Improve error messages

Signed-off-by: Adrien Gallouët <adrien@gallouet.fr>

src/bind.c

@@ -18,13 +18,13 @@
 #define O_CLOEXEC 0
 #endif
 
-static void
+static int
 fd_set_nonblock(int fd)
 {
-    int ret;
-
     if (fd == -1)
-        return;
+        return 0;
+
+    int ret;
 
     do {
         ret = fcntl(fd, F_GETFL, 0);
@@ -36,8 +36,7 @@ fd_set_nonblock(int fd)
         ret = fcntl(fd, F_SETFL, flags | O_NONBLOCK);
     } while (ret == -1 && errno == EINTR);
 
-    if (ret == -1)
-        perror("fcntl O_NONBLOCK");
+    return ret;
 }
 
 static int
@@ -50,7 +49,7 @@ gt_setup_secretkey(struct mud *mud, const char *keyfile)
     } while (fd == -1 && errno == EINTR);
 
     if (fd == -1) {
-        perror("open keyfile");
+        gt_log("couldn't open %s: %s\n", keyfile, strerror(errno));
         return -1;
     }
 
@@ -73,7 +72,7 @@ gt_setup_secretkey(struct mud *mud, const char *keyfile)
     close(fd);
 
     if (size != sizeof(buf)) {
-        gt_log("unable to read secret key\n");
+        gt_log("couldn't read secret key\n");
         return -1;
     }
 
@@ -96,7 +95,7 @@ gt_setup_mtu(struct mud *mud, size_t old, const char *tun_name)
         return mtu;
 
     if (iface_set_mtu(tun_name, mtu) == -1)
-        perror("tun_set_mtu");
+        gt_log("couldn't setup MTU at %zu on device %s\n", mtu, tun_name);
 
     return mtu;
 }
@@ -165,7 +164,7 @@ gt_bind(int argc, char **argv)
     }
 
     char tun_name[64];
-    const int tun_fd = tun_create(tun_name, sizeof(tun_name) - 1, dev);
+    const int tun_fd = tun_create(tun_name, sizeof(tun_name), dev);
 
     if (tun_fd == -1) {
         gt_log("couldn't create tun device\n");
@@ -174,8 +173,10 @@ gt_bind(int argc, char **argv)
 
     size_t mtu = gt_setup_mtu(mud, 0, tun_name);
 
-    if (tun_set_persist(tun_fd, persist) == -1)
-        perror("tun_set_persist");
+    if (tun_set_persist(tun_fd, persist) == -1) {
+        gt_log("couldn't %sable persist mode on device %s\n",
+                persist ? "en" : "dis", tun_name);
+    }
 
     if (peer_addr.ss_family) {
         if (mud_peer(mud, (struct sockaddr *)&peer_addr)) {
@@ -187,13 +188,17 @@ gt_bind(int argc, char **argv)
     const int ctl_fd = ctl_create(GT_RUNDIR, tun_name);
 
     if (ctl_fd == -1) {
-        perror("ctl_create");
+        gt_log("couldn't create "GT_RUNDIR"/%s: %s\n",
+                tun_name, strerror(errno));
         return 1;
     }
 
-    fd_set_nonblock(tun_fd);
-    fd_set_nonblock(mud_fd);
-    fd_set_nonblock(ctl_fd);
+    if (fd_set_nonblock(tun_fd) ||
+        fd_set_nonblock(mud_fd) ||
+        fd_set_nonblock(ctl_fd)) {
+        gt_log("couldn't setup non-blocking fds\n");
+        return 1;
+    }
 
     const long pid = (long)getpid();
 
@@ -309,11 +314,18 @@ gt_bind(int argc, char **argv)
             }
         }
 
-        if (FD_ISSET(mud_fd, &rfds)) {
-            const int r = mud_recv(mud, buf, sizeof(buf));
+        if (FD_ISSET(mud_fd, &rfds))  {
+            int n = 1000;
 
