diff options
author | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-04-27 09:26:46 -0700 |
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committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-04-27 09:26:46 -0700 |
commit | 15c54033964a943de7b0763efd3bd0ede7326395 (patch) | |
tree | 840b292612d1b5396d5bab5bde537a9013db3ceb /net/ipv4/netfilter/ip_conntrack_helper_pptp.c | |
parent | ad5da3cf39a5b11a198929be1f2644e17ecd767e (diff) | |
parent | 912a41a4ab935ce8c4308428ec13fc7f8b1f18f4 (diff) |
Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6: (448 commits)
[IPV4] nl_fib_lookup: Initialise res.r before fib_res_put(&res)
[IPV6]: Fix thinko in ipv6_rthdr_rcv() changes.
[IPV4]: Add multipath cached to feature-removal-schedule.txt
[WIRELESS] cfg80211: Clarify locking comment.
[WIRELESS] cfg80211: Fix locking in wiphy_new.
[WEXT] net_device: Don't include wext bits if not required.
[WEXT]: Misc code cleanups.
[WEXT]: Reduce inline abuse.
[WEXT]: Move EXPORT_SYMBOL statements where they belong.
[WEXT]: Cleanup early ioctl call path.
[WEXT]: Remove options.
[WEXT]: Remove dead debug code.
[WEXT]: Clean up how wext is called.
[WEXT]: Move to net/wireless
[AFS]: Eliminate cmpxchg() usage in vlocation code.
[RXRPC]: Fix pointers passed to bitops.
[RXRPC]: Remove bogus atomic_* overrides.
[AFS]: Fix u64 printing in debug logging.
[AFS]: Add "directory write" support.
[AFS]: Implement the CB.InitCallBackState3 operation.
...
Diffstat (limited to 'net/ipv4/netfilter/ip_conntrack_helper_pptp.c')
-rw-r--r-- | net/ipv4/netfilter/ip_conntrack_helper_pptp.c | 684 |
1 files changed, 0 insertions, 684 deletions
diff --git a/net/ipv4/netfilter/ip_conntrack_helper_pptp.c b/net/ipv4/netfilter/ip_conntrack_helper_pptp.c deleted file mode 100644 index 2b760c5cf70..00000000000 --- a/net/ipv4/netfilter/ip_conntrack_helper_pptp.c +++ /dev/null @@ -1,684 +0,0 @@ -/* - * ip_conntrack_pptp.c - Version 3.0 - * - * Connection tracking support for PPTP (Point to Point Tunneling Protocol). - * PPTP is a a protocol for creating virtual private networks. - * It is a specification defined by Microsoft and some vendors - * working with Microsoft. PPTP is built on top of a modified - * version of the Internet Generic Routing Encapsulation Protocol. - * GRE is defined in RFC 1701 and RFC 1702. Documentation of - * PPTP can be found in RFC 2637 - * - * (C) 2000-2005 by Harald Welte <laforge@gnumonks.org> - * - * Development of this code funded by Astaro AG (http://www.astaro.com/) - * - * Limitations: - * - We blindly assume that control connections are always - * established in PNS->PAC direction. This is a violation - * of RFFC2673 - * - We can only support one single call within each session - * - * TODO: - * - testing of incoming PPTP calls - * - * Changes: - * 2002-02-05 - Version 1.3 - * - Call ip_conntrack_unexpect_related() from - * pptp_destroy_siblings() to destroy expectations in case - * CALL_DISCONNECT_NOTIFY or tcp fin packet was seen - * (Philip Craig <philipc@snapgear.com>) - * - Add Version information at module loadtime - * 2002-02-10 - Version 1.6 - * - move to C99 style initializers - * - remove second expectation if first arrives - * 2004-10-22 - Version 