src/modules/extra/m_ziplink.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd is copyright (C) 2002-2006 ChatSpike-Dev.
   6  *                       E-mail:
   7  *                <brain@chatspike.net>
   8  *                <Craig@chatspike.net>
   9  *
  10  * Written by Craig Edwards, Craig McLure, and others.
  11  * This program is free but copyrighted software; see
  12  *            the file COPYING for details.
  13  *
  14  * ---------------------------------------------------
  15  */
  16
  17 #include <string>
  18 #include <vector>
  19
  20 #include "zlib.h"
  21
  22 #include "inspircd_config.h"
  23 #include "configreader.h"
  24 #include "users.h"
  25 #include "channels.h"
  26 #include "modules.h"
  27
  28 #include "socket.h"
  29 #include "hashcomp.h"
  30 #include "inspircd.h"
  31
  32 #include "transport.h"
  33
  34 /* $ModDesc: Provides zlib link support for servers */
  35 /* $LinkerFlags: -lz */
  36 /* $ModDep: transport.h */
  37
  38 /*
  39  * Compressed data is transmitted across the link in the following format:
  40  *
  41  *   0   1   2   3   4 ... n
  42  * +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
  43  * |       n       |              Z0 -> Zn                         |
  44  * +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
  45  *
  46  * Where: n is the size of a frame, in network byte order, 4 bytes.
  47  * Z0 through Zn are Zlib compressed data, n bytes in length.
  48  *
  49  * If the module fails to read the entire frame, then it will buffer
  50  * the portion of the last frame it received, then attempt to read
  51  * the next part of the frame next time a write notification arrives.
  52  *
  53  * ZLIB_BEST_COMPRESSION (9) is used for all sending of data with
  54  * a flush after each frame. A frame may contain multiple lines
  55  * and should be treated as raw binary data.
  56  *
  57  */
  58
  59 enum izip_status { IZIP_OPEN, IZIP_CLOSED };
  60
  61 const unsigned int CHUNK = 128 * 1024;
  62
  63 class CountedBuffer : public classbase
  64 {
  65         std::deque<unsigned char> buffer; /* Current buffer contents */
  66         unsigned int amount_expected;   /* Amount of data expected */
  67  public:
  68         CountedBuffer()
  69         {
  70                 amount_expected = 0;
  71         }
  72
  73         void AddData(unsigned char* data, int data_length)
  74         {
  75                 for (int i = 0; i < data_length; i++)
  76                         buffer.push_back(data[i]);
  77
  78                 this->NextFrameSize();
  79         }
  80
  81         void NextFrameSize()
  82         {
  83                 if ((!amount_expected) && (buffer.size() >= 4))
  84                 {
  85                         /* We have enough to read an int */
  86                         char sz[4];
  87                         for (int i = 0; i < 4; i++)
  88                         {
  89                                 sz[i] = buffer.front();
  90                                 buffer.pop_front();
  91                         }
  92                         int* size = (int*)sz;
  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 (buffer.size() >= amount_expected)
 105                         {
 106                                 int j = 0;
 107                                 for (unsigned int i = 0; i < amount_expected; i++, j++)
 108                                 {
 109                                         frame[i] = buffer.front();
 110                                         buffer.pop_front();
 111                                 }
 112
 113                                 amount_expected = 0;
 114                                 NextFrameSize();
 115
 116                                 return j;
 117                         }
 118                 }
 119                 /* Not enough for a frame yet, COME AGAIN! */
 120                 return 0;
 121         }
 122 };
 123
 124 /** Represents an ZIP user's extra data
 125  */
 126 class izip_session : public classbase
 127 {
 128  public:
 129         z_stream c_stream; /* compression stream */
 130         z_stream d_stream; /* decompress stream */
 131         izip_status status;
 132         int fd;
 133         CountedBuffer* inbuf;
 134         std::string outbuf;
 135 };
 136
 137 class ModuleZLib : public Module
 138 {
 139         izip_session sessions[MAX_DESCRIPTORS];
 140         float total_out_compressed;
 141         float total_in_compressed;
 142         float total_out_uncompressed;
 143         float total_in_uncompressed;
 144
 145  public:
 146
 147         ModuleZLib(InspIRCd* Me)
 148                 : Module::Module(Me)
 149         {
 150                 ServerInstance->PublishInterface("InspSocketHook", this);
 151
 152                 total_out_compressed = total_in_compressed = 0;
 153                 total_out_uncompressed = total_out_uncompressed = 0;
 154         }
 155
 156         virtual ~ModuleZLib()
 157         {
 158         }
 159
 160         virtual Version GetVersion()
 161         {
 162                 return Version(1, 1, 0, 0, VF_VENDOR, API_VERSION);
 163         }
 164
 165         void Implements(char* List)
 166         {
 167                 List[I_OnRawSocketConnect] = List[I_OnRawSocketAccept] = List[I_OnRawSocketClose] = List[I_OnRawSocketRead] = List[I_OnRawSocketWrite] = 1;
 168                 List[I_OnStats] = List[I_OnRequest] = 1;
 169         }
 170
 171         virtual char* OnRequest(Request* request)
 172         {
 173                 ISHRequest* ISR = (ISHRequest*)request;
 174                 if (strcmp("IS_NAME", request->GetId()) == 0)
 175                 {
 176                         return "zip";
