src/modules/extra/m_ziplink.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2010 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                 sessions = new izip_session[ServerInstance->SE->GetMaxFds()];
  60                 for (int i = 0; i < ServerInstance->SE->GetMaxFds(); i++)
  61                         sessions[i].status = IZIP_CLOSED;
  62
  63                 total_out_compressed = total_in_compressed = 0;
  64                 total_out_uncompressed = total_in_uncompressed = 0;
  65                 Implementation eventlist[] = { I_OnStats };
  66                 ServerInstance->Modules->Attach(eventlist, this, 1);
  67
  68                 // Allocate a buffer which is used for reading and writing data
  69                 net_buffer_size = ServerInstance->Config->NetBufferSize;
  70                 net_buffer = new char[net_buffer_size];
  71         }
  72
  73         ~ModuleZLib()
  74         {
  75                 delete[] sessions;
  76                 delete[] net_buffer;
  77         }
  78
  79         Version GetVersion()
  80         {
  81                 return Version("Provides zlib link support for servers", VF_VENDOR);
  82         }
  83
  84         /* Handle stats z (misc stats) */
  85         ModResult OnStats(char symbol, User* user, string_list &results)
  86         {
  87                 if (symbol == 'z')
  88                 {
  89                         std::string sn = ServerInstance->Config->ServerName;
  90
  91                         /* Yeah yeah, i know, floats are ew.
  92                          * We used them here because we'd be casting to float anyway to do this maths,
  93                          * and also only floating point numbers can deal with the pretty large numbers
  94                          * involved in the total throughput of a server over a large period of time.
  95                          * (we dont count 64 bit ints because not all systems have 64 bit ints, and floats
  96                          * can still hold more.
  97                          */
  98                         float outbound_r = (total_out_compressed / (total_out_uncompressed + 0.001)) * 100;
  99                         float inbound_r = (total_in_compressed / (total_in_uncompressed + 0.001)) * 100;
 100
 101                         float total_compressed = total_in_compressed + total_out_compressed;
 102                         float total_uncompressed = total_in_uncompressed + total_out_uncompressed;
 103
 104                         float total_r = (total_compressed / (total_uncompressed + 0.001)) * 100;
 105
 106                         char outbound_ratio[MAXBUF], inbound_ratio[MAXBUF], combined_ratio[MAXBUF];
 107
 108                         sprintf(outbound_ratio, "%3.2f%%", outbound_r);
 109                         sprintf(inbound_ratio, "%3.2f%%", inbound_r);
 110                         sprintf(combined_ratio, "%3.2f%%", total_r);
 111
 112                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_compressed   = "+ConvToStr(total_out_compressed));
 113                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_compressed    = "+ConvToStr(total_in_compressed));
 114                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_uncompressed = "+ConvToStr(total_out_uncompressed));
 115                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_uncompressed  = "+ConvToStr(total_in_uncompressed));
 116                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS percentage_of_original_outbound_traffic        = "+outbound_ratio);
 117                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS percentage_of_orignal_inbound_traffic         = "+inbound_ratio);
 118                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS total_size_of_original_traffic        = "+combined_ratio);
 119                         return MOD_RES_PASSTHRU;
 120                 }
 121
 122                 return MOD_RES_PASSTHRU;
 123         }
 124
 125         void OnStreamSocketConnect(StreamSocket* user)
 126         {
 127                 OnStreamSocketAccept(user, 0, 0);
 128         }
 129
 130         void OnRawSocketAccept(StreamSocket* user, irc::sockets::sockaddrs*, irc::sockets::sockaddrs*)
 131         {
 132                 int fd = user->GetFd();
 133
 134                 izip_session* session = &sessions[fd];
 135
 136                 /* Just in case... */
