* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
- *
- * Helper functions to get/set addresses of UDP packets
- * based on recvfromto by Miquel van Smoorenburg
- *
- * recvfromto Like recvfrom, but also stores the destination
- * IP address. Useful on multihomed hosts.
- *
- * Should work on Linux and BSD.
- *
- * Copyright (C) 2002 Miquel van Smoorenburg.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2 of the License, or (at your option) any later version.
- *
- * sendfromto added 18/08/2003, Jan Berkel <jan@sitadelle.com>
- * Works on Linux and FreeBSD (5.x)
- *
- * Version: $Id$
*/
-#include <freeradius-devel/ident.h>
+/**
+ * $Id$
+ * @file udpfromto.c
+ * @brief Like recvfrom, but also stores the destination IP address. Useful on multihomed hosts.
+ *
+ * @copyright 2007 Alan DeKok <aland@deployingradius.com>
+ * @copyright 2002 Miquel van Smoorenburg
+ */
RCSID("$Id$")
#include <freeradius-devel/udpfromto.h>
#ifdef WITH_UDPFROMTO
#ifdef HAVE_SYS_UIO_H
-#include <sys/uio.h>
+# include <sys/uio.h>
#endif
#include <fcntl.h>
+/*
+ * More portability idiocy
+ * Mac OSX Lion doesn't define SOL_IP. But IPPROTO_IP works.
+ */
+#ifndef SOL_IP
+# define SOL_IP IPPROTO_IP
+#endif
+
+/*
+ * glibc 2.4 and uClibc 0.9.29 introduce IPV6_RECVPKTINFO etc. and
+ * change IPV6_PKTINFO This is only supported in Linux kernel >=
+ * 2.6.14
+ *
+ * This is only an approximation because the kernel version that libc
+ * was compiled against could be older or newer than the one being
+ * run. But this should not be a problem -- we just keep using the
+ * old kernel interface.
+ */
+#ifdef __linux__
+# ifdef IPV6_RECVPKTINFO
+# include <linux/version.h>
+# if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,14)
+# ifdef IPV6_2292PKTINFO
+# undef IPV6_RECVPKTINFO
+# undef IPV6_PKTINFO
+# define IPV6_RECVPKTINFO IPV6_2292PKTINFO
+# define IPV6_PKTINFO IPV6_2292PKTINFO
+# endif
+# endif
+/* Fall back to the legacy socket option if IPV6_RECVPKTINFO isn't defined */
+# elif defined(IPV6_2292PKTINFO)
+# define IPV6_RECVPKTINFO IPV6_2292PKTINFO
+# endif
+#endif
+
+/*
+ * Linux requires IPV6_RECVPKTINFO for the setsockopt() call,
+ * but sendmsg() and recvmsg() require IPV6_PKTINFO. <sigh>
+ *
+ * We want all *other* (i.e. sane) systems to use IPV6_PKTINFO
+ * for all three calls.
+ */
+#ifdef IPV6_PKTINFO
+# ifdef __linux__
+# ifdef IPV6_RECVPKTINFO
+# define FR_IPV6_RECVPKTINFO IPV6_RECVPKTINFO
+/* Fallback to to using recvfrom */
+# else
+# undef IPV6_RECVPKTINFO
+# undef IPV6_PKTINFO
+# endif
+# else
+# define FR_IPV6_RECVPKTINFO IPV6_PKTINFO
+# endif
+#endif
int udpfromto_init(int s)
{
- int err = -1, opt = 1;
+ int proto, flag = 0, opt = 1;
+ struct sockaddr_storage si;
+ socklen_t si_len = sizeof(si);
+
errno = ENOSYS;
-#ifdef HAVE_IP_PKTINFO
- /* Set the IP_PKTINFO option (Linux). */
- err = setsockopt(s, SOL_IP, IP_PKTINFO, &opt, sizeof(opt));
-#endif
-#ifdef HAVE_IP_RECVDSTADDR
/*
- * Set the IP_RECVDSTADDR option (BSD).
- * Note: IP_RECVDSTADDR == IP_SENDSRCADDR
+ * Clang analyzer doesn't see that getsockname initialises
+ * the memory passed to it.
