X-Git-Url: https://jfr.im/git/solanum.git/blobdiff_plain/954012d39be2c96c55f6939e69edd8aa90495820..eeabf33a7c34efbedce519f67b8b87e4c75a422f:/extensions/ip_cloaking.c diff --git a/extensions/ip_cloaking.c b/extensions/ip_cloaking.c index 1b5af63c..a650c8ab 100644 --- a/extensions/ip_cloaking.c +++ b/extensions/ip_cloaking.c @@ -1,4 +1,9 @@ -/* $Id: ip_cloaking.c 3526 2007-07-06 07:56:14Z nenolod $ */ +/* + * Charybdis: an advanced ircd + * ip_cloaking.c: provide user hostname cloaking + * + * Written originally by nenolod, altered to use FNV by Elizabeth in 2008 + */ #include "stdinc.h" #include "modules.h" @@ -6,13 +11,13 @@ #include "client.h" #include "ircd.h" #include "send.h" +#include "hash.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 const char ip_cloaking_desc[] = "IP cloaking module that uses user mode +h"; static int _modinit(void) @@ -40,82 +45,83 @@ mapi_hfn_list_av1 ip_cloaking_hfnlist[] = { { NULL, NULL } }; -DECLARE_MODULE_AV1(ip_cloaking, _modinit, _moddeinit, NULL, NULL, - ip_cloaking_hfnlist, "$Revision: 3526 $"); +DECLARE_MODULE_AV2(ip_cloaking, _modinit, _moddeinit, NULL, NULL, + ip_cloaking_hfnlist, NULL, NULL, ip_cloaking_desc); static void -distribute_hostchange(struct Client *client) +distribute_hostchange(struct Client *client_p, char *newhost) { - if (irccmp(client->host, client->orighost)) - sendto_one_numeric(client, RPL_HOSTHIDDEN, "%s :is now your hidden host", - client->host); + if (newhost != client_p->orighost) + sendto_one_numeric(client_p, RPL_HOSTHIDDEN, "%s :is now your hidden host", + newhost); else - sendto_one_numeric(client, RPL_HOSTHIDDEN, "%s :hostname reset", - client->host); + sendto_one_numeric(client_p, RPL_HOSTHIDDEN, "%s :hostname reset", + newhost); sendto_server(NULL, NULL, CAP_EUID | CAP_TS6, NOCAPS, ":%s CHGHOST %s :%s", - use_id(&me), use_id(client), client->host); + use_id(&me), use_id(client_p), newhost); sendto_server(NULL, NULL, CAP_TS6, CAP_EUID, ":%s ENCAP * CHGHOST %s :%s", - use_id(&me), use_id(client), client->host); - sendto_server(NULL, NULL, - NOCAPS, CAP_TS6, ":%s ENCAP * CHGHOST %s :%s", - me.name, client->name, client->host); - if (irccmp(client->host, client->orighost)) - SetDynSpoof(client); - else - ClearDynSpoof(client); -} - -#define Nval 0x8c3a48ac -#define HOSTLEN 63 -#define INITDATA "98fwqefnoiqefv03f423t34gbv3vb89tg432t3b8" /* change this */ + use_id(&me), use_id(client_p), newhost); -static inline unsigned int -get_string_entropy(const char *inbuf) -{ - unsigned int accum = 1; - - while(*inbuf != '\0') - accum += *inbuf++; - - return accum; -} + change_nick_user_host(client_p, client_p->name, client_p->username, newhost, 0, "Changing host"); -/* 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; + if (newhost != client_p->orighost) + SetDynSpoof(client_p); + else + ClearDynSpoof(client_p); } static void do_host_cloak_ip(const char *inbuf, char *outbuf) { + /* None of the characters in this table can be valid in an IP */ + char chartable[] = "ghijklmnopqrstuvwxyz"; char *tptr; - unsigned int accum = get_string_weighted_entropy(inbuf); - char buf[HOSTLEN]; + uint32_t accum = fnv_hash((const unsigned char*) inbuf, 32); + int sepcount = 0; + int totalcount = 0; + int ipv6 = 0; - strncpy(buf, inbuf, HOSTLEN); - tptr = strrchr(buf, '.'); + rb_strlcpy(outbuf, inbuf, HOSTLEN + 1); - if (tptr == NULL) + if (strchr(outbuf, ':')) { - strncpy(outbuf, inbuf, HOSTLEN); - return; + ipv6 = 1; + + /* Damn you IPv6... + * We count the number of colons so we