 137                 session->outbuf.clear();
 138
 139                 session->c_stream.zalloc = (alloc_func)0;
 140                 session->c_stream.zfree = (free_func)0;
 141                 session->c_stream.opaque = (voidpf)0;
 142
 143                 session->d_stream.zalloc = (alloc_func)0;
 144                 session->d_stream.zfree = (free_func)0;
 145                 session->d_stream.opaque = (voidpf)0;
 146
 147                 /* If we cant call this, well, we're boned. */
 148                 if (inflateInit(&session->d_stream) != Z_OK)
 149                 {
 150                         session->status = IZIP_CLOSED;
 151                         return;
 152                 }
 153
 154                 /* Same here */
 155                 if (deflateInit(&session->c_stream, Z_BEST_COMPRESSION) != Z_OK)
 156                 {
 157                         inflateEnd(&session->d_stream);
 158                         session->status = IZIP_CLOSED;
 159                         return;
 160                 }
 161
 162                 /* Just in case, do this last */
 163                 session->status = IZIP_OPEN;
 164         }
 165
 166         void OnStreamSocketClose(StreamSocket* user)
 167         {
 168                 int fd = user->GetFd();
 169                 CloseSession(&sessions[fd]);
 170         }
 171
 172         int OnStreamSocketRead(StreamSocket* user, std::string& recvq)
 173         {
 174                 int fd = user->GetFd();
 175                 /* Find the sockets session */
 176                 izip_session* session = &sessions[fd];
 177
 178                 if (session->status == IZIP_CLOSED)
 179                         return -1;
 180
 181                 if (session->inbuf.empty())
 182                 {
 183                         /* Read read_buffer_size bytes at a time to the buffer (usually 2.5k) */
 184                         int readresult = read(fd, net_buffer, net_buffer_size);
 185
 186                         if (readresult < 0)
 187                         {
 188                                 if (errno == EINTR || errno == EAGAIN)
 189                                         return 0;
 190                         }
 191                         if (readresult <= 0)
 192                                 return -1;
 193
 194                         total_in_compressed += readresult;
 195
 196                         /* Copy the compressed data into our input buffer */
 197                         session->inbuf.append(net_buffer, readresult);
 198                 }
 199
 200                 size_t in_len = session->inbuf.length();
 201                 char* buffer = ServerInstance->GetReadBuffer();
 202                 int count = ServerInstance->Config->NetBufferSize;
 203
 204                 /* Prepare decompression */
 205                 session->d_stream.next_in = (Bytef *)session->inbuf.c_str();
 206                 session->d_stream.avail_in = in_len;
 207
 208                 session->d_stream.next_out = (Bytef*)buffer;
 209                 /* Last byte is reserved for NULL terminating that beast */
 210                 session->d_stream.avail_out = count - 1;
 211
 212                 /* Z_SYNC_FLUSH: Do as much as possible */
 213                 int ret = inflate(&session->d_stream, Z_SYNC_FLUSH);
 214                 /* TODO CloseStream() in here at random places */
 215                 switch (ret)
 216                 {
 217                         case Z_NEED_DICT:
 218                         case Z_STREAM_ERROR:
 219                                 /* This is one of the 'not supposed to happen' things.
 220                                  * Memory corruption, anyone?
 221                                  */
 222                                 Error(session, "General Error. This is not supposed to happen :/");
 223                                 break;
 224                         case Z_DATA_ERROR:
 225                                 Error(session, "Decompression failed, malformed data");
 226                                 break;
 227                         case Z_MEM_ERROR:
 228                                 Error(session, "Out of memory");
 229                                 break;
 230                         case Z_BUF_ERROR:
 231                                 /* This one is non-fatal, buffer is just full
 232                                  * (can't happen here).