*/
- err = setsockopt(s, IPPROTO_IP, IP_RECVDSTADDR, &opt, sizeof(opt));
+#ifdef __clang_analyzer__
+ memset(&si, 0, sizeof(si));
#endif
- return err;
+
+ if (getsockname(s, (struct sockaddr *) &si, &si_len) < 0) {
+ return -1;
+ }
+
+ if (si.ss_family == AF_INET) {
+#ifdef HAVE_IP_PKTINFO
+ /*
+ * Linux
+ */
+ proto = SOL_IP;
+ flag = IP_PKTINFO;
+#else
+# ifdef IP_RECVDSTADDR
+
+ /*
+ * Set the IP_RECVDSTADDR option (BSD). Note:
+ * IP_RECVDSTADDR == IP_SENDSRCADDR
+ */
+ proto = IPPROTO_IP;
+ flag = IP_RECVDSTADDR;
+# else
+ return -1;
+# endif
+#endif
+
+#ifdef AF_INET6
+ } else if (si.ss_family == AF_INET6) {
+# ifdef IPV6_PKTINFO
+ /*
+ * This should actually be standard IPv6
+ */
+ proto = IPPROTO_IPV6;
+
+ /*
+ * Work around Linux-specific hackery.
+ */
+ flag = FR_IPV6_RECVPKTINFO;
+#else
+# ifdef EPROTONOSUPPORT
+ errno = EPROTONOSUPPORT;
+# endif
+ return -1;
+# endif
+#endif
+ } else {
+ /*
+ * Unknown AF.
+ */
+ return -1;
+ }
+
+ return setsockopt(s, proto, flag, &opt, sizeof(opt));
}
int recvfromto(int s, void *buf, size_t len, int flags,
- struct sockaddr *from, socklen_t *fromlen,
- struct sockaddr *to, socklen_t *tolen)
+ struct sockaddr *from, socklen_t *fromlen,
+ struct sockaddr *to, socklen_t *tolen)
{
-#if defined(HAVE_IP_PKTINFO) || defined(HAVE_IP_RECVDSTADDR)
struct msghdr msgh;
struct cmsghdr *cmsg;
struct iovec iov;
char cbuf[256];
int err;
+ struct sockaddr_storage si;
+ socklen_t si_len = sizeof(si);
+#if !defined(IP_PKTINFO) && !defined(IP_RECVDSTADDR) && !defined(IPV6_PKTINFO)
/*
- * If from or to are set, they must be big enough
- * to store a struct sockaddr_in.
+ * If the recvmsg() flags aren't defined, fall back to
+ * using recvfrom().
*/
- if ((from && (!fromlen || *fromlen < sizeof(struct sockaddr_in))) ||
- (to && (!tolen || *tolen < sizeof(struct sockaddr_in)))) {
- errno = EINVAL;
+ to = NULL:
+#endif
+
+ /*
+ * Catch the case where the caller passes invalid arguments.
+ */
+ if (!to || !tolen) return recvfrom(s, buf, len, flags, from, fromlen);
+
+ /*
+ * Clang analyzer doesn't see that getsockname initialises
+ * the memory passed to it.
+ */
+#ifdef __clang_analyzer__
+ memset(&si, 0, sizeof(si));
+#endif
+
+ /*
+ * recvmsg doesn't provide sin_port so we have to
+ * retrieve it using getsockname().
+ */
+ if (getsockname(s, (struct sockaddr *)&si, &si_len) < 0) {
return -1;
}
/*
- * IP_PKTINFO / IP_RECVDSTADDR don't provide sin_port so we have to
- * retrieve it using getsockname().
+ * Initialize the 'to' address. It may be INADDR_ANY here,
+ * with a more specific address given by recvmsg(), below.
*/
- if (to) {
- struct sockaddr_in si;
- socklen_t l = sizeof(si);
-
- ((struct sockaddr_in *)to)->sin_family = AF_INET;
- ((struct sockaddr_in *)to)->sin_port = 0;
- l = sizeof(si);
- if (getsockname(s, (struct sockaddr *)&si, &l) == 0) {
- ((struct sockaddr_in *)to)->sin_port = si.sin_port;
- ((struct sockaddr_in *)to)->sin_addr = si.sin_addr;
+ if (si.ss_family == AF_INET) {
+#if !defined(IP_PKTINFO) && !defined(IP_RECVDSTADDR)
+ return recvfrom(s, buf, len, flags, from, fromlen);
+#else
+ struct sockaddr_in *dst = (struct sockaddr_in *) to;
+ struct sockaddr_in *src = (struct sockaddr_in *) &si;
+
+ if (*tolen < sizeof(*dst)) {
+ errno = EINVAL;
+ return -1;
}
- if (tolen) *tolen = sizeof(struct sockaddr_in);
+ *tolen = sizeof(*dst);
+ *dst = *src;
+#endif
+ }
+
+#ifdef AF_INET6
+ else if (si.ss_family == AF_INET6) {
+#if !defined(IPV6_PKTINFO)
+ return recvfrom(s, buf, len, flags, from, fromlen);
+#else
+ struct sockaddr_in6 *dst = (struct sockaddr_in6 *) to;
+ struct sockaddr_in6 *src = (struct sockaddr_in6 *) &si;
+
+ if (*tolen < sizeof(*dst)) {
+ errno = EINVAL;
+ return -1;
+ }
+ *tolen = sizeof(*dst);
+ *dst = *src;
+#endif
+ }
+#endif
+ /*
+ * Unknown address family.
