authd/authd.c

   1 /* authd/authd.c - main code for authd
   2  * Copyright (c) 2016 William Pitcock <nenolod@dereferenced.org>
   3  *
   4  * Permission to use, copy, modify, and/or distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice is present in all copies.
   7  *
   8  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
   9  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  10  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  11  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
  12  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  13  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  14  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  15  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  16  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  17  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  18  * POSSIBILITY OF SUCH DAMAGE.
  19  */
  20
  21 #include "authd.h"
  22 #include "dns.h"
  23
  24 #define MAXPARA 10
  25
  26 static void handle_stat(int parc, char *parv[]);
  27
  28 rb_helper *authd_helper = NULL;
  29 authd_cmd_handler authd_cmd_handlers[255] = {
  30         ['D'] = resolve_dns,
  31         ['S'] = handle_stat,
  32 };
  33
  34 authd_stat_handler authd_stat_handlers[255] = {
  35         ['D'] = enumerate_nameservers,
  36 };
  37
  38 static void
  39 handle_stat(int parc, char *parv[])
  40 {
  41         authd_stat_handler handler;
  42
  43         if(parc < 3)
  44                  /* XXX Should log this somehow */
  45                 return;
  46
  47         if (!(handler = authd_stat_handlers[parv[2][0]]))
  48                 return;
  49
  50         handler(parv[1], parv[2][0]);
  51 }
  52
  53 static void
  54 parse_request(rb_helper *helper)
  55 {
  56         static char *parv[MAXPARA + 1];
  57         static char readbuf[READBUF_SIZE];
  58         int parc;
  59         int len;
  60         authd_cmd_handler handler;
  61
  62         while((len = rb_helper_read(helper, readbuf, sizeof(readbuf))) > 0)
  63         {
  64                 parc = rb_string_to_array(readbuf, parv, MAXPARA);
  65
  66                 if(parc < 1)
  67                         continue;
  68
  69                 handler = authd_cmd_handlers[parv[0][0]];
  70                 if (handler != NULL)
  71                         handler(parc, parv);
  72         }
  73 }
  74
  75 static void
  76 error_cb(rb_helper *helper)
  77 {
  78         exit(1);
  79 }
  80
  81 #ifndef WINDOWS
  82 static void
  83 dummy_handler(int sig)
  84 {
  85         return;
  86 }
  87 #endif
  88
  89 static void
  90 setup_signals(void)
  91 {
  92 #ifndef WINDOWS
  93         struct sigaction act;
  94
  95         act.sa_flags = 0;
  96         act.sa_handler = SIG_IGN;
  97         sigemptyset(&act.sa_mask);
  98         sigaddset(&act.sa_mask, SIGPIPE);
  99         sigaddset(&act.sa_mask, SIGALRM);
 100 #ifdef SIGTRAP
 101         sigaddset(&act.sa_mask, SIGTRAP);
 102 #endif
 103
 104 #ifdef SIGWINCH
 105         sigaddset(&act.sa_mask, SIGWINCH);
 106         sigaction(SIGWINCH, &act, 0);
 107 #endif
 108         sigaction(SIGPIPE, &act, 0);
 109 #ifdef SIGTRAP
 110         sigaction(SIGTRAP, &act, 0);
 111 #endif
 112
 113         act.sa_handler = dummy_handler;
 114         sigaction(SIGALRM, &act, 0);
 115 #endif
 116 }
 117
 118 int
 119 main(int argc, char *argv[])
 120 {
 121         setup_signals();
 122
 123         authd_helper = rb_helper_child(parse_request, error_cb, NULL, NULL, NULL, 256, 256, 256);       /* XXX fix me */
 124         if(authd_helper == NULL)
 125         {
 126                 fprintf(stderr, "authd is not meant to be invoked by end users\n");
 127                 exit(1);
 128         }
 129
 130         rb_set_time();
 131         setup_signals();
 132         init_resolver();
 133         rb_init_prng(NULL, RB_PRNG_DEFAULT);
 134
 135         rb_helper_loop(authd_helper, 0);
 136
 137         return 0;
 138 }