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-rw-r--r--sysdep/linux/Modules1
-rw-r--r--sysdep/linux/sysio.h118
2 files changed, 119 insertions, 0 deletions
diff --git a/sysdep/linux/Modules b/sysdep/linux/Modules
index 4a99916..1b867d8 100644
--- a/sysdep/linux/Modules
+++ b/sysdep/linux/Modules
@@ -2,3 +2,4 @@
krt-scan.c
krt-scan.h
#endif
+sysio.h
diff --git a/sysdep/linux/sysio.h b/sysdep/linux/sysio.h
new file mode 100644
index 0000000..bef8a61
--- /dev/null
+++ b/sysdep/linux/sysio.h
@@ -0,0 +1,118 @@
+/*
+ * BIRD Internet Routing Daemon -- Linux Multicasting and Network Includes
+ *
+ * (c) 1998--1999 Martin Mares <mj@ucw.cz>
+ *
+ * Can be freely distributed and used under the terms of the GNU GPL.
+ */
+
+#ifdef IPV6
+#include <linux/in6.h> /* FIXMEv6: glibc variant? */
+
+#else
+
+/*
+ * Multicasting in Linux systems is a real mess. Not only different kernels
+ * have different interfaces, but also different libc's export it in different
+ * ways. Horrible.
+ */
+
+static inline char *sysio_mcast_setup(sock *s)
+{
+ int zero = 0;
+
+ if (ipa_nonzero(s->daddr))
+ {
+ if (
+#ifdef IP_DEFAULT_MULTICAST_TTL
+ s->ttl != IP_DEFAULT_MULTICAST_TTL &&
+#endif
+ setsockopt(s->fd, SOL_IP, IP_MULTICAST_TTL, &s->ttl, sizeof(s->ttl)) < 0)
+ return "IP_MULTICAST_TTL";
+ if (
+#ifdef IP_DEFAULT_MULTICAST_LOOP
+ IP_DEFAULT_MULTICAST_LOOP &&
+#endif
+ setsockopt(s->fd, SOL_IP, IP_MULTICAST_LOOP, &zero, sizeof(zero)) < 0)
+ return "IP_MULTICAST_LOOP";
+ }
+ return NULL;
+}
+
+#ifdef CONFIG_LINUX_MC_MREQN
+/*
+ * 2.1 and newer kernels use struct mreqn which passes ifindex, so no
+ * problems with unnumbered devices.
+ */
+
+#ifndef HAVE_STRUCT_IP_MREQN
+/* Several versions of glibc don't define this structure, so we have to do it ourselves */
+struct ip_mreqn
+{
+ struct in_addr imr_multiaddr; /* IP multicast address of group */
+ struct in_addr imr_address; /* local IP address of interface */
+ int imr_ifindex; /* Interface index */
+};
+#endif
+
+static inline char *sysio_mcast_join(sock *s)
+{
+ struct ip_mreqn mreq;
+ char *err;
+
+ if (err = sysio_mcast_setup(s))
+ return err;
+ mreq.imr_ifindex = s->iface->index;
+ set_inaddr(&mreq.imr_address, s->iface->addr->ip);
+ set_inaddr(&mreq.imr_multiaddr, s->daddr);
+ /* This defines where should we send _outgoing_ multicasts */
+ if (setsockopt(s->fd, SOL_IP, IP_MULTICAST_IF, &mreq, sizeof(mreq)) < 0)
+ return "IP_MULTICAST_IF";
+ /* And this one sets interface for _receiving_ multicasts from */
+ if (ipa_nonzero(s->saddr) && setsockopt(s->fd, SOL_IP, IP_ADD_MEMBERSHIP, &mreq, sizeof(mreq)) < 0)
+ return "IP_ADD_MEMBERSHIP";
+ return NULL;
+}
+#endif
+
+#if defined(CONFIG_LINUX_MC_MREQ) || defined(CONFIG_LINUX_MC_MREQ_BIND)
+/*
+ * Older kernels support only struct mreq which matches interfaces by their
+ * addresses and thus fails on unnumbered devices. On newer 2.0 kernels
+ * we can use SO_BINDTODEVICE to circumvent this problem.
+ */
+
+#include <net/if.h>
+
+static inline char *sysio_mcast_join(sock *s)
+{
+ struct in_addr mreq;
+ struct ip_mreq mreq_add;
+ char *err;
+
+ if (err = sysio_mcast_setup(s))
+ return err;
+ set_inaddr(&mreq, s->iface->addr->ip);
+#ifdef CONFIG_LINUX_MC_MREQ_BIND
+ {
+ struct ifreq ifr;
+ strcpy(ifr.ifr_name, s->iface->name);
+ if (setsockopt(s->fd, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr)) < 0)
+ return "SO_BINDTODEVICE";
+ mreq_add.imr_interface.s_addr = INADDR_ANY;
+ }
+#else
+ mreq_add.imr_interface = mreq;
+#endif
+ set_inaddr(&mreq_add.imr_multiaddr, s->daddr);
+ /* This defines where should we send _outgoing_ multicasts */
+ if (setsockopt(s->fd, SOL_IP, IP_MULTICAST_IF, &mreq, sizeof(mreq)) < 0)
+ return "IP_MULTICAST_IF";
+ /* And this one sets interface for _receiving_ multicasts from */
+ if (ipa_nonzero(s->saddr) && setsockopt(s->fd, SOL_IP, IP_ADD_MEMBERSHIP, &mreq_add, sizeof(mreq_add)) < 0)
+ return "IP_ADD_MEMBERSHIP";
+ return NULL;
+}
+#endif
+
+#endif