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(InspIRCd* Me)
  60                 : Module(Me)
  61         {
  62                 ServerInstance->Modules->PublishInterface("BufferedSocketHook", this);
  63
  64                 sessions = new izip_session[ServerInstance->SE->GetMaxFds()];
  65                 for (int i = 0; i < ServerInstance->SE->GetMaxFds(); i++)
  66                         sessions[i].status = IZIP_CLOSED;
  67
  68                 total_out_compressed = total_in_compressed = 0;
  69                 total_out_uncompressed = total_in_uncompressed = 0;
  70                 Implementation eventlist[] = { I_OnStats, I_OnRequest };
  71                 ServerInstance->Modules->Attach(eventlist, this, 2);
  72
  73                 // Allocate a buffer which is used for reading and writing data
  74                 net_buffer_size = ServerInstance->Config->NetBufferSize;
  75                 net_buffer = new char[net_buffer_size];
  76         }
  77
  78         ~ModuleZLib()
  79         {
  80                 ServerInstance->Modules->UnpublishInterface("BufferedSocketHook", this);
  81                 delete[] sessions;
  82                 delete[] net_buffer;
  83         }
  84
  85         Version GetVersion()
  86         {
  87                 return Version("$Id$", VF_VENDOR, API_VERSION);
  88         }
  89
  90
  91         /* Handle BufferedSocketHook API requests */
  92         const char* OnRequest(Request* request)
  93         {
  94                 ISHRequest* ISR = (ISHRequest*)request;
  95                 if (strcmp("IS_NAME", request->GetId()) == 0)
  96                 {
  97                         /* Return name */
  98                         return "zip";
  99                 }
 100                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 101                 {
 102                         ISR->Sock->AddIOHook(this);
 103                         return "OK";
 104                 }
 105                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 106                 {
 107                         ISR->Sock->DelIOHook();
 108                         return "OK";
 109                 }
 110                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 111                 {
 112                         /* Check for completion of handshake
 113                          * (actually, this module doesnt handshake)
 114                          */
 115                         return "OK";
 116                 }
 117                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 118                 {
 119                         /* Attach certificate data to the inspsocket
 120                          * (this module doesnt do that, either)
 121                          */
 122                         return NULL;
 123                 }
 124                 return NULL;
 125         }
 126
 127         /* Handle stats z (misc stats) */
 128         ModResult OnStats(char symbol, User* user, string_list &results)
 129         {
 130                 if (symbol == 'z')
 131                 {
 132                         std::string sn = ServerInstance->Config->ServerName;
 133
 134                         /* Yeah yeah, i know, floats are ew.
 135                          * We used them here because we'd be casting to float anyway to do this maths,
 136                          * and also only floating point numbers can deal with the pretty large numbers
 137                          * involved in the total throughput of a server over a large period of time.
 138                          * (we dont count 64 bit ints because not all systems have 64 bit ints, and floats
 139                          * can still hold more.
 140                          */
 141                         float outbound_r = (total_out_compressed / (total_out_uncompressed + 0.001)) * 100;
 142                         float inbound_r = (total_in_compressed / (total_in_uncompressed + 0.001)) * 100;
 143
 144                         float total_compressed = total_in_compressed + total_out_compressed;
 145                         float total_uncompressed = total_in_uncompressed + total_out_uncompressed;
 146
 147                         float total_r = (total_compressed / (total_uncompressed + 0.001)) * 100;
 148
 149                         char outbound_ratio[MAXBUF], inbound_ratio[MAXBUF], combined_ratio[MAXBUF];
 150
 151                         sprintf(outbound_ratio, "%3.2f%%", outbound_r);
 152                         sprintf(inbound_ratio, "%3.2f%%", inbound_r);
 153                         sprintf(combined_ratio, "%3.2f%%", total_r);
 154
 155                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_compressed   = "+ConvToStr(total_out_compressed));
 156                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_compressed    = "+ConvToStr(total_in_compressed));
 157                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_uncompressed = "+ConvToStr(total_out_uncompressed));
 158                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_uncompressed  = "+ConvToStr(total_in_uncompressed));
 159                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS percentage_of_original_outbound_traffic        = "+outbound_ratio);
