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         std::string outbuf;
 119 };
 120
 121 class ModuleZLib : public Module
 122 {
 123         izip_session sessions[MAX_DESCRIPTORS];
 124         float total_out_compressed;
 125         float total_in_compressed;
 126         float total_out_uncompressed;
 127         float total_in_uncompressed;
 128
 129  public:
 130
 131         ModuleZLib(InspIRCd* Me)
 132                 : Module::Module(Me)
 133         {
 134                 ServerInstance->PublishInterface("InspSocketHook", this);
 135
 136                 total_out_compressed = total_in_compressed = 0;
 137                 total_out_uncompressed = total_out_uncompressed = 0;
 138         }
 139
 140         virtual ~ModuleZLib()
 141         {
 142         }
 143
 144         virtual Version GetVersion()
 145         {
 146                 return Version(1, 1, 0, 0, VF_VENDOR, API_VERSION);
 147         }
 148
 149         void Implements(char* List)
 150         {
 151                 List[I_OnRawSocketConnect] = List[I_OnRawSocketAccept] = List[I_OnRawSocketClose] = List[I_OnRawSocketRead] = List[I_OnRawSocketWrite] = 1;
 152                 List[I_OnStats] = List[I_OnRequest] = 1;
 153         }
 154
 155         virtual char* OnRequest(Request* request)
 156         {
 157                 ISHRequest* ISR = (ISHRequest*)request;
 158                 if (strcmp("IS_NAME", request->GetId()) == 0)
 159                 {
 160                         return "zip";
 161                 }
 162                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 163                 {
 164                         char* ret = "OK";
 165                         try
 166                         {
 167                                 ret = ServerInstance->Config->AddIOHook((Module*)this, (InspSocket*)ISR->Sock) ? (char*)"OK" : NULL;
 168                         }
 169                         catch (ModuleException& e)
 170                         {
 171                                 return NULL;
 172                         }
 173                         return ret;
 174                 }
 175                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 176                 {
 177                         return ServerInstance->Config->DelIOHook((InspSocket*)ISR->Sock) ? (char*)"OK" : NULL;
 178                 }
 179                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 180                 {
 181                         return "OK";
 182                 }
 183                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 184                 {
 185                         return NULL;
 186                 }
 187                 return NULL;
 188         }
 189
 190         virtual int OnStats(char symbol, userrec* user, string_list &results)
 191         {
 192                 if (symbol == 'z')
 193                 {
 194                         std::string sn = ServerInstance->Config->ServerName;
 195
 196                         float outbound_r = 100 - ((total_out_compressed / (total_out_uncompressed + 0.001)) * 100);
 197                         float inbound_r = 100 - ((total_in_compressed / (total_in_uncompressed + 0.001)) * 100);
 198
 199                         float total_compressed = total_in_compressed + total_out_compressed;
 200                         float total_uncompressed = total_in_uncompressed + total_out_uncompressed;
 201
 202                         float total_r = 100 - ((total_compressed / (total_uncompressed + 0.001)) * 100);
 203
 204                         char outbound_ratio[MAXBUF], inbound_ratio[MAXBUF], combined_ratio[MAXBUF];
 205
 206                         sprintf(outbound_ratio, "%3.2f%%", outbound_r);
 207                         sprintf(inbound_ratio, "%3.2f%%", inbound_r);
 208                         sprintf(combined_ratio, "%3.2f%%", total_r);
 209
 210                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_compressed   = "+ConvToStr(total_out_compressed));
 211                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_compressed    = "+ConvToStr(total_in_compressed));
 212                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_uncompressed = "+ConvToStr(total_out_uncompressed));
 213                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_uncompressed  = "+ConvToStr(total_in_uncompressed));
 214                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_ratio        = "+outbound_ratio);
 215                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_ratio         = "+inbound_ratio);
 216                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS combined_ratio        = "+combined_ratio);
 217                         return 0;
 218                 }
 219
 220                 return 0;
 221         }
 222
 223         virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
 224         {
 225                 izip_session* session = &sessions[fd];
 226
 227                 /* allocate deflate state */
 228                 session->fd = fd;
 229                 session->status = IZIP_OPEN;
 230
 231                 session->inbuf = new CountedBuffer();
 232                 ServerInstance->Log(DEBUG,"session->inbuf ALLOC = %d, %08x", fd, session->inbuf);
 233
 234                 session->c_stream.zalloc = (alloc_func)0;
 235                 session->c_stream.zfree = (free_func)0;
 236                 session->c_stream.opaque = (voidpf)0;
 237
 238                 session->d_stream.zalloc = (alloc_func)0;
 239                 session->d_stream.zfree = (free_func)0;
 240                 session->d_stream.opaque = (voidpf)0;
 241         }
 242
 243         virtual void OnRawSocketConnect(int fd)
 244         {
 245                 OnRawSocketAccept(fd, "", 0);
 246         }
 247
 248         virtual void OnRawSocketClose(int fd)
 249         {
 250                 CloseSession(&sessions[fd]);
 251         }
 252
 253         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 254         {
 255                 izip_session* session = &sessions[fd];
 256
 257                 if (session->status == IZIP_CLOSED)
 258                         return 1;
 259
 260                 unsigned char compr[CHUNK + 1];
 261
 262                 readresult = read(fd, compr, CHUNK);
