1 files changed, 377 insertions, 0 deletions
diff --git a/openbsd-compat/port-net.c b/openbsd-compat/port-net.c
new file mode 100644
index 0000000..d7d8c6f
--- /dev/null
+++ b/openbsd-compat/port-net.c
@@ -0,0 +1,377 @@
+/*
+ * Copyright (c) 2005 Reyk Floeter <reyk@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "includes.h"
+
+#include <sys/types.h>
+#include <sys/ioctl.h>
+
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <netinet/ip.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdarg.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "openbsd-compat/sys-queue.h"
+#include "log.h"
+#include "misc.h"
+#include "sshbuf.h"
+#include "channels.h"
+#include "ssherr.h"
+
+/*
+ * This file contains various portability code for network support,
+ * including tun/tap forwarding and routing domains.
+ */
+
+#if defined(SYS_RDOMAIN_LINUX) || defined(SSH_TUN_LINUX)
+#include <linux/if.h>
+#endif
+
+#if defined(SYS_RDOMAIN_LINUX)
+char *
+sys_get_rdomain(int fd)
+{
+	char dev[IFNAMSIZ + 1];
+	socklen_t len = sizeof(dev) - 1;
+
+	if (getsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, dev, &len) == -1) {
+		error("%s: cannot determine VRF for fd=%d : %s",
+		    __func__, fd, strerror(errno));
+		return NULL;
+	}
+	dev[len] = '\0';
+	return strdup(dev);
+}
+
+int
+sys_set_rdomain(int fd, const char *name)
+{
+	if (setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE,
+	    name, strlen(name)) == -1) {
+		error("%s: setsockopt(%d, SO_BINDTODEVICE, %s): %s",
+		      __func__, fd, name, strerror(errno));
+		return -1;
+	}
+	return 0;
+}
+
+int
+sys_valid_rdomain(const char *name)
+{
+	int fd;
+
+	/*
+	 * This is a pretty crappy way to test. It would be better to
+	 * check whether "name" represents a VRF device, but apparently
+	 * that requires an rtnetlink transaction.
+	 */
+	if ((fd = socket(AF_INET, SOCK_STREAM, 0)) == -1)
+		return 0;
+	if (setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE,
+	    name, strlen(name)) == -1) {
+		close(fd);
+		return 0;
+	}
+	close(fd);
+	return 1;
+}
+#elif defined(SYS_RDOMAIN_XXX)
+/* XXX examples */
+char *
+sys_get_rdomain(int fd)
+{
+	return NULL;
+}
+
+int
+sys_set_rdomain(int fd, const char *name)
+{
+	return -1;
+}
+
+int
+valid_rdomain(const char *name)
+{
+	return 0;
+}
+
+void
+sys_set_process_rdomain(const char *name)
+{
+	fatal("%s: not supported", __func__);
+}
+#endif /* defined(SYS_RDOMAIN_XXX) */
+
+/*
+ * This is the portable version of the SSH tunnel forwarding, it
+ * uses some preprocessor definitions for various platform-specific
+ * settings.
