Update mud

.build.sh

@@ -0,0 +1,15 @@
+#!/bin/sh
+
+export CC="gcc -static"
+
+git clone https://github.com/jedisct1/libsodium --depth=1 --branch stable
+cd libsodium || exit 1
+./autogen.sh && ./configure --enable-minimal --disable-shared --prefix=/usr && make install
+cd ..
+
+./autogen.sh && ./configure && make
+[ -x glorytun ] || exit 1
+
+mkdir -p deploy
+strip -s glorytun
+mv glorytun deploy/glorytun-$(cat VERSION)-$(uname -m).bin

README.md

@@ -1,4 +1,4 @@
-# Glorytun
+# π₁(Glorytun)=ℤ²
 
 Small, Simple and Stupid VPN over [mud](https://github.com/angt/mud).
 

configure.ac

@@ -14,8 +14,9 @@ AM_SILENT_RULES([yes])
 AM_PROG_CC_C_O
 AC_PROG_CC_C99
 AC_USE_SYSTEM_EXTENSIONS
-AC_SEARCH_LIBS([getaddrinfo], [resolv nsl])
 AC_SEARCH_LIBS([socket], [socket])
+AC_CHECK_LIB([rt], [clock_gettime])
+AC_CHECK_FUNCS([clock_gettime])
 PKG_CHECK_MODULES([libsodium], [libsodium >= 1.0.4])
 AC_CONFIG_FILES([Makefile])
 AC_OUTPUT

src/ip.h

@@ -4,6 +4,7 @@
 
 struct ip_common {
     uint8_t version;
+    uint8_t tc;
     uint8_t proto;
     uint8_t hdr_size;
     uint16_t size;
@@ -24,11 +25,13 @@ static inline int ip_get_common (struct ip_common *ic, const uint8_t *data, size
 
     switch (ic->version) {
     case 4:
+        ic->tc = data[1];
         ic->proto = data[9];
         ic->hdr_size = (data[0]&0xF)<<2;
         ic->size = ((data[2]<<8)|data[3]);
         return 0;
     case 6:
+        ic->tc = ((data[0]&0xF)<<4)|(data[1]>>4);
         ic->proto = data[6];
         ic->hdr_size = 40;
         ic->size = ((data[4]<<8)|data[5])+40;

src/main.c

@@ -20,8 +20,6 @@
 #include <arpa/inet.h>
 #include <netdb.h>
 
-#include <sodium.h>
-
 #include "mud.h"
 
 #ifndef O_CLOEXEC
@@ -29,10 +27,10 @@
 #endif
 
 static struct {
-    int timeout;
     volatile sig_atomic_t quit;
     volatile sig_atomic_t info;
-    uint8_t key[crypto_generichash_KEYBYTES];
+    int timeout;
+    int state_fd;
 } gt;
 
 static void fd_set_nonblock (int fd)
@@ -185,16 +183,19 @@ static size_t fd_write_all (int fd, const void *data, size_t size)
     return done;
 }
 
-static int gt_setup_secretkey (char *keyfile)
+static int gt_setup_secretkey (struct mud *mud, char *keyfile)
 {
-    const size_t size = sizeof(gt.key);
+    unsigned char key[32];
 
     if (str_empty(keyfile)) {
-        char buf[2*size+1];
+        char buf[2*sizeof(key)+1];
+        size_t size = sizeof(key);
 
-        randombytes_buf(gt.key, size);
-        gt_tohex(buf, sizeof(buf), gt.key, size);
-        state("SECRETKEY", buf);
+        if (mud_get_key(mud, key, &size))
+            return -1;
+
+        gt_tohex(buf, sizeof(buf), key, size);
+        state_send(gt.state_fd, "SECRETKEY", buf);
 
         return 0;
     }
@@ -210,21 +211,23 @@ static int gt_setup_secretkey (char *keyfile)
         return -1;
     }
 
