From 1596c1242edddf117266f9996e215d67f06d90c9 Mon Sep 17 00:00:00 2001 From: William Pitcock Date: Wed, 17 Sep 2008 03:23:06 -0500 Subject: [PATCH] Copy ip_cloaking.c to ip_cloaking_3.0.c --- extensions/ip_cloaking_3.0.c | 230 +++++++++++++++++++++++++++++++++++ 1 file changed, 230 insertions(+) create mode 100644 extensions/ip_cloaking_3.0.c diff --git a/extensions/ip_cloaking_3.0.c b/extensions/ip_cloaking_3.0.c new file mode 100644 index 0000000..e80a19a --- /dev/null +++ b/extensions/ip_cloaking_3.0.c @@ -0,0 +1,230 @@ +/* $Id: ip_cloaking.c 3526 2007-07-06 07:56:14Z nenolod $ */ + +#include "stdinc.h" +#include "modules.h" +#include "hook.h" +#include "client.h" +#include "ircd.h" +#include "send.h" +#include "s_conf.h" +#include "s_user.h" +#include "s_serv.h" +#include "numeric.h" + +/* if you're modifying this module, you'll probably to change this */ +#define KEY 0x13748cfa + +static int +_modinit(void) +{ + /* add the usermode to the available slot */ + user_modes['h'] = find_umode_slot(); + construct_umodebuf(); + + return 0; +} + +static void +_moddeinit(void) +{ + /* disable the umode and remove it from the available list */ + user_modes['h'] = 0; + construct_umodebuf(); +} + +static void check_umode_change(void *data); +static void check_new_user(void *data); +mapi_hfn_list_av1 ip_cloaking_hfnlist[] = { + { "umode_changed", (hookfn) check_umode_change }, + { "new_local_user", (hookfn) check_new_user }, + { NULL, NULL } +}; + +DECLARE_MODULE_AV1(ip_cloaking, _modinit, _moddeinit, NULL, NULL, + ip_cloaking_hfnlist, "$Revision: 3526 $"); + +static void +distribute_hostchange(struct Client *client) +{ + if (irccmp(client->host, client->orighost)) + sendto_one_numeric(client, RPL_HOSTHIDDEN, "%s :is now your hidden host", + client->host); + else + sendto_one_numeric(client, RPL_HOSTHIDDEN, "%s :hostname reset", + client->host); + + sendto_server(NULL, NULL, + CAP_EUID | CAP_TS6, NOCAPS, ":%s CHGHOST %s :%s", + use_id(&me), use_id(client), client->host); + sendto_server(NULL, NULL, + CAP_TS6, CAP_EUID, ":%s ENCAP * CHGHOST %s :%s", + use_id(&me), use_id(client), client->host); + if (irccmp(client->host, client->orighost)) + SetDynSpoof(client); + else + ClearDynSpoof(client); +} + +#define Nval 0x8c3a48ac +#define HOSTLEN 63 +#define INITDATA "98fwqefnoiqefv03f423t34gbv3vb89tg432t3b8" /* change this */ + +static inline unsigned int +get_string_entropy(const char *inbuf) +{ + unsigned int accum = 1; + + while(*inbuf != '\0') + accum += *inbuf++; + + return accum; +} + +/* calls get_string_entropy() and toasts it against INITDATA */ +static inline unsigned int +get_string_weighted_entropy(const char *inbuf) +{ + static int base_entropy = 0; + unsigned int accum = get_string_entropy(inbuf); + + /* initialize the algorithm if it is not yet ready */ + if (base_entropy == 0) + base_entropy = get_string_entropy(INITDATA); + + return (Nval * accum) ^ base_entropy; +} + +static void +do_host_cloak_ip(const char *inbuf, char *outbuf) +{ + char *tptr; + unsigned int accum = get_string_weighted_entropy(inbuf); + char buf[HOSTLEN]; + int ipv6 = 0; + + strncpy(buf, inbuf, HOSTLEN); + tptr = strrchr(buf, '.'); + + if (tptr == NULL) + { + tptr = strrchr(buf, ':'); + ipv6 = 1; + } + + if (tptr == NULL) + { + strncpy(outbuf, inbuf, HOSTLEN); + return; + } + + *tptr++ = '\0'; + + if(ipv6) + { + snprintf(outbuf, HOSTLEN, "%s:%x", buf, accum); + } + else + { + snprintf(outbuf, HOSTLEN, "%s.%x", buf, accum); + } +} + +static void +do_host_cloak_host(const char *inbuf, char *outbuf) +{ + char b26_alphabet[] = "abcdefghijklmnopqrstuvwxyz"; + char *tptr; + unsigned int accum = get_string_weighted_entropy(inbuf); + + strncpy(outbuf, inbuf, HOSTLEN); + + /* pass 1: scramble first section of hostname using base26 + * alphabet toasted against the weighted entropy of the string. + * + * numbers are not changed at this time, only letters. + */ + for (tptr = outbuf; *tptr != '\0'; tptr++) + { + if (*tptr == '.') + break; + + if (isdigit(*tptr) || *tptr == '-') + continue; + + *tptr = b26_alphabet[(*tptr * accum) % 26]; + } + + /* pass 2: scramble each number in the address */ + for (tptr = outbuf; *tptr != '\0'; tptr++) + { + if (isdigit(*tptr)) + { + *tptr = 48 + ((*tptr * accum) % 10); + } + } +} + +static void +check_umode_change(void *vdata) +{ + hook_data_umode_changed *data = (hook_data_umode_changed *)vdata; + struct Client *source_p = data->client; + + if (!MyClient(source_p)) + return; + + /* didn't change +h umode, we don't need to do anything */ + if (!((data->oldumodes ^ source_p->umodes) & user_modes['h'])) + return; + + if (source_p->umodes & user_modes['h']) + { + if (IsIPSpoof(source_p) || source_p->localClient->mangledhost == NULL || (IsDynSpoof(source_p) && strcmp(source_p->host, source_p->localClient->mangledhost))) + { + source_p->umodes &= ~user_modes['h']; + return; + } + if (strcmp(source_p->host, source_p->localClient->mangledhost)) + { + rb_strlcpy(source_p->host, source_p->localClient->mangledhost, HOSTLEN); + distribute_hostchange(source_p); + } + else /* not really nice, but we need to send this numeric here */ + sendto_one_numeric(source_p, RPL_HOSTHIDDEN, "%s :is now your hidden host", + source_p->host); + } + else if (!(source_p->umodes & user_modes['h'])) + { + if (source_p->localClient->mangledhost != NULL && + !strcmp(source_p->host, source_p->localClient->mangledhost)) + { + rb_strlcpy(source_p->host, source_p->orighost, HOSTLEN); + distribute_hostchange(source_p); + } + } +} + +static void +check_new_user(void *vdata) +{ + struct Client *source_p = (void *)vdata; + + if (IsIPSpoof(source_p)) + { + source_p->umodes &= ~user_modes['h']; + return; + } + source_p->localClient->mangledhost = rb_malloc(HOSTLEN); + if (!irccmp(source_p->orighost, source_p->sockhost)) + do_host_cloak_ip(source_p->orighost, source_p->localClient->mangledhost); + else + do_host_cloak_host(source_p->orighost, source_p->localClient->mangledhost); + if (IsDynSpoof(source_p)) + source_p->umodes &= ~user_modes['h']; + if (source_p->umodes & user_modes['h']) + { + rb_strlcpy(source_p->host, source_p->localClient->mangledhost, sizeof(source_p->host)); + if (irccmp(source_p->host, source_p->orighost)) + SetDynSpoof(source_p); + } +}