 263
 264                 if (readresult > 0)
 265                 {
 266                         session->inbuf->AddData(compr, readresult);
 267
 268                         int size = 0;
 269                         std::string str_out;
 270                         while ((size = session->inbuf->GetFrame(compr, CHUNK)) != 0)
 271                         {
 272                                 unsigned char localbuf[count + 1];
 273
 274                                 session->d_stream.next_in  = (Bytef*)compr;
 275                                 session->d_stream.avail_in = 0;
 276                                 session->d_stream.next_out = (Bytef*)localbuf;
 277                                 if (inflateInit(&session->d_stream) != Z_OK)
 278                                         return -EBADF;
 279
 280                                 while ((session->d_stream.total_out < count) && (session->d_stream.total_in < (unsigned int)size))
 281                                 {
 282                                         session->d_stream.avail_in = session->d_stream.avail_out = 1;
 283                                         if (inflate(&session->d_stream, Z_NO_FLUSH) == Z_STREAM_END)
 284                                                 break;
 285                                 }
 286
 287                                 inflateEnd(&session->d_stream);
 288
 289                                 localbuf[session->d_stream.total_out] = 0;
 290                                 str_out.append((const char*)localbuf);
 291                                 total_in_compressed += readresult;
 292                                 readresult = session->d_stream.total_out;
 293                                 total_in_uncompressed += session->d_stream.total_out;
 294                         }
 295
 296                         memcpy(buffer, str_out.data(), str_out.length() > count ? count : str_out.length());
 297                         readresult = str_out.length();
 298                 }
 299                 return (readresult > 0);
 300         }
 301
 302         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 303         {
 304                 ServerInstance->Log(DEBUG,"Compressing %d bytes", count);
 305
 306                 izip_session* session = &sessions[fd];
 307                 int ocount = count;
 308
 309                 if (!count)
 310                 {
 311                         ServerInstance->Log(DEBUG,"Nothing to do!");
 312                         return 1;
 313                 }
 314
 315                 if(session->status != IZIP_OPEN)
 316                 {
 317                         CloseSession(session);
 318                         return 0;
 319                 }
 320
 321                 unsigned char compr[CHUNK];
 322
 323                 if (deflateInit(&session->c_stream, Z_BEST_COMPRESSION) != Z_OK)
 324                 {
 325                         ServerInstance->Log(DEBUG,"Deflate init failed");
 326                 }
 327
 328                 session->c_stream.next_in  = (Bytef*)buffer;
 329                 session->c_stream.next_out = compr+4;
 330
 331                 while ((session->c_stream.total_in < (unsigned int)count) && (session->c_stream.total_out < CHUNK))
 332                 {
 333                         session->c_stream.avail_in = session->c_stream.avail_out = 1; /* force small buffers */
 334                         if (deflate(&session->c_stream, Z_NO_FLUSH) != Z_OK)
 335                         {
 336                                 ServerInstance->Log(DEBUG,"Couldnt deflate!");
 337                                 CloseSession(session);
 338                                 return 0;
 339                         }
 340                 }
 341                 /* Finish the stream, still forcing small buffers: */
 342                 for (;;)
 343                 {
 344                         session->c_stream.avail_out = 1;
 345                         if (deflate(&session->c_stream, Z_FINISH) == Z_STREAM_END)
 346                                 break;
 347                 }
 348
 349                 deflateEnd(&session->c_stream);
 350
 351                 total_out_uncompressed += ocount;
 352                 total_out_compressed += session->c_stream.total_out;
 353
 354                 int x = htonl(session->c_stream.total_out);
 355                 /** XXX: We memcpy it onto the start of the buffer like this to save ourselves a write().
 356                  * A memcpy of 4 or so bytes is less expensive and gives the tcp stack more chance of
 357                  * assembling the frame size into the same packet as the compressed frame.
 358                  */
 359                 memcpy(compr, &x, sizeof(x));
 360
 361                 const char* string_likes_signed_chars = (const char*)compr;
 362                 session->outbuf.append(string_likes_signed_chars, session->c_stream.total_out+4);
 363
 364                 int ret = write(fd, session->outbuf.data(), session->outbuf.length());
 365
 366                 if (ret > 0)
 367                         session->outbuf = session->outbuf.substr(ret);
 368                 else if (ret < 1)
 369                 {
 370                         if (ret == -1)
 371                                 return errno == EAGAIN;
 372                         else
 373                                 return 0;
 374                 }
 375
 376                 ServerInstance->Log(DEBUG,"Sending frame of size %d", ntohl(x));
 377
 378                 /* ALL LIES the lot of it, we havent really written
 379                  * this amount, but the layer above doesnt need to know.
 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                         session->outbuf = "";
 390                         delete session->inbuf;
 391                 }
 392         }
 393
 394 };
 395
 396 class ModuleZLibFactory : public ModuleFactory
 397 {
 398  public:
 399         ModuleZLibFactory()
 400         {
 401         }
 402
 403         ~ModuleZLibFactory()
 404         {
 405         }
 406
 407         virtual Module * CreateModule(InspIRCd* Me)
 408         {
 409                 return new ModuleZLib(Me);
 410         }
 411 };
 412
 413
 414 extern "C" void * init_module( void )
 415 {
 416         return new ModuleZLibFactory;
 417 }