X-Git-Url: https://jfr.im/git/irc/rqf/shadowircd.git/blobdiff_plain/2b2e97af7fdb9b456ab168f25a23208b428e4131..60b3d9e512cf396eb2b71de9ba48fec166a175c9:/extensions/ip_cloaking.c

diff --git a/extensions/ip_cloaking.c b/extensions/ip_cloaking.c
index 1b5af63..035913e 100644
--- a/extensions/ip_cloaking.c
+++ b/extensions/ip_cloaking.c
@@ -6,6 +6,7 @@
 #include "client.h"
 #include "ircd.h"
 #include "send.h"
+#include "hash.h"
 #include "s_conf.h"
 #include "s_user.h"
 #include "s_serv.h"
@@ -59,63 +60,61 @@ distribute_hostchange(struct Client *client)
 	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 */
-
-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)
 {
+	/* 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;
+		}
 
-	snprintf(outbuf, HOSTLEN, "%s.%x", buf, accum);
+		if (ipv6 && sepcount < totalcount / 2)
+			continue;
+
+		if (!ipv6 && sepcount < 2)
+			continue;
+
+		*tptr = chartable[(*tptr + accum) % 20];
+		accum = (accum << 1) | (accum >> 31);
+	}
 }
 
 static void
@@ -123,12 +122,12 @@ 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.
+	 * alphabet toasted against the FNV hash of the string.
 	 *
 	 * numbers are not changed at this time, only letters.
 	 */
@@ -140,16 +139,19 @@ do_host_cloak_host(const char *inbuf, char *outbuf)
 		if (isdigit(*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);
-		}
+			*tptr = '0' + (*tptr + accum) % 10;
+
+		accum = (accum << 1) | (accum >> 31);
 	}	
 }
 
@@ -175,7 +177,7 @@ check_umode_change(void *vdata)
 		}
 		if (strcmp(source_p->host, source_p->localClient->mangledhost))
 		{
-			strlcpy(source_p->host, source_p->localClient->mangledhost, HOSTLEN);
+			rb_strlcpy(source_p->host, source_p->localClient->mangledhost, HOSTLEN + 1);
 			distribute_hostchange(source_p);
 		}
 		else /* not really nice, but we need to send this numeric here */
@@ -187,7 +189,7 @@ 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);
+			rb_strlcpy(source_p->host, source_p->orighost, HOSTLEN + 1);
 			distribute_hostchange(source_p);
 		}
 	}
@@ -203,7 +205,7 @@ 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 +214,7 @@ 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);
 	}