Add bind-backup option

Required on BSD. Doesn't break anything elsewhere.

src/main.c

@@ -239,6 +239,7 @@ int main (int argc, char **argv)
     long port = 5000;
 
     char *bind_list = NULL;
+    char *bind_backup = NULL;
     long bind_port = 5000;
 
     char *dev = NULL;
@@ -262,11 +263,11 @@ int main (int argc, char **argv)
         { "host",           &host,           option_str    },
         { "port",           &port,           option_long   },
         { "bind",           &bind_list,      option_str    },
+        { "bind-backup",    &bind_backup,    option_str    },
         { "bind-port",      &bind_port,      option_long   },
         { "dev",            &dev,            option_str    },
         { "mtu",            &mtu,            option_long   },
         { "keyfile",        &keyfile,        option_str    },
-        { "multiqueue",     NULL,            option_option },
         { "statefile",      &statefile,      option_str    },
         { "timeout",        &gt.timeout,     option_long   },
         { "time-tolerance", &time_tolerance, option_long   },
@@ -311,6 +312,15 @@ int main (int argc, char **argv)
         return 1;
     }
 
+    int icmp_fd = -1;
+
+    if (v4) {
+        icmp_fd = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP);
+
+        if (icmp_fd==-1)
+            gt_log("couldn't create ICMP socket\n");
+    }
+
     gt.state_fd = state_create(statefile);
 
     if (statefile && gt.state_fd==-1)
@@ -318,7 +328,7 @@ int main (int argc, char **argv)
 
     char *tun_name = NULL;
 
-    int tun_fd = tun_create(dev, &tun_name, option_is_set(opts, "multiqueue"));
+    int tun_fd = tun_create(dev, &tun_name);
 
     if (tun_fd==-1) {
         gt_log("couldn't create tun device\n");
@@ -349,177 +359,148 @@ int main (int argc, char **argv)
     if (time_tolerance > 0)
         mud_set_time_tolerance_sec(mud, time_tolerance);
 
-    if (host && port && bind_list) {
+    if (host && port) {
+        if (bind_backup) {
+            if (mud_peer(mud, bind_backup, host, port, 1)) {
+                perror("mud_peer (backup)");
+                return 1;
+            }
+        }
+
+        if (bind_list) {
             char tmp[1024];
             char *name = &tmp[0];
 
-        size_t size = str_cpy(tmp, bind_list, sizeof(tmp)-1);
+            str_cpy(tmp, bind_list, sizeof(tmp)-1);
 
-        for (size_t i=0; i<size; i++) {
-            if (tmp[i]!=',')
-                continue;
+            while (*name) {
+                char *p = name;
 
-            tmp[i] = 0;
+                while (*p && *p!=',')
+                    p++;
 
-            if (mud_peer(mud, name, host, port))
+                if (*p)
+                    *p++ = 0;
+
+                if (mud_peer(mud, name, host, port, 0)) {
+                    perror("mud_peer");
                     return 1;
-
-            name = &tmp[i+1];
                 }
 
-        if (name[0] && mud_peer(mud, name, host, port))
-            return 1;
+                name = p;
+            }
+        }
     }
 
     int mud_fd = mud_get_fd(mud);
 
+    fd_set_nonblock(mud_fd);
+
     state_send(gt.state_fd, "INITIALIZED", tun_name);
 
     fd_set rfds;
     FD_ZERO(&rfds);
 
-    int started = 0;
-
-    struct {
-        unsigned char *buf;
-    } send, recv;
-
-    send.buf = malloc(2*mtu);
-    recv.buf = malloc(mtu);
-
-    size_t send_size = 0;
-    size_t send_limit = 0;
-    int send_tc = 0;
-    int send_next_tc = 0;
+    unsigned char buf[8*1024];
 
     while (!gt.quit) {
         FD_SET(tun_fd, &rfds);
-
-        if (mud_can_pull(mud)) {
         FD_SET(mud_fd, &rfds);
-        } else {
-            FD_CLR(mud_fd, &rfds);
-        }
 
-        struct timeval timeout = {
-            .tv_usec = 100000,
-        };
+        if (icmp_fd!=-1)
+            FD_SET(icmp_fd, &rfds);
 
-        if (mud_can_push(mud) || send_size)
-            timeout.tv_usec = 1000;
-
-        if _0_(select(mud_fd+1, &rfds, NULL, NULL, &timeout)==-1) {
+        if _0_(select(mud_fd+1, &rfds, NULL, NULL, NULL)==-1) {
             if (errno==EINTR)
                 continue;
             perror("select");
             return 1;
         }
 
