/* * wpa_supplicant/hostapd control interface library * Copyright (c) 2004-2007, Jouni Malinen * * This software may be distributed under the terms of the BSD license. * See README for more details. */ #include "includes.h" #ifdef CONFIG_CTRL_IFACE #ifdef CONFIG_CTRL_IFACE_UNIX #include #include #include #include #include #endif /* CONFIG_CTRL_IFACE_UNIX */ #ifdef CONFIG_CTRL_IFACE_UDP_REMOTE #include #endif /* CONFIG_CTRL_IFACE_UDP_REMOTE */ #ifdef ANDROID #include #include #include #include "private/android_filesystem_config.h" #endif /* ANDROID */ #ifdef CONFIG_CTRL_IFACE_UDP_IPV6 #include #endif /* CONFIG_CTRL_IFACE_UDP_IPV6 */ #include "wpa_ctrl.h" #include "common.h" #if defined(CONFIG_CTRL_IFACE_UNIX) || defined(CONFIG_CTRL_IFACE_UDP) #define CTRL_IFACE_SOCKET #endif /* CONFIG_CTRL_IFACE_UNIX || CONFIG_CTRL_IFACE_UDP */ /** * struct wpa_ctrl - Internal structure for control interface library * * This structure is used by the wpa_supplicant/hostapd control interface * library to store internal data. Programs using the library should not touch * this data directly. They can only use the pointer to the data structure as * an identifier for the control interface connection and use this as one of * the arguments for most of the control interface library functions. */ struct wpa_ctrl { #ifdef CONFIG_CTRL_IFACE_UDP int s; #ifdef CONFIG_CTRL_IFACE_UDP_IPV6 struct sockaddr_in6 local; struct sockaddr_in6 dest; #else /* CONFIG_CTRL_IFACE_UDP_IPV6 */ struct sockaddr_in local; struct sockaddr_in dest; #endif /* CONFIG_CTRL_IFACE_UDP_IPV6 */ char *cookie; char *remote_ifname; char *remote_ip; #endif /* CONFIG_CTRL_IFACE_UDP */ #ifdef CONFIG_CTRL_IFACE_UNIX int s; struct sockaddr_un local; struct sockaddr_un dest; #endif /* CONFIG_CTRL_IFACE_UNIX */ #ifdef CONFIG_CTRL_IFACE_NAMED_PIPE HANDLE pipe; #endif /* CONFIG_CTRL_IFACE_NAMED_PIPE */ }; #ifdef CONFIG_CTRL_IFACE_UNIX #ifndef CONFIG_CTRL_IFACE_CLIENT_DIR #define CONFIG_CTRL_IFACE_CLIENT_DIR "/tmp" #endif /* CONFIG_CTRL_IFACE_CLIENT_DIR */ #ifndef CONFIG_CTRL_IFACE_CLIENT_PREFIX #define CONFIG_CTRL_IFACE_CLIENT_PREFIX "wpa_ctrl_" #endif /* CONFIG_CTRL_IFACE_CLIENT_PREFIX */ struct wpa_ctrl * wpa_ctrl_open(const char *ctrl_path) { return wpa_ctrl_open2(ctrl_path, NULL); } struct wpa_ctrl * wpa_ctrl_open2(const char *ctrl_path, const char *cli_path) { struct wpa_ctrl *ctrl; static int counter = 0; int ret; size_t res; int tries = 0; int flags; if (ctrl_path == NULL) return NULL; ctrl = os_zalloc(sizeof(*ctrl)); if (ctrl == NULL) return NULL; ctrl->s = socket(PF_UNIX, SOCK_DGRAM, 0); if (ctrl->s < 0) { os_free(ctrl); return NULL; } ctrl->local.sun_family = AF_UNIX; counter++; try_again: if (cli_path && cli_path[0] == '/') { ret = os_snprintf(ctrl->local.sun_path, sizeof(ctrl->local.sun_path), "%s/" CONFIG_CTRL_IFACE_CLIENT_PREFIX "%d-%d", cli_path, (int) getpid(), counter); } else { ret = os_snprintf(ctrl->local.sun_path, sizeof(ctrl->local.sun_path), CONFIG_CTRL_IFACE_CLIENT_DIR "/" CONFIG_CTRL_IFACE_CLIENT_PREFIX "%d-%d", (int) getpid(), counter); } if (os_snprintf_error(sizeof(ctrl->local.sun_path), ret)) { close(ctrl->s); os_free(ctrl); return NULL; } tries++; #ifdef ANDROID /* Set client socket file permissions so that bind() creates the client * socket with these permissions and there is no need to try to change * them with chmod() after bind() which would have potential issues with * race conditions. These permissions are needed to make sure the server * side (wpa_supplicant or hostapd) can reply to the control interface * messages. * * The lchown() calls below after bind() are also part of the needed * operations to allow the response to go through. Those are using the * no-deference-symlinks version to avoid races. */ fchmod(ctrl->s, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP); #endif /* ANDROID */ if (bind(ctrl->s, (struct sockaddr *) &ctrl->local, sizeof(ctrl->local)) < 0) { if (errno == EADDRINUSE && tries < 2) { /* * getpid() returns unique identifier for this instance * of wpa_ctrl, so the existing socket file must have * been left by unclean termination of an earlier run. * Remove the file and try again. */ unlink(ctrl->local.sun_path); goto try_again; } close(ctrl->s); os_free(ctrl); return NULL; } #ifdef ANDROID /* Set group even if we do not have privileges to change owner */ lchown(ctrl->local.sun_path, -1, AID_WIFI); lchown(ctrl->local.sun_path, AID_SYSTEM, AID_WIFI); if (os_strncmp(ctrl_path, "@android:", 9) == 0) { if (socket_local_client_connect( ctrl->s, ctrl_path + 9, ANDROID_SOCKET_NAMESPACE_RESERVED, SOCK_DGRAM) < 0) { close(ctrl->s); unlink(ctrl->local.sun_path); os_free(ctrl); return NULL; } return ctrl; } /* * If the ctrl_path isn't an absolute pathname, assume that * it's the name of a socket in the Android reserved namespace. * Otherwise, it's a normal UNIX domain socket appearing in the * filesystem. */ if (*ctrl_path != '/') { char buf[21]; os_snprintf(buf, sizeof(buf), "wpa_%s", ctrl_path); if (socket_local_client_connect( ctrl->s, buf, ANDROID_SOCKET_NAMESPACE_RESERVED, SOCK_DGRAM) < 0) { close(ctrl->s); unlink(ctrl->local.sun_path); os_free(ctrl); return NULL; } return ctrl; } #endif /* ANDROID */ ctrl->dest.sun_family = AF_UNIX; if (os_strncmp(ctrl_path, "@abstract:", 10) == 0) { ctrl->dest.sun_path[0] = '\0'; os_strlcpy(ctrl->dest.sun_path + 1, ctrl_path + 10, sizeof(ctrl->dest.sun_path) - 1); } else { res = os_strlcpy(ctrl->dest.sun_path, ctrl_path, sizeof(ctrl->dest.sun_path)); if (res >= sizeof(ctrl->dest.sun_path)) { close(ctrl->s); os_free(ctrl); return NULL; } } if (connect(ctrl->s, (struct sockaddr *) &ctrl->dest, sizeof(ctrl->dest)) < 0) { close(ctrl->s); unlink(ctrl->local.sun_path); os_free(ctrl); return NULL; } /* * Make socket non-blocking so that we don't hang forever if * target dies unexpectedly. */ flags = fcntl(ctrl->s, F_GETFL); if (flags >= 0) { flags |= O_NONBLOCK; if (fcntl(ctrl->s, F_SETFL, flags) < 0) { perror("fcntl(ctrl->s, O_NONBLOCK)"); /* Not fatal, continue on.