src/modules/extra/m_ziplink.cpp

   1 #include <string>
   2 #include <vector>
   3
   4 #include "zlib.h"
   5
   6 #include "inspircd_config.h"
   7 #include "configreader.h"
   8 #include "users.h"
   9 #include "channels.h"
  10 #include "modules.h"
  11
  12 #include "socket.h"
  13 #include "hashcomp.h"
  14 #include "inspircd.h"
  15
  16 #include "transport.h"
  17
  18 /* $ModDesc: Provides zlib link support for servers */
  19 /* $LinkerFlags: -lz */
  20 /* $ModDep: transport.h */
  21
  22 /*
  23  * Compressed data is transmitted across the link in the following format:
  24  *
  25  *   0   1   2   3   4 ... n
  26  * +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
  27  * |       n       |              Z0 -> Zn                         |
  28  * +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
  29  *
  30  * Where: n is the size of a frame, in network byte order, 4 bytes.
  31  * Z0 through Zn are Zlib compressed data, n bytes in length.
  32  *
  33  * If the module fails to read the entire frame, then it will buffer
  34  * the portion of the last frame it received, then attempt to read
  35  * the next part of the frame next time a write notification arrives.
  36  *
  37  * ZLIB_BEST_COMPRESSION (9) is used for all sending of data with
  38  * a flush after each frame. A frame may contain multiple lines
  39  * and should be treated as raw binary data.
  40  *
  41  */
  42
  43 static InspIRCd* SI;
  44
  45 enum izip_status { IZIP_OPEN, IZIP_CLOSED };
  46
  47 const unsigned int CHUNK = 16384;
  48
  49 class CountedBuffer : public classbase
  50 {
  51         int bufptr;            /* Current tail location */
  52         unsigned char* buffer; /* Current buffer contents */
  53         int bufsz;             /* Current buffer size */
  54         int amount_expected;   /* Amount of data expected */
  55         int amount_read;       /* Amount of data read so far */
  56  public:
  57         CountedBuffer()
  58         {
  59                 bufsz = 1024;
  60                 buffer = new unsigned char[bufsz + 1];
  61                 bufptr = 0;
  62                 amount_read = 0;
  63                 amount_expected = 0;
  64         }
  65
  66         ~CountedBuffer()
  67         {
  68                 delete[] buffer;
  69         }
  70
  71         void AddData(unsigned char* data, int data_length)
  72         {
  73                 SI->Log(DEBUG,"AddData, %d bytes to add", data_length);
  74                 if ((data_length + bufptr) > bufsz)
  75                 {
  76                         SI->Log(DEBUG,"Need to extend buffer to %d, is now %d", data_length + bufptr, bufsz);
  77                         /* Buffer is too small, enlarge it and copy contents */
  78                         int old_bufsz = bufsz;
  79                         unsigned char* temp = buffer;
  80
  81                         bufsz += data_length;
  82                         buffer = new unsigned char[bufsz + 1];
  83
  84                         memcpy(buffer, temp, old_bufsz);
  85
  86                         delete[] temp;
  87                 }
  88
  89                 SI->Log(DEBUG,"Copy data in at pos %d", bufptr);
  90
  91                 memcpy(buffer + bufptr, data, data_length);
  92                 bufptr += data_length;
  93                 amount_read += data_length;
  94
  95                 SI->Log(DEBUG,"Amount read is now %d, bufptr is now %d", amount_read, bufptr);
  96
  97                 if ((!amount_expected) && (amount_read >= 4))
  98                 {
  99                         SI->Log(DEBUG,"We dont yet have an expected amount");
 100                         /* We have enough to read an int */
 101                         int* size = (int*)buffer;
 102                         amount_expected = ntohl(*size);
 103                         SI->Log(DEBUG,"Expected amount is %d", amount_expected);
 104                 }
 105         }
 106
 107         int GetFrame(unsigned char* frame, int maxsize)
 108         {
 109                 if (amount_expected)
 110                 {
 111                         SI->Log(DEBUG,"Were expecting a frame of size %d", amount_expected);
 112                         /* We know how much we're expecting...
