From f587de0e2feb9eb9b94f98d0a7b7437e4d6617b4 Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Sat, 2 Dec 2006 22:08:46 -0800 Subject: [NETFILTER]: nf_conntrack/nf_nat: add H.323 helper port Add IPv4 and IPv6 capable nf_conntrack port of the H.323 conntrack/NAT helper. Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- net/netfilter/nf_conntrack_h323_main.c | 1856 ++++++++++++++++++++++++++++++++ 1 file changed, 1856 insertions(+) create mode 100644 net/netfilter/nf_conntrack_h323_main.c (limited to 'net/netfilter/nf_conntrack_h323_main.c') diff --git a/net/netfilter/nf_conntrack_h323_main.c b/net/netfilter/nf_conntrack_h323_main.c new file mode 100644 index 000000000000..6d8568959f82 --- /dev/null +++ b/net/netfilter/nf_conntrack_h323_main.c @@ -0,0 +1,1856 @@ +/* + * 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 + +#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 __read_mostly = 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 __read_mostly = 1; +module_param(gkrouted_only, int, 0600); +MODULE_PARM_DESC(gkrouted_only, "only accept calls from gatekeeper"); + +static int callforward_filter __read_mostly = 1; +module_param(callforward_filter, bool, 0600); +MODULE_PARM_DESC(callforward_filter, "only create call forwarding expectations " + "if both endpoints are on different sides " + "(determined by routing information)"); + +/* Hooks for NAT */ +int (*set_h245_addr_hook) (struct sk_buff **pskb, + unsigned char **data, int dataoff, + H245_TransportAddress *taddr, + union nf_conntrack_address *addr, __be16 port) + __read_mostly; +int (*set_h225_addr_hook) (struct sk_buff **pskb, + unsigned char **data, int dataoff, + TransportAddress *taddr, + union nf_conntrack_address *addr, __be16 port) + __read_mostly; +int (*set_sig_addr_hook) (struct sk_buff **pskb, + struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, + TransportAddress *taddr, int count) __read_mostly; +int (*set_ras_addr_hook) (struct sk_buff **pskb, + struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, + TransportAddress *taddr, int count) __read_mostly; +int (*nat_rtp_rtcp_hook) (struct sk_buff **pskb, + struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, int dataoff, + H245_TransportAddress *taddr, + __be16 port, __be16 rtp_port, + struct nf_conntrack_expect *rtp_exp, + struct nf_conntrack_expect *rtcp_exp) __read_mostly; +int (*nat_t120_hook) (struct sk_buff **pskb, + struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, int dataoff, + H245_TransportAddress *taddr, __be16 port, + struct nf_conntrack_expect *exp) __read_mostly; +int (*nat_h245_hook) (struct sk_buff **pskb, + struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, int dataoff, + TransportAddress *taddr, __be16 port, + struct nf_conntrack_expect *exp) __read_mostly; +int (*nat_callforwarding_hook) (struct sk_buff **pskb, + struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, int dataoff, + TransportAddress *taddr, __be16 port, + struct nf_conntrack_expect *exp) __read_mostly; +int (*nat_q931_hook) (struct sk_buff **pskb, + struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, TransportAddress *taddr, int idx, + __be16 port, struct nf_conntrack_expect *exp) + __read_mostly; + +static DEFINE_SPINLOCK(nf_h323_lock); +static char *h323_buffer; + +static struct nf_conntrack_helper nf_conntrack_helper_h245; +static struct nf_conntrack_helper nf_conntrack_helper_q931[]; +static struct nf_conntrack_helper nf_conntrack_helper_ras[]; + +/****************************************************************************/ +static int get_tpkt_data(struct sk_buff **pskb, unsigned int protoff, + struct nf_conn *ct, enum ip_conntrack_info ctinfo, + unsigned char **data, int *datalen, int *dataoff) +{ + struct nf_ct_h323_master *info = &nfct_help(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, protoff, sizeof(_tcph), &_tcph); + if (th == NULL) + return 0; + + /* Get TCP data offset */ + tcpdataoff = protoff + 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("nf_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("nf_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("nf_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("nf_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(struct nf_conn *ct, unsigned char *data, + H245_TransportAddress *taddr, + union nf_conntrack_address *addr, __be16 *port) +{ + unsigned char *p; + int family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num; + int len; + + if (taddr->choice != eH245_TransportAddress_unicastAddress) + return 0; + + switch (taddr->unicastAddress.choice) { + case eUnicastAddress_iPAddress: + if (family != AF_INET) + return 