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 enum izip_status { IZIP_OPEN, IZIP_CLOSED };
  44
  45 const unsigned int CHUNK = 128 * 1024;
  46
  47 class CountedBuffer : public classbase
  48 {
  49         std::deque<unsigned char> buffer; /* Current buffer contents */
  50         unsigned int amount_expected;   /* Amount of data expected */
  51  public:
  52         CountedBuffer()
  53         {
  54                 amount_expected = 0;
  55         }
  56
  57         void AddData(unsigned char* data, int data_length)
  58         {
  59                 for (int i = 0; i < data_length; i++)
  60                         buffer.push_back(data[i]);
  61
  62                 this->NextFrameSize();
  63         }
  64
  65         void NextFrameSize()
  66         {
  67                 if ((!amount_expected) && (buffer.size() >= 4))
  68                 {
  69                         /* We have enough to read an int */
  70                         char sz[4];
  71                         for (int i = 0; i < 4; i++)
  72                         {
  73                                 sz[i] = buffer.front();
  74                                 buffer.pop_front();
  75                         }
  76                         int* size = (int*)sz;
  77                         amount_expected = ntohl(*size);
  78                 }
  79         }
  80
  81         int GetFrame(unsigned char* frame, int maxsize)
  82         {
  83                 if (amount_expected)
  84                 {
  85                         /* We know how much we're expecting...
  86                          * Do we have enough yet?
  87                          */
  88                         if (buffer.size() >= amount_expected)
  89                         {
  90                                 int j = 0;
  91                                 for (unsigned int i = 0; i < amount_expected; i++, j++)
  92                                 {
  93                                         frame[i] = buffer.front();
  94                                         buffer.pop_front();
  95                                 }
  96
  97                                 amount_expected = 0;
  98                                 NextFrameSize();
  99
 100                                 return j;
 101                         }
 102                 }
 103                 /* Not enough for a frame yet, COME AGAIN! */
 104                 return 0;
 105         }
 106 };
 107
 108 /** Represents an ZIP user's extra data
 109  */
 110 class izip_session : public classbase
 111 {
 112  public:
 113         z_stream c_stream; /* compression stream */
 114         z_stream d_stream; /* decompress stream */
 115         izip_status status;
 116         int fd;
 117         CountedBuffer* inbuf;
 118 };
 119
 120 class ModuleZLib : public Module
 121 {
 122         izip_session sessions[MAX_DESCRIPTORS];
 123         float total_out_compressed;
 124         float total_in_compressed;
 125         float total_out_uncompressed;
 126         float total_in_uncompressed;
 127
 128  public:
 129
 130         ModuleZLib(InspIRCd* Me)
 131                 : Module::Module(Me)
 132         {
 133                 ServerInstance->PublishInterface("InspSocketHook", this);
 134
 135                 total_out_compressed = total_in_compressed = 0;
 136                 total_out_uncompressed = total_out_uncompressed = 0;
 137         }
 138
 139         virtual ~ModuleZLib()
 140         {
 141         }
 142
 143         virtual Version GetVersion()
 144         {
 145                 return Version(1, 1, 0, 0, VF_VENDOR, API_VERSION);
 146         }
 147
 148         void Implements(char* List)
 149         {
 150                 List[I_OnRawSocketConnect] = List[I_OnRawSocketAccept] = List[I_OnRawSocketClose] = List[I_OnRawSocketRead] = List[I_OnRawSocketWrite] = 1;
 151                 List[I_OnStats] = List[I_OnRequest] = 1;
 152         }
 153
 154         virtual char* OnRequest(Request* request)
 155         {
 156                 ISHRequest* ISR = (ISHRequest*)request;
 157                 if (strcmp("IS_NAME", request->GetId()) == 0)
 158                 {
 159                         return "zip";
 160                 }
 161                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 162                 {
 163                         char* ret = "OK";
 164                         try
 165                         {
 166                                 ret = ServerInstance->Config->AddIOHook((Module*)this, (InspSocket*)ISR->Sock) ? (char*)"OK" : NULL;
 167                         }
 168                         catch (ModuleException& e)
 169                         {
 170                                 return NULL;
 171                         }
 172                         return ret;
 173                 }
 174                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 175                 {
