src/modules/extra/m_ziplink.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2009 InspIRCd Development Team
   6  * See: http://wiki.inspircd.org/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 <iostream>
  17
  18 /* $ModDesc: Provides zlib link support for servers */
  19 /* $LinkerFlags: -lz */
  20
  21 /*
  22  * ZLIB_BEST_COMPRESSION (9) is used for all sending of data with
  23  * a flush after each chunk. A frame may contain multiple lines
  24  * and should be treated as raw binary data.
  25  */
  26
  27 /* Status of a connection */
  28 enum izip_status { IZIP_CLOSED = 0, IZIP_OPEN };
  29
  30 /** Represents an zipped connections extra data
  31  */
  32 class izip_session
  33 {
  34  public:
  35         z_stream c_stream;      /* compression stream */
  36         z_stream d_stream;      /* uncompress stream */
  37         izip_status status;     /* Connection status */
  38         std::string outbuf;     /* Holds output buffer (compressed) */
  39         std::string inbuf;      /* Holds input buffer (compressed) */
  40 };
  41
  42 class ModuleZLib : public Module
  43 {
  44         izip_session* sessions;
  45
  46         /* Used for stats z extensions */
  47         float total_out_compressed;
  48         float total_in_compressed;
  49         float total_out_uncompressed;
  50         float total_in_uncompressed;
  51
  52         /* Used for reading data from the wire and compressing data to. */
  53         char *net_buffer;
  54         unsigned int net_buffer_size;
  55  public:
  56
  57         ModuleZLib()
  58         {
  59                 ServerInstance->Modules->PublishInterface("BufferedSocketHook", this);
  60
  61                 sessions = new izip_session[ServerInstance->SE->GetMaxFds()];
  62                 for (int i = 0; i < ServerInstance->SE->GetMaxFds(); i++)
  63                         sessions[i].status = IZIP_CLOSED;
  64
  65                 total_out_compressed = total_in_compressed = 0;
  66                 total_out_uncompressed = total_in_uncompressed = 0;
  67                 Implementation eventlist[] = { I_OnStats };
  68                 ServerInstance->Modules->Attach(eventlist, this, 1);
  69
  70                 // Allocate a buffer which is used for reading and writing data
  71                 net_buffer_size = ServerInstance->Config->NetBufferSize;
  72                 net_buffer = new char[net_buffer_size];
  73         }
  74
  75         ~ModuleZLib()
  76         {
  77                 ServerInstance->Modules->UnpublishInterface("BufferedSocketHook", this);
  78                 delete[] sessions;
  79                 delete[] net_buffer;
  80         }
  81
  82         Version GetVersion()
  83         {
  84                 return Version("Provides zlib link support for servers", VF_VENDOR);
  85         }
  86
  87         /* Handle stats z (misc stats) */
  88         ModResult OnStats(char symbol, User* user, string_list &results)
  89         {
  90                 if (symbol == 'z')
  91                 {
  92                         std::string sn = ServerInstance->Config->ServerName;
  93
  94                         /* Yeah yeah, i know, floats are ew.
  95                          * We used them here because we'd be casting to float anyway to do this maths,
  96                          * and also only floating point numbers can deal with the pretty large numbers
  97                          * involved in the total throughput of a server over a large period of time.
  98                          * (we dont count 64 bit ints because not all systems have 64 bit ints, and floats
  99                          * can still hold more.
