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 /** The size of the receiver node buffer. */
  27 #define UDP_RECV_CHUNK_SIZE (128 * 1024)
  28 /**
  29  * Data specific to the udp receiver.
  30  *
  31  * \sa \ref receiver, \ref receiver_node.
  32  */
  33 struct private_udp_recv_data {
  34         /** The socket file descriptor. */
  35         int fd;
  36         struct btr_pool *btrp;
  37 };
  38
  39 static void udp_recv_pre_select(struct sched *s, struct task *t)
  40 {
  41         struct receiver_node *rn = container_of(t, struct receiver_node, task);
  42         struct private_udp_recv_data *purd = rn->private_data;
  43
  44         if (generic_recv_pre_select(s, t) <= 0)
  45                 return;
  46         para_fd_set(purd->fd, &s->rfds, &s->max_fileno);
  47 }
  48
  49 static void udp_recv_post_select(__a_unused struct sched *s, struct task *t)
  50 {
  51         struct receiver_node *rn = container_of(t, struct receiver_node, task);
  52         struct private_udp_recv_data *purd = rn->private_data;
  53         struct btr_node *btrn = rn->btrn;
  54         int ret;
  55         char *buf = NULL;
  56         size_t packet_size, bufsize;
  57
  58         t->error = 0;
  59         ret = btr_node_status(btrn, 0, BTR_NT_ROOT);
  60         if (ret < 0)
  61                 goto err;
  62         if (ret == 0)
  63                 return;
  64         if (!FD_ISSET(purd->fd, &s->rfds))
  65                 return;
  66         bufsize = btr_pool_get_buffer(purd->btrp, &buf);
  67         ret = -E_UDP_OVERRUN;
  68         if (bufsize == 0)
  69                 goto err;
  70         ret = recv_bin_buffer(purd->fd, buf, bufsize);
  71         if (ret == 0)
  72                 ret = -E_RECV_EOF;
  73         if (ret < 0)
  74                 goto err;
  75         packet_size = ret;
  76         if (packet_size >= FEC_EOF_PACKET_LEN) {
  77                 if (!memcmp(buf, FEC_EOF_PACKET, FEC_EOF_PACKET_LEN)) {
  78                         PARA_INFO_LOG("received eof packet\n");
  79                         ret = -E_RECV_EOF;
  80                         goto err;
  81                 }
  82         }
  83         btr_add_output_pool(purd->btrp, packet_size, btrn);
  84         return;
  85 err:
  86         btr_remove_node(btrn);
  87         t->error = ret;
  88         close(purd->fd);
  89         purd->fd = -1;
  90 }
  91
  92 static void udp_recv_close(struct receiver_node *rn)
  93 {
  94         struct private_udp_recv_data *purd = rn->private_data;
  95
  96         if (purd->fd >= 0)
  97                 close(purd->fd);
  98         btr_pool_free(purd->btrp);
  99         free(rn->private_data);
 100         free(rn->buf);
 101 }
 102
 103 static void *udp_recv_parse_config(int argc, char **argv)
 104 {
 105         int ret;
 106         struct udp_recv_args_info *tmp =
 107                 para_calloc(sizeof(struct udp_recv_args_info));
 108
 109         ret = udp_recv_cmdline_parser(argc, argv, tmp)? -E_UDP_SYNTAX : 1;
 110         if (ret >= 0)
 111                 return tmp;
 112         free(tmp);
 113         return NULL;
 114 }
 115
 116 /*
 117  * Perform AF-independent joining of multicast receive addresses.
 118  *
 119  * \param fd    Bound socket descriptor.
 120  * \param iface The receiving multicast interface, or NULL for the default.
 121  *
 122  * \return Zero if okay, negative on error.
