diff options
Diffstat (limited to 'src/engine/external/libwebsockets/output.c')
| -rw-r--r-- | src/engine/external/libwebsockets/output.c | 606 |
1 files changed, 606 insertions, 0 deletions
diff --git a/src/engine/external/libwebsockets/output.c b/src/engine/external/libwebsockets/output.c new file mode 100644 index 00000000..b914f281 --- /dev/null +++ b/src/engine/external/libwebsockets/output.c @@ -0,0 +1,606 @@ +/* + * libwebsockets - small server side websockets and web server implementation + * + * Copyright (C) 2010-2014 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 +libwebsocket_0405_frame_mask_generate(struct libwebsocket *wsi) +{ + int n; + + /* fetch the per-frame nonce */ + + n = libwebsockets_get_random(wsi->protocol->owning_server, + wsi->u.ws.frame_masking_nonce_04, 4); + if (n != 4) { + lwsl_parser("Unable to read from random device %s %d\n", + SYSTEM_RANDOM_FILEPATH, n); + return 1; + } + + /* 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) +{ + int n; + int m; + int start; + unsigned char *buf = (unsigned char *)vbuf; + 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 libwebsocket *wsi, unsigned char *buf, size_t len) +{ + struct libwebsocket_context *context = wsi->protocol->owning_server; + int n; + size_t real_len = len; + int m; + + if (!len) + return 0; + /* just ignore sends after we cleared the truncation buffer */ + if (wsi->state == WSI_STATE_FLUSHING_STORED_SEND_BEFORE_CLOSE && + !wsi->truncated_send_len) + return len; + + if (wsi->truncated_send_len && (buf < wsi->truncated_send_malloc || + buf > (wsi->truncated_send_malloc + + wsi->truncated_send_len + + wsi->truncated_send_offset))) { + lwsl_err("****** %x Sending new, pending truncated ...\n", wsi); + assert(0); + } + + m = lws_ext_callback_for_each_active(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 (wsi->sock < 0) + 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, n == len); + + switch (n) { + case LWS_SSL_CAPABLE_ERROR: + /* 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->truncated_send_len) { + lwsl_info("***** %x partial send moved on by %d (vs %d)\n", + wsi, n, real_len); + wsi->truncated_send_offset += n; + wsi->truncated_send_len -= n; + + if (!wsi->truncated_send_len) { + lwsl_info("***** %x partial send completed\n", wsi); + /* done with it, but don't free it */ + n = real_len; + if (wsi->state == WSI_STATE_FLUSHING_STORED_SEND_BEFORE_CLOSE) { + lwsl_info("***** %x signalling to close now\n", wsi); + return -1; /* retry closing now */ + } + } + /* always callback on writeable */ + libwebsocket_callback_on_writable( + wsi->protocol->owning_server, wsi); + + return n; + } + + if (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("***** %x 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->truncated_send_malloc || + real_len - n > wsi->truncated_send_allocation) { + lws_free(wsi->truncated_send_malloc); + + wsi->truncated_send_allocation = real_len - n; + wsi->truncated_send_malloc = lws_malloc(real_len - n); + if (!wsi->truncated_send_malloc) { + lwsl_err("truncated send: unable to malloc %d\n", + real_len - n); + return -1; + } + } + wsi->truncated_send_offset = 0; + wsi->truncated_send_len = real_len - n; + memcpy(wsi->truncated_send_malloc, buf + n, real_len - n); + + /* since something buffered, force it to get another chance to send */ + libwebsocket_callback_on_writable(wsi->protocol->owning_server, wsi); + + return real_len; +} + +/** + * libwebsocket_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 + * and an additional LWS_SEND_BUFFER_POST_PADDING bytes valid + * in the buffer after (buf + len). This is so the protocol + * header and trailer 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 libwebsocket_write(struct libwebsocket *wsi, unsigned char *buf, + size_t len, enum libwebsocket_write_protocol protocol) +{ + int n; + int pre = 0; + int post = 0; + int masked7 = wsi->mode == LWS_CONNMODE_WS_CLIENT; + unsigned char *dropmask = NULL; + unsigned char is_masked_bit = 0; + size_t orig_len = len; + struct lws_tokens eff_buf; + + if (len == 0 && protocol != LWS_WRITE_CLOSE && + protocol != LWS_WRITE_PING && protocol != LWS_WRITE_PONG) { + lwsl_warn("zero length libwebsocket_write attempt\n"); + return 0; + } + + 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 != WSI_STATE_ESTABLISHED) + return -1; + + /* if we are continuing a frame that already had its header done */ + + if (wsi->u.ws.inside_frame) + 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 (protocol) { + case LWS_WRITE_PING: + case LWS_WRITE_PONG: + case LWS_WRITE_CLOSE: + break; + default: + if (lws_ext_callback_for_each_active(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 = LWS_WS_OPCODE_07__TEXT_FRAME; + break; + case LWS_WRITE_BINARY: + n = LWS_WS_OPCODE_07__BINARY_FRAME; + break; + case LWS_WRITE_CONTINUATION: + n = LWS_WS_OPCODE_07__CONTINUATION; + break; + + case LWS_WRITE_CLOSE: + n = LWS_WS_OPCODE_07__CLOSE; + + /* + * 06+ has a 2-byte status code in network order + * we can do this because we demand post-buf + */ + + if (wsi->u.ws.close_reason) { + /* reason codes count as data bytes */ + buf -= 2; + buf[0] = wsi->u.ws.close_reason >> 8; + buf[1] = wsi->u.ws.close_reason; + len += 2; + } + break; + case LWS_WRITE_PING: + n = LWS_WS_OPCODE_07__PING; + break; + case LWS_WRITE_PONG: + n = LWS_WS_OPCODE_07__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] = len | is_masked_bit; + } else { + if (len < 65536) { + pre += 4; + buf[-pre] = n; + buf[-pre + 1] = 126 | is_masked_bit; + buf[-pre + 2] = len >> 8; + buf[-pre + 3] = 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] = len >> 24; + buf[-pre + 7] = len >> 16; + buf[-pre + 8] = len >> 8; + buf[-pre + 9] = len; + } + } + break; + } + +do_more_inside_frame: + + /* + * Deal with masking if we are in client -> server direction and + * the protocol demands it + */ + + if (wsi->mode == LWS_CONNMODE_WS_CLIENT) { + + if (!wsi->u.ws.inside_frame) + if (libwebsocket_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.frame_masking_nonce_04[ + (wsi->u.ws.frame_mask_index++) & 3]; + + /* copy the frame nonce into place */ + memcpy(dropmask, wsi->u.ws.frame_masking_nonce_04, 4); + } + } + +send_raw: + switch (protocol) { + case LWS_WRITE_CLOSE: +/* lwsl_hexdump(&buf[-pre], len + post); */ + 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 == LWS_CONNMODE_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 + post); + 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 + post); + if (n <= 0) + return n; + + if (n == len + pre + post) { + /* 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 libwebsocket_write() again with the rest + * later. + */ + + return n - (pre + post); +} + +LWS_VISIBLE int libwebsockets_serve_http_file_fragment( + struct libwebsocket_context *context, struct libwebsocket *wsi) +{ + int n; + int m; + + while (!lws_send_pipe_choked(wsi)) { + + if (wsi->truncated_send_len) { + if (lws_issue_raw(wsi, wsi->truncated_send_malloc + + wsi->truncated_send_offset, + wsi->truncated_send_len) < 0) { + lwsl_info("closing from libwebsockets_serve_http_file_fragment\n"); + return -1; + } + continue; + } + + if (wsi->u.http.filepos == wsi->u.http.filelen) + goto all_sent; + + compatible_file_read(n, wsi->u.http.fd, context->service_buffer, + sizeof(context->service_buffer)); + if (n < 0) + return -1; /* caller will close */ + if (n) { + wsi->u.http.filepos += n; + m = libwebsocket_write(wsi, context->service_buffer, 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 (compatible_file_seek_cur(wsi->u.http.fd, m - n) < 0) + return -1; + } +all_sent: + if (!wsi->truncated_send_len && + wsi->u.http.filepos == wsi->u.http.filelen) { + wsi->state = WSI_STATE_HTTP; + + if (wsi->protocol->callback) + /* ignore callback returned value */ + user_callback_handle_rxflow( + wsi->protocol->callback, context, 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"); + libwebsocket_callback_on_writable(context, wsi); + + return 0; /* indicates further processing must be done */ +} + +LWS_VISIBLE int +lws_ssl_capable_read_no_ssl(struct libwebsocket_context *context, + struct libwebsocket *wsi, unsigned char *buf, int len) +{ + int n; + + n = recv(wsi->sock, buf, len, 0); + if (n >= 0) + return n; + + lwsl_warn("error on reading from skt\n"); + return LWS_SSL_CAPABLE_ERROR; +} + +LWS_VISIBLE int +lws_ssl_capable_write_no_ssl(struct libwebsocket *wsi, unsigned char *buf, int len) +{ + int n; + + n = send(wsi->sock, buf, len, 0); + 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; + } + lwsl_debug("ERROR writing len %d to skt %d\n", len, n); + return LWS_SSL_CAPABLE_ERROR; +} |