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 };
  36
  37 static void udp_recv_pre_select(struct sched *s, struct task *t)
  38 {
  39         struct receiver_node *rn = container_of(t, struct receiver_node, task);
  40         struct private_udp_recv_data *purd = rn->private_data;
  41
  42         if (generic_recv_pre_select(s, t) <= 0)
  43                 return;
  44         para_fd_set(purd->fd, &s->rfds, &s->max_fileno);
  45 }
  46
  47 static void udp_recv_post_select(__a_unused struct sched *s, struct task *t)
  48 {
  49         struct receiver_node *rn = container_of(t, struct receiver_node, task);
  50         struct private_udp_recv_data *purd = rn->private_data;
  51         struct btr_node *btrn = rn->btrn;
  52         int ret;
  53         char *buf = NULL;
  54         size_t packet_size, bufsize;
  55
  56         t->error = 0;
  57         ret = btr_node_status(btrn, 0, BTR_NT_ROOT);
  58         if (ret < 0)
  59                 goto err;
  60         if (ret == 0)
  61                 return;
  62         if (!FD_ISSET(purd->fd, &s->rfds))
  63                 return;
  64         bufsize = btr_pool_get_buffer(purd->btrp, &buf);
  65         ret = -E_UDP_OVERRUN;
  66         if (bufsize == 0)
  67                 goto err;
  68         ret = recv_bin_buffer(purd->fd, buf, bufsize);
  69         if (ret == 0)
  70                 ret = -E_RECV_EOF;
  71         if (ret < 0)
  72                 goto err;
  73         packet_size = ret;
  74         if (packet_size >= FEC_EOF_PACKET_LEN) {
  75                 if (!memcmp(buf, FEC_EOF_PACKET, FEC_EOF_PACKET_LEN)) {
  76                         PARA_INFO_LOG("received eof packet\n");
  77                         ret = -E_RECV_EOF;
  78                         goto err;
  79                 }
  80         }
  81         btr_add_output_pool(purd->btrp, packet_size, btrn);
  82         return;
  83 err:
  84         btr_remove_node(btrn);
  85         t->error = ret;
  86         close(purd->fd);
  87         purd->fd = -1;
  88 }
  89
  90 static void udp_recv_close(struct receiver_node *rn)
  91 {
  92         struct private_udp_recv_data *purd = rn->private_data;
  93
  94         if (purd->fd >= 0)
  95                 close(purd->fd);
  96         btr_pool_free(purd->btrp);
  97         free(rn->private_data);
  98 }
  99
 100 static void *udp_recv_parse_config(int argc, char **argv)
 101 {
 102         int ret;
 103         struct udp_recv_args_info *tmp =
 104                 para_calloc(sizeof(struct udp_recv_args_info));
 105
 106         ret = udp_recv_cmdline_parser(argc, argv, tmp)? -E_UDP_SYNTAX : 1;
 107         if (ret >= 0)
 108                 return tmp;
 109         free(tmp);
 110         return NULL;
 111 }
 112
 113 /*
 114  * Perform AF-independent joining of multicast receive addresses.
 115  *
 116  * \param fd    Bound socket descriptor.
 117  * \param iface The receiving multicast interface, or NULL for the default.
 118  *
 119  * \return Zero if okay, negative on error.
