| /* |
| * libwebsockets - small server side websockets and web server implementation |
| * |
| * Copyright (C) 2010-2015 Andy Green <andy@warmcat.com> |
| * |
| * 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" |
| |
| static int |
| lws_0405_frame_mask_generate(struct lws *wsi) |
| { |
| #if 0 |
| wsi->u.ws.mask_nonce[0] = 0; |
| wsi->u.ws.mask_nonce[1] = 0; |
| wsi->u.ws.mask_nonce[2] = 0; |
| wsi->u.ws.mask_nonce[3] = 0; |
| #else |
| int n; |
| /* fetch the per-frame nonce */ |
| |
| n = lws_get_random(lws_get_context(wsi), wsi->u.ws.mask_nonce, 4); |
| if (n != 4) { |
| lwsl_parser("Unable to read from random device %s %d\n", |
| SYSTEM_RANDOM_FILEPATH, n); |
| return 1; |
| } |
| #endif |
| /* start masking from first byte of masking key buffer */ |
| wsi->u.ws.frame_mask_index = 0; |
| |
| return 0; |
| } |
| |
| #ifdef _DEBUG |
| |
| LWS_VISIBLE void lwsl_hexdump(void *vbuf, size_t len) |
| { |
| unsigned char *buf = (unsigned char *)vbuf; |
| unsigned int n, m, start; |
| char line[80]; |
| char *p; |
| |
| lwsl_parser("\n"); |
| |
| for (n = 0; n < len;) { |
| start = n; |
| p = line; |
| |
| p += sprintf(p, "%04X: ", start); |
| |
| for (m = 0; m < 16 && n < len; m++) |
| p += sprintf(p, "%02X ", buf[n++]); |
| while (m++ < 16) |
| p += sprintf(p, " "); |
| |
| p += sprintf(p, " "); |
| |
| for (m = 0; m < 16 && (start + m) < len; m++) { |
| if (buf[start + m] >= ' ' && buf[start + m] < 127) |
| *p++ = buf[start + m]; |
| else |
| *p++ = '.'; |
| } |
| while (m++ < 16) |
| *p++ = ' '; |
| |
| *p++ = '\n'; |
| *p = '\0'; |
| lwsl_debug("%s", line); |
| } |
| lwsl_debug("\n"); |
| } |
| |
| #endif |
| |
| /* |
| * notice this returns number of bytes consumed, or -1 |
| */ |
| |
| int lws_issue_raw(struct lws *wsi, unsigned char *buf, size_t len) |
| { |
| struct lws_context *context = lws_get_context(wsi); |
| size_t real_len = len; |
| int n, m; |
| |
| if (!len) |
| return 0; |
| /* just ignore sends after we cleared the truncation buffer */ |
| if (wsi->state == LWSS_FLUSHING_STORED_SEND_BEFORE_CLOSE && |
| !wsi->trunc_len) |
| return len; |
| |
| if (wsi->trunc_len && (buf < wsi->trunc_alloc || |
| buf > (wsi->trunc_alloc + wsi->trunc_len + |
| wsi->trunc_offset))) { |
| lwsl_err("****** %x Sending new, pending truncated ...\n", wsi); |
| assert(0); |
| } |
| |
| m = lws_ext_cb_wsi_active_exts(wsi, |
| LWS_EXT_CALLBACK_PACKET_TX_DO_SEND, &buf, len); |
| if (m < 0) |
| return -1; |
| if (m) /* handled */ { |
| n = m; |
| goto handle_truncated_send; |
| } |
| |
| if (!lws_socket_is_valid(wsi->sock)) |
| lwsl_warn("** error invalid sock but expected to send\n"); |
| |
| /* nope, send it on the socket directly */ |
| lws_latency_pre(context, wsi); |
| n = lws_ssl_capable_write(wsi, buf, len); |
| lws_latency(context, wsi, "send lws_issue_raw", n, |
| (unsigned int)n == len); |
| |
| switch (n) { |
| case LWS_SSL_CAPABLE_ERROR: |
| lwsl_err("%s: wsi %p: LWS_SSL_CAPABLE_ERROR\n", __func__, |
| (void *)wsi); |
| /* we're going to close, let close know sends aren't possible */ |
| wsi->socket_is_permanently_unusable = 1; |
| return -1; |
| case LWS_SSL_CAPABLE_MORE_SERVICE: |
| /* nothing got sent, not fatal, retry the whole thing later */ |
| n = 0; |
| break; |
| } |
| |
| handle_truncated_send: |
| /* |
| * we were already handling a truncated send? |
| */ |