+ *
+ * SSH_TUN_LINUX	Use the (newer) Linux tun/tap device
+ * SSH_TUN_FREEBSD	Use the FreeBSD tun/tap device
+ * SSH_TUN_COMPAT_AF	Translate the OpenBSD address family
+ * SSH_TUN_PREPEND_AF	Prepend/remove the address family
+ */
+
+/*
+ * System-specific tunnel open function
+ */
+
+#if defined(SSH_TUN_LINUX)
+#include <linux/if_tun.h>
+#define TUN_CTRL_DEV "/dev/net/tun"
+
+int
+sys_tun_open(int tun, int mode, char **ifname)
+{
+	struct ifreq ifr;
+	int fd = -1;
+	const char *name = NULL;
+
+	if (ifname != NULL)
+		*ifname = NULL;
+	if ((fd = open(TUN_CTRL_DEV, O_RDWR)) == -1) {
+		debug("%s: failed to open tunnel control device \"%s\": %s",
+		    __func__, TUN_CTRL_DEV, strerror(errno));
+		return (-1);
+	}
+
+	bzero(&ifr, sizeof(ifr));
+
+	if (mode == SSH_TUNMODE_ETHERNET) {
+		ifr.ifr_flags = IFF_TAP;
+		name = "tap%d";
+	} else {
+		ifr.ifr_flags = IFF_TUN;
+		name = "tun%d";
+	}
+	ifr.ifr_flags |= IFF_NO_PI;
+
+	if (tun != SSH_TUNID_ANY) {
+		if (tun > SSH_TUNID_MAX) {
+			debug("%s: invalid tunnel id %x: %s", __func__,
+			    tun, strerror(errno));
+			goto failed;
+		}
+		snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), name, tun);
+	}
+
+	if (ioctl(fd, TUNSETIFF, &ifr) == -1) {
+		debug("%s: failed to configure tunnel (mode %d): %s", __func__,
+		    mode, strerror(errno));
+		goto failed;
+	}
+
+	if (tun == SSH_TUNID_ANY)
+		debug("%s: tunnel mode %d fd %d", __func__, mode, fd);
+	else
+		debug("%s: %s mode %d fd %d", __func__, ifr.ifr_name, mode, fd);
+
+	if (ifname != NULL && (*ifname = strdup(ifr.ifr_name)) == NULL)
+		goto failed;
+
+	return (fd);
+
+ failed:
+	close(fd);
+	return (-1);
+}
+#endif /* SSH_TUN_LINUX */
+
+#ifdef SSH_TUN_FREEBSD
+#include <sys/socket.h>
+#include <net/if.h>
+
+#ifdef HAVE_NET_IF_TUN_H
+#include <net/if_tun.h>
+#endif
+
+int
+sys_tun_open(int tun, int mode, char **ifname)
+{
+	struct ifreq ifr;
+	char name[100];
+	int fd = -1, sock;
+	const char *tunbase = "tun";
+#if defined(TUNSIFHEAD) && !defined(SSH_TUN_PREPEND_AF)
+	int flag;
+#endif
+
+	if (ifname != NULL)
+		*ifname = NULL;
+
+	if (mode == SSH_TUNMODE_ETHERNET) {
+#ifdef SSH_TUN_NO_L2
+		debug("%s: no layer 2 tunnelling support", __func__);
+		return (-1);
+#else
+		tunbase = "tap";
+#endif
+	}
+
+	/* Open the tunnel device */
+	if (tun <= SSH_TUNID_MAX) {
+		snprintf(name, sizeof(name), "/dev/%s%d", tunbase, tun);
+		fd = open(name, O_RDWR);
+	} else if (tun == SSH_TUNID_ANY) {
+		for (tun = 100; tun >= 0; tun--) {
+			snprintf(name, sizeof(name), "/dev/%s%d",
+			    tunbase, tun);
+			if ((fd = open(name, O_RDWR)) >= 0)
+				break;
+		}
+	} else {
+		debug("%s: invalid tunnel %u\n", __func__, tun);
+		return (-1);
+	}
+
+	if (fd < 0) {
+		debug("%s: %s open failed: %s", __func__, name,
+		    strerror(errno));
+		return (-1);
+	}
+
+	/* Turn on tunnel headers */
+#if defined(TUNSIFHEAD) && !defined(SSH_TUN_PREPEND_AF)
+	flag = 1;
+	if (mode != SSH_TUNMODE_ETHERNET &&
+	    ioctl(fd, TUNSIFHEAD, &flag) == -1) {