 177                 }
 178                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 179                 {
 180                         char* ret = "OK";
 181                         try
 182                         {
 183                                 ret = ServerInstance->Config->AddIOHook((Module*)this, (InspSocket*)ISR->Sock) ? (char*)"OK" : NULL;
 184                         }
 185                         catch (ModuleException& e)
 186                         {
 187                                 return NULL;
 188                         }
 189                         return ret;
 190                 }
 191                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 192                 {
 193                         return ServerInstance->Config->DelIOHook((InspSocket*)ISR->Sock) ? (char*)"OK" : NULL;
 194                 }
 195                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 196                 {
 197                         return "OK";
 198                 }
 199                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 200                 {
 201                         return NULL;
 202                 }
 203                 return NULL;
 204         }
 205
 206         virtual int OnStats(char symbol, userrec* user, string_list &results)
 207         {
 208                 if (symbol == 'z')
 209                 {
 210                         std::string sn = ServerInstance->Config->ServerName;
 211
 212                         float outbound_r = 100 - ((total_out_compressed / (total_out_uncompressed + 0.001)) * 100);
 213                         float inbound_r = 100 - ((total_in_compressed / (total_in_uncompressed + 0.001)) * 100);
 214
 215                         float total_compressed = total_in_compressed + total_out_compressed;
 216                         float total_uncompressed = total_in_uncompressed + total_out_uncompressed;
 217
 218                         float total_r = 100 - ((total_compressed / (total_uncompressed + 0.001)) * 100);
 219
 220                         char outbound_ratio[MAXBUF], inbound_ratio[MAXBUF], combined_ratio[MAXBUF];
 221
 222                         sprintf(outbound_ratio, "%3.2f%%", outbound_r);
 223                         sprintf(inbound_ratio, "%3.2f%%", inbound_r);
 224                         sprintf(combined_ratio, "%3.2f%%", total_r);
 225
 226                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_compressed   = "+ConvToStr(total_out_compressed));
 227                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_compressed    = "+ConvToStr(total_in_compressed));
 228                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_uncompressed = "+ConvToStr(total_out_uncompressed));
 229                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_uncompressed  = "+ConvToStr(total_in_uncompressed));
 230                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_ratio        = "+outbound_ratio);
 231                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_ratio         = "+inbound_ratio);
 232                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS combined_ratio        = "+combined_ratio);
 233                         return 0;
 234                 }
 235
 236                 return 0;
 237         }
 238
 239         virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
 240         {
 241                 izip_session* session = &sessions[fd];
 242
 243                 /* allocate deflate state */
 244                 session->fd = fd;
 245                 session->status = IZIP_OPEN;
 246
 247                 session->inbuf = new CountedBuffer();
 248                 ServerInstance->Log(DEBUG,"session->inbuf ALLOC = %d, %08x", fd, session->inbuf);
 249
 250                 session->c_stream.zalloc = (alloc_func)0;
 251                 session->c_stream.zfree = (free_func)0;
 252                 session->c_stream.opaque = (voidpf)0;
 253
 254                 session->d_stream.zalloc = (alloc_func)0;
 255                 session->d_stream.zfree = (free_func)0;
 256                 session->d_stream.opaque = (voidpf)0;
 257         }
 258
 259         virtual void OnRawSocketConnect(int fd)
 260         {
 261                 OnRawSocketAccept(fd, "", 0);
 262         }
 263
 264         virtual void OnRawSocketClose(int fd)
 265         {
 266                 CloseSession(&sessions[fd]);
 267         }
 268
 269         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 270         {
 271                 izip_session* session = &sessions[fd];
 272
 273                 if (session->status == IZIP_CLOSED)
 274                         return 1;
 275
 276                 unsigned char compr[CHUNK + 1];
 277
 278                 readresult = read(fd, compr, CHUNK);
 279
 280                 if (readresult > 0)
 281                 {
 282                         session->inbuf->AddData(compr, readresult);
 283
 284                         int size = 0;
 285                         std::string str_out;
 286                         while ((size = session->inbuf->GetFrame(compr, CHUNK)) != 0)
 287                         {
 288                                 unsigned char localbuf[count + 1];
 289
 290                                 session->d_stream.next_in  = (Bytef*)compr;
 291                                 session->d_stream.avail_in = 0;
 292                                 session->d_stream.next_out = (Bytef*)localbuf;
 293                                 if (inflateInit(&session->d_stream) != Z_OK)
 294                                         return -EBADF;
 295
