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 = 128 * 1024;
  48
  49 class CountedBuffer : public classbase
  50 {
  51         std::deque<unsigned char> buffer; /* Current buffer contents */
  52         unsigned int amount_expected;   /* Amount of data expected */
  53  public:
  54         CountedBuffer()
  55         {
  56                 amount_expected = 0;
  57         }
  58
  59         void AddData(unsigned char* data, int data_length)
  60         {
  61                 SI->Log(DEBUG,"AddData, %d bytes to add", data_length);
  62                 for (int i = 0; i < data_length; i++)
  63                         buffer.push_back(data[i]);
  64
  65                 this->NextFrameSize();
  66         }
  67
  68         void NextFrameSize()
  69         {
  70                 if ((!amount_expected) && (buffer.size() >= 4))
  71                 {
  72                         SI->Log(DEBUG,"We dont yet have an expected amount");
  73                         /* We have enough to read an int */
  74                         char sz[4];
  75                         for (int i = 0; i < 4; i++)
  76                         {
  77                                 sz[i] = buffer.front();
  78                                 buffer.pop_front();
  79                         }
  80                         int* size = (int*)sz;
  81                         amount_expected = ntohl(*size);
  82                         SI->Log(DEBUG,"Expected amount is %d", amount_expected);
  83                 }
  84         }
  85
  86         int GetFrame(unsigned char* frame, int maxsize)
  87         {
  88                 if (amount_expected)
  89                 {
  90                         SI->Log(DEBUG,"Were expecting a frame of size %d", amount_expected);
  91                         /* We know how much we're expecting...
  92                          * Do we have enough yet?
  93                          */
  94                         if (buffer.size() >= amount_expected)
  95                         {
  96                                 int j = 0;
  97                                 for (unsigned int i = 0; i < amount_expected; i++, j++)
  98                                 {
  99                                         frame[i] = buffer.front();
 100                                         buffer.pop_front();
 101                                 }
 102
 103                                 NextFrameSize();
 104
 105                                 return j;
 106                         }
 107                 }
 108                 /* Not enough for a frame yet, COME AGAIN! */
 109                 return 0;
 110         }
 111 };
 112
 113 /** Represents an ZIP user's extra data
 114  */
 115 class izip_session : public classbase
 116 {
 117  public:
 118         z_stream c_stream; /* compression stream */
 119         z_stream d_stream; /* decompress stream */
 120         izip_status status;
 121         int fd;
 122         CountedBuffer* inbuf;
 123 };
 124
 125 class ModuleZLib : public Module
 126 {
 127         izip_session sessions[MAX_DESCRIPTORS];
 128         float total_out_compressed;
 129         float total_in_compressed;
 130         float total_out_uncompressed;
 131         float total_in_uncompressed;
 132
 133  public:
 134
 135         ModuleZLib(InspIRCd* Me)
 136                 : Module::Module(Me)
 137         {
 138                 ServerInstance->PublishInterface("InspSocketHook", this);
 139
 140                 total_out_compressed = total_in_compressed = 0;
 141                 total_out_uncompressed = total_out_uncompressed = 0;
 142
 143                 SI = ServerInstance;
 144         }
 145
 146         virtual ~ModuleZLib()
 147         {
 148         }
 149
 150         virtual Version GetVersion()
 151         {
 152                 return Version(1, 1, 0, 0, VF_VENDOR, API_VERSION);
 153         }
 154
 155         void Implements(char* List)
 156         {
 157                 List[I_OnRawSocketConnect] = List[I_OnRawSocketAccept] = List[I_OnRawSocketClose] = List[I_OnRawSocketRead] = List[I_OnRawSocketWrite] = 1;
 158                 List[I_OnStats] = List[I_OnRequest] = 1;
 159         }
 160
 161         virtual char* OnRequest(Request* request)
 162         {
 163                 ISHRequest* ISR = (ISHRequest*)request;
 164                 if (strcmp("IS_NAME", request->GetId()) == 0)
 165                 {
 166                         return "zip";
 167                 }
 168                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 169                 {
 170                         char* ret = "OK";
 171                         try
 172                         {
 173                                 ret = ServerInstance->Config->AddIOHook((Module*)this, (InspSocket*)ISR->Sock) ? (char*)"OK" : NULL;
 174                         }
 175                         catch (ModuleException& e)
 176                         {
 177                                 return NULL;
 178                         }
 179                         return ret;
 180                 }