| if (wsi->trunc_len) { |
| lwsl_info("%p partial adv %d (vs %d)\n", wsi, n, real_len); |
| wsi->trunc_offset += n; |
| wsi->trunc_len -= n; |
| |
| if (!wsi->trunc_len) { |
| lwsl_info("***** %x partial send completed\n", wsi); |
| /* done with it, but don't free it */ |
| n = real_len; |
| if (wsi->state == LWSS_FLUSHING_STORED_SEND_BEFORE_CLOSE) { |
| lwsl_info("***** %x signalling to close now\n", wsi); |
| return -1; /* retry closing now */ |
| } |
| } |
| /* always callback on writeable */ |
| lws_callback_on_writable(wsi); |
| |
| return n; |
| } |
| |
| if ((unsigned int)n == real_len) |
| /* what we just sent went out cleanly */ |
| return n; |
| |
| if (n && wsi->u.ws.clean_buffer) |
| /* |
| * This buffer unaffected by extension rewriting. |
| * It means the user code is expected to deal with |
| * partial sends. (lws knows the header was already |
| * sent, so on next send will just resume sending |
| * payload) |
| */ |
| return n; |
| |
| /* |
| * Newly truncated send. Buffer the remainder (it will get |
| * first priority next time the socket is writable) |
| */ |
| lwsl_info("%p new partial sent %d from %d total\n", wsi, n, real_len); |
| |
| /* |
| * - if we still have a suitable malloc lying around, use it |
| * - or, if too small, reallocate it |
| * - or, if no buffer, create it |
| */ |
| if (!wsi->trunc_alloc || real_len - n > wsi->trunc_alloc_len) { |
| lws_free(wsi->trunc_alloc); |
| |
| wsi->trunc_alloc_len = real_len - n; |
| wsi->trunc_alloc = lws_malloc(real_len - n); |
| if (!wsi->trunc_alloc) { |
| lwsl_err("truncated send: unable to malloc %d\n", |
| real_len - n); |
| return -1; |
| } |
| } |
| wsi->trunc_offset = 0; |
| wsi->trunc_len = real_len - n; |
| memcpy(wsi->trunc_alloc, buf + n, real_len - n); |
| |
| /* since something buffered, force it to get another chance to send */ |
| lws_callback_on_writable(wsi); |
| |
| return real_len; |
| } |
| |
| /** |
| * lws_write() - Apply protocol then write data to client |
| * @wsi: Websocket instance (available from user callback) |
| * @buf: The data to send. For data being sent on a websocket |
| * connection (ie, not default http), this buffer MUST have |
| * LWS_SEND_BUFFER_PRE_PADDING bytes valid BEFORE the pointer. |
| * This is so the protocol header data can be added in-situ. |
| * @len: Count of the data bytes in the payload starting from buf |
| * @protocol: Use LWS_WRITE_HTTP to reply to an http connection, and one |
| * of LWS_WRITE_BINARY or LWS_WRITE_TEXT to send appropriate |
| * data on a websockets connection. Remember to allow the extra |
| * bytes before and after buf if LWS_WRITE_BINARY or LWS_WRITE_TEXT |
| * are used. |
| * |
| * This function provides the way to issue data back to the client |
| * for both http and websocket protocols. |
| * |
| * In the case of sending using websocket protocol, be sure to allocate |
| * valid storage before and after buf as explained above. This scheme |
| * allows maximum efficiency of sending data and protocol in a single |
| * packet while not burdening the user code with any protocol knowledge. |
| * |
| * Return may be -1 for a fatal error needing connection close, or a |
| * positive number reflecting the amount of bytes actually sent. This |
| * can be less than the requested number of bytes due to OS memory |
