udp_recv.c

   1 /*
   2  * Copyright (C) 2005-2009 Andre Noll <maan@systemlinux.org>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6 /** \file udp_recv.c Paraslash's udp receiver */
   7
   8 #include <regex.h>
   9 #include <dirent.h>
  10 #include <sys/socket.h>
  11 #include <net/if.h>
  12
  13 #include "para.h"
  14 #include "error.h"
  15 #include "portable_io.h"
  16 #include "list.h"
  17 #include "sched.h"
  18 #include "ggo.h"
  19 #include "recv.h"
  20 #include "udp_recv.cmdline.h"
  21 #include "string.h"
  22 #include "net.h"
  23 #include "fd.h"
  24 #include "buffer_tree.h"
  25
  26 /**
  27  * Data specific to the udp receiver.
  28  *
  29  * \sa \ref receiver, \ref receiver_node.
  30  */
  31 struct private_udp_recv_data {
  32         /** The socket file descriptor. */
  33         int fd;
  34         struct btr_pool *btrp;
  35         struct timeval last_read_time;
  36 };
  37
  38 static void udp_recv_pre_select(struct sched *s, struct task *t)
  39 {
  40         struct receiver_node *rn = container_of(t, struct receiver_node, task);
  41         struct private_udp_recv_data *purd = rn->private_data;
  42
  43         if (generic_recv_pre_select(s, t) <= 0)
  44                 return;
  45         para_fd_set(purd->fd, &s->rfds, &s->max_fileno);
  46 }
  47
  48 static int udp_check_eof(size_t sz, struct iovec iov[2])
  49 {
  50         if (sz < FEC_EOF_PACKET_LEN)
  51                 return 0;
  52         if (iov[0].iov_len >= FEC_EOF_PACKET_LEN) {
  53                 if (memcmp(iov[0].iov_base, FEC_EOF_PACKET,
  54                                 FEC_EOF_PACKET_LEN) != 0)
  55                         return 0;
  56                 return -E_RECV_EOF;
  57         }
  58         if (memcmp(iov[0].iov_base, FEC_EOF_PACKET, iov[0].iov_len) != 0)
  59                 return 0;
  60         if (memcmp(iov[1].iov_base, FEC_EOF_PACKET + iov[0].iov_len,
  61                         FEC_EOF_PACKET_LEN - iov[0].iov_len) != 0)
  62                 return 0;
  63         return -E_RECV_EOF;
  64 }
  65
  66 static void udp_recv_post_select(__a_unused struct sched *s, struct task *t)
  67 {
  68         struct receiver_node *rn = container_of(t, struct receiver_node, task);
  69         struct private_udp_recv_data *purd = rn->private_data;
  70         struct btr_node *btrn = rn->btrn;
  71         size_t packet_size;
  72         struct iovec iov[2];
  73         int ret, iovcnt;
  74
  75         t->error = 0;
  76         ret = btr_node_status(btrn, 0, BTR_NT_ROOT);
  77         if (ret < 0)
  78                 goto err;
  79         if (ret == 0)
  80                 return;
  81         if (!FD_ISSET(purd->fd, &s->rfds)) {
  82                 struct timeval tmp;
  83                 tv_add(&purd->last_read_time, &(struct timeval)EMBRACE(5, 0),
  84                         &tmp);
  85                 ret = -E_UDP_TIMEOUT;
  86                 if (tv_diff(now, &tmp, NULL) > 0)
  87                         goto err;
  88                 return;
  89         }
  90         iovcnt = btr_pool_get_buffers(purd->btrp, iov);
  91         ret = -E_UDP_OVERRUN;
  92         if (iovcnt == 0)
  93                 goto err;
  94         ret = para_readv(purd->fd, iov, iovcnt);
  95         if (ret == 0)
  96                 ret = -E_RECV_EOF;
  97         if (ret < 0)
  98                 goto err;
  99         packet_size = ret;
 100         ret = udp_check_eof(packet_size, iov);
 101         if (ret < 0)
 102                 goto err;
 103         purd->last_read_time = *now;
 104         if (iov[0].iov_len >= packet_size)
 105                 btr_add_output_pool(purd->btrp, packet_size, btrn);
 106         else { /* both buffers contain data */
 107                 btr_add_output_pool(purd->btrp, iov[0].iov_len, btrn);
 108                 btr_add_output_pool(purd->btrp, packet_size - iov[0].iov_len,
 109                         btrn);
 110         }
 111         return;
 112 err:
 113         btr_remove_node(btrn);
 114         t->error = ret;
 115         close(purd->fd);
 116         purd->fd = -1;
 117 }
 118
 119 static void udp_recv_close(struct receiver_node *rn)
 120 {
 121         struct private_udp_recv_data *purd = rn->private_data;
 122
 123         if (purd->fd >= 0)
 124                 close(purd->fd);
 125         btr_pool_free(purd->btrp);
 126         free(rn->private_data);
 127 }
 128
 129 static void *udp_recv_parse_config(int argc, char **argv)
 130 {
 131         int ret;
 132         struct udp_recv_args_info *tmp =
 133                 para_calloc(sizeof(struct udp_recv_args_info));
 134
 135         ret = udp_recv_cmdline_parser(argc, argv, tmp)? -E_UDP_SYNTAX : 1;
 136         if (ret >= 0)
 137                 return tmp;
 138         free(tmp);
 139         return NULL;
 140 }
 141
 142 /*
 143  * Perform AF-independent joining of multicast receive addresses.
