extensions/ip_cloaking_old.c

   1
   2 #include "stdinc.h"
   3 #include "modules.h"
   4 #include "hook.h"
   5 #include "client.h"
   6 #include "ircd.h"
   7 #include "send.h"
   8 #include "s_conf.h"
   9 #include "s_user.h"
  10 #include "s_serv.h"
  11 #include "numeric.h"
  12
  13 static const char ip_cloaking_desc[] = "Very old IP cloaking mechanism";
  14
  15 /* if you're modifying this module, you'll probably want to change this */
  16 #define KEY 0x13748cfa
  17
  18 static int
  19 _modinit(void)
  20 {
  21         /* add the usermode to the available slot */
  22         user_modes['h'] = find_umode_slot();
  23         construct_umodebuf();
  24
  25         return 0;
  26 }
  27
  28 static void
  29 _moddeinit(void)
  30 {
  31         /* disable the umode and remove it from the available list */
  32         user_modes['h'] = 0;
  33         construct_umodebuf();
  34 }
  35
  36 static void check_umode_change(void *data);
  37 static void check_new_user(void *data);
  38 mapi_hfn_list_av1 ip_cloaking_hfnlist[] = {
  39         { "umode_changed", check_umode_change },
  40         { "new_local_user", check_new_user },
  41         { NULL, NULL }
  42 };
  43
  44 DECLARE_MODULE_AV2(ip_cloaking, _modinit, _moddeinit, NULL, NULL,
  45                         ip_cloaking_hfnlist, NULL, NULL, ip_cloaking_desc);
  46
  47 static void
  48 distribute_hostchange(struct Client *client_p, char *newhost)
  49 {
  50         if (newhost != client_p->orighost)
  51                 sendto_one_numeric(client_p, RPL_HOSTHIDDEN, "%s :is now your hidden host",
  52                         newhost);
  53         else
  54                 sendto_one_numeric(client_p, RPL_HOSTHIDDEN, "%s :hostname reset",
  55                         newhost);
  56
  57         sendto_server(NULL, NULL,
  58                 CAP_EUID | CAP_TS6, NOCAPS, ":%s CHGHOST %s :%s",
  59                 use_id(&me), use_id(client_p), newhost);
  60         sendto_server(NULL, NULL,
  61                 CAP_TS6, CAP_EUID, ":%s ENCAP * CHGHOST %s :%s",
  62                 use_id(&me), use_id(client_p), newhost);
  63
  64         change_nick_user_host(client_p, client_p->name, client_p->username, newhost, 0, "Changing host");
  65
  66         if (newhost != client_p->orighost)
  67                 SetDynSpoof(client_p);
  68         else
  69                 ClearDynSpoof(client_p);
  70 }
  71
  72 static void
  73 do_host_cloak(const char *inbuf, char *outbuf, int ipmask)
  74 {
  75         unsigned int cyc;
  76         unsigned int hosthash = 1, hosthash2 = 1;
  77         unsigned int maxcycle = strlen(inbuf);
  78         int len1;
  79         const char *rest, *next;
  80
  81         for (cyc = 0; cyc < maxcycle - 2; cyc += 2)
  82                 hosthash *= (unsigned int) inbuf[cyc];
  83
  84         /* safety: decrement ourselves two steps back */
  85         for (cyc = maxcycle - 1; cyc >= 1; cyc -= 2)
  86                 hosthash2 *= (unsigned int) inbuf[cyc];
  87
  88         /* lets do some bitshifting -- this pretty much destroys the IP
  89          * sequence, while still providing a checksum. exactly what
  90          * we're shooting for. --nenolod
  91          */
  92         hosthash += (hosthash2 / KEY);
  93         hosthash2 += (hosthash / KEY);
  94
  95         if (ipmask == 0)
  96         {
  97                 snprintf(outbuf, HOSTLEN, "%s-%X%X",
  98                         ServerInfo.network_name, hosthash2, hosthash);
  99                 len1 = strlen(outbuf);
 100                 rest = strchr(inbuf, '.');
 101                 if (rest == NULL)
 102                         rest = ".";
 103                 /* try to avoid truncation -- jilles */
 104                 while (len1 + strlen(rest) >= HOSTLEN && (next = strchr(rest + 1, '.')) != NULL)
 105                         rest = next;
 106                 rb_strlcat(outbuf, rest, HOSTLEN);
 107         }
 108         else
 109                 snprintf(outbuf, HOSTLEN, "%X%X.%s",
 110                         hosthash2, hosthash, ServerInfo.network_name);
 111 }
 112
 113 static void
 114 check_umode_change(void *vdata)
 115 {
 116         hook_data_umode_changed *data = (hook_data_umode_changed *)vdata;
 117         struct Client *source_p = data->client;
 118
 119         if (!MyClient(source_p))
 120                 return;
 121
 122         /* didn't change +h umode, we don't need to do anything */
 123         if (!((data->oldumodes ^ source_p->umodes) & user_modes['h']))
 124                 return;
 125
 126         if (source_p->umodes & user_modes['h'])
 127         {
 128                 if (IsIPSpoof(source_p) || source_p->localClient->mangledhost == NULL || (IsDynSpoof(source_p) && strcmp(source_p->host, source_p->localClient->mangledhost)))
 129                 {
 130                         source_p->umodes &= ~user_modes['h'];
 131                         return;
 132                 }
 133                 if (strcmp(source_p->host, source_p->localClient->mangledhost))
 134                 {
 135                         distribute_hostchange(source_p, source_p->localClient->mangledhost);
 136                 }
 137                 else /* not really nice, but we need to send this numeric here */
 138                         sendto_one_numeric(source_p, RPL_HOSTHIDDEN, "%s :is now your hidden host",
 139                                 source_p->host);
 140         }
 141         else if (!(source_p->umodes & user_modes['h']))
 142         {
 143                 if (source_p->localClient->mangledhost != NULL &&
 144                                 !strcmp(source_p->host, source_p->localClient->mangledhost))
 145                 {
 146                         distribute_hostchange(source_p, source_p->orighost);
 147                 }
 148         }
 149 }
 150
 151 static void
 152 check_new_user(void *vdata)
 153 {
 154         struct Client *source_p = (void *)vdata;
 155
 156         if (IsIPSpoof(source_p))
 157         {
 158                 source_p->umodes &= ~user_modes['h'];
 159                 return;
 160         }
 161         source_p->localClient->mangledhost = rb_malloc(HOSTLEN + 1);
 162         if (!irccmp(source_p->orighost, source_p->sockhost))
 163                 do_host_cloak(source_p->orighost, source_p->localClient->mangledhost, 1);
 164         else
 165                 do_host_cloak(source_p->orighost, source_p->localClient->mangledhost, 0);
 166         if (IsDynSpoof(source_p))
 167                 source_p->umodes &= ~user_modes['h'];
 168         if (source_p->umodes & user_modes['h'])
 169         {
 170                 rb_strlcpy(source_p->host, source_p->localClient->mangledhost, sizeof(source_p->host));
 171                 if (irccmp(source_p->host, source_p->orighost))
 172                         SetDynSpoof(source_p);
 173         }
 174 }