 233                                  */
 234                                 Error(session, "Internal error. This is not supposed to happen.");
 235                                 break;
 236                         case Z_STREAM_END:
 237                                 /* This module *never* generates these :/ */
 238                                 Error(session, "End-of-stream marker received");
 239                                 break;
 240                         case Z_OK:
 241                                 break;
 242                         default:
 243                                 /* NO WAI! This can't happen. All errors are handled above. */
 244                                 Error(session, "Unknown error");
 245                                 break;
 246                 }
 247                 if (ret != Z_OK)
 248                 {
 249                         return -1;
 250                 }
 251
 252                 /* Update the inbut buffer */
 253                 unsigned int input_compressed = in_len - session->d_stream.avail_in;
 254                 session->inbuf = session->inbuf.substr(input_compressed);
 255
 256                 /* Update counters (Old size - new size) */
 257                 unsigned int uncompressed_length = (count - 1) - session->d_stream.avail_out;
 258                 total_in_uncompressed += uncompressed_length;
 259
 260                 /* Null-terminate the buffer -- this doesnt harm binary data */
 261                 recvq.append(buffer, uncompressed_length);
 262                 return 1;
 263         }
 264
 265         int OnStreamSocketWrite(StreamSocket* user, std::string& sendq)
 266         {
 267                 int fd = user->GetFd();
 268                 izip_session* session = &sessions[fd];
 269
 270                 if(session->status != IZIP_OPEN)
 271                         /* Seriously, wtf? */
 272                         return -1;
 273
 274                 int ret;
 275
 276                 /* This loop is really only supposed to run once, but in case 'compr'
 277                  * is filled up somehow we are prepared to handle this situation.
 278                  */
 279                 unsigned int offset = 0;
 280                 do
 281                 {
 282                         /* Prepare compression */
 283                         session->c_stream.next_in = (Bytef*)sendq.data() + offset;
 284                         session->c_stream.avail_in = sendq.length() - offset;
 285
 286                         session->c_stream.next_out = (Bytef*)net_buffer;
 287                         session->c_stream.avail_out = net_buffer_size;
 288
 289                         /* Compress the text */
 290                         ret = deflate(&session->c_stream, Z_SYNC_FLUSH);
 291                         /* TODO CloseStream() in here at random places */
 292                         switch (ret)
 293                         {
 294                                 case Z_OK:
 295                                         break;
 296                                 case Z_BUF_ERROR:
 297                                         /* This one is non-fatal, buffer is just full
 298                                          * (can't happen here).
 299                                          */
 300                                         Error(session, "Internal error. This is not supposed to happen.");
 301                                         break;
 302                                 case Z_STREAM_ERROR:
 303                                         /* This is one of the 'not supposed to happen' things.
 304                                          * Memory corruption, anyone?
 305                                          */
 306                                         Error(session, "General Error. This is also not supposed to happen.");
 307                                         break;
 308                                 default:
 309                                         Error(session, "Unknown error");
 310                                         break;
 311                         }
 312
 313                         if (ret != Z_OK)
 314                                 return 0;
 315
 316                         /* Space before - space after stuff was added to this */
 317                         unsigned int compressed = net_buffer_size - session->c_stream.avail_out;
 318                         unsigned int uncompressed = sendq.length() - session->c_stream.avail_in;
 319
 320                         /* Make it skip the data which was compressed already */
 321                         offset += uncompressed;
 322
 323                         /* Update stats */
 324                         total_out_uncompressed += uncompressed;
 325                         total_out_compressed += compressed;
 326
 327                         /* Add compressed to the output buffer */
 328                         session->outbuf.append((const char*)net_buffer, compressed);
 329                 } while (session->c_stream.avail_in != 0);
 330
 331                 /* Lets see how much we can send out */
 332                 ret = write(fd, session->outbuf.data(), session->outbuf.length());
 333
 334                 /* Check for errors, and advance the buffer if any was sent */
 335                 if (ret > 0)
 336                         session->outbuf = session->outbuf.substr(ret);
 337                 else if (ret < 1)
 338                 {
 339                         if (errno == EAGAIN)
 340                                 return 0;
 341                         else
 342                         {
 343                                 session->outbuf.clear();
 344                                 return -1;
 345                         }
 346                 }
 347
 348                 return 1;
 349         }
 350
 351         void Error(izip_session* session, const std::string &text)
 352         {
 353                 ServerInstance->SNO->WriteToSnoMask('l', "ziplink error: " + text);
 354         }
 355
 356         void CloseSession(izip_session* session)
 357         {
 358                 if (session->status == IZIP_OPEN)
 359                 {
 360                         session->status = IZIP_CLOSED;
 361                         session->outbuf.clear();
 362                         inflateEnd(&session->d_stream);
 363                         deflateEnd(&session->c_stream);
 364                 }
 365         }
 366
 367 };
 368
 369 MODULE_INIT(ModuleZLib)
 370