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 #include "provider.h"
  24
  25 #define MAXPARA 10
  26
  27 static void handle_reload(int parc, char *parv[]);
  28 static void handle_stat(int parc, char *parv[]);
  29
  30 rb_helper *authd_helper = NULL;
  31 authd_cmd_handler authd_cmd_handlers[256] = {
  32         ['C'] = handle_new_connection,
  33         ['D'] = resolve_dns,
  34         ['H'] = handle_reload,
  35         ['S'] = handle_stat,
  36 };
  37
  38 authd_stat_handler authd_stat_handlers[256] = {
  39         ['D'] = enumerate_nameservers,
  40 };
  41
  42 authd_reload_handler authd_reload_handlers[256] = {
  43         ['D'] = reload_nameservers,
  44 };
  45
  46 static void
  47 handle_stat(int parc, char *parv[])
  48 {
  49         authd_stat_handler handler;
  50
  51         if(parc < 3)
  52         {
  53                 warn_opers(L_CRIT, "BUG: handle_stat received too few parameters (at least 3 expected, got %d)", parc);
  54                 return;
  55         }
  56
  57         if (!(handler = authd_stat_handlers[(unsigned char)parv[2][0]]))
  58                 return;
  59
  60         handler(parv[1], parv[2][0]);
  61 }
  62
  63 static void
  64 handle_reload(int parc, char *parv[])
  65 {
  66         authd_reload_handler handler;
  67
  68         if(parc < 2)
  69         {
  70                 warn_opers(L_CRIT, "BUG: handle_reload received too few parameters (at least 2 expected, got %d)", parc);
  71                 return;
  72         }
  73
  74         if (!(handler = authd_reload_handlers[(unsigned char)parv[1][0]]))
  75                 return;
  76
  77         handler(parv[1][0]);
  78 }
  79
  80 static void
  81 parse_request(rb_helper *helper)
  82 {
  83         static char *parv[MAXPARA + 1];
  84         static char readbuf[READBUF_SIZE];
  85         int parc;
  86         int len;
  87         authd_cmd_handler handler;
  88
  89         while((len = rb_helper_read(helper, readbuf, sizeof(readbuf))) > 0)
  90         {
  91                 parc = rb_string_to_array(readbuf, parv, MAXPARA);
  92
  93                 if(parc < 1)
  94                         continue;
  95
  96                 handler = authd_cmd_handlers[(unsigned char)parv[0][0]];
  97                 if (handler != NULL)
  98                         handler(parc, parv);
  99         }
 100 }
 101
 102 static void
 103 error_cb(rb_helper *helper)
 104 {
 105         exit(1);
 106 }
 107
 108 #ifndef _WIN32
 109 static void
 110 dummy_handler(int sig)
 111 {
 112         return;
 113 }
 114 #endif
 115
 116 static void
 117 setup_signals(void)
 118 {
 119 #ifndef _WIN32
 120         struct sigaction act;
 121
 122         act.sa_flags = 0;
 123         act.sa_handler = SIG_IGN;
 124         sigemptyset(&act.sa_mask);
 125         sigaddset(&act.sa_mask, SIGPIPE);
 126         sigaddset(&act.sa_mask, SIGALRM);
 127 #ifdef SIGTRAP
 128         sigaddset(&act.sa_mask, SIGTRAP);
 129 #endif
 130
 131 #ifdef SIGWINCH
 132         sigaddset(&act.sa_mask, SIGWINCH);
 133         sigaction(SIGWINCH, &act, 0);
 134 #endif
 135         sigaction(SIGPIPE, &act, 0);
 136 #ifdef SIGTRAP
 137         sigaction(SIGTRAP, &act, 0);
 138 #endif
 139
 140         act.sa_handler = dummy_handler;
 141         sigaction(SIGALRM, &act, 0);
 142 #endif
 143 }
 144
 145 int
 146 main(int argc, char *argv[])
 147 {
 148         setup_signals();
 149
 150         authd_helper = rb_helper_child(parse_request, error_cb, NULL, NULL, NULL, 256, 256, 256);       /* XXX fix me */
 151         if(authd_helper == NULL)
 152         {
 153                 fprintf(stderr, "authd is not meant to be invoked by end users\n");
 154                 exit(1);
 155         }
 156
 157         rb_set_time();
 158         setup_signals();
 159         init_resolver();
 160         init_providers();
 161         rb_init_prng(NULL, RB_PRNG_DEFAULT);
 162
 163         rb_helper_loop(authd_helper, 0);
 164
 165         return 0;
 166 }