diff options
Diffstat (limited to 'src/plugins/youtube')
| -rw-r--r-- | src/plugins/youtube/YoutubeMediaProxy.cpp | 733 |
1 files changed, 733 insertions, 0 deletions
diff --git a/src/plugins/youtube/YoutubeMediaProxy.cpp b/src/plugins/youtube/YoutubeMediaProxy.cpp new file mode 100644 index 0000000..e8d0383 --- /dev/null +++ b/src/plugins/youtube/YoutubeMediaProxy.cpp @@ -0,0 +1,733 @@ +#include "../../../plugins/youtube/YoutubeMediaProxy.hpp" +#include "../../../include/NetUtils.hpp" + +#include <vector> +#include <stdio.h> +#include <string.h> +#include <errno.h> +#include <signal.h> +#include <assert.h> + +#include <unistd.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <fcntl.h> + +// TODO: What if the client sends a new header without reconnecting? is that even allowed by http standard? +// TODO: Detect when download has finished (and close connection). + +namespace QuickMedia { + static const int MAX_BUFFER_SIZE = 65536; + static const int RANGE = 524287; + static const char download_error_response_msg[] = + "HTTP/1.1 500 Internal Server Error\r\n" + "Content-Length: 0\r\n\r\n"; + + static bool set_non_blocking(int fd) { + const int flags = fcntl(fd, F_GETFL, 0); + if(fd == -1 || fcntl(fd, F_SETFL, flags | O_NONBLOCK) == -1) + return false; + return true; + } + + // TODO: Restrict range end to remote file size (content-length which we have saved). + // TODO: Check if custom youtube redirect code is needed + bool YoutubeMediaProxy::start_download(const std::string &media_url, ReadProgram &read_program, int range_start, bool include_header, bool is_livestream, int livestream_sequence) { + std::string r = std::to_string(range_start) + "-" + std::to_string(range_start + RANGE); + + std::string url = media_url + "&rn=" + std::to_string(rn) + "&rbuf=" + std::to_string(rbuf); + std::vector<const char*> args = { "curl", + //"-H", "Accept-Language: en-US,en;q=0.5", "-H", "Connection: keep-alive", + //"-H", "user-agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.138 Safari/537.36", + "-g", "-s", "-L", "-f" }; + + if(is_livestream) { + if(livestream_sequence != -1) + url += "&sq=" + std::to_string(livestream_sequence); + } else { + args.insert(args.end(), { "-r", r.c_str() }); + } + + if(include_header) + args.push_back("-i"); + + //fprintf(stderr, "url: %s\n", url.c_str()); + + args.insert(args.end(), { "--", url.c_str(), nullptr }); + + if(exec_program_pipe(args.data(), &read_program) != 0) + return false; + + if(!set_non_blocking(read_program.read_fd)) { + perror("start_download: failed to set curl pipe non blocking mode"); + close(read_program.read_fd); + kill(read_program.pid, SIGTERM); + read_program.read_fd = -1; + read_program.pid = -1; + return false; + } + + ++rn; + rbuf += 3000; + if(rbuf > 75000) rbuf = 75000; + return true; + } + + YoutubeStaticMediaProxy::~YoutubeStaticMediaProxy() { + stop(); + } + + bool YoutubeStaticMediaProxy::start(const std::string &youtube_media_url, int content_length) { + if(socket_fd != -1) + return false; + + socket_fd = socket(AF_INET, SOCK_STREAM, 0); + if(socket_fd == -1) { + perror("YoutubeStaticMediaProxy::start: socket failed"); + return false; + } + + socklen_t response_sock_addr_len; + struct sockaddr_in server_addr; + memset(&server_addr, 0, sizeof(server_addr)); + server_addr.sin_family = AF_INET; + server_addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK); + server_addr.sin_port = htons(0); + + if(bind(socket_fd, (struct sockaddr*)&server_addr, sizeof(server_addr)) == -1) { + perror("YoutubeStaticMediaProxy::start: bind failed"); + goto err; + } + + if(listen(socket_fd, 2) == -1) { + perror("YoutubeStaticMediaProxy::start: listen failed"); + goto err; + } + + if(!set_non_blocking(socket_fd)) { + perror("YoutubeStaticMediaProxy::start: failed to set socket non blocking mode"); + goto err; + } + + struct sockaddr_in response_sock_addr; + response_sock_addr_len = sizeof(response_sock_addr); + if(getsockname(socket_fd, (struct sockaddr*)&response_sock_addr, &response_sock_addr_len) == -1) { + perror("YoutubeStaticMediaProxy::start: getsockname failed"); + goto err; + } + + port = ntohs(response_sock_addr.sin_port); + this->youtube_media_url = youtube_media_url; + this->content_length = content_length; + return true; + + err: + if(downloader_read_program.read_fd != -1) + close(downloader_read_program.read_fd); + if(downloader_read_program.pid != -1) + kill(downloader_read_program.pid, SIGTERM); + close(socket_fd); + socket_fd = -1; + return false; + } + + void YoutubeStaticMediaProxy::stop() { + if(downloader_read_program.read_fd != -1) { + close(downloader_read_program.read_fd); + downloader_read_program.read_fd = -1; + } + + if(downloader_read_program.pid != -1) { + kill(downloader_read_program.pid, SIGTERM); + wait_program(downloader_read_program.pid); + downloader_read_program.pid = -1; + } + + if(client_fd != -1) { + close(client_fd); + client_fd = -1; + } + + if(socket_fd != -1) { + close(socket_fd); + socket_fd = -1; + } + + clear_download_state(); + client_request_buffer.clear(); + client_request_finished = false; + } + + YoutubeStaticMediaProxy::Error YoutubeStaticMediaProxy::update() { + if(socket_fd == -1) + return Error::OK; + + if(client_fd == -1) { + client_fd = accept_client(); + if(client_fd == -1) + return Error::OK; + } else { + const int new_client_fd = accept_client(); + if(new_client_fd != -1) { + on_client_disconnect(); + client_fd = new_client_fd; + } + } + + Error err = read_client_data(); + if(err != Error::OK || !client_request_finished) + return err; + if(downloader_read_program.pid == -1) + return Error::ERROR; + return handle_download(); + } + + bool YoutubeStaticMediaProxy::get_address(std::string &address) { + if(socket_fd == -1) + return false; + + address = "http://127.0.0.1:" + std::to_string(port); + return true; + } + + void YoutubeStaticMediaProxy::on_client_disconnect() { + client_request_buffer.clear(); + client_request_finished = false; + + if(client_fd != -1) { + close(client_fd); + client_fd = -1; + } + + if(downloader_read_program.pid != -1) + kill(downloader_read_program.pid, SIGTERM); + + update_download_program_status(true); + } + + // Returns 0 if start range is not found + static int header_extract_start_range(const std::string &header) { + std::string range = header_extract_value(header, "range"); + if(range.empty()) + return 0; + + int start_range = 0; + if(sscanf(range.c_str(), " bytes=%d", &start_range) != 1) + return 0; + + return start_range; + } + + // TODO: What about hls (live streams)? need to test with that. There may not be a need to use YoutubeMediaProxy for that case (in that case document it). + YoutubeStaticMediaProxy::Error YoutubeStaticMediaProxy::read_client_data() { + if(client_request_finished) + return Error::OK; + + char read_buffer[4096]; + const ssize_t num_bytes_read = read(client_fd, read_buffer, sizeof(read_buffer)); + if(num_bytes_read == -1) { + const int err = errno; + if(err == EAGAIN || err == EWOULDBLOCK) { + return Error::OK; + } else if(err == EPIPE || err == ECONNRESET) { + //fprintf(stderr, "YoutubeStaticMediaProxy::read_client_data: client disconnected\n"); + on_client_disconnect(); + return Error::ERROR; + } else { + perror("YoutubeStaticMediaProxy::read_client_data: read failed"); + return Error::ERROR; + } + } else if(num_bytes_read == 0) { + //fprintf(stderr, "YoutubeStaticMediaProxy::read_client_data: client disconnected\n"); + on_client_disconnect(); + return Error::ERROR; + } + + client_request_buffer.append(read_buffer, num_bytes_read); + const size_t header_end = client_request_buffer.find("\r\n\r\n"); + if(header_end != std::string::npos) { + client_request_buffer.erase(header_end + 4); + client_request_finished = true; + + int new_start_range = header_extract_start_range(client_request_buffer); + //fprintf(stderr, "got new range from client: %d\n", new_start_range); + if(new_start_range >= 0) { + if(downloader_read_program.pid != -1) { + kill(downloader_read_program.pid, SIGTERM); + wait_program(downloader_read_program.pid); + downloader_read_program.pid = -1; + } + clear_download_state(); + update_download_program_status(false, new_start_range, true); + } + } else { + if(client_request_buffer.size() > MAX_BUFFER_SIZE) { + client_request_finished = true; + fprintf(stderr, "YoutubeStaticMediaProxy::read_client_data: buffer is full (malicious client?)