0; + p = data + taddr->unicastAddress.iPAddress.network; + len = 4; + break; + case eUnicastAddress_iP6Address: + if (family != AF_INET6) + return 0; + p = data + taddr->unicastAddress.iP6Address.network; + len = 16; + break; + default: + return 0; + } + + memcpy(addr, p, len); + memset((void *)addr + len, 0, sizeof(*addr) - len); + memcpy(port, p + len, sizeof(__be16)); + + return 1; +} + +/****************************************************************************/ +static int expect_rtp_rtcp(struct sk_buff **pskb, struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, int dataoff, + H245_TransportAddress *taddr) +{ + int dir = CTINFO2DIR(ctinfo); + int ret = 0; + __be16 port; + __be16 rtp_port, rtcp_port; + union nf_conntrack_address addr; + struct nf_conntrack_expect *rtp_exp; + struct nf_conntrack_expect *rtcp_exp; + typeof(nat_rtp_rtcp_hook) nat_rtp_rtcp; + + /* Read RTP or RTCP address */ + if (!get_h245_addr(ct, *data, taddr, &addr, &port) || + memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) || + port == 0) + return 0; + + /* RTP port is even */ + port &= htons(~1); + rtp_port = port; + rtcp_port = htons(ntohs(port) + 1); + + /* Create expect for RTP */ + if ((rtp_exp = nf_conntrack_expect_alloc(ct)) == NULL) + return -1; + nf_conntrack_expect_init(rtp_exp, ct->tuplehash[!dir].tuple.src.l3num, + &ct->tuplehash[!dir].tuple.src.u3, + &ct->tuplehash[!dir].tuple.dst.u3, + IPPROTO_UDP, NULL, &rtp_port); + + /* Create expect for RTCP */ + if ((rtcp_exp = nf_conntrack_expect_alloc(ct)) == NULL) { + nf_conntrack_expect_put(rtp_exp); + return -1; + } + nf_conntrack_expect_init(rtcp_exp, ct->tuplehash[!dir].tuple.src.l3num, + &ct->tuplehash[!dir].tuple.src.u3, + &ct->tuplehash[!dir].tuple.dst.u3, + IPPROTO_UDP, NULL, &rtcp_port); + + if (memcmp(&ct->tuplehash[dir].tuple.src.u3, + &ct->tuplehash[!dir].tuple.dst.u3, + sizeof(ct->tuplehash[dir].tuple.src.u3)) && + (nat_rtp_rtcp = rcu_dereference(nat_rtp_rtcp_hook)) && + ct->status & IPS_NAT_MASK) { + /* NAT needed */ + ret = nat_rtp_rtcp(pskb, ct, ctinfo, data, dataoff, + taddr, port, rtp_port, rtp_exp, rtcp_exp); + } else { /* Conntrack only */ + if (nf_conntrack_expect_related(rtp_exp) == 0) { + if (nf_conntrack_expect_related(rtcp_exp) == 0) { + DEBUGP("nf_ct_h323: expect RTP "); + NF_CT_DUMP_TUPLE(&rtp_exp->tuple); + DEBUGP("nf_ct_h323: expect RTCP "); + NF_CT_DUMP_TUPLE(&rtcp_exp->tuple); + } else { + nf_conntrack_unexpect_related(rtp_exp); + ret = -1; + } + } else + ret = -1; + } + + nf_conntrack_expect_put(rtp_exp); + nf_conntrack_expect_put(rtcp_exp); + + return ret; +} + +/****************************************************************************/ +static int expect_t120(struct sk_buff **pskb, + struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, int dataoff, + H245_TransportAddress *taddr) +{ + int dir = CTINFO2DIR(ctinfo); + int ret = 0; + __be16 port; + union nf_conntrack_address addr; + struct nf_conntrack_expect *exp; + typeof(nat_t120_hook) nat_t120; + + /* Read T.120 address */ + if (!get_h245_addr(ct, *data, taddr, &addr, &port) || + memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) || + port == 0) + return 0; + + /* Create expect for T.120 connections */ + if ((exp = nf_conntrack_expect_alloc(ct)) == NULL) + return -1; + nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num, + &ct->tuplehash[!dir].tuple.src.u3, + &ct->tuplehash[!dir].tuple.dst.u3, + IPPROTO_TCP, NULL, &port); + exp->flags = NF_CT_EXPECT_PERMANENT; /* Accept multiple channels */ + + if (memcmp(&ct->tuplehash[dir].tuple.src.u3, + &ct->tuplehash[!dir].tuple.dst.u3, + sizeof(ct->tuplehash[dir].tuple.src.u3)) && + (nat_t120 = rcu_dereference(nat_t120_hook)) && + ct->status & IPS_NAT_MASK) { + /* NAT needed */ + ret = nat_t120(pskb, ct, ctinfo, data, dataoff, taddr, + port, exp); + } else { /* Conntrack only */ + if (nf_conntrack_expect_related(exp) == 0) { + DEBUGP("nf_ct_h323: expect T.120 "); + NF_CT_DUMP_TUPLE(&exp->tuple); + } else + ret = -1; + } + + nf_conntrack_expect_put(exp); + + return ret; +} + +/****************************************************************************/ +static int process_h245_channel(struct sk_buff **pskb, + struct nf_conn *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 nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, int dataoff, + OpenLogicalChannel *olc) +{ + int ret; + + DEBUGP("nf_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 nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, int dataoff, + OpenLogicalChannelAck *olca) +{ + H2250LogicalChannelAckParameters *ack; + int ret; + + DEBUGP("nf_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 