src/modules/extra/m_ziplink.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2008 InspIRCd Development Team
   6  * See: http://www.inspircd.org/wiki/index.php/Credits
   7  *
   8  * This program is free but copyrighted software; see
   9  *            the file COPYING for details.
  10  *
  11  * ---------------------------------------------------
  12  */
  13
  14 #include "inspircd.h"
  15 #include <zlib.h>
  16 #include "users.h"
  17 #include "channels.h"
  18 #include "modules.h"
  19 #include "socket.h"
  20 #include "hashcomp.h"
  21 #include "transport.h"
  22
  23 #include <iostream>
  24
  25 /* $ModDesc: Provides zlib link support for servers */
  26 /* $LinkerFlags: -lz */
  27 /* $ModDep: transport.h */
  28
  29 /*
  30  * ZLIB_BEST_COMPRESSION (9) is used for all sending of data with
  31  * a flush after each chunk. A frame may contain multiple lines
  32  * and should be treated as raw binary data.
  33  */
  34
  35 /* Status of a connection */
  36 enum izip_status { IZIP_CLOSED = 0, IZIP_OPEN };
  37
  38 /* Maximum transfer size per read operation */
  39 const unsigned int CHUNK = 128 * 1024;
  40
  41 /** Represents an zipped connections extra data
  42  */
  43 class izip_session : public classbase
  44 {
  45  public:
  46         z_stream c_stream;      /* compression stream */
  47         z_stream d_stream;      /* uncompress stream */
  48         izip_status status;     /* Connection status */
  49         std::string outbuf;     /* Holds output buffer (compressed) */
  50         std::string inbuf;      /* Holds input buffer (compressed) */
  51 };
  52
  53 class ModuleZLib : public Module
  54 {
  55         izip_session* sessions;
  56
  57         /* Used for stats z extensions */
  58         float total_out_compressed;
  59         float total_in_compressed;
  60         float total_out_uncompressed;
  61         float total_in_uncompressed;
  62
  63         /* Used for reading data from the wire.
  64          * We need a smaller buffer than CHUNK, else we could read more data
  65          * from the wire than we can pass to the socket code.
  66          */
  67         char *read_buffer;
  68         unsigned int read_buffer_size;
  69  public:
  70
  71         ModuleZLib(InspIRCd* Me)
  72                 : Module::Module(Me)
  73         {
  74                 ServerInstance->Modules->PublishInterface("BufferedSocketHook", this);
  75
  76                 sessions = new izip_session[ServerInstance->SE->GetMaxFds()];
  77                 for (int i = 0; i < ServerInstance->SE->GetMaxFds(); i++)
  78                         sessions[i].status = IZIP_CLOSED;
  79
  80                 total_out_compressed = total_in_compressed = 0;
  81                 total_out_uncompressed = total_in_uncompressed = 0;
  82                 Implementation eventlist[] = { I_OnRawSocketConnect, I_OnRawSocketAccept, I_OnRawSocketClose, I_OnRawSocketRead, I_OnRawSocketWrite, I_OnStats, I_OnRequest };
  83                 ServerInstance->Modules->Attach(eventlist, this, 7);
  84
  85                 read_buffer_size = ServerInstance->Config->NetBufferSize / 4;
  86                 read_buffer = new char[read_buffer_size];
  87         }
  88
  89         virtual ~ModuleZLib()
  90         {
  91                 ServerInstance->Modules->UnpublishInterface("BufferedSocketHook", this);
  92                 delete[] sessions;
  93                 delete[] read_buffer;
  94         }
  95
  96         virtual Version GetVersion()
  97         {
  98                 return Version("$Id$", VF_VENDOR, API_VERSION);
  99         }
 100
 101
 102         /* Handle BufferedSocketHook API requests */
 103         virtual const char* OnRequest(Request* request)
 104         {
 105                 ISHRequest* ISR = (ISHRequest*)request;
 106                 if (strcmp("IS_NAME", request->GetId()) == 0)
 107                 {
 108                         /* Return name */
 109                         return "zip";
 110                 }
 111                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 112                 {
 113                         /* Attach to an inspsocket */
 114                         const char* ret = "OK";
 115                         try
 116                         {
 117                                 ret = ServerInstance->Config->AddIOHook((Module*)this, (BufferedSocket*)ISR->Sock) ? "OK" : NULL;
 118                         }
 119                         catch (ModuleException& e)
 120                         {
 121                                 return NULL;
 122                         }
 123                         return ret;
 124                 }
 125                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 126                 {
 127                         /* Detach from an inspsocket */
 128                         return ServerInstance->Config->DelIOHook((BufferedSocket*)ISR->Sock) ? "OK" : NULL;
 129                 }
 130                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 131                 {