 113                          * Do we have enough yet?
 114                          */
 115                         if ((amount_read - 4) >= amount_expected)
 116                         {
 117                                 SI->Log(DEBUG,"We have enough for the frame (have %d)", (amount_read - 4));
 118                                 int amt_ex = amount_expected;
 119                                 /* Yes, we have enough now */
 120                                 memcpy(frame, buffer + 4, amount_expected > maxsize ? maxsize : amount_expected);
 121                                 RemoveFirstFrame();
 122                                 return (amt_ex > maxsize) ? maxsize : amt_ex;
 123                         }
 124                 }
 125                 /* Not enough for a frame yet, COME AGAIN! */
 126                 return 0;
 127         }
 128
 129         void RemoveFirstFrame()
 130         {
 131                 SI->Log(DEBUG,"Removing first frame from buffer sized %d", amount_expected);
 132                 unsigned char* temp = buffer;
 133
 134                 bufsz -= (amount_expected + 4);
 135                 buffer = new unsigned char[bufsz + 1];
 136
 137                 SI->Log(DEBUG,"Shrunk buffer to %d", bufsz);
 138
 139                 memcpy(buffer, temp + amount_expected + 4, bufsz);
 140
 141                 amount_read -= (amount_expected + 4);
 142                 SI->Log(DEBUG,"Amount read now %d", amount_read);
 143
 144                 if (amount_read >= 4)
 145                 {
 146                         /* We have enough to read an int */
 147                         int* size = (int*)buffer;
 148                         amount_expected = ntohl(*size);
 149                 }
 150                 else
 151                         amount_expected = 0;
 152
 153                 SI->Log(DEBUG,"Amount expected now %d", amount_expected);
 154
 155                 bufptr = 0;
 156
 157                 delete[] temp;
 158         }
 159 };
 160
 161 /** Represents an ZIP user's extra data
 162  */
 163 class izip_session : public classbase
 164 {
 165  public:
 166         z_stream c_stream; /* compression stream */
 167         z_stream d_stream; /* decompress stream */
 168         izip_status status;
 169         int fd;
 170         CountedBuffer* inbuf;
 171 };
 172
 173 class ModuleZLib : public Module
 174 {
 175         izip_session sessions[MAX_DESCRIPTORS];
 176         float total_out_compressed;
 177         float total_in_compressed;
 178         float total_out_uncompressed;
 179         float total_in_uncompressed;
 180
 181  public:
 182
 183         ModuleZLib(InspIRCd* Me)
 184                 : Module::Module(Me)
 185         {
 186                 ServerInstance->PublishInterface("InspSocketHook", this);
 187
 188                 total_out_compressed = total_in_compressed = 0;
 189                 total_out_uncompressed = total_out_uncompressed = 0;
 190
 191                 SI = ServerInstance;
 192         }
 193
 194         virtual ~ModuleZLib()
 195         {
 196         }
 197
 198         virtual Version GetVersion()
 199         {
 200                 return Version(1, 1, 0, 0, VF_VENDOR, API_VERSION);
 201         }
 202
 203         void Implements(char* List)
 204         {
 205                 List[I_OnRawSocketConnect] = List[I_OnRawSocketAccept] = List[I_OnRawSocketClose] = List[I_OnRawSocketRead] = List[I_OnRawSocketWrite] = 1;
 206                 List[I_OnStats] = List[I_OnRequest] = 1;
 207         }
 208
 209         virtual char* OnRequest(Request* request)
 210         {
 211                 ISHRequest* ISR = (ISHRequest*)request;
 212                 if (strcmp("IS_NAME", request->GetId()) == 0)
 213                 {
 214                         return "zip";
 215                 }
 216                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 217                 {
 218                         char* ret = "OK";
 219                         try
 220                         {
 221                                 ret = ServerInstance->Config->AddIOHook((Module*)this, (InspSocket*)ISR->Sock) ? (char*)"OK" : NULL;
 222                         }
 223                         catch (ModuleException& e)
 224                         {
 225                                 return NULL;
 226                         }
 227                         return ret;
 228                 }
 229                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 230                 {
 231                         return ServerInstance->Config->DelIOHook((InspSocket*)ISR->Sock) ? (char*)"OK" : NULL;
 232                 }
 233                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 234                 {
