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
  44 enum izip_status { IZIP_OPEN, IZIP_CLOSED };
  45
  46 const unsigned int CHUNK = 16384;
  47
  48 class CountedBuffer : public classbase
  49 {
  50         int bufptr;            /* Current tail location */
  51         unsigned char* buffer; /* Current buffer contents */
  52         int bufsz;             /* Current buffer size */
  53         int amount_expected;   /* Amount of data expected */
  54         int amount_read;       /* Amount of data read so far */
  55  public:
  56         CountedBuffer()
  57         {
  58                 bufsz = 1024;
  59                 buffer = new unsigned char[bufsz + 1];
  60                 bufptr = 0;
  61                 amount_read = 0;
  62         }
  63
  64         ~CountedBuffer()
  65         {
  66                 delete[] buffer;
  67         }
  68
  69         void AddData(unsigned char* data, int data_length)
  70         {
  71                 if ((data_length + bufptr) > bufsz)
  72                 {
  73                         /* Buffer is too small, enlarge it and copy contents */
  74                         int old_bufsz = bufsz;
  75                         unsigned char* temp = buffer;
  76
  77                         bufsz += data_length;
  78                         buffer = new unsigned char[bufsz + 1];
  79
  80                         memcpy(buffer, temp, old_bufsz);
  81
  82                         delete[] temp;
  83                 }
  84
  85                 memcpy(buffer + bufptr, data, data_length);
  86                 bufptr += data_length;
  87                 amount_read += data_length;
  88
  89                 if ((!amount_expected) && (amount_read >= 4))
  90                 {
  91                         /* We have enough to read an int */
  92                         int* size = (int*)buffer;
  93                         amount_expected = ntohl(*size);
  94                 }
  95         }
  96
  97         int GetFrame(unsigned char* frame, int maxsize)
  98         {
  99                 if (amount_expected)
 100                 {
 101                         /* We know how much we're expecting...
 102                          * Do we have enough yet?
 103                          */
 104                         if ((amount_read - 4) >= amount_expected)
 105                         {
 106                                 int amt_ex = amount_expected;
 107                                 /* Yes, we have enough now */
 108                                 memcpy(frame, buffer + 4, amount_expected > maxsize ? maxsize : amount_expected);
 109                                 RemoveFirstFrame();
 110                                 return (amt_ex > maxsize) ? maxsize : amt_ex;
 111                         }
 112                 }
 113                 /* Not enough for a frame yet, COME AGAIN! */
 114                 return 0;
 115         }
 116
 117         void RemoveFirstFrame()
 118         {
 119                 unsigned char* temp = buffer;
 120
 121                 bufsz -= (amount_expected + 4);
 122                 buffer = new unsigned char[bufsz + 1];
 123
 124                 memcpy(buffer, temp + amount_expected, bufsz);
 125
 126                 amount_read -= (amount_expected + 4);
 127
 128                 if (amount_read >= 4)
 129                 {
 130                         /* We have enough to read an int */
 131                         int* size = (int*)buffer;
 132                         amount_expected = ntohl(*size);
 133                 }
 134                 else
 135                         amount_expected = 0;
 136
 137                 bufptr = 0;
 138
 139                 delete[] temp;
 140         }
 141 };
 142
 143 /** Represents an ZIP user's extra data
 144  */
 145 class izip_session : public classbase
 146 {
 147  public:
 148         z_stream c_stream; /* compression stream */
 149         z_stream d_stream; /* decompress stream */
 150         izip_status status;
 151         int need_bytes;
 152         int fd;
 153         CountedBuffer* inbuf;
 154 };
 155
 156 class ModuleZLib : public Module
 157 {
 158         izip_session sessions[MAX_DESCRIPTORS];
 159         float total_out_compressed;
 160         float total_in_compressed;
 161         float total_out_uncompressed;
 162         float total_in_uncompressed;
 163
 164  public:
 165
 166         ModuleZLib(InspIRCd* Me)
 167                 : Module::Module(Me)
 168         {
 169                 ServerInstance->PublishInterface("InspSocketHook", this);
 170
 171                 total_out_compressed = total_in_compressed = 0;
 172                 total_out_uncompressed = total_out_uncompressed = 0;
 173         }
 174
 175         virtual ~ModuleZLib()
 176         {
 177         }
 178
 179         virtual Version GetVersion()
 180         {
 181                 return Version(1, 1, 0, 0, VF_VENDOR, API_VERSION);
 182         }
 183
 184         void Implements(char* List)
 185         {