+ */
+ else {
+ errno = EINVAL;
+ return -1;
}
/* Set up iov and msgh structures. */
+ memset(&cbuf, 0, sizeof(cbuf));
memset(&msgh, 0, sizeof(struct msghdr));
iov.iov_base = buf;
iov.iov_len = len;
if ((err = recvmsg(s, &msgh, flags)) < 0) {
return err;
}
+
if (fromlen) *fromlen = msgh.msg_namelen;
/* Process auxiliary received data in msgh */
cmsg != NULL;
cmsg = CMSG_NXTHDR(&msgh,cmsg)) {
-# ifdef HAVE_IP_PKTINFO
- if (cmsg->cmsg_level == SOL_IP
- && cmsg->cmsg_type == IP_PKTINFO) {
+#ifdef IP_PKTINFO
+ if ((cmsg->cmsg_level == SOL_IP) &&
+ (cmsg->cmsg_type == IP_PKTINFO)) {
struct in_pktinfo *i =
- (struct in_pktinfo *)CMSG_DATA(cmsg);
- if (to) {
- ((struct sockaddr_in *)to)->sin_addr =
- i->ipi_addr;
- if (tolen) *tolen = sizeof(struct sockaddr_in);
- }
+ (struct in_pktinfo *) CMSG_DATA(cmsg);
+ ((struct sockaddr_in *)to)->sin_addr = i->ipi_addr;
+ *tolen = sizeof(struct sockaddr_in);
+ break;
+ }
+#endif
+
+#ifdef IP_RECVDSTADDR
+ if ((cmsg->cmsg_level == IPPROTO_IP) &&
+ (cmsg->cmsg_type == IP_RECVDSTADDR)) {
+ struct in_addr *i = (struct in_addr *) CMSG_DATA(cmsg);
+ ((struct sockaddr_in *)to)->sin_addr = *i;
+ *tolen = sizeof(struct sockaddr_in);
break;
}
-# endif
-
-# ifdef HAVE_IP_RECVDSTADDR
- if (cmsg->cmsg_level == IPPROTO_IP
- && cmsg->cmsg_type == IP_RECVDSTADDR) {
- struct in_addr *i = (struct in_addr *)CMSG_DATA(cmsg);
- if (to) {
- ((struct sockaddr_in *)to)->sin_addr = *i;
- if (tolen) *tolen = sizeof(struct sockaddr_in);
- }
+#endif
+
+#ifdef IPV6_PKTINFO
+ if ((cmsg->cmsg_level == IPPROTO_IPV6) &&
+ (cmsg->cmsg_type == IPV6_PKTINFO)) {
+ struct in6_pktinfo *i =
+ (struct in6_pktinfo *) CMSG_DATA(cmsg);
+ ((struct sockaddr_in6 *)to)->sin6_addr = i->ipi6_addr;
+ *tolen = sizeof(struct sockaddr_in6);
break;
}
-# endif
+#endif
}
+
return err;
-#else
- /* fallback: call recvfrom */
- return recvfrom(s, buf, len, flags, from, fromlen);
-#endif /* defined(HAVE_IP_PKTINFO) || defined(HAVE_IP_RECVDSTADDR) */
}
int sendfromto(int s, void *buf, size_t len, int flags,
- struct sockaddr *from, socklen_t fromlen,
- struct sockaddr *to, socklen_t tolen)
+ struct sockaddr *from, socklen_t fromlen,
+ struct sockaddr *to, socklen_t tolen)
{
-#if defined(HAVE_IP_PKTINFO) || defined(HAVE_IP_SENDSRCADDR)
struct msghdr msgh;
struct cmsghdr *cmsg;
struct iovec iov;
-# ifdef HAVE_IP_PKTINFO
- char cmsgbuf[CMSG_SPACE(sizeof(struct in_pktinfo))];
- struct in_pktinfo pktinfo, *pktinfo_ptr;
- memset(&pktinfo, 0, sizeof(struct in_pktinfo));
-# endif
- struct sockaddr_in *s4;
+ char cbuf[256];
-# ifdef HAVE_IP_SENDSRCADDR
- char cmsgbuf[CMSG_SPACE(sizeof(struct in_addr))];
-# endif
+#ifdef __FreeBSD__
+ /*
+ * FreeBSD is extra pedantic about the use of IP_SENDSRCADDR,
+ * and sendmsg will fail with EINVAL if IP_SENDSRCADDR is used
+ * with a socket which is bound to something other than
+ * INADDR_ANY
+ */
+ struct sockaddr bound;