 160                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS percentage_of_orignal_inbound_traffic         = "+inbound_ratio);
 161                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS total_size_of_original_traffic        = "+combined_ratio);
 162                         return MOD_RES_PASSTHRU;
 163                 }
 164
 165                 return MOD_RES_PASSTHRU;
 166         }
 167
 168         void OnStreamSocketConnect(StreamSocket* user)
 169         {
 170                 OnStreamSocketAccept(user, 0, 0);
 171         }
 172
 173         void OnRawSocketAccept(StreamSocket* user, irc::sockets::sockaddrs*, irc::sockets::sockaddrs*)
 174         {
 175                 int fd = user->GetFd();
 176
 177                 izip_session* session = &sessions[fd];
 178
 179                 /* Just in case... */
 180                 session->outbuf.clear();
 181
 182                 session->c_stream.zalloc = (alloc_func)0;
 183                 session->c_stream.zfree = (free_func)0;
 184                 session->c_stream.opaque = (voidpf)0;
 185
 186                 session->d_stream.zalloc = (alloc_func)0;
 187                 session->d_stream.zfree = (free_func)0;
 188                 session->d_stream.opaque = (voidpf)0;
 189
 190                 /* If we cant call this, well, we're boned. */
 191                 if (inflateInit(&session->d_stream) != Z_OK)
 192                 {
 193                         session->status = IZIP_CLOSED;
 194                         return;
 195                 }
 196
 197                 /* Same here */
 198                 if (deflateInit(&session->c_stream, Z_BEST_COMPRESSION) != Z_OK)
 199                 {
 200                         inflateEnd(&session->d_stream);
 201                         session->status = IZIP_CLOSED;
 202                         return;
 203                 }
 204
 205                 /* Just in case, do this last */
 206                 session->status = IZIP_OPEN;
 207         }
 208
 209         void OnStreamSocketClose(StreamSocket* user)
 210         {
 211                 int fd = user->GetFd();
 212                 CloseSession(&sessions[fd]);
 213         }
 214
 215         int OnStreamSocketRead(StreamSocket* user, std::string& recvq)
 216         {
 217                 int fd = user->GetFd();
 218                 /* Find the sockets session */
 219                 izip_session* session = &sessions[fd];
 220
 221                 if (session->status == IZIP_CLOSED)
 222                         return -1;
 223
 224                 if (session->inbuf.empty())
 225                 {
 226                         /* Read read_buffer_size bytes at a time to the buffer (usually 2.5k) */
 227                         int readresult = read(fd, net_buffer, net_buffer_size);
 228
 229                         if (readresult < 0)
 230                         {
 231                                 if (errno == EINTR || errno == EAGAIN)
 232                                         return 0;
 233                         }
 234                         if (readresult <= 0)
 235                                 return -1;
 236
 237                         total_in_compressed += readresult;
 238
 239                         /* Copy the compressed data into our input buffer */
 240                         session->inbuf.append(net_buffer, readresult);
 241                 }
 242
 243                 size_t in_len = session->inbuf.length();
 244                 char* buffer = ServerInstance->GetReadBuffer();
 245                 int count = ServerInstance->Config->NetBufferSize;
 246
 247                 /* Prepare decompression */
 248                 session->d_stream.next_in = (Bytef *)session->inbuf.c_str();
 249                 session->d_stream.avail_in = in_len;
 250
 251                 session->d_stream.next_out = (Bytef*)buffer;
 252                 /* Last byte is reserved for NULL terminating that beast */
 253                 session->d_stream.avail_out = count - 1;
 254
 255                 /* Z_SYNC_FLUSH: Do as much as possible */
 256                 int ret = inflate(&session->d_stream, Z_SYNC_FLUSH);
 257                 /* TODO CloseStream() in here at random places */
 258                 switch (ret)
 259                 {
 260                         case Z_NEED_DICT:
 261                         case Z_STREAM_ERROR:
 262                                 /* This is one of the 'not supposed to happen' things.
 263                                  * Memory corruption, anyone?
 264                                  */
 265                                 Error(session, "General Error. This is not supposed to happen :/");
 266                                 break;
 267                         case Z_DATA_ERROR:
 268                                 Error(session, "Decompression failed, malformed data");
 269                                 break;
 270                         case Z_MEM_ERROR:
 271                                 Error(session, "Out of memory");
 272                                 break;
 273                         case Z_BUF_ERROR:
 274                                 /* This one is non-fatal, buffer is just full
 275                                  * (can't happen here).
