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 "transport.h"
  17 #include <iostream>
  18
  19 /* $ModDesc: Provides zlib link support for servers */
  20 /* $LinkerFlags: -lz */
  21 /* $ModDep: transport.h */
  22
  23 /*
  24  * ZLIB_BEST_COMPRESSION (9) is used for all sending of data with
  25  * a flush after each chunk. A frame may contain multiple lines
  26  * and should be treated as raw binary data.
  27  */
  28
  29 /* Status of a connection */
  30 enum izip_status { IZIP_CLOSED = 0, IZIP_OPEN };
  31
  32 /** Represents an zipped connections extra data
  33  */
  34 class izip_session : public classbase
  35 {
  36  public:
  37         z_stream c_stream;      /* compression stream */
  38         z_stream d_stream;      /* uncompress stream */
  39         izip_status status;     /* Connection status */
  40         std::string outbuf;     /* Holds output buffer (compressed) */
  41         std::string inbuf;      /* Holds input buffer (compressed) */
  42 };
  43
  44 class ModuleZLib : public Module
  45 {
  46         izip_session* sessions;
  47
  48         /* Used for stats z extensions */
  49         float total_out_compressed;
  50         float total_in_compressed;
  51         float total_out_uncompressed;
  52         float total_in_uncompressed;
  53
  54         /* Used for reading data from the wire and compressing data to. */
  55         char *net_buffer;
  56         unsigned int net_buffer_size;
  57  public:
  58
  59         ModuleZLib()
  60                         {
  61                 ServerInstance->Modules->PublishInterface("BufferedSocketHook", this);
  62
  63                 sessions = new izip_session[ServerInstance->SE->GetMaxFds()];
  64                 for (int i = 0; i < ServerInstance->SE->GetMaxFds(); i++)
  65                         sessions[i].status = IZIP_CLOSED;
  66
  67                 total_out_compressed = total_in_compressed = 0;
  68                 total_out_uncompressed = total_in_uncompressed = 0;
  69                 Implementation eventlist[] = { I_OnStats, I_OnRequest };
  70                 ServerInstance->Modules->Attach(eventlist, this, 2);
  71
  72                 // Allocate a buffer which is used for reading and writing data
  73                 net_buffer_size = ServerInstance->Config->NetBufferSize;
  74                 net_buffer = new char[net_buffer_size];
  75         }
  76
  77         ~ModuleZLib()
  78         {
  79                 ServerInstance->Modules->UnpublishInterface("BufferedSocketHook", this);
  80                 delete[] sessions;
  81                 delete[] net_buffer;
  82         }
  83
  84         Version GetVersion()
  85         {
  86                 return Version("Provides zlib link support for servers", VF_VENDOR, API_VERSION);
  87         }
  88
  89
  90         /* Handle BufferedSocketHook API requests */
  91         const char* OnRequest(Request* request)
  92         {
  93                 ISHRequest* ISR = (ISHRequest*)request;
  94                 if (strcmp("IS_NAME", request->GetId()) == 0)
  95                 {
  96                         /* Return name */
  97                         return "zip";
  98                 }
  99                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 100                 {
 101                         ISR->Sock->AddIOHook(this);
 102                         return "OK";
 103                 }
 104                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 105                 {
 106                         ISR->Sock->DelIOHook();
 107                         return "OK";
 108                 }
 109                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 110                 {
 111                         /* Check for completion of handshake
 112                          * (actually, this module doesnt handshake)
 113                          */
 114                         return "OK";
 115                 }
 116                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 117                 {
 118                         /* Attach certificate data to the inspsocket
 119                          * (this module doesnt do that, either)
 120                          */
 121                         return NULL;
 122                 }
 123                 return NULL;
 124         }
 125
 126         /* Handle stats z (misc stats) */
 127         ModResult OnStats(char symbol, User* user, string_list &results)
 128         {
 129                 if (symbol == 'z')
 130                 {
 131                         std::string sn = ServerInstance->Config->ServerName;
 132
 133                         /* Yeah yeah, i know, floats are ew.
 134                          * We used them here because we'd be casting to float anyway to do this maths,
 135                          * and also only floating point numbers can deal with the pretty large numbers
 136                          * involved in the total throughput of a server over a large period of time.
 137                          * (we dont count 64 bit ints because not all systems have 64 bit ints, and floats
 138                          * can still hold more.