 176                         return ServerInstance->Config->DelIOHook((InspSocket*)ISR->Sock) ? (char*)"OK" : NULL;
 177                 }
 178                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 179                 {
 180                         return "OK";
 181                 }
 182                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 183                 {
 184                         return NULL;
 185                 }
 186                 return NULL;
 187         }
 188
 189         virtual int OnStats(char symbol, userrec* user, string_list &results)
 190         {
 191                 if (symbol == 'z')
 192                 {
 193                         std::string sn = ServerInstance->Config->ServerName;
 194
 195                         float outbound_r = 100 - ((total_out_compressed / (total_out_uncompressed + 0.001)) * 100);
 196                         float inbound_r = 100 - ((total_in_compressed / (total_in_uncompressed + 0.001)) * 100);
 197
 198                         float total_compressed = total_in_compressed + total_out_compressed;
 199                         float total_uncompressed = total_in_uncompressed + total_out_uncompressed;
 200
 201                         float total_r = 100 - ((total_compressed / (total_uncompressed + 0.001)) * 100);
 202
 203                         char outbound_ratio[MAXBUF], inbound_ratio[MAXBUF], combined_ratio[MAXBUF];
 204
 205                         sprintf(outbound_ratio, "%3.2f%%", outbound_r);
 206                         sprintf(inbound_ratio, "%3.2f%%", inbound_r);
 207                         sprintf(combined_ratio, "%3.2f%%", total_r);
 208
 209                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_compressed   = "+ConvToStr(total_out_compressed));
 210                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_compressed    = "+ConvToStr(total_in_compressed));
 211                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_uncompressed = "+ConvToStr(total_out_uncompressed));
 212                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_uncompressed  = "+ConvToStr(total_in_uncompressed));
 213                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_ratio        = "+outbound_ratio);
 214                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_ratio         = "+inbound_ratio);
 215                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS combined_ratio        = "+combined_ratio);
 216                         return 0;
 217                 }
 218
 219                 return 0;
 220         }
 221
 222         virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
 223         {
 224                 izip_session* session = &sessions[fd];
 225
 226                 /* allocate deflate state */
 227                 session->fd = fd;
 228                 session->status = IZIP_OPEN;
 229
 230                 session->inbuf = new CountedBuffer();
 231                 ServerInstance->Log(DEBUG,"session->inbuf ALLOC = %d, %08x", fd, session->inbuf);
 232
 233                 session->c_stream.zalloc = (alloc_func)0;
 234                 session->c_stream.zfree = (free_func)0;
 235                 session->c_stream.opaque = (voidpf)0;
 236
 237                 session->d_stream.zalloc = (alloc_func)0;
 238                 session->d_stream.zfree = (free_func)0;
 239                 session->d_stream.opaque = (voidpf)0;
 240         }
 241
 242         virtual void OnRawSocketConnect(int fd)
 243         {
 244                 OnRawSocketAccept(fd, "", 0);
 245         }
 246
 247         virtual void OnRawSocketClose(int fd)
 248         {
 249                 CloseSession(&sessions[fd]);
 250         }
 251
 252         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 253         {
 254                 izip_session* session = &sessions[fd];
 255
 256                 if (session->status == IZIP_CLOSED)
 257                         return 1;
 258
 259                 unsigned char compr[CHUNK + 1];
 260
 261                 readresult = read(fd, compr, CHUNK);
 262
 263                 if (readresult > 0)
 264                 {
 265                         session->inbuf->AddData(compr, readresult);
 266
 267                         int size = 0;
 268                         std::string str_out;
 269                         while ((size = session->inbuf->GetFrame(compr, CHUNK)) != 0)
 270                         {
 271                                 unsigned char localbuf[count + 1];
 272
 273                                 session->d_stream.next_in  = (Bytef*)compr;
 274                                 session->d_stream.avail_in = 0;
 275                                 session->d_stream.next_out = (Bytef*)localbuf;
 276                                 if (inflateInit(&session->d_stream) != Z_OK)
 277                                         return -EBADF;
 278