 132                         /* Check for completion of handshake
 133                          * (actually, this module doesnt handshake)
 134                          */
 135                         return "OK";
 136                 }
 137                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 138                 {
 139                         /* Attach certificate data to the inspsocket
 140                          * (this module doesnt do that, either)
 141                          */
 142                         return NULL;
 143                 }
 144                 return NULL;
 145         }
 146
 147         /* Handle stats z (misc stats) */
 148         virtual int OnStats(char symbol, User* user, string_list &results)
 149         {
 150                 if (symbol == 'z')
 151                 {
 152                         std::string sn = ServerInstance->Config->ServerName;
 153
 154                         /* Yeah yeah, i know, floats are ew.
 155                          * We used them here because we'd be casting to float anyway to do this maths,
 156                          * and also only floating point numbers can deal with the pretty large numbers
 157                          * involved in the total throughput of a server over a large period of time.
 158                          * (we dont count 64 bit ints because not all systems have 64 bit ints, and floats
 159                          * can still hold more.
 160                          */
 161                         float outbound_r = (total_out_compressed / (total_out_uncompressed + 0.001)) * 100;
 162                         float inbound_r = (total_in_compressed / (total_in_uncompressed + 0.001)) * 100;
 163
 164                         float total_compressed = total_in_compressed + total_out_compressed;
 165                         float total_uncompressed = total_in_uncompressed + total_out_uncompressed;
 166
 167                         float total_r = (total_compressed / (total_uncompressed + 0.001)) * 100;
 168
 169                         char outbound_ratio[MAXBUF], inbound_ratio[MAXBUF], combined_ratio[MAXBUF];
 170
 171                         sprintf(outbound_ratio, "%3.2f%%", outbound_r);
 172                         sprintf(inbound_ratio, "%3.2f%%", inbound_r);
 173                         sprintf(combined_ratio, "%3.2f%%", total_r);
 174
 175                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_compressed   = "+ConvToStr(total_out_compressed));
 176                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_compressed    = "+ConvToStr(total_in_compressed));
 177                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_uncompressed = "+ConvToStr(total_out_uncompressed));
 178                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_uncompressed  = "+ConvToStr(total_in_uncompressed));
 179                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_ratio        = "+outbound_ratio);
 180                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_ratio         = "+inbound_ratio);
 181                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS combined_ratio        = "+combined_ratio);
 182                         return 0;
 183                 }
 184
 185                 return 0;
 186         }
 187
 188         virtual void OnRawSocketConnect(int fd)
 189         {
 190                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 191                         return;
 192
 193                 izip_session* session = &sessions[fd];
 194
 195                 /* allocate state and buffers */
 196                 session->status = IZIP_OPEN;
 197
 198                 /* Just in case... */
 199                 session->outbuf.clear();
 200
 201                 session->c_stream.zalloc = (alloc_func)0;
 202                 session->c_stream.zfree = (free_func)0;
 203                 session->c_stream.opaque = (voidpf)0;
 204
 205                 session->d_stream.zalloc = (alloc_func)0;
 206                 session->d_stream.zfree = (free_func)0;
 207                 session->d_stream.opaque = (voidpf)0;
 208
 209                 /* If we cant call this, well, we're boned. */
 210                 if (inflateInit(&session->d_stream) != Z_OK)
 211                 {
 212                         session->status = IZIP_CLOSED;
 213                         return;
 214                 }
 215
 216                 /* Same here */
 217                 if (deflateInit(&session->c_stream, Z_BEST_COMPRESSION) != Z_OK)
 218                 {
 219                         inflateEnd(&session->d_stream);
 220                         session->status = IZIP_CLOSED;
 221                         return;
 222                 }
 223         }
 224
 225         virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
 226         {
 227                 /* Nothing special needs doing here compared to connect() */
 228                 OnRawSocketConnect(fd);
 229         }
 230
 231         virtual void OnRawSocketClose(int fd)
