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                  /* XXX Should log this somehow */
  53                 return;
  54
  55         if (!(handler = authd_stat_handlers[(unsigned char)parv[2][0]]))
  56                 return;
  57
  58         handler(parv[1], parv[2][0]);
  59 }
  60
  61 static void
  62 handle_reload(int parc, char *parv[])
  63 {
  64         authd_reload_handler handler;
  65
  66         if(parc < 2)
  67                  /* XXX Should log this somehow */
  68                 return;
  69
  70         if (!(handler = authd_reload_handlers[(unsigned char)parv[1][0]]))
  71                 return;
  72
  73         handler(parv[1][0]);
  74 }
  75
  76 static void
  77 parse_request(rb_helper *helper)
  78 {
  79         static char *parv[MAXPARA + 1];
  80         static char readbuf[READBUF_SIZE];
  81         int parc;
  82         int len;
  83         authd_cmd_handler handler;
  84
  85         while((len = rb_helper_read(helper, readbuf, sizeof(readbuf))) > 0)
  86         {
  87                 parc = rb_string_to_array(readbuf, parv, MAXPARA);
  88
  89                 if(parc < 1)
  90                         continue;
  91
  92                 handler = authd_cmd_handlers[(unsigned char)parv[0][0]];
  93                 if (handler != NULL)
  94                         handler(parc, parv);
  95         }
  96 }
  97
  98 static void
  99 error_cb(rb_helper *helper)
 100 {
 101         exit(1);
 102 }
 103
 104 #ifndef _WIN32
 105 static void
 106 dummy_handler(int sig)
 107 {
 108         return;
 109 }
 110 #endif
 111
 112 static void
 113 setup_signals(void)
 114 {
 115 #ifndef _WIN32
 116         struct sigaction act;
 117
 118         act.sa_flags = 0;
 119         act.sa_handler = SIG_IGN;
 120         sigemptyset(&act.sa_mask);
 121         sigaddset(&act.sa_mask, SIGPIPE);
 122         sigaddset(&act.sa_mask, SIGALRM);
 123 #ifdef SIGTRAP
 124         sigaddset(&act.sa_mask, SIGTRAP);
 125 #endif
 126
 127 #ifdef SIGWINCH
 128         sigaddset(&act.sa_mask, SIGWINCH);
 129         sigaction(SIGWINCH, &act, 0);
 130 #endif
 131         sigaction(SIGPIPE, &act, 0);
 132 #ifdef SIGTRAP
 133         sigaction(SIGTRAP, &act, 0);
 134 #endif
 135
 136         act.sa_handler = dummy_handler;
 137         sigaction(SIGALRM, &act, 0);
 138 #endif
 139 }
 140
 141 int
 142 main(int argc, char *argv[])
 143 {
 144         setup_signals();
 145
 146         authd_helper = rb_helper_child(parse_request, error_cb, NULL, NULL, NULL, 256, 256, 256);       /* XXX fix me */
 147         if(authd_helper == NULL)
 148         {
 149                 fprintf(stderr, "authd is not meant to be invoked by end users\n");
 150                 exit(1);
 151         }
 152
 153         rb_set_time();
 154         setup_signals();
 155         init_resolver();
 156         init_providers();
 157         rb_init_prng(NULL, RB_PRNG_DEFAULT);
 158
 159         rb_helper_loop(authd_helper, 0);
 160
 161         return 0;
 162 }