/* Copyright (c) 2003-2014, Arvid Norberg All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. * Neither the name of the author nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include #include #include #include #include "libtorrent/web_peer_connection.hpp" #include "libtorrent/session.hpp" #include "libtorrent/identify_client.hpp" #include "libtorrent/entry.hpp" #include "libtorrent/bencode.hpp" #include "libtorrent/alert_types.hpp" #include "libtorrent/invariant_check.hpp" #include "libtorrent/io.hpp" #include "libtorrent/version.hpp" #include "libtorrent/aux_/session_impl.hpp" #include "libtorrent/parse_url.hpp" #include "libtorrent/peer_info.hpp" using boost::shared_ptr; using libtorrent::aux::session_impl; namespace libtorrent { enum { request_size_overhead = 5000 }; web_peer_connection::web_peer_connection( session_impl& ses , boost::weak_ptr t , boost::shared_ptr s , tcp::endpoint const& remote , web_seed_entry& web) : web_connection_base(ses, t, s, remote, web) , m_url(web.url) , m_web(web) , m_received_body(0) , m_range_pos(0) , m_block_pos(0) , m_chunk_pos(0) , m_partial_chunk_header(0) , m_num_responses(0) { INVARIANT_CHECK; if (!ses.settings().report_web_seed_downloads) ignore_stats(true); shared_ptr tor = t.lock(); TORRENT_ASSERT(tor); // we always prefer downloading 1 MiB chunks // from web seeds, or whole pieces if pieces // are larger than a MiB int preferred_size = 1024 * 1024; // if the web server is known not to support keep-alive. // request even larger blocks at a time if (!web.supports_keepalive) preferred_size *= 4; prefer_whole_pieces((std::max)(preferred_size / tor->torrent_file().piece_length(), 1)); // we want large blocks as well, so // we can request more bytes at once // this setting will merge adjacent requests // into single larger ones request_large_blocks(true); #ifdef TORRENT_VERBOSE_LOGGING peer_log("*** web_peer_connection %s", web.url.c_str()); #endif } void web_peer_connection::on_connected() { incoming_have_all(); if (m_web.restart_request.piece != -1) { // increase the chances of requesting the block // we have partial data for already, to finish it incoming_suggest(m_web.restart_request.piece); } web_connection_base::on_connected(); } void web_peer_connection::disconnect(error_code const& ec, int error) { if (is_disconnecting()) return; boost::shared_ptr t = associated_torrent().lock(); if (!m_requests.empty() && !m_file_requests.empty() && !m_piece.empty()) { #if 0 std::cerr << this << " SAVE-RESTART-DATA: data: " << m_piece.size() << " req: " << m_requests.front().piece << " off: " << m_requests.front().start << std::endl; #endif m_web.restart_request = m_requests.front(); if (!m_web.restart_piece.empty()) { // we're about to replace a different restart piece // buffer. So it was wasted download if (t) t->add_redundant_bytes(m_web.restart_piece.size() , torrent::piece_closing); } m_web.restart_piece.swap(m_piece); // we have to do this to not count this data as redundant. The // upper layer will call downloading_piece_progress and assume // it's all wasted download. Since we're saving it here, it isn't. m_requests.clear(); m_block_pos = 0; } if (!m_web.supports_keepalive && error == 0) { // if the web server doesn't support keepalive and we were // disconnected as a graceful EOF, reconnect right away if (t) t->session().m_io_service.post( boost::bind(&torrent::maybe_connect_web_seeds, t)); } peer_connection::disconnect(ec, error); if (t) t->disconnect_web_seed(this); } boost::optional web_peer_connection::downloading_piece_progress() const { if (m_requests.empty()) return boost::optional(); boost::shared_ptr t = associated_torrent().lock(); TORRENT_ASSERT(t); piece_block_progress