-            if (r > 0 && ip_is_valid(buf, r))
-                tun_write(tun_fd, buf, (size_t)r);
+            while (n--) {
+                const int r = mud_recv(mud, buf, sizeof(buf));
+
+                if (r <= 0)
+                    break;
+
+                if (ip_is_valid(buf, r))
+                    tun_write(tun_fd, buf, (size_t)r);
+            }
         }
 
         if (FD_ISSET(tun_fd, &rfds) && !mud_send_wait(mud)) {
@@ -333,10 +345,8 @@ gt_bind(int argc, char **argv)
         }
     }
 
-    if (gt_reload && tun_fd >= 0) {
-        if (tun_set_persist(tun_fd, 1) == -1)
-            perror("tun_set_persist");
-    }
+    if (gt_reload && tun_fd >= 0)
+        tun_set_persist(tun_fd, 1);
 
     mud_delete(mud);
     ctl_delete(ctl_fd);

src/ctl.c

@@ -2,6 +2,7 @@
 #include "ctl.h"
 #include "str.h"
 
+#include <stdio.h>
 #include <unistd.h>
 #include <dirent.h>
 #include <sys/socket.h>
@@ -22,7 +23,7 @@ ctl_reply(int fd, struct ctl_msg *res, struct ctl_msg *req)
         return -1;
 
     if (res->type != req->type || !res->reply) {
-        errno = EINTR;
+        errno = EINVAL;
         return -1;
     }
 
@@ -41,17 +42,15 @@ ctl_setsun(struct sockaddr_un *dst, const char *dir, const char *file)
         .sun_family = AF_UNIX,
     };
 
-    const char *path[] = {dir, "/", file};
-    const size_t len = sizeof(sun.sun_path) - 1;
+    int ret = snprintf(sun.sun_path, sizeof(sun.sun_path), "%s/%s", dir, file);
 
-    if (str_cat(sun.sun_path, len, path, COUNT(path)) == len) {
-        if (str_cat(NULL, len + 1, path, COUNT(path)) > len) {
-            errno = EINVAL;
-            return -1;
-        }
+    if (ret <= 0 || (size_t)ret >= sizeof(sun.sun_path)) {
+        errno = EINVAL;
+        return -1;
     }
 
-    *dst = sun;
+    if (dst)
+        *dst = sun;
 
     return 0;
 }
@@ -70,20 +69,14 @@ ctl_bind(int fd, const char *dir, const char *file)
 
         if (ctl_setsun(&sun, dir, name))
             return -1;
-
-        if (!bind(fd, (struct sockaddr *)&sun, sizeof(sun)))
-            return 0;
     } else {
         if (ctl_setsun(&sun, dir, file))
             return -1;
 
         unlink(sun.sun_path);
-
-        if (!bind(fd, (struct sockaddr *)&sun, sizeof(sun)))
-            return 0;
     }
 
-    return -1;
+    return bind(fd, (struct sockaddr *)&sun, sizeof(sun));
 }
 
 void

src/iface.c

@@ -1,7 +1,7 @@
 #include "common.h"
 #include "iface.h"
-#include "str.h"
 
+#include <stdio.h>
 #include <net/if.h>
 #include <sys/ioctl.h>
 
@@ -17,13 +17,11 @@ iface_set_mtu(const char *dev_name, size_t mtu)
         .ifr_mtu = (int)mtu,
     };
 
-    const size_t len = sizeof(ifr.ifr_name) - 1;
+    int ret = snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s", dev_name);
 
-    if (str_cpy(ifr.ifr_name, len, dev_name) == len) {
-        if (str_len(dev_name, len + 1) > len) {
-            errno = EINTR;
-            return -1;
-        }
+    if (ret <= 0 || (size_t)ret >= sizeof(ifr.ifr_name)) {
+        errno = EINVAL;
+        return -1;
     }
 
     int fd = socket(AF_INET, SOCK_DGRAM, 0);
@@ -31,7 +29,7 @@ iface_set_mtu(const char *dev_name, size_t mtu)
     if (fd == -1)
         return -1;
 