nf_conn *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("nf_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("nf_ct_h323: H.245 Response %d\n", + mscm->response.choice); + break; + default: + DEBUGP("nf_ct_h323: H.245 signal %d\n", mscm->choice); + break; + } + + return 0; +} + +/****************************************************************************/ +static int h245_help(struct sk_buff **pskb, unsigned int protoff, + struct nf_conn *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("nf_ct_h245: skblen = %u\n", (*pskb)->len); + + spin_lock_bh(&nf_h323_lock); + + /* Process each TPKT */ + while (get_tpkt_data(pskb, protoff, ct, ctinfo, + &data, &datalen, &dataoff)) { + DEBUGP("nf_ct_h245: TPKT len=%d ", datalen); + NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple); + + /* Decode H.245 signal */ + ret = DecodeMultimediaSystemControlMessage(data, datalen, + &mscm); + if (ret < 0) { + if (net_ratelimit()) + printk("nf_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(&nf_h323_lock); + return NF_ACCEPT; + + drop: + spin_unlock_bh(&nf_h323_lock); + if (net_ratelimit()) + printk("nf_ct_h245: packet dropped\n"); + return NF_DROP; +} + +/****************************************************************************/ +static struct nf_conntrack_helper nf_conntrack_helper_h245 __read_mostly = { + .name = "H.245", + .me = THIS_MODULE, + .max_expected = H323_RTP_CHANNEL_MAX * 4 + 2 /* T.120 */, + .timeout = 240, + .tuple.dst.protonum = IPPROTO_UDP, + .mask.src.u.udp.port = __constant_htons(0xFFFF), + .mask.dst.protonum = 0xFF, + .help = h245_help +}; + +/****************************************************************************/ +int get_h225_addr(struct nf_conn *ct, unsigned char *data, + TransportAddress *taddr, + union nf_conntrack_address *addr, __be16 *port) +{ + unsigned char *p; + int family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num; + int len; + + switch (taddr->choice) { + case eTransportAddress_ipAddress: + if (family != AF_INET) + return 0; + p = data + taddr->ipAddress.ip; + len = 4; + break; + case eTransportAddress_ip6Address: + if (family != AF_INET6) + return 0; + p = data + taddr->ip6Address.ip6; + len = 16; + break; + default: + return 0; + } + + memcpy(addr, p, len); + memset((void *)addr + len, 0, sizeof(*addr) - len); + memcpy(port, p + len, sizeof(__be16)); + + return 1; +} + +/****************************************************************************/ +static int expect_h245(struct sk_buff **pskb, struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, int dataoff, + TransportAddress *taddr) +{ + int dir = CTINFO2DIR(ctinfo); + int ret = 0; + __be16 port; + union nf_conntrack_address addr; + struct nf_conntrack_expect *exp; + typeof(nat_h245_hook) nat_h245; + + /* Read h245Address */ + if (!get_h225_addr(ct, *data, taddr, &addr, &port) || + memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) || + port == 0) + return 0; + + /* Create expect for h245 connection */ + if ((exp = nf_conntrack_expect_alloc(ct)) == NULL) + return -1; + nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num, + &ct->tuplehash[!dir].tuple.src.u3, + &ct->tuplehash[!dir].tuple.dst.u3, + IPPROTO_TCP, NULL, &port); + exp->helper = &nf_conntrack_helper_h245; + + if (memcmp(&ct->tuplehash[dir].tuple.src.u3, + &ct->tuplehash[!dir].tuple.dst.u3, + sizeof(ct->tuplehash[dir].tuple.src.u3)) && + (nat_h245 = rcu_dereference(nat_h245_hook)) && + ct->status & IPS_NAT_MASK) { + /* NAT needed */ + ret = nat_h245(pskb, ct, ctinfo, data, dataoff, taddr, + port, exp); + } else { /* Conntrack only */ + if (nf_conntrack_expect_related(exp) == 0) { + DEBUGP("nf_ct_q931: expect H.245 "); + NF_CT_DUMP_TUPLE(&exp->tuple); + } else + ret = -1; + } + + nf_conntrack_expect_put(exp); + + return ret; +} + +/* If the calling party is on the same side of the forward-to party, + * we don't need to track the second call */ +static int callforward_do_filter(union nf_conntrack_address *src, + union nf_conntrack_address *dst, + int family) +{ + struct flowi fl1, fl2; + int ret = 0; + + memset(&fl1, 0, sizeof(fl1)); + memset(&fl2, 0, sizeof(fl2)); + + switch (family) { + case AF_INET: { + struct rtable *rt1, *rt2; + + fl1.fl4_dst = src->ip; + fl2.fl4_dst = dst->ip; + if (ip_route_output_key(&rt1, &fl1) == 0) { + if (ip_route_output_key(&rt2, &fl2) == 0) { + if (rt1->rt_gateway == rt2->rt_gateway && + rt1->u.dst.dev == rt2->u.dst.dev) + ret = 1; + dst_release(&rt2->u.dst); + } + dst_release(&rt1->u.dst); + } + break; + } +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) + case AF_INET6: { + struct rt6_info *rt1, *rt2; + + memcpy(&fl1.fl6_dst, src, sizeof(fl1.fl6_dst)); + memcpy(&fl2.fl6_dst, dst, sizeof(fl2.fl6_dst)); + rt1 = (struct rt6_info *)ip6_route_output(NULL, &fl1); + if (rt1) { + rt2 = (struct rt6_info *)ip6_route_output(NULL, &fl2); + if (rt2) { + if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway, + sizeof(rt1->rt6i_gateway)) && + rt1->u.dst.dev == rt2->u.dst.dev) + ret = 1; + dst_release(&rt2->u.dst); + } + dst_release(&rt1->u.dst); + } + break; + } +#endif + } + return ret; + +} + +/****************************************************************************/ +static int expect_callforwarding(struct sk_buff **pskb, + struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, int dataoff, + TransportAddress *taddr) +{ + int dir = CTINFO2DIR(ctinfo); + int ret = 0; + __be16 port; + union nf_conntrack_address addr; + struct nf_conntrack_expect *exp; + typeof(nat_callforwarding_hook) nat_callforwarding; + + /* Read alternativeAddress */ + if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0) + return 0; + + /* If the calling party is on the same side of the forward-to party, + * we don't need to track the second call */ + if (callforward_filter && + callforward_do_filter(&addr, &ct->tuplehash[!dir].tuple.src.u3, + ct->tuplehash[!dir].tuple.src.l3num)) { + DEBUGP("nf_ct_q931: Call Forwarding not tracked\n"); + return 0; + } + + /* Create expect for the second call leg */ + if ((exp = nf_conntrack_expect_alloc(ct)) == NULL) + return -1; + nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num, + &ct->tuplehash[!dir].tuple.src.u3, &addr, + IPPROTO_TCP, NULL, &port); + exp->helper = nf_conntrack_helper_q931; + + if (memcmp(&ct->tuplehash[dir].tuple.src.u3, + &ct->tuplehash[!dir].tuple.dst.u3, + sizeof(ct->tuplehash[dir].tuple.src.u3)) && + (nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) && + ct->status & IPS_NAT_MASK) { + /* Need NAT */ + ret = nat_callforwarding(pskb, ct, ctinfo, data, dataoff, + taddr, port, exp); + } else { /* Conntrack only */ + if (nf_conntrack_expect_related(exp) == 0) { + DEBUGP("nf_ct_q931: expect Call Forwarding "); + NF_CT_DUMP_TUPLE(&exp->tuple); + } else + ret = -1; + } + + nf_conntrack_expect_put(exp); + + return ret; +} + +/****************************************************************************/ +static int process_setup(struct sk_buff **pskb, struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, int dataoff, + Setup_UUIE *setup) +{ + int dir = CTINFO2DIR(ctinfo); + int ret; + int i; + __be16 port; + union nf_conntrack_address addr; + typeof(set_h225_addr_hook) set_h225_addr; + + DEBUGP("nf_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; + } + + set_h225_addr = rcu_dereference(set_h225_addr_hook); + if ((setup->options & eSetup_UUIE_destCallSignalAddress) && + (set_h225_addr) && ct->status && IPS_NAT_MASK && + get_h225_addr(ct, *data, &setup->destCallSignalAddress, + &addr, &port) && + memcmp(&addr, &ct->tuplehash[!dir].tuple.src.u3, sizeof(addr))) { + DEBUGP("nf_ct_q931: set destCallSignalAddress " + NIP6_FMT ":%hu->" NIP6_FMT ":%hu\n", + NIP6(*(struct in6_addr *)&addr), ntohs(port), + NIP6(*(struct in6_addr *)&ct->tuplehash[!dir].tuple.src.u3), + ntohs(ct->tuplehash[!dir].tuple.src.u.tcp.port)); + ret = set_h225_addr(pskb, data, dataoff, + &setup->destCallSignalAddress, + &ct->tuplehash[!dir].tuple.src.u3, + ct->tuplehash[!dir].tuple.src.u.tcp.port); + if (ret < 0) + return -1; + } + + if ((setup->options & eSetup_UUIE_sourceCallSignalAddress) && + (set_h225_addr) && ct->status & IPS_NAT_MASK && + get_h225_addr(ct, *data, &setup->sourceCallSignalAddress, + &addr, &port) && + memcmp(&addr, &ct->tuplehash[!dir].tuple.dst.u3, sizeof(addr))) { + DEBUGP("nf_ct_q931: set sourceCallSignalAddress " + NIP6_FMT ":%hu->" NIP6_FMT ":%hu\n", + NIP6(*(struct in6_addr *)&addr), ntohs(port), + NIP6(*(struct in6_addr *)&ct->tuplehash[!dir].tuple.dst.u3), + ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port)); + ret = set_h225_addr(pskb, data, dataoff, + &setup->sourceCallSignalAddress, + &ct->tuplehash[!dir].tuple.dst.u3, + 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 nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, int dataoff, + CallProceeding_UUIE *callproc) +{ + int ret; + int i; + + DEBUGP("nf_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 nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, int dataoff, + Connect_UUIE *connect) +{ + int ret; + int i; + + DEBUGP("nf_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 nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, int dataoff, + Alerting_UUIE *alert) +{ + int ret; + int i; + + DEBUGP("nf_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 nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, int dataoff, + Information_UUIE *info) +{ + int ret; + int i; + + DEBUGP("nf_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 nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, int dataoff, + Facility_UUIE *facility) +{ + int ret; + int i; + + DEBUGP("nf_ct_q931: Facility\n"); + + if (facility->reason.choice == eFacilityReason_callForwarded) { + if (facility->options & eFacility_UUIE_alternativeAddress) + return expect_callforwarding(pskb, ct, ctinfo, data, + dataoff, + &facility-> + alternativeAddress); + return 0; + } + + 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 nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, int dataoff, + Progress_UUIE *progress) +{ + int ret; + int i; + + DEBUGP("nf_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 nf_conn *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("nf_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, unsigned int protoff, + struct nf_conn *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("nf_ct_q931: skblen = %u\n", (*pskb)->len); + + spin_lock_bh(&nf_h323_lock); + + /* Process each TPKT */ + while (get_tpkt_data(pskb, protoff, ct, ctinfo, + &data, &datalen, &dataoff)) { + DEBUGP("nf_ct_q931: TPKT len=%d ", datalen); + NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple); + + /* Decode Q.931 signal */ + ret = DecodeQ931(data, datalen, &q931); + if (ret < 0) { + if (net_ratelimit()) + printk("nf_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(&nf_h323_lock); + return NF_ACCEPT; + + drop: + spin_unlock_bh(&nf_h323_lock); + if (net_ratelimit()) + printk("nf_ct_q931: packet dropped\n"); + return NF_DROP; +} + +/****************************************************************************/ +static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = { + { + .name = "Q.931", + .me = THIS_MODULE, + /* T.120 and H.245 */ + .max_expected = H323_RTP_CHANNEL_MAX * 4 + 4, + .timeout = 240, + .tuple.src.l3num = AF_INET, + .tuple.src.u.tcp.port = __constant_htons(Q931_PORT), + .tuple.dst.protonum = IPPROTO_TCP, + .mask.src.l3num = 0xFFFF, + .mask.src.u.tcp.port = __constant_htons(0xFFFF), + .mask.dst.protonum = 0xFF, + .help = q931_help + }, + { + .name = "Q.931", + .me = THIS_MODULE, + /* T.120 and H.245 */ + .max_expected = H323_RTP_CHANNEL_MAX * 4 + 4, + .timeout = 240, + .tuple.src.l3num = AF_INET6, + .tuple.src.u.tcp.port = __constant_htons(Q931_PORT), + .tuple.dst.protonum = IPPROTO_TCP, + .mask.src.l3num = 0xFFFF, + .mask.src.u.tcp.port = __constant_htons(0xFFFF), + .mask.dst.protonum = 0xFF, + .help = q931_help + }, +}; + +/****************************************************************************/ +static unsigned char *get_udp_data(struct sk_buff **pskb, unsigned int protoff, + int *datalen) +{ + struct udphdr _uh, *uh; + int dataoff; + + uh = skb_header_pointer(*pskb, protoff, sizeof(_uh), &_uh); + if (uh == NULL) + return NULL; + dataoff = protoff + sizeof(_uh); + if (dataoff >= (*pskb)->len) + return NULL; + *datalen = (*pskb)->len - dataoff; + return skb_header_pointer(*pskb, dataoff, *datalen, h323_buffer); +} + +/****************************************************************************/ +static struct nf_conntrack_expect *find_expect(struct nf_conn *ct, + union nf_conntrack_address *addr, + __be16 port) +{ + struct nf_conntrack_expect *exp; + struct nf_conntrack_tuple tuple; + + memset(&tuple.src.u3, 0, sizeof(tuple.src.u3)); + tuple.src.u.tcp.port = 0; + memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3)); + tuple.dst.u.tcp.port = port; + tuple.dst.protonum = IPPROTO_TCP; + + exp = __nf_conntrack_expect_find(&tuple); + if (exp && exp->master == ct) + return exp; + return NULL; +} + +/****************************************************************************/ +static int set_expect_timeout(struct nf_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 nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, + TransportAddress *taddr, int count) +{ + struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info; + int dir = CTINFO2DIR(ctinfo); + int ret = 0; + int i; + __be16 port; + union nf_conntrack_address addr; + struct nf_conntrack_expect *exp; + typeof(nat_q931_hook) nat_q931; + + /* Look for the first related address */ + for (i = 0; i < count; i++) { + if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) && + memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, + sizeof(addr)) == 0 && port != 0) + break; + } + + if (i >= count) /* Not found */ + return 0; + + /* Create expect for Q.931 */ + if ((exp = nf_conntrack_expect_alloc(ct)) == NULL) + return -1; + nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num, + gkrouted_only ? /* only accept calls from GK? */ + &ct->tuplehash[!dir].tuple.src.u3 : + NULL, + &ct->tuplehash[!dir].tuple.dst.u3, + IPPROTO_TCP, NULL, &port); + exp->helper = nf_conntrack_helper_q931; + exp->flags = NF_CT_EXPECT_PERMANENT; /* Accept multiple calls */ + + nat_q931 = rcu_dereference(nat_q931_hook); + if (nat_q931 && ct->status & IPS_NAT_MASK) { /* Need NAT */ + ret = nat_q931(pskb, ct, ctinfo, data, taddr, i, port, exp); + } else { /* Conntrack only */ + if (nf_conntrack_expect_related(exp) == 0) { + DEBUGP("nf_ct_ras: expect Q.931 "); + NF_CT_DUMP_TUPLE(&exp->tuple); + + /* Save port for looking up expect in processing RCF */ + info->sig_port[dir] = port; + } else + ret = -1; + } + + nf_conntrack_expect_put(exp); + + return ret; +} + +/****************************************************************************/ +static int process_grq(struct sk_buff **pskb, struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, GatekeeperRequest *grq) +{ + typeof(set_ras_addr_hook) set_ras_addr; + + DEBUGP("nf_ct_ras: GRQ\n"); + + set_ras_addr = rcu_dereference(set_ras_addr_hook); + if (set_ras_addr && ct->status & IPS_NAT_MASK) /* NATed */ + return set_ras_addr(pskb, ct, ctinfo, data, + &grq->rasAddress, 1); + return 0; +} + +/****************************************************************************/ +static int process_gcf(struct sk_buff **pskb, struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, GatekeeperConfirm *gcf) +{ + int dir = CTINFO2DIR(ctinfo); + int ret = 0; + __be16 port; + union nf_conntrack_address addr; + struct nf_conntrack_expect *exp; + + DEBUGP("nf_ct_ras: GCF\n"); + + if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port)) + return 0; + + /* Registration port is the same as discovery port */ + if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) && + port == 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 = nf_conntrack_expect_alloc(ct)) == NULL) + return -1; + nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num, + &ct->tuplehash[!dir].tuple.src.u3, &addr, + IPPROTO_UDP, NULL, &port); + exp->helper = nf_conntrack_helper_ras; + + if (nf_conntrack_expect_related(exp) == 0) { + DEBUGP("nf_ct_ras: expect RAS "); + NF_CT_DUMP_TUPLE(&exp->tuple); + } else + ret = -1; + + nf_conntrack_expect_put(exp); + + return ret; +} + +/****************************************************************************/ +static int process_rrq(struct sk_buff **pskb, struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, RegistrationRequest *rrq) +{ + struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info; + int ret; + typeof(set_ras_addr_hook) set_ras_addr; + + DEBUGP("nf_ct_ras: RRQ\n"); + + ret = expect_q931(pskb, ct, ctinfo, data, + rrq->callSignalAddress.item, + rrq->callSignalAddress.count); + if (ret < 0) + return -1; + + set_ras_addr = rcu_dereference(set_ras_addr_hook); + if (set_ras_addr && ct->status & IPS_NAT_MASK) { + ret = set_ras_addr(pskb, ct, ctinfo, data, + rrq->rasAddress.item, + rrq->rasAddress.count); + if (ret < 0) + return -1; + } + + if (rrq->options & eRegistrationRequest_timeToLive) { + DEBUGP("nf_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 nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, RegistrationConfirm *rcf) +{ + struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info; + int dir = CTINFO2DIR(ctinfo); + int ret; + struct nf_conntrack_expect *exp; + typeof(set_sig_addr_hook) set_sig_addr; + + DEBUGP("nf_ct_ras: RCF\n"); + + set_sig_addr = rcu_dereference(set_sig_addr_hook); + if (set_sig_addr && ct->status & IPS_NAT_MASK) { + ret = set_sig_addr(pskb, ct, ctinfo, data, + rcf->callSignalAddress.item, + rcf->callSignalAddress.count); + if (ret < 0) + return -1; + } + + if (rcf->options & eRegistrationConfirm_timeToLive) { + DEBUGP("nf_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive); + info->timeout = rcf->timeToLive; + } + + if (info->timeout > 0) { + DEBUGP + ("nf_ct_ras: set RAS connection timeout to %u seconds\n", + info->timeout); + nf_ct_refresh(ct, *pskb, info->timeout * HZ); + + /* Set expect timeout */ + read_lock_bh(&nf_conntrack_lock); + exp = find_expect(ct, &ct->tuplehash[dir].tuple.dst.u3, + info->sig_port[!dir]); + if (exp) { + DEBUGP("nf_ct_ras: set Q.931 expect " + "timeout to %u seconds for", + info->timeout); + NF_CT_DUMP_TUPLE(&exp->tuple); + set_expect_timeout(exp, info->timeout); + } + read_unlock_bh(&nf_conntrack_lock); + } + + return 0; +} + +/****************************************************************************/ +static int process_urq(struct sk_buff **pskb, struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, UnregistrationRequest *urq) +{ + struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info; + int dir = CTINFO2DIR(ctinfo); + int ret; + typeof(set_sig_addr_hook) set_sig_addr; + + DEBUGP("nf_ct_ras: URQ\n"); + + set_sig_addr = rcu_dereference(set_sig_addr_hook); + if (set_sig_addr && ct->status & IPS_NAT_MASK) { + ret = set_sig_addr(pskb, ct, ctinfo, data, + urq->callSignalAddress.item, + urq->callSignalAddress.count); + if (ret < 0) + return -1; + } + + /* Clear old expect */ + nf_ct_remove_expectations(ct); + info->sig_port[dir] = 0; + info->sig_port[!dir] = 0; + + /* Give it 30 seconds for UCF or URJ */ + nf_ct_refresh(ct, *pskb, 30 * HZ); + + return 0; +} + +/****************************************************************************/ +static int process_arq(struct sk_buff **pskb, struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, AdmissionRequest *arq) +{ + struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info; + int dir = CTINFO2DIR(ctinfo); + __be16 port; + union nf_conntrack_address addr; + typeof(set_h225_addr_hook) set_h225_addr; + + DEBUGP("nf_ct_ras: ARQ\n"); + + set_h225_addr = rcu_dereference(set_h225_addr_hook); + if ((arq->options & eAdmissionRequest_destCallSignalAddress) && + get_h225_addr(ct, *data, &arq->destCallSignalAddress, + &addr, &port) && + !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) && + port == info->sig_port[dir] && + set_h225_addr && ct->status & IPS_NAT_MASK) { + /* Answering ARQ */ + return set_h225_addr(pskb, data, 0, + &arq->destCallSignalAddress, + &ct->tuplehash[!dir].tuple.dst.u3, + info->sig_port[!dir]); + } + + if ((arq->options & eAdmissionRequest_srcCallSignalAddress) && + get_h225_addr(ct, *data, &arq->srcCallSignalAddress, + &addr, &port) && + !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) && + set_h225_addr && ct->status & IPS_NAT_MASK) { + /* Calling ARQ */ + return set_h225_addr(pskb, data, 0, + &arq->srcCallSignalAddress, + &ct->tuplehash[!dir].tuple.dst.u3, + port); + } + + return 0; +} + +/****************************************************************************/ +static int process_acf(struct sk_buff **pskb, struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, AdmissionConfirm *acf) +{ + int dir = CTINFO2DIR(ctinfo); + int ret = 0; + __be16 port; + union nf_conntrack_address addr; + struct nf_conntrack_expect *exp; + typeof(set_sig_addr_hook) set_sig_addr; + + DEBUGP("nf_ct_ras: ACF\n"); + + if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress, + &addr, &port)) + return 0; + + if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) { + /* Answering ACF */ + set_sig_addr = rcu_dereference(set_sig_addr_hook); + if (set_sig_addr && ct->status & IPS_NAT_MASK) + return set_sig_addr(pskb, ct, ctinfo, data, + &acf->destCallSignalAddress, 1); + return 0; + } + + /* Need new expect */ + if ((exp = nf_conntrack_expect_alloc(ct)) == NULL) + return -1; + nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num, + &ct->tuplehash[!dir].tuple.src.u3, &addr, + IPPROTO_TCP, NULL, &port); + exp->flags = NF_CT_EXPECT_PERMANENT; + exp->helper = nf_conntrack_helper_q931; + + if (nf_conntrack_expect_related(exp) == 0) { + DEBUGP("nf_ct_ras: expect Q.931 "); + NF_CT_DUMP_TUPLE(&exp->tuple); + } else + ret = -1; + + nf_conntrack_expect_put(exp); + + return ret; +} + +/****************************************************************************/ +static int process_lrq(struct sk_buff **pskb, struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, LocationRequest *lrq) +{ + typeof(set_ras_addr_hook) set_ras_addr; + + DEBUGP("nf_ct_ras: LRQ\n"); + + set_ras_addr = rcu_dereference(set_ras_addr_hook); + if (set_ras_addr && ct->status & IPS_NAT_MASK) + return set_ras_addr(pskb, ct, ctinfo, data, + &lrq->replyAddress, 1); + return 0; +} + +/****************************************************************************/ +static int process_lcf(struct sk_buff **pskb, struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, LocationConfirm *lcf) +{ + int dir = CTINFO2DIR(ctinfo); + int ret = 0; + __be16 port; + union nf_conntrack_address addr; + struct nf_conntrack_expect *exp; + + DEBUGP("nf_ct_ras: LCF\n"); + + if (!get_h225_addr(ct, *data, &lcf->callSignalAddress, + &addr, &port)) + return 0; + + /* Need new expect for call signal */ + if ((exp = nf_conntrack_expect_alloc(ct)) == NULL) + return -1; + nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num, + &ct->tuplehash[!dir].tuple.src.u3, &addr, + IPPROTO_TCP, NULL, &port); + exp->flags = NF_CT_EXPECT_PERMANENT; + exp->helper = nf_conntrack_helper_q931; + + if (nf_conntrack_expect_related(exp) == 