/* * libwebsockets - small server side websockets and web server implementation * * Copyright (C) 2010-2013 Andy Green * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation: * version 2.1 of the License. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, * MA 02110-1301 USA */ #include "private-libwebsockets.h" #ifdef WIN32 #include #include #else #ifdef LWS_BUILTIN_GETIFADDRS #include #else #include #endif #include #include #include #endif #ifdef LWS_OPENSSL_SUPPORT extern int openssl_websocket_private_data_index; static void libwebsockets_decode_ssl_error(void) { char buf[256]; u_long err; while ((err = ERR_get_error()) != 0) { ERR_error_string_n(err, buf, sizeof(buf)); lwsl_err("*** %s\n", buf); } } #endif int interface_to_sa(const char *ifname, struct sockaddr_in *addr, size_t addrlen) { int rc = -1; #ifdef WIN32 /* TODO */ #else struct ifaddrs *ifr; struct ifaddrs *ifc; struct sockaddr_in *sin; getifaddrs(&ifr); for (ifc = ifr; ifc != NULL; ifc = ifc->ifa_next) { if (strcmp(ifc->ifa_name, ifname)) continue; if (ifc->ifa_addr == NULL) continue; sin = (struct sockaddr_in *)ifc->ifa_addr; if (sin->sin_family != AF_INET) continue; memcpy(addr, sin, addrlen); rc = 0; } freeifaddrs(ifr); #endif return rc; } struct libwebsocket * libwebsocket_create_new_server_wsi(struct libwebsocket_context *context) { struct libwebsocket *new_wsi; int n; new_wsi = (struct libwebsocket *)malloc(sizeof(struct libwebsocket)); if (new_wsi == NULL) { lwsl_err("Out of memory for new connection\n"); return NULL; } memset(new_wsi, 0, sizeof(struct libwebsocket)); #ifndef LWS_NO_EXTENSIONS new_wsi->count_active_extensions = 0; #endif new_wsi->pending_timeout = NO_PENDING_TIMEOUT; /* intialize the instance struct */ new_wsi->state = WSI_STATE_HTTP; new_wsi->u.hdr.name_buffer_pos = 0; new_wsi->mode = LWS_CONNMODE_HTTP_SERVING; for (n = 0; n < WSI_TOKEN_COUNT; n++) { new_wsi->utf8_token[n].token = NULL; new_wsi->utf8_token[n].token_len = 0; } /* * these can only be set once the protocol is known * we set an unestablished connection's protocol pointer * to the start of the supported list, so it can look * for matching ones during the handshake */ new_wsi->protocol = context->protocols; new_wsi->user_space = NULL; /* * Default protocol is 76 / 00 * After 76, there's a header specified to inform which * draft the client wants, when that's seen we modify * the individual connection's spec revision accordingly */ new_wsi->ietf_spec_revision = 0; return new_wsi; } int lws_server_socket_service(struct libwebsocket_context *context, struct libwebsocket *wsi, struct pollfd *pollfd) { unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 1 + MAX_USER_RX_BUFFER + LWS_SEND_BUFFER_POST_PADDING]; struct libwebsocket *new_wsi; int accept_fd; unsigned int clilen; struct sockaddr_in cli_addr; int n; int opt = 1; ssize_t len; #ifdef LWS_OPENSSL_SUPPORT int m; BIO *bio; #endif switch (wsi->mode) { case LWS_CONNMODE_HTTP_SERVING: /* handle http headers coming in */ /* any incoming data ready? */ if (pollfd->revents & POLLIN) { #ifdef LWS_OPENSSL_SUPPORT if (wsi->ssl) len = SSL_read(wsi->ssl, buf, sizeof buf); else #endif len = recv(pollfd->fd, buf, sizeof buf, 0); if (len < 0) { lwsl_debug("Socket read returned %d\n", len); if (errno != EINTR && errno != EAGAIN) libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); return 0; } if (!len) { libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); return 0; } n = libwebsocket_read(context, wsi, buf, len); if (n < 0) /* we closed wsi */ return 0; } /* this handles POLLOUT for http serving fragments */ if (!(pollfd->revents & POLLOUT)) break; /* one shot */ pollfd->events &= ~POLLOUT; if (wsi->state != WSI_STATE_HTTP_ISSUING_FILE) break; if (libwebsockets_serve_http_file_fragment(context, wsi) < 0) libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); else if (wsi->state == WSI_STATE_HTTP && wsi->protocol->callback) if (user_callback_handle_rxflow(wsi->protocol->callback, context, wsi, LWS_CALLBACK_HTTP_FILE_COMPLETION, wsi->user_space, wsi->u.http.filepath, wsi->u.http.filepos)) libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); break; case LWS_CONNMODE_SERVER_LISTENER: /* pollin means a client has connected to us then */ if (!