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Diffstat (limited to 'net/ipv4/netfilter/ip_nat_helper_pptp.c')
-rw-r--r--net/ipv4/netfilter/ip_nat_helper_pptp.c350
1 files changed, 0 insertions, 350 deletions
diff --git a/net/ipv4/netfilter/ip_nat_helper_pptp.c b/net/ipv4/netfilter/ip_nat_helper_pptp.c
deleted file mode 100644
index 24ce4a5023d..00000000000
--- a/net/ipv4/netfilter/ip_nat_helper_pptp.c
+++ /dev/null
@@ -1,350 +0,0 @@
-/*
- * ip_nat_pptp.c - Version 3.0
- *
- * NAT 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/)
- *
- * TODO: - NAT to a unique tuple, not to TCP source port
- * (needs netfilter tuple reservation)
- *
- * Changes:
- * 2002-02-10 - Version 1.3
- * - Use ip_nat_mangle_tcp_packet() because of cloned skb's
- * in local connections (Philip Craig <philipc@snapgear.com>)
- * - add checks for magicCookie and pptp version
- * - make argument list of pptp_{out,in}bound_packet() shorter
- * - move to C99 style initializers
- * - print version number at module loadtime
- * 2003-09-22 - Version 1.5
- * - use SNATed tcp sourceport as callid, since we get called before
- * TCP header is mangled (Philip Craig <philipc@snapgear.com>)
- * 2004-10-22 - Version 2.0
- * - kernel 2.6.x version
- * 2005-06-10 - Version 3.0
- * - kernel >= 2.6.11 version,
- * funded by Oxcoda NetBox Blue (http://www.netboxblue.com/)
- *
- */
-
-#include <linux/module.h>
-#include <linux/ip.h>
-#include <linux/tcp.h>
-#include <net/tcp.h>
-
-#include <linux/netfilter_ipv4/ip_nat.h>
-#include <linux/netfilter_ipv4/ip_nat_rule.h>
-#include <linux/netfilter_ipv4/ip_nat_helper.h>
-#include <linux/netfilter_ipv4/ip_nat_pptp.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_NAT_PPTP_VERSION "3.0"
-
-#define REQ_CID(req, off) (*(__be16 *)((char *)(req) + (off)))
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Harald Welte <laforge@gnumonks.org>");
-MODULE_DESCRIPTION("Netfilter NAT helper module for PPTP");
-
-
-#if 0
-extern const char *pptp_msg_name[];
-#define DEBUGP(format, args...) printk(KERN_DEBUG "%s:%s: " format, __FILE__, \
- __FUNCTION__, ## args)
-#else
-#define DEBUGP(format, args...)
-#endif
-
-static void pptp_nat_expected(struct ip_conntrack *ct,
- struct ip_conntrack_expect *exp)
-{
- struct ip_conntrack *master = ct->master;
- struct ip_conntrack_expect *other_exp;
- struct ip_conntrack_tuple t;
- struct ip_ct_pptp_master *ct_pptp_info;
- struct ip_nat_pptp *nat_pptp_info;
- struct ip_nat_range range;
-
- ct_pptp_info = &master->help.ct_pptp_info;
- nat_pptp_info = &master->nat.help.nat_pptp_info;
-
- /* And here goes the grand finale of corrosion... */
-
- if (exp->dir == IP_CT_DIR_ORIGINAL) {
- DEBUGP("we are PNS->PAC\n");
- /* therefore, build tuple for PAC->PNS */
- t.src.ip = master->tuplehash[IP_CT_DIR_REPLY].tuple.src.ip;
- t.src.u.gre.key = master->help.ct_pptp_info.pac_call_id;
- t.dst.ip = master->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip;
- t.dst.u.gre.key = master->help.ct_pptp_info.pns_call_id;
- t.dst.protonum = IPPROTO_GRE;
- } else {
- DEBUGP("we are PAC->PNS\n");
- /* build tuple for PNS->PAC */
- t.src.ip = master->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip;
- t.src.u.gre.key = master->nat.help.nat_pptp_info.pns_call_id;
- t.dst.ip = master->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.ip;
- t.dst.u.gre.key = master->nat.help.nat_pptp_info.pac_call_id;
- t.dst.protonum = IPPROTO_GRE;
- }
-
- DEBUGP("trying to unexpect other dir: ");
- DUMP_TUPLE(&t);
- other_exp = ip_conntrack_expect_find_get(&t);
- if (other_exp) {
- ip_conntrack_unexpect_related(other_exp);
- ip_conntrack_expect_put(other_exp);
- DEBUGP("success\n");
- } else {
- DEBUGP("not found!\n");
- }
-
- /* This must be a fresh one. */
- BUG_ON(ct->status & IPS_NAT_DONE_MASK);
-