-        if (mud_is_up(mud)) {
-            if (!started) {
-                state_send(gt.state_fd, "STARTED", tun_name);
-                started = 1;
+        if (icmp_fd!=-1 && FD_ISSET(icmp_fd, &rfds)) {
+            struct sockaddr_storage ss;
+            socklen_t sl = sizeof(ss);
+            ssize_t r = recvfrom(icmp_fd, buf, sizeof(buf), 0, (struct sockaddr *)&ss, &sl);
+            if (r>=8) {
+                struct ip_common ic;
+                if (!ip_get_common(&ic, buf, r) && ic.proto==1) {
+                    unsigned char *data = &buf[ic.hdr_size];
+                    if (data[0]==3) {
+                        int new_mtu = (data[6]<<8)|data[7];
+                        if (new_mtu) {
+                            gt_log("received MTU from ICMP: %i\n", new_mtu);
+                            mud_set_mtu(mud, new_mtu-50); // XXX
+                        }
+                    }
                 }
-        } else {
-            if (started) {
-                state_send(gt.state_fd, "STOPPED", tun_name);
-                started = 0;
             }
         }
 
         if (FD_ISSET(tun_fd, &rfds)) {
-            while (send_size<mtu) {
-                const ssize_t r = tun_read(tun_fd, send.buf+send_size, mtu);
+            size_t size = 0;
 
-                if (r<=0) {
-                    gt.quit |= !r;
+            while (sizeof(buf)-size>mtu) {
+                const ssize_t r = tun_read(tun_fd, &buf[size], sizeof(buf)-size);
+
+                if (r<=0)
                     break;
-                }
 
                 struct ip_common ic;
 
-                if (ip_get_common(&ic, send.buf+send_size, mtu) || ic.size!=r) {
-                    gt_log("packet dropped: malformed\n");
-                    continue;
+                if (ip_get_common(&ic, &buf[size], r) || ic.size!=r)
+                    break;
+
+                size += r;
             }
 
-                send_size += r;
+            int p = 0;
 
-                if (send_size<=mtu) {
-                    send_limit = send_size;
-                    if ((ic.tc&0xFC)>(send_tc&0xFC))
-                        send_tc = ic.tc;
-                } else {
-                    if ((ic.tc&0xFC)>(send_next_tc&0xFC))
-                        send_next_tc = ic.tc;
-                }
-            }
+            while (p<size) {
+                int tc = 0;
+                int q = p;
+
+                while (q<size) {
+                    struct ip_common ic;
+
+                    if (ip_get_common(&ic, &buf[q], size-q) || ic.size>size-q) {
+                        size = q;
+                        break;
                     }
 
-        if (send_limit) {
-            int r = mud_send(mud, send.buf, send_limit, send_tc);
+                    if (q+ic.size>p+mtu)
+                        break;
+
+                    q += ic.size;
+
+                    if (tc<(ic.tc&0xFC))
+                        tc = ic.tc&0xFC;
+                }
+
+                int r = mud_send(mud, &buf[p], q-p, tc);
+
+                if (r==-1 && errno==EMSGSIZE) {
+                    int new_mtu = mud_get_mtu(mud);
 
-            if (r==send_limit) {
-                if (send_size>send_limit)
-                    memmove(send.buf, &send.buf[send_limit], send_size-send_limit);
-                send_size -= send_limit;
-                send_limit = send_size;
-                send_tc = send_next_tc;
-                send_next_tc = 0;
-            } else if (r==-1) {
-                if (errno==EMSGSIZE) {
-                    long new_mtu = mud_get_mtu(mud);
                     if (new_mtu!=mtu) {
-                        size_t total = send_size;
-
-                        if (tun_set_mtu(tun_name, new_mtu)==-1) {
-                            perror("tun_set_mtu");
-                            gt.quit |= 1;
-                            break;
-                        }
-
-                        gt_log("MTU changed: %li\n", new_mtu);
-
                         mtu = new_mtu;
-                        send_size = 0;
-                        send_limit = 0;
-                        send_tc = 0;
-                        send_next_tc = 0;
 
-                        while (send_size<total) {
-                            struct ip_common ic;
+                        gt_log("MTU changed: %li\n", mtu);
 
-                            if (ip_get_common(&ic, send.buf+send_size, mtu))
-                                break;
-
-                            send_size += ic.size;
-
-                            if (send_size<=mtu) {
-                                send_limit = send_size;
-                                if ((ic.tc&0xFC)>(send_tc&0xFC))
-                                    send_tc = ic.tc;
+                        if (tun_set_mtu(tun_name, mtu)==-1)
+                            perror("tun_set_mtu");
+                    }
                 } else {
-                                if ((ic.tc&0xFC)>(send_next_tc&0xFC))
-                                    send_next_tc = ic.tc;
-                            }
-                        }
-                    }
-                } else if (errno!=EAGAIN) {
+                    if (r==-1 && errno!=EAGAIN)
                         perror("mud_send");
-                }
-            }
-        }
 
-        if (mud_push(mud)==-1 && errno!=EAGAIN)
-            perror("mud_push");
+                    p = q;
+                }
+            }
+        }
 
         if (FD_ISSET(mud_fd, &rfds)) {
-            if (mud_pull(mud)==-1 && errno!=EAGAIN)
-                perror("mud_pull");
-        }
-
-        while (!gt.quit) {
-            const int size = mud_recv(mud, recv.buf, mtu);
+            while (1) {
+                const int size = mud_recv(mud, buf, sizeof(buf));
 
                 if (size<=0) {
                     if (size==-1 && errno!=EAGAIN)
@@ -532,20 +513,16 @@ int main (int argc, char **argv)
                 while (p<size) {
                     struct ip_common ic;
 