 296                                 while ((session->d_stream.total_out < count) && (session->d_stream.total_in < (unsigned int)size))
 297                                 {
 298                                         session->d_stream.avail_in = session->d_stream.avail_out = 1;
 299                                         if (inflate(&session->d_stream, Z_NO_FLUSH) == Z_STREAM_END)
 300                                                 break;
 301                                 }
 302
 303                                 inflateEnd(&session->d_stream);
 304
 305                                 localbuf[session->d_stream.total_out] = 0;
 306                                 str_out.append((const char*)localbuf);
 307                                 total_in_compressed += readresult;
 308                                 readresult = session->d_stream.total_out;
 309                                 total_in_uncompressed += session->d_stream.total_out;
 310                         }
 311
 312                         memcpy(buffer, str_out.data(), str_out.length() > count ? count : str_out.length());
 313                         readresult = str_out.length();
 314                 }
 315                 return (readresult > 0);
 316         }
 317
 318         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 319         {
 320                 ServerInstance->Log(DEBUG,"Compressing %d bytes", count);
 321
 322                 izip_session* session = &sessions[fd];
 323                 int ocount = count;
 324
 325                 if (!count)
 326                 {
 327                         ServerInstance->Log(DEBUG,"Nothing to do!");
 328                         return 1;
 329                 }
 330
 331                 if(session->status != IZIP_OPEN)
 332                 {
 333                         CloseSession(session);
 334                         return 0;
 335                 }
 336
 337                 unsigned char compr[CHUNK];
 338
 339                 if (deflateInit(&session->c_stream, Z_BEST_COMPRESSION) != Z_OK)
 340                 {
 341                         ServerInstance->Log(DEBUG,"Deflate init failed");
 342                 }
 343
 344                 session->c_stream.next_in  = (Bytef*)buffer;
 345                 session->c_stream.next_out = compr+4;
 346
 347                 while ((session->c_stream.total_in < (unsigned int)count) && (session->c_stream.total_out < CHUNK))
 348                 {
 349                         session->c_stream.avail_in = session->c_stream.avail_out = 1; /* force small buffers */
 350                         if (deflate(&session->c_stream, Z_NO_FLUSH) != Z_OK)
 351                         {
 352                                 ServerInstance->Log(DEBUG,"Couldnt deflate!");
 353                                 CloseSession(session);
 354                                 return 0;
 355                         }
 356                 }
 357                 /* Finish the stream, still forcing small buffers: */
 358                 for (;;)
 359                 {
 360                         session->c_stream.avail_out = 1;
 361                         if (deflate(&session->c_stream, Z_FINISH) == Z_STREAM_END)
 362                                 break;
 363                 }
 364
 365                 deflateEnd(&session->c_stream);
 366
 367                 total_out_uncompressed += ocount;
 368                 total_out_compressed += session->c_stream.total_out;
 369
 370                 int x = htonl(session->c_stream.total_out);
 371                 /** XXX: We memcpy it onto the start of the buffer like this to save ourselves a write().
 372                  * A memcpy of 4 or so bytes is less expensive and gives the tcp stack more chance of
 373                  * assembling the frame size into the same packet as the compressed frame.
 374                  */
 375                 memcpy(compr, &x, sizeof(x));
 376
 377                 const char* string_likes_signed_chars = (const char*)compr;
 378                 session->outbuf.append(string_likes_signed_chars, session->c_stream.total_out+4);
 379
 380                 int ret = write(fd, session->outbuf.data(), session->outbuf.length());
 381
 382                 if (ret > 0)
 383                         session->outbuf = session->outbuf.substr(ret);
 384                 else if (ret < 1)
 385                 {
 386                         if (ret == -1)
 387                                 return errno == EAGAIN;
 388                         else
 389                                 return 0;
 390                 }
 391
 392                 ServerInstance->Log(DEBUG,"Sending frame of size %d", ntohl(x));
 393
 394                 /* ALL LIES the lot of it, we havent really written
 395                  * this amount, but the layer above doesnt need to know.
 396                  */
 397                 return ocount;
 398         }
 399
 400         void CloseSession(izip_session* session)
 401         {
 402                 if (session->status = IZIP_OPEN)
 403                 {
 404                         session->status = IZIP_CLOSED;
 405                         session->outbuf = "";
 406                         delete session->inbuf;
 407                 }
 408         }
 409
 410 };
 411
 412 class ModuleZLibFactory : public ModuleFactory
 413 {
 414  public:
 415         ModuleZLibFactory()
 416         {
 417         }
 418
 419         ~ModuleZLibFactory()
 420         {
 421         }
 422
 423         virtual Module * CreateModule(InspIRCd* Me)
 424         {
 425                 return new ModuleZLib(Me);
 426         }
 427 };
 428
 429
 430 extern "C" void * init_module( void )
 431 {
 432         return new ModuleZLibFactory;
 433 }