 186                 List[I_OnRawSocketConnect] = List[I_OnRawSocketAccept] = List[I_OnRawSocketClose] = List[I_OnRawSocketRead] = List[I_OnRawSocketWrite] = 1;
 187                 List[I_OnStats] = List[I_OnRequest] = 1;
 188         }
 189
 190         virtual char* OnRequest(Request* request)
 191         {
 192                 ISHRequest* ISR = (ISHRequest*)request;
 193                 if (strcmp("IS_NAME", request->GetId()) == 0)
 194                 {
 195                         return "zip";
 196                 }
 197                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 198                 {
 199                         return ServerInstance->Config->AddIOHook((Module*)this, (InspSocket*)ISR->Sock) ? (char*)"OK" : NULL;
 200                 }
 201                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 202                 {
 203                         return ServerInstance->Config->DelIOHook((InspSocket*)ISR->Sock) ? (char*)"OK" : NULL;
 204                 }
 205                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 206                 {
 207                         return "OK";
 208                 }
 209                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 210                 {
 211                         return NULL;
 212                 }
 213                 return NULL;
 214         }
 215
 216         virtual int OnStats(char symbol, userrec* user, string_list &results)
 217         {
 218                 if (symbol == 'z')
 219                 {
 220                         std::string sn = ServerInstance->Config->ServerName;
 221
 222                         float outbound_r = 100 - ((total_out_compressed / (total_out_uncompressed + 0.001)) * 100);
 223                         float inbound_r = 100 - ((total_in_compressed / (total_in_uncompressed + 0.001)) * 100);
 224
 225                         float total_compressed = total_in_compressed + total_out_compressed;
 226                         float total_uncompressed = total_in_uncompressed + total_out_uncompressed;
 227
 228                         float total_r = 100 - ((total_compressed / (total_uncompressed + 0.001)) * 100);
 229
 230                         char outbound_ratio[MAXBUF], inbound_ratio[MAXBUF], combined_ratio[MAXBUF];
 231
 232                         sprintf(outbound_ratio, "%3.2f%%", outbound_r);
 233                         sprintf(inbound_ratio, "%3.2f%%", inbound_r);
 234                         sprintf(combined_ratio, "%3.2f%%", total_r);
 235
 236                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_compressed   = "+ConvToStr(total_out_compressed));
 237                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_compressed    = "+ConvToStr(total_in_compressed));
 238                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_uncompressed = "+ConvToStr(total_out_uncompressed));
 239                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_uncompressed  = "+ConvToStr(total_in_uncompressed));
 240                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_ratio        = "+outbound_ratio);
 241                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_ratio         = "+inbound_ratio);
 242                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS combined_ratio        = "+combined_ratio);
 243                         return 0;
 244                 }
 245
 246                 return 0;
 247         }
 248
 249         virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
 250         {
 251                 izip_session* session = &sessions[fd];
 252
 253                 /* allocate deflate state */
 254                 session->fd = fd;
 255                 session->status = IZIP_OPEN;
 256
 257                 session->inbuf = new CountedBuffer();
 258
 259                 session->c_stream.zalloc = (alloc_func)0;
 260                 session->c_stream.zfree = (free_func)0;
 261                 session->c_stream.opaque = (voidpf)0;
 262
 263                 session->d_stream.zalloc = (alloc_func)0;
 264                 session->d_stream.zfree = (free_func)0;
 265                 session->d_stream.opaque = (voidpf)0;
 266
 267         }
 268
 269         virtual void OnRawSocketConnect(int fd)
 270         {
 271                 OnRawSocketAccept(fd, "", 0);
 272         }
 273
 274         virtual void OnRawSocketClose(int fd)
 275         {
 276                 CloseSession(&sessions[fd]);
 277         }
 278
 279         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 280         {
 281                 izip_session* session = &sessions[fd];
 282
 283                 if (session->status == IZIP_CLOSED)
 284                         return 1;
 285
 286                 unsigned char compr[CHUNK + 1];
 287
 288                 readresult = read(fd, compr, CHUNK);
 289
 290                 if (readresult > 0)
 291                 {
 292                         session->inbuf->AddData(compr, readresult);
 293