 139                          */
 140                         float outbound_r = (total_out_compressed / (total_out_uncompressed + 0.001)) * 100;
 141                         float inbound_r = (total_in_compressed / (total_in_uncompressed + 0.001)) * 100;
 142
 143                         float total_compressed = total_in_compressed + total_out_compressed;
 144                         float total_uncompressed = total_in_uncompressed + total_out_uncompressed;
 145
 146                         float total_r = (total_compressed / (total_uncompressed + 0.001)) * 100;
 147
 148                         char outbound_ratio[MAXBUF], inbound_ratio[MAXBUF], combined_ratio[MAXBUF];
 149
 150                         sprintf(outbound_ratio, "%3.2f%%", outbound_r);
 151                         sprintf(inbound_ratio, "%3.2f%%", inbound_r);
 152                         sprintf(combined_ratio, "%3.2f%%", total_r);
 153
 154                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_compressed   = "+ConvToStr(total_out_compressed));
 155                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_compressed    = "+ConvToStr(total_in_compressed));
 156                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_uncompressed = "+ConvToStr(total_out_uncompressed));
 157                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_uncompressed  = "+ConvToStr(total_in_uncompressed));
 158                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS percentage_of_original_outbound_traffic        = "+outbound_ratio);
 159                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS percentage_of_orignal_inbound_traffic         = "+inbound_ratio);
 160                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS total_size_of_original_traffic        = "+combined_ratio);
 161                         return MOD_RES_PASSTHRU;
 162                 }
 163
 164                 return MOD_RES_PASSTHRU;
 165         }
 166
 167         void OnStreamSocketConnect(StreamSocket* user)
 168         {
 169                 OnStreamSocketAccept(user, 0, 0);
 170         }
 171
 172         void OnRawSocketAccept(StreamSocket* user, irc::sockets::sockaddrs*, irc::sockets::sockaddrs*)
 173         {
 174                 int fd = user->GetFd();
 175
 176                 izip_session* session = &sessions[fd];
 177
 178                 /* Just in case... */
 179                 session->outbuf.clear();
 180
 181                 session->c_stream.zalloc = (alloc_func)0;
 182                 session->c_stream.zfree = (free_func)0;
 183                 session->c_stream.opaque = (voidpf)0;
 184
 185                 session->d_stream.zalloc = (alloc_func)0;
 186                 session->d_stream.zfree = (free_func)0;
 187                 session->d_stream.opaque = (voidpf)0;
 188
 189                 /* If we cant call this, well, we're boned. */
 190                 if (inflateInit(&session->d_stream) != Z_OK)
 191                 {
 192                         session->status = IZIP_CLOSED;
 193                         return;
 194                 }
 195
 196                 /* Same here */
 197                 if (deflateInit(&session->c_stream, Z_BEST_COMPRESSION) != Z_OK)
 198                 {
 199                         inflateEnd(&session->d_stream);
 200                         session->status = IZIP_CLOSED;
 201                         return;
 202                 }
 203
 204                 /* Just in case, do this last */
 205                 session->status = IZIP_OPEN;
 206         }
 207
 208         void OnStreamSocketClose(StreamSocket* user)
 209         {
 210                 int fd = user->GetFd();
 211                 CloseSession(&sessions[fd]);
 212         }
 213
 214         int OnStreamSocketRead(StreamSocket* user, std::string& recvq)
 215         {
 216                 int fd = user->GetFd();
 217                 /* Find the sockets session */
 218                 izip_session* session = &sessions[fd];
 219
 220                 if (session->status == IZIP_CLOSED)
 221                         return -1;
 222
 223                 if (session->inbuf.empty())
 224                 {
 225                         /* Read read_buffer_size bytes at a time to the buffer (usually 2.5k) */
 226                         int readresult = read(fd, net_buffer, net_buffer_size);
 227
 228                         if (readresult < 0)
 229                         {
 230                                 if (errno == EINTR || errno == EAGAIN)
 231                                         return 0;
 232                         }
 233                         if (readresult <= 0)
 234                                 return -1;
 235
 236                         total_in_compressed += readresult;
 237
 238                         /* Copy the compressed data into our input buffer */
 239                         session->inbuf.append(net_buffer, readresult);
 240                 }
 241
 242                 size_t in_len = session->inbuf.length();
 243                 char* buffer = ServerInstance->GetReadBuffer();
 244                 int count = ServerInstance->Config->NetBufferSize;
 245
 246                 /* Prepare decompression */
 247                 session->d_stream.next_in = (Bytef *)session->inbuf.c_str();
 248                 session->d_stream.avail_in = in_len;
 249
 250                 session->d_stream.next_out = (Bytef*)buffer;
 251                 /* Last byte is reserved for NULL terminating that beast */
 252                 session->d_stream.avail_out = count - 1;
 253
 254                 /* Z_SYNC_FLUSH: Do as much as possible */
 255                 int ret = inflate(&session->d_stream, Z_SYNC_FLUSH);
 256                 /* TODO CloseStream() in here at random places */
 257                 switch (ret)
 258                 {
 259                         case Z_NEED_DICT:
 260                         case Z_STREAM_ERROR:
 261                                 /* This is one of the 'not supposed to happen' things.
 262                                  * Memory corruption, anyone?
 263                                  */
 264                                 Error(session, "General Error. This is not supposed to happen :/");
 265                                 break;
 266                         case Z_DATA_ERROR:
 267                                 Error(session, "Decompression failed, malformed data");
 268                                 break;
 269                         case Z_MEM_ERROR:
 270                                 Error(session, "Out of memory");
 271                                 break;
 272                         case Z_BUF_ERROR:
 273                                 /* This one is non-fatal, buffer is just full
 274                                  * (can't happen here).