 120  */
 121 static int mcast_receiver_setup(int fd, const char *iface)
 122 {
 123         struct sockaddr_storage ss;
 124         socklen_t sslen = sizeof(ss);
 125         int id = iface == NULL ? 0 : if_nametoindex(iface);
 126
 127         if (getsockname(fd, (struct sockaddr *)&ss, &sslen) < 0)
 128                 goto err;
 129
 130         if (iface != NULL && id == 0)
 131                 PARA_WARNING_LOG("could not resolve interface %s, using default", iface);
 132
 133         switch (ss.ss_family) {
 134         case AF_INET:
 135                 if (IN_MULTICAST(htonl(((struct sockaddr_in *)&ss)->sin_addr.s_addr))) {
 136 #ifdef HAVE_IP_MREQN
 137                         struct ip_mreqn m4;
 138
 139                         m4.imr_address.s_addr   = INADDR_ANY;
 140                         m4.imr_ifindex          = id;
 141 #else
 142                         struct ip_mreq m4;
 143
 144                         m4.imr_interface.s_addr = INADDR_ANY;
 145                         if (id != 0)
 146                                 PARA_ERROR_LOG("Setting IPv4 receiver mcast interface not supported.");
 147
 148 #endif
 149                         m4.imr_multiaddr        = ((struct sockaddr_in *)&ss)->sin_addr;
 150
 151                         if (setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &m4, sizeof(m4)) < 0)
 152                                 break;
 153                 }
 154                 return 0;
 155         case AF_INET6:
 156                 if (IN6_IS_ADDR_MULTICAST(&((struct sockaddr_in6 *)&ss)->sin6_addr)) {
 157                         struct ipv6_mreq m6;
 158
 159                         memset(&m6, 0, sizeof(m6));
 160                         memcpy(&m6.ipv6mr_multiaddr, &((struct sockaddr_in6 *)&ss)->sin6_addr, 16);
 161                         m6.ipv6mr_interface = id;
 162                         if (setsockopt(fd, IPPROTO_IPV6, IPV6_JOIN_GROUP, &m6, sizeof(m6)) < 0)
 163                                 break;
 164                 }
 165                 return 0;
 166         default:
 167                 PARA_ERROR_LOG("address family %d not supported", ss.ss_family);
 168                 return -E_ADDRESS_LOOKUP;
 169         }
 170 err:
 171         return -ERRNO_TO_PARA_ERROR(errno);
 172 }
 173
 174 static int udp_recv_open(struct receiver_node *rn)
 175 {
 176         struct private_udp_recv_data *purd;
 177         struct udp_recv_args_info *c = rn->conf;
 178         char  *iface = c->iface_given ? c->iface_arg : NULL;
 179         int ret;
 180
 181         rn->private_data = para_calloc(sizeof(struct private_udp_recv_data));
 182         purd = rn->private_data;
 183
 184         ret = makesock(AF_UNSPEC, IPPROTO_UDP, 1, c->host_arg, c->port_arg);
 185         if (ret < 0)
 186                 goto err;
 187         purd->fd = ret;
 188
 189         ret = mcast_receiver_setup(purd->fd, iface);
 190         if (ret < 0) {
 191                 close(purd->fd);
 192                 return ret;
 193         }
 194
 195         ret = mark_fd_nonblocking(purd->fd);
 196         if (ret < 0) {
 197                 close(purd->fd);
 198                 goto err;
 199         }
 200         PARA_INFO_LOG("receiving from %s:%d, fd=%d\n", c->host_arg,
 201                 c->port_arg, purd->fd);
 202         purd->btrp = btr_pool_new("udp_recv", 320 * 1024);
 203         return purd->fd;
 204 err:
 205         free(rn->private_data);
 206         return ret;
 207 }
 208
 209 static void udp_recv_free_config(void *conf)
 210 {
 211         udp_recv_cmdline_parser_free(conf);
 212 }
 213
 214 /**
 215  * The init function of the udp receiver.
 216  *
 217  * \param r Pointer to the receiver struct to initialize.
 218  *
 219  * Initialize all function pointers of \a r.
 220  */
 221 void udp_recv_init(struct receiver *r)
 222 {
 223         struct udp_recv_args_info dummy;
 224
 225         udp_recv_cmdline_parser_init(&dummy);
 226         r->open = udp_recv_open;
 227         r->close = udp_recv_close;
 228         r->pre_select = udp_recv_pre_select;
 229         r->post_select = udp_recv_post_select;
 230         r->parse_config = udp_recv_parse_config;
 231         r->free_config = udp_recv_free_config;
 232         r->help = (struct ggo_help) {
 233                 .short_help = udp_recv_args_info_help,
 234                 .detailed_help = udp_recv_args_info_detailed_help
 235         };
 236         udp_recv_cmdline_parser_free(&dummy);
 237 }