; if (ip_conntrack_expect_related(exp) == 0) { DEBUGP("ip_ct_h323: expect T.120 " "%u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu\n", NIPQUAD(exp->tuple.src.ip), ntohs(exp->tuple.src.u.tcp.port), NIPQUAD(exp->tuple.dst.ip), ntohs(exp->tuple.dst.u.tcp.port)); } else ret = -1; } ip_conntrack_expect_put(exp); return ret; } /****************************************************************************/ static int process_h245_channel(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, int dataoff, H2250LogicalChannelParameters * channel) { int ret; if (channel->options & eH2250LogicalChannelParameters_mediaChannel) { /* RTP */ ret = expect_rtp_rtcp(pskb, ct, ctinfo, data, dataoff, &channel->mediaChannel); if (ret < 0) return -1; } if (channel-> options & eH2250LogicalChannelParameters_mediaControlChannel) { /* RTCP */ ret = expect_rtp_rtcp(pskb, ct, ctinfo, data, dataoff, &channel->mediaControlChannel); if (ret < 0) return -1; } return 0; } /****************************************************************************/ static int process_olc(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, int dataoff, OpenLogicalChannel * olc) { int ret; DEBUGP("ip_ct_h323: OpenLogicalChannel\n"); if (olc->forwardLogicalChannelParameters.multiplexParameters.choice == eOpenLogicalChannel_forwardLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters) { ret = process_h245_channel(pskb, ct, ctinfo, data, dataoff, &olc-> forwardLogicalChannelParameters. multiplexParameters. h2250LogicalChannelParameters); if (ret < 0) return -1; } if ((olc->options & eOpenLogicalChannel_reverseLogicalChannelParameters) && (olc->reverseLogicalChannelParameters.options & eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters) && (olc->reverseLogicalChannelParameters.multiplexParameters. choice == eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters)) { ret = process_h245_channel(pskb, ct, ctinfo, data, dataoff, &olc-> reverseLogicalChannelParameters. multiplexParameters. h2250LogicalChannelParameters); if (ret < 0) return -1; } if ((olc->options & eOpenLogicalChannel_separateStack) && olc->forwardLogicalChannelParameters.dataType.choice == eDataType_data && olc->forwardLogicalChannelParameters.dataType.data.application. choice == eDataApplicationCapability_application_t120 && olc->forwardLogicalChannelParameters.dataType.data.application. t120.choice == eDataProtocolCapability_separateLANStack && olc->separateStack.networkAddress.choice == eNetworkAccessParameters_networkAddress_localAreaAddress) { ret = expect_t120(pskb, ct, ctinfo, data, dataoff, &olc->separateStack.networkAddress. localAreaAddress); if (ret < 0) return -1; } return 0; } /****************************************************************************/ static int process_olca(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, int dataoff, OpenLogicalChannelAck * olca) { H2250LogicalChannelAckParameters *ack; int ret; DEBUGP("ip_ct_h323: OpenLogicalChannelAck\n"); if ((olca->options & eOpenLogicalChannelAck_reverseLogicalChannelParameters) && (olca->reverseLogicalChannelParameters.options & eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters) && (olca->reverseLogicalChannelParameters.multiplexParameters. choice == eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters)) { ret = process_h245_channel(pskb, ct, ctinfo, data, dataoff, &olca-> reverseLogicalChannelParameters. multiplexParameters. h2250LogicalChannelParameters); if (ret < 0) return -1; } if ((olca->options & eOpenLogicalChannelAck_forwardMultiplexAckParameters) && (olca->forwardMultiplexAckParameters.choice == eOpenLogicalChannelAck_forwardMultiplexAckParameters_h2250LogicalChannelAckParameters)) { ack = &olca->forwardMultiplexAckParameters. h2250LogicalChannelAckParameters; if (ack->options & eH2250LogicalChannelAckParameters_mediaChannel) { /* RTP */ ret = expect_rtp_rtcp(pskb, ct, ctinfo, data, dataoff, &ack->mediaChannel); if (ret < 0) return -1; } if (ack->options & eH2250LogicalChannelAckParameters_mediaControlChannel) { /* RTCP */ ret = expect_rtp_rtcp(pskb, ct, ctinfo, data, dataoff, &ack->mediaControlChannel); if (ret < 0) return -1; } } return 0; } /****************************************************************************/ static int process_h245(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, int