 275                                  */
 276                                 Error(session, "Internal error. This is not supposed to happen.");
 277                                 break;
 278                         case Z_STREAM_END:
 279                                 /* This module *never* generates these :/ */
 280                                 Error(session, "End-of-stream marker received");
 281                                 break;
 282                         case Z_OK:
 283                                 break;
 284                         default:
 285                                 /* NO WAI! This can't happen. All errors are handled above. */
 286                                 Error(session, "Unknown error");
 287                                 break;
 288                 }
 289                 if (ret != Z_OK)
 290                 {
 291                         return -1;
 292                 }
 293
 294                 /* Update the inbut buffer */
 295                 unsigned int input_compressed = in_len - session->d_stream.avail_in;
 296                 session->inbuf = session->inbuf.substr(input_compressed);
 297
 298                 /* Update counters (Old size - new size) */
 299                 unsigned int uncompressed_length = (count - 1) - session->d_stream.avail_out;
 300                 total_in_uncompressed += uncompressed_length;
 301
 302                 /* Null-terminate the buffer -- this doesnt harm binary data */
 303                 recvq.append(buffer, uncompressed_length);
 304                 return 1;
 305         }
 306
 307         int OnStreamSocketWrite(StreamSocket* user, std::string& sendq)
 308         {
 309                 int fd = user->GetFd();
 310                 izip_session* session = &sessions[fd];
 311
 312                 if(session->status != IZIP_OPEN)
 313                         /* Seriously, wtf? */
 314                         return -1;
 315
 316                 int ret;
 317
 318                 /* This loop is really only supposed to run once, but in case 'compr'
 319                  * is filled up somehow we are prepared to handle this situation.
 320                  */
 321                 unsigned int offset = 0;
 322                 do
 323                 {
 324                         /* Prepare compression */
 325                         session->c_stream.next_in = (Bytef*)sendq.data() + offset;
 326                         session->c_stream.avail_in = sendq.length() - offset;
 327
 328                         session->c_stream.next_out = (Bytef*)net_buffer;
 329                         session->c_stream.avail_out = net_buffer_size;
 330
 331                         /* Compress the text */
 332                         ret = deflate(&session->c_stream, Z_SYNC_FLUSH);
 333                         /* TODO CloseStream() in here at random places */
 334                         switch (ret)
 335                         {
 336                                 case Z_OK:
 337                                         break;
 338                                 case Z_BUF_ERROR:
 339                                         /* This one is non-fatal, buffer is just full
 340                                          * (can't happen here).
 341                                          */
 342                                         Error(session, "Internal error. This is not supposed to happen.");
 343                                         break;
 344                                 case Z_STREAM_ERROR:
 345                                         /* This is one of the 'not supposed to happen' things.
 346                                          * Memory corruption, anyone?
 347                                          */
 348                                         Error(session, "General Error. This is also not supposed to happen.");
 349                                         break;
 350                                 default:
 351                                         Error(session, "Unknown error");
 352                                         break;
 353                         }
 354
 355                         if (ret != Z_OK)
 356                                 return 0;
 357
 358                         /* Space before - space after stuff was added to this */
 359                         unsigned int compressed = net_buffer_size - session->c_stream.avail_out;
 360                         unsigned int uncompressed = sendq.length() - session->c_stream.avail_in;
 361
 362                         /* Make it skip the data which was compressed already */
 363                         offset += uncompressed;
 364
 365                         /* Update stats */
 366                         total_out_uncompressed += uncompressed;
 367                         total_out_compressed += compressed;
 368
 369                         /* Add compressed to the output buffer */
 370                         session->outbuf.append((const char*)net_buffer, compressed);
 371                 } while (session->c_stream.avail_in != 0);
 372
 373                 /* Lets see how much we can send out */
 374                 ret = write(fd, session->outbuf.data(), session->outbuf.length());
 375
 376                 /* Check for errors, and advance the buffer if any was sent */
 377                 if (ret > 0)
 378                         session->outbuf = session->outbuf.substr(ret);
 379                 else if (ret < 1)
 380                 {
 381                         if (errno == EAGAIN)
 382                                 return 0;
 383                         else
 384                         {
 385                                 session->outbuf.clear();
 386                                 return -1;
 387                         }
 388                 }
 389
 390                 return 1;
 391         }
 392
 393         void Error(izip_session* session, const std::string &text)
 394         {
 395                 ServerInstance->SNO->WriteToSnoMask('l', "ziplink error: " + text);
 396         }
 397
 398         void CloseSession(izip_session* session)
 399         {
 400                 if (session->status == IZIP_OPEN)
 401                 {
 402                         session->status = IZIP_CLOSED;
 403                         session->outbuf.clear();
 404                         inflateEnd(&session->d_stream);
 405                         deflateEnd(&session->c_stream);
 406                 }
 407         }
 408
 409 };
 410
 411 MODULE_INIT(ModuleZLib)
 412