\n"); + return Error::ERROR; + } + } + return Error::OK; + } + + void YoutubeStaticMediaProxy::clear_download_state() { + download_header.clear(); + download_header_finished = false; + download_header_sent = false; + download_header_remaining_sent = false; + download_header_written_offset = 0; + } + + YoutubeStaticMediaProxy::Error YoutubeStaticMediaProxy::update_download_program_status(bool client_disconnected, int new_range_start, bool restart_download) { + int program_status = 0; + if(downloader_read_program.pid != -1) { + if(client_disconnected) { + wait_program(downloader_read_program.pid); + } else { + if(!wait_program_non_blocking(downloader_read_program.pid, &program_status)) + return Error::OK; + } + downloader_read_program.pid = -1; + } + + if(downloader_read_program.read_fd != -1) { + close(downloader_read_program.read_fd); + downloader_read_program.read_fd = -1; + } + + // TODO: Why is this not 0 when download finishes? + if(program_status != 0) { + //fprintf(stderr, "YoutubeStaticMediaProxy::update_download_program_status: download failed, exit status: %d\n", program_status); + if(client_fd != -1) { + write(client_fd, download_error_response_msg, sizeof(download_error_response_msg) - 1); + close(client_fd); + client_fd = -1; + client_request_buffer.clear(); + client_request_finished = false; + } + return Error::ERROR; + } + + if(client_disconnected) { + current_download_range = 0; + } else { + current_download_range += RANGE + 1; + } + + if(new_range_start != -1) { + download_range_start = new_range_start; + current_download_range = download_range_start; + } + + if(new_range_start == -1) { + download_header_finished = true; + download_header_sent = true; + download_header_remaining_sent = true; + } else { + clear_download_state(); + } + + if(client_disconnected) { + clear_download_state(); + return Error::ERROR; + } + + if(!restart_download) + return Error::OK; + + const bool start_download_success = start_download(youtube_media_url, downloader_read_program, current_download_range, new_range_start != -1); + if(!start_download_success) { + fprintf(stderr, "YoutubeStaticMediaProxy::update_download_program_status: failed to start download\n"); + if(client_fd != -1) { + write(client_fd, download_error_response_msg, sizeof(download_error_response_msg) - 1); + close(client_fd); + client_fd = -1; + client_request_buffer.clear(); + client_request_finished = false; + } + + clear_download_state(); + return Error::ERROR; + } + + return Error::OK; + } + + static void header_replace_content_length(std::string &header, size_t header_size, int new_content_length) { + if(new_content_length < 0) + new_content_length = 0; + + const char *content_length_p = strcasestr(header.c_str(), "content-length:"); + if(!content_length_p) + return; + + const size_t content_length_start = (content_length_p + 15) - header.c_str(); + if(content_length_start >= header_size) + return; + const size_t line_end = header.find("\r\n", content_length_start); + header.replace(content_length_start, line_end - content_length_start, std::to_string(new_content_length)); + } + + YoutubeStaticMediaProxy::Error YoutubeStaticMediaProxy::continue_send(const char *buffer_start, size_t total_bytes_to_write, int &buffer_offset) { + int num_bytes_to_write = total_bytes_to_write - buffer_offset; + //assert(num_bytes_to_write >= 0); + if(num_bytes_to_write < 0) num_bytes_to_write = 