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