+ socklen_t bound_len = sizeof(bound);
- s4 = (struct sockaddr_in *) from;
+ if (getsockname(s, &bound, &bound_len) < 0) {
+ return -1;
+ }
+ switch (bound.sa_family) {
+ case AF_INET:
+ if (((struct sockaddr_in *) &bound)->sin_addr.s_addr != INADDR_ANY) {
+ from = NULL;
+ }
+ break;
+
+ case AF_INET6:
+ if (!IN6_IS_ADDR_UNSPECIFIED(&((struct sockaddr_in6 *) &bound)->sin6_addr))) {
+ from = NULL;
+ }
+ break;
+ }
+#else
+# if !defined(IP_PKTINFO) && !defined(IP_SENDSRCADDR) && !defined(IPV6_PKTINFO)
/*
- * Source is unset, empty, or unspecified,
- * fall back to sendto().
+ * If the sendmsg() flags aren't defined, fall back to
+ * using sendto().
*/
- if (!s4 || (fromlen == 0) || (s4->sin_family == AF_UNSPEC)) {
+ from = NULL;
+# endif
+#endif
+
+ /*
+ * Catch the case where the caller passes invalid arguments.
+ */
+ if (!from || (fromlen == 0) || (from->sa_family == AF_UNSPEC)) {
return sendto(s, buf, len, flags, to, tolen);
}
- /* Set up iov and msgh structures. */
- memset(&msgh, 0, sizeof(struct msghdr));
+ /* Set up control buffer iov and msgh structures. */
+ memset(&cbuf, 0, sizeof(cbuf));
+ memset(&msgh, 0, sizeof(msgh));
+ memset(&iov, 0, sizeof(iov));
iov.iov_base = buf;
iov.iov_len = len;
msgh.msg_iov = &iov;
msgh.msg_iovlen = 1;
- msgh.msg_control = cmsgbuf;
- msgh.msg_controllen = sizeof(cmsgbuf);
msgh.msg_name = to;
msgh.msg_namelen = tolen;
- cmsg = CMSG_FIRSTHDR(&msgh);
-
-# ifdef HAVE_IP_PKTINFO
- cmsg->cmsg_level = SOL_IP;
- cmsg->cmsg_type = IP_PKTINFO;
- cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_pktinfo));
- pktinfo.ipi_spec_dst = ((struct sockaddr_in *)from)->sin_addr;
- pktinfo_ptr = (struct in_pktinfo *)CMSG_DATA(cmsg);
- memcpy(pktinfo_ptr, &pktinfo, sizeof(struct in_pktinfo));
-# endif
-# ifdef HAVE_IP_SENDSRCADDR
- cmsg->cmsg_level = IPPROTO_IP;
- cmsg->cmsg_type = IP_SENDSRCADDR;
- cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_addr));
- memcpy((struct in_addr *)CMSG_DATA(cmsg),
- &((struct sockaddr_in *)from)->sin_addr, sizeof(struct in_addr));
-# endif
+ if (from->sa_family == AF_INET) {
+#if !defined(IP_PKTINFO) && !defined(IP_SENDSRCADDR)
+ return sendto(s, buf, len, flags, to, tolen);
+#else
+ struct sockaddr_in *s4 = (struct sockaddr_in *) from;
+
+# ifdef IP_PKTINFO
+ struct in_pktinfo *pkt;
+
+ msgh.msg_control = cbuf;
+ msgh.msg_controllen = CMSG_SPACE(sizeof(*pkt));
+
+ cmsg = CMSG_FIRSTHDR(&msgh);
+ cmsg->cmsg_level = SOL_IP;
+ cmsg->cmsg_type = IP_PKTINFO;
+ cmsg->cmsg_len = CMSG_LEN(sizeof(*pkt));
+
+ pkt = (struct in_pktinfo *) CMSG_DATA(cmsg);
+ memset(pkt, 0, sizeof(*pkt));
+ pkt->ipi_spec_dst = s4->sin_addr;
+# endif
+
+# ifdef IP_SENDSRCADDR
+ struct in_addr *in;
+
+ msgh.msg_control = cbuf;
+ msgh.msg_controllen = CMSG_SPACE(sizeof(*in));
+
+ cmsg = CMSG_FIRSTHDR(&msgh);
+ cmsg->cmsg_level = IPPROTO_IP;
+ cmsg->cmsg_type = IP_SENDSRCADDR;
