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         ['R'] = 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                 /* Reload all handlers */
  71                 for(size_t i = 0; i < sizeof(authd_reload_handlers); i++)
  72                 {
  73                         if ((handler = authd_reload_handlers[(unsigned char) i]) != NULL)
  74                                 handler(parv[1][0]);
  75                 }
  76
  77                 return;
  78         }
  79
  80         if (!(handler = authd_reload_handlers[(unsigned char)parv[1][0]]))
  81                 return;
  82
  83         handler(parv[1][0]);
  84 }
  85
  86 static void
  87 parse_request(rb_helper *helper)
  88 {
  89         static char *parv[MAXPARA + 1];
  90         static char readbuf[READBUF_SIZE];
  91         int parc;
  92         int len;
  93         authd_cmd_handler handler;
  94
  95         while((len = rb_helper_read(helper, readbuf, sizeof(readbuf))) > 0)
  96         {
  97                 parc = rb_string_to_array(readbuf, parv, MAXPARA);
  98
  99                 if(parc < 1)
 100                         continue;
 101
 102                 handler = authd_cmd_handlers[(unsigned char)parv[0][0]];
 103                 if (handler != NULL)
 104                         handler(parc, parv);
 105         }
 106 }
 107
 108 static void
 109 error_cb(rb_helper *helper)
 110 {
 111         exit(1);
 112 }
 113
 114 #ifndef _WIN32
 115 static void
 116 dummy_handler(int sig)
 117 {
 118         return;
 119 }
 120 #endif
 121
 122 static void
 123 setup_signals(void)
 124 {
 125 #ifndef _WIN32
 126         struct sigaction act;
 127
 128         act.sa_flags = 0;
 129         act.sa_handler = SIG_IGN;
 130         sigemptyset(&act.sa_mask);
 131         sigaddset(&act.sa_mask, SIGPIPE);
 132         sigaddset(&act.sa_mask, SIGALRM);
 133 #ifdef SIGTRAP
 134         sigaddset(&act.sa_mask, SIGTRAP);
 135 #endif
 136
 137 #ifdef SIGWINCH
 138         sigaddset(&act.sa_mask, SIGWINCH);
 139         sigaction(SIGWINCH, &act, 0);
 140 #endif
 141         sigaction(SIGPIPE, &act, 0);
 142 #ifdef SIGTRAP
 143         sigaction(SIGTRAP, &act, 0);
 144 #endif
 145
 146         act.sa_handler = dummy_handler;
 147         sigaction(SIGALRM, &act, 0);
 148 #endif
 149 }
 150
 151 int
 152 main(int argc, char *argv[])
 153 {
 154         setup_signals();
 155
 156         authd_helper = rb_helper_child(parse_request, error_cb, NULL, NULL, NULL, 256, 256, 256);       /* XXX fix me */
 157         if(authd_helper == NULL)
 158         {
 159                 fprintf(stderr, "authd is not meant to be invoked by end users\n");
 160                 exit(1);
 161         }
 162
 163         rb_set_time();
 164         setup_signals();
 165         init_resolver();
 166         init_providers();
 167         rb_init_prng(NULL, RB_PRNG_DEFAULT);
 168
 169         rb_helper_loop(authd_helper, 0);
 170
 171         return 0;
 172 }