-    int ret = ioctl(fd, SIOCSIFMTU, &ifr);
+    ret = ioctl(fd, SIOCSIFMTU, &ifr);
 
     int err = errno;
     close(fd);

src/str.h

@@ -31,32 +31,3 @@ str_len(const char *restrict str, size_t len)
 
     return strnlen(str, len);
 }
-
-static inline size_t
-str_cat(char *dst, size_t dst_len, const char **src, size_t count)
-{
-    if (count && !src)
-        return 0;
-
-    size_t len = 0;
-
-    for (size_t i = 0; i < count && dst_len > len; i++) {
-        size_t n = str_len(src[i], dst_len - len);
-
-        if (dst && n)
-            memmove(&dst[len], src[i], n);
-
-        len += n;
-    }
-
-    if (dst)
-        dst[len] = 0;
-
-    return len;
-}
-
-static inline size_t
-str_cpy(char *dst, size_t dst_len, const char *src)
-{
-    return str_cat(dst, dst_len, &src, 1);
-}

src/tun.c

@@ -32,9 +32,9 @@
 static int
 tun_create_by_id(char *name, size_t len, unsigned id)
 {
-    int ret = snprintf(name, len + 1, "utun%u", id);
+    int ret = snprintf(name, len, "utun%u", id);
 
-    if (ret <= 0 || ret > len) {
+    if (ret <= 0 || (size_t)ret >= len) {
         errno = EINVAL;
         return -1;
     }
@@ -44,8 +44,9 @@ tun_create_by_id(char *name, size_t len, unsigned id)
     if (fd == -1)
         return -1;
 
-    struct ctl_info ci = {0};
-    str_cpy(ci.ctl_name, sizeof(ci.ctl_name) - 1, UTUN_CONTROL_NAME);
+    struct ctl_info ci = {
+        .ctl_name = UTUN_CONTROL_NAME,
+    };
 
     if (ioctl(fd, CTLIOCGINFO, &ci)) {
         int err = errno;
@@ -92,14 +93,20 @@ tun_create_by_name(char *name, size_t len, const char *dev_name)
 static int
 tun_create_by_name(char *name, size_t len, const char *dev_name)
 {
+    int ret = snprintf(name, len, "%s", dev_name);
+
+    if (ret <= 0 || (size_t)ret >= len) {
+        errno = EINVAL;
+        return -1;
+    }
+
     struct ifreq ifr = {
         .ifr_flags = IFF_TUN | IFF_NO_PI,
     };
 
-    const size_t ifr_len = sizeof(ifr.ifr_name) - 1;
+    ret = snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s", dev_name);
 
-    if ((len < ifr_len) ||
-        (str_len(dev_name, ifr_len + 1) > ifr_len)) {
+    if (ret <= 0 || (size_t)ret >= sizeof(ifr.ifr_name)) {
         errno = EINVAL;
         return -1;
     }
@@ -109,8 +116,6 @@ tun_create_by_name(char *name, size_t len, const char *dev_name)
     if (fd == -1)
         return -1;
 
-    str_cpy(ifr.ifr_name, ifr_len, dev_name);
-
     if (ioctl(fd, TUNSETIFF, &ifr)) {
         int err = errno;
         close(fd);
@@ -118,8 +123,6 @@ tun_create_by_name(char *name, size_t len, const char *dev_name)
         return -1;
     }
 
-    str_cpy(name, len, ifr.ifr_name);
-
     return fd;
 }
 
@@ -128,21 +131,13 @@ tun_create_by_name(char *name, size_t len, const char *dev_name)
 static int
 tun_create_by_name(char *name, size_t len, const char *dev_name)
 {
-    char tmp[128];
-    int ret = snprintf(tmp, sizeof(tmp), "/dev/%s", dev_name);
+    int ret = snprintf(name, len, "/dev/%s", dev_name);
 
-    if (ret <= 0 || (size_t)ret >= sizeof(tmp)) {
+    if (ret <= 0 || (size_t)ret >= len) {
         errno = EINVAL;
         return -1;
     }
 
-    if (str_cpy(name, len, dev_name) == len) {
-        if (str_len(dev_name, len + 1) > len) {
-            errno = EINVAL;
-            return -1;
-        }
-    }
-
     return open(tmp, O_RDWR);
 }