-#include <stdio.h>
+/* +------------------------------------+
+ * | Inspire Internet Relay Chat Daemon |
+ * +------------------------------------+
+ *
+ * Inspire is copyright (C) 2002-2004 ChatSpike-Dev.
+ * E-mail:
+ * <brain@chatspike.net>
+ * <Craig@chatspike.net>
+ *
+ * Written by Craig Edwards, Craig McLure, and others.
+ * This program is free but copyrighted software; see
+ * the file COPYING for details.
+ *
+ * ---------------------------------------------------
+ */
+
+// Hostname cloaking (+x mode) module for inspircd.
+// version 1.0.0.1 by brain (C. J. Edwards) Mar 2004.
+//
+// When loaded this module will automatically set the
+// +x mode on all connecting clients.
+//
+// Setting +x on a client causes the module to change the
+// dhost entry (displayed host) for each user who has the
+// mode, cloaking their host. Unlike unreal, the algorithm
+// is non-reversible as uncloaked hosts are passed along
+// the server->server link, and all encoding of hosts is
+// done locally on the server by this module.
+#include <stdio.h>
#include "users.h"
#include "channels.h"
#include "modules.h"
/* $ModDesc: Provides masking of user hostnames */
+
+/* The four core functions - F1 is optimized somewhat */
+
+#define F1(x, y, z) (z ^ (x & (y ^ z)))
+#define F2(x, y, z) F1(z, x, y)
+#define F3(x, y, z) (x ^ y ^ z)
+#define F4(x, y, z) (y ^ (x | ~z))
+#define MD5STEP(f,w,x,y,z,in,s) (w += f(x,y,z) + in, w = (w<<s | w>>(32-s)) + x)
+
+typedef unsigned long word32;
+typedef unsigned char byte;
+
+struct xMD5Context {
+ word32 buf[4];
+ word32 bytes[2];
+ word32 in[16];
+};
+
class ModuleCloaking : public Module
{
private:
Server *Srv;
+
+ void byteSwap(word32 *buf, unsigned words)
+ {
+ byte *p = (byte *)buf;
+
+ do {
+ *buf++ = (word32)((unsigned)p[3] << 8 | p[2]) << 16 |
+ ((unsigned)p[1] << 8 | p[0]);
+ p += 4;
+ } while (--words);
+ }
+
+ void xMD5Init(struct xMD5Context *ctx)
+ {
+ ctx->buf[0] = 0x67452301;
+ ctx->buf[1] = 0xefcdab89;
+ ctx->buf[2] = 0x98badcfe;
+ ctx->buf[3] = 0x10325476;
+
+ ctx->bytes[0] = 0;
+ ctx->bytes[1] = 0;
+ }
+
+ void xMD5Update(struct xMD5Context *ctx, byte const *buf, int len)
+ {
+ word32 t;
+
+ /* Update byte count */
+
+ t = ctx->bytes[0];
+ if ((ctx->bytes[0] = t + len) < t)
+ ctx->bytes[1]++; /* Carry from low to high */
+
+ t = 64 - (t & 0x3f); /* Space available in ctx->in (at least 1) */
+ if ((unsigned)t > (unsigned)len) {
+ memcpy((byte *)ctx->in + 64 - (unsigned)t, buf, len);
+ return;
+ }
+ /* First chunk is an odd size */
+ memcpy((byte *)ctx->in + 64 - (unsigned)t, buf, (unsigned)t);
+ byteSwap(ctx->in, 16);
+ xMD5Transform(ctx->buf, ctx->in);
+ buf += (unsigned)t;
+ len -= (unsigned)t;
+
+ /* Process data in 64-byte chunks */
+ while (len >= 64) {
+ memcpy(ctx->in, buf, 64);
+ byteSwap(ctx->in, 16);
+ xMD5Transform(ctx->buf, ctx->in);
+ buf += 64;
+ len -= 64;
+ }
+
+ /* Handle any remaining bytes of data. */
+ memcpy(ctx->in, buf, len);
+ }
+
+ void xMD5Final(byte digest[16], struct xMD5Context *ctx)
+ {
+ int count = (int)(ctx->bytes[0] & 0x3f); /* Bytes in ctx->in */
+ byte *p = (byte *)ctx->in + count; /* First unused byte */
+
+ /* Set the first char of padding to 0x80. There is always room. */
+ *p++ = 0x80;
+
+ /* Bytes of padding needed to make 56 bytes (-8..55) */
+ count = 56 - 1 - count;
+
+ if (count < 0) { /* Padding forces an extra block */
+ memset(p, 0, count+8);
+ byteSwap(ctx->in, 16);
+ xMD5Transform(ctx->buf, ctx->in);
+ p = (byte *)ctx->in;
+ count = 56;
+ }
+ memset(p, 0, count+8);
+ byteSwap(ctx->in, 14);
+
+ /* Append length in bits and transform */
+ ctx->in[14] = ctx->bytes[0] << 3;
+ ctx->in[15] = ctx->bytes[1] << 3 | ctx->bytes[0] >> 29;
+ xMD5Transform(ctx->buf, ctx->in);
+
+ byteSwap(ctx->buf, 4);
+ memcpy(digest, ctx->buf, 16);
+ memset(ctx, 0, sizeof(ctx));
+ }
+
+ void xMD5Transform(word32 buf[4], word32 const in[16])
+ {
+ register word32 a, b, c, d;
+
+ a = buf[0];
+ b = buf[1];
+ c = buf[2];
+ d = buf[3];
+
+ MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
+ MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
+ MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
+ MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
+ MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
+ MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
+ MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
+ MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
+ MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
+ MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
+ MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
+ MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
+ MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
+ MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
+ MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
+ MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
+
+ MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
+ MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
+ MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
+ MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
+ MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
+ MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
+ MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
+ MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
+ MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
+ MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
+ MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
+ MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
+ MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
+ MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
+ MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
+ MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
+
+ MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
+ MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
+ MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
+ MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
+ MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
+ MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
+ MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
+ MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
+ MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
+ MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
+ MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
+ MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
+ MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
+ MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
+ MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
+ MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
+
+ MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
+ MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
+ MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
+ MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
+ MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
+ MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
+ MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
+ MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
+ MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
+ MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
+ MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
+ MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
+ MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
+ MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
+ MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
+ MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
+
+ buf[0] += a;
+ buf[1] += b;
+ buf[2] += c;
+ buf[3] += d;
+ }
+
+
+ void MyMD5(void *dest, void *orig, int len)
+ {
+ struct xMD5Context context;
+
+ xMD5Init(&context);
+ xMD5Update(&context, (const unsigned char*)orig, len);
+ xMD5Final((unsigned char*)dest, &context);
+ }
+
+
+ void GenHash(char* src, char* dest)
+ {
+ // purposefully lossy md5 - only gives them the most significant 4 bits
+ // of every md5 output byte.
+ int i = 0;
+ unsigned char bytes[16];
+ char hash[MAXBUF];
+ strcpy(hash,"");
+ MyMD5((char*)bytes,src,strlen(src));
+ for (i = 0; i < 16; i++)
+ {
+ const char* xtab = "F92E45D871BCA630";
+ unsigned char hi = xtab[bytes[i] / 16];
+ char hx[2];
+ hx[0] = hi;
+ hx[1] = '\0';
+ strlcat(hash,hx,MAXBUF);
+ }
+ strlcpy(dest,hash,MAXBUF);
+ }
public:
ModuleCloaking()
{
+ // We must create an instance of the Server class to work with
Srv = new Server;
+
+ // we must create a new mode. Set the parameters so the
+ // mode doesn't require oper, and is a client usermode
+ // with no parameters (actually, you cant have params for a umode!)
+ if (!Srv->AddExtendedMode('x',MT_CLIENT,false,0,0))
+ {
+ // we couldn't claim mode x... possibly anther module has it,
+ // this might become likely to happen if there are a lot of 3rd
+ // party modules around in the future -- any 3rd party modules
+ // SHOULD implement a system of configurable mode letters (e.g.