ret; ret.piece_index = m_requests.front().piece; ret.bytes_downloaded = m_block_pos % t->block_size(); // this is used to make sure that the block_index stays within // bounds. If the entire piece is downloaded, the block_index // would otherwise point to one past the end int correction = m_block_pos ? -1 : 0; ret.block_index = (m_requests.front().start + m_block_pos + correction) / t->block_size(); TORRENT_ASSERT(ret.block_index < int(piece_block::invalid.block_index)); TORRENT_ASSERT(ret.piece_index < int(piece_block::invalid.piece_index)); ret.full_block_bytes = t->block_size(); const int last_piece = t->torrent_file().num_pieces() - 1; if (ret.piece_index == last_piece && ret.block_index == t->torrent_file().piece_size(last_piece) / t->block_size()) ret.full_block_bytes = t->torrent_file().piece_size(last_piece) % t->block_size(); return ret; } void web_peer_connection::write_request(peer_request const& r) { INVARIANT_CHECK; boost::shared_ptr t = associated_torrent().lock(); TORRENT_ASSERT(t); TORRENT_ASSERT(t->valid_metadata()); bool single_file_request = t->torrent_file().num_files() == 1; if (!single_file_request) { // handle incorrect .torrent files which are multi-file // but have web seeds not ending with a slash if (m_path.empty() || m_path[m_path.size() - 1] != '/') m_path += "/"; if (m_url.empty() || m_url[m_url.size() - 1] != '/') m_url += "/"; } else { // handle .torrent files that don't include the filename in the url if (m_path.empty()) m_path += "/" + t->torrent_file().name(); else if (m_path[m_path.size() - 1] == '/') { std::string tmp = t->torrent_file().files().at(0).path; #ifdef TORRENT_WINDOWS convert_path_to_posix(tmp); #endif m_path += tmp; } else if (!m_url.empty() && m_url[m_url.size() - 1] == '/') { std::string tmp = t->torrent_file().files().at(0).path; #ifdef TORRENT_WINDOWS convert_path_to_posix(tmp); #endif m_url += tmp; } } torrent_info const& info = t->torrent_file(); peer_request req = r; std::string request; request.reserve(400); int size = r.length; const int block_size = t->block_size(); const int piece_size = t->torrent_file().piece_length(); peer_request pr; while (size > 0) { int request_offset = r.start + r.length - size; pr.start = request_offset % piece_size; pr.length = (std::min)(block_size, size); pr.piece = r.piece + request_offset / piece_size; m_requests.push_back(pr); size -= pr.length; if (m_web.restart_request == m_requests.front()) { m_piece.swap(m_web.restart_piece); m_block_pos += m_piece.size(); peer_request& front = m_requests.front(); TORRENT_ASSERT(front.length > int(m_piece.size())); #if 0 std::cerr << this << " RESTART-DATA: data: " << m_piece.size() << " req: ( " << front.piece << ", " << front.start << ", " << (front.start + front.length - 1) << ")" << std::endl; #endif req.start += m_piece.size(); req.length -= m_piece.size(); // just to keep the accounting straight for the upper layer. // it doesn't know we just re-wrote the request incoming_piece_fragment(m_piece.size()); m_web.restart_request.piece = -1; } #if 0 std::cerr << this << " REQ: p: " << pr.piece << " " << pr.start << std::endl; #endif } proxy_settings const& ps = m_ses.proxy(); bool using_proxy = (ps.type == proxy_settings::http || ps.type == proxy_settings::http_pw) && !m_ssl; if (single_file_request) { request += "GET "; // do not encode single file paths, they are // assumed to be encoded in the torrent file request += using_proxy ? m_url : m_path; request += " HTTP/1.1\r\n"; add_headers(request, ps, using_proxy); request += "\r\nRange: bytes="; request += to_string(size_type(req.piece) * info.piece_length() + req.start).elems; request += "-"; request += to_string(size_type(req.piece) * info.piece_length() + req.start + req.length - 1).elems; request += "\r\n\r\n"; m_first_request = false; m_file_requests.push_back(0); } else { std::vector files = info.orig_files().map_block( req.piece, req.start, req.length); for (std::vector::iterator i = files.begin(); i != files.end(); ++i) { file_slice const& f = *i; if (info.orig_files().pad_file_at(f.file_index)) { m_file_requests.push_back(f.file_index); continue; } request += "GET "; if (using_proxy) { // m_url is already a properly escaped URL // with the correct slashes. Don't encode it again request += m_url; std::string path = info.orig_files().file_path(f.file_index); #ifdef TORRENT_WINDOWS convert_path_to_posix(path); #endif request += escape_path(path.c_str(), path.length()); } else { // m_path is already a properly escaped URL // with the correct slashes. Don't encode it again request += m_path; std::string path = info.orig_files().file_path(f.file_index); #ifdef TORRENT_WINDOWS convert_path_to_posix(path); #endif request += escape_path(path.c_str(), path.length()); } request += " HTTP/1.1\r\n"; add_headers(request, ps, using_proxy); request += "\r\nRange: bytes="; request += to_string(f.offset).elems; request += "-"; request += to_string(f.offset + f.size - 1).elems; request += "\r\n\r\n"; m_first_request = false; #if 0 std::cerr << this << " SEND-REQUEST: f: " << f.file_index << " s: " << f.offset << " e: " << (f.offset + f.size - 1) << std::endl; #endif TORRENT_ASSERT(f.file_index >= 0); m_file_requests.push_back(f.file_index); } } #ifdef TORRENT_VERBOSE_LOGGING peer_log("==> %s", request.c_str()); #endif // in case the first file on this series of requests is a padfile // we need to handle it right now, and pretend that we got a response // with zeros. buffer::const_interval recv_buffer = receive_buffer(); handle_padfile(recv_buffer); if (associated_torrent().expired()) return; send_buffer(request.c_str(), request.size(), message_type_request); } // -------------------------- // RECEIVE DATA // -------------------------- namespace { bool range_contains(peer_request const& range, peer_request const& req, int piece_size) { size_type range_start = size_type(range.piece) * piece_size + range.start; size_type req_start = size_type(req.piece) * piece_size + req.start; return range_start <= req_start && range_start + range.length >= req_start + req.length; } } bool web_peer_connection::maybe_harvest_block() { peer_request const& front_request = m_requests.front(); if (int(m_piece.size()) < front_request.length) return false; TORRENT_ASSERT(int(m_piece.size()) == front_request.length); // each call to incoming_piece() may result in us becoming // a seed. If we become a seed, all seeds we're connected to // will be disconnected, including this web seed. We need to // check for the disconnect condition after the call. boost::shared_ptr t = associated_torrent().lock(); TORRENT_ASSERT(t); buffer::const_interval recv_buffer = receive_buffer(); incoming_piece(front_request, &m_piece[0]); m_requests.pop_front(); if (associated_torrent().expired()) return false; TORRENT_ASSERT(m_block_pos >= front_request.length); m_block_pos -= front_request.length; cut_receive_buffer(m_body_start, t->block_size() + request_size_overhead); m_body_start = 0; recv_buffer = receive_buffer(); // TORRENT_ASSERT(m_received_body <= range_end - range_start); m_piece.clear(); TORRENT_ASSERT(m_piece.empty()); return true; } bool web_peer_connection::received_invalid_data(int index, bool single_peer) { if (!single_peer) return peer_connection::received_invalid_data(index, single_peer); // when a web seed fails a hash check, do the following: // 1. if the whole piece only overlaps a single file, mark that file as not // have for this