-/* $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"
#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)
{ 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
{
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.
*/
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
}
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",
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);
}
}
}
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
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);
}
projects / solanum.git / blobdiff