*
*/
-#include <linux/config.h>
#include <linux/module.h>
#include <linux/ip.h>
#include <linux/tcp.h>
#define IP_NAT_PPTP_VERSION "3.0"
+#define REQ_CID(req, off) (*(u_int16_t *)((char *)(req) + (off)))
+
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Harald Welte <laforge@gnumonks.org>");
MODULE_DESCRIPTION("Netfilter NAT helper module for PPTP");
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;
DEBUGP("not found!\n");
}
- ip_nat_follow_master(ct, exp);
+ /* 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 */
{
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, *cid = NULL, new_callid;
+ u_int16_t msg, new_callid;
+ unsigned int cid_off;
new_callid = htons(ct_pptp_info->pns_call_id);
switch (msg = ntohs(ctlh->messageType)) {
case PPTP_OUT_CALL_REQUEST:
- cid = &pptpReq->ocreq.callID;
+ 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
ct_pptp_info->pns_call_id = ntohs(new_callid);
break;
case PPTP_IN_CALL_REPLY:
- cid = &pptpReq->icreq.callID;
+ cid_off = offsetof(union pptp_ctrl_union, icreq.callID);
break;
case PPTP_CALL_CLEAR_REQUEST:
- cid = &pptpReq->clrreq.callID;
+ cid_off = offsetof(union pptp_ctrl_union, clrreq.callID);
break;
default:
DEBUGP("unknown outbound packet 0x%04x:%s\n", msg,
/* only OUT_CALL_REQUEST, IN_CALL_REPLY, CALL_CLEAR_REQUEST pass
* down to here */
-
- IP_NF_ASSERT(cid);
-
DEBUGP("altering call id from 0x%04x to 0x%04x\n",
- ntohs(*cid), ntohs(new_callid));
+ ntohs(REQ_CID(pptpReq, cid_off)), ntohs(new_callid));
/* mangle packet */
if (ip_nat_mangle_tcp_packet(pskb, ct, ctinfo,
- (void *)cid - ((void *)ctlh - sizeof(struct pptp_pkt_hdr)),
- sizeof(new_callid),
- (char *)&new_callid,
- sizeof(new_callid)) == 0)
+ 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;
/* alter expectation for PNS->PAC direction */
invert_tuplepr(&inv_t, &expect_orig->tuple);
- expect_orig->saved_proto.gre.key = htons(nat_pptp_info->pac_call_id);
+ expect_orig->saved_proto.gre.key = htons(ct_pptp_info->pns_call_id);
expect_orig->tuple.src.u.gre.key = htons(nat_pptp_info->pns_call_id);
expect_orig->tuple.dst.u.gre.key = htons(ct_pptp_info->pac_call_id);
expect_orig->dir = IP_CT_DIR_ORIGINAL;
union pptp_ctrl_union *pptpReq)
{
struct ip_nat_pptp *nat_pptp_info = &ct->nat.help.nat_pptp_info;
- u_int16_t msg, new_cid = 0, new_pcid, *pcid = NULL, *cid = NULL;
-
- int ret = NF_ACCEPT, rv;
+ u_int16_t msg, new_cid = 0, new_pcid;
+ unsigned int pcid_off, cid_off = 0;
new_pcid = htons(nat_pptp_info->pns_call_id);
switch (msg = ntohs(ctlh->messageType)) {
case PPTP_OUT_CALL_REPLY:
- pcid = &pptpReq->ocack.peersCallID;
- cid = &pptpReq->ocack.callID;
+ pcid_off = offsetof(union pptp_ctrl_union, ocack.peersCallID);
+ cid_off = offsetof(union pptp_ctrl_union, ocack.callID);
break;
case PPTP_IN_CALL_CONNECT:
- pcid = &pptpReq->iccon.peersCallID;
+ 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 */
- break;
+ return NF_ACCEPT;
case PPTP_WAN_ERROR_NOTIFY:
- pcid = &pptpReq->wanerr.peersCallID;
+ pcid_off = offsetof(union pptp_ctrl_union, wanerr.peersCallID);
break;
case PPTP_CALL_DISCONNECT_NOTIFY:
- pcid = &pptpReq->disc.callID;
+ pcid_off = offsetof(union pptp_ctrl_union, disc.callID);
break;
case PPTP_SET_LINK_INFO:
- pcid = &pptpReq->setlink.peersCallID;
+ pcid_off = offsetof(union pptp_ctrl_union, setlink.peersCallID);
break;
default:
* WAN_ERROR_NOTIFY, CALL_DISCONNECT_NOTIFY pass down here */
/* mangle packet */
- IP_NF_ASSERT(pcid);
DEBUGP("altering peer call id from 0x%04x to 0x%04x\n",
- ntohs(*pcid), ntohs(new_pcid));
-
- rv = ip_nat_mangle_tcp_packet(pskb, ct, ctinfo,
- (void *)pcid - ((void *)ctlh - sizeof(struct pptp_pkt_hdr)),
- sizeof(new_pcid), (char *)&new_pcid,
- sizeof(new_pcid));
- if (rv != NF_ACCEPT)
- return rv;
+ 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;
if (new_cid) {
- IP_NF_ASSERT(cid);
DEBUGP("altering call id from 0x%04x to 0x%04x\n",
- ntohs(*cid), ntohs(new_cid));
- rv = ip_nat_mangle_tcp_packet(pskb, ct, ctinfo,
- (void *)cid - ((void *)ctlh - sizeof(struct pptp_pkt_hdr)),
- sizeof(new_cid),
- (char *)&new_cid,
- sizeof(new_cid));
- if (rv != NF_ACCEPT)
- return rv;
+ ntohs(REQ_CID(pptpReq, cid_off)), ntohs(new_cid));
+ if (ip_nat_mangle_tcp_packet(pskb, ct, ctinfo,
+ cid_off + sizeof(struct pptp_pkt_hdr) +
+ sizeof(struct PptpControlHeader),
+ sizeof(new_cid), (char *)&new_cid,
+ sizeof(new_cid)) == 0)
+ return NF_DROP;
}
-
- /* check for earlier return value of 'switch' above */
- if (ret != NF_ACCEPT)
- return ret;
-
- /* great, at least we don't need to resize packets */
return NF_ACCEPT;
}
extern int __init ip_nat_proto_gre_init(void);
extern void __exit ip_nat_proto_gre_fini(void);
-static int __init init(void)
+static int __init ip_nat_helper_pptp_init(void)
{
int ret;
return 0;
}
-static void __exit fini(void)
+static void __exit ip_nat_helper_pptp_fini(void)
{
DEBUGP("cleanup_module\n" );
printk("ip_nat_pptp version %s unloaded\n", IP_NAT_PPTP_VERSION);
}
-module_init(init);
-module_exit(fini);
+module_init(ip_nat_helper_pptp_init);
+module_exit(ip_nat_helper_pptp_fini);
projects / powerpc.git / blobdiff