af_unix: backport helper functions

This backports various helpers associated with seccomp notify to make
maintenance easier.

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

diff --git a/src/lxc/af_unix.c b/src/lxc/af_unix.c
index 06700fac1ead675980f66c19facd61e8930d1fcc..328f891f0b7a3d7384acc044ab75961370e03b0b 100644 (file)
--- a/src/lxc/af_unix.c
+++ b/src/lxc/af_unix.c
@@ -316,3 +316,73 @@ int lxc_abstract_unix_rcv_credential(int fd, void *data, size_t size)
 out:
        return ret;
 }
+
+int lxc_unix_sockaddr(struct sockaddr_un *ret, const char *path)
+{
+       size_t len;
+
+       len = strlen(path);
+       if (len == 0)
+               return minus_one_set_errno(EINVAL);
+       if (path[0] != '/' && path[0] != '@')
+               return minus_one_set_errno(EINVAL);
+       if (path[1] == '\0')
+               return minus_one_set_errno(EINVAL);
+
+       if (len + 1 > sizeof(ret->sun_path))
+               return minus_one_set_errno(EINVAL);
+
+       *ret = (struct sockaddr_un){
+           .sun_family = AF_UNIX,
+       };
+
+       if (path[0] == '@') {
+               memcpy(ret->sun_path + 1, path + 1, len);
+               return (int)(offsetof(struct sockaddr_un, sun_path) + len);
+       }
+
+       memcpy(ret->sun_path, path, len + 1);
+       return (int)(offsetof(struct sockaddr_un, sun_path) + len + 1);
+}
+
+int lxc_unix_connect(struct sockaddr_un *addr)
+{
+       __do_close_prot_errno int fd = -EBADF;
+       int ret;
+       ssize_t len;
+
+       fd = socket(PF_UNIX, SOCK_STREAM, SOCK_CLOEXEC);
+       if (fd < 0)
+               return -1;
+
+       if (addr->sun_path[0] == '\0')
+               len = strlen(&addr->sun_path[1]);
+       else
+               len = strlen(&addr->sun_path[0]);
+       ret = connect(fd, (struct sockaddr *)&addr,
+                     offsetof(struct sockaddr_un, sun_path) + len + 1);
+       if (ret < 0)
+               return -1;
+
+       return move_fd(fd);
+}
+
+int lxc_socket_set_timeout(int fd, int rcv_timeout, int snd_timeout)
+{
+       struct timeval out = {0};
+       int ret;
+
+       out.tv_sec = snd_timeout;
+       ret = setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, (const void *)&out,
+                        sizeof(out));
+       if (ret < 0)
+               return -1;
+
+       out.tv_sec = rcv_timeout;
+       ret = setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, (const void *)&out,
+                        sizeof(out));
+       if (ret < 0)
+               return -1;
+
+       return 0;
+}

diff --git a/src/lxc/af_unix.h b/src/lxc/af_unix.h
index f2c2fdcc6eeae2d8f1b77aaeae7b66e60e2a9252..3ae5954983d811ec28aea5ef019a2c5dcfebcbd9 100644 (file)
--- a/src/lxc/af_unix.h
+++ b/src/lxc/af_unix.h
@@ -25,6 +25,8 @@
 #define __LXC_AF_UNIX_H
 
 #include <stdio.h>
+#include <sys/socket.h>
+#include <sys/un.h>
 
 /* does not enforce \0-termination */
 extern int lxc_abstract_unix_open(const char *path, int type, int flags);
@@ -37,5 +39,8 @@ extern int lxc_abstract_unix_recv_fds(int fd, int *recvfds, int num_recvfds,
                                      void *data, size_t size);
 extern int lxc_abstract_unix_send_credential(int fd, void *data, size_t size);
 extern int lxc_abstract_unix_rcv_credential(int fd, void *data, size_t size);
+extern int lxc_unix_sockaddr(struct sockaddr_un *ret, const char *path);
+extern int lxc_unix_connect(struct sockaddr_un *addr);
+extern int lxc_socket_set_timeout(int fd, int rcv_timeout, int snd_timeout);
 
 #endif /* __LXC_AF_UNIX_H */