 235                         return "OK";
 236                 }
 237                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 238                 {
 239                         return NULL;
 240                 }
 241                 return NULL;
 242         }
 243
 244         virtual int OnStats(char symbol, userrec* user, string_list &results)
 245         {
 246                 if (symbol == 'z')
 247                 {
 248                         std::string sn = ServerInstance->Config->ServerName;
 249
 250                         float outbound_r = 100 - ((total_out_compressed / (total_out_uncompressed + 0.001)) * 100);
 251                         float inbound_r = 100 - ((total_in_compressed / (total_in_uncompressed + 0.001)) * 100);
 252
 253                         float total_compressed = total_in_compressed + total_out_compressed;
 254                         float total_uncompressed = total_in_uncompressed + total_out_uncompressed;
 255
 256                         float total_r = 100 - ((total_compressed / (total_uncompressed + 0.001)) * 100);
 257
 258                         char outbound_ratio[MAXBUF], inbound_ratio[MAXBUF], combined_ratio[MAXBUF];
 259
 260                         sprintf(outbound_ratio, "%3.2f%%", outbound_r);
 261                         sprintf(inbound_ratio, "%3.2f%%", inbound_r);
 262                         sprintf(combined_ratio, "%3.2f%%", total_r);
 263
 264                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_compressed   = "+ConvToStr(total_out_compressed));
 265                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_compressed    = "+ConvToStr(total_in_compressed));
 266                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_uncompressed = "+ConvToStr(total_out_uncompressed));
 267                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_uncompressed  = "+ConvToStr(total_in_uncompressed));
 268                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_ratio        = "+outbound_ratio);
 269                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_ratio         = "+inbound_ratio);
 270                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS combined_ratio        = "+combined_ratio);
 271                         return 0;
 272                 }
 273
 274                 return 0;
 275         }
 276
 277         virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
 278         {
 279                 izip_session* session = &sessions[fd];
 280
 281                 /* allocate deflate state */
 282                 session->fd = fd;
 283                 session->status = IZIP_OPEN;
 284
 285                 session->inbuf = new CountedBuffer();
 286                 ServerInstance->Log(DEBUG,"session->inbuf ALLOC = %d, %08x", fd, session->inbuf);
 287
 288                 session->c_stream.zalloc = (alloc_func)0;
 289                 session->c_stream.zfree = (free_func)0;
 290                 session->c_stream.opaque = (voidpf)0;
 291
 292                 session->d_stream.zalloc = (alloc_func)0;
 293                 session->d_stream.zfree = (free_func)0;
 294                 session->d_stream.opaque = (voidpf)0;
 295         }
 296
 297         virtual void OnRawSocketConnect(int fd)
 298         {
 299                 OnRawSocketAccept(fd, "", 0);
 300         }
 301
 302         virtual void OnRawSocketClose(int fd)
 303         {
 304                 CloseSession(&sessions[fd]);
 305         }
 306
 307         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 308         {
 309                 izip_session* session = &sessions[fd];
 310
 311                 if (session->status == IZIP_CLOSED)
 312                         return 1;
 313
 314                 unsigned char compr[CHUNK + 1];
 315                 unsigned int total_decomp = 0;
 316
 317                 readresult = read(fd, compr, CHUNK);
 318
 319                 if (readresult > 0)
 320                 {
 321                         session->inbuf->AddData(compr, readresult);
 322
 323                         int size = session->inbuf->GetFrame(compr, CHUNK);
 324                         while ((size) && (total_decomp < count))
 325                         {
 326
 327                                 session->d_stream.next_in  = (Bytef*)compr;
 328                                 session->d_stream.avail_in = 0;
 329                                 session->d_stream.next_out = (Bytef*)(buffer + total_decomp);
 330                                 if (inflateInit(&session->d_stream) != Z_OK)
 331                                         return -EBADF;
 332
 333                                 while ((session->d_stream.total_out < count) && (session->d_stream.total_in < (unsigned int)size))