0; + if(num_bytes_to_write == 0) { + buffer_offset = 0; + return Error::OK; + } + + const ssize_t num_bytes_written = write(client_fd, buffer_start + buffer_offset, num_bytes_to_write); + if(num_bytes_written == -1) { + const int err = errno; + if(err == EAGAIN || err == EWOULDBLOCK) { + return Error::OK; + } else if(err == EPIPE || err == ECONNRESET) { + //fprintf(stderr, "YoutubeStaticMediaProxy::continue_send: client disconnected\n"); + on_client_disconnect(); + return Error::ERROR; + } else { + perror("YoutubeStaticMediaProxy::continue_send: write failed"); + return Error::ERROR; + } + } else if(num_bytes_written == 0) { + //fprintf(stderr, "YoutubeStaticMediaProxy::continue_send: client disconnected\n"); + on_client_disconnect(); + return Error::ERROR; + } else if(num_bytes_written != num_bytes_to_write) { + buffer_offset += num_bytes_written; + } else { + buffer_offset = 0; + } + return Error::OK; + } + + static bool http_is_redirect(const char *header, size_t size) { + const void *end_of_first_line_p = memmem(header, size, "\r\n", 2); + if(!end_of_first_line_p) + return false; + return memmem(header, (const char*)end_of_first_line_p - header, " 30", 3) != nullptr; + } + + static size_t find_start_of_first_non_redirect_header(const char *headers, size_t size, size_t &header_end) { + const char *start = headers; + while(size > 0) { + const void *end_of_header = memmem(headers, size, "\r\n\r\n", 4); + if(!end_of_header) + return std::string::npos; + + const size_t offset_to_end_of_headers = ((const char*)end_of_header + 4) - headers; + if(!http_is_redirect(headers, offset_to_end_of_headers)) { + header_end = (headers - start) + offset_to_end_of_headers; + return headers - start; + } + + headers += offset_to_end_of_headers; + size -= offset_to_end_of_headers; + } + return std::string::npos; + } + + YoutubeStaticMediaProxy::Error YoutubeStaticMediaProxy::handle_download() { + // TODO: Maybe read even if write is being slow and failing? + if(download_read_buffer_offset == 0) { + downloader_num_read_bytes = read(downloader_read_program.read_fd, download_read_buffer, sizeof(download_read_buffer)); + if(downloader_num_read_bytes == -1) { + const int err = errno; + if(err == EAGAIN || err == EWOULDBLOCK) { + return Error::OK; + } else { + perror("YoutubeStaticMediaProxy::handle_download: curl read failed"); + return Error::ERROR; + } + } else if(downloader_num_read_bytes == 0) { + Error err = update_download_program_status(false, -1, true); + if(err != Error::OK) + return err; + } + } + + if(!download_header_finished) { + download_header.append(download_read_buffer, downloader_num_read_bytes); + size_t header_end = std::string::npos; + const size_t offset_to_start_of_header = find_start_of_first_non_redirect_header(download_header.c_str(), download_header.size(), header_end); + if(header_end != std::string::npos) { + download_header.erase(0, offset_to_start_of_header); + header_end -= offset_to_start_of_header; + + download_header_finished = true; + download_header_sent = false; + download_header_remaining_sent = false; + download_header_written_offset = 0; + download_header_offset_to_end_of_header = header_end; + download_read_buffer_offset = -1; + + header_replace_content_length(download_header, header_end, content_length - download_range_start); + } else { + if(download_header.size() > MAX_BUFFER_SIZE) { + fprintf(stderr, "YoutubeStaticMediaProxy::handle_download: buffer is full (malicious server?)