*/ } } return ctrl; } void wpa_ctrl_close(struct wpa_ctrl *ctrl) { if (ctrl == NULL) return; unlink(ctrl->local.sun_path); if (ctrl->s >= 0) close(ctrl->s); os_free(ctrl); } #ifdef ANDROID /** * wpa_ctrl_cleanup() - Delete any local UNIX domain socket files that * may be left over from clients that were previously connected to * wpa_supplicant. This keeps these files from being orphaned in the * event of crashes that prevented them from being removed as part * of the normal orderly shutdown. */ void wpa_ctrl_cleanup(void) { DIR *dir; struct dirent *result; size_t dirnamelen; size_t maxcopy; char pathname[PATH_MAX]; char *namep; if ((dir = opendir(CONFIG_CTRL_IFACE_CLIENT_DIR)) == NULL) return; dirnamelen = (size_t) os_snprintf(pathname, sizeof(pathname), "%s/", CONFIG_CTRL_IFACE_CLIENT_DIR); if (dirnamelen >= sizeof(pathname)) { closedir(dir); return; } namep = pathname + dirnamelen; maxcopy = PATH_MAX - dirnamelen; while ((result = readdir(dir)) != NULL) { if (os_strlcpy(namep, result->d_name, maxcopy) < maxcopy) unlink(pathname); } closedir(dir); } #endif /* ANDROID */ #else /* CONFIG_CTRL_IFACE_UNIX */ #ifdef ANDROID void wpa_ctrl_cleanup(void) { } #endif /* ANDROID */ #endif /* CONFIG_CTRL_IFACE_UNIX */ #ifdef CONFIG_CTRL_IFACE_UDP struct wpa_ctrl * wpa_ctrl_open(const char *ctrl_path) { struct wpa_ctrl *ctrl; char buf[128]; size_t len; #ifdef CONFIG_CTRL_IFACE_UDP_REMOTE struct hostent *h; #endif /* CONFIG_CTRL_IFACE_UDP_REMOTE */ ctrl = os_zalloc(sizeof(*ctrl)); if (ctrl == NULL) return NULL; #ifdef CONFIG_CTRL_IFACE_UDP_IPV6 ctrl->s = socket(PF_INET6, SOCK_DGRAM, 0); #else /* CONFIG_CTRL_IFACE_UDP_IPV6 */ ctrl->s = socket(PF_INET, SOCK_DGRAM, 0); #endif /* CONFIG_CTRL_IFACE_UDP_IPV6 */ if (ctrl->s < 0) { perror("socket"); os_free(ctrl); return NULL; } #ifdef CONFIG_CTRL_IFACE_UDP_IPV6 ctrl->local.sin6_family = AF_INET6; #ifdef CONFIG_CTRL_IFACE_UDP_REMOTE ctrl->local.sin6_addr = in6addr_any; #else /* CONFIG_CTRL_IFACE_UDP_REMOTE */ inet_pton(AF_INET6, "::1", &ctrl->local.sin6_addr); #endif /* CONFIG_CTRL_IFACE_UDP_REMOTE */ #else /* CONFIG_CTRL_IFACE_UDP_IPV6 */ ctrl->local.sin_family = AF_INET; #ifdef CONFIG_CTRL_IFACE_UDP_REMOTE ctrl->local.sin_addr.s_addr = INADDR_ANY; #else /* CONFIG_CTRL_IFACE_UDP_REMOTE */ ctrl->local.sin_addr.s_addr = htonl((127 << 24) | 1); #endif /* CONFIG_CTRL_IFACE_UDP_REMOTE */ #endif /* CONFIG_CTRL_IFACE_UDP_IPV6 */ if (bind(ctrl->s, (struct sockaddr *) &ctrl->local, sizeof(ctrl->local)) < 0) { close(ctrl->s); os_free(ctrl); return NULL; } #ifdef CONFIG_CTRL_IFACE_UDP_IPV6 ctrl->dest.sin6_family = AF_INET6; inet_pton(AF_INET6, "::1", &ctrl->dest.sin6_addr); ctrl->dest.sin6_port = htons(WPA_CTRL_IFACE_PORT); #else /* CONFIG_CTRL_IFACE_UDP_IPV6 */ ctrl->dest.sin_family = AF_INET; ctrl->dest.sin_addr.s_addr = htonl((127 << 24) | 1); ctrl->dest.sin_port = htons(WPA_CTRL_IFACE_PORT); #endif /* CONFIG_CTRL_IFACE_UDP_IPV6 */ #ifdef CONFIG_CTRL_IFACE_UDP_REMOTE if (ctrl_path) { char *port, *name; int port_id; #ifdef CONFIG_CTRL_IFACE_UDP_IPV6 char *scope; int scope_id = 0; #endif /* CONFIG_CTRL_IFACE_UDP_IPV6 */ name = os_strdup(ctrl_path); if (name == NULL) { close(ctrl->s); os_free(ctrl); return NULL; } #ifdef CONFIG_CTRL_IFACE_UDP_IPV6 port = os_strchr(name, ','); #else /* CONFIG_CTRL_IFACE_UDP_IPV6 */ port = os_strchr(name, ':'); #endif /* CONFIG_CTRL_IFACE_UDP_IPV6 */ if (port) { port_id = atoi(&port[1]); port[0] = '\0'; } else port_id = WPA_CTRL_IFACE_PORT; #ifdef CONFIG_CTRL_IFACE_UDP_IPV6 scope = os_strchr(name, '%'); if (scope) { scope_id = if_nametoindex(&scope[1]); scope[0] = '\0'; } h = gethostbyname2(name, AF_INET6); #else /* CONFIG_CTRL_IFACE_UDP_IPV6 */ h = gethostbyname(name); #endif /* CONFIG_CTRL_IFACE_UDP_IPV6 */ ctrl->remote_ip = os_strdup(name); os_free(name); if (h == NULL) { perror("gethostbyname"); close(ctrl->s); os_free(ctrl->remote_ip); os_free(ctrl); return NULL; } #ifdef CONFIG_CTRL_IFACE_UDP_IPV6 ctrl->dest.sin6_scope_id = scope_id; ctrl->dest.sin6_port = htons(port_id); os_memcpy(&ctrl->dest.sin6_addr, h->h_addr, h->h_length); #else /* CONFIG_CTRL_IFACE_UDP_IPV6 */ ctrl->dest.sin_port = htons(port_id); os_memcpy(&ctrl->dest.sin_addr.s_addr, h->h_addr, h->h_length); #endif /* CONFIG_CTRL_IFACE_UDP_IPV6 */ } else ctrl->remote_ip = os_strdup("localhost"); #endif /* CONFIG_CTRL_IFACE_UDP_REMOTE */ if (connect(ctrl->s, (struct sockaddr *) &ctrl->dest, sizeof(ctrl->dest)) < 0) { #ifdef CONFIG_CTRL_IFACE_UDP_IPV6 char addr[INET6_ADDRSTRLEN]; wpa_printf(MSG_ERROR, "connect(%s:%d) failed: %s", inet_ntop(AF_INET6, &ctrl->dest.sin6_addr, addr, sizeof(ctrl->dest)), ntohs(ctrl->dest.sin6_port), strerror(errno)); #else /* CONFIG_CTRL_IFACE_UDP_IPV6 */ wpa_printf(MSG_ERROR, "connect(%s:%d) failed: %s", inet_ntoa(ctrl->dest.sin_addr), ntohs(ctrl->dest.sin_port), strerror(errno)); #endif /* CONFIG_CTRL_IFACE_UDP_IPV6 */ close(ctrl->s); os_free(ctrl->remote_ip); os_free(ctrl); return NULL; } len = sizeof(buf) - 1; if (wpa_ctrl_request(ctrl, "GET_COOKIE", 10, buf, &len, NULL) == 0) { buf[len] = '\0'; ctrl->cookie = os_strdup(buf); } if (wpa_ctrl_request(ctrl, "IFNAME", 6, buf, &len, NULL) == 0) { buf[len] = '\0'; ctrl->remote_ifname = os_strdup(buf); } return ctrl; } char * wpa_ctrl_get_remote_ifname(struct wpa_ctrl *ctrl) { #define WPA_CTRL_MAX_PS_NAME 100 static char ps[WPA_CTRL_MAX_PS_NAME] = {}; os_snprintf(ps, WPA_CTRL_MAX_PS_NAME, "%s/%s", ctrl->remote_ip, ctrl->remote_ifname); return ps; } void wpa_ctrl_close(struct wpa_ctrl *ctrl) { close(ctrl->s); os_free(ctrl->cookie); os_free(ctrl->remote_ifname); os_free(ctrl->remote_ip); os_free(ctrl); } #endif /* CONFIG_CTRL_IFACE_UDP */ #ifdef CTRL_IFACE_SOCKET int wpa_ctrl_request(struct wpa_ctrl *ctrl, const char *cmd, size_t cmd_len, char *reply, size_t *reply_len, void (*msg_cb)(char *msg, size_t len)) { struct timeval tv; struct os_reltime started_at, ending_at; int res; fd_set rfds; const char *_cmd; char *cmd_buf = NULL; size_t _cmd_len; #ifdef CONFIG_CTRL_IFACE_UDP if (ctrl->cookie) { char *pos; _cmd_len = os_strlen(ctrl->cookie) + 1 + cmd_len; cmd_buf = os_malloc(_cmd_len); if (cmd_buf == NULL) return -1; _cmd = cmd_buf; pos = cmd_buf; os_strlcpy(pos, ctrl->cookie, _cmd_len); pos += os_strlen(ctrl->cookie); *pos++ = ' '; os_memcpy(pos, cmd, cmd_len); } else #endif /* CONFIG_CTRL_IFACE_UDP */ { _cmd = cmd; _cmd_len = cmd_len; } errno = 0; started_at.sec = 0; started_at.usec = 0; retry_send: if (send(ctrl->s, _cmd, _cmd_len, 0) < 0) { if (errno == EAGAIN || errno == EBUSY || errno == EWOULDBLOCK) { /* * Must be a non-blocking socket... Try for a bit * longer before giving up. */ if (started_at.sec == 0) os_get_reltime(&started_at); else { struct os_reltime n; os_get_reltime(&n); /* Try for a few seconds. */ if (os_reltime_expired(&n, &started_at, 5)) goto send_err; } os_sleep(1, 0); goto retry_send; } send_err: os_free(cmd_buf); return -1; } os_free(cmd_buf); os_get_reltime(&ending_at); ending_at.sec += 10; for (;;) { struct os_reltime diff; os_get_reltime(&started_at); if (os_reltime_before(&ending_at, &started_at)) return -2; os_reltime_sub(&ending_at, &started_at, &diff); tv.tv_sec = diff.sec; tv.tv_usec = diff.usec; FD_ZERO(&rfds); FD_SET(ctrl->s, &rfds); res = select(ctrl->s + 1, &rfds, NULL, NULL, &tv); if (res < 0 && errno == EINTR) continue; if (res < 0) return res; if (FD_ISSET(ctrl->s, &rfds)) { res = recv(ctrl->s, reply, *reply_len, 0); if (res < 0) return res; if ((res > 0 && reply[0] == '<') || (res > 6 && strncmp(reply, "IFNAME=", 7) == 0)) { /* This is an unsolicited message from * wpa_supplicant, not the reply to the * request. Use msg_cb to report this to the * caller. */ if (msg_cb) { /* Make sure the message is nul * terminated. */ if ((size_t) res == *reply_len) res = (*reply_len) - 1; reply[res] = '\0'; msg_cb(reply, res); } continue; } *reply_len = res; break; } else { return -2; } } return 0; } #endif /* CTRL_IFACE_SOCKET */ static int wpa_ctrl_attach_helper(struct wpa_ctrl *ctrl, int attach) { char buf[10]; int ret; size_t len = 10; ret = wpa_ctrl_request(ctrl, attach ? "ATTACH" : "DETACH", 6, buf, &len, NULL); if (ret < 0) return ret; if (len == 3 && os_memcmp(buf, "OK\n", 3) == 0) return 0; return -1; } int wpa_ctrl_attach(struct wpa_ctrl *ctrl) { return wpa_ctrl_attach_helper(ctrl, 1); } int wpa_ctrl_detach(struct wpa_ctrl *ctrl) { return wpa_ctrl_attach_helper(ctrl, 0); } #ifdef CTRL_IFACE_SOCKET int wpa_ctrl_recv(struct wpa_ctrl *ctrl, char *reply, size_t *reply_len) { int res; res = recv(ctrl->s, reply, *reply_len, 0); if (res < 0) return res; *reply_len = res; return 0; } int wpa_ctrl_pending(struct wpa_ctrl *ctrl) { struct timeval tv; fd_set rfds; tv.tv_sec = 0; tv.tv_usec = 0; FD_ZERO(&rfds); FD_SET(ctrl->s, &rfds); select(ctrl->s + 1, &rfds, NULL, NULL, &tv); return FD_ISSET(ctrl->s, &rfds); } int wpa_ctrl_get_fd(struct wpa_ctrl *ctrl) { return ctrl->s; } #endif /* CTRL_IFACE_SOCKET */ #ifdef CONFIG_CTRL_IFACE_NAMED_PIPE #ifndef WPA_SUPPLICANT_NAMED_PIPE #define WPA_SUPPLICANT_NAMED_PIPE "WpaSupplicant" #endif #define NAMED_PIPE_PREFIX TEXT("\\\\.\\pipe\\") TEXT(WPA_SUPPLICANT_NAMED_PIPE) struct wpa_ctrl * wpa_ctrl_open(const char *ctrl_path) { struct wpa_ctrl *ctrl; DWORD mode; TCHAR name[256]; int i, ret; ctrl = os_malloc(sizeof(*ctrl)); if (ctrl == NULL) return NULL; os_memset(ctrl, 0, sizeof(*ctrl)); #ifdef UNICODE if (ctrl_path == NULL) ret = _snwprintf(name, 256, NAMED_PIPE_PREFIX); else ret = _snwprintf(name, 256, NAMED_PIPE_PREFIX TEXT("-%S"), ctrl_path); #else /* UNICODE */ if (ctrl_path == NULL) ret = os_snprintf(name, 256, NAMED_PIPE_PREFIX); else ret = os_snprintf(name, 256, NAMED_PIPE_PREFIX "-%s", ctrl_path); #endif /* UNICODE */ if (os_snprintf_error(256, ret)) { os_free(ctrl); return NULL; } for (i = 0; i < 10; i++) { ctrl->pipe = CreateFile(name, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, NULL); /* * Current named pipe server side in wpa_supplicant is * re-opening the pipe for new clients only after the previous * one is taken into use. This leaves a small window for race * conditions when two connections are being opened at almost * the same time. Retry if that was the case. */ if (ctrl->pipe != INVALID_HANDLE_VALUE || GetLastError() != ERROR_PIPE_BUSY) break; WaitNamedPipe(name, 1000); } if (ctrl->pipe == INVALID_HANDLE_VALUE) { os_free(ctrl); return NULL; } mode = PIPE_READMODE_MESSAGE; if (!SetNamedPipeHandleState(ctrl->pipe, &mode, NULL, NULL)) { CloseHandle(ctrl->pipe); os_free(ctrl); return NULL; } return ctrl; } void wpa_ctrl_close(struct wpa_ctrl *ctrl) { CloseHandle(ctrl->pipe); os_free(ctrl); } int wpa_ctrl_request(struct wpa_ctrl *ctrl, const char *cmd, size_t cmd_len, char *reply, size_t *reply_len, void (*msg_cb)(char *msg, size_t len)) { DWORD written; DWORD readlen = *reply_len; if (!WriteFile(ctrl->pipe, cmd, cmd_len, &written, NULL)) return -1; if (!ReadFile(ctrl->pipe, reply, *reply_len, &readlen, NULL)) return -1; *reply_len = readlen; return 0; } int wpa_ctrl_recv(struct wpa_ctrl *ctrl, char *reply, size_t *reply_len) { DWORD len = *reply_len; if (!ReadFile(ctrl->pipe, reply, *reply_len, &len, NULL)) return -1; *reply_len = len; return 0; } int wpa_ctrl_pending(struct wpa_ctrl *ctrl) { DWORD left; if (!PeekNamedPipe(ctrl->pipe, NULL, 0, NULL, &left, NULL)) return -1; return left ? 1 : 0; } int wpa_ctrl_get_fd(struct wpa_ctrl *ctrl) { return -1; } #endif /* CONFIG_CTRL_IFACE_NAMED_PIPE */ #endif /* CONFIG_CTRL_IFACE */