contrib/hostapd-0.4.9/wpa_ctrl.c

   1 /*
   2  * wpa_supplicant/hostapd control interface library
   3  * Copyright (c) 2004-2005, Jouni Malinen <jkmaline@cc.hut.fi>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * Alternatively, this software may be distributed under the terms of BSD
  10  * license.
  11  *
  12  * See README and COPYING for more details.
  13  */
  14
  15 #include <stdlib.h>
  16 #include <stdio.h>
  17 #include <string.h>
  18 #include <unistd.h>
  19 #include <sys/types.h>
  20 #include <sys/time.h>
  21 #ifndef CONFIG_NATIVE_WINDOWS
  22 #include <sys/socket.h>
  23 #include <netinet/in.h>
  24 #include <sys/un.h>
  25 #endif /* CONFIG_NATIVE_WINDOWS */
  26
  27 #include "wpa_ctrl.h"
  28 #ifdef CONFIG_NATIVE_WINDOWS
  29 #include "common.h"
  30 #endif /* CONFIG_NATIVE_WINDOWS */
  31
  32
  33 /**
  34  * struct wpa_ctrl - Internal structure for control interface library
  35  *
  36  * This structure is used by the wpa_supplicant/hostapd control interface
  37  * library to store internal data. Programs using the library should not touch
  38  * this data directly. They can only use the pointer to the data structure as
  39  * an identifier for the control interface connection and use this as one of
  40  * the arguments for most of the control interface library functions.
  41  */
  42 struct wpa_ctrl {
  43         int s;
  44 #ifdef CONFIG_CTRL_IFACE_UDP
  45         struct sockaddr_in local;
  46         struct sockaddr_in dest;
  47 #else /* CONFIG_CTRL_IFACE_UDP */
  48         struct sockaddr_un local;
  49         struct sockaddr_un dest;
  50 #endif /* CONFIG_CTRL_IFACE_UDP */
  51 };
  52
  53
  54 struct wpa_ctrl * wpa_ctrl_open(const char *ctrl_path)
  55 {
  56         struct wpa_ctrl *ctrl;
  57 #ifndef CONFIG_CTRL_IFACE_UDP
  58         static int counter = 0;
  59 #endif /* CONFIG_CTRL_IFACE_UDP */
  60
  61         ctrl = malloc(sizeof(*ctrl));
  62         if (ctrl == NULL)
  63                 return NULL;
  64         memset(ctrl, 0, sizeof(*ctrl));
  65
  66 #ifdef CONFIG_CTRL_IFACE_UDP
  67         ctrl->s = socket(PF_INET, SOCK_DGRAM, 0);
  68         if (ctrl->s < 0) {
  69                 perror("socket");
  70                 free(ctrl);
  71                 return NULL;
  72         }
  73
  74         ctrl->local.sin_family = AF_INET;
  75         ctrl->local.sin_addr.s_addr = htonl((127 << 24) | 1);
  76         if (bind(ctrl->s, (struct sockaddr *) &ctrl->local,
  77                  sizeof(ctrl->local)) < 0) {
  78                 close(ctrl->s);
  79                 free(ctrl);
  80                 return NULL;
  81         }
  82
  83         ctrl->dest.sin_family = AF_INET;
  84         ctrl->dest.sin_addr.s_addr = htonl((127 << 24) | 1);
  85         ctrl->dest.sin_port = htons(WPA_CTRL_IFACE_PORT);
  86         if (connect(ctrl->s, (struct sockaddr *) &ctrl->dest,
  87                     sizeof(ctrl->dest)) < 0) {
  88                 perror("connect");
  89                 close(ctrl->s);
  90                 free(ctrl);
  91                 return NULL;
  92         }
  93 #else /* CONFIG_CTRL_IFACE_UDP */
  94         ctrl->s = socket(PF_UNIX, SOCK_DGRAM, 0);
  95         if (ctrl->s < 0) {
  96                 free(ctrl);
  97                 return NULL;
  98         }
  99
 100         ctrl->local.sun_family = AF_UNIX;
 101         snprintf(ctrl->local.sun_path, sizeof(ctrl->local.sun_path),
 102                  "/tmp/wpa_ctrl_%d-%d", getpid(), counter++);
 103         if (bind(ctrl->s, (struct sockaddr *) &ctrl->local,
 104                     sizeof(ctrl->local)) < 0) {
 105                 close(ctrl->s);
 106                 free(ctrl);
 107                 return NULL;
 108         }
 109
 110         ctrl->dest.sun_family = AF_UNIX;
 111         snprintf(ctrl->dest.sun_path, sizeof(ctrl->dest.sun_path), "%s",
 112                  ctrl_path);
 113         if (connect(ctrl->s, (struct sockaddr *) &ctrl->dest,
 114                     sizeof(ctrl->dest)) < 0) {