-    char key[2*size];
-    size_t r = fd_read_all(fd, key, sizeof(key));
+    char buf[2*sizeof(key)];
+    size_t r = fd_read_all(fd, buf, sizeof(buf));
 
     close(fd);
 
-    if (r!=sizeof(key)) {
+    if (r!=sizeof(buf)) {
         gt_log("unable to read secret key\n");
         return -1;
     }
 
-    if (gt_fromhex(gt.key, size, key, sizeof(key))) {
+    if (gt_fromhex(key, sizeof(key), buf, sizeof(buf))) {
         gt_log("secret key is not valid\n");
         return -1;
     }
 
+    mud_set_key(mud, key, sizeof(key));
+
     return 0;
 }
 
@@ -233,26 +236,44 @@ int main (int argc, char **argv)
     gt_set_signal();
 
     char *host = NULL;
-    char *port = "5000";
+    long port = 5000;
+
     char *bind_list = NULL;
-    char *bind_port = "5000";
+    long bind_port = 5000;
+
     char *dev = NULL;
     char *keyfile = NULL;
     char *statefile = NULL;
 
+    long mtu = 1450;
+
     gt.timeout = 5000;
 
+    long time_tolerance = 0;
+
+    int v4 = 1;
+    int v6 = 0;
+
+#ifdef __linux__
+    v6 = 1;
+#endif
+
     struct option opts[] = {
-        { "host",        &host,         option_str    },
-        { "port",        &port,         option_str    },
-        { "bind",        &bind_list,    option_str    },
-        { "bind-port",   &bind_port,    option_str    },
-        { "dev",         &dev,          option_str    },
-        { "keyfile",     &keyfile,      option_str    },
-        { "multiqueue",  NULL,          option_option },
-        { "statefile",   &statefile,    option_str    },
-        { "timeout",     &gt.timeout,   option_long   },
-        { "version",     NULL,          option_option },
+        { "host",           &host,           option_str    },
+        { "port",           &port,           option_long   },
+        { "bind",           &bind_list,      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   },
+        { "v4only",         NULL,            option_option },
+        { "v6only",         NULL,            option_option },
+        { "chacha20",       NULL,            option_option },
+        { "version",        NULL,            option_option },
         { NULL },
     };
 
@@ -264,7 +285,23 @@ int main (int argc, char **argv)
         return 0;
     }
 
-    if (!option_is_set(opts, "keyfile")) {
+    if (option_is_set(opts, "v4only")) {
+        v4 = 1;
+        v6 = 0;
+    }
+
+    if (option_is_set(opts, "v6only")) {
+        v4 = 0;
+        v6 = 1;
+    }
+
+    if (option_is_set(opts, "v4only") &&
+        option_is_set(opts, "v6only")) {
+        gt_log("v4only and v6only are both set\n");
+        return 1;
+    }
+
+    if (host && !option_is_set(opts, "keyfile")) {
         gt_log("keyfile option must be set\n");
         return 1;
     }
@@ -274,17 +311,9 @@ int main (int argc, char **argv)
         return 1;
     }
 
-    if (sodium_init()==-1) {
-        gt_log("libsodium initialization has failed\n");
-        return 1;
-    }
+    gt.state_fd = state_create(statefile);
 
-    if (!crypto_aead_aes256gcm_is_available()) {
-        gt_na("AES-256-GCM");
-        return 1;
-    }
-
-    if (state_init(statefile))
+    if (statefile && gt.state_fd==-1)
         return 1;
 
     char *tun_name = NULL;
@@ -296,21 +325,31 @@ int main (int argc, char **argv)
         return 1;
     }
 
+    if (tun_set_mtu(tun_name, mtu)==-1) {
+        perror("tun_set_mtu");
+        return 1;
+    }
+
     fd_set_nonblock(tun_fd);
 
-    if (gt_setup_secretkey(keyfile))
-        return 1;
+    int chacha = option_is_set(opts, "chacha20");
 