| * pressure at any given time. |
| */ |
| |
| LWS_VISIBLE int lws_write(struct lws *wsi, unsigned char *buf, |
| size_t len, enum lws_write_protocol protocol) |
| { |
| int masked7 = wsi->mode == LWSCM_WS_CLIENT; |
| unsigned char is_masked_bit = 0; |
| unsigned char *dropmask = NULL; |
| struct lws_tokens eff_buf; |
| int pre = 0, n; |
| size_t orig_len = len; |
| |
| if (protocol == LWS_WRITE_HTTP || |
| protocol == LWS_WRITE_HTTP_FINAL || |
| protocol == LWS_WRITE_HTTP_HEADERS) |
| goto send_raw; |
| |
| /* websocket protocol, either binary or text */ |
| |
| if (wsi->state != LWSS_ESTABLISHED && |
| !(wsi->state == LWSS_RETURNED_CLOSE_ALREADY && |
| protocol == LWS_WRITE_CLOSE)) |
| return -1; |
| |
| /* if we are continuing a frame that already had its header done */ |
| |
| if (wsi->u.ws.inside_frame) { |
| lwsl_debug("INSIDE FRAME\n"); |
| goto do_more_inside_frame; |
| } |
| |
| wsi->u.ws.clean_buffer = 1; |
| |
| /* |
| * give a chance to the extensions to modify payload |
| * pre-TX mangling is not allowed to truncate |
| */ |
| eff_buf.token = (char *)buf; |
| eff_buf.token_len = len; |
| |
| switch ((int)protocol) { |
| case LWS_WRITE_PING: |
| case LWS_WRITE_PONG: |
| case LWS_WRITE_CLOSE: |
| break; |
| default: |
| if (lws_ext_cb_wsi_active_exts(wsi, LWS_EXT_CALLBACK_PAYLOAD_TX, |
| &eff_buf, 0) < 0) |
| return -1; |
| } |
| |
| /* |
| * an extension did something we need to keep... for example, if |
| * compression extension, it has already updated its state according |
| * to this being issued |
| */ |
| if ((char *)buf != eff_buf.token) |
| /* |
| * extension recreated it: |
| * need to buffer this if not all sent |
| */ |
| wsi->u.ws.clean_buffer = 0; |
| |
| buf = (unsigned char *)eff_buf.token; |
| len = eff_buf.token_len; |
| |
| switch (wsi->ietf_spec_revision) { |
| case 13: |
| if (masked7) { |
| pre += 4; |
| dropmask = &buf[0 - pre]; |
| is_masked_bit = 0x80; |
| } |
| |
| switch (protocol & 0xf) { |
| case LWS_WRITE_TEXT: |
| n = LWSWSOPC_TEXT_FRAME; |
| break; |
| case LWS_WRITE_BINARY: |
| n = LWSWSOPC_BINARY_FRAME; |
| break; |
| case LWS_WRITE_CONTINUATION: |
| n = LWSWSOPC_CONTINUATION; |
| break; |
| |
| case LWS_WRITE_CLOSE: |
| n = LWSWSOPC_CLOSE; |
| break; |
| case LWS_WRITE_PING: |
| n = LWSWSOPC_PING; |
| break; |
| case LWS_WRITE_PONG: |
| n = LWSWSOPC_PONG; |
| break; |
| default: |
| lwsl_warn("lws_write: unknown write opc / protocol\n"); |
| return -1; |
| } |
| |
| if (!(protocol & LWS_WRITE_NO_FIN)) |
| n |= 1 << 7; |
| |
| if (len < 126) { |
| pre += 2; |
| buf[-pre] = n; |
| buf[-pre + 1] = (unsigned char)(len | is_masked_bit); |
| } else { |
| if (len < 65536) { |
| pre += 4; |
| buf[-pre] = n; |
| buf[-pre + 1] = 126 | is_masked_bit; |
| buf[-pre + 2] = (unsigned char)(len >> 8); |
| buf[-pre + 3] = (unsigned char)len; |
| } else { |
| pre += 10; |
| buf[-pre] = n; |
| buf[-pre + 1] = 127 | is_masked_bit; |
| #if defined __LP64__ |
| buf[-pre + 2] = (len >> 56) & 0x7f; |
| buf[-pre + 3] = len >> 48; |
| buf[-pre + 4] = len >> 40; |
| buf[-pre + 5] = len >> 32; |
| #else |
| buf[-pre + 2] = 0; |
| buf[-pre + 3] = 0; |
| buf[-pre + 4] = 0; |
| buf[-pre + 5] = 0; |
| #endif |
| buf[-pre + 6] = (unsigned char)(len >> 24); |
| buf[-pre + 7] = (unsigned char)(len >> 16); |
| buf[-pre + 8] = (unsigned char)(len >> 8); |
| buf[-pre + 9] = (unsigned char)len; |
