1 /* +------------------------------------+
2 * | Inspire Internet Relay Chat Daemon |
3 * +------------------------------------+
5 * InspIRCd is copyright (C) 2002-2006 ChatSpike-Dev.
7 * <brain@chatspike.net>
8 * <Craig@chatspike.net>
10 * Written by Craig Edwards, Craig McLure, and others.
11 * This program is free but copyrighted software; see
12 * the file COPYING for details.
14 * ---------------------------------------------------
17 #include "inspircd_config.h"
21 #include "configreader.h"
27 /* $ModDesc: Provides masking of user hostnames */
29 /* The four core functions - F1 is optimized somewhat */
31 #define F1(x, y, z) (z ^ (x & (y ^ z)))
32 #define F2(x, y, z) F1(z, x, y)
33 #define F3(x, y, z) (x ^ y ^ z)
34 #define F4(x, y, z) (y ^ (x | ~z))
35 #define MD5STEP(f,w,x,y,z,in,s) (w += f(x,y,z) + in, w = (w<<s | w>>(32-s)) + x)
38 typedef unsigned int uint32_t;
41 typedef uint32_t word32; /* NOT unsigned long. We don't support 16 bit platforms, anyway. */
42 typedef unsigned char byte;
44 /** An MD5 context, used by m_cloaking
46 class xMD5Context : public classbase
54 /** Handles user mode +x
56 class CloakUser : public ModeHandler
65 void byteSwap(word32 *buf, unsigned words)
67 byte *p = (byte *)buf;
71 *buf++ = (word32)((unsigned)p[3] << 8 | p[2]) << 16 |
72 ((unsigned)p[1] << 8 | p[0]);
77 void xMD5Init(struct xMD5Context *ctx)
88 void xMD5Update(struct xMD5Context *ctx, byte const *buf, int len)
92 /* Update byte count */
95 if ((ctx->bytes[0] = t + len) < t)
96 ctx->bytes[1]++; /* Carry from low to high */
98 t = 64 - (t & 0x3f); /* Space available in ctx->in (at least 1) */
99 if ((unsigned)t > (unsigned)len)
101 memcpy((byte *)ctx->in + 64 - (unsigned)t, buf, len);
104 /* First chunk is an odd size */
105 memcpy((byte *)ctx->in + 64 - (unsigned)t, buf, (unsigned)t);
106 byteSwap(ctx->in, 16);
107 xMD5Transform(ctx->buf, ctx->in);
111 /* Process data in 64-byte chunks */
114 memcpy(ctx->in, buf, 64);
115 byteSwap(ctx->in, 16);
116 xMD5Transform(ctx->buf, ctx->in);
121 /* Handle any remaining bytes of data. */
122 memcpy(ctx->in, buf, len);
125 void xMD5Final(byte digest[16], struct xMD5Context *ctx)
127 int count = (int)(ctx->bytes[0] & 0x3f); /* Bytes in ctx->in */
128 byte *p = (byte *)ctx->in + count; /* First unused byte */
130 /* Set the first char of padding to 0x80. There is always room. */
133 /* Bytes of padding needed to make 56 bytes (-8..55) */
134 count = 56 - 1 - count;
137 { /* Padding forces an extra block */
138 memset(p, 0, count+8);
139 byteSwap(ctx->in, 16);
140 xMD5Transform(ctx->buf, ctx->in);
144 memset(p, 0, count+8);
145 byteSwap(ctx->in, 14);
147 /* Append length in bits and transform */
148 ctx->in[14] = ctx->bytes[0] << 3;
149 ctx->in[15] = ctx->bytes[1] << 3 | ctx->bytes[0] >> 29;
150 xMD5Transform(ctx->buf, ctx->in);
152 byteSwap(ctx->buf, 4);
153 memcpy(digest, ctx->buf, 16);
154 memset(ctx, 0, sizeof(ctx));
157 void xMD5Transform(word32 buf[4], word32 const in[16])
159 register word32 a, b, c, d;
166 MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
167 MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
168 MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
169 MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
170 MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
171 MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
172 MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
173 MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
174 MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
175 MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
176 MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
177 MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
178 MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
179 MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
180 MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
181 MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
183 MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
184 MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
185 MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
186 MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
187 MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
188 MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
189 MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
190 MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
191 MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
192 MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
193 MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
194 MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
195 MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
196 MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
197 MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
198 MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
200 MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
201 MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
202 MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
203 MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
204 MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
205 MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
206 MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
207 MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
208 MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
209 MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
210 MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
211 MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
212 MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
213 MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
214 MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
215 MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
217 MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
218 MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
219 MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
220 MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
221 MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
222 MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
223 MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
224 MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
225 MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
226 MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
227 MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
228 MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
229 MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
230 MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
231 MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
232 MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
241 void MyMD5(void *dest, const void *orig, int len)
243 struct xMD5Context context;
246 xMD5Update(&context, (const unsigned char*)orig, len);
247 xMD5Final((unsigned char*)dest, &context);
251 void GenHash(const char* src, char* dest, int xtable = 0)
253 // purposefully lossy md5 - only gives them the most significant 4 bits
254 // of every md5 output byte.
256 unsigned char bytes[16];
259 MyMD5(bytes, src, strlen(src));
260 for (i = 0; i < 16; i++)
262 const char* xtab[] = {"F92E45D871BCA630", "A1B9D80C72E653F4", "1ABC078934DEF562", "ABCDEF5678901234"};
263 char hx[2] = { xtab[xtable][bytes[i] / 16], 0};
264 strlcat(hash,hx,MAXBUF);
266 strlcpy(dest,hash,MAXBUF);
270 CloakUser(InspIRCd* Instance) : ModeHandler(Instance, 'x', 0, 0, false, MODETYPE_USER, false) { }
272 ModeAction OnModeChange(userrec* source, userrec* dest, chanrec* channel, std::string ¶meter, bool adding)
274 /* Only opers can change other users modes */
275 if ((source != dest) && (!*source->oper))
276 return MODEACTION_DENY;
278 /* For remote clients, we dont take any action, we just allow it.