-                if (ip_get_common(&ic, recv.buf+p, size-p) || ic.size>size-p)
+                    if (ip_get_common(&ic, &buf[p], size-p) || ic.size>size-p)
                         break;
 
-                const ssize_t r = tun_write(tun_fd, recv.buf+p, ic.size);
-
-                if (r<=0) {
-                    gt.quit |= !r;
-                    break;
-                }
+                    tun_write(tun_fd, &buf[p], ic.size);
 
                     p += ic.size;
                 }
             }
         }
+    }
 
     return 0;
 }

src/tun.c

@@ -11,8 +11,9 @@
 #include <sys/socket.h>
 #include <sys/uio.h>
 
+#include <net/if.h>
+
 #ifdef __linux__
-#include <linux/if.h>
 #include <linux/if_tun.h>
 #endif
 
@@ -28,7 +29,7 @@
 
 #ifdef __APPLE__
 
-static int tun_create_by_id (char *name, size_t size, unsigned id, _unused_ int mq)
+static int tun_create_by_id (char *name, size_t size, unsigned id)
 {
     int fd = socket(PF_SYSTEM, SOCK_DGRAM, SYSPROTO_CONTROL);
 
@@ -63,21 +64,21 @@ static int tun_create_by_id (char *name, size_t size, unsigned id, _unused_ int
     return fd;
 }
 
-static int tun_create_by_name (char *name, size_t size, char *dev_name, int mq)
+static int tun_create_by_name (char *name, size_t size, char *dev_name)
 {
     unsigned id = 0;
 
     if (sscanf(dev_name, "utun%u", &id)!=1)
         return -1;
 
-    return tun_create_by_id(name, size, id, mq);
+    return tun_create_by_id(name, size, id);
 }
 
 #else /* not __APPLE__ */
 
 #ifdef __linux__
 
-static int tun_create_by_name (char *name, size_t size, char *dev_name, int mq)
+static int tun_create_by_name (char *name, size_t size, char *dev_name)
 {
     int fd = open("/dev/net/tun", O_RDWR);
 
@@ -88,12 +89,6 @@ static int tun_create_by_name (char *name, size_t size, char *dev_name, int mq)
         .ifr_flags = IFF_TUN|IFF_NO_PI,
     };
 
-    if (mq) {
-#ifdef IFF_MULTI_QUEUE
-        ifr.ifr_flags |= IFF_MULTI_QUEUE;
-#endif
-    }
-
     str_cpy(ifr.ifr_name, dev_name, IFNAMSIZ-1);
 
     if (ioctl(fd, TUNSETIFF, &ifr)) {
@@ -108,7 +103,7 @@ static int tun_create_by_name (char *name, size_t size, char *dev_name, int mq)
 
 #else /* not __linux__ not __APPLE__ */
 
-static int tun_create_by_name (char *name, size_t size, char *dev_name, _unused_ int mq)
+static int tun_create_by_name (char *name, size_t size, char *dev_name)
 {
     char path[64];
 
@@ -120,32 +115,27 @@ static int tun_create_by_name (char *name, size_t size, char *dev_name, _unused_
 
 #endif /* not __APPLE__ */
 
-static int tun_create_by_id (char *name, size_t size, unsigned id, int mq)
+static int tun_create_by_id (char *name, size_t size, unsigned id)
 {
     char dev_name[64];
 
     snprintf(dev_name, sizeof(dev_name), "tun%u", id);
 
-    return tun_create_by_name(name, size, dev_name, mq);
+    return tun_create_by_name(name, size, dev_name);
 }
 
 #endif
 
-int tun_create (char *dev_name, char **ret_name, int mq)
+int tun_create (char *dev_name, char **ret_name)
 {
     char name[64] = {0};
     int fd = -1;
 
-#ifndef IFF_MULTI_QUEUE
-    if (mq)
-        gt_na("IFF_MULTI_QUEUE");
-#endif
-
     if (str_empty(dev_name)) {
         for (unsigned id=0; id<32 && fd==-1; id++)
-            fd = tun_create_by_id(name, sizeof(name), id, mq);
+            fd = tun_create_by_id(name, sizeof(name), id);
     } else {
-        fd = tun_create_by_name(name, sizeof(name), dev_name, mq);
+        fd = tun_create_by_name(name, sizeof(name), dev_name);
     }
 
     if (fd!=-1 && ret_name)

src/tun.h

@@ -2,7 +2,7 @@
 
 #include <unistd.h>
 
-int     tun_create  (char *, char **, int);
+int     tun_create  (char *, char **);
 ssize_t tun_read    (int, void *, size_t);
 ssize_t tun_write   (int, const void *, size_t);
 int     tun_set_mtu (char *, int);