git.sesse.net Git - cubemap/blob - udpinput.cpp

   1 #include <assert.h>
   2 #include <errno.h>
   3 #include <fcntl.h>
   4 #include <poll.h>
   5 #include <stddef.h>
   6 #include <stdlib.h>
   7 #include <sys/socket.h>
   8 #include <time.h>
   9 #include <unistd.h>
  10 #include <math.h>
  11 #include <string>
  12
  13 #include "acceptor.h"
  14 #include "log.h"
  15 #include "serverpool.h"
  16 #include "state.pb.h"
  17 #include "stream.h"
  18 #include "udpinput.h"
  19 #include "util.h"
  20 #include "version.h"
  21
  22 using namespace std;
  23
  24 extern ServerPool *servers;
  25
  26 namespace {
  27
  28 // Similar to parse_hostport(), but only parses the IP address,
  29 // and does not use mapped-v4 addresses, since multicast seems
  30 // to not like that too much.
  31 bool parse_ip_address(const string &ip, sockaddr_storage *addr)
  32 {
  33         memset(addr, 0, sizeof(*addr));
  34
  35         assert(!ip.empty());
  36         if (ip[0] == '[') {
  37                 sockaddr_in6 *addr6 = (sockaddr_in6 *)addr;
  38                 addr6->sin6_family = AF_INET6;
  39                 if (ip[ip.size() - 1] != ']') {
  40                         log(ERROR, "address '%s' is malformed; must be either [ipv6addr] or ipv4addr",
  41                                 ip.c_str());
  42                         return false;
  43                 }
  44                 string raw_ip(ip.begin() + 1, ip.end() - 1);
  45                 if (inet_pton(AF_INET6, raw_ip.c_str(), &addr6->sin6_addr) != 1) {
  46                         log(ERROR, "'%s' is not a valid IPv6 address", raw_ip.c_str());
  47                         return false;
  48                 }
  49         } else {
  50                 sockaddr_in *addr4 = (sockaddr_in *)addr;
  51                 addr4->sin_family = AF_INET;
  52                 if (inet_pton(AF_INET, ip.c_str(), &addr4->sin_addr) != 1) {
  53                         log(ERROR, "'%s' is not a valid IPv4 address");
  54                         return false;
  55                 }
  56         }
  57
  58         return true;
  59 }
  60
  61 bool maybe_join_multicast_group(int sock, const string &group, const string &source)
  62 {
  63         if (group.empty()) {
  64                 // Not multicast.
  65                 return true;
  66         }
  67
  68         // Join the given multicast group (ASM or SSM).
  69         // TODO: Also support sources apart from multicast groups,
  70         // e.g. udp://[::1]:1234 for only receiving from localhost.
  71         if (!source.empty()) {
  72                 // Single-Source Multicast (SSM).
  73                 group_source_req gsr;
  74                 memset(&gsr, 0, sizeof(gsr));
  75                 if (!parse_ip_address(group, &gsr.gsr_group)) {
  76                         return false;
  77                 }
  78                 if (!parse_ip_address(source, &gsr.gsr_source)) {
  79                         return false;
  80                 }
  81                 int level = (gsr.gsr_group.ss_family == AF_INET) ? SOL_IP : SOL_IPV6;
  82                 if (setsockopt(sock, level, MCAST_JOIN_SOURCE_GROUP, &gsr, sizeof(gsr)) == -1) {
  83                         log_perror("setsockopt(MCAST_JOIN_SOURCE_GROUP)");
  84                         return false;
  85                 }
  86         } else {
  87                 // Any-Source Multicast (ASM).
  88                 group_req gr;
  89                 memset(&gr, 0, sizeof(gr));
  90                 if (!parse_ip_address(group, &gr.gr_group)) {
  91                         return false;
  92                 }
  93                 int level = (gr.gr_group.ss_family == AF_INET) ? SOL_IP : SOL_IPV6;
  94                 if (setsockopt(sock, level, MCAST_JOIN_GROUP, &gr, sizeof(gr)) == -1) {
  95                         log_perror("setsockopt(MCAST_JOIN_GROUP)");
  96                         return false;
  97                 }
  98         }
  99
 100         return true;
 101 }
 102
 103 }  // namespace
 104
 105 UDPInput::UDPInput(const string &url)
 106         : url(url),
 107           sock(-1)
 108 {
 109         // Should be verified by the caller.