0) { + DEBUGP("nf_ct_ras: expect Q.931 "); + NF_CT_DUMP_TUPLE(&exp->tuple); + } else + ret = -1; + + nf_conntrack_expect_put(exp); + + /* Ignore rasAddress */ + + return ret; +} + +/****************************************************************************/ +static int process_irr(struct sk_buff **pskb, struct nf_conn *ct, + enum ip_conntrack_info ctinfo, + unsigned char **data, InfoRequestResponse *irr) +{ + int ret; + typeof(set_ras_addr_hook) set_ras_addr; + typeof(set_sig_addr_hook) set_sig_addr; + + DEBUGP("nf_ct_ras: IRR\n"); + + set_ras_addr = rcu_dereference(set_ras_addr_hook); + if (set_ras_addr && ct->status & IPS_NAT_MASK) { + ret = set_ras_addr(pskb, ct, ctinfo, data, + &irr->rasAddress, 1); + if (ret < 0) + return -1; + } + + set_sig_addr = rcu_dereference(set_sig_addr_hook); + if (set_sig_addr && ct->status & IPS_NAT_MASK) { + ret = set_sig_addr(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 nf_conn *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("nf_ct_ras: RAS message %d\n", ras->choice); + break; + } + + return 0; +} + +/****************************************************************************/ +static int ras_help(struct sk_buff **pskb, unsigned int protoff, + struct nf_conn *ct, enum ip_conntrack_info ctinfo) +{ + static RasMessage ras; + unsigned char *data; + int datalen = 0; + int ret; + + DEBUGP("nf_ct_ras: skblen = %u\n", (*pskb)->len); + + spin_lock_bh(&nf_h323_lock); + + /* Get UDP data */ + data = get_udp_data(pskb, protoff, &datalen); + if (data == NULL) + goto accept; + DEBUGP("nf_ct_ras: RAS message len=%d ", datalen); + NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple); + + /* Decode RAS message */ + ret = DecodeRasMessage(data, datalen, &ras); + if (ret < 0) { + if (net_ratelimit()) + printk("nf_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(&nf_h323_lock); + return NF_ACCEPT; + + drop: + spin_unlock_bh(&nf_h323_lock); + if (net_ratelimit()) + printk("nf_ct_ras: packet dropped\n"); + return NF_DROP; +} + +/****************************************************************************/ +static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = { + { + .name = "RAS", + .me = THIS_MODULE, + .max_expected = 32, + .timeout = 240, + .tuple.src.l3num = AF_INET, + .tuple.src.u.udp.port = __constant_htons(RAS_PORT), + .tuple.dst.protonum = IPPROTO_UDP, + .mask.src.l3num = 0xFFFF, + .mask.src.u.udp.port = __constant_htons(0xFFFF), + .mask.dst.protonum = 0xFF, + .help = ras_help, + }, + { + .name = "RAS", + .me = THIS_MODULE, + .max_expected = 32, + .timeout = 240, + .tuple.src.l3num = AF_INET6, + .tuple.src.u.udp.port = __constant_htons(RAS_PORT), + .tuple.dst.protonum = IPPROTO_UDP, + .mask.src.l3num = 0xFFFF, + .mask.src.u.udp.port = __constant_htons(0xFFFF), + .mask.dst.protonum = 0xFF, + .help = ras_help, + }, +}; + +/****************************************************************************/ +static void __exit nf_conntrack_h323_fini(void) +{ + nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[1]); + nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]); + nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]); + nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]); + kfree(h323_buffer); + DEBUGP("nf_ct_h323: fini\n"); +} + +/****************************************************************************/ +static int __init nf_conntrack_h323_init(void) +{ + int ret; + + h323_buffer = kmalloc(65536, GFP_KERNEL); + if (!h323_buffer) + return -ENOMEM; + ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[0]); + if (ret < 0) + goto err1; + ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[1]); + if (ret < 0) + goto err2; + ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[0]); + if (ret < 0) + goto err3; + ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[1]); + if (ret < 0) + goto err4; + DEBUGP("nf_ct_h323: init success\n"); + return 0; + +err4: + nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]); +err3: + nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]); +err2: + nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]); +err1: + return ret; +} + +/****************************************************************************/ +module_init(nf_conntrack_h323_init); +module_exit(nf_conntrack_h323_fini); + +EXPORT_SYMBOL_GPL(get_h225_addr); +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_callforwarding_hook); +EXPORT_SYMBOL_GPL(nat_q931_hook); + +MODULE_AUTHOR("Jing Min Zhao "); +MODULE_DESCRIPTION("H.323 connection tracking helper"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("ip_conntrack_h323"); 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