2.0 - * - merge Mandrake's 2.6.x port with recent 2.6.x API changes - * - fix lots of linear skb assumptions from Mandrake's port - * 2005-06-10 - Version 2.1 - * - use ip_conntrack_expect_free() instead of kfree() on the - * expect's (which are from the slab for quite some time) - * 2005-06-10 - Version 3.0 - * - port helper to post-2.6.11 API changes, - * funded by Oxcoda NetBox Blue (http://www.netboxblue.com/) - * 2005-07-30 - Version 3.1 - * - port helper to 2.6.13 API changes - * - */ - -#include <linux/module.h> -#include <linux/netfilter.h> -#include <linux/ip.h> -#include <net/checksum.h> -#include <net/tcp.h> - -#include <linux/netfilter_ipv4/ip_conntrack.h> -#include <linux/netfilter_ipv4/ip_conntrack_core.h> -#include <linux/netfilter_ipv4/ip_conntrack_helper.h> -#include <linux/netfilter_ipv4/ip_conntrack_proto_gre.h> -#include <linux/netfilter_ipv4/ip_conntrack_pptp.h> - -#define IP_CT_PPTP_VERSION "3.1" - -MODULE_LICENSE("GPL"); -MODULE_AUTHOR("Harald Welte <laforge@gnumonks.org>"); -MODULE_DESCRIPTION("Netfilter connection tracking helper module for PPTP"); - -static DEFINE_SPINLOCK(ip_pptp_lock); - -int -(*ip_nat_pptp_hook_outbound)(struct sk_buff **pskb, - struct ip_conntrack *ct, - enum ip_conntrack_info ctinfo, - struct PptpControlHeader *ctlh, - union pptp_ctrl_union *pptpReq); - -int -(*ip_nat_pptp_hook_inbound)(struct sk_buff **pskb, - struct ip_conntrack *ct, - enum ip_conntrack_info ctinfo, - struct PptpControlHeader *ctlh, - union pptp_ctrl_union *pptpReq); - -void -(*ip_nat_pptp_hook_exp_gre)(struct ip_conntrack_expect *expect_orig, - struct ip_conntrack_expect *expect_reply); - -void -(*ip_nat_pptp_hook_expectfn)(struct ip_conntrack *ct, - struct ip_conntrack_expect *exp); - -#if 0 -/* PptpControlMessageType names */ -const char *pptp_msg_name[] = { - "UNKNOWN_MESSAGE", - "START_SESSION_REQUEST", - "START_SESSION_REPLY", - "STOP_SESSION_REQUEST", - "STOP_SESSION_REPLY", - "ECHO_REQUEST", - "ECHO_REPLY", - "OUT_CALL_REQUEST", - "OUT_CALL_REPLY", - "IN_CALL_REQUEST", - "IN_CALL_REPLY", - "IN_CALL_CONNECT", - "CALL_CLEAR_REQUEST", - "CALL_DISCONNECT_NOTIFY", - "WAN_ERROR_NOTIFY", - "SET_LINK_INFO" -}; -EXPORT_SYMBOL(pptp_msg_name); -#define DEBUGP(format, args...) printk(KERN_DEBUG "%s:%s: " format, __FILE__, __FUNCTION__, ## args) -#else -#define DEBUGP(format, args...) -#endif - -#define SECS *HZ -#define MINS * 60 SECS -#define HOURS * 60 MINS - -#define PPTP_GRE_TIMEOUT (10 MINS) -#define PPTP_GRE_STREAM_TIMEOUT (5 HOURS) - -static void pptp_expectfn(struct ip_conntrack *ct, - struct ip_conntrack_expect *exp) -{ - typeof(ip_nat_pptp_hook_expectfn) ip_nat_pptp_expectfn; - - DEBUGP("increasing timeouts\n"); - - /* increase timeout of GRE data channel conntrack entry */ - ct->proto.gre.timeout = PPTP_GRE_TIMEOUT; - ct->proto.gre.stream_timeout = PPTP_GRE_STREAM_TIMEOUT; - - /* Can you see how rusty this code is, compared with the pre-2.6.11 - * one? That's what happened to my shiny newnat of 2002 ;( -HW */ - - rcu_read_lock(); - ip_nat_pptp_expectfn = rcu_dereference(ip_nat_pptp_hook_expectfn); - if (!ip_nat_pptp_expectfn) { - struct ip_conntrack_tuple inv_t; - struct ip_conntrack_expect *exp_other; - - /* obviously this tuple inversion