lib/stream-unix.c

   1 /*
   2  * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015 Nicira, Inc.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #include <config.h>
  18 #include "stream.h"
  19 #include <errno.h>
  20 #include <inttypes.h>
  21 #include <netdb.h>
  22 #include <poll.h>
  23 #include <sys/socket.h>
  24 #include <sys/types.h>
  25 #include <sys/un.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <unistd.h>
  29 #include "ovs-atomic.h"
  30 #include "packets.h"
  31 #include "openvswitch/poll-loop.h"
  32 #include "socket-util.h"
  33 #include "dirs.h"
  34 #include "util.h"
  35 #include "stream-provider.h"
  36 #include "stream-fd.h"
  37 #include "openvswitch/vlog.h"
  38
  39 VLOG_DEFINE_THIS_MODULE(stream_unix);
  40
  41 /* Active UNIX socket. */
  42
  43 static int
  44 unix_open(const char *name, char *suffix, struct stream **streamp,
  45           uint8_t dscp OVS_UNUSED)
  46 {
  47     char *connect_path;
  48     int fd;
  49
  50     connect_path = abs_file_name(ovs_rundir(), suffix);
  51     fd = make_unix_socket(SOCK_STREAM, true, NULL, connect_path);
  52
  53     if (fd < 0) {
  54         VLOG_DBG("%s: connection failed (%s)",
  55                  connect_path, ovs_strerror(-fd));
  56         free(connect_path);
  57         return -fd;
  58     }
  59
  60     free(connect_path);
  61     return new_fd_stream(xstrdup(name), fd, check_connection_completion(fd),
  62                          AF_UNIX, streamp);
  63 }
  64
  65 const struct stream_class unix_stream_class = {
  66     "unix",                     /* name */
  67     false,                      /* needs_probes */
  68     unix_open,                  /* open */
  69     NULL,                       /* close */
  70     NULL,                       /* connect */
  71     NULL,                       /* recv */
  72     NULL,                       /* send */
  73     NULL,                       /* run */
  74     NULL,                       /* run_wait */
  75     NULL,                       /* wait */
  76 };
  77 \f
  78 /* Passive UNIX socket. */
  79
  80 static int punix_accept(int fd, const struct sockaddr_storage *ss,
  81                         size_t ss_len, struct stream **streamp);
  82
  83 static int
  84 punix_open(const char *name OVS_UNUSED, char *suffix,
  85            struct pstream **pstreamp, uint8_t dscp OVS_UNUSED)
  86 {
  87     char *bind_path;
  88     int fd, error;
  89
  90     bind_path = abs_file_name(ovs_rundir(), suffix);
  91     fd = make_unix_socket(SOCK_STREAM, true, bind_path, NULL);
  92     if (fd < 0) {
  93         VLOG_ERR("%s: binding failed: %s", bind_path, ovs_strerror(errno));
  94         free(bind_path);
  95         return errno;
  96     }
  97
  98     if (listen(fd, 64) < 0) {
  99         error = errno;
 100         VLOG_ERR("%s: listen: %s", name, ovs_strerror(error));
 101         close(fd);
 102         free(bind_path);
 103         return error;
 104     }
 105
 106     return new_fd_pstream(xstrdup(name), fd,
 107                           punix_accept, bind_path, pstreamp);
 108 }
 109
 110 static int
 111 punix_accept(int fd, const struct sockaddr_storage *ss, size_t ss_len,
 112              struct stream **streamp)
 113 {
 114     const struct sockaddr_un *sun = (const struct sockaddr_un *) ss;
 115     int name_len = get_unix_name_len(sun, ss_len);
 116     char *bound_name;
 117
 118     if (name_len > 0) {
 119         bound_name = xasprintf("unix:%.*s", name_len, sun->sun_path);
 120     } else {
 121         /* When a Unix socket connects to us without first binding a name, we
 122          * don't get any name for it.  It's useful nevertheless to be able to
 123          * distinguish separate sockets in log messages, so use a counter. */
 124         static atomic_count next_idx = ATOMIC_COUNT_INIT(0);
 125         bound_name = xasprintf("unix#%u", atomic_count_inc(&next_idx));
 126     }
 127     return new_fd_stream(bound_name, fd, 0, AF_UNIX, streamp);
 128 }
 129
 130 const struct pstream_class punix_pstream_class = {
 131     "punix",
 132     false,
 133     punix_open,
 134     NULL,
 135     NULL,
 136     NULL,
 137 };
 138