1 files changed, 169 insertions, 4 deletions

diff --git a/misc.c b/misc.c
index 2dd8ae6e3..29e928886 100644
--- a/misc.c
+++ b/misc.c
@@ -24,7 +24,11 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: misc.c,v 1.34 2005/07/08 09:26:18 dtucker Exp $");
+RCSID("$OpenBSD: misc.c,v 1.42 2006/01/31 10:19:02 djm Exp $");
+
+#ifdef SSH_TUN_OPENBSD
+#include <net/if.h>
+#endif
 
 #include "misc.h"
 #include "log.h"
@@ -194,6 +198,37 @@ a2port(const char *s)
         return port;
 }
 
+int
+a2tun(const char *s, int *remote)
+{
+        const char *errstr = NULL;
+        char *sp, *ep;
+        int tun;
+
+        if (remote != NULL) {
+                *remote = SSH_TUNID_ANY;
+                sp = xstrdup(s);
+                if ((ep = strchr(sp, ':')) == NULL) {
+                        xfree(sp);
+                        return (a2tun(s, NULL));
+                }
+                ep[0] = '\0'; ep++;
+                *remote = a2tun(ep, NULL);
+                tun = a2tun(sp, NULL);
+                xfree(sp);
+                return (*remote == SSH_TUNID_ERR ? *remote : tun);
+        }
+
+        if (strcasecmp(s, "any") == 0)
+                return (SSH_TUNID_ANY);
+
+        tun = strtonum(s, 0, SSH_TUNID_MAX, &errstr);
+        if (errstr != NULL)
+                return (SSH_TUNID_ERR);
+
+        return (tun);
+}
+
 #define SECONDS         1
 #define MINUTES         (SECONDS * 60)
 #define HOURS           (MINUTES * 60)
@@ -356,12 +391,15 @@ void
 addargs(arglist *args, char *fmt, ...)
 {
         va_list ap;
-        char buf[1024];
+        char *cp;
         u_int nalloc;
+        int r;
 
         va_start(ap, fmt);
-        vsnprintf(buf, sizeof(buf), fmt, ap);
+        r = vasprintf(&cp, fmt, ap);
         va_end(ap);
+        if (r == -1)
+                fatal("addargs: argument too long");
 
         nalloc = args->nalloc;
         if (args->list == NULL) {
@@ -372,10 +410,44 @@ addargs(arglist *args, char *fmt, ...)
 
         args->list = xrealloc(args->list, nalloc * sizeof(char *));
         args->nalloc = nalloc;
-        args->list[args->num++] = xstrdup(buf);
+        args->list[args->num++] = cp;
         args->list[args->num] = NULL;
 }
 
+void
+replacearg(arglist *args, u_int which, char *fmt, ...)
+{
+        va_list ap;
+        char *cp;
+        int r;
+
+        va_start(ap, fmt);
+        r = vasprintf(&cp, fmt, ap);
+        va_end(ap);
+        if (r == -1)
+                fatal("replacearg: argument too long");
+
+        if (which >= args->num)
+                fatal("replacearg: tried to replace invalid arg %d >= %d",
+                    which, args->num);
+        xfree(args->list[which]);
+        args->list[which] = cp;
+}
+
+void
+freeargs(arglist *args)
+{
+        u_int i;
+
+        if (args->list != NULL) {
+                for (i = 0; i < args->num; i++)
+                        xfree(args->list[i]);
+                xfree(args->list);
+                args->nalloc = args->num = 0;
+                args->list = NULL;
+        }
+}
+
 /*
  * Expands tildes in the file name.  Returns data allocated by xmalloc.
  * Warning: this calls getpw*.
@@ -507,6 +579,99 @@ read_keyfile_line(FILE *f, const char *filename, char *buf, size_t bufsz,
         return -1;
 }
 
+int
+tun_open(int tun, int mode)
+{
+#if defined(CUSTOM_SYS_TUN_OPEN)
+        return (sys_tun_open(tun, mode));
+#elif defined(SSH_TUN_OPENBSD)
+        struct ifreq ifr;
+        char name[100];
+        int fd = -1, sock;
+
+        /* Open the tunnel device */
+        if (tun <= SSH_TUNID_MAX) {
+                snprintf(name, sizeof(name), "/dev/tun%d", tun);
+                fd = open(name, O_RDWR);
+        } else if (tun == SSH_TUNID_ANY) {
+                for (tun = 100; tun >= 0; tun--) {
+                        snprintf(name, sizeof(name), "/dev/tun%d", tun);
+                        if ((fd = open(name, O_RDWR)) >= 0)
+                                break;
+                }
+        } else {
+                debug("%s: invalid tunnel %u", __func__, tun);
+                return (-1);
+        }
+
+        if (fd < 0) {
+                debug("%s: %s open failed: %s", __func__, name, strerror(errno));
+                return (-1);
+        }
+
+        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), "tun%d", tun);
+        if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) == -1)
+                goto failed;
+
+        if (ioctl(sock, SIOCGIFFLAGS, &ifr) == -1)
+                goto failed;
+
+        /* Set interface mode */
+        ifr.ifr_flags &= ~IFF_UP;
+        if (mode == SSH_TUNMODE_ETHERNET)
+                ifr.ifr_flags |= IFF_LINK0;
+        else
+                ifr.ifr_flags &= ~IFF_LINK0;
+        if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1)
+                goto failed;
+
+        /* Bring interface up */
+        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);
+#else
+        error("Tunnel interfaces are not supported on this platform");
+        return (-1);
+#endif
+}
+
+void
+sanitise_stdfd(void)
+{
+        int nullfd, dupfd;
+
+        if ((nullfd = dupfd = open(_PATH_DEVNULL, O_RDWR)) == -1) {
+                fprintf(stderr, "Couldn't open /dev/null: %s", strerror(errno));
+                exit(1);
+        }
+        while (++dupfd <= 2) {
+                /* Only clobber closed fds */
+                if (fcntl(dupfd, F_GETFL, 0) >= 0)
+                        continue;
+                if (dup2(nullfd, dupfd) == -1) {
+                        fprintf(stderr, "dup2: %s", strerror(errno));
+                        exit(1);
+                }
+        }
+        if (nullfd > 2)
+                close(nullfd);
+}
+
 char *
 tohex(const u_char *d, u_int l)
 {