- /* Change src to where master sends to */
- range.flags = IP_NAT_RANGE_MAP_IPS;
- range.min_ip = range.max_ip
- = ct->master->tuplehash[!exp->dir].tuple.dst.ip;
- if (exp->dir == IP_CT_DIR_ORIGINAL) {
- range.flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
- range.min = range.max = exp->saved_proto;
- }
- /* hook doesn't matter, but it has to do source manip */
- ip_nat_setup_info(ct, &range, NF_IP_POST_ROUTING);
-
- /* For DST manip, map port here to where it's expected. */
- range.flags = IP_NAT_RANGE_MAP_IPS;
- range.min_ip = range.max_ip
- = ct->master->tuplehash[!exp->dir].tuple.src.ip;
- if (exp->dir == IP_CT_DIR_REPLY) {
- range.flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
- range.min = range.max = exp->saved_proto;
- }
- /* hook doesn't matter, but it has to do destination manip */
- ip_nat_setup_info(ct, &range, NF_IP_PRE_ROUTING);
-}
-
-/* outbound packets == from PNS to PAC */
-static int
-pptp_outbound_pkt(struct sk_buff **pskb,
- struct ip_conntrack *ct,
- enum ip_conntrack_info ctinfo,
- struct PptpControlHeader *ctlh,
- union pptp_ctrl_union *pptpReq)
-
-{
- struct ip_ct_pptp_master *ct_pptp_info = &ct->help.ct_pptp_info;
- struct ip_nat_pptp *nat_pptp_info = &ct->nat.help.nat_pptp_info;
- u_int16_t msg;
- __be16 new_callid;
- unsigned int cid_off;
-
- new_callid = ct_pptp_info->pns_call_id;
-
- switch (msg = ntohs(ctlh->messageType)) {
- case PPTP_OUT_CALL_REQUEST:
- cid_off = offsetof(union pptp_ctrl_union, ocreq.callID);
- /* FIXME: ideally we would want to reserve a call ID
- * here. current netfilter NAT core is not able to do
- * this :( For now we use TCP source port. This breaks
- * multiple calls within one control session */
-
- /* save original call ID in nat_info */
- nat_pptp_info->pns_call_id = ct_pptp_info->pns_call_id;
-
- /* don't use tcph->source since we are at a DSTmanip
- * hook (e.g. PREROUTING) and pkt is not mangled yet */
- new_callid = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u.tcp.port;
-
- /* save new call ID in ct info */
- ct_pptp_info->pns_call_id = new_callid;
- break;
- case PPTP_IN_CALL_REPLY:
- cid_off = offsetof(union pptp_ctrl_union, icack.callID);
- break;
- case PPTP_CALL_CLEAR_REQUEST:
- cid_off = offsetof(union pptp_ctrl_union, clrreq.callID);
- break;
- default:
- DEBUGP("unknown outbound packet 0x%04x:%s\n", msg,
- (msg <= PPTP_MSG_MAX)?
- pptp_msg_name[msg]:pptp_msg_name[0]);
- /* fall through */
-
- case PPTP_SET_LINK_INFO:
- /* only need to NAT in case PAC is behind NAT box */
- case PPTP_START_SESSION_REQUEST:
- case PPTP_START_SESSION_REPLY:
- case PPTP_STOP_SESSION_REQUEST:
- case PPTP_STOP_SESSION_REPLY:
- case PPTP_ECHO_REQUEST:
- case PPTP_ECHO_REPLY:
- /* no need to alter packet */
- return NF_ACCEPT;
- }
-
- /* only OUT_CALL_REQUEST, IN_CALL_REPLY, CALL_CLEAR_REQUEST pass
- * down to here */
- DEBUGP("altering call id from 0x%04x to 0x%04x\n",
- ntohs(REQ_CID(pptpReq, cid_off)), ntohs(new_callid));
-
- /* mangle packet */
- if (ip_nat_mangle_tcp_packet(pskb, ct, ctinfo,
- cid_off + sizeof(struct pptp_pkt_hdr) +
- sizeof(struct PptpControlHeader),
- sizeof(new_callid), (char *)&new_callid,
- sizeof(new_callid)) == 0)
- return NF_DROP;
-
- return NF_ACCEPT;
-}
-
-static void
-pptp_exp_gre(struct ip_conntrack_expect *expect_orig,
- struct ip_conntrack_expect *expect_reply)
-{
- struct ip_conntrack *ct = expect_orig->master;
- struct ip_ct_pptp_master *ct_pptp_info = &ct->help.ct_pptp_info;
- struct ip_nat_pptp *nat_pptp_info = &ct->nat.help.nat_pptp_info;
-
- /* save original PAC call ID in nat_info */
- nat_pptp_info->pac_call_id = ct_pptp_info->pac_call_id;
-
- /* alter expectation for PNS->PAC direction */
- expect_orig->saved_proto.gre.key = ct_pptp_info->pns_call_id;
- expect_orig->tuple.src.u.gre.key = nat_pptp_info->pns_call_id;