+		debug("%s: ioctl(%d, TUNSIFHEAD, 1): %s", __func__, fd,
+		    strerror(errno));
+		close(fd);
+	}
+#endif
+
+	debug("%s: %s mode %d fd %d", __func__, name, mode, fd);
+
+	/* Set the tunnel device operation mode */
+	snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s%d", tunbase, tun);
+	if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) == -1)
+		goto failed;
+
+	if (ioctl(sock, SIOCGIFFLAGS, &ifr) == -1)
+		goto failed;
+	if ((ifr.ifr_flags & IFF_UP) == 0) {
+		ifr.ifr_flags |= IFF_UP;
+		if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1)
+			goto failed;
+	}
+
+	if (ifname != NULL && (*ifname = strdup(ifr.ifr_name)) == NULL)
+		goto failed;
+
+	close(sock);
+	return (fd);
+
+ failed:
+	if (fd >= 0)
+		close(fd);
+	if (sock >= 0)
+		close(sock);
+	debug("%s: failed to set %s mode %d: %s", __func__, name,
+	    mode, strerror(errno));
+	return (-1);
+}
+#endif /* SSH_TUN_FREEBSD */
+
+/*
+ * System-specific channel filters
+ */
+
+#if defined(SSH_TUN_FILTER)
+/*
+ * The tunnel forwarding protocol prepends the address family of forwarded
+ * IP packets using OpenBSD's numbers.
+ */
+#define OPENBSD_AF_INET		2
+#define OPENBSD_AF_INET6	24
+
+int
+sys_tun_infilter(struct ssh *ssh, struct Channel *c, char *buf, int _len)
+{
+	int r;
+	size_t len;
+	char *ptr = buf;
+#if defined(SSH_TUN_PREPEND_AF)
+	char rbuf[CHAN_RBUF];
+	struct ip iph;
+#endif
+#if defined(SSH_TUN_PREPEND_AF) || defined(SSH_TUN_COMPAT_AF)
+	u_int32_t af;
+#endif
+
+	/* XXX update channel input filter API to use unsigned length */
+	if (_len < 0)
+		return -1;
+	len = _len;
+
+#if defined(SSH_TUN_PREPEND_AF)
+	if (len <= sizeof(iph) || len > sizeof(rbuf) - 4)
+		return -1;
+	/* Determine address family from packet IP header. */
+	memcpy(&iph, buf, sizeof(iph));
+	af = iph.ip_v == 6 ? OPENBSD_AF_INET6 : OPENBSD_AF_INET;
+	/* Prepend address family to packet using OpenBSD constants */
+	memcpy(rbuf + 4, buf, len);
+	len += 4;
+	POKE_U32(rbuf, af);
+	ptr = rbuf;
+#elif defined(SSH_TUN_COMPAT_AF)
+	/* Convert existing address family header to OpenBSD value */
+	if (len <= 4)
+		return -1;
+	af = PEEK_U32(buf);
+	/* Put it back */
+	POKE_U32(buf, af == AF_INET6 ? OPENBSD_AF_INET6 : OPENBSD_AF_INET);
+#endif
+
+	if ((r = sshbuf_put_string(c->input, ptr, len)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	return (0);
+}
+
+u_char *
+sys_tun_outfilter(struct ssh *ssh, struct Channel *c,
+    u_char **data, size_t *dlen)
+{
+	u_char *buf;
+	u_int32_t af;
+	int r;
+
+	/* XXX new API is incompatible with this signature. */
+	if ((r = sshbuf_get_string(c->output, data, dlen)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	if (*dlen < sizeof(af))
+		return (NULL);
+	buf = *data;
+
+#if defined(SSH_TUN_PREPEND_AF)
+	/* skip address family */
+	*dlen -= sizeof(af);
+	buf = *data + sizeof(af);
+#elif defined(SSH_TUN_COMPAT_AF)
+	/* translate address family */
+	af = (PEEK_U32(buf) == OPENBSD_AF_INET6) ? AF_INET6 : AF_INET;
+	POKE_U32(buf, af);
+#endif
+	return (buf);
+}
+#endif /* SSH_TUN_FILTER */