 100                          */
 101                         float outbound_r = (total_out_compressed / (total_out_uncompressed + 0.001)) * 100;
 102                         float inbound_r = (total_in_compressed / (total_in_uncompressed + 0.001)) * 100;
 103
 104                         float total_compressed = total_in_compressed + total_out_compressed;
 105                         float total_uncompressed = total_in_uncompressed + total_out_uncompressed;
 106
 107                         float total_r = (total_compressed / (total_uncompressed + 0.001)) * 100;
 108
 109                         char outbound_ratio[MAXBUF], inbound_ratio[MAXBUF], combined_ratio[MAXBUF];
 110
 111                         sprintf(outbound_ratio, "%3.2f%%", outbound_r);
 112                         sprintf(inbound_ratio, "%3.2f%%", inbound_r);
 113                         sprintf(combined_ratio, "%3.2f%%", total_r);
 114
 115                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_compressed   = "+ConvToStr(total_out_compressed));
 116                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_compressed    = "+ConvToStr(total_in_compressed));
 117                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_uncompressed = "+ConvToStr(total_out_uncompressed));
 118                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_uncompressed  = "+ConvToStr(total_in_uncompressed));
 119                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS percentage_of_original_outbound_traffic        = "+outbound_ratio);
 120                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS percentage_of_orignal_inbound_traffic         = "+inbound_ratio);
 121                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS total_size_of_original_traffic        = "+combined_ratio);
 122                         return MOD_RES_PASSTHRU;
 123                 }
 124
 125                 return MOD_RES_PASSTHRU;
 126         }
 127
 128         void OnStreamSocketConnect(StreamSocket* user)
 129         {
 130                 OnStreamSocketAccept(user, 0, 0);
 131         }
 132
 133         void OnRawSocketAccept(StreamSocket* user, irc::sockets::sockaddrs*, irc::sockets::sockaddrs*)
 134         {
 135                 int fd = user->GetFd();
 136
 137                 izip_session* session = &sessions[fd];
 138
 139                 /* Just in case... */
 140                 session->outbuf.clear();
 141
 142                 session->c_stream.zalloc = (alloc_func)0;
 143                 session->c_stream.zfree = (free_func)0;
 144                 session->c_stream.opaque = (voidpf)0;
 145
 146                 session->d_stream.zalloc = (alloc_func)0;
 147                 session->d_stream.zfree = (free_func)0;
 148                 session->d_stream.opaque = (voidpf)0;
 149
 150                 /* If we cant call this, well, we're boned. */
 151                 if (inflateInit(&session->d_stream) != Z_OK)
 152                 {
 153                         session->status = IZIP_CLOSED;
 154                         return;
 155                 }
 156
 157                 /* Same here */
 158                 if (deflateInit(&session->c_stream, Z_BEST_COMPRESSION) != Z_OK)
 159                 {
 160                         inflateEnd(&session->d_stream);
 161                         session->status = IZIP_CLOSED;
 162                         return;
 163                 }
 164
 165                 /* Just in case, do this last */
 166                 session->status = IZIP_OPEN;
 167         }
 168
 169         void OnStreamSocketClose(StreamSocket* user)
 170         {
 171                 int fd = user->GetFd();
 172                 CloseSession(&sessions[fd]);
 173         }
 174
 175         int OnStreamSocketRead(StreamSocket* user, std::string& recvq)
 176         {
 177                 int fd = user->GetFd();
 178                 /* Find the sockets session */
 179                 izip_session* session = &sessions[fd];
 180
 181                 if (session->status == IZIP_CLOSED)
 182                         return -1;
 183
 184                 if (session->inbuf.empty())
 185                 {
 186                         /* Read read_buffer_size bytes at a time to the buffer (usually 2.5k) */
 187                         int readresult = read(fd, net_buffer, net_buffer_size);
 188
 189                         if (readresult < 0)
 190                         {
 191                                 if (errno == EINTR || errno == EAGAIN)
 192                                         return 0;
 193                         }
 194                         if (readresult <= 0)
 195                                 return -1;
 196
 197                         total_in_compressed += readresult;
 198
 199                         /* Copy the compressed data into our input buffer */
 200                         session->inbuf.append(net_buffer, readresult);
 201                 }
 202
 203                 size_t in_len = session->inbuf.length();
 204                 char* buffer = ServerInstance->GetReadBuffer();
 205                 int count = ServerInstance->Config->NetBufferSize;
 206
 207                 /* Prepare decompression */
 208                 session->d_stream.next_in = (Bytef *)session->inbuf.c_str();
 209                 session->d_stream.avail_in = in_len;
 210
 211                 session->d_stream.next_out = (Bytef*)buffer;
 212                 /* Last byte is reserved for NULL terminating that beast */
 213                 session->d_stream.avail_out = count - 1;
 214
 215                 /* Z_SYNC_FLUSH: Do as much as possible */
 216                 int ret = inflate(&session->d_stream, Z_SYNC_FLUSH);
 217                 /* TODO CloseStream() in here at random places */
 218                 switch (ret)
 219                 {
 220                         case Z_NEED_DICT:
 221                         case Z_STREAM_ERROR:
 222                                 /* This is one of the 'not supposed to happen' things.
 223                                  * Memory corruption, anyone?
 224                                  */
 225                                 Error(session, "General Error. This is not supposed to happen :/");
 226                                 break;
 227                         case Z_DATA_ERROR:
 228                                 Error(session, "Decompression failed, malformed data");
 229                                 break;
 230                         case Z_MEM_ERROR:
 231                                 Error(session, "Out of memory");
 232                                 break;
 233                         case Z_BUF_ERROR:
 234                                 /* This one is non-fatal, buffer is just full
 235                                  * (can't happen here).