only works until you do NAT */ - invert_tuplepr(&inv_t, &exp->tuple); - DEBUGP("trying to unexpect other dir: "); - DUMP_TUPLE(&inv_t); - - exp_other = ip_conntrack_expect_find_get(&inv_t); - if (exp_other) { - /* delete other expectation. */ - DEBUGP("found\n"); - ip_conntrack_unexpect_related(exp_other); - ip_conntrack_expect_put(exp_other); - } else { - DEBUGP("not found\n"); - } - } else { - /* we need more than simple inversion */ - ip_nat_pptp_expectfn(ct, exp); - } - rcu_read_unlock(); -} - -static int destroy_sibling_or_exp(const struct ip_conntrack_tuple *t) -{ - struct ip_conntrack_tuple_hash *h; - struct ip_conntrack_expect *exp; - - DEBUGP("trying to timeout ct or exp for tuple "); - DUMP_TUPLE(t); - - h = ip_conntrack_find_get(t, NULL); - if (h) { - struct ip_conntrack *sibling = tuplehash_to_ctrack(h); - DEBUGP("setting timeout of conntrack %p to 0\n", sibling); - sibling->proto.gre.timeout = 0; - sibling->proto.gre.stream_timeout = 0; - if (del_timer(&sibling->timeout)) - sibling->timeout.function((unsigned long)sibling); - ip_conntrack_put(sibling); - return 1; - } else { - exp = ip_conntrack_expect_find_get(t); - if (exp) { - DEBUGP("unexpect_related of expect %p\n", exp); - ip_conntrack_unexpect_related(exp); - ip_conntrack_expect_put(exp); - return 1; - } - } - - return 0; -} - - -/* timeout GRE data connections */ -static void pptp_destroy_siblings(struct ip_conntrack *ct) -{ - struct ip_conntrack_tuple t; - - ip_ct_gre_keymap_destroy(ct); - /* Since ct->sibling_list has literally rusted away in 2.6.11, - * we now need another way to find out about our sibling - * contrack and expects... -HW */ - - /* try original (pns->pac) tuple */ - memcpy(&t, &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple, sizeof(t)); - t.dst.protonum = IPPROTO_GRE; - t.src.u.gre.key = ct->help.ct_pptp_info.pns_call_id; - t.dst.u.gre.key = ct->help.ct_pptp_info.pac_call_id; - - if (!destroy_sibling_or_exp(&t)) - DEBUGP("failed to timeout original pns->pac ct/exp\n"); - - /* try reply (pac->pns) tuple */ - memcpy(&t, &ct->tuplehash[IP_CT_DIR_REPLY].tuple, sizeof(t)); - t.dst.protonum = IPPROTO_GRE; - t.src.u.gre.key = ct->help.ct_pptp_info.pac_call_id; - t.dst.u.gre.key = ct->help.ct_pptp_info.pns_call_id; - - if (!destroy_sibling_or_exp(&t)) - DEBUGP("failed to timeout reply pac->pns ct/exp\n"); -} - -/* expect GRE connections (PNS->PAC and PAC->PNS direction) */ -static inline int -exp_gre(struct ip_conntrack *ct, - __be16 callid, - __be16 peer_callid) -{ - struct ip_conntrack_expect *exp_orig, *exp_reply; - int ret = 1; - typeof(ip_nat_pptp_hook_exp_gre) ip_nat_pptp_exp_gre; - - exp_orig = ip_conntrack_expect_alloc(ct); - if (exp_orig == NULL) - goto out; - - exp_reply = ip_conntrack_expect_alloc(ct); - if (exp_reply == NULL) - goto out_put_orig; - - /* original direction, PNS->PAC */ - exp_orig->tuple.src.ip = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip; - exp_orig->tuple.src.u.gre.key = peer_callid; - exp_orig->tuple.dst.ip = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.ip; - exp_orig->tuple.dst.u.gre.key = callid; - exp_orig->tuple.dst.protonum = IPPROTO_GRE; - - exp_orig->mask.src.ip = htonl(0xffffffff); - exp_orig->mask.src.u.all = 0; - exp_orig->mask.dst.u.gre.key = htons(0xffff); - exp_orig->mask.dst.ip = htonl(0xffffffff); - exp_orig->mask.dst.protonum = 0xff; - - exp_orig->master = ct; - exp_orig->expectfn = pptp_expectfn; - exp_orig->flags = 0; - - /* both expectations are identical apart from tuple */ - memcpy(exp_reply, exp_orig, sizeof(*exp_reply)); - - /* reply direction, PAC->PNS */ - exp_reply->tuple.src.ip = ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.ip; - exp_reply->tuple.src.u.gre.key = callid; - exp_reply->tuple.dst.ip = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip; - exp_reply->tuple.dst.u.gre.key = peer_callid; - exp_reply->tuple.dst.protonum = IPPROTO_GRE; - - ip_nat_pptp_exp_gre = rcu_dereference(ip_nat_pptp_hook_exp_gre); - if (ip_nat_pptp_exp_gre) - ip_nat_pptp_exp_gre(exp_orig, exp_reply); - if (ip_conntrack_expect_related(exp_orig) != 0) - goto out_put_both; - if (ip_conntrack_expect_related(exp_reply) != 0) - goto out_unexpect_orig; - - /* Add GRE keymap entries */ - if (ip_ct_gre_keymap_add(ct, &exp_orig->tuple, 0) != 0) - goto out_unexpect_both; - if (ip_ct_gre_keymap_add(ct, &exp_reply->tuple, 1) != 0) { - ip_ct_gre_keymap_destroy(ct); - goto out_unexpect_both; - } - ret = 0; - -out_put_both: - ip_conntrack_expect_put(exp_reply); -out_put_orig: - ip_conntrack_expect_put(exp_orig); -out: - return ret; - -out_unexpect_both: - ip_conntrack_unexpect_related(exp_reply); -out_unexpect_orig: - ip_conntrack_unexpect_related(exp_orig); - goto out_put_both; -} - -static inline int -pptp_inbound_pkt(struct sk_buff **pskb, - struct PptpControlHeader *ctlh, - union pptp_ctrl_union *pptpReq, - unsigned int reqlen, - struct ip_conntrack *ct, - enum ip_conntrack_info ctinfo) -{ - struct ip_ct_pptp_master *info = &ct->help.ct_pptp_info; - u_int16_t msg; - __be16 cid = 0, pcid = 0; - typeof(ip_nat_pptp_hook_inbound) ip_nat_pptp_inbound; - - msg = ntohs(ctlh->messageType); - DEBUGP("inbound control message %s\n", pptp_msg_name[msg]); - - switch (msg) { - case PPTP_START_SESSION_REPLY: - /* server confirms new control session */ - if (info->sstate < PPTP_SESSION_REQUESTED) - goto invalid; - if (pptpReq->srep.resultCode == PPTP_START_OK) - info->sstate = PPTP_SESSION_CONFIRMED; - else - info->sstate = PPTP_SESSION_ERROR; - break; - - case PPTP_STOP_SESSION_REPLY: - /* server confirms end of control session */ - if (info->sstate > PPTP_SESSION_STOPREQ) - goto invalid; - if (pptpReq->strep.resultCode == PPTP_STOP_OK) - info->sstate = PPTP_SESSION_NONE; - else - info->sstate = PPTP_SESSION_ERROR; - break; - - case PPTP_OUT_CALL_REPLY: - /* server accepted call, we now expect GRE frames */ - if (info->sstate != PPTP_SESSION_CONFIRMED) - goto invalid; - if (info->cstate != PPTP_CALL_OUT_REQ && - info->cstate != PPTP_CALL_OUT_CONF) - goto invalid; - - cid = pptpReq->ocack.callID; - pcid = pptpReq->ocack.peersCallID; - if (info->pns_call_id != pcid) - goto invalid; - DEBUGP("%s, CID=%X, PCID=%X\n", pptp_msg_name[msg], - ntohs(cid), ntohs(pcid)); - - if (pptpReq->ocack.resultCode == PPTP_OUTCALL_CONNECT) { - info->cstate = PPTP_CALL_OUT_CONF; - info->pac_call_id = cid; - exp_gre(ct, cid, pcid); - } else - info->cstate = PPTP_CALL_NONE; - break; - - case