-    struct mud *mud = mud_create(bind_port);
+    struct mud *mud = mud_create(bind_port, v4, v6, !chacha, mtu);
 
     if (!mud) {
         gt_log("couldn't create mud\n");
         return 1;
     }
 
-    mud_set_key(mud, gt.key, sizeof(gt.key));
+    if (gt_setup_secretkey(mud, keyfile))
+        return 1;
 
-    if (bind_list) {
+    mud_set_send_timeout_msec(mud, gt.timeout);
+
+    if (time_tolerance > 0)
+        mud_set_time_tolerance_sec(mud, time_tolerance);
+
+    if (host && port && bind_list) {
         char tmp[1024];
         char *name = &tmp[0];
 
@@ -322,28 +361,36 @@ int main (int argc, char **argv)
 
             tmp[i] = 0;
 
-            if (mud_bind(mud, name))
+            if (mud_peer(mud, name, host, port))
                 return 1;
 
             name = &tmp[i+1];
         }
 
-        if (name[0] && mud_bind(mud, name))
+        if (name[0] && mud_peer(mud, name, host, port))
             return 1;
     }
 
-    if (host && mud_peer(mud, host, port))
-        return 1;
-
     int mud_fd = mud_get_fd(mud);
 
-    state("INITIALIZED", tun_name);
+    state_send(gt.state_fd, "INITIALIZED", tun_name);
 
     fd_set rfds;
     FD_ZERO(&rfds);
 
     int started = 0;
-    unsigned char buf[2048];
+
+    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;
 
     while (!gt.quit) {
         FD_SET(tun_fd, &rfds);
@@ -355,9 +402,12 @@ int main (int argc, char **argv)
         }
 
         struct timeval timeout = {
-            .tv_usec = 1000,
+            .tv_usec = 100000,
         };
 
+        if (mud_can_push(mud) || send_size)
+            timeout.tv_usec = 1000;
+
         if _0_(select(mud_fd+1, &rfds, NULL, NULL, &timeout)==-1) {
             if (errno==EINTR)
                 continue;
@@ -367,40 +417,133 @@ int main (int argc, char **argv)
 
         if (mud_is_up(mud)) {
             if (!started) {
-                state("STARTED", NULL);
+                state_send(gt.state_fd, "STARTED", tun_name);
                 started = 1;
             }
-        } else if (started) {
-            state("STOPPED", NULL);
-            started = 0;
+        } else {
+            if (started) {
+                state_send(gt.state_fd, "STOPPED", tun_name);
+                started = 0;
+            }
         }
 
         if (FD_ISSET(tun_fd, &rfds)) {
-            while (1) {
-                const ssize_t r = tun_read(tun_fd, buf, sizeof(buf));
+            while (send_size<mtu) {
+                const ssize_t r = tun_read(tun_fd, send.buf+send_size, mtu);
 
-                if (r<=0)
+                if (r<=0) {
+                    gt.quit |= !r;
                     break;
+                }
 
                 struct ip_common ic;
 
-                if (!ip_get_common(&ic, buf, sizeof(buf)) && ic.size==r)
-                    mud_send(mud, buf, r);
+                if (ip_get_common(&ic, send.buf+send_size, mtu) || ic.size!=r) {
+                    gt_log("packet dropped: malformed\n");
+                    continue;
+                }
+
+                send_size += r;
+
+                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;
+                }
             }
         }
 
-        mud_push(mud);
+        if (send_limit) {
+            int r = mud_send(mud, send.buf, send_limit, send_tc);
 
-        if (FD_ISSET(mud_fd, &rfds))
-            mud_pull(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;
 
-        while (1) {
-            const int r = mud_recv(mud, buf, sizeof(buf));
+                        if (tun_set_mtu(tun_name, new_mtu)==-1) {
+                            perror("tun_set_mtu");
+                            gt.quit |= 1;
+                            break;
+                        }
 