 181                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 182                 {
 183                         return ServerInstance->Config->DelIOHook((InspSocket*)ISR->Sock) ? (char*)"OK" : NULL;
 184                 }
 185                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 186                 {
 187                         return "OK";
 188                 }
 189                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 190                 {
 191                         return NULL;
 192                 }
 193                 return NULL;
 194         }
 195
 196         virtual int OnStats(char symbol, userrec* user, string_list &results)
 197         {
 198                 if (symbol == 'z')
 199                 {
 200                         std::string sn = ServerInstance->Config->ServerName;
 201
 202                         float outbound_r = 100 - ((total_out_compressed / (total_out_uncompressed + 0.001)) * 100);
 203                         float inbound_r = 100 - ((total_in_compressed / (total_in_uncompressed + 0.001)) * 100);
 204
 205                         float total_compressed = total_in_compressed + total_out_compressed;
 206                         float total_uncompressed = total_in_uncompressed + total_out_uncompressed;
 207
 208                         float total_r = 100 - ((total_compressed / (total_uncompressed + 0.001)) * 100);
 209
 210                         char outbound_ratio[MAXBUF], inbound_ratio[MAXBUF], combined_ratio[MAXBUF];
 211
 212                         sprintf(outbound_ratio, "%3.2f%%", outbound_r);
 213                         sprintf(inbound_ratio, "%3.2f%%", inbound_r);
 214                         sprintf(combined_ratio, "%3.2f%%", total_r);
 215
 216                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_compressed   = "+ConvToStr(total_out_compressed));
 217                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_compressed    = "+ConvToStr(total_in_compressed));
 218                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_uncompressed = "+ConvToStr(total_out_uncompressed));
 219                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_uncompressed  = "+ConvToStr(total_in_uncompressed));
 220                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_ratio        = "+outbound_ratio);
 221                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_ratio         = "+inbound_ratio);
 222                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS combined_ratio        = "+combined_ratio);
 223                         return 0;
 224                 }
 225
 226                 return 0;
 227         }
 228
 229         virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
 230         {
 231                 izip_session* session = &sessions[fd];
 232
 233                 /* allocate deflate state */
 234                 session->fd = fd;
 235                 session->status = IZIP_OPEN;
 236
 237                 session->inbuf = new CountedBuffer();
 238                 ServerInstance->Log(DEBUG,"session->inbuf ALLOC = %d, %08x", fd, session->inbuf);
 239
 240                 session->c_stream.zalloc = (alloc_func)0;
 241                 session->c_stream.zfree = (free_func)0;
 242                 session->c_stream.opaque = (voidpf)0;
 243
 244                 session->d_stream.zalloc = (alloc_func)0;
 245                 session->d_stream.zfree = (free_func)0;
 246                 session->d_stream.opaque = (voidpf)0;
 247         }
 248
 249         virtual void OnRawSocketConnect(int fd)
 250         {
 251                 OnRawSocketAccept(fd, "", 0);
 252         }
 253
 254         virtual void OnRawSocketClose(int fd)
 255         {
 256                 CloseSession(&sessions[fd]);
 257         }
 258
 259         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 260         {
 261                 izip_session* session = &sessions[fd];
 262
 263                 if (session->status == IZIP_CLOSED)
 264                         return 1;
 265
 266                 unsigned char compr[CHUNK + 1];
 267                 unsigned int total_decomp = 0;
 268
 269                 readresult = read(fd, compr, CHUNK);
 270
 271                 if (readresult > 0)
 272                 {
 273                         session->inbuf->AddData(compr, readresult);
 274
 275                         int size = session->inbuf->GetFrame(compr, CHUNK);
 276                         while ((size) && (total_decomp < count))
 277                         {
 278
 279                                 session->d_stream.next_in  = (Bytef*)compr;
 280                                 session->d_stream.avail_in = 0;
 281                                 session->d_stream.next_out = (Bytef*)(buffer + total_decomp);
 282                                 if (inflateInit(&session->d_stream) != Z_OK)
 283                                         return -EBADF;
 284
 285                                 while ((session->d_stream.total_out < count) && (session->d_stream.total_in < (unsigned int)size))