dataoff, MultimediaSystemControlMessage * mscm) { switch (mscm->choice) { case eMultimediaSystemControlMessage_request: if (mscm->request.choice == eRequestMessage_openLogicalChannel) { return process_olc(pskb, ct, ctinfo, data, dataoff, &mscm->request.openLogicalChannel); } DEBUGP("ip_ct_h323: H.245 Request %d\n", mscm->request.choice); break; case eMultimediaSystemControlMessage_response: if (mscm->response.choice == eResponseMessage_openLogicalChannelAck) { return process_olca(pskb, ct, ctinfo, data, dataoff, &mscm->response. openLogicalChannelAck); } DEBUGP("ip_ct_h323: H.245 Response %d\n", mscm->response.choice); break; default: DEBUGP("ip_ct_h323: H.245 signal %d\n", mscm->choice); break; } return 0; } /****************************************************************************/ static int h245_help(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo) { static MultimediaSystemControlMessage mscm; unsigned char *data = NULL; int datalen; int dataoff; int ret; /* Until there's been traffic both ways, don't look in packets. */ if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) { return NF_ACCEPT; } DEBUGP("ip_ct_h245: skblen = %u\n", (*pskb)->len); spin_lock_bh(&ip_h323_lock); /* Process each TPKT */ while (get_tpkt_data(pskb, ct, ctinfo, &data, &datalen, &dataoff)) { DEBUGP("ip_ct_h245: TPKT %u.%u.%u.%u->%u.%u.%u.%u, len=%d\n", NIPQUAD((*pskb)->nh.iph->saddr), NIPQUAD((*pskb)->nh.iph->daddr), datalen); /* Decode H.245 signal */ ret = DecodeMultimediaSystemControlMessage(data, datalen, &mscm); if (ret < 0) { if (net_ratelimit()) printk("ip_ct_h245: decoding error: %s\n", ret == H323_ERROR_BOUND ? "out of bound" : "out of range"); /* We don't drop when decoding error */ break; } /* Process H.245 signal */ if (process_h245(pskb, ct, ctinfo, &data, dataoff, &mscm) < 0) goto drop; } spin_unlock_bh(&ip_h323_lock); return NF_ACCEPT; drop: spin_unlock_bh(&ip_h323_lock); if (net_ratelimit()) printk("ip_ct_h245: packet dropped\n"); return NF_DROP; } /****************************************************************************/ static struct ip_conntrack_helper ip_conntrack_helper_h245 = { .name = "H.245", .me = THIS_MODULE, .max_expected = H323_RTP_CHANNEL_MAX * 4 + 2 /* T.120 */ , .timeout = 240, .tuple = {.dst = {.protonum = IPPROTO_TCP}}, .mask = {.src = {.u = {0xFFFF}}, .dst = {.protonum = 0xFF}}, .help = h245_help }; /****************************************************************************/ void ip_conntrack_h245_expect(struct ip_conntrack *new, struct ip_conntrack_expect *this) { write_lock_bh(&ip_conntrack_lock); new->helper = &ip_conntrack_helper_h245; write_unlock_bh(&ip_conntrack_lock); } /****************************************************************************/ int get_h225_addr(unsigned char *data, TransportAddress * addr, u_int32_t * ip, u_int16_t * port) { unsigned char *p; if (addr->choice != eTransportAddress_ipAddress) return 0; p = data + addr->ipAddress.ip; *ip = htonl((p[0] << 24) | (p[1] << 16) | (p[2] << 8) | (p[3])); *port = (p[4] << 8) | (p[5]); return 1; } /****************************************************************************/ static int expect_h245(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, int dataoff, TransportAddress * addr) { int dir = CTINFO2DIR(ctinfo); int ret = 0; u_int32_t ip; u_int16_t port; struct ip_conntrack_expect *exp = NULL; /* Read h245Address */ if (!get_h225_addr(*data, addr, &ip, &port) || ip != ct->tuplehash[dir].tuple.src.ip || port == 0) return 0; /* Create expect for h245 connection */ if ((exp = ip_conntrack_expect_alloc(ct)) == NULL) return -1; exp->tuple.src.ip = ct->tuplehash[!dir].tuple.src.ip; exp->tuple.src.u.tcp.port = 0; exp->tuple.dst.ip = ct->tuplehash[!dir].tuple.dst.ip; exp->tuple.dst.u.tcp.port = htons(port); exp->tuple.dst.protonum = IPPROTO_TCP; exp->mask.src.ip = 0xFFFFFFFF; exp->mask.src.u.tcp.port = 0; exp->mask.dst.ip = 0xFFFFFFFF; exp->mask.dst.u.tcp.port = 0xFFFF; exp->mask.dst.protonum = 0xFF; exp->flags = 0; if (ct->tuplehash[dir].tuple.src.ip != ct->tuplehash[!dir].tuple.dst.ip && nat_h245_hook) { /* NAT needed */ ret = nat_h245_hook(pskb, ct, ctinfo, data, dataoff, addr, port, exp); } else { /* Conntrack only */ exp->expectfn = ip_conntrack_h245_expect; if (ip_conntrack_expect_related(exp) == 0) { DEBUGP("ip_ct_q931: expect H.245 " "%u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu\n", NIPQUAD(exp->tuple.src.ip), ntohs(exp->tuple.src.u.tcp.port), NIPQUAD(exp->tuple.dst.ip), ntohs(exp->tuple.dst.u.tcp.port)); } else ret = -1; } ip_conntrack_expect_put(exp); return ret; } /****************************************************************************/ static int process_setup(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, int dataoff, Setup_UUIE * setup) { int dir = CTINFO2DIR(ctinfo); int ret; int i; u_int32_t ip; u_int16_t port; DEBUGP("ip_ct_q931: Setup\n"); if (setup->options & eSetup_UUIE_h245Address) { ret = expect_h245(pskb, ct, ctinfo, data, dataoff, &setup->h245Address); if (ret < 0) return -1; } if ((setup->options & eSetup_UUIE_destCallSignalAddress) && (set_h225_addr_hook) && get_h225_addr(*data, &setup->destCallSignalAddress, &ip, &port) && ip != ct->tuplehash[!dir].tuple.src.ip) { DEBUGP("ip_ct_q931: set destCallSignalAddress " "%u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu\n", NIPQUAD(ip), port, NIPQUAD(ct->tuplehash[!dir].tuple.src.ip), ntohs(ct->tuplehash[!dir].tuple.src.u.tcp.port)); ret = set_h225_addr_hook(pskb, data, dataoff, &setup->destCallSignalAddress, ct->tuplehash[!dir].tuple.src.ip, ntohs(ct->tuplehash[!dir].tuple.src. u.tcp.port)); if (ret < 0) return -1; } if ((setup->options & eSetup_UUIE_sourceCallSignalAddress) && (set_h225_addr_hook) && get_h225_addr(*data, &setup->sourceCallSignalAddress, &ip, &port) && ip != ct->tuplehash[!dir].tuple.dst.ip) { DEBUGP("ip_ct_q931: set sourceCallSignalAddress " "%u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu\n", NIPQUAD(ip), port, NIPQUAD(ct->tuplehash[!dir].tuple.dst.ip), ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port)); ret = set_h225_addr_hook(pskb, data, dataoff, &setup->sourceCallSignalAddress, ct->tuplehash[!dir].tuple.dst.ip, ntohs(ct->tuplehash[!dir].tuple.dst. u.tcp.port)); if (ret < 0) return -1; } if (setup->options & eSetup_UUIE_fastStart) { for (i = 0; i < setup->fastStart.count; i++) { ret = process_olc(pskb, ct, ctinfo, data, dataoff, &setup->fastStart.item[i]); if (ret < 0) return -1; } } return 0; } /****************************************************************************/ static int process_callproceeding(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, int dataoff, CallProceeding_UUIE * callproc) { int ret; int i; DEBUGP("ip_ct_q931: CallProceeding\n"); if (callproc->options & eCallProceeding_UUIE_h245Address) { ret = expect_h245(pskb, ct, ctinfo, data, dataoff, &callproc->h245Address); if (ret < 0) return -1; } if (callproc->options & eCallProceeding_UUIE_fastStart) { for (i = 0; i < callproc->fastStart.count; i++) { ret = process_olc(pskb, ct, ctinfo, data, dataoff, &callproc->fastStart.item[i]); if (ret < 0) return -1; } } return 0; } /****************************************************************************/ static int process_connect(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, int dataoff, Connect_UUIE * connect) { int ret; int i; DEBUGP("ip_ct_q931: Connect\n"); if (connect->options & eConnect_UUIE_h245Address) { ret = expect_h245(pskb, ct, ctinfo, data, dataoff, &connect->h245Address); if (ret < 0) return -1; } if (connect->options & eConnect_UUIE_fastStart) { for (i = 0; i < connect->fastStart.count; i++) { ret = process_olc(pskb, ct, ctinfo, data, dataoff, &connect->fastStart.item[i]); if (ret < 0) return -1; } } return 0; } /****************************************************************************/ static int process_alerting(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, int dataoff, Alerting_UUIE * alert) { int ret; int i; DEBUGP("ip_ct_q931: Alerting\n"); if (alert->options & eAlerting_UUIE_h245Address) { ret = expect_h245(pskb, ct, ctinfo, data, dataoff, &alert->h245Address); if (ret < 0) return -1; } if (alert->options & eAlerting_UUIE_fastStart) { for (i = 0; i < alert->fastStart.count; i++) { ret = process_olc(pskb, ct, ctinfo, data, dataoff, &alert->fastStart.item[i]); if (ret < 0) return -1; } } return 0; } /****************************************************************************/ static int process_information(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, int dataoff, Information_UUIE * info) { int ret; int i; DEBUGP("ip_ct_q931: Information\n"); if (info->options & eInformation_UUIE_fastStart) { for (i = 0; i < info->fastStart.count; i++) { ret = process_olc(pskb, ct, ctinfo, data, dataoff, &info->fastStart.item[i]); if (ret < 0) return -1; } } return 0; } /****************************************************************************/ static int process_facility(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, int dataoff, Facility_UUIE * facility) { int ret; int i; DEBUGP("ip_ct_q931: Facility\n"); if (facility->options & eFacility_UUIE_h245Address) { ret = expect_h245(pskb, ct, ctinfo, data, dataoff, &facility->h245Address); if (ret < 0) return -1; } if (facility->options & eFacility_UUIE_fastStart) { for (i = 0; i < facility->fastStart.count; i++) { ret = process_olc(pskb, ct, ctinfo, data, dataoff, &facility->fastStart.item[i]); if (ret < 0) return -1; } } return 0; } /****************************************************************************/ static int process_progress(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, int dataoff, Progress_UUIE * progress) { int ret; int i; DEBUGP("ip_ct_q931: Progress\n"); if (progress->options & eProgress_UUIE_h245Address) { ret = expect_h245(pskb, ct, ctinfo, data, dataoff, &progress->h245Address); if (ret < 0) return -1; } if (progress->options & eProgress_UUIE_fastStart) { for (i = 0; i < progress->fastStart.count; i++) { ret = process_olc(pskb, ct, ctinfo, data, dataoff, &progress->fastStart.item[i]); if (ret < 0) return -1; } } return 0; } /****************************************************************************/ static int process_q931(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, int dataoff, Q931 * q931) { H323_UU_PDU *pdu = &q931->UUIE.h323_uu_pdu; int i; int ret = 0; switch (pdu->h323_message_body.choice) { case eH323_UU_PDU_h323_message_body_setup: ret = process_setup(pskb, ct, ctinfo, data, dataoff, &pdu->h323_message_body.setup); break; case eH323_UU_PDU_h323_message_body_callProceeding: ret = process_callproceeding(pskb, ct, ctinfo, data, dataoff, &pdu->h323_message_body. callProceeding); break; case eH323_UU_PDU_h323_message_body_connect: ret = process_connect(pskb, ct, ctinfo, data, dataoff, &pdu->h323_message_body.connect); break; case eH323_UU_PDU_h323_message_body_alerting: ret = process_alerting(pskb, ct, ctinfo, data, dataoff, &pdu->h323_message_body.alerting); break; case eH323_UU_PDU_h323_message_body_information: ret = process_information(pskb, ct, ctinfo, data, dataoff, &pdu->h323_message_body. information); break; case eH323_UU_PDU_h323_message_body_facility: ret = process_facility(pskb, ct, ctinfo, data, dataoff, &pdu->h323_message_body.facility); break; case eH323_UU_PDU_h323_message_body_progress: ret = process_progress(pskb, ct, ctinfo, data, dataoff, &pdu->h323_message_body.progress); break; default: DEBUGP("ip_ct_q931: Q.931 signal %d\n", pdu->h323_message_body.choice); break; } if (ret < 0) return -1; if (pdu->options & eH323_UU_PDU_h245Control) { for (i = 0; i < pdu->h245Control.count; i++) { ret = process_h245(pskb, ct, ctinfo, data, dataoff, &pdu->h245Control.item[i]); if (ret < 0) return -1; } } return 0; } /****************************************************************************/ static int q931_help(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo) { static Q931 q931; unsigned char *data = NULL; int datalen; int dataoff; int ret; /* Until there's been traffic both ways, don't look in packets. */ if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) { return NF_ACCEPT; } DEBUGP("ip_ct_q931: skblen = %u\n", (*pskb)->len); spin_lock_bh(&ip_h323_lock); /* Process each TPKT */ while (get_tpkt_data(pskb, ct, ctinfo, &data, &datalen, &dataoff)) { DEBUGP("ip_ct_q931: TPKT %u.%u.%u.%u->%u.%u.%u.%u, len=%d\n", NIPQUAD((*pskb)->nh.iph->saddr), NIPQUAD((*pskb)->nh.iph->daddr), datalen); /* Decode Q.931 signal */ ret = DecodeQ931(data, datalen, &q931); if (ret < 0) { if (net_ratelimit()) printk("ip_ct_q931: decoding error: %s\n", ret == H323_ERROR_BOUND ? "out of bound" : "out of range"); /* We don't drop when decoding error */ break; } /* Process Q.931 signal */ if (process_q931(pskb, ct, ctinfo, &data, dataoff, &q931) < 0) goto drop; } spin_unlock_bh(&ip_h323_lock); return NF_ACCEPT; drop: spin_unlock_bh(&ip_h323_lock); if (net_ratelimit()) printk("ip_ct_q931: packet dropped\n"); return NF_DROP; } /****************************************************************************/ static struct