\n"); + if(downloader_read_program.pid != -1) { + kill(downloader_read_program.pid, SIGTERM); + wait_program(downloader_read_program.pid); + downloader_read_program.pid = -1; + } + clear_download_state(); + update_download_program_status(false, 0, false); + return Error::ERROR; + } + } + } + + if(download_header_finished && !download_header_sent) { + Error err = continue_send(download_header.data(), download_header_offset_to_end_of_header, download_header_written_offset); + if(err != Error::OK) + return err; + + if(download_header_written_offset == 0) { + download_header_sent = true; + download_header_written_offset = download_header_offset_to_end_of_header; + } + } + + if(download_header_finished && !download_header_remaining_sent) { + Error err = continue_send(download_header.data(), download_header.size(), download_header_written_offset); + if(err != Error::OK) + return err; + + if(download_header_written_offset == 0) { + download_header_remaining_sent = true; + download_read_buffer_offset = 0; + return Error::OK; + } + } + + if(download_header_remaining_sent) + return continue_send(download_read_buffer, downloader_num_read_bytes, download_read_buffer_offset); + + return Error::OK; + } + + int YoutubeStaticMediaProxy::accept_client() { + struct sockaddr_in client_addr; + socklen_t client_addr_len = sizeof(client_addr); + int new_client_fd = accept(socket_fd, (struct sockaddr*)&client_addr, &client_addr_len); + if(new_client_fd == -1) { + const int err = errno; + if(err == EAGAIN || err == EWOULDBLOCK) { + return -1; + } else { + perror("YoutubeStaticMediaProxy::accept_client accept failed"); + return -1; + } + } + + if(!set_non_blocking(new_client_fd)) { + perror("YoutubeStaticMediaProxy::accept_client: failed to set client socket non blocking mode"); + close(new_client_fd); + return -1; + } + + //fprintf(stderr, "YoutubeStaticMediaProxy::accept_client: client connected!\n"); + return new_client_fd; + } + + YoutubeLiveStreamMediaProxy::~YoutubeLiveStreamMediaProxy() { + stop(); + } + + bool YoutubeLiveStreamMediaProxy::start(const std::string &youtube_media_url, int) { + fd[0] = -1; + fd[1] = -1; + if(pipe(fd) == -1) { + perror("YoutubeLiveStreamMediaProxy::start: failed to open pipe"); + return false; + } + + //if(socketpair(AF_UNIX, SOCK_STREAM, 0, fd) == -1) { + // perror("YoutubeLiveStreamMediaProxy::start: failed to open pipe"); + // return false; + //} + + for(int i = 0; i < 2; ++i) { + if(!set_non_blocking(fd[i])) { + stop(); + return false; + } + } + + if(!start_download(youtube_media_url, downloader_read_program, 0, true, true)) { + stop(); + return false; + } + + this->youtube_media_url = youtube_media_url; + return true; + } + + void YoutubeLiveStreamMediaProxy::stop() { + for(int i = 0; i < 2; ++i) { + if(fd[i] != -1) { + close(fd[i]); + fd[i] = -1; + } + } + + if(downloader_read_program.read_fd != -1) { + close(downloader_read_program.read_fd); + downloader_read_program.read_fd = -1; + } + + if(downloader_read_program.pid != -1) { + kill(downloader_read_program.pid, SIGTERM); + wait_program(downloader_read_program.pid); + downloader_read_program.pid = -1; + } + } + + YoutubeMediaProxy::Error YoutubeLiveStreamMediaProxy::update_download_program_status() { + int program_status = 0; + if(!wait_program_non_blocking(downloader_read_program.pid, &program_status)) + return Error::OK; + + downloader_read_program.pid = -1; + if(downloader_read_program.read_fd != -1) { + close(downloader_read_program.read_fd); + downloader_read_program.read_fd = -1; + } + + // TODO: Why is this not 0 when download finishes? + if(program_status != 0) { + //fprintf(stderr, "YoutubeLiveStreamMediaProxy::update_download_program_status: download failed, exit status: %d\n", program_status); + stop(); + return Error::ERROR; + } + + ++livestream_sequence_num; + const bool start_download_success = start_download(youtube_media_url, downloader_read_program, 0, false, true, livestream_sequence_num); + if(!start_download_success) { + fprintf(stderr, "YoutubeLiveStreamMediaProxy::update_download_program_status: failed to start download\n"); + stop(); + return Error::ERROR; + } + + return Error::OK; + } + + YoutubeMediaProxy::Error YoutubeLiveStreamMediaProxy::continue_send(const char *buffer_start, size_t total_bytes_to_write, int &buffer_offset) { + int num_bytes_to_write = total_bytes_to_write - buffer_offset; + //assert(num_bytes_to_write >= 0); + if(num_bytes_to_write < 0) num_bytes_to_write = 0; + if(num_bytes_to_write == 0) { + buffer_offset = 0; + return Error::OK; + } + + const ssize_t num_bytes_written = write(fd[1], buffer_start + buffer_offset, num_bytes_to_write); + if(num_bytes_written == -1) { + const int err = errno; + if(err == EAGAIN || err == EWOULDBLOCK) { + return Error::OK; + } else if(err == EPIPE || err == ECONNRESET) { + //fprintf(stderr, "YoutubeLiveStreamMediaProxy::continue_send: client disconnected\n"); + stop(); + return Error::ERROR; + } else { + perror("YoutubeLiveStreamMediaProxy::continue_send: write failed"); + return Error::ERROR; + } + } else if(num_bytes_written == 0) { + //fprintf(stderr, "YoutubeLiveStreamMediaProxy::continue_send: client disconnected\n"); + stop(); + return Error::ERROR; + } else if(num_bytes_written != num_bytes_to_write) { + buffer_offset += num_bytes_written; + } else { + buffer_offset = 0; + } + return Error::OK; + } + + YoutubeMediaProxy::Error YoutubeLiveStreamMediaProxy::update() { + if(fd[1] == -1 || downloader_read_program.read_fd == -1) + return Error::OK; + + if(download_read_buffer_offset == 0) { + downloader_num_read_bytes = read(downloader_read_program.read_fd, download_read_buffer, sizeof(download_read_buffer)); + if(downloader_num_read_bytes == -1) { + const int err = errno; + if(err == EAGAIN || err == EWOULDBLOCK) { + return Error::OK; + } else { + perror("YoutubeLiveStreamMediaProxy::update: curl read failed"); + return Error::ERROR; + } + } else if(downloader_num_read_bytes == 0) { + Error err = update_download_program_status(); + if(err != Error::OK) + return err; + } + } + + if(!download_header_finished) { + download_header.append(download_read_buffer, downloader_num_read_bytes); + size_t header_end = std::string::npos; + const size_t offset_to_start_of_header = find_start_of_first_non_redirect_header(download_header.c_str(), download_header.size(), header_end); + if(header_end != std::string::npos) { + download_header.erase(0, offset_to_start_of_header); + header_end -= offset_to_start_of_header; + + download_header_finished = true; + download_header_remaining_sent = false; + download_header_written_offset = header_end; + download_read_buffer_offset = -1; + fprintf(stderr, "header: |%.*s|\n", download_header_written_offset, download_header.c_str()); + + if(livestream_sequence_num == -1) { + // TODO: What about |header_end|? + std::string sequence_num = header_extract_value(download_header, "x-sequence-num"); + fprintf(stderr, "server sequence num: |%s|\n", sequence_num.c_str()); + if(sequence_num.empty()) + fprintf(stderr, "YoutubeLiveStreamMediaProxy::handle_download: missing sequence num from server\n"); + else + livestream_sequence_num = strtol(sequence_num.c_str(), nullptr, 10); + } + } else { + if(download_header.size() > MAX_BUFFER_SIZE) { + fprintf(stderr, "YoutubeLiveStreamMediaProxy::handle_download: buffer is full (malicious server?)\n"); + if(downloader_read_program.pid != -1) { + kill(downloader_read_program.pid, SIGTERM); + wait_program(downloader_read_program.pid); + downloader_read_program.pid = -1; + } + download_header_finished = true; + return Error::ERROR; + } + } + } + + if(download_header_finished && !download_header_remaining_sent) { + Error err = continue_send(download_header.data(), download_header.size(), download_header_written_offset); + if(err != Error::OK) + return err; + + if(download_header_written_offset == 0) { + download_header_remaining_sent = true; + download_read_buffer_offset = 0; + return Error::OK; + } + } + + if(download_header_remaining_sent) + return continue_send(download_read_buffer, downloader_num_read_bytes, download_read_buffer_offset); + + return Error::OK; + } + + bool YoutubeLiveStreamMediaProxy::get_address(std::string &address) { + if(fd[0] == -1) + return false; + + address = "fd://" + std::to_string(fd[0]); + return true; + } +}
\ No newline at end of file |