retchmail/wvpopclient.cc

   1 /*
   2  * Worldvisions Weaver Software:
   3  *   Copyright (C) 1997-2003 Net Integration Technologies, Inc.
   4  *
   5  * Avery's insanely fast alternative to Fetchmail -- Pop3 Client
   6  *
   7  * This code is LGPL - see the file COPYING.LIB for a full copy of the
   8  * license.
   9  */
  10
  11 #include <unistd.h>
  12 #include "wvstring.h"
  13 #include "wvpopclient.h"
  14 #include "wvistreamlist.h"
  15 #include "wvdigest.h"
  16 #include "wvhex.h"
  17 #include "strutils.h"
  18
  19 #define MAX_PROCESSES 5
  20 #define MAX_REQUESTS 10
  21
  22
  23 WvPopClient::WvPopClient(WvStream *conn, WvStringParm acct,
  24                          WvStringParm _password,
  25                          WvStringParm _deliverto, WvStringParm _mda,
  26                          bool _flushing, bool _apop_enable,
  27                          bool _apop_enable_fallback, bool _explode,
  28                          bool _safemode, bool _ignorerp)
  29   : WvStreamClone(conn), sendprocs(10),
  30     username(acctparse(acct)), // I hate constructors!
  31     password(_password), deliverto(_deliverto), mda(_mda),
  32     log(WvString("PopRetriever %s", acct), WvLog::Debug3),
  33     not_found(false)
  34 {
  35     uses_continue_select = true;
  36     personal_stack_size = 65536;
  37     never_select = false;
  38     flushing = _flushing;
  39     apop_enable = _apop_enable;
  40     apop_enable_fallback = _apop_enable_fallback;
  41     next_req = next_ack = sendmails = 0;
  42     explode = _explode;
  43     safemode = _safemode;
  44     ignorerp = _ignorerp;
  45     max_requests = MAX_REQUESTS;
  46
  47     if (safemode)
  48         max_requests = 1;
  49     safe_deletes.zap();
  50
  51     log(WvLog::Info, "Retrieve mail from %s into %s.\n", acct, deliverto);
  52 }
  53
  54
  55 WvPopClient::~WvPopClient()
  56 {
  57     if (isok()) // someone is killing us before our time
  58         seterr("Closed connection at user request.");
  59
  60     terminate_continue_select();
  61
  62     // disable callbacks for all remaining sendmail procs
  63     WvSendmailProcDict::Iter i(sendprocs);
  64     for (i.rewind(); i.next(); )
  65         i->cb = WvSendmailCallback();
  66
  67     if (geterr())
  68         log(WvLog::Error, "Aborted.  Error was: %s\n", errstr());
  69     else
  70         log(WvLog::Info, "Done.\n");
  71
  72     safe_deletes.zap();
  73 }
  74
  75
  76 WvString WvPopClient::acctparse(WvStringParm acct)
  77 {
  78     WvString u(acct);
  79     char *cptr = strrchr(u.edit(), '@');
  80
  81     if (cptr)
  82         *cptr = 0;
  83     return u;
  84 }
  85
  86
  87 void WvPopClient::cmd(WvStringParm s)
  88 {
  89     // If we're already dead, we should try doing anything...
  90     if (!isok())
  91         return;
  92
  93     print("%s\r\n", s);
  94
  95     if (!strncasecmp(s, "pass ", 5))
  96         trace.append(new WvString("pass"), true);
  97     else if (!strncasecmp(s, "apop ", 5))
  98         trace.append(new WvString("apop"), true);
  99     else
 100     {
 101         if (!strncasecmp(s, "apop ", 5))
 102             trace.append(new WvString("apop"), true);
 103         else
 104             trace.append(new WvString(s), true);
 105     }
 106
 107     if (!strncasecmp(s, "retr ", 5)) // less important
 108         log(WvLog::Debug3, "Send: %s\n", s);
 109     else if (!strncasecmp(s, "pass ", 5))    // hide passwords
 110         log(WvLog::Debug2, "Send: pass <NOT SHOWN>\n");
 111     else
 112         log(WvLog::Debug2, "Send: %s\n", s);
 113 }
 114
 115
 116 bool WvPopClient::response()
 117 {
 118     flush(0);
 119
 120     if (!isok())
 121     {
 122         log(WvLog::Critical,"Bailing out since the connection died: %s\n",
 123             errstr());
 124         return false;
 125     }
 126
 127     assert(!trace.isempty());
 128     WvStringList::Iter i(trace);
 129     i.rewind(); i.next();
 130
 131     char *line = blocking_getline(60*1000);
 132     if (!line)
 133     {
 134         if (isok())
 135             seterr(ETIMEDOUT);
 136         return false;
 137     }
 138
 139     log(WvLog::Debug2, "Recv(%s): %s\n", *i, line);
 140     i.unlink();
 141
 142     if (!strncmp(line, "+OK", 3))
 143     {
 144         res1 = res2 = 0;
 145         sscanf(line, "+OK %ld %ld", &res1, &res2);
 146         return true;
 147     }
 148
 149     return false;
 150 }
 151
 152
 153 static bool messcompare(const WvPopClient::MsgInfo &a,
 154                         const WvPopClient::MsgInfo &b)
 155 {
 156     const long base = 10240;
 157     long alen = a.len / base, blen = b.len / base;
 158     return ((alen * base + a.num) - (blen * base + b.num)) < 0;
 159 }
 160
 161
 162 void WvPopClient::pre_select(SelectInfo &si)
 163 {
 164     bool oldrd = si.wants.readable;
 165
 166     if (never_select)
 167         si.wants.readable = false;
 168     WvStreamClone::pre_select(si);
 169     si.wants.readable = oldrd;
 170 }
 171
 172
 173 bool WvPopClient::post_select(SelectInfo &si)
 174 {
 175     bool val, oldrd = si.wants.readable;
 176
 177     if (never_select)
 178         si.wants.readable = false;
 179     val = WvStreamClone::post_select(si);
 180     si.wants.readable = oldrd;
 181     return val;
 182 }
 183
 184
 185 void WvPopClient::execute()
 186 {