can calculate how much + * of the host to cloak. This is because some hostmasks may not + * have as many octets as we'd like. + * + * We have to do this ahead of time because doing this during + * the actual cloaking would get ugly + */ + for (tptr = outbuf; *tptr != '\0'; tptr++) + if (*tptr == ':') + totalcount++; } + else if (!strchr(outbuf, '.')) + return; - *tptr++ = '\0'; + for (tptr = outbuf; *tptr != '\0'; tptr++) + { + if (*tptr == ':' || *tptr == '.') + { + sepcount++; + continue; + } + + if (ipv6 && sepcount < totalcount / 2) + continue; + + if (!ipv6 && sepcount < 2) + continue; - snprintf(outbuf, HOSTLEN, "%s.%x", buf, accum); + *tptr = chartable[(*tptr + accum) % 20]; + accum = (accum << 1) | (accum >> 31); + } } static void @@ -123,12 +129,12 @@ do_host_cloak_host(const char *inbuf, char *outbuf) { char b26_alphabet[] = "abcdefghijklmnopqrstuvwxyz"; char *tptr; - unsigned int accum = get_string_weighted_entropy(inbuf); + uint32_t accum = fnv_hash((const unsigned char*) inbuf, 32); - strncpy(outbuf, inbuf, HOSTLEN); + rb_strlcpy(outbuf, inbuf, HOSTLEN + 1); - /* pass 1: scramble first section of hostname using base26 - * alphabet toasted against the weighted entropy of the string. + /* pass 1: scramble first section of hostname using base26 + * alphabet toasted against the FNV hash of the string. * * numbers are not changed at this time, only letters. */ @@ -137,20 +143,23 @@ do_host_cloak_host(const char *inbuf, char *outbuf) if (*tptr == '.') break; - if (isdigit(*tptr) || *tptr == '-') + if (isdigit((unsigned char)*tptr) || *tptr == '-') continue; - *tptr = b26_alphabet[(*tptr * accum) % 26]; + *tptr = b26_alphabet[(*tptr + accum) % 26]; + + /* Rotate one bit to avoid all digits being turned odd or even */ + accum = (accum << 1) | (accum >> 31); } /* pass 2: scramble each number in the address */ for (tptr = outbuf; *tptr != '\0'; tptr++) { - if (isdigit(*tptr)) - { - *tptr = 48 + ((*tptr * accum) % 10); - } - } + if (isdigit((unsigned char)*tptr)) + *tptr = '0' + (*tptr + accum) % 10; + + accum = (accum << 1) | (accum >> 31); + } } static void @@ -175,8 +184,7 @@ check_umode_change(void *vdata) } if (strcmp(source_p->host, source_p->localClient->mangledhost)) { - strlcpy(source_p->host, source_p->localClient->mangledhost, HOSTLEN); - distribute_hostchange(source_p); + distribute_hostchange(source_p, source_p->localClient->mangledhost); } 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", @@ -187,8 +195,7 @@ check_umode_change(void *vdata) if (source_p->localClient->mangledhost != NULL && !strcmp(source_p->host, source_p->localClient->mangledhost)) { - strlcpy(source_p->host, source_p->orighost, HOSTLEN); - distribute_hostchange(source_p); + distribute_hostchange(source_p, source_p->orighost); } } } @@ -203,7 +210,7 @@ check_new_user(void *vdata) source_p->umodes &= ~user_modes['h']; return; } - source_p->localClient->mangledhost = rb_malloc(HOSTLEN); + source_p->localClient->mangledhost = rb_malloc(HOSTLEN + 1); if (!irccmp(source_p->orighost, source_p->sockhost)) do_host_cloak_ip(source_p->orighost, source_p->localClient->mangledhost); else @@ -212,7 +219,7 @@ check_new_user(void *vdata) source_p->umodes &= ~user_modes['h']; if (source_p->umodes & user_modes['h']) { - strlcpy(source_p->host, source_p->localClient->mangledhost, sizeof(source_p->host)); + rb_strlcpy(source_p->host, source_p->localClient->mangledhost, sizeof(source_p->host)); if (irccmp(source_p->host, source_p->orighost)) SetDynSpoof(source_p); }