peer // 2. if the piece overlaps more than one file, mark the piece as not have // for this peer // 3. if it's a single file torrent, just ban it right away // this handles the case where web seeds may have some files updated but not other boost::shared_ptr t = associated_torrent().lock(); file_storage const& fs = t->torrent_file().files(); // single file torrent if (fs.num_files() == 1) return peer_connection::received_invalid_data(index, single_peer); std::vector files = fs.map_block(index, 0, fs.piece_size(index)); if (files.size() == 1) { // assume the web seed has a different copy of this specific file // than what we expect, and pretend not to have it. int fi = files[0].file_index; int first_piece = int(fs.file_offset(fi) / fs.piece_length()); // one past last piece int end_piece = int((fs.file_offset(fi) + fs.file_size(fi) + 1) / fs.piece_length()); for (int i = first_piece; i < end_piece; ++i) incoming_dont_have(i); } else { incoming_dont_have(index); } peer_connection::received_invalid_data(index, single_peer); // if we don't think we have any of the files, allow banning the web seed if (num_have_pieces() == 0) return true; // don't disconnect, we won't request anything from this file again return false; } void web_peer_connection::on_receive(error_code const& error , std::size_t bytes_transferred) { INVARIANT_CHECK; #ifdef TORRENT_DEBUG TORRENT_ASSERT(m_statistics.last_payload_downloaded() + m_statistics.last_protocol_downloaded() + bytes_transferred < size_t(INT_MAX)); int dl_target = m_statistics.last_payload_downloaded() + m_statistics.last_protocol_downloaded() + bytes_transferred; #endif if (error) { m_statistics.received_bytes(0, bytes_transferred); #ifdef TORRENT_VERBOSE_LOGGING peer_log("*** web_peer_connection error: %s", error.message().c_str()); #endif #ifdef TORRENT_DEBUG TORRENT_ASSERT(m_statistics.last_payload_downloaded() + m_statistics.last_protocol_downloaded() == dl_target); #endif return; } boost::shared_ptr t = associated_torrent().lock(); TORRENT_ASSERT(t); for (;;) { #ifdef TORRENT_DEBUG TORRENT_ASSERT(m_statistics.last_payload_downloaded() + m_statistics.last_protocol_downloaded() + int(bytes_transferred) == dl_target); #endif buffer::const_interval recv_buffer = receive_buffer(); int payload; int protocol; bool header_finished = m_parser.header_finished(); if (!header_finished) { bool failed = false; boost::tie(payload, protocol) = m_parser.incoming(recv_buffer, failed); m_statistics.received_bytes(0, protocol); TORRENT_ASSERT(int(bytes_transferred) >= protocol); bytes_transferred -= protocol; if (failed) { m_statistics.received_bytes(0, bytes_transferred); #ifdef TORRENT_VERBOSE_LOGGING peer_log("*** %s", std::string(recv_buffer.begin, recv_buffer.end).c_str()); #endif disconnect(errors::http_parse_error, 2); #ifdef TORRENT_DEBUG TORRENT_ASSERT(m_statistics.last_payload_downloaded() + m_statistics.last_protocol_downloaded() == dl_target); #endif return; } TORRENT_ASSERT(recv_buffer.left() == 0 || *recv_buffer.begin == 'H'); TORRENT_ASSERT(recv_buffer.left() <= packet_size()); // this means the entire status line hasn't been received yet if (m_parser.status_code() == -1) { TORRENT_ASSERT(payload == 0); TORRENT_ASSERT(bytes_transferred == 0); #ifdef TORRENT_DEBUG TORRENT_ASSERT(m_statistics.last_payload_downloaded() + m_statistics.last_protocol_downloaded() + int(bytes_transferred) == dl_target); #endif break; } if (!m_parser.header_finished()) { TORRENT_ASSERT(payload == 0); TORRENT_ASSERT(bytes_transferred == 0); #ifdef TORRENT_DEBUG TORRENT_ASSERT(m_statistics.last_payload_downloaded() + m_statistics.last_protocol_downloaded() + int(bytes_transferred) == dl_target); #endif break; } m_body_start = m_parser.body_start(); m_received_body = 0; } // we just completed reading the header if (!header_finished) { ++m_num_responses; if (m_parser.connection_close()) { incoming_choke(); if (m_num_responses == 1) m_web.supports_keepalive = false; } #ifdef TORRENT_VERBOSE_LOGGING peer_log("*** STATUS: %d %s", m_parser.status_code(), m_parser.message().c_str()); std::multimap const& headers = m_parser.headers(); for (std::multimap::const_iterator i = headers.begin() , end(headers.end()); i != end; ++i) peer_log(" %s: %s", i->first.c_str(), i->second.c_str()); #endif // if the status code is not one of the accepted ones, abort if (!is_ok_status(m_parser.status_code())) { // TODO: 3 just make this peer not have the pieces // associated with the file we just requested. Only // when it doesn't have any of the file do the following int retry_time = atoi(m_parser.header("retry-after").c_str()); if (retry_time <= 0) retry_time = m_ses.settings().urlseed_wait_retry; // temporarily unavailable, retry later t->retry_web_seed(this, retry_time); std::string error_msg = to_string(m_parser.status_code()).elems + (" " + m_parser.message()); if (m_ses.m_alerts.should_post()) { m_ses.m_alerts.post_alert(url_seed_alert(t->get_handle(), m_url , error_msg)); } m_statistics.received_bytes(0, bytes_transferred); disconnect(error_code(m_parser.status_code(), get_http_category()), 1); #ifdef TORRENT_DEBUG TORRENT_ASSERT(m_statistics.last_payload_downloaded() + m_statistics.last_protocol_downloaded() == dl_target); #endif return; } if (is_redirect(m_parser.status_code())) { // this means we got a redirection request // look for the location header std::string location = m_parser.header("location"); m_statistics.received_bytes(0, bytes_transferred); if (location.empty()) { // we should not try this server again. t->remove_web_seed(this); disconnect(errors::missing_location, 2); #ifdef TORRENT_DEBUG TORRENT_ASSERT(m_statistics.last_payload_downloaded() + m_statistics.last_protocol_downloaded() == dl_target); #endif return; } bool single_file_request = false; if (!m_path.empty() && m_path[m_path.size() - 1] != '/') single_file_request = true; // add the redirected url and remove the current one if (!single_file_request) { TORRENT_ASSERT(!m_file_requests.empty()); int file_index = m_file_requests.front(); // TODO: 2 create a mapping of file-index to redirection URLs. Use that to form // URLs instead. Support to reconnect to a new server without destructing this // peer_connection torrent_info const& info = t->torrent_file(); std::string path = info.orig_files().file_path(file_index); #ifdef TORRENT_WINDOWS convert_path_to_posix(path); #endif path = escape_path(path.c_str(), path.length()); size_t i = location.rfind(path); if (i == std::string::npos) { t->remove_web_seed(this); disconnect(errors::invalid_redirection, 2); #ifdef TORRENT_DEBUG TORRENT_ASSERT(m_statistics.last_payload_downloaded() + m_statistics.last_protocol_downloaded() == dl_target); #endif return; } location.resize(i); } t->add_web_seed(location, web_seed_entry::url_seed, m_external_auth, m_extra_headers); t->remove_web_seed(this); disconnect(errors::redirecting, 2); #ifdef TORRENT_DEBUG TORRENT_ASSERT(m_statistics.last_payload_downloaded() + m_statistics.last_protocol_downloaded() == dl_target); #endif return; } std::string const& server_version = m_parser.header("server"); if (!server_version.empty()) { m_server_string = "URL seed @ "; m_server_string += m_host; m_server_string += " ("; m_server_string += server_version; m_server_string += ")"; } m_body_start = m_parser.body_start(); m_received_body = 0; m_range_pos = 0; } recv_buffer.begin += m_body_start; // we only received the header, no data if (recv_buffer.left() == 