 236                                  */
 237                                 Error(session, "Internal error. This is not supposed to happen.");
 238                                 break;
 239                         case Z_STREAM_END:
 240                                 /* This module *never* generates these :/ */
 241                                 Error(session, "End-of-stream marker received");
 242                                 break;
 243                         case Z_OK:
 244                                 break;
 245                         default:
 246                                 /* NO WAI! This can't happen. All errors are handled above. */
 247                                 Error(session, "Unknown error");
 248                                 break;
 249                 }
 250                 if (ret != Z_OK)
 251                 {
 252                         return -1;
 253                 }
 254
 255                 /* Update the inbut buffer */
 256                 unsigned int input_compressed = in_len - session->d_stream.avail_in;
 257                 session->inbuf = session->inbuf.substr(input_compressed);
 258
 259                 /* Update counters (Old size - new size) */
 260                 unsigned int uncompressed_length = (count - 1) - session->d_stream.avail_out;
 261                 total_in_uncompressed += uncompressed_length;
 262
 263                 /* Null-terminate the buffer -- this doesnt harm binary data */
 264                 recvq.append(buffer, uncompressed_length);
 265                 return 1;
 266         }
 267
 268         int OnStreamSocketWrite(StreamSocket* user, std::string& sendq)
 269         {
 270                 int fd = user->GetFd();
 271                 izip_session* session = &sessions[fd];
 272
 273                 if(session->status != IZIP_OPEN)
 274                         /* Seriously, wtf? */
 275                         return -1;
 276
 277                 int ret;
 278
 279                 /* This loop is really only supposed to run once, but in case 'compr'
 280                  * is filled up somehow we are prepared to handle this situation.
 281                  */
 282                 unsigned int offset = 0;
 283                 do
 284                 {
 285                         /* Prepare compression */
 286                         session->c_stream.next_in = (Bytef*)sendq.data() + offset;
 287                         session->c_stream.avail_in = sendq.length() - offset;
 288
 289                         session->c_stream.next_out = (Bytef*)net_buffer;
 290                         session->c_stream.avail_out = net_buffer_size;
 291
 292                         /* Compress the text */
 293                         ret = deflate(&session->c_stream, Z_SYNC_FLUSH);
 294                         /* TODO CloseStream() in here at random places */
 295                         switch (ret)
 296                         {
 297                                 case Z_OK:
 298                                         break;
 299                                 case Z_BUF_ERROR:
 300                                         /* This one is non-fatal, buffer is just full
 301                                          * (can't happen here).
 302                                          */
 303                                         Error(session, "Internal error. This is not supposed to happen.");
 304                                         break;
 305                                 case Z_STREAM_ERROR:
 306                                         /* This is one of the 'not supposed to happen' things.
 307                                          * Memory corruption, anyone?
 308                                          */
 309                                         Error(session, "General Error. This is also not supposed to happen.");
 310                                         break;
 311                                 default:
 312                                         Error(session, "Unknown error");
 313                                         break;
 314                         }
 315
 316                         if (ret != Z_OK)
 317                                 return 0;
 318
 319                         /* Space before - space after stuff was added to this */
 320                         unsigned int compressed = net_buffer_size - session->c_stream.avail_out;
 321                         unsigned int uncompressed = sendq.length() - session->c_stream.avail_in;
 322
 323                         /* Make it skip the data which was compressed already */
 324                         offset += uncompressed;
 325
 326                         /* Update stats */
 327                         total_out_uncompressed += uncompressed;
 328                         total_out_compressed += compressed;
 329
 330                         /* Add compressed to the output buffer */
 331                         session->outbuf.append((const char*)net_buffer, compressed);
 332                 } while (session->c_stream.avail_in != 0);
 333
 334                 /* Lets see how much we can send out */
 335                 ret = write(fd, session->outbuf.data(), session->outbuf.length());
 336
 337                 /* Check for errors, and advance the buffer if any was sent */
 338                 if (ret > 0)
 339                         session->outbuf = session->outbuf.substr(ret);
 340                 else if (ret < 1)
 341                 {
 342                         if (errno == EAGAIN)
 343                                 return 0;
 344                         else
 345                         {
 346                                 session->outbuf.clear();
 347                                 return -1;
 348                         }
 349                 }
 350
 351                 return 1;
 352         }
 353
 354         void Error(izip_session* session, const std::string &text)
 355         {
 356                 ServerInstance->SNO->WriteToSnoMask('l', "ziplink error: " + text);
 357         }
 358
 359         void CloseSession(izip_session* session)
 360         {
 361                 if (session->status == IZIP_OPEN)
 362                 {
 363                         session->status = IZIP_CLOSED;
 364                         session->outbuf.clear();
 365                         inflateEnd(&session->d_stream);
 366                         deflateEnd(&session->c_stream);
 367                 }
 368         }
 369
 370 };
 371
 372 MODULE_INIT(ModuleZLib)
 373