dccp_recv.c

   1 /*
   2  * Copyright (C) 2006-2013 Andre Noll <maan@systemlinux.org>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6
   7 /** \file dccp_recv.c paraslash's dccp receiver */
   8
   9 /*
  10  * based on client.c of dccp-cs-0.01.tar.bz2,
  11  * (C) 2005 Ian McDonald <imcdnzl@gmail.com>
  12  */
  13
  14 #include <netinet/in.h>
  15 #include <sys/socket.h>
  16 #include <regex.h>
  17 #include <sys/types.h>
  18 #include <arpa/inet.h>
  19 #include <sys/un.h>
  20 #include <netdb.h>
  21
  22 #include "para.h"
  23 #include "error.h"
  24 #include "list.h"
  25 #include "sched.h"
  26 #include "ggo.h"
  27 #include "buffer_tree.h"
  28 #include "recv.h"
  29 #include "string.h"
  30 #include "net.h"
  31 #include "fd.h"
  32
  33 #include "dccp_recv.cmdline.h"
  34
  35 static void dccp_recv_close(struct receiver_node *rn)
  36 {
  37         if (rn->fd > 0)
  38                 close(rn->fd);
  39         btr_pool_free(rn->btrp);
  40 }
  41
  42 static int dccp_recv_open(struct receiver_node *rn)
  43 {
  44         struct dccp_recv_args_info *conf = rn->conf;
  45         struct flowopts *fo = NULL;
  46         uint8_t *ccids = NULL;
  47         int fd, ret, i;
  48
  49         /* Copy CCID preference list (u8 array required) */
  50         if (conf->ccid_given) {
  51                 ccids = para_malloc(conf->ccid_given);
  52                 fo    = flowopt_new();
  53
  54                 for (i = 0; i < conf->ccid_given; i++)
  55                         ccids[i] = conf->ccid_arg[i];
  56
  57                 OPT_ADD(fo, SOL_DCCP, DCCP_SOCKOPT_CCID, ccids, i);
  58         }
  59
  60         fd = makesock(IPPROTO_DCCP, 0, conf->host_arg, conf->port_arg, fo);
  61         free(ccids);
  62         if (fd < 0)
  63                 return fd;
  64         /*
  65          * Disable unused CCIDs: the receiver does not send any application
  66          * data to the server. By shutting down this unused path we reduce
  67          * internal processing costs, as the unused CCIDs (in the kernel) are
  68          * then bypassed.
  69          */
  70         if (shutdown(fd, SHUT_WR) < 0) {
  71                 ret = -ERRNO_TO_PARA_ERROR(errno);
  72                 goto err;
  73         }
  74         ret = mark_fd_nonblocking(fd);
  75         if (ret < 0)
  76                 goto err;
  77         rn->btrp = btr_pool_new("dccp_recv", 320 * 1024);
  78         rn->fd = fd;
  79         return 1;
  80 err:
  81         close(fd);
  82         return ret;
  83 }
  84
  85 /**
  86  * Check whether the host supports the requested 'ccid' arguments.
  87  * \param conf DCCP receiver arguments.
  88  * \return True if all CCIDs requested in \a conf are supported.
  89  */
  90 static bool dccp_recv_ccid_support_check(struct dccp_recv_args_info *conf)
  91 {
  92         uint8_t *ccids;
  93         int i, j, nccids;
  94
  95         nccids = dccp_available_ccids(&ccids);
  96         if (nccids <= 0)
  97                 return false;
  98
  99         for (i = 0; i < conf->ccid_given; i++) {
 100                 for (j = 0; j < nccids && ccids[j] != conf->ccid_arg[i]; j++)
 101                         ;
 102                 if (j == nccids) {
 103                         PARA_ERROR_LOG("'CCID-%d' not supported on this host.\n",
 104                                         conf->ccid_arg[i]);
 105                         return false;
 106                 }
 107         }
 108         return true;
 109 }
 110
 111 static void *dccp_recv_parse_config(int argc, char **argv)
 112 {
 113         struct dccp_recv_args_info *tmp = para_calloc(sizeof(*tmp));
 114
 115         dccp_recv_cmdline_parser(argc, argv, tmp);
 116         if (!dccp_recv_ccid_support_check(tmp))
 117                 exit(EXIT_FAILURE);
 118         return tmp;
 119 }
 120
 121 static void dccp_recv_pre_select(struct sched *s, struct task *t)
 122 {
 123         struct receiver_node *rn = container_of(t, struct receiver_node, task);
 124
 125         t->error = 0;
 126         if (generic_recv_pre_select(s, t) <= 0)
 127                 return;
 128         para_fd_set(rn->fd, &s->rfds, &s->max_fileno);
 129 }
 130
 131 static int dccp_recv_post_select(struct sched *s, struct task *t)
 132 {
 133         struct receiver_node *rn = container_of(t, struct receiver_node, task);
 134         struct btr_node *btrn = rn->btrn;
 135         struct iovec iov[2];
 136         int ret, iovcnt;
 137         size_t num_bytes;
 138
 139         ret = task_get_notification(t);
 140         if (ret < 0)
 141                 goto out;
 142         ret = btr_node_status(btrn, 0, BTR_NT_ROOT);
 143         if (ret <= 0)
 144                 goto out;
 145         iovcnt = btr_pool_get_buffers(rn->btrp, iov);
 146         ret = -E_DCCP_OVERRUN;
 147         if (iovcnt == 0)
 148                 goto out;
 149         ret = readv_nonblock(rn->fd, iov, iovcnt, &s->rfds, &num_bytes);
 150         if (num_bytes == 0)
 151                 goto out;
 152         if (num_bytes <= iov[0].iov_len) /* only the first buffer was filled */
 153                 btr_add_output_pool(rn->btrp, num_bytes, btrn);
 154         else { /* both buffers contain data */
 155                 btr_add_output_pool(rn->btrp, iov[0].iov_len, btrn);
 156                 btr_add_output_pool(rn->btrp, num_bytes - iov[0].iov_len, btrn);
 157         }
 158 out:
 159         if (ret < 0)
 160                 btr_remove_node(&rn->btrn);
 161         return ret;
 162 }
 163
 164 static void dccp_recv_free_config(void *conf)
 165 {
 166         dccp_recv_cmdline_parser_free(conf);
 167         free(conf);
 168 }
 169
 170 /**
 171  * The init function of the dccp receiver.
 172  *
 173  * \param r Pointer to the receiver struct to initialize.
 174  *
 175  * Initialize all function pointers of \a r.
 176  */
 177 void dccp_recv_init(struct receiver *r)
 178 {
 179         struct dccp_recv_args_info dummy;
 180
 181         dccp_recv_cmdline_parser_init(&dummy);
 182         r->open = dccp_recv_open;
 183         r->close = dccp_recv_close;
 184         r->pre_select = dccp_recv_pre_select;
 185         r->post_select = dccp_recv_post_select;
 186         r->parse_config = dccp_recv_parse_config;
 187         r->free_config = dccp_recv_free_config;
 188         r->help = (struct ggo_help)DEFINE_GGO_HELP(dccp_recv);
 189         dccp_recv_cmdline_parser_free(&dummy);
 190 }