ip_conntrack_helper ip_conntrack_helper_q931 = { .name = "Q.931", .me = THIS_MODULE, .max_expected = H323_RTP_CHANNEL_MAX * 4 + 4 /* T.120 and H.245 */ , .timeout = 240, .tuple = {.src = {.u = {__constant_htons(Q931_PORT)}}, .dst = {.protonum = IPPROTO_TCP}}, .mask = {.src = {.u = {0xFFFF}}, .dst = {.protonum = 0xFF}}, .help = q931_help }; /****************************************************************************/ void ip_conntrack_q931_expect(struct ip_conntrack *new, struct ip_conntrack_expect *this) { write_lock_bh(&ip_conntrack_lock); new->helper = &ip_conntrack_helper_q931; write_unlock_bh(&ip_conntrack_lock); } /****************************************************************************/ static unsigned char *get_udp_data(struct sk_buff **pskb, int *datalen) { struct udphdr _uh, *uh; int dataoff; uh = skb_header_pointer(*pskb, (*pskb)->nh.iph->ihl * 4, sizeof(_uh), &_uh); if (uh == NULL) return NULL; dataoff = (*pskb)->nh.iph->ihl * 4 + sizeof(_uh); if (dataoff >= (*pskb)->len) return NULL; *datalen = (*pskb)->len - dataoff; return skb_header_pointer(*pskb, dataoff, *datalen, h323_buffer); } /****************************************************************************/ static struct ip_conntrack_expect *find_expect(struct ip_conntrack *ct, u_int32_t ip, u_int16_t port) { struct ip_conntrack_expect *exp; struct ip_conntrack_tuple tuple; tuple.src.ip = 0; tuple.src.u.tcp.port = 0; tuple.dst.ip = ip; tuple.dst.u.tcp.port = htons(port); tuple.dst.protonum = IPPROTO_TCP; exp = __ip_conntrack_expect_find(&tuple); if (exp->master == ct) return exp; return NULL; } /****************************************************************************/ static int set_expect_timeout(struct ip_conntrack_expect *exp, unsigned timeout) { if (!exp || !del_timer(&exp->timeout)) return 0; exp->timeout.expires = jiffies + timeout * HZ; add_timer(&exp->timeout); return 1; } /****************************************************************************/ static int expect_q931(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, TransportAddress * addr, int count) { struct ip_ct_h323_master *info = &ct->help.ct_h323_info; int dir = CTINFO2DIR(ctinfo); int ret = 0; int i; u_int32_t ip; u_int16_t port; struct ip_conntrack_expect *exp; /* Look for the first related address */ for (i = 0; i < count; i++) { if (get_h225_addr(*data, &addr[i], &ip, &port) && ip == ct->tuplehash[dir].tuple.src.ip && port != 0) break; } if (i >= count) /* Not found */ return 0; /* Create expect for Q.931 */ if ((exp = ip_conntrack_expect_alloc(ct)) == NULL) return -1; exp->tuple.src.ip = gkrouted_only ? /* only accept calls from GK? */ ct->tuplehash[!dir].tuple.src.ip : 0; exp->tuple.src.u.tcp.port = 0; exp->tuple.dst.ip = ct->tuplehash[!dir].tuple.dst.ip; exp->tuple.dst.u.tcp.port = htons(port); exp->tuple.dst.protonum = IPPROTO_TCP; exp->mask.src.ip = gkrouted_only ? 0xFFFFFFFF : 0; exp->mask.src.u.tcp.port = 0; exp->mask.dst.ip = 0xFFFFFFFF; exp->mask.dst.u.tcp.port = 0xFFFF; exp->mask.dst.protonum = 0xFF; exp->flags = IP_CT_EXPECT_PERMANENT; /* Accept multiple calls */ if (nat_q931_hook) { /* Need NAT */ ret = nat_q931_hook(pskb, ct, ctinfo, data, addr, i, port, exp); } else { /* Conntrack only */ exp->expectfn = ip_conntrack_q931_expect; if (ip_conntrack_expect_related(exp) == 0) { DEBUGP("ip_ct_ras: expect Q.931 " "%u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu\n", NIPQUAD(exp->tuple.src.ip), ntohs(exp->tuple.src.u.tcp.port), NIPQUAD(exp->tuple.dst.ip), ntohs(exp->tuple.dst.u.tcp.port)); /* Save port for looking up expect in processing RCF */ info->sig_port[dir] = port; } else ret = -1; } ip_conntrack_expect_put(exp); return ret; } /****************************************************************************/ static int process_grq(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, GatekeeperRequest * grq) { DEBUGP("ip_ct_ras: GRQ\n"); if (set_ras_addr_hook) /* NATed */ return set_ras_addr_hook(pskb, ct, ctinfo, data, &grq->rasAddress, 1); return 0; } /* Declare before using */ static void ip_conntrack_ras_expect(struct ip_conntrack *new, struct ip_conntrack_expect *this); /****************************************************************************/ static int process_gcf(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, GatekeeperConfirm * gcf) { int dir = CTINFO2DIR(ctinfo); int ret = 0; u_int32_t ip; u_int16_t port; struct ip_conntrack_expect *exp; DEBUGP("ip_ct_ras: GCF\n"); if (!get_h225_addr(*data, &gcf->rasAddress, &ip, &port)) return 0; /* Registration port is the same as discovery port */ if (ip == ct->tuplehash[dir].tuple.src.ip && port == ntohs(ct->tuplehash[dir].tuple.src.u.udp.port)) return 0; /* Avoid RAS expectation loops. A GCF is never expected. */ if (test_bit(IPS_EXPECTED_BIT, &ct->status)) return 0; /* Need new expect */ if ((exp = ip_conntrack_expect_alloc(ct)) == NULL) return -1; exp->tuple.src.ip = ct->tuplehash[!dir].tuple.src.ip; exp->tuple.src.u.tcp.port = 0; exp->tuple.dst.ip = ip; exp->tuple.dst.u.tcp.port = htons(port); exp->tuple.dst.protonum = IPPROTO_UDP; exp->mask.src.ip = 0xFFFFFFFF; exp->mask.src.u.tcp.port = 0; exp->mask.dst.ip = 0xFFFFFFFF; exp->mask.dst.u.tcp.port = 0xFFFF; exp->mask.dst.protonum = 0xFF; exp->flags = 0; exp->expectfn = ip_conntrack_ras_expect; if (ip_conntrack_expect_related(exp) == 0) { DEBUGP("ip_ct_ras: expect RAS " "%u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu\n", NIPQUAD(exp->tuple.src.ip), ntohs(exp->tuple.src.u.tcp.port), NIPQUAD(exp->tuple.dst.ip), ntohs(exp->tuple.dst.u.tcp.port)); } else ret = -1; ip_conntrack_expect_put(exp); return ret; } /****************************************************************************/ static int process_rrq(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, RegistrationRequest * rrq) { struct ip_ct_h323_master *info = &ct->help.ct_h323_info; int ret; DEBUGP("ip_ct_ras: RRQ\n"); ret = expect_q931(pskb, ct, ctinfo, data, rrq->callSignalAddress.item, rrq->callSignalAddress.count); if (ret < 0) return -1; if (set_ras_addr_hook) { ret = set_ras_addr_hook(pskb, ct, ctinfo, data, rrq->rasAddress.item, rrq->rasAddress.count); if (ret < 0) return -1; } if (rrq->options & eRegistrationRequest_timeToLive) { DEBUGP("ip_ct_ras: RRQ TTL = %u seconds\n", rrq->timeToLive); info->timeout = rrq->timeToLive; } else info->timeout = default_rrq_ttl; return 0; } /****************************************************************************/ static int process_rcf(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, RegistrationConfirm * rcf) { struct ip_ct_h323_master *info = &ct->help.ct_h323_info; int dir = CTINFO2DIR(ctinfo); int ret; struct ip_conntrack_expect *exp; DEBUGP("ip_ct_ras: RCF\n"); if (set_sig_addr_hook) { ret = set_sig_addr_hook(pskb, ct, ctinfo, data, rcf->callSignalAddress.item, rcf->callSignalAddress.count); if (ret < 0) return -1; } if (rcf->options & eRegistrationConfirm_timeToLive) { DEBUGP("ip_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive); info->timeout = rcf->timeToLive; } if (info->timeout > 0) { DEBUGP ("ip_ct_ras: set RAS connection timeout to %u seconds\n", info->timeout); ip_ct_refresh_acct(ct, ctinfo, NULL, info->timeout * HZ); /* Set expect timeout */ read_lock_bh(&ip_conntrack_lock); exp = find_expect(ct, ct->tuplehash[dir].tuple.dst.ip, info->sig_port[!dir]); if (exp) { DEBUGP("ip_ct_ras: set Q.931 expect " "(%u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu) " "timeout to %u seconds\n", NIPQUAD(exp->tuple.src.ip), ntohs(exp->tuple.src.u.tcp.port), NIPQUAD(exp->tuple.dst.ip), ntohs(exp->tuple.dst.u.tcp.port), info->timeout); set_expect_timeout(exp, info->timeout); } read_unlock_bh(&ip_conntrack_lock); } return 0; } /****************************************************************************/ static int process_urq(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, UnregistrationRequest * urq) { struct ip_ct_h323_master *info = &ct->help.ct_h323_info; int dir = CTINFO2DIR(ctinfo); int ret; DEBUGP("ip_ct_ras: URQ\n"); if (set_sig_addr_hook) { ret = set_sig_addr_hook(pskb, ct, ctinfo, data, urq->callSignalAddress.item, urq->callSignalAddress.count); if (ret < 0) return -1; } /* Clear old expect */ ip_ct_remove_expectations(ct); info->sig_port[dir] = 0; info->sig_port[!dir] = 0; /* Give it 30 seconds for UCF or URJ */ ip_ct_refresh_acct(ct, ctinfo, NULL, 30 * HZ); return 0; } /****************************************************************************/ static int process_arq(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, AdmissionRequest * arq) { struct ip_ct_h323_master *info = &ct->help.ct_h323_info; int dir = CTINFO2DIR(ctinfo); u_int32_t ip; u_int16_t port; DEBUGP("ip_ct_ras: ARQ\n"); if ((arq->options & eAdmissionRequest_destCallSignalAddress) && get_h225_addr(*data, &arq->destCallSignalAddress, &ip, &port) && ip == ct->tuplehash[dir].tuple.src.ip && port == info->sig_port[dir] && set_h225_addr_hook) { /* Answering ARQ */ return set_h225_addr_hook(pskb, data, 0, &arq->destCallSignalAddress, ct->tuplehash[!dir].tuple.dst.ip, info->sig_port[!dir]); } if ((arq->options & eAdmissionRequest_srcCallSignalAddress) && get_h225_addr(*data, &arq->srcCallSignalAddress, &ip, &port) && ip == ct->tuplehash[dir].tuple.src.ip && set_h225_addr_hook) { /* Calling ARQ */ return set_h225_addr_hook(pskb, data, 0, &arq->srcCallSignalAddress, ct->tuplehash[!dir].tuple.dst.ip, port); } return 0; } /****************************************************************************/ static int process_acf(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, AdmissionConfirm * acf) { int dir = CTINFO2DIR(ctinfo); int ret = 0; u_int32_t ip; u_int16_t port; struct ip_conntrack_expect *exp; DEBUGP("ip_ct_ras: ACF\n"); if (!get_h225_addr(*data, &acf->destCallSignalAddress, &ip, &port)) return 0; if (ip == ct->tuplehash[dir].tuple.dst.ip) { /* Answering ACF */ if (set_sig_addr_hook) return set_sig_addr_hook(pskb, ct, ctinfo, data, &acf->destCallSignalAddress, 1); return 0; } /* Need new expect */ if ((exp = ip_conntrack_expect_alloc(ct)) == NULL) return -1; exp->tuple.src.ip = ct->tuplehash[!dir].tuple.src.ip; exp->tuple.src.u.tcp.port = 0; exp->tuple.dst.ip = ip; exp->tuple.dst.u.tcp.port = htons(port); exp->tuple.dst.protonum = IPPROTO_TCP; exp->mask.src.ip = 0xFFFFFFFF; exp->mask.src.u.tcp.port = 0; exp->mask.dst.ip = 0xFFFFFFFF; exp->mask.dst.u.tcp.port = 0xFFFF; exp->mask.dst.protonum = 0xFF; exp->flags = IP_CT_EXPECT_PERMANENT; exp->expectfn = ip_conntrack_q931_expect; if (ip_conntrack_expect_related(exp) == 0) { DEBUGP("ip_ct_ras: expect Q.931 " "%u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu\n", NIPQUAD(exp->tuple.src.ip), ntohs(exp->tuple.src.u.tcp.port), NIPQUAD(exp->tuple.dst.ip), ntohs(exp->tuple.dst.u.tcp.port)); } else ret = -1; ip_conntrack_expect_put(exp); return ret; } /****************************************************************************/ static int process_lrq(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, LocationRequest * lrq) { DEBUGP("ip_ct_ras: LRQ\n"); if (set_ras_addr_hook) return set_ras_addr_hook(pskb, ct, ctinfo, data, &lrq->replyAddress, 1); return 0; } /****************************************************************************/ static int process_lcf(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, LocationConfirm * lcf) { int dir = CTINFO2DIR(ctinfo); int ret = 0; u_int32_t ip; u_int16_t port; struct ip_conntrack_expect *exp = NULL; DEBUGP("ip_ct_ras: LCF\n"); if (!get_h225_addr(*data, &lcf->callSignalAddress, &ip, &port)) return 0; /* Need new expect for call signal */ if ((exp = ip_conntrack_expect_alloc(ct)) == NULL) return -1; exp->tuple.src.ip = ct->tuplehash[!dir].tuple.src.ip; exp->tuple.src.u.tcp.port = 0; exp->tuple.dst.ip = ip; exp->tuple.dst.u.tcp.port = htons(port); exp->tuple.dst.protonum = IPPROTO_TCP; exp->mask.src.ip = 0xFFFFFFFF; exp->mask.src.u.tcp.port = 0; exp->mask.dst.ip = 0xFFFFFFFF; exp->mask.dst.u.tcp.port = 0xFFFF; exp->mask.dst.protonum = 0xFF; exp->flags = IP_CT_EXPECT_PERMANENT; exp->expectfn = ip_conntrack_q931_expect; if (ip_conntrack_expect_related(exp) == 0) { DEBUGP("ip_ct_ras: expect Q.931 " "%u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu\n", NIPQUAD(exp->tuple.src.ip), ntohs(exp->tuple.src.u.tcp.port), NIPQUAD(exp->tuple.dst.ip), ntohs(exp->tuple.dst.u.tcp.port)); } else ret = -1; ip_conntrack_expect_put(exp); /* Ignore rasAddress */ return ret; } /****************************************************************************/ static int process_irr(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, InfoRequestResponse * irr) { int ret; DEBUGP("ip_ct_ras: IRR\n"); if (set_ras_addr_hook) { ret = set_ras_addr_hook(pskb, ct, ctinfo, data, &irr->rasAddress, 1); if (ret < 0) return -1; } if (set_sig_addr_hook) { ret = set_sig_addr_hook(pskb, ct, ctinfo, data, irr->callSignalAddress.item, irr->callSignalAddress.count); if (ret < 0) return -1; } return 0; } /****************************************************************************/ static int