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 "notice.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         ['R'] = handle_reload,
  33         ['D'] = resolve_dns,
  34         ['S'] = handle_stat,
  35 };
  36
  37 authd_stat_handler authd_stat_handlers[256] = {
  38         ['D'] = enumerate_nameservers,
  39 };
  40
  41 authd_reload_handler authd_reload_handlers[256] = {
  42         ['D'] = reload_nameservers,
  43 };
  44
  45 static void
  46 handle_stat(int parc, char *parv[])
  47 {
  48         authd_stat_handler handler;
  49
  50         if(parc < 3)
  51         {
  52                 warn_opers(L_CRIT, "BUG: handle_stat received too few parameters (at least 3 expected, got %d)", parc);
  53                 return;
  54         }
  55
  56         if (!(handler = authd_stat_handlers[(unsigned char)parv[2][0]]))
  57                 return;
  58
  59         handler(parv[1], parv[2][0]);
  60 }
  61
  62 static void
  63 handle_reload(int parc, char *parv[])
  64 {
  65         authd_reload_handler handler;
  66
  67         if(parc < 2)
  68         {
  69                 /* Reload all handlers */
  70                 for(size_t i = 0; i < 256; i++)
  71                 {
  72                         if ((handler = authd_reload_handlers[(unsigned char) i]) != NULL)
  73                                 handler(parv[1][0]);
  74                 }
  75
  76                 return;
  77         }
  78
  79         if (!(handler = authd_reload_handlers[(unsigned char)parv[1][0]]))
  80                 return;
  81
  82         handler(parv[1][0]);
  83 }
  84
  85 static void
  86 parse_request(rb_helper *helper)
  87 {
  88         static char *parv[MAXPARA + 1];
  89         static char readbuf[READBUF_SIZE];
  90         int parc;
  91         int len;
  92         authd_cmd_handler handler;
  93
  94         while((len = rb_helper_read(helper, readbuf, sizeof(readbuf))) > 0)
  95         {
  96                 parc = rb_string_to_array(readbuf, parv, MAXPARA);
  97
  98                 if(parc < 1)
  99                         continue;
 100
 101                 handler = authd_cmd_handlers[(unsigned char)parv[0][0]];
 102                 if (handler != NULL)
 103                         handler(parc, parv);
 104         }
 105 }
 106
 107 static void
 108 error_cb(rb_helper *helper)
 109 {
 110         exit(1);
 111 }
 112
 113 #ifndef _WIN32
 114 static void
 115 dummy_handler(int sig)
 116 {
 117         return;
 118 }
 119 #endif
 120
 121 static void
 122 setup_signals(void)
 123 {
 124 #ifndef _WIN32
 125         struct sigaction act;
 126
 127         act.sa_flags = 0;
 128         act.sa_handler = SIG_IGN;
 129         sigemptyset(&act.sa_mask);
 130         sigaddset(&act.sa_mask, SIGPIPE);
 131         sigaddset(&act.sa_mask, SIGALRM);
 132 #ifdef SIGTRAP
 133         sigaddset(&act.sa_mask, SIGTRAP);
 134 #endif
 135
 136 #ifdef SIGWINCH
 137         sigaddset(&act.sa_mask, SIGWINCH);
 138         sigaction(SIGWINCH, &act, 0);
 139 #endif
 140         sigaction(SIGPIPE, &act, 0);
 141 #ifdef SIGTRAP
 142         sigaction(SIGTRAP, &act, 0);
 143 #endif
 144
 145         act.sa_handler = dummy_handler;
 146         sigaction(SIGALRM, &act, 0);
 147 #endif
 148 }
 149
 150 int
 151 main(int argc, char *argv[])
 152 {
 153         setup_signals();
 154
 155         authd_helper = rb_helper_child(parse_request, error_cb, NULL, NULL, NULL, 256, 256, 256);       /* XXX fix me */
 156         if(authd_helper == NULL)
 157         {
 158                 fprintf(stderr, "authd is not meant to be invoked by end users\n");
 159                 exit(1);
 160         }
 161
 162         rb_set_time();
 163         setup_signals();
 164         init_resolver();
 165         rb_init_prng(NULL, RB_PRNG_DEFAULT);
 166
 167         rb_helper_loop(authd_helper, 0);
 168
 169         return 0;
 170 }