 232         {
 233                 CloseSession(&sessions[fd]);
 234         }
 235
 236         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 237         {
 238                 /* Find the sockets session */
 239                 izip_session* session = &sessions[fd];
 240
 241                 if (session->status == IZIP_CLOSED)
 242                         return 0;
 243
 244                 /* Read read_buffer_size bytes at a time to the buffer (usually 128k) */
 245                 readresult = read(fd, read_buffer, read_buffer_size);
 246
 247                 /* Did we get anything? */
 248                 if (readresult <= 0)
 249                         return 0;
 250
 251                 total_in_compressed += readresult;
 252
 253                 /* Copy the compressed data into out input buffer */
 254                 session->inbuf.append(read_buffer, readresult);
 255                 size_t in_len = session->inbuf.length();
 256
 257                 /* Prepare decompression */
 258                 session->d_stream.next_in = (Bytef *)session->inbuf.c_str();
 259                 session->d_stream.avail_in = in_len;
 260
 261                 session->d_stream.next_out = (Bytef*)buffer;
 262                 /* Last byte is reserved for NULL terminating that beast */
 263                 session->d_stream.avail_out = count - 1;
 264
 265                 /* Z_SYNC_FLUSH: Do as much as possible */
 266                 int ret = inflate(&session->d_stream, Z_SYNC_FLUSH);
 267                 /* TODO CloseStream() in here at random places */
 268                 switch (ret)
 269                 {
 270                         case Z_NEED_DICT:
 271                         case Z_STREAM_ERROR:
 272                                 /* This is one of the 'not supposed to happen' things.
 273                                  * Memory corruption, anyone?
 274                                  */
 275                                 Error(session, "General Error. This is not supposed to happen :/");
 276                                 break;
 277                         case Z_DATA_ERROR:
 278                                 Error(session, "Decompression failed, malformed data");
 279                                 break;
 280                         case Z_MEM_ERROR:
 281                                 Error(session, "Out of memory");
 282                                 break;
 283                         case Z_BUF_ERROR:
 284                                 /* This one is non-fatal, buffer is just full
 285                                  * (can't happen here).
 286                                  */
 287                                 Error(session, "Internal error. This is not supposed to happen.");
 288                                 break;
 289                         case Z_STREAM_END:
 290                                 /* This module *never* generates these :/ */
 291                                 Error(session, "End-of-stream marker received");
 292                                 break;
 293                         case Z_OK:
 294                                 break;
 295                         default:
 296                                 /* NO WAI! This can't happen. All errors are handled above. */
 297                                 Error(session, "Unknown error");
 298                                 break;
 299                 }
 300                 if (ret != Z_OK)
 301                 {
 302                         readresult = 0;
 303                         return 0;
 304                 }
 305
 306                 /* Update the inbut buffer */
 307                 unsigned int input_compressed = in_len - session->d_stream.avail_in;
 308                 session->inbuf = session->inbuf.substr(input_compressed);
 309
 310                 /* Update counters (Old size - new size) */
 311                 unsigned int uncompressed_length = (count - 1) - session->d_stream.avail_out;
 312                 total_in_uncompressed += uncompressed_length;
 313
 314                 /* Null-terminate the buffer -- this doesnt harm binary data */
 315                 buffer[uncompressed_length] = 0;
 316
 317                 /* Set the read size to the correct total size */
 318                 readresult = uncompressed_length;
 319
 320                 return 1;
 321         }
 322
 323         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 324         {
 325                 izip_session* session = &sessions[fd];
 326
 327                 if (!count)     /* Nothing to do! */
 328                         return 0;
 329
 330                 if(session->status != IZIP_OPEN)
 331                         /* Seriously, wtf? */
 332                         return 0;
 333
 334                 unsigned char compr[CHUNK];
 335                 int ret;
 336
 337                 /* This loop is really only supposed to run once, but in case 'compr'
 338                  * is filled up somehow we are prepared to handle this situation.