 276                                  */
 277                                 Error(session, "Internal error. This is not supposed to happen.");
 278                                 break;
 279                         case Z_STREAM_END:
 280                                 /* This module *never* generates these :/ */
 281                                 Error(session, "End-of-stream marker received");
 282                                 break;
 283                         case Z_OK:
 284                                 break;
 285                         default:
 286                                 /* NO WAI! This can't happen. All errors are handled above. */
 287                                 Error(session, "Unknown error");
 288                                 break;
 289                 }
 290                 if (ret != Z_OK)
 291                 {
 292                         return -1;
 293                 }
 294
 295                 /* Update the inbut buffer */
 296                 unsigned int input_compressed = in_len - session->d_stream.avail_in;
 297                 session->inbuf = session->inbuf.substr(input_compressed);
 298
 299                 /* Update counters (Old size - new size) */
 300                 unsigned int uncompressed_length = (count - 1) - session->d_stream.avail_out;
 301                 total_in_uncompressed += uncompressed_length;
 302
 303                 /* Null-terminate the buffer -- this doesnt harm binary data */
 304                 recvq.append(buffer, uncompressed_length);
 305                 return 1;
 306         }
 307
 308         int OnStreamSocketWrite(StreamSocket* user, std::string& sendq)
 309         {
 310                 int fd = user->GetFd();
 311                 izip_session* session = &sessions[fd];
 312
 313                 if(session->status != IZIP_OPEN)
 314                         /* Seriously, wtf? */
 315                         return -1;
 316
 317                 int ret;
 318
 319                 /* This loop is really only supposed to run once, but in case 'compr'
 320                  * is filled up somehow we are prepared to handle this situation.
 321                  */
 322                 unsigned int offset = 0;
 323                 do
 324                 {
 325                         /* Prepare compression */
 326                         session->c_stream.next_in = (Bytef*)sendq.data() + offset;
 327                         session->c_stream.avail_in = sendq.length() - offset;
 328
 329                         session->c_stream.next_out = (Bytef*)net_buffer;
 330                         session->c_stream.avail_out = net_buffer_size;
 331
 332                         /* Compress the text */
 333                         ret = deflate(&session->c_stream, Z_SYNC_FLUSH);
 334                         /* TODO CloseStream() in here at random places */
 335                         switch (ret)
 336                         {
 337                                 case Z_OK:
 338                                         break;
 339                                 case Z_BUF_ERROR:
 340                                         /* This one is non-fatal, buffer is just full
 341                                          * (can't happen here).
 342                                          */
 343                                         Error(session, "Internal error. This is not supposed to happen.");
 344                                         break;
 345                                 case Z_STREAM_ERROR:
 346                                         /* This is one of the 'not supposed to happen' things.
 347                                          * Memory corruption, anyone?
 348                                          */
 349                                         Error(session, "General Error. This is also not supposed to happen.");
 350                                         break;
 351                                 default:
 352                                         Error(session, "Unknown error");
 353                                         break;
 354                         }
 355
 356                         if (ret != Z_OK)
 357                                 return 0;
 358
 359                         /* Space before - space after stuff was added to this */
 360                         unsigned int compressed = net_buffer_size - session->c_stream.avail_out;
 361                         unsigned int uncompressed = sendq.length() - session->c_stream.avail_in;
 362
 363                         /* Make it skip the data which was compressed already */
 364                         offset += uncompressed;
 365
 366                         /* Update stats */
 367                         total_out_uncompressed += uncompressed;
 368                         total_out_compressed += compressed;
 369
 370                         /* Add compressed to the output buffer */
 371                         session->outbuf.append((const char*)net_buffer, compressed);
 372                 } while (session->c_stream.avail_in != 0);
 373
 374                 /* Lets see how much we can send out */
 375                 ret = write(fd, session->outbuf.data(), session->outbuf.length());
 376
 377                 /* Check for errors, and advance the buffer if any was sent */
 378                 if (ret > 0)
 379                         session->outbuf = session->outbuf.substr(ret);
 380                 else if (ret < 1)
 381                 {
 382                         if (errno == EAGAIN)
 383                                 return 0;
 384                         else
 385                         {
 386                                 session->outbuf.clear();
 387                                 return -1;
 388                         }
 389                 }
 390
 391                 return 1;
 392         }
 393
 394         void Error(izip_session* session, const std::string &text)
 395         {
 396                 ServerInstance->SNO->WriteToSnoMask('l', "ziplink error: " + text);
 397         }
 398
 399         void CloseSession(izip_session* session)
 400         {
 401                 if (session->status == IZIP_OPEN)
 402                 {
 403                         session->status = IZIP_CLOSED;
 404                         session->outbuf.clear();
 405                         inflateEnd(&session->d_stream);
 406                         deflateEnd(&session->c_stream);
 407                 }
 408         }
 409
 410 };
 411
 412 MODULE_INIT(ModuleZLib)
 413