| } |
| } |
| break; |
| } |
| |
| do_more_inside_frame: |
| |
| /* |
| * Deal with masking if we are in client -> server direction and |
| * the protocol demands it |
| */ |
| |
| if (wsi->mode == LWSCM_WS_CLIENT) { |
| if (!wsi->u.ws.inside_frame) |
| if (lws_0405_frame_mask_generate(wsi)) { |
| lwsl_err("frame mask generation failed\n"); |
| return -1; |
| } |
| |
| /* |
| * in v7, just mask the payload |
| */ |
| if (dropmask) { /* never set if already inside frame */ |
| for (n = 4; n < (int)len + 4; n++) |
| dropmask[n] = dropmask[n] ^ |
| wsi->u.ws.mask_nonce[ |
| (wsi->u.ws.frame_mask_index++) & 3]; |
| |
| /* copy the frame nonce into place */ |
| memcpy(dropmask, wsi->u.ws.mask_nonce, 4); |
| } |
| } |
| |
| send_raw: |
| switch ((int)protocol) { |
| case LWS_WRITE_CLOSE: |
| /* lwsl_hexdump(&buf[-pre], len); */ |
| case LWS_WRITE_HTTP: |
| case LWS_WRITE_HTTP_FINAL: |
| case LWS_WRITE_HTTP_HEADERS: |
| case LWS_WRITE_PONG: |
| case LWS_WRITE_PING: |
| #ifdef LWS_USE_HTTP2 |
| if (wsi->mode == LWSCM_HTTP2_SERVING) { |
| unsigned char flags = 0; |
| |
| n = LWS_HTTP2_FRAME_TYPE_DATA; |
| if (protocol == LWS_WRITE_HTTP_HEADERS) { |
| n = LWS_HTTP2_FRAME_TYPE_HEADERS; |
| flags = LWS_HTTP2_FLAG_END_HEADERS; |
| if (wsi->u.http2.send_END_STREAM) |
| flags |= LWS_HTTP2_FLAG_END_STREAM; |
| } |
| |
| if ((protocol == LWS_WRITE_HTTP || |
| protocol == LWS_WRITE_HTTP_FINAL) && |
| wsi->u.http.content_length) { |
| wsi->u.http.content_remain -= len; |
| lwsl_info("%s: content_remain = %lu\n", __func__, |
| wsi->u.http.content_remain); |
| if (!wsi->u.http.content_remain) { |
| lwsl_info("%s: selecting final write mode\n", __func__); |
| protocol = LWS_WRITE_HTTP_FINAL; |
| } |
| } |
| |
| if (protocol == LWS_WRITE_HTTP_FINAL && wsi->u.http2.END_STREAM) { |
| lwsl_info("%s: setting END_STREAM\n", __func__); |
| flags |= LWS_HTTP2_FLAG_END_STREAM; |
| } |
| |
| return lws_http2_frame_write(wsi, n, flags, |
| wsi->u.http2.my_stream_id, len, buf); |
| } |
| #endif |
| return lws_issue_raw(wsi, (unsigned char *)buf - pre, len + pre); |
| default: |
| break; |
| } |
| |
| wsi->u.ws.inside_frame = 1; |
| |
| /* |
| * give any active extensions a chance to munge the buffer |
| * before send. We pass in a pointer to an lws_tokens struct |
| * prepared with the default buffer and content length that's in |
| * there. Rather than rewrite the default buffer, extensions |
| * that expect to grow the buffer can adapt .token to |
| * point to their own per-connection buffer in the extension |
| * user allocation. By default with no extensions or no |
| * extension callback handling, just the normal input buffer is |
| * used then so it is efficient. |
| * |
| * callback returns 1 in case it wants to spill more buffers |
| * |
| * This takes care of holding the buffer if send is incomplete, ie, |
| * if wsi->u.ws.clean_buffer is 0 (meaning an extension meddled with |
| * the buffer). If wsi->u.ws.clean_buffer is 1, it will instead |
| * return to the user code how much OF THE USER BUFFER was consumed. |
| */ |
| |
| n = lws_issue_raw_ext_access(wsi, buf - pre, len + pre); |
| if (n <= 0) |
| return n; |
| |
| if (n == (int)len + pre) { |
| /* everything in the buffer was handled (or rebuffered...) */ |
| wsi->u.ws.inside_frame = 0; |
| return orig_len; |
| } |
| |
| /* |