 294                         int size = session->inbuf->GetFrame(compr, CHUNK);
 295                         if (size)
 296                         {
 297
 298                                 session->d_stream.next_in  = (Bytef*)compr;
 299                                 session->d_stream.avail_in = 0;
 300                                 session->d_stream.next_out = (Bytef*)buffer;
 301                                 if (inflateInit(&session->d_stream) != Z_OK)
 302                                         return -EBADF;
 303
 304                                 while ((session->d_stream.total_out < count) && (session->d_stream.total_in < (unsigned int)size))
 305                                 {
 306                                         session->d_stream.avail_in = session->d_stream.avail_out = 1;
 307                                         if (inflate(&session->d_stream, Z_NO_FLUSH) == Z_STREAM_END)
 308                                                 break;
 309                                 }
 310
 311                                 inflateEnd(&session->d_stream);
 312
 313                                 total_in_compressed += readresult;
 314                                 readresult = session->d_stream.total_out;
 315                                 total_in_uncompressed += session->d_stream.total_out;
 316
 317                                 buffer[session->d_stream.total_out] = 0;
 318                         }
 319                 }
 320                 return (readresult > 0);
 321         }
 322
 323         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 324         {
 325                 izip_session* session = &sessions[fd];
 326                 int ocount = count;
 327
 328                 if (!count)
 329                 {
 330                         ServerInstance->Log(DEBUG,"Nothing to do!");
 331                         return 1;
 332                 }
 333
 334                 if(session->status != IZIP_OPEN)
 335                 {
 336                         CloseSession(session);
 337                         return 0;
 338                 }
 339
 340                 unsigned char compr[count*2+4];
 341
 342                 if (deflateInit(&session->c_stream, Z_BEST_COMPRESSION) != Z_OK)
 343                 {
 344                         ServerInstance->Log(DEBUG,"Deflate init failed");
 345                 }
 346
 347                 session->c_stream.next_in  = (Bytef*)buffer;
 348                 session->c_stream.next_out = compr+4;
 349
 350                 while ((session->c_stream.total_in < (unsigned int)count) && (session->c_stream.total_out < (unsigned int)count*2))
 351                 {
 352                         session->c_stream.avail_in = session->c_stream.avail_out = 1; /* force small buffers */
 353                         if (deflate(&session->c_stream, Z_NO_FLUSH) != Z_OK)
 354                         {
 355                                 ServerInstance->Log(DEBUG,"Couldnt deflate!");
 356                                 CloseSession(session);
 357                                 return 0;
 358                         }
 359                 }
 360                 /* Finish the stream, still forcing small buffers: */
 361                 for (;;)
 362                 {
 363                         session->c_stream.avail_out = 1;
 364                         if (deflate(&session->c_stream, Z_FINISH) == Z_STREAM_END)
 365                                 break;
 366                 }
 367
 368                 deflateEnd(&session->c_stream);
 369
 370                 total_out_uncompressed += ocount;
 371                 total_out_compressed += session->c_stream.total_out;
 372
 373                 int x = htonl(session->c_stream.total_out);
 374                 /** XXX: We memcpy it onto the start of the buffer like this to save ourselves a write().
 375                  * A memcpy of 4 or so bytes is less expensive and gives the tcp stack more chance of
 376                  * assembling the frame size into the same packet as the compressed frame.
 377                  */
 378                 memcpy(compr, &x, sizeof(x));
 379                 write(fd, compr, session->c_stream.total_out+4);
 380
 381                 return ocount;
 382         }
 383
 384         void CloseSession(izip_session* session)
 385         {
 386                 if (session->status = IZIP_OPEN)
 387                 {
 388                         session->status = IZIP_CLOSED;
 389                         delete session->inbuf;
 390                 }
 391         }
 392
 393 };
 394
 395 class ModuleZLibFactory : public ModuleFactory
 396 {
 397  public:
 398         ModuleZLibFactory()
 399         {
 400         }
 401
 402         ~ModuleZLibFactory()
 403         {
 404         }
 405
 406         virtual Module * CreateModule(InspIRCd* Me)
 407         {
 408                 return new ModuleZLib(Me);
 409         }
 410 };
 411
 412
 413 extern "C" void * init_module( void )
 414 {
 415         return new ModuleZLibFactory;
 416 }