git: db72bd31c56b - main - net/mpd5: Re-implement improvement for multi-homed L2TP server

The branch main has been updated by eugen:

URL: https://cgit.FreeBSD.org/ports/commit/?id=db72bd31c56b6a3eb502aa2a650a1aab302b43ca

commit db72bd31c56b6a3eb502aa2a650a1aab302b43ca
Author:     Eugene Grosbein <eugen@FreeBSD.org>
AuthorDate: 2021-12-04 12:56:13 +0000
Commit:     Eugene Grosbein <eugen@FreeBSD.org>
CommitDate: 2021-12-04 12:58:09 +0000

    net/mpd5: Re-implement improvement for multi-homed L2TP server
    
    Import upstream r2437-r2440:
    
    Use IP_RECVDSTADDR socket option for IPv4 L2TP server
    with unspecified self address (0.0.0.0) to determine destination
    IP address of incoming request and bind new tunnel to right address.
    This unbreaks multihomed L2TP server setup.
---
 net/mpd5/Makefile                    |   2 +-
 net/mpd5/files/patch-l2tp-multihomed | 161 +++++++++++++++++++++++++++++++++++
 2 files changed, 162 insertions(+), 1 deletion(-)

diff --git a/net/mpd5/Makefile b/net/mpd5/Makefile
index 206baa1d9059..9e4ed26ee476 100644
--- a/net/mpd5/Makefile
+++ b/net/mpd5/Makefile
@@ -2,7 +2,7 @@
 
 PORTNAME=	mpd
 DISTVERSION=	5.9
-PORTREVISION=	4
+PORTREVISION=	6
 CATEGORIES=	net
 MASTER_SITES=	SF/${PORTNAME}/Mpd5/Mpd-${PORTVERSION}
 PKGNAMESUFFIX=	5
diff --git a/net/mpd5/files/patch-l2tp-multihomed b/net/mpd5/files/patch-l2tp-multihomed
new file mode 100644
index 000000000000..33ec387c37c4
--- /dev/null
+++ b/net/mpd5/files/patch-l2tp-multihomed
@@ -0,0 +1,161 @@
+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) {