279 * The local server where they are will set their cloak instead.
282 return MODEACTION_ALLOW;
286 if(!dest->IsModeSet('x'))
288 /* The mode is being turned on - so attempt to
289 * allocate the user a cloaked host using a non-reversible
290 * algorithm (its simple, but its non-reversible so the
291 * simplicity doesnt really matter). This algorithm
292 * will not work if the user has only one level of domain
293 * naming in their hostname (e.g. if they are on a lan or
294 * are connecting via localhost) -- this doesnt matter much.
297 if (strchr(dest->host,'.') || strchr(dest->host,':'))
299 /* InspIRCd users have two hostnames; A displayed
300 * hostname which can be modified by modules (e.g.
301 * to create vhosts, implement chghost, etc) and a
302 * 'real' hostname which you shouldnt write to.
305 char* n = strstr(dest->host,".");
307 n = strstr(dest->host,":");
312 this->GenHash(dest->host,ra);
314 insp_inaddr testaddr;
315 std::string hostcloak = prefix + "-" + ra + a;
317 /* Fix by brain - if the cloaked host is > the max length of a host (64 bytes
318 * according to the DNS RFC) then tough titty, they get cloaked as an IP.
319 * Their ISP shouldnt go to town on subdomains, or they shouldnt have a kiddie
323 if ((insp_aton(dest->host,&testaddr) < 1) && (hostcloak.length() <= 64))
325 // if they have a hostname, make something appropriate
330 if (b.find(':') == std::string::npos)
333 irc::sepstream seps(dest->host, '.');
334 char ra1[64], ra2[64], ra3[64], ra4[64];
336 std::string octet1 = seps.GetToken();
337 std::string octet2 = seps.GetToken();
338 std::string octet3 = seps.GetToken();
339 std::string octet4 = seps.GetToken();
340 i1 = atoi(octet1.c_str());
341 i2 = atoi(octet2.c_str());
342 i3 = atoi(octet3.c_str());
343 i4 = atoi(octet4.c_str());
344 octet1.append(".").append(octet2).append(".").append(octet3);
345 octet2.append(".").append(octet3);
346 ServerInstance->Log(DEBUG,"oct1=%s, oct2=%s, oct3=%s, oct4=%s", octet1.c_str(), octet2.c_str(), octet3.c_str(), octet4.c_str());
347 this->GenHash(octet1.c_str(),ra1, (key1+i1) % 4);
348 this->GenHash(octet2.c_str(),ra2, (key2+i2) % 4);
349 this->GenHash(octet3.c_str(),ra3, (key3+i3) % 4);
350 this->GenHash(octet4.c_str(),ra4, (key4+i4) % 4);
351 ServerInstance->Log(DEBUG,"ra1=%s, ra2=%s, ra3=%s, ra4=%s", ra1, ra2, ra3, ra4);
352 /* This is safe as we know the length generated by our genhash is always 16 */
353 ra1[8] = ra2[8] = ra3[8] = ra4[8] = 0;
354 b.append(ra1).append(".").append(ra2).append(".").append(ra3).append(".").append(ra4);
359 b.append(ra).append(".").append(prefix).append(".cloak");
363 ServerInstance->Log(DEBUG,"cloak: allocated "+b);
364 dest->ChangeDisplayedHost(b.c_str());
367 dest->SetMode('x',true);
368 return MODEACTION_ALLOW;
373 if (dest->IsModeSet('x'))
375 /* User is removing the mode, so just restore their real host
376 * and make it match the displayed one.
378 dest->ChangeDisplayedHost(dest->host);
379 dest->SetMode('x',false);
380 return MODEACTION_ALLOW;
384 return MODEACTION_DENY;
389 ConfigReader Conf(ServerInstance);
390 key1 = key2 = key3 = key4 = 0;
391 key1 = Conf.ReadInteger("cloak","key1",0,false);
392 key2 = Conf.ReadInteger("cloak","key2",0,false);
393 key3 = Conf.ReadInteger("cloak","key3",0,false);
394 key4 = Conf.ReadInteger("cloak","key4",0,false);
396 prefix = Conf.ReadValue("cloak","prefix",0);
399 prefix = ServerInstance->Config->Network;
401 if (!key1 && !key2 && !key3 && !key4)
403 ModuleException ex("You have not defined cloak keys for m_cloaking!!! THIS IS INSECURE AND SHOULD BE CHECKED!");
410 class ModuleCloaking : public Module
417 ModuleCloaking(InspIRCd* Me)
420 /* Create new mode handler object */
421 cu = new CloakUser(ServerInstance);
423 /* Register it with the core */
424 ServerInstance->AddMode(cu, 'x');
429 virtual ~ModuleCloaking()
431 ServerInstance->Modes->DelMode(cu);
435 virtual Version GetVersion()
437 // returns the version number of the module to be
438 // listed in /MODULES
439 return Version(1,1,0,2,VF_COMMON|VF_VENDOR,API_VERSION);
442 virtual void OnRehash(const std::string ¶meter)
447 void Implements(char* List)
449 List[I_OnRehash] = 1;
453 // stuff down here is the module-factory stuff. For basic modules you can ignore this.
455 class ModuleCloakingFactory : public ModuleFactory
458 ModuleCloakingFactory()
462 ~ModuleCloakingFactory()
466 virtual Module * CreateModule(InspIRCd* Me)
468 return new ModuleCloaking(Me);
474 extern "C" void * init_module( void )
476 return new ModuleCloakingFactory;