--- /dev/null
+/*
+ * 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 "log.h"
+#include "misc.h"
+#include "bufaux.h"
+
+/*
+ * 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_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.h>
+#include <linux/if_tun.h>
+
+int
+sys_tun_open(int tun, int mode)
+{
+ struct ifreq ifr;
+ int fd = -1;
+ const char *name = NULL;
+
+ if ((fd = open("/dev/net/tun", O_RDWR)) == -1) {
+ debug("%s: failed to open tunnel control interface: %s",
+ __func__, 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);
+
+ return (fd);
+
+ failed:
+ close(fd);
+ return (-1);
+}
+#endif /* SSH_TUN_LINUX */
+
+#ifdef SSH_TUN_FREEBSD
+#include <sys/socket.h>
+#include <net/if.h>
+#include <net/if_tun.h>
+
+int
+sys_tun_open(int tun, int mode)
+{
+ struct ifreq ifr;
+ char name[100];
+ int fd = -1, sock, flag;
+ const char *tunbase = "tun";
+
+ 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 */
+ flag = 1;
+#if defined(TUNSIFHEAD) && !defined(SSH_TUN_PREPEND_AF)
+ 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;
+ ifr.ifr_flags |= IFF_UP;
+ if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1)
+ 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)
+#define OPENBSD_AF_INET 2
+#define OPENBSD_AF_INET6 24
+
+int
+sys_tun_infilter(struct Channel *c, char *buf, int len)
+{
+#if defined(SSH_TUN_PREPEND_AF)
+ char rbuf[CHAN_RBUF];
+ struct ip *iph;
+#endif
+ u_int32_t *af;
+ char *ptr = buf;
+
+#if defined(SSH_TUN_PREPEND_AF)
+ if (len <= 0 || len > (int)(sizeof(rbuf) - sizeof(*af)))
+ return (-1);
+ ptr = (char *)&rbuf[0];
+ bcopy(buf, ptr + sizeof(u_int32_t), len);
+ len += sizeof(u_int32_t);
+ af = (u_int32_t *)ptr;
+
+ iph = (struct ip *)(ptr + sizeof(u_int32_t));
+ switch (iph->ip_v) {
+ case 6:
+ *af = AF_INET6;
+ break;
+ case 4:
+ default:
+ *af = AF_INET;
+ break;
+ }
+#endif
+
+#if defined(SSH_TUN_COMPAT_AF)
+ if (len < (int)sizeof(u_int32_t))
+ return (-1);
+
+ af = (u_int32_t *)ptr;
+ if (*af == htonl(AF_INET6))
+ *af = htonl(OPENBSD_AF_INET6);
+ else
+ *af = htonl(OPENBSD_AF_INET);
+#endif
+
+ buffer_put_string(&c->input, ptr, len);
+ return (0);
+}
+
+u_char *
+sys_tun_outfilter(struct Channel *c, u_char **data, u_int *dlen)
+{
+ u_char *buf;
+ u_int32_t *af;
+
+ *data = buffer_get_string(&c->output, dlen);
+ if (*dlen < sizeof(*af))
+ return (NULL);
+ buf = *data;
+
+#if defined(SSH_TUN_PREPEND_AF)
+ *dlen -= sizeof(u_int32_t);
+ buf = *data + sizeof(u_int32_t);
+#elif defined(SSH_TUN_COMPAT_AF)
+ af = ntohl(*(u_int32_t *)buf);
+ if (*af == OPENBSD_AF_INET6)
+ *af = htonl(AF_INET6);
+ else
+ *af = htonl(AF_INET);
+#endif
+
+ return (buf);
+}
+#endif /* SSH_TUN_FILTER */
andersk / gssapi-openssh.git / blobdiff