 123  */
 124 static int mcast_receiver_setup(int fd, const char *iface)
 125 {
 126         struct sockaddr_storage ss;
 127         socklen_t sslen = sizeof(ss);
 128         int id = iface == NULL ? 0 : if_nametoindex(iface);
 129
 130         if (getsockname(fd, (struct sockaddr *)&ss, &sslen) < 0)
 131                 goto err;
 132
 133         if (iface != NULL && id == 0)
 134                 PARA_WARNING_LOG("could not resolve interface %s, using default", iface);
 135
 136         switch (ss.ss_family) {
 137         case AF_INET:
 138                 if (IN_MULTICAST(htonl(((struct sockaddr_in *)&ss)->sin_addr.s_addr))) {
 139 #ifdef HAVE_IP_MREQN
 140                         struct ip_mreqn m4;
 141
 142                         m4.imr_address.s_addr   = INADDR_ANY;
 143                         m4.imr_ifindex          = id;
 144 #else
 145                         struct ip_mreq m4;
 146
 147                         m4.imr_interface.s_addr = INADDR_ANY;
 148                         if (id != 0)
 149                                 PARA_ERROR_LOG("Setting IPv4 receiver mcast interface not supported.");
 150
 151 #endif
 152                         m4.imr_multiaddr        = ((struct sockaddr_in *)&ss)->sin_addr;
 153
 154                         if (setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &m4, sizeof(m4)) < 0)
 155                                 break;
 156                 }
 157                 return 0;
 158         case AF_INET6:
 159                 if (IN6_IS_ADDR_MULTICAST(&((struct sockaddr_in6 *)&ss)->sin6_addr)) {
 160                         struct ipv6_mreq m6;
 161
 162                         memset(&m6, 0, sizeof(m6));
 163                         memcpy(&m6.ipv6mr_multiaddr, &((struct sockaddr_in6 *)&ss)->sin6_addr, 16);
 164                         m6.ipv6mr_interface = id;
 165                         if (setsockopt(fd, IPPROTO_IPV6, IPV6_JOIN_GROUP, &m6, sizeof(m6)) < 0)
 166                                 break;
 167                 }
 168                 return 0;
 169         default:
 170                 PARA_ERROR_LOG("address family %d not supported", ss.ss_family);
 171                 return -E_ADDRESS_LOOKUP;
 172         }
 173 err:
 174         return -ERRNO_TO_PARA_ERROR(errno);
 175 }
 176
 177 static int udp_recv_open(struct receiver_node *rn)
 178 {
 179         struct private_udp_recv_data *purd;
 180         struct udp_recv_args_info *c = rn->conf;
 181         char  *iface = c->iface_given ? c->iface_arg : NULL;
 182         int ret;
 183
 184         rn->buf = para_calloc(UDP_RECV_CHUNK_SIZE);
 185         rn->private_data = para_calloc(sizeof(struct private_udp_recv_data));
 186         purd = rn->private_data;
 187
 188         ret = makesock(AF_UNSPEC, IPPROTO_UDP, 1, c->host_arg, c->port_arg);
 189         if (ret < 0)
 190                 goto err;
 191         purd->fd = ret;
 192
 193         ret = mcast_receiver_setup(purd->fd, iface);
 194         if (ret < 0) {
 195                 close(purd->fd);
 196                 return ret;
 197         }
 198
 199         ret = mark_fd_nonblocking(purd->fd);
 200         if (ret < 0) {
 201                 close(purd->fd);
 202                 goto err;
 203         }
 204         PARA_INFO_LOG("receiving from %s:%d, fd=%d\n", c->host_arg,
 205                 c->port_arg, purd->fd);
 206         purd->btrp = btr_pool_new("udp_recv", 320 * 1024);
 207         return purd->fd;
 208 err:
 209         free(rn->private_data);
 210         free(rn->buf);
 211         return ret;
 212 }
 213
 214 static void udp_recv_free_config(void *conf)
 215 {
 216         udp_recv_cmdline_parser_free(conf);
 217 }
 218
 219 /**
 220  * The init function of the udp receiver.
 221  *
 222  * \param r Pointer to the receiver struct to initialize.
 223  *
 224  * Initialize all function pointers of \a r.
 225  */
 226 void udp_recv_init(struct receiver *r)
 227 {
 228         struct udp_recv_args_info dummy;
 229
 230         udp_recv_cmdline_parser_init(&dummy);
 231         r->open = udp_recv_open;
 232         r->close = udp_recv_close;
 233         r->pre_select = udp_recv_pre_select;
 234         r->post_select = udp_recv_post_select;
 235         r->parse_config = udp_recv_parse_config;
 236         r->free_config = udp_recv_free_config;
 237         r->help = (struct ggo_help) {
 238                 .short_help = udp_recv_args_info_help,
 239                 .detailed_help = udp_recv_args_info_detailed_help
 240         };
 241         udp_recv_cmdline_parser_free(&dummy);
 242 }