0) { #ifdef TORRENT_DEBUG TORRENT_ASSERT(m_statistics.last_payload_downloaded() + m_statistics.last_protocol_downloaded() == dl_target); #endif break; } size_type range_start; size_type range_end; if (m_parser.status_code() == 206) { boost::tie(range_start, range_end) = m_parser.content_range(); if (range_start < 0 || range_end < range_start) { m_statistics.received_bytes(0, bytes_transferred); // we should not try this server again. t->remove_web_seed(this); disconnect(errors::invalid_range); #ifdef TORRENT_DEBUG TORRENT_ASSERT(m_statistics.last_payload_downloaded() + m_statistics.last_protocol_downloaded() == dl_target); #endif return; } // the http range is inclusive range_end++; } else { range_start = 0; range_end = m_parser.content_length(); if (range_end == -1) { m_statistics.received_bytes(0, bytes_transferred); // we should not try this server again. t->remove_web_seed(this); disconnect(errors::no_content_length, 2); #ifdef TORRENT_DEBUG TORRENT_ASSERT(m_statistics.last_payload_downloaded() + m_statistics.last_protocol_downloaded() == dl_target); #endif return; } } // ========================= // === CHUNKED ENCODING === // ========================= while (m_parser.chunked_encoding() && m_chunk_pos >= 0 && m_chunk_pos < recv_buffer.left()) { int header_size = 0; size_type chunk_size = 0; buffer::const_interval chunk_start = recv_buffer; chunk_start.begin += m_chunk_pos; TORRENT_ASSERT(chunk_start.begin[0] == '\r' || is_hex(chunk_start.begin, 1)); bool ret = m_parser.parse_chunk_header(chunk_start, &chunk_size, &header_size); if (!ret) { TORRENT_ASSERT(int(bytes_transferred) >= chunk_start.left() - m_partial_chunk_header); bytes_transferred -= chunk_start.left() - m_partial_chunk_header; m_statistics.received_bytes(0, chunk_start.left() - m_partial_chunk_header); m_partial_chunk_header = chunk_start.left(); if (bytes_transferred == 0) return; break; } else { #ifdef TORRENT_VERBOSE_LOGGING peer_log("*** parsed chunk: %d header_size: %d", chunk_size, header_size); #endif TORRENT_ASSERT(int(bytes_transferred) >= header_size - m_partial_chunk_header); bytes_transferred -= header_size - m_partial_chunk_header; m_statistics.received_bytes(0, header_size - m_partial_chunk_header); m_partial_chunk_header = 0; TORRENT_ASSERT(chunk_size != 0 || chunk_start.left() <= header_size || chunk_start.begin[header_size] == 'H'); // cut out the chunk header from the receive buffer TORRENT_ASSERT(m_body_start + m_chunk_pos < INT_MAX); cut_receive_buffer(header_size, t->block_size() + request_size_overhead, int(m_body_start + m_chunk_pos)); recv_buffer = receive_buffer(); recv_buffer.begin += m_body_start; m_chunk_pos += chunk_size; if (chunk_size == 0) { #ifdef TORRENT_DEBUG chunk_start = recv_buffer; chunk_start.begin += m_chunk_pos; TORRENT_ASSERT(chunk_start.left() == 0 || chunk_start.begin[0] == 'H'); #endif m_chunk_pos = -1; } // if all of hte receive buffer was just consumed as chunk // header, we're done if (bytes_transferred == 0) return; } } if (m_requests.empty() || m_file_requests.empty()) { m_statistics.received_bytes(0, bytes_transferred); disconnect(errors::http_error, 2); #ifdef TORRENT_DEBUG TORRENT_ASSERT(m_statistics.last_payload_downloaded() + m_statistics.last_protocol_downloaded() == dl_target); #endif return; } size_type left_in_response = range_end - range_start - m_range_pos; int payload_transferred = int((std::min)(left_in_response, size_type(bytes_transferred))); torrent_info const& info = t->torrent_file(); peer_request front_request = m_requests.front(); TORRENT_ASSERT(m_block_pos >= 0); #ifdef TORRENT_VERBOSE_LOGGING peer_log("*** payload_transferred: %d [ %d:%d = %d ]" , payload_transferred, front_request.piece , front_request.start, front_request.length); #endif m_statistics.received_bytes(payload_transferred, 0); TORRENT_ASSERT(int(bytes_transferred) >= payload_transferred); bytes_transferred -= payload_transferred; m_range_pos += payload_transferred; m_block_pos += payload_transferred; if (m_range_pos > range_end - range_start) m_range_pos = range_end - range_start; int file_index = m_file_requests.front(); peer_request in_range = info.orig_files().map_file(file_index, range_start , int(range_end - range_start)); // request start size_type rs = size_type(in_range.piece) * info.piece_length() + in_range.start; // request end size_type re = rs + in_range.length; // file start size_type fs = size_type(front_request.piece) * info.piece_length() + front_request.start; // the http response body consists of 3 parts // 1. the middle of a block or the ending of a block // 2. a number of whole blocks // 3. the start of a block // in that order, these parts are parsed. bool range_overlaps_request = re >= fs + int(m_piece.size()); if (!range_overlaps_request) { incoming_piece_fragment((std::min)(payload_transferred , front_request.length - m_block_pos)); m_statistics.received_bytes(0, bytes_transferred); // this means the end of the incoming request ends _before_ the // first expected byte (fs + m_piece.size()) disconnect(errors::invalid_range, 2); return; } // if the request is contained in the range (i.e. the entire request // fits in the range) we should not start a partial piece, since we soon // will receive enough to call incoming_piece() and pass the read buffer // directly (in the next loop below). if (range_overlaps_request && !range_contains(in_range, front_request, info.piece_length())) { // the start of the next block to receive is stored // in m_piece. We need to append the rest of that // block from the http receive buffer and then // (if it completed) call incoming_piece() with // m_piece as buffer. int piece_size = int(m_piece.size()); int copy_size = (std::min)((std::min)(front_request.length - piece_size , recv_buffer.left()), int(range_end - range_start - m_received_body)); if (copy_size > m_chunk_pos && m_chunk_pos > 0) copy_size = m_chunk_pos; if (copy_size > 0) { TORRENT_ASSERT(int(m_piece.size()) == m_received_in_piece); m_piece.resize(piece_size + copy_size); std::memcpy(&m_piece[0] + piece_size, recv_buffer.begin, copy_size); TORRENT_ASSERT(int(m_piece.size()) <= front_request.length); recv_buffer.begin += copy_size; m_received_body += copy_size; m_body_start += copy_size; if (m_chunk_pos > 0) { TORRENT_ASSERT(m_chunk_pos >= copy_size); m_chunk_pos -= copy_size; } TORRENT_ASSERT(m_received_body <= range_end - range_start); TORRENT_ASSERT(int(m_piece.size()) <= front_request.length); incoming_piece_fragment(copy_size); TORRENT_ASSERT(int(m_piece.size()) == m_received_in_piece); } if (maybe_harvest_block()) recv_buffer = receive_buffer(); if (associated_torrent().expired()) return; } // report all received blocks to the bittorrent engine while (!m_requests.empty() && range_contains(in_range, m_requests.front(), info.piece_length()) && m_block_pos >= m_requests.front().length) { peer_request r = m_requests.front(); TORRENT_ASSERT(recv_buffer.left() >= r.length); incoming_piece_fragment(r.length); incoming_piece(r, recv_buffer.begin); m_requests.pop_front(); if (associated_torrent().expired()) return; TORRENT_ASSERT(m_block_pos >= r.length); m_block_pos -= r.length; m_received_body += r.length; TORRENT_ASSERT(receive_buffer().begin + m_body_start == recv_buffer.begin); TORRENT_ASSERT(m_received_body <= range_end - range_start); cut_receive_buffer(m_body_start + r.length, t->block_size() + request_size_overhead); if (m_chunk_pos > 