Add ip_cloaking_4.0 module, which is the same cloaking as 3.2, but moves the usermode from +h to +x,

which allows us to start transitioning this usermode change.

extensions/Makefile.in

@@ -47,6 +47,8 @@ SRCS =                          \
   hurt.c			\
   ip_cloaking.c			\
   ip_cloaking_old.c		\
+  ip_cloaking_3.0.c		\
+  ip_cloaking_4.0.c		\
   sno_farconnect.c		\
   sno_globalkline.c		\
   sno_globaloper.c		\

extensions/ip_cloaking_4.0.c

@@ -0,0 +1,221 @@
+/* $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 "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 int
+_modinit(void)
+{
+	/* add the usermode to the available slot */
+	user_modes['x'] = find_umode_slot();
+	construct_umodebuf();
+
+	return 0;
+}
+
+static void
+_moddeinit(void)
+{
+	/* disable the umode and remove it from the available list */
+	user_modes['x'] = 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);
+}
+
+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;
+	uint32_t accum = fnv_hash((const unsigned char*) inbuf, 32);
+	int sepcount = 0;
+	int totalcount = 0;
+	int ipv6 = 0;
+
+	rb_strlcpy(outbuf, inbuf, HOSTLEN + 1);
+
+	if (strchr(outbuf, ':'))
+	{
+		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;
+
+	for (tptr = outbuf; *tptr != '\0'; tptr++) 
+	{
+		if (*tptr == ':' || *tptr == '.')
+		{
+			sepcount++;
+			continue;
+		}
+
+		if (ipv6 && sepcount < totalcount / 2)
+			continue;
+
+		if (!ipv6 && sepcount < 2)
+			continue;
+
+		*tptr = chartable[(*tptr + accum) % 20];
+		accum = (accum << 1) | (accum >> 31);
+	}
+}
+
+static void
+do_host_cloak_host(const char *inbuf, char *outbuf)
+{
+	char b26_alphabet[] = "abcdefghijklmnopqrstuvwxyz";
+	char *tptr;
+	uint32_t accum = fnv_hash((const unsigned char*) inbuf, 32);
+
+	rb_strlcpy(outbuf, inbuf, HOSTLEN + 1);
+
+	/* 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.
+	 */
+	for (tptr = outbuf; *tptr != '\0'; tptr++)
+	{
+		if (*tptr == '.')
+			break;
+
+		if (isdigit(*tptr) || *tptr == '-')
+			continue;
+
+		*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 = '0' + (*tptr + accum) % 10;
+
+		accum = (accum << 1) | (accum >> 31);
+	}	
+}
+
+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['x']))
+		return;
+
+	if (source_p->umodes & user_modes['x'])
+	{
+		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['x'];
+			return;
+		}
+		if (strcmp(source_p->host, source_p->localClient->mangledhost))
+		{
+			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 */
+			sendto_one_numeric(source_p, RPL_HOSTHIDDEN, "%s :is now your hidden host",
+				source_p->host);
+	}
+	else if (!(source_p->umodes & user_modes['x']))
+	{
+		if (source_p->localClient->mangledhost != NULL &&
+				!strcmp(source_p->host, source_p->localClient->mangledhost))
+		{
+			rb_strlcpy(source_p->host, source_p->orighost, HOSTLEN + 1);
+			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['x'];
+		return;
+	}
+	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
+		do_host_cloak_host(source_p->orighost, source_p->localClient->mangledhost);
+	if (IsDynSpoof(source_p))
+		source_p->umodes &= ~user_modes['x'];
+	if (source_p->umodes & user_modes['x'])
+	{
+		rb_strlcpy(source_p->host, source_p->localClient->mangledhost, sizeof(source_p->host));
+		if (irccmp(source_p->host, source_p->orighost))
+			SetDynSpoof(source_p);
+	}
+}