 286                                 {
 287                                         session->d_stream.avail_in = session->d_stream.avail_out = 1;
 288                                         if (inflate(&session->d_stream, Z_NO_FLUSH) == Z_STREAM_END)
 289                                                 break;
 290                                 }
 291
 292                                 inflateEnd(&session->d_stream);
 293
 294                                 total_in_compressed += readresult;
 295                                 readresult = session->d_stream.total_out;
 296                                 total_in_uncompressed += session->d_stream.total_out;
 297
 298                                 total_decomp += session->d_stream.total_out;
 299
 300                                 ServerInstance->Log(DEBUG,"Decompressed %d bytes, total_decomp=%d: '%s'", session->d_stream.total_out, total_decomp, buffer);
 301
 302                                 if (total_decomp < count)
 303                                         size = session->inbuf->GetFrame(compr, CHUNK);
 304                         }
 305
 306                         buffer[total_decomp] = 0;
 307
 308                         ServerInstance->Log(DEBUG,"Complete buffer: '%s' size=%d", buffer, total_decomp);
 309                 }
 310                 return (readresult > 0);
 311         }
 312
 313         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 314         {
 315                 ServerInstance->Log(DEBUG,"Compressing %d bytes", count);
 316
 317                 izip_session* session = &sessions[fd];
 318                 int ocount = count;
 319
 320                 if (!count)
 321                 {
 322                         ServerInstance->Log(DEBUG,"Nothing to do!");
 323                         return 1;
 324                 }
 325
 326                 if(session->status != IZIP_OPEN)
 327                 {
 328                         CloseSession(session);
 329                         return 0;
 330                 }
 331
 332                 unsigned char compr[CHUNK];
 333
 334                 if (deflateInit(&session->c_stream, Z_BEST_COMPRESSION) != Z_OK)
 335                 {
 336                         ServerInstance->Log(DEBUG,"Deflate init failed");
 337                 }
 338
 339                 session->c_stream.next_in  = (Bytef*)buffer;
 340                 session->c_stream.next_out = compr+4;
 341
 342                 while ((session->c_stream.total_in < (unsigned int)count) && (session->c_stream.total_out < CHUNK))
 343                 {
 344                         session->c_stream.avail_in = session->c_stream.avail_out = 1; /* force small buffers */
 345                         if (deflate(&session->c_stream, Z_NO_FLUSH) != Z_OK)
 346                         {
 347                                 ServerInstance->Log(DEBUG,"Couldnt deflate!");
 348                                 CloseSession(session);
 349                                 return 0;
 350                         }
 351                 }
 352                 /* Finish the stream, still forcing small buffers: */
 353                 for (;;)
 354                 {
 355                         session->c_stream.avail_out = 1;
 356                         if (deflate(&session->c_stream, Z_FINISH) == Z_STREAM_END)
 357                                 break;
 358                 }
 359
 360                 deflateEnd(&session->c_stream);
 361
 362                 total_out_uncompressed += ocount;
 363                 total_out_compressed += session->c_stream.total_out;
 364
 365                 int x = htonl(session->c_stream.total_out);
 366                 /** XXX: We memcpy it onto the start of the buffer like this to save ourselves a write().
 367                  * A memcpy of 4 or so bytes is less expensive and gives the tcp stack more chance of
 368                  * assembling the frame size into the same packet as the compressed frame.
 369                  */
 370                 memcpy(compr, &x, sizeof(x));
 371                 write(fd, compr, session->c_stream.total_out+4);
 372
 373                 ServerInstance->Log(DEBUG,"Sending frame of size %d", x);
 374
 375                 return ocount;
 376         }
 377
 378         void CloseSession(izip_session* session)
 379         {
 380                 if (session->status = IZIP_OPEN)
 381                 {
 382                         session->status = IZIP_CLOSED;
 383                         delete session->inbuf;
 384                 }
 385         }
 386
 387 };
 388
 389 class ModuleZLibFactory : public ModuleFactory
 390 {
 391  public:
 392         ModuleZLibFactory()
 393         {
 394         }
 395
 396         ~ModuleZLibFactory()
 397         {
 398         }
 399
 400         virtual Module * CreateModule(InspIRCd* Me)
 401         {
 402                 return new ModuleZLib(Me);
 403         }
 404 };
 405
 406
 407 extern "C" void * init_module( void )
 408 {
 409         return new ModuleZLibFactory;
 410 }