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Index: src/util.c
===================================================================
--- src/util.c (revision 2436)
+++ src/util.c (working copy)
@@ -16,8 +16,9 @@
#include <netdb.h>
#include <tcpd.h>
#include <sys/limits.h>
-#include <sys/wait.h>
+#include <sys/socket.h>
#include <sys/sysctl.h>
+#include <sys/wait.h>
#include <net/route.h>
#include <netinet/if_ether.h>
#include <net/ethernet.h>
@@ -1545,4 +1546,52 @@ IfaceSetFlag(const char *ifname, int value)
}
close(s);
return (0);
+}
+
+/*
+ * Obtain some data, peer (source) and destination addresses of SOCK_DGRAM IPv4 UDP request.
+ */
+ssize_t GetDataAddrs(int sock, void *dbuf, size_t dbufsize,
+ struct sockaddr_storage *peer, socklen_t peer_len,
+ struct u_addr *addr)
+{
+ struct {
+ struct msghdr msg;
+ struct iovec iov;
+ } b;
+ union { /* ensure correct alignment for space */
+ struct cmsghdr cm;
+ char space[CMSG_SPACE(sizeof(struct in_addr))];
+ } buf;
+
+ struct cmsghdr *p;
+ ssize_t size;
+
+ /* Sanity check */
+ if (addr->family != AF_INET) {
+ errno = EAFNOSUPPORT;
+ return (-1);
+ }
+
+ b.msg.msg_name = peer;
+ b.msg.msg_namelen = peer_len;
+ b.msg.msg_iov = &b.iov;
+ b.msg.msg_iovlen = 1;
+ b.msg.msg_control = &buf;
+ b.msg.msg_controllen = sizeof(buf);
+ b.msg.msg_flags = 0;
+
+ b.iov.iov_base = dbuf;
+ b.iov.iov_len = dbufsize;
+
+ if ((size = recvmsg(sock, &b.msg, 0)) < 0) {
+ Perror("%s: recvmsg: %s", __FUNCTION__, strerror(errno));
+ return (size);
+ }
+
+ p = CMSG_FIRSTHDR(&b.msg);
+ if (p && p->cmsg_level == IPPROTO_IP && p->cmsg_type == IP_RECVDSTADDR)
+ memcpy(&addr->u.ip4, CMSG_DATA(p), sizeof(addr->u.ip4));
+
+ return (size);
}
Index: src/util.h
===================================================================
--- src/util.h (revision 2436)
+++ src/util.h (working copy)
@@ -101,6 +101,10 @@ extern int GetPeerEther(struct u_addr *addr, struct so
extern void ppp_util_ascify(char *buf, size_t max, const char *bytes, size_t len);
extern int IfaceSetFlag(const char *ifname, int value);
+ssize_t GetDataAddrs(int sock, void *dbuf, size_t dbufsize,
+ struct sockaddr_storage *peer, socklen_t peer_len,
+ struct u_addr *addr);
+
#ifndef HAVE_NTOA_R
extern char *ether_ntoa_r(const struct ether_addr *n, char *a);
#endif
Index: src/l2tp.c
===================================================================
--- src/l2tp.c (revision 2436)
+++ src/l2tp.c (working copy)
@@ -1374,6 +1374,7 @@ L2tpServerEvent(int type, void *arg)
struct ngm_mkpeer mkpeer;
struct sockaddr_storage peer_sas;
struct sockaddr_storage sas;
+ struct u_addr server_addr;
const size_t bufsize = 8192;
u_int16_t *buf = NULL;
char hook[NG_HOOKSIZ];
@@ -1393,9 +1394,18 @@ L2tpServerEvent(int type, void *arg)
/* Allocate buffer */
buf = Malloc(MB_PHYS, bufsize);
+ u_addrcopy(&s->self_addr, &server_addr);
+
/* Read packet */
sas_len = sizeof(peer_sas);
- if ((len = recvfrom(s->sock, buf, bufsize, 0,
+
+ if (u_addrempty(&s->self_addr)) {
+ if ((len = GetDataAddrs(s->sock, buf, bufsize,
+ &peer_sas, sas_len, &server_addr)) == -1) {
+ Perror("L2TP: GetDataAddrs");
+ goto fail;
+ }
+ } else if ((len = recvfrom(s->sock, buf, bufsize, 0,
(struct sockaddr *)&peer_sas, &sas_len)) == -1) {
Perror("L2TP: recvfrom");
goto fail;
@@ -1415,9 +1425,23 @@ L2tpServerEvent(int type, void *arg)
tun->self_port = s->self_port;
tun->alive = 1;
- Log(LG_PHYS, ("Incoming L2TP packet from %s %d",
- u_addrtoa(&tun->peer_addr, namebuf, sizeof(namebuf)), tun->peer_port));
+ if (u_addrempty(&tun->self_addr))
+ u_addrcopy(&server_addr, &tun->self_addr);
+ if (u_addrempty(&tun->self_addr))
+ Log(LG_PHYS, ("Incoming L2TP packet from %s %d",
+ u_addrtoa(&tun->peer_addr, namebuf, sizeof(namebuf)),
+ tun->peer_port));
+ else {
+ char buf3[INET_ADDRSTRLEN];
+
+ Log(LG_PHYS, ("Incoming L2TP packet from %s %d to %s %d",
+ u_addrtoa(&tun->peer_addr, namebuf, sizeof(namebuf)),
+ tun->peer_port,
+ u_addrtoa(&tun->self_addr, buf3, sizeof(buf3)),
+ tun->self_port));
+ }
+
/* Examine all L2TP links to get best possible fit tunnel parameters. */
for (k = 0; k < gNumLinks; k++) {
Link l2;
@@ -1552,7 +1576,7 @@ L2tpServerEvent(int type, void *arg)
}
/* Bind socket to a new port */
- u_addrtosockaddr(&s->self_addr,s->self_port,&sas);
+ u_addrtosockaddr(&tun->self_addr,tun->self_port,&sas);
if (NgSendMsg(csock, namebuf, NGM_KSOCKET_COOKIE,
NGM_KSOCKET_BIND, &sas, sas.ss_len) == -1) {
Perror("L2TP: bind");
@@ -1649,6 +1673,10 @@ L2tpListen(Link l)
SO_REUSEPORT, &one, sizeof(one)) == -1) {
Perror("L2TP: setsockopt");
goto fail;
+ }
+ if (u_addrempty(&s->self_addr)) {
+ int on = 1;
+ setsockopt(s->sock, IPPROTO_IP, IP_RECVDSTADDR, &on, sizeof(on));
}
u_addrtosockaddr(&s->self_addr, s->self_port, &sa);
if (bind(s->sock, (struct sockaddr *)&sa, sa.ss_len) == -1) {
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