 279                                 while ((session->d_stream.total_out < count) && (session->d_stream.total_in < (unsigned int)size))
 280                                 {
 281                                         session->d_stream.avail_in = session->d_stream.avail_out = 1;
 282                                         if (inflate(&session->d_stream, Z_NO_FLUSH) == Z_STREAM_END)
 283                                                 break;
 284                                 }
 285
 286                                 inflateEnd(&session->d_stream);
 287
 288                                 localbuf[session->d_stream.total_out] = 0;
 289                                 str_out.append((const char*)localbuf);
 290                                 total_in_compressed += readresult;
 291                                 readresult = session->d_stream.total_out;
 292                                 total_in_uncompressed += session->d_stream.total_out;
 293                         }
 294
 295                         memcpy(buffer, str_out.data(), str_out.length() > count ? count : str_out.length());
 296                         readresult = str_out.length();
 297                 }
 298                 return (readresult > 0);
 299         }
 300
 301         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 302         {
 303                 ServerInstance->Log(DEBUG,"Compressing %d bytes", count);
 304
 305                 izip_session* session = &sessions[fd];
 306                 int ocount = count;
 307
 308                 if (!count)
 309                 {
 310                         ServerInstance->Log(DEBUG,"Nothing to do!");
 311                         return 1;
 312                 }
 313
 314                 if(session->status != IZIP_OPEN)
 315                 {
 316                         CloseSession(session);
 317                         return 0;
 318                 }
 319
 320                 unsigned char compr[CHUNK];
 321
 322                 if (deflateInit(&session->c_stream, Z_BEST_COMPRESSION) != Z_OK)
 323                 {
 324                         ServerInstance->Log(DEBUG,"Deflate init failed");
 325                 }
 326
 327                 session->c_stream.next_in  = (Bytef*)buffer;
 328                 session->c_stream.next_out = compr+4;
 329
 330                 while ((session->c_stream.total_in < (unsigned int)count) && (session->c_stream.total_out < CHUNK))
 331                 {
 332                         session->c_stream.avail_in = session->c_stream.avail_out = 1; /* force small buffers */
 333                         if (deflate(&session->c_stream, Z_NO_FLUSH) != Z_OK)
 334                         {
 335                                 ServerInstance->Log(DEBUG,"Couldnt deflate!");
 336                                 CloseSession(session);
 337                                 return 0;
 338                         }
 339                 }
 340                 /* Finish the stream, still forcing small buffers: */
 341                 for (;;)
 342                 {
 343                         session->c_stream.avail_out = 1;
 344                         if (deflate(&session->c_stream, Z_FINISH) == Z_STREAM_END)
 345                                 break;
 346                 }
 347
 348                 deflateEnd(&session->c_stream);
 349
 350                 total_out_uncompressed += ocount;
 351                 total_out_compressed += session->c_stream.total_out;
 352
 353                 int x = htonl(session->c_stream.total_out);
 354                 /** XXX: We memcpy it onto the start of the buffer like this to save ourselves a write().
 355                  * A memcpy of 4 or so bytes is less expensive and gives the tcp stack more chance of
 356                  * assembling the frame size into the same packet as the compressed frame.
 357                  */
 358                 memcpy(compr, &x, sizeof(x));
 359                 write(fd, compr, session->c_stream.total_out+4);
 360
 361                 ServerInstance->Log(DEBUG,"Sending frame of size %d", ntohl(x));
 362
 363                 return ocount;
 364         }
 365
 366         void CloseSession(izip_session* session)
 367         {
 368                 if (session->status = IZIP_OPEN)
 369                 {
 370                         session->status = IZIP_CLOSED;
 371                         delete session->inbuf;
 372                 }
 373         }
 374
 375 };
 376
 377 class ModuleZLibFactory : public ModuleFactory
 378 {
 379  public:
 380         ModuleZLibFactory()
 381         {
 382         }
 383
 384         ~ModuleZLibFactory()
 385         {
 386         }
 387
 388         virtual Module * CreateModule(InspIRCd* Me)
 389         {
 390                 return new ModuleZLib(Me);
 391         }
 392 };
 393
 394
 395 extern "C" void * init_module( void )
 396 {
 397         return new ModuleZLibFactory;
 398 }