 334                                 {
 335                                         session->d_stream.avail_in = session->d_stream.avail_out = 1;
 336                                         if (inflate(&session->d_stream, Z_NO_FLUSH) == Z_STREAM_END)
 337                                                 break;
 338                                 }
 339
 340                                 inflateEnd(&session->d_stream);
 341
 342                                 total_in_compressed += readresult;
 343                                 readresult = session->d_stream.total_out;
 344                                 total_in_uncompressed += session->d_stream.total_out;
 345
 346                                 total_decomp += session->d_stream.total_out;
 347
 348                                 ServerInstance->Log(DEBUG,"Decompressed %d bytes", session->d_stream.total_out);
 349
 350                                 size = session->inbuf->GetFrame(compr, CHUNK);
 351                         }
 352
 353                         buffer[total_decomp] = 0;
 354                 }
 355                 return (readresult > 0);
 356         }
 357
 358         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 359         {
 360                 ServerInstance->Log(DEBUG,"Compressing %d bytes", count);
 361
 362                 izip_session* session = &sessions[fd];
 363                 int ocount = count;
 364
 365                 if (!count)
 366                 {
 367                         ServerInstance->Log(DEBUG,"Nothing to do!");
 368                         return 1;
 369                 }
 370
 371                 if(session->status != IZIP_OPEN)
 372                 {
 373                         CloseSession(session);
 374                         return 0;
 375                 }
 376
 377                 unsigned char compr[count*2+4];
 378
 379                 if (deflateInit(&session->c_stream, Z_BEST_COMPRESSION) != Z_OK)
 380                 {
 381                         ServerInstance->Log(DEBUG,"Deflate init failed");
 382                 }
 383
 384                 session->c_stream.next_in  = (Bytef*)buffer;
 385                 session->c_stream.next_out = compr+4;
 386
 387                 while ((session->c_stream.total_in < (unsigned int)count) && (session->c_stream.total_out < (unsigned int)count*2))
 388                 {
 389                         session->c_stream.avail_in = session->c_stream.avail_out = 1; /* force small buffers */
 390                         if (deflate(&session->c_stream, Z_NO_FLUSH) != Z_OK)
 391                         {
 392                                 ServerInstance->Log(DEBUG,"Couldnt deflate!");
 393                                 CloseSession(session);
 394                                 return 0;
 395                         }
 396                 }
 397                 /* Finish the stream, still forcing small buffers: */
 398                 for (;;)
 399                 {
 400                         session->c_stream.avail_out = 1;
 401                         if (deflate(&session->c_stream, Z_FINISH) == Z_STREAM_END)
 402                                 break;
 403                 }
 404
 405                 deflateEnd(&session->c_stream);
 406
 407                 total_out_uncompressed += ocount;
 408                 total_out_compressed += session->c_stream.total_out;
 409
 410                 int x = htonl(session->c_stream.total_out);
 411                 /** XXX: We memcpy it onto the start of the buffer like this to save ourselves a write().
 412                  * A memcpy of 4 or so bytes is less expensive and gives the tcp stack more chance of
 413                  * assembling the frame size into the same packet as the compressed frame.
 414                  */
 415                 memcpy(compr, &x, sizeof(x));
 416                 write(fd, compr, session->c_stream.total_out+4);
 417
 418                 return ocount;
 419         }
 420
 421         void CloseSession(izip_session* session)
 422         {
 423                 if (session->status = IZIP_OPEN)
 424                 {
 425                         session->status = IZIP_CLOSED;
 426                         delete session->inbuf;
 427                 }
 428         }
 429
 430 };
 431
 432 class ModuleZLibFactory : public ModuleFactory
 433 {
 434  public:
 435         ModuleZLibFactory()
 436         {
 437         }
 438
 439         ~ModuleZLibFactory()
 440         {
 441         }
 442
 443         virtual Module * CreateModule(InspIRCd* Me)
 444         {
 445                 return new ModuleZLib(Me);
 446         }
 447 };
 448
 449
 450 extern "C" void * init_module( void )
 451 {
 452         return new ModuleZLibFactory;
 453 }