 144  *
 145  * \param fd    Bound socket descriptor.
 146  * \param iface The receiving multicast interface, or NULL for the default.
 147  *
 148  * \return Zero if okay, negative on error.
 149  */
 150 static int mcast_receiver_setup(int fd, const char *iface)
 151 {
 152         struct sockaddr_storage ss;
 153         socklen_t sslen = sizeof(ss);
 154         int id = iface == NULL ? 0 : if_nametoindex(iface);
 155
 156         if (getsockname(fd, (struct sockaddr *)&ss, &sslen) < 0)
 157                 goto err;
 158
 159         if (iface != NULL && id == 0)
 160                 PARA_WARNING_LOG("could not resolve interface %s, using default", iface);
 161
 162         switch (ss.ss_family) {
 163         case AF_INET:
 164                 if (IN_MULTICAST(htonl(((struct sockaddr_in *)&ss)->sin_addr.s_addr))) {
 165 #ifdef HAVE_IP_MREQN
 166                         struct ip_mreqn m4;
 167
 168                         m4.imr_address.s_addr   = INADDR_ANY;
 169                         m4.imr_ifindex          = id;
 170 #else
 171                         struct ip_mreq m4;
 172
 173                         m4.imr_interface.s_addr = INADDR_ANY;
 174                         if (id != 0)
 175                                 PARA_ERROR_LOG("Setting IPv4 receiver mcast interface not supported.");
 176
 177 #endif
 178                         m4.imr_multiaddr        = ((struct sockaddr_in *)&ss)->sin_addr;
 179
 180                         if (setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &m4, sizeof(m4)) < 0)
 181                                 break;
 182                 }
 183                 return 0;
 184         case AF_INET6:
 185                 if (IN6_IS_ADDR_MULTICAST(&((struct sockaddr_in6 *)&ss)->sin6_addr)) {
 186                         struct ipv6_mreq m6;
 187
 188                         memset(&m6, 0, sizeof(m6));
 189                         memcpy(&m6.ipv6mr_multiaddr, &((struct sockaddr_in6 *)&ss)->sin6_addr, 16);
 190                         m6.ipv6mr_interface = id;
 191                         if (setsockopt(fd, IPPROTO_IPV6, IPV6_JOIN_GROUP, &m6, sizeof(m6)) < 0)
 192                                 break;
 193                 }
 194                 return 0;
 195         default:
 196                 PARA_ERROR_LOG("address family %d not supported", ss.ss_family);
 197                 return -E_ADDRESS_LOOKUP;
 198         }
 199 err:
 200         return -ERRNO_TO_PARA_ERROR(errno);
 201 }
 202
 203 static int udp_recv_open(struct receiver_node *rn)
 204 {
 205         struct private_udp_recv_data *purd;
 206         struct udp_recv_args_info *c = rn->conf;
 207         char  *iface = c->iface_given ? c->iface_arg : NULL;
 208         int ret;
 209
 210         rn->private_data = para_calloc(sizeof(struct private_udp_recv_data));
 211         purd = rn->private_data;
 212
 213         ret = makesock(IPPROTO_UDP, 1, c->host_arg, c->port_arg, NULL);
 214         if (ret < 0)
 215                 goto err;
 216         purd->fd = ret;
 217
 218         ret = mcast_receiver_setup(purd->fd, iface);
 219         if (ret < 0) {
 220                 close(purd->fd);
 221                 goto err;
 222         }
 223
 224         ret = mark_fd_nonblocking(purd->fd);
 225         if (ret < 0) {
 226                 close(purd->fd);
 227                 goto err;
 228         }
 229         PARA_INFO_LOG("receiving from %s:%d, fd=%d\n", c->host_arg,
 230                 c->port_arg, purd->fd);
 231         purd->btrp = btr_pool_new("udp_recv", 320 * 1024);
 232         purd->last_read_time = *now;
 233         return purd->fd;
 234 err:
 235         free(rn->private_data);
 236         return ret;
 237 }
 238
 239 static void udp_recv_free_config(void *conf)
 240 {
 241         udp_recv_cmdline_parser_free(conf);
 242         free(conf);
 243 }
 244
 245 /**
 246  * The init function of the udp receiver.
 247  *
 248  * \param r Pointer to the receiver struct to initialize.
 249  *
 250  * Initialize all function pointers of \a r.
 251  */
 252 void udp_recv_init(struct receiver *r)
 253 {
 254         struct udp_recv_args_info dummy;
 255
 256         udp_recv_cmdline_parser_init(&dummy);
 257         r->open = udp_recv_open;
 258         r->close = udp_recv_close;
 259         r->pre_select = udp_recv_pre_select;
 260         r->post_select = udp_recv_post_select;
 261         r->parse_config = udp_recv_parse_config;
 262         r->free_config = udp_recv_free_config;
 263         r->help = (struct ggo_help) {
 264                 .short_help = udp_recv_args_info_help,
 265                 .detailed_help = udp_recv_args_info_detailed_help
 266         };
 267         udp_recv_cmdline_parser_free(&dummy);
 268 }