process_ras(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, unsigned char **data, RasMessage * ras) { switch (ras->choice) { case eRasMessage_gatekeeperRequest: return process_grq(pskb, ct, ctinfo, data, &ras->gatekeeperRequest); case eRasMessage_gatekeeperConfirm: return process_gcf(pskb, ct, ctinfo, data, &ras->gatekeeperConfirm); case eRasMessage_registrationRequest: return process_rrq(pskb, ct, ctinfo, data, &ras->registrationRequest); case eRasMessage_registrationConfirm: return process_rcf(pskb, ct, ctinfo, data, &ras->registrationConfirm); case eRasMessage_unregistrationRequest: return process_urq(pskb, ct, ctinfo, data, &ras->unregistrationRequest); case eRasMessage_admissionRequest: return process_arq(pskb, ct, ctinfo, data, &ras->admissionRequest); case eRasMessage_admissionConfirm: return process_acf(pskb, ct, ctinfo, data, &ras->admissionConfirm); case eRasMessage_locationRequest: return process_lrq(pskb, ct, ctinfo, data, &ras->locationRequest); case eRasMessage_locationConfirm: return process_lcf(pskb, ct, ctinfo, data, &ras->locationConfirm); case eRasMessage_infoRequestResponse: return process_irr(pskb, ct, ctinfo, data, &ras->infoRequestResponse); default: DEBUGP("ip_ct_ras: RAS message %d\n", ras->choice); break; } return 0; } /****************************************************************************/ static int ras_help(struct sk_buff **pskb, struct ip_conntrack *ct, enum ip_conntrack_info ctinfo) { static RasMessage ras; unsigned char *data; int datalen = 0; int ret; DEBUGP("ip_ct_ras: skblen = %u\n", (*pskb)->len); spin_lock_bh(&ip_h323_lock); /* Get UDP data */ data = get_udp_data(pskb, &datalen); if (data == NULL) goto accept; DEBUGP("ip_ct_ras: RAS message %u.%u.%u.%u->%u.%u.%u.%u, len=%d\n", NIPQUAD((*pskb)->nh.iph->saddr), NIPQUAD((*pskb)->nh.iph->daddr), datalen); /* Decode RAS message */ ret = DecodeRasMessage(data, datalen, &ras); if (ret < 0) { if (net_ratelimit()) printk("ip_ct_ras: decoding error: %s\n", ret == H323_ERROR_BOUND ? "out of bound" : "out of range"); goto accept; } /* Process RAS message */ if (process_ras(pskb, ct, ctinfo, &data, &ras) < 0) goto drop; accept: spin_unlock_bh(&ip_h323_lock); return NF_ACCEPT; drop: spin_unlock_bh(&ip_h323_lock); if (net_ratelimit()) printk("ip_ct_ras: packet dropped\n"); return NF_DROP; } /****************************************************************************/ static struct ip_conntrack_helper ip_conntrack_helper_ras = { .name = "RAS", .me = THIS_MODULE, .max_expected = 32, .timeout = 240, .tuple = {.src = {.u = {__constant_htons(RAS_PORT)}}, .dst = {.protonum = IPPROTO_UDP}}, .mask = {.src = {.u = {0xFFFE}}, .dst = {.protonum = 0xFF}}, .help = ras_help, }; /****************************************************************************/ static void ip_conntrack_ras_expect(struct ip_conntrack *new, struct ip_conntrack_expect *this) { write_lock_bh(&ip_conntrack_lock); new->helper = &ip_conntrack_helper_ras; write_unlock_bh(&ip_conntrack_lock); } /****************************************************************************/ /* Not __exit - called from init() */ static void fini(void) { ip_conntrack_helper_unregister(&ip_conntrack_helper_ras); ip_conntrack_helper_unregister(&ip_conntrack_helper_q931); kfree(h323_buffer); DEBUGP("ip_ct_h323: fini\n"); } /****************************************************************************/ static int __init init(void) { int ret; h323_buffer = kmalloc(65536, GFP_KERNEL); if (!h323_buffer) return -ENOMEM; if ((ret = ip_conntrack_helper_register(&ip_conntrack_helper_q931)) || (ret = ip_conntrack_helper_register(&ip_conntrack_helper_ras))) { fini(); return ret; } DEBUGP("ip_ct_h323: init success\n"); return 0; } /****************************************************************************/ module_init(init); module_exit(fini); EXPORT_SYMBOL_GPL(get_h225_addr); EXPORT_SYMBOL_GPL(ip_conntrack_h245_expect); EXPORT_SYMBOL_GPL(ip_conntrack_q931_expect); EXPORT_SYMBOL_GPL(set_h245_addr_hook); EXPORT_SYMBOL_GPL(set_h225_addr_hook); EXPORT_SYMBOL_GPL(set_sig_addr_hook); EXPORT_SYMBOL_GPL(set_ras_addr_hook); EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook); EXPORT_SYMBOL_GPL(nat_t120_hook); EXPORT_SYMBOL_GPL(nat_h245_hook); EXPORT_SYMBOL_GPL(nat_q931_hook); MODULE_AUTHOR("Jing Min Zhao "); MODULE_DESCRIPTION("H.323 connection tracking helper"); MODULE_LICENSE("GPL");