 110         string protocol;
 111         bool ok = parse_url(url, &protocol, &user, &host, &port, &path);
 112         assert(ok);
 113
 114         construct_header();
 115
 116         stats.url = url;
 117         stats.connect_time = time(nullptr);
 118 }
 119
 120 UDPInput::UDPInput(const InputProto &serialized)
 121         : url(serialized.url()),
 122           sock(serialized.sock())
 123 {
 124         // Set back the close-on-exec flag for the socket.
 125         // (This can't leak into a child, since we haven't been started yet.)
 126         fcntl(sock, F_SETFD, O_CLOEXEC);
 127
 128         // Should be verified by the caller.
 129         string protocol;
 130         bool ok = parse_url(url, &protocol, &user, &host, &port, &path);
 131         assert(ok);
 132
 133         construct_header();
 134
 135         stats.url = url;
 136         stats.bytes_received = serialized.bytes_received();
 137         stats.data_bytes_received = serialized.data_bytes_received();
 138         if (serialized.has_connect_time()) {
 139                 stats.connect_time = serialized.connect_time();
 140         } else {
 141                 stats.connect_time = time(nullptr);
 142         }
 143 }
 144
 145 InputProto UDPInput::serialize() const
 146 {
 147         // Unset the close-on-exec flag for the socket.
 148         // (This can't leak into a child, since there's only one thread left.)
 149         fcntl(sock, F_SETFD, 0);
 150
 151         InputProto serialized;
 152         serialized.set_url(url);
 153         serialized.set_sock(sock);
 154         serialized.set_bytes_received(stats.bytes_received);
 155         serialized.set_data_bytes_received(stats.data_bytes_received);
 156         serialized.set_connect_time(stats.connect_time);
 157         serialized.set_is_metacube_encoded(false);
 158         return serialized;
 159 }
 160
 161 void UDPInput::close_socket()
 162 {
 163         safe_close(sock);
 164         sock = -1;
 165 }
 166
 167 void UDPInput::construct_header()
 168 {
 169         http_header =
 170                 "HTTP/1.0 200 OK\r\n"
 171                 "Content-type: application/octet-stream\r\n"
 172                 "Cache-control: no-cache\r\n"
 173                 "Server: " SERVER_IDENTIFICATION "\r\n"
 174                 "Connection: close\r\n";
 175 }
 176
 177 void UDPInput::add_destination(int stream_index)
 178 {
 179         stream_indices.push_back(stream_index);
 180         servers->set_header(stream_index, http_header, "");
 181 }
 182
 183 void UDPInput::do_work()
 184 {
 185         while (!should_stop()) {
 186                 if (sock == -1) {
 187                         int port_num = atoi(port.c_str());
 188                         sockaddr_in6 addr = create_any_address(port_num);
 189                         sock = create_server_socket(addr, UDP_SOCKET);
 190                         if (sock == -1) {
 191                                 log(WARNING, "[%s] UDP socket creation failed. Waiting 0.2 seconds and trying again...",
 192                                              url.c_str());
 193                                 usleep(200000);
 194                                 continue;
 195                         }
 196
 197                         // The syntax udp://source@group (abusing the username field
 198                         // to store the sender in SSM) seems to be a VLC invention.
 199                         // We mimic it.
 200                         if (!maybe_join_multicast_group(sock, host, user)) {
 201                                 log(WARNING, "[%s] Multicast join failed. Waiting 0.2 seconds and trying again...",
 202                                              url.c_str());
 203                                 safe_close(sock);
 204                                 sock = -1;
 205                                 usleep(200000);
 206                                 continue;
 207                         }
 208                 }
 209
 210                 // Wait for a packet, or a wakeup.
 211                 bool activity = wait_for_activity(sock, POLLIN, nullptr);
 212                 if (!activity) {
 213                         // Most likely, should_stop was set.
 214                         continue;
 215                 }
 216
 217                 int ret;
 218                 do {
 219                         ret = recv(sock, packet_buf, sizeof(packet_buf), 0);
 220                 } while (ret == -1 && errno == EINTR);
 221
 222                 if (ret < 0) {  // Note that zero-byte packets are legal.
 223                         log_perror("recv");
 224                         close_socket();
 225                         continue;
 226                 }
 227
 228                 {
 229                         lock_guard<mutex> lock(stats_mutex);
 230                         stats.bytes_received += ret;
 231                         stats.data_bytes_received += ret;
 232                 }
 233
 234                 for (size_t stream_index : stream_indices) {
 235                         servers->add_data(stream_index, packet_buf, ret, /*metacube_flags=*/0, /*pts=*/RationalPTS());
 236                 }
 237         }
 238 }
 239
 240 InputStats UDPInput::get_stats() const
 241 {
 242         lock_guard<mutex> lock(stats_mutex);
 243         return stats;
 244 }