wg: support horrible freebsd/osx/unix semantics

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

diff --git a/src/kernel.c b/src/kernel.c
index da80d95813bd23c4a63840852f9fed9c171b1c5d..ad5d1fe618cc14a8970c6ca5aff1bab6fb23214e 100644 (file)
--- a/src/kernel.c
+++ b/src/kernel.c
@@ -80,14 +80,40 @@ static int add_next_to_inflatable_buffer(struct inflatable_buffer *buffer)
        return 0;
 }
 
+#ifndef __linux__
+static void close_and_unlink(int fd)
+{
+       struct sockaddr_un addr;
+       socklen_t len = sizeof(addr);
+
+       if (!getsockname(fd, (struct sockaddr *)&addr, &len))
+               unlink(addr.sun_path);
+       close(fd);
+}
+#endif
+
 static int userspace_interface_fd(const char *interface)
 {
        struct stat sbuf;
        struct sockaddr_un addr = { .sun_family = AF_UNIX };
+#ifndef __linux__
+       struct sockaddr_un bind_addr = { .sun_family = AF_UNIX };
+       mode_t old_umask;
+#endif
        int fd = -1, ret;
+
+       ret = -EINVAL;
+       if (strchr(interface, '/'))
+               goto out;
        ret = snprintf(addr.sun_path, sizeof(addr.sun_path) - 1, SOCK_PATH "%s" SOCK_SUFFIX, interface);
        if (ret < 0)
                goto out;
+#ifndef __linux__
+       ret = snprintf(bind_addr.sun_path, sizeof(bind_addr.sun_path) - 1, SOCK_PATH ".wg-tool-%s-%d.client", interface, getpid());
+       if (ret < 0)
+               goto out;
+       unlink(bind_addr.sun_path);
+#endif
        ret = stat(addr.sun_path, &sbuf);
        if (ret < 0)
                goto out;
@@ -98,9 +124,16 @@ static int userspace_interface_fd(const char *interface)
        ret = fd = socket(AF_UNIX, SOCK_DGRAM, 0);
        if (ret < 0)
                goto out;
+#ifdef __linux__
        ret = bind(fd, (struct sockaddr *)&addr, sizeof(sa_family_t));
+#else
+       old_umask = umask(0077);
+       ret = bind(fd, (struct sockaddr *)&bind_addr, sizeof(bind_addr));
+       umask(old_umask);
+#endif
        if (ret < 0)
                goto out;
+
        ret = connect(fd, (struct sockaddr *)&addr, sizeof(addr));
        if (ret < 0) {
                if (errno == ECONNREFUSED) /* If the process is gone, we try to clean up the socket. */
@@ -109,7 +142,11 @@ static int userspace_interface_fd(const char *interface)
        }
 out:
        if (ret && fd >= 0)
+#ifdef __linux__
                close(fd);
+#else
+               close_and_unlink(fd);
+#endif
        if (!ret)
                ret = fd;
        return ret;
@@ -120,7 +157,11 @@ static bool userspace_has_wireguard_interface(const char *interface)
        int fd = userspace_interface_fd(interface);
        if (fd < 0)
                return false;
+#ifdef __linux__
        close(fd);
+#else
+       close_and_unlink(fd);
+#endif
        return true;
 }
 
@@ -178,14 +219,23 @@ static int userspace_set_device(struct wgdevice *dev)
                goto out;
        ret = ret_code;
 out:
+#ifdef __linux__
        close(fd);
+#else
+       close_and_unlink(fd);
+#endif
        return (int)ret;
 }
 
 static int userspace_get_device(struct wgdevice **dev, const char *interface)
 {
+#ifdef __linux__
        ssize_t len;
-       int ret, fd = userspace_interface_fd(interface);
+#else
+       int len;
+#endif
+       ssize_t ret;
+       int fd = userspace_interface_fd(interface);
        if (fd < 0)
                return fd;
        *dev = NULL;
@@ -193,9 +243,20 @@ static int userspace_get_device(struct wgdevice **dev, const char *interface)
        if (ret < 0)
                goto out;
 
+#ifdef __linux__
        ret = len = recv(fd, NULL, 0, MSG_PEEK | MSG_TRUNC);
        if (len < 0)
                goto out;
+#else
+       ret = recv(fd, &ret, 1, MSG_PEEK);
+       if (ret < 0)
+               goto out;
+       ret = ioctl(fd, FIONREAD, &len);
+       if (ret < 0) {
+               ret = -errno;
+               goto out;
+       }
+#endif
        ret = -EBADMSG;
        if ((size_t)len < sizeof(struct wgdevice))
                goto out;
@@ -212,7 +273,11 @@ static int userspace_get_device(struct wgdevice **dev, const char *interface)
 out:
        if (*dev && ret)
                free(*dev);
+#ifdef __linux__
        close(fd);
+#else
+       close_and_unlink(fd);
+#endif
        errno = -ret;
        return ret;
 }