 339                  */
 340                 unsigned int offset = 0;
 341                 do
 342                 {
 343                         /* Prepare compression */
 344                         session->c_stream.next_in = (Bytef*)buffer + offset;
 345                         session->c_stream.avail_in = count - offset;
 346
 347                         session->c_stream.next_out = compr;
 348                         session->c_stream.avail_out = CHUNK;
 349
 350                         /* Compress the text */
 351                         ret = deflate(&session->c_stream, Z_SYNC_FLUSH);
 352                         /* TODO CloseStream() in here at random places */
 353                         switch (ret)
 354                         {
 355                                 case Z_OK:
 356                                         break;
 357                                 case Z_BUF_ERROR:
 358                                         /* This one is non-fatal, buffer is just full
 359                                          * (can't happen here).
 360                                          */
 361                                         Error(session, "Internal error. This is not supposed to happen.");
 362                                         break;
 363                                 case Z_STREAM_ERROR:
 364                                         /* This is one of the 'not supposed to happen' things.
 365                                          * Memory corruption, anyone?
 366                                          */
 367                                         Error(session, "General Error. This is also not supposed to happen.");
 368                                         break;
 369                                 default:
 370                                         Error(session, "Unknown error");
 371                                         break;
 372                         }
 373
 374                         if (ret != Z_OK)
 375                                 return 0;
 376
 377                         /* Space before - space after stuff was added to this */
 378                         unsigned int compressed = CHUNK - session->c_stream.avail_out;
 379                         unsigned int uncompressed = count - session->c_stream.avail_in;
 380
 381                         /* Make it skip the data which was compressed already */
 382                         offset += uncompressed;
 383
 384                         /* Update stats */
 385                         total_out_uncompressed += uncompressed;
 386                         total_out_compressed += compressed;
 387
 388                         /* Add compressed to the output buffer */
 389                         session->outbuf.append((const char*)compr, compressed);
 390                 } while (session->c_stream.avail_in != 0);
 391
 392                 /* Lets see how much we can send out */
 393                 ret = write(fd, session->outbuf.data(), session->outbuf.length());
 394
 395                 /* Check for errors, and advance the buffer if any was sent */
 396                 if (ret > 0)
 397                         session->outbuf = session->outbuf.substr(ret);
 398                 else if (ret < 1)
 399                 {
 400                         if (errno == EAGAIN)
 401                                 return 0;
 402                         else
 403                         {
 404                                 session->outbuf.clear();
 405                                 /* TODO pass errors down? */
 406                                 return 0;
 407                         }
 408                 }
 409
 410                 /* ALL LIES the lot of it, we havent really written
 411                  * this amount, but the layer above doesnt need to know.
 412                  */
 413                 return count;
 414         }
 415
 416         void Error(izip_session* session, const std::string &text)
 417         {
 418                 ServerInstance->SNO->WriteToSnoMask('l', "ziplink error: " + text);
 419         }
 420
 421         void CloseSession(izip_session* session)
 422         {
 423                 if (session->status == IZIP_OPEN)
 424                 {
 425                         session->status = IZIP_CLOSED;
 426                         session->outbuf.clear();
 427                         inflateEnd(&session->d_stream);
 428                         deflateEnd(&session->c_stream);
 429                 }
 430         }
 431
 432 };
 433
 434 MODULE_INIT(ModuleZLib)
 435