| * it is how many bytes of user buffer got sent... may be < orig_len |
| * in which case callback when writable has already been arranged |
| * and user code can call lws_write() again with the rest |
| * later. |
| */ |
| |
| return n - pre; |
| } |
| |
| LWS_VISIBLE int lws_serve_http_file_fragment(struct lws *wsi) |
| { |
| struct lws_context *context = wsi->context; |
| unsigned long amount; |
| int n, m; |
| |
| while (!lws_send_pipe_choked(wsi)) { |
| if (wsi->trunc_len) { |
| if (lws_issue_raw(wsi, wsi->trunc_alloc + |
| wsi->trunc_offset, |
| wsi->trunc_len) < 0) { |
| lwsl_info("%s: closing\n", __func__); |
| return -1; |
| } |
| continue; |
| } |
| |
| if (wsi->u.http.filepos == wsi->u.http.filelen) |
| goto all_sent; |
| |
| if (lws_plat_file_read(wsi, wsi->u.http.fd, &amount, |
| context->serv_buf, |
| sizeof(context->serv_buf)) < 0) |
| return -1; /* caller will close */ |
| |
| n = (int)amount; |
| if (n) { |
| lws_set_timeout(wsi, PENDING_TIMEOUT_HTTP_CONTENT, |
| AWAITING_TIMEOUT); |
| wsi->u.http.filepos += n; |
| m = lws_write(wsi, context->serv_buf, n, |
| wsi->u.http.filepos == wsi->u.http.filelen ? |
| LWS_WRITE_HTTP_FINAL : LWS_WRITE_HTTP); |
| if (m < 0) |
| return -1; |
| |
| if (m != n) |
| /* adjust for what was not sent */ |
| if (lws_plat_file_seek_cur(wsi, wsi->u.http.fd, |
| m - n) == |
| (unsigned long)-1) |
| return -1; |
| } |
| all_sent: |
| if (!wsi->trunc_len && wsi->u.http.filepos == wsi->u.http.filelen) { |
| wsi->state = LWSS_HTTP; |
| |
| /* we might be in keepalive, so close it off here */ |
| lws_plat_file_close(wsi, wsi->u.http.fd); |
| wsi->u.http.fd = LWS_INVALID_FILE; |
| |
| if (wsi->protocol->callback) |
| /* ignore callback returned value */ |
| user_callback_handle_rxflow( |
| wsi->protocol->callback, wsi, |
| LWS_CALLBACK_HTTP_FILE_COMPLETION, |
| wsi->user_space, NULL, 0); |
| return 1; /* >0 indicates completed */ |
| } |
| } |
| |
| lwsl_info("choked before able to send whole file (post)\n"); |
| lws_callback_on_writable(wsi); |
| |
| return 0; /* indicates further processing must be done */ |
| } |
| |
| #if LWS_POSIX |
| LWS_VISIBLE int |
| lws_ssl_capable_read_no_ssl(struct lws *wsi, unsigned char *buf, int len) |
| { |
| int n; |
| |
| n = recv(wsi->sock, (char *)buf, len, 0); |
| if (n >= 0) |
| return n; |
| #if LWS_POSIX |
| if (LWS_ERRNO == LWS_EAGAIN || |
| LWS_ERRNO == LWS_EWOULDBLOCK || |
| LWS_ERRNO == LWS_EINTR) |
| return LWS_SSL_CAPABLE_MORE_SERVICE; |
| #endif |
| lwsl_warn("error on reading from skt\n"); |
| return LWS_SSL_CAPABLE_ERROR; |
| } |
| |
| LWS_VISIBLE int |
| lws_ssl_capable_write_no_ssl(struct lws *wsi, unsigned char *buf, int len) |
| { |
| int n = 0; |
| |
| #if LWS_POSIX |
| n = send(wsi->sock, (char *)buf, len, MSG_NOSIGNAL); |
| if (n >= 0) |
| return n; |
| |
| if (LWS_ERRNO == LWS_EAGAIN || |
| LWS_ERRNO == LWS_EWOULDBLOCK || |
| LWS_ERRNO == LWS_EINTR) { |
| if (LWS_ERRNO == LWS_EWOULDBLOCK) |
| lws_set_blocking_send(wsi); |
| |
| return LWS_SSL_CAPABLE_MORE_SERVICE; |
| } |
| #else |
| (void)n; |
| (void)wsi; |
| (void)buf; |
| (void)len; |
| // !!! |
| #endif |
| |
| lwsl_debug("ERROR writing len %d to skt %d\n", len, n); |
| return LWS_SSL_CAPABLE_ERROR; |
| } |
| #endif |
| LWS_VISIBLE int |
| lws_ssl_pending_no_ssl(struct lws *wsi) |
| { |
| (void)wsi; |
| return 0; |
| } |