-            if (r<=0)
+                        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;
+
+                            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;
+                            } else {
+                                if ((ic.tc&0xFC)>(send_next_tc&0xFC))
+                                    send_next_tc = ic.tc;
+                            }
+                        }
+                    }
+                } else if (errno!=EAGAIN) {
+                    perror("mud_send");
+                }
+            }
+        }
+
+        if (mud_push(mud)==-1 && errno!=EAGAIN)
+            perror("mud_push");
+
+        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);
+
+            if (size<=0) {
+                if (size==-1 && errno!=EAGAIN)
+                    perror("mud_recv");
                 break;
+            }
 
-            tun_write(tun_fd, buf, r);
+            int p = 0;
+
+            while (p<size) {
+                struct ip_common ic;
+
+                if (ip_get_common(&ic, recv.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;
+                }
+
+                p += ic.size;
+            }
         }
     }
 

src/state.c

@@ -7,16 +7,14 @@
 #include <fcntl.h>
 #include <sys/stat.h>
 
-static int state_fd = -1;
-
-int state_init (const char *filename)
+int state_create (const char *filename)
 {
     if (str_empty(filename))
-        return 0;
+        return -1;
 
-    state_fd = open(filename, O_WRONLY);
+    int fd = open(filename, O_WRONLY);
 
-    if (state_fd==-1) {
+    if (fd==-1) {
         if (errno!=EINTR)
             perror("open");
         return -1;
@@ -24,38 +22,41 @@ int state_init (const char *filename)
 
     struct stat st = {0};
 
-    if (fstat(state_fd, &st)==-1) {
+    if (fstat(fd, &st)==-1) {
         perror("fstat");
-        close(state_fd);
-        state_fd = -1;
+        close(fd);
         return -1;
     }
 
     if (!S_ISFIFO(st.st_mode)) {
         gt_log("`%s' is not a fifo\n", filename);
-        close(state_fd);
-        state_fd = -1;
+        close(fd);
         return -1;
     }
 
-    return 0;
+    return fd;
 }
 
-void state (const char *state, const char *info)
+void state_send (int fd, const char *state, const char *info)
 {
     if (str_empty(state))
         return;
 
+    if (fd==-1) {
+        gt_print("%s %s\n", state, info);
+        return;
+    }
+
     const char *strs[] = { state, " ", info, "\n" };
     char *str = str_cat(strs, COUNT(strs));
 
-    if (!str)
+    if (!str) {
+        perror("str_cat");
         return;
-
-    if (state_fd==-1) {
-        gt_print("%s", str);
-    } else {
-        if (write(state_fd, str, str_len(str))==-1 && errno!=EINTR)
-            perror("write");
     }
+
+    if (write(fd, str, str_len(str))==-1 && errno!=EINTR)
+        perror("write");
+
+    free(str);
 }

src/state.h

@@ -1,4 +1,4 @@
 #pragma once
 
-int  state_init (const char *);
-void state      (const char *, const char *);
+int  state_create (const char *);
+void state_send   (int, const char *, const char *);

src/tun.c

@@ -240,3 +240,25 @@ ssize_t tun_write (int fd, const void *data, size_t size)
     return ret;
 #endif
 }
+
+int tun_set_mtu (char *dev_name, int mtu)
+{
+    struct ifreq ifr = {
+        .ifr_mtu = mtu,
+    };
+
+    str_cpy(ifr.ifr_name, dev_name, IFNAMSIZ-1);
+
+    int fd = socket(AF_INET, SOCK_DGRAM, 0);
+
+    if (fd==-1)
+        return -1;
+
+    int ret = ioctl(fd, SIOCSIFMTU, &ifr);
+
+    int err = errno;
+    close(fd);
+    errno = err;
+
+    return ret;
+}

src/tun.h

@@ -2,6 +2,7 @@
 
 #include <unistd.h>
 
-int     tun_create (char *, char **, int);
-ssize_t tun_read   (int, void *, size_t);
-ssize_t tun_write  (int, const void *, size_t);
+int     tun_create  (char *, char **, int);
+ssize_t tun_read    (int, void *, size_t);
+ssize_t tun_write   (int, const void *, size_t);
+int     tun_set_mtu (char *, int);