PPTP_IN_CALL_REQUEST: - /* server tells us about incoming call request */ - if (info->sstate != PPTP_SESSION_CONFIRMED) - goto invalid; - - cid = pptpReq->icreq.callID; - DEBUGP("%s, CID=%X\n", pptp_msg_name[msg], ntohs(cid)); - info->cstate = PPTP_CALL_IN_REQ; - info->pac_call_id = cid; - break; - - case PPTP_IN_CALL_CONNECT: - /* server tells us about incoming call established */ - if (info->sstate != PPTP_SESSION_CONFIRMED) - goto invalid; - if (info->cstate != PPTP_CALL_IN_REP && - info->cstate != PPTP_CALL_IN_CONF) - goto invalid; - - pcid = pptpReq->iccon.peersCallID; - cid = info->pac_call_id; - - if (info->pns_call_id != pcid) - goto invalid; - - DEBUGP("%s, PCID=%X\n", pptp_msg_name[msg], ntohs(pcid)); - info->cstate = PPTP_CALL_IN_CONF; - - /* we expect a GRE connection from PAC to PNS */ - exp_gre(ct, cid, pcid); - break; - - case PPTP_CALL_DISCONNECT_NOTIFY: - /* server confirms disconnect */ - cid = pptpReq->disc.callID; - DEBUGP("%s, CID=%X\n", pptp_msg_name[msg], ntohs(cid)); - info->cstate = PPTP_CALL_NONE; - - /* untrack this call id, unexpect GRE packets */ - pptp_destroy_siblings(ct); - break; - - case PPTP_WAN_ERROR_NOTIFY: - case PPTP_ECHO_REQUEST: - case PPTP_ECHO_REPLY: - /* I don't have to explain these ;) */ - break; - default: - goto invalid; - } - - ip_nat_pptp_inbound = rcu_dereference(ip_nat_pptp_hook_inbound); - if (ip_nat_pptp_inbound) - return ip_nat_pptp_inbound(pskb, ct, ctinfo, ctlh, pptpReq); - return NF_ACCEPT; - -invalid: - DEBUGP("invalid %s: type=%d cid=%u pcid=%u " - "cstate=%d sstate=%d pns_cid=%u pac_cid=%u\n", - msg <= PPTP_MSG_MAX ? pptp_msg_name[msg] : pptp_msg_name[0], - msg, ntohs(cid), ntohs(pcid), info->cstate, info->sstate, - ntohs(info->pns_call_id), ntohs(info->pac_call_id)); - return NF_ACCEPT; -} - -static inline int -pptp_outbound_pkt(struct sk_buff **pskb, - struct PptpControlHeader *ctlh, - union pptp_ctrl_union *pptpReq, - unsigned int reqlen, - struct ip_conntrack *ct, - enum ip_conntrack_info ctinfo) -{ - struct ip_ct_pptp_master *info = &ct->help.ct_pptp_info; - u_int16_t msg; - __be16 cid = 0, pcid = 0; - typeof(ip_nat_pptp_hook_outbound) ip_nat_pptp_outbound; - - msg = ntohs(ctlh->messageType); - DEBUGP("outbound control message %s\n", pptp_msg_name[msg]); - - switch (msg) { - case PPTP_START_SESSION_REQUEST: - /* client requests for new control session */ - if (info->sstate != PPTP_SESSION_NONE) - goto invalid; - info->sstate = PPTP_SESSION_REQUESTED; - break; - case PPTP_STOP_SESSION_REQUEST: - /* client requests end of control session */ - info->sstate = PPTP_SESSION_STOPREQ; - break; - - case PPTP_OUT_CALL_REQUEST: - /* client initiating connection to server */ - if (info->sstate != PPTP_SESSION_CONFIRMED) - goto invalid; - info->cstate = PPTP_CALL_OUT_REQ; - /* track PNS call id */ - cid = pptpReq->ocreq.callID; - DEBUGP("%s, CID=%X\n", pptp_msg_name[msg], ntohs(cid)); - info->pns_call_id = cid; - break; - case PPTP_IN_CALL_REPLY: - /* client answers incoming call */ - if (info->cstate != PPTP_CALL_IN_REQ && - info->cstate != PPTP_CALL_IN_REP) - goto invalid; - - cid = pptpReq->icack.callID; - pcid = pptpReq->icack.peersCallID; - if (info->pac_call_id != pcid) - goto invalid; - DEBUGP("%s, CID=%X