+ cmsg->cmsg_len = CMSG_LEN(sizeof(*in));
+
+ in = (struct in_addr *) CMSG_DATA(cmsg);
+ *in = s4->sin_addr;
+# endif
+#endif /* IP_PKTINFO or IP_SENDSRCADDR */
+ }
+
+#ifdef AF_INET6
+ else if (from->sa_family == AF_INET6) {
+# if !defined(IPV6_PKTINFO)
+ return sendto(s, buf, len, flags, to, tolen);
+# else
+ struct sockaddr_in6 *s6 = (struct sockaddr_in6 *) from;
+
+ struct in6_pktinfo *pkt;
+
+ msgh.msg_control = cbuf;
+ msgh.msg_controllen = CMSG_SPACE(sizeof(*pkt));
+
+ cmsg = CMSG_FIRSTHDR(&msgh);
+ cmsg->cmsg_level = IPPROTO_IPV6;
+ cmsg->cmsg_type = IPV6_PKTINFO;
+ cmsg->cmsg_len = CMSG_LEN(sizeof(*pkt));
+
+ pkt = (struct in6_pktinfo *) CMSG_DATA(cmsg);
+ memset(pkt, 0, sizeof(*pkt));
+ pkt->ipi6_addr = s6->sin6_addr;
+# endif /* IPV6_PKTINFO */
+ }
+#endif
+
+ /*
+ * Unknown address family.
+ */
+ else {
+ errno = EINVAL;
+ return -1;
+ }
return sendmsg(s, &msgh, flags);
-#else
- /* fallback: call sendto() */
- return sendto(s, buf, len, flags, to, tolen);
-#endif /* defined(HAVE_IP_PKTINFO) || defined (HAVE_IP_SENDSRCADDR) */
}
* reply packet should originate from virtual IP and not
* from the default interface the alias is bound to
*/
+# include <sys/wait.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <arpa/inet.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-
-#define DEF_PORT 20000 /* default port to listen on */
-#define DESTIP "127.0.0.1" /* send packet to localhost per default */
-#define TESTSTRING "foo" /* what to send */
-#define TESTLEN 4 /* 4 bytes */
+# define DEF_PORT 20000 /* default port to listen on */
+# define DESTIP "127.0.0.1" /* send packet to localhost per default */
+# define TESTSTRING "foo" /* what to send */
+# define TESTLEN 4 /* 4 bytes */
int main(int argc, char **argv)
{
struct sockaddr_in from, to, in;
char buf[TESTLEN];
char *destip = DESTIP;
- int port = DEF_PORT;
+ uint16_t port = DEF_PORT;
int n, server_socket, client_socket, fl, tl, pid;
if (argc > 1) destip = argv[1];
client_socket = socket(PF_INET, SOCK_DGRAM, 0);
if (udpfromto_init(client_socket) != 0) {
perror("udpfromto_init");
- _exit(0);
+ fr_exit_now(0);
}
/* bind client on different port */
in.sin_port = htons(port+1);
if (bind(client_socket, (struct sockaddr *)&in, sizeof(in)) < 0) {
perror("client: bind");
- _exit(0);
+ fr_exit_now(0);
}
in.sin_port = htons(port);
if (sendto(client_socket, TESTSTRING, TESTLEN, 0,
(struct sockaddr *)&in, sizeof(in)) < 0) {
perror("client: sendto");
- _exit(0);
+ fr_exit_now(0);
}
printf("client: waiting for reply from server on INADDR_ANY:%d\n", port+1);
(struct sockaddr *)&from, &fl,
(struct sockaddr *)&to, &tl)) < 0) {
perror("client: recvfromto");
- _exit(0);
+ fr_exit_now(0);
}
printf("client: received a packet of %d bytes [%s] ", n, buf);
printf(" dst ip:port %s:%d)\n",
inet_ntoa(to.sin_addr), ntohs(to.sin_port));
- _exit(0);
+ fr_exit_now(0);
}
#endif /* TESTING */