(pollfd->revents & POLLIN)) break; /* listen socket got an unencrypted connection... */ clilen = sizeof(cli_addr); lws_latency_pre(context, wsi); accept_fd = accept(pollfd->fd, (struct sockaddr *)&cli_addr, &clilen); lws_latency(context, wsi, "unencrypted accept LWS_CONNMODE_SERVER_LISTENER", accept_fd, accept_fd >= 0); if (accept_fd < 0) { if (errno == EAGAIN || errno == EWOULDBLOCK) { lwsl_debug("accept asks to try again\n"); break; } lwsl_warn("ERROR on accept: %s\n", strerror(errno)); break; } /* Disable Nagle */ opt = 1; setsockopt(accept_fd, IPPROTO_TCP, TCP_NODELAY, (const void *)&opt, sizeof(opt)); /* We are nonblocking... */ fcntl(accept_fd, F_SETFL, O_NONBLOCK); /* * look at who we connected to and give user code a chance * to reject based on client IP. There's no protocol selected * yet so we issue this to protocols[0] */ if ((context->protocols[0].callback)(context, wsi, LWS_CALLBACK_FILTER_NETWORK_CONNECTION, (void *)(long)accept_fd, NULL, 0)) { lwsl_debug("Callback denied network connection\n"); compatible_close(accept_fd); break; } new_wsi = libwebsocket_create_new_server_wsi(context); if (new_wsi == NULL) { compatible_close(accept_fd); break; } new_wsi->sock = accept_fd; #ifdef LWS_OPENSSL_SUPPORT new_wsi->ssl = NULL; if (!context->use_ssl) { #endif lwsl_debug("accepted new conn port %u on fd=%d\n", ntohs(cli_addr.sin_port), accept_fd); insert_wsi_socket_into_fds(context, new_wsi); break; #ifdef LWS_OPENSSL_SUPPORT } new_wsi->ssl = SSL_new(context->ssl_ctx); if (new_wsi->ssl == NULL) { lwsl_err("SSL_new failed: %s\n", ERR_error_string(SSL_get_error( new_wsi->ssl, 0), NULL)); libwebsockets_decode_ssl_error(); free(new_wsi); compatible_close(accept_fd); break; } SSL_set_ex_data(new_wsi->ssl, openssl_websocket_private_data_index, context); SSL_set_fd(new_wsi->ssl, accept_fd); bio = SSL_get_rbio(new_wsi->ssl); if (bio) BIO_set_nbio(bio, 1); /* nonblocking */ else lwsl_notice("NULL rbio\n"); bio = SSL_get_wbio(new_wsi->ssl); if (bio) BIO_set_nbio(bio, 1); /* nonblocking */ else lwsl_notice("NULL rbio\n"); /* * we are not accepted yet, but we need to enter ourselves * as a live connection. That way we can retry when more * pieces come if we're not sorted yet */ wsi = new_wsi; wsi->mode = LWS_CONNMODE_SSL_ACK_PENDING; insert_wsi_socket_into_fds(context, wsi); libwebsocket_set_timeout(wsi, PENDING_TIMEOUT_SSL_ACCEPT, AWAITING_TIMEOUT); lwsl_info("inserted SSL acceipt into fds, trying actual SSL_accept\n"); /* fallthru */ case LWS_CONNMODE_SSL_ACK_PENDING: pollfd->events &= ~POLLOUT; /* external POLL support via protocol 0 */ context->protocols[0].callback(context, wsi, LWS_CALLBACK_CLEAR_MODE_POLL_FD, (void *)(long)wsi->sock, NULL, POLLOUT); lws_latency_pre(context, wsi); n = SSL_accept(wsi->ssl); lws_latency(context, wsi, "SSL_accept LWS_CONNMODE_SSL_ACK_PENDING\n", n, n == 1); if (n != 1) { m = SSL_get_error(wsi->ssl, n); lwsl_debug("SSL_accept failed %d / %s\n", m, ERR_error_string(m, NULL)); if (m == SSL_ERROR_WANT_READ) { context->fds[wsi->position_in_fds_table].events |= POLLIN; /* external POLL support via protocol 0 */ context->protocols[0].callback(context, wsi, LWS_CALLBACK_SET_MODE_POLL_FD, (void *)(long)wsi->sock, NULL, POLLIN); lwsl_info("SSL_ERROR_WANT_READ\n"); break; } if (m == SSL_ERROR_WANT_WRITE) { context->fds[wsi->position_in_fds_table].events |= POLLOUT; /* external POLL support via protocol 0 */ context->protocols[0].callback(context, wsi, LWS_CALLBACK_SET_MODE_POLL_FD, (void *)(long)wsi->sock, NULL, POLLOUT); break; } lwsl_debug("SSL_accept failed skt %u: %s\n", pollfd->fd, ERR_error_string(m, NULL)); libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); break; } /* OK, we are accepted */ libwebsocket_set_timeout(wsi, NO_PENDING_TIMEOUT, 0); wsi->mode = LWS_CONNMODE_HTTP_SERVING; lwsl_debug("accepted new SSL conn " "port %u on fd=%d SSL ver %s\n", ntohs(cli_addr.sin_port), SSL_get_version(wsi->ssl)); break; #endif default: break; } return 0; }