PCID=%X\n", pptp_msg_name[msg], - ntohs(cid), ntohs(pcid)); - - if (pptpReq->icack.resultCode == PPTP_INCALL_ACCEPT) { - /* part two of the three-way handshake */ - info->cstate = PPTP_CALL_IN_REP; - info->pns_call_id = cid; - } else - info->cstate = PPTP_CALL_NONE; - break; - - case PPTP_CALL_CLEAR_REQUEST: - /* client requests hangup of call */ - if (info->sstate != PPTP_SESSION_CONFIRMED) - goto invalid; - /* FUTURE: iterate over all calls and check if - * call ID is valid. We don't do this without newnat, - * because we only know about last call */ - info->cstate = PPTP_CALL_CLEAR_REQ; - break; - case PPTP_SET_LINK_INFO: - case PPTP_ECHO_REQUEST: - case PPTP_ECHO_REPLY: - /* I don't have to explain these ;) */ - break; - default: - goto invalid; - } - - ip_nat_pptp_outbound = rcu_dereference(ip_nat_pptp_hook_outbound); - if (ip_nat_pptp_outbound) - return ip_nat_pptp_outbound(pskb, ct, ctinfo, ctlh, pptpReq); - return NF_ACCEPT; - -invalid: - DEBUGP("invalid %s: type=%d cid=%u pcid=%u " - "cstate=%d sstate=%d pns_cid=%u pac_cid=%u\n", - msg <= PPTP_MSG_MAX ? pptp_msg_name[msg] : pptp_msg_name[0], - msg, ntohs(cid), ntohs(pcid), info->cstate, info->sstate, - ntohs(info->pns_call_id), ntohs(info->pac_call_id)); - return NF_ACCEPT; -} - -static const unsigned int pptp_msg_size[] = { - [PPTP_START_SESSION_REQUEST] = sizeof(struct PptpStartSessionRequest), - [PPTP_START_SESSION_REPLY] = sizeof(struct PptpStartSessionReply), - [PPTP_STOP_SESSION_REQUEST] = sizeof(struct PptpStopSessionRequest), - [PPTP_STOP_SESSION_REPLY] = sizeof(struct PptpStopSessionReply), - [PPTP_OUT_CALL_REQUEST] = sizeof(struct PptpOutCallRequest), - [PPTP_OUT_CALL_REPLY] = sizeof(struct PptpOutCallReply), - [PPTP_IN_CALL_REQUEST] = sizeof(struct PptpInCallRequest), - [PPTP_IN_CALL_REPLY] = sizeof(struct PptpInCallReply), - [PPTP_IN_CALL_CONNECT] = sizeof(struct PptpInCallConnected), - [PPTP_CALL_CLEAR_REQUEST] = sizeof(struct PptpClearCallRequest), - [PPTP_CALL_DISCONNECT_NOTIFY] = sizeof(struct PptpCallDisconnectNotify), - [PPTP_WAN_ERROR_NOTIFY] = sizeof(struct PptpWanErrorNotify), - [PPTP_SET_LINK_INFO] = sizeof(struct PptpSetLinkInfo), -}; - -/* track caller id inside control connection, call expect_related */ -static int -conntrack_pptp_help(struct sk_buff **pskb, - struct ip_conntrack *ct, enum ip_conntrack_info ctinfo) - -{ - int dir = CTINFO2DIR(ctinfo); - struct ip_ct_pptp_master *info = &ct->help.ct_pptp_info; - struct tcphdr _tcph, *tcph; - struct pptp_pkt_hdr _pptph, *pptph; - struct PptpControlHeader _ctlh, *ctlh; - union pptp_ctrl_union _pptpReq, *pptpReq; - unsigned int tcplen = (*pskb)->len - (*pskb)->nh.iph->ihl * 4; - unsigned int datalen, reqlen, nexthdr_off; - int oldsstate, oldcstate; - int ret; - u_int16_t msg; - - /* don't do any tracking before tcp handshake complete */ - if (ctinfo != IP_CT_ESTABLISHED - && ctinfo != IP_CT_ESTABLISHED+IP_CT_IS_REPLY) { - DEBUGP("ctinfo = %u, skipping\n", ctinfo); - return NF_ACCEPT; - } - - nexthdr_off = (*pskb)->nh.iph->ihl*4; - tcph = skb_header_pointer(*pskb, nexthdr_off, sizeof(_tcph), &_tcph); - BUG_ON(!tcph); - nexthdr_off += tcph->doff * 4; - datalen = tcplen - tcph->doff * 4; - - pptph = skb_header_pointer(*pskb, nexthdr_off, sizeof(_pptph), &_pptph); - if (!pptph) { - DEBUGP("no full PPTP header, can't track\n"); - return NF_ACCEPT; - } - nexthdr_off += sizeof(_pptph); - datalen -= sizeof(_pptph); - - /* if it's not a control message we can't do anything with it */ - if (ntohs(pptph->packetType) != PPTP_PACKET_CONTROL || - ntohl(pptph->magicCookie) != PPTP_MAGIC_COOKIE) { - DEBUGP("not a control packet\n"); - return NF_ACCEPT; - } - - ctlh = skb_header_pointer(*pskb, nexthdr_off, sizeof(_ctlh), &_ctlh); - if (!ctlh) - return NF_ACCEPT; - nexthdr_off += sizeof(_ctlh); - datalen -= sizeof(_ctlh); - - reqlen = datalen; - msg = ntohs(ctlh->messageType); - if (msg > 0 && msg <= PPTP_MSG_MAX && reqlen < pptp_msg_size[msg]) - return NF_ACCEPT; - if (reqlen > sizeof(*pptpReq)) - reqlen = sizeof(*pptpReq); - - pptpReq = skb_header_pointer(*pskb, nexthdr_off, reqlen, &_pptpReq); - if (!pptpReq) - return NF_ACCEPT; - - oldsstate = info->sstate; - oldcstate = info->cstate; - - spin_lock_bh(&ip_pptp_lock); - - /* FIXME: We just blindly assume that the control connection is always - * established from PNS->PAC. However, RFC makes no guarantee */ - if (dir == IP_CT_DIR_ORIGINAL) - /* client -> server (PNS -> PAC) */ - ret = pptp_outbound_pkt(pskb, ctlh, pptpReq, reqlen, ct, - ctinfo); - else - /* server -> client (PAC -> PNS) */ - ret = pptp_inbound_pkt(pskb, ctlh, pptpReq, reqlen, ct, - ctinfo); - DEBUGP("sstate: %d->%d, cstate: %d->%d\n", - oldsstate, info->sstate, oldcstate, info->cstate); - spin_unlock_bh(&ip_pptp_lock); - - return ret; -} - -/* control protocol helper */ -static struct ip_conntrack_helper pptp = { - .list = { NULL, NULL }, - .name = "pptp", - .me = THIS_MODULE, - .max_expected = 2, - .timeout = 5 * 60, - .tuple = { .src = { .ip = 0, - .u = { .tcp = { .port = - __constant_htons(PPTP_CONTROL_PORT) } } - }, - .dst = { .ip = 0, - .u = { .all = 0 }, - .protonum = IPPROTO_TCP - } - }, - .mask = { .src = { .ip = 0, - .u = { .tcp = { .port = __constant_htons(0xffff) } } - }, - .dst = { .ip = 0, - .u = { .all = 0 }, - .protonum = 0xff - } - }, - .help = conntrack_pptp_help, - .destroy = pptp_destroy_siblings, -}; - -extern void ip_ct_proto_gre_fini(void); -extern int __init ip_ct_proto_gre_init(void); - -/* ip_conntrack_pptp initialization */ -static int __init ip_conntrack_helper_pptp_init(void) -{ - int retcode; - - retcode = ip_ct_proto_gre_init(); - if (retcode < 0) - return retcode; - - DEBUGP(" registering helper\n"); - if ((retcode = ip_conntrack_helper_register(&pptp))) { - printk(KERN_ERR "Unable to register conntrack application " - "helper for pptp: %d\n", retcode); - ip_ct_proto_gre_fini(); - return retcode; - } - - printk("ip_conntrack_pptp version %s loaded\n", IP_CT_PPTP_VERSION); - return 0; -} - -static void __exit ip_conntrack_helper_pptp_fini(void) -{ - ip_conntrack_helper_unregister(&pptp); - ip_ct_proto_gre_fini(); - printk("ip_conntrack_pptp version %s unloaded\n", IP_CT_PPTP_VERSION); -} - -module_init(ip_conntrack_helper_pptp_init); -module_exit(ip_conntrack_helper_pptp_fini); - -EXPORT_SYMBOL(ip_nat_pptp_hook_outbound); -EXPORT_SYMBOL(ip_nat_pptp_hook_inbound); -EXPORT_SYMBOL(ip_nat_pptp_hook_exp_gre); -EXPORT_SYMBOL(ip_nat_pptp_hook_expectfn); |