- expect_orig->tuple.dst.u.gre.key = ct_pptp_info->pac_call_id;
- expect_orig->dir = IP_CT_DIR_ORIGINAL;
-
- /* alter expectation for PAC->PNS direction */
- expect_reply->saved_proto.gre.key = nat_pptp_info->pns_call_id;
- expect_reply->tuple.src.u.gre.key = nat_pptp_info->pac_call_id;
- expect_reply->tuple.dst.u.gre.key = ct_pptp_info->pns_call_id;
- expect_reply->dir = IP_CT_DIR_REPLY;
-}
-
-/* inbound packets == from PAC to PNS */
-static int
-pptp_inbound_pkt(struct sk_buff **pskb,
- struct ip_conntrack *ct,
- enum ip_conntrack_info ctinfo,
- struct PptpControlHeader *ctlh,
- union pptp_ctrl_union *pptpReq)
-{
- struct ip_nat_pptp *nat_pptp_info = &ct->nat.help.nat_pptp_info;
- u_int16_t msg;
- __be16 new_pcid;
- unsigned int pcid_off;
-
- new_pcid = nat_pptp_info->pns_call_id;
-
- switch (msg = ntohs(ctlh->messageType)) {
- case PPTP_OUT_CALL_REPLY:
- pcid_off = offsetof(union pptp_ctrl_union, ocack.peersCallID);
- break;
- case PPTP_IN_CALL_CONNECT:
- pcid_off = offsetof(union pptp_ctrl_union, iccon.peersCallID);
- break;
- case PPTP_IN_CALL_REQUEST:
- /* only need to nat in case PAC is behind NAT box */
- return NF_ACCEPT;
- case PPTP_WAN_ERROR_NOTIFY:
- pcid_off = offsetof(union pptp_ctrl_union, wanerr.peersCallID);
- break;
- case PPTP_CALL_DISCONNECT_NOTIFY:
- pcid_off = offsetof(union pptp_ctrl_union, disc.callID);
- break;
- case PPTP_SET_LINK_INFO:
- pcid_off = offsetof(union pptp_ctrl_union, setlink.peersCallID);
- break;
-
- default:
- DEBUGP("unknown inbound packet %s\n", (msg <= PPTP_MSG_MAX)?
- pptp_msg_name[msg]:pptp_msg_name[0]);
- /* fall through */
-
- case PPTP_START_SESSION_REQUEST:
- case PPTP_START_SESSION_REPLY:
- case PPTP_STOP_SESSION_REQUEST:
- case PPTP_STOP_SESSION_REPLY:
- case PPTP_ECHO_REQUEST:
- case PPTP_ECHO_REPLY:
- /* no need to alter packet */
- return NF_ACCEPT;
- }
-
- /* only OUT_CALL_REPLY, IN_CALL_CONNECT, IN_CALL_REQUEST,
- * WAN_ERROR_NOTIFY, CALL_DISCONNECT_NOTIFY pass down here */
-
- /* mangle packet */
- DEBUGP("altering peer call id from 0x%04x to 0x%04x\n",
- ntohs(REQ_CID(pptpReq, pcid_off)), ntohs(new_pcid));
-
- if (ip_nat_mangle_tcp_packet(pskb, ct, ctinfo,
- pcid_off + sizeof(struct pptp_pkt_hdr) +
- sizeof(struct PptpControlHeader),
- sizeof(new_pcid), (char *)&new_pcid,
- sizeof(new_pcid)) == 0)
- return NF_DROP;
- return NF_ACCEPT;
-}
-
-
-extern int __init ip_nat_proto_gre_init(void);
-extern void __exit ip_nat_proto_gre_fini(void);
-
-static int __init ip_nat_helper_pptp_init(void)
-{
- int ret;
-
- DEBUGP("%s: registering NAT helper\n", __FILE__);
-
- ret = ip_nat_proto_gre_init();
- if (ret < 0)
- return ret;
-
- BUG_ON(rcu_dereference(ip_nat_pptp_hook_outbound));
- rcu_assign_pointer(ip_nat_pptp_hook_outbound, pptp_outbound_pkt);
-
- BUG_ON(rcu_dereference(ip_nat_pptp_hook_inbound));
- rcu_assign_pointer(ip_nat_pptp_hook_inbound, pptp_inbound_pkt);
-
- BUG_ON(rcu_dereference(ip_nat_pptp_hook_exp_gre));
- rcu_assign_pointer(ip_nat_pptp_hook_exp_gre, pptp_exp_gre);
-
- BUG_ON(rcu_dereference(ip_nat_pptp_hook_expectfn));
- rcu_assign_pointer(ip_nat_pptp_hook_expectfn, pptp_nat_expected);
-
- printk("ip_nat_pptp version %s loaded\n", IP_NAT_PPTP_VERSION);
- return 0;
-}
-
-static void __exit ip_nat_helper_pptp_fini(void)
-{
- DEBUGP("cleanup_module\n" );
-
- rcu_assign_pointer(ip_nat_pptp_hook_expectfn, NULL);
- rcu_assign_pointer(ip_nat_pptp_hook_exp_gre, NULL);
- rcu_assign_pointer(ip_nat_pptp_hook_inbound, NULL);
- rcu_assign_pointer(ip_nat_pptp_hook_outbound, NULL);
- synchronize_rcu();
-
- ip_nat_proto_gre_fini();
-
- printk("ip_nat_pptp version %s unloaded\n", IP_NAT_PPTP_VERSION);
-}
-
-module_init(ip_nat_helper_pptp_init);
-module_exit(ip_nat_helper_pptp_fini);
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-25 11:28:58 +0000