0) { TORRENT_ASSERT(m_chunk_pos >= r.length); m_chunk_pos -= r.length; } m_body_start = 0; recv_buffer = receive_buffer(); } if (!m_requests.empty()) { if (in_range.start + in_range.length < m_requests.front().start + m_requests.front().length && (m_received_body + recv_buffer.left() >= range_end - range_start)) { int piece_size = int(m_piece.size()); int copy_size = (std::min)((std::min)(m_requests.front().length - piece_size , recv_buffer.left()), int(range_end - range_start - m_received_body)); TORRENT_ASSERT(copy_size >= 0); if (copy_size > 0) { TORRENT_ASSERT(int(m_piece.size()) == m_received_in_piece); m_piece.resize(piece_size + copy_size); std::memcpy(&m_piece[0] + piece_size, recv_buffer.begin, copy_size); recv_buffer.begin += copy_size; m_received_body += copy_size; m_body_start += copy_size; incoming_piece_fragment(copy_size); TORRENT_ASSERT(int(m_piece.size()) == m_received_in_piece); } TORRENT_ASSERT(m_received_body == range_end - range_start); } } TORRENT_ASSERT(m_received_body <= range_end - range_start); // if we're in chunked encoding mode, we have to wait for the complete // tail header before we can consider have received the block, otherwise // we'll get out of sync with the next http response. m_chunk_pos is set // to -1 when the tail header has been received if (m_received_body == range_end - range_start && (!m_parser.chunked_encoding() || m_chunk_pos == -1)) { int size_to_cut = recv_buffer.begin - receive_buffer().begin; TORRENT_ASSERT(receive_buffer().left() < size_to_cut + 1 || receive_buffer()[size_to_cut] == 'H'); cut_receive_buffer(size_to_cut, t->block_size() + request_size_overhead); if (m_chunk_pos > 0) { TORRENT_ASSERT(m_chunk_pos >= size_to_cut); m_chunk_pos -= size_to_cut; } recv_buffer = receive_buffer(); m_file_requests.pop_front(); m_parser.reset(); m_body_start = 0; m_received_body = 0; m_chunk_pos = 0; m_partial_chunk_header = 0; handle_padfile(recv_buffer); if (associated_torrent().expired()) return; continue; } if (bytes_transferred == 0 || payload_transferred == 0) { #ifdef TORRENT_DEBUG TORRENT_ASSERT(m_statistics.last_payload_downloaded() + m_statistics.last_protocol_downloaded() == dl_target); #endif break; } TORRENT_ASSERT(payload_transferred > 0); } TORRENT_ASSERT(bytes_transferred == 0); #ifdef TORRENT_DEBUG TORRENT_ASSERT(m_statistics.last_payload_downloaded() + m_statistics.last_protocol_downloaded() == dl_target); #endif } void web_peer_connection::get_specific_peer_info(peer_info& p) const { web_connection_base::get_specific_peer_info(p); p.flags |= peer_info::local_connection; p.connection_type = peer_info::web_seed; } void web_peer_connection::handle_padfile(buffer::const_interval& recv_buffer) { boost::shared_ptr t = associated_torrent().lock(); TORRENT_ASSERT(t); torrent_info const& info = t->torrent_file(); while (!m_file_requests.empty() && info.orig_files().pad_file_at(m_file_requests.front())) { // the next file is a pad file. We didn't actually send // a request for this since it most likely doesn't exist on // the web server anyway. Just pretend that we received a // bunch of zeroes here and pop it again int file_index = m_file_requests.front(); m_file_requests.pop_front(); size_type file_size = info.orig_files().file_size(file_index); peer_request front_request = m_requests.front(); TORRENT_ASSERT(m_block_pos < front_request.length); int pad_size = int((std::min)(file_size, size_type(front_request.length - m_block_pos))); // insert zeroes to represent the pad file m_piece.resize(m_piece.size() + size_t(pad_size), 0); m_block_pos += pad_size; incoming_piece_fragment(pad_size); if (maybe_harvest_block()) recv_buffer = receive_buffer(); if (associated_torrent().expired()) return; } } }