+ // from a config file)
+ Srv->Log(DEFAULT,"*** m_cloaking: ERROR, failed to allocate user mode +x!");
+ printf("Could not claim usermode +x for this module!");
+ return;
+ }
}
virtual ~ModuleCloaking()
{
+ // not really neccessary, but free it anyway
delete Srv;
}
virtual Version GetVersion()
{
- return Version(1,0,0,0);
+ // returns the version number of the module to be
+ // listed in /MODULES
+ return Version(1,0,0,1,VF_STATIC|VF_VENDOR);
}
- virtual void OnUserConnect(userrec* user)
+ virtual int OnExtendedMode(userrec* user, void* target, char modechar, int type, bool mode_on, string_list ¶ms)
{
- if (strstr(user->dhost,"."))
+ // this method is called for any extended mode character.
+ // all module modes for all modules pass through here
+ // (unless another module further up the chain claims them)
+ // so we must be VERY careful to only act upon modes which
+ // we have claimed ourselves. This is a feature to allow
+ // modules to 'spy' on extended mode activity if they so wish.
+ if ((modechar == 'x') && (type == MT_CLIENT))
+ {
+ // OnExtendedMode gives us a void* as the target, we must cast
+ // it into a userrec* or a chanrec* depending on the value of
+ // the 'type' parameter (MT_CLIENT or MT_CHANNEL)
+ userrec* dest = (userrec*)target;
+
+ // we've now determined that this is our mode character...
+ // is the user adding the mode to their list or removing it?
+ if (mode_on)
+ {
+ // the mode is being turned on - so attempt to
+ // allocate the user a cloaked host using a non-reversible
+ // algorithm (its simple, but its non-reversible so the
+ // simplicity doesnt really matter). This algorithm
+ // will not work if the user has only one level of domain
+ // naming in their hostname (e.g. if they are on a lan or
+ // are connecting via localhost) -- this doesnt matter much.
+ if (strchr(dest->host,'.'))
+ {
+ // in inspircd users have two hostnames. A displayed
+ // hostname which can be modified by modules (e.g.
+ // to create vhosts, implement chghost, etc) and a
+ // 'real' hostname which you shouldnt write to.
+ std::string a = strstr(dest->host,".");
+ char ra[64];
+ this->GenHash(dest->host,ra);
+ std::string b = "";
+ in_addr testaddr;
+ if (!inet_aton(dest->host,&testaddr))
+ {
+ // if they have a hostname, make something appropriate
+ b = Srv->GetNetworkName() + "-" + std::string(ra) + a;
+ }
+ else
+ {
+ // else, they have an ip
+ b = std::string(ra) + "." + Srv->GetNetworkName() + ".cloak";
+ }
+ Srv->Log(DEBUG,"cloak: allocated "+b);
+ Srv->ChangeHost(dest,b);
+ }
+ }
+ else
+ {
+ // user is removing the mode, so just restore their real host
+ // and make it match the displayed one.
+ Srv->ChangeHost(dest,dest->host);
+ }
+ // this mode IS ours, and we have handled it. If we chose not to handle it,
+ // for example the user cannot cloak as they have a vhost or such, then
+ // we could return 0 here instead of 1 and the core would not send the mode
+ // change to the user.
+ return 1;
+ }
+ else
{
- std::string a = strstr(user->dhost,".");
- char ra[64];
- long seed,s2;
- memcpy(&seed,user->dhost,sizeof(long));
- memcpy(&s2,a.c_str(),sizeof(long));
- sprintf(ra,"%.8X",seed*s2*strlen(user->host));
- std::string b = Srv->GetNetworkName() + "-" + ra + a;
- Srv->Log(DEBUG,"cloak: allocated "+b);
- strcpy(user->dhost,b.c_str());
+ // this mode isn't ours, we have to bail and return 0 to not handle it.
+ return 0;
}
}
+ virtual void OnUserConnect(userrec* user)
+ {
+ // Heres the weird bit. When a user connects we must set +x on them, so
+ // we're going to use the SendMode method of the Server class to send
+ // the mode to the client. This is basically the same as sending an
+ // SAMODE in unreal. Note that to the user it will appear as if they set
+ // the mode on themselves.
+
+ char* modes[2]; // only two parameters
+ modes[0] = user->nick; // first parameter is the nick
+ modes[1] = "+x"; // second parameter is the mode
+ Srv->SendMode(modes,2,user); // send these, forming the command "MODE <nick> +x"
+ }
+
};
+// stuff down here is the module-factory stuff. For basic modules you can ignore this.
class ModuleCloakingFactory : public ModuleFactory
{