 115                 close(ctrl->s);
 116                 unlink(ctrl->local.sun_path);
 117                 free(ctrl);
 118                 return NULL;
 119         }
 120 #endif /* CONFIG_CTRL_IFACE_UDP */
 121
 122         return ctrl;
 123 }
 124
 125
 126 void wpa_ctrl_close(struct wpa_ctrl *ctrl)
 127 {
 128 #ifndef CONFIG_CTRL_IFACE_UDP
 129         unlink(ctrl->local.sun_path);
 130 #endif /* CONFIG_CTRL_IFACE_UDP */
 131         close(ctrl->s);
 132         free(ctrl);
 133 }
 134
 135
 136 int wpa_ctrl_request(struct wpa_ctrl *ctrl, const char *cmd, size_t cmd_len,
 137                      char *reply, size_t *reply_len,
 138                      void (*msg_cb)(char *msg, size_t len))
 139 {
 140         struct timeval tv;
 141         int res;
 142         fd_set rfds;
 143
 144         if (send(ctrl->s, cmd, cmd_len, 0) < 0)
 145                 return -1;
 146
 147         for (;;) {
 148                 tv.tv_sec = 2;
 149                 tv.tv_usec = 0;
 150                 FD_ZERO(&rfds);
 151                 FD_SET(ctrl->s, &rfds);
 152                 res = select(ctrl->s + 1, &rfds, NULL, NULL, &tv);
 153                 if (FD_ISSET(ctrl->s, &rfds)) {
 154                         res = recv(ctrl->s, reply, *reply_len, 0);
 155                         if (res < 0)
 156                                 return res;
 157                         if (res > 0 && reply[0] == '<') {
 158                                 /* This is an unsolicited message from
 159                                  * wpa_supplicant, not the reply to the
 160                                  * request. Use msg_cb to report this to the
 161                                  * caller. */
 162                                 if (msg_cb) {
 163                                         /* Make sure the message is nul
 164                                          * terminated. */
 165                                         if ((size_t) res == *reply_len)
 166                                                 res = (*reply_len) - 1;
 167                                         reply[res] = '\0';
 168                                         msg_cb(reply, res);
 169                                 }
 170                                 continue;
 171                         }
 172                         *reply_len = res;
 173                         break;
 174                 } else {
 175                         return -2;
 176                 }
 177         }
 178         return 0;
 179 }
 180
 181
 182 static int wpa_ctrl_attach_helper(struct wpa_ctrl *ctrl, int attach)
 183 {
 184         char buf[10];
 185         int ret;
 186         size_t len = 10;
 187
 188         ret = wpa_ctrl_request(ctrl, attach ? "ATTACH" : "DETACH", 6,
 189                                buf, &len, NULL);
 190         if (ret < 0)
 191                 return ret;
 192         if (len == 3 && memcmp(buf, "OK\n", 3) == 0)
 193                 return 0;
 194         return -1;
 195 }
 196
 197
 198 int wpa_ctrl_attach(struct wpa_ctrl *ctrl)
 199 {
 200         return wpa_ctrl_attach_helper(ctrl, 1);
 201 }
 202
 203
 204 int wpa_ctrl_detach(struct wpa_ctrl *ctrl)
 205 {
 206         return wpa_ctrl_attach_helper(ctrl, 0);
 207 }
 208
 209
 210 int wpa_ctrl_recv(struct wpa_ctrl *ctrl, char *reply, size_t *reply_len)
 211 {
 212         int res;
 213
 214         res = recv(ctrl->s, reply, *reply_len, 0);
 215         if (res < 0)
 216                 return res;
 217         *reply_len = res;
 218         return 0;
 219 }
 220
 221
 222 int wpa_ctrl_pending(struct wpa_ctrl *ctrl)
 223 {
 224         struct timeval tv;
 225         int res;
 226         fd_set rfds;
 227         tv.tv_sec = 0;
 228         tv.tv_usec = 0;
 229         FD_ZERO(&rfds);
 230         FD_SET(ctrl->s, &rfds);
 231         res = select(ctrl->s + 1, &rfds, NULL, NULL, &tv);
 232         return FD_ISSET(ctrl->s, &rfds);
 233 }
 234
 235
 236 int wpa_ctrl_get_fd(struct wpa_ctrl *ctrl)
 237 {
 238         return ctrl->s;
 239 }