 187     const char format[] = "%20.20s> %-40.40s\n";
 188     char *line, *greeting, *start, *end, *cptr;
 189     int count, nmsgs;
 190     WvString from, subj;
 191     bool printed, in_head, msgdone;
 192
 193     WvStreamClone::execute();
 194
 195     // read hello header
 196     // Adapted for APOP by markj@luminas.co.uk
 197     // trace.append(new WvString("HELLO"), true);
 198     greeting = blocking_getline(60*1000);
 199     if (!greeting || strncmp(greeting,"+OK", 3)) goto fail;
 200     // if (!response()) goto fail;
 201     log(WvLog::Debug1, "Recv(HELLO): %s", greeting);
 202
 203     // log in
 204     if (apop_enable && strrchr(greeting, '>'))
 205     {
 206         // APOP login attempt -- early code from fetchmail
 207         /* build MD5 digest from greeting timestamp + password */
 208         /* find start of timestamp */
 209         for (start = greeting;  *start != 0 && *start != '<';  start++)
 210             continue;
 211         if (*start == 0) goto fail;
 212
 213         /* find end of timestamp */
 214         for (end = start;  *end != 0  && *end != '>';  end++)
 215             continue;
 216         if (*end == 0 || end == start + 1) goto fail;
 217         else
 218             *++end = '\0';
 219         // end of fetchmail code
 220         //
 221         log(WvLog::Debug2, "Using APOP seed: %s\n", start);
 222
 223         /* copy timestamp and password into digestion buffer */
 224         WvString digestsecret("%s%s",start,password);
 225         WvDynBuf md5buf;
 226         WvMD5Digest().flushstrbuf(digestsecret, md5buf, true /*finish*/);
 227         WvString md5hex = WvHexEncoder().strflushbuf(md5buf, true);
 228
 229         log(WvLog::Debug2, "Using APOP response: %s\n", md5hex);
 230         cmd("apop %s %s", username, md5hex);
 231     }
 232
 233     if (!apop_enable || !strrchr(greeting, '>')
 234         || (!response() && apop_enable_fallback))
 235     {
 236         // USER/PASS login
 237         // some providers (i.e.: gmail) get unhappy if you send the user+pass
 238         // together, so wait for a response to the user cmd before sending
 239         // password.
 240         cmd("user %s", username);
 241         if (!response()) goto fail;
 242         cmd("pass %s", password);
 243         if (!response())
 244         {
 245            seterr("Server denied access.  Wrong password?");
 246            return;
 247         }
 248     }
 249
 250     // get the number of messages
 251     cmd("stat");
 252     cmd("list"); // for later
 253     if (!response()) goto fail;
 254     log(WvLog::Info, "%s %s in %s bytes.\n", res1,
 255         res1==1 ? "message" : "messages", res2);
 256     nmsgs = res1;
 257     mess.reserve(nmsgs);
 258
 259     // get the list of messages and their sizes
 260     if (!response()) goto fail;
 261     for (count = 0; count < nmsgs; count++)
 262     {
 263         line = blocking_getline(60*1000);
 264         mess.push_back(MsgInfo());
 265         if (!isok() || !line ||
 266             sscanf(line, "%d %ld",
 267                    &(mess[count].num), &(mess[count].len)) != 2)
 268         {
 269             log(WvLog::Error, "Invalid LIST response: '%s'\n", line);
 270             goto fail;
 271         }
 272     }
 273     line = blocking_getline(60*1000);
 274     if (!isok() || !line || strcmp(line, ".") && strcmp(line, ".\r"))
 275     {
 276         log(WvLog::Error, "Invalid LIST terminator: '%s'\n", line);
 277         goto fail;
 278     }
 279
 280     // sort the list in order of size
 281     std::sort(mess.begin(), mess.end(), messcompare);
 282
 283     while (next_ack < nmsgs
 284            || (next_ack && mess[next_ack-1].deletes_after_this)
 285            || sendmails || safe_deletes.count() > 0)
 286     {
 287         if (!isok()) break;
 288         log(WvLog::Debug4, "next_ack=%s/%s dels=%s sendmails=%s/%s\n",
 289             next_ack, nmsgs,
 290             mess[0].deletes_after_this, sendmails,
 291             WvSendmailProc::num_sendmails);
 292
 293         // do any necessary safe deletes
 294         while (safemode && safe_deletes.count() > 0 &&
 295                 next_req-next_ack < max_requests)
 296         {
 297             cmd(safe_deletes.popstr());
 298             if (!response())
 299             {
 300                 log(WvLog::Warning, "Failed safe deleting a message!?\n");
 301                 if (flushing)
 302                     log(WvLog::Warning, "Canceling future deletions "
 303                         "to protect the innocent.\n");
 304                 flushing = false;
 305                 safe_deletes.zap();
 306             }
 307
 308             if (!isok())
 309                 goto fail;
 310         }
 311
 312         while (next_req < nmsgs && next_req-next_ack < max_requests)
 313         {
 314             cmd("retr %s", mess[next_req].num);
 315             next_req++;
 316         }
 317
 318         MsgInfo *m = &mess[next_ack];
 319
 320         while (next_ack > 0 && mess[next_ack-1].deletes_after_this)
 321         {
 322             if (!response())
 323             {
 324                 log(WvLog::Warning, "Failed deleting a message!?\n");
 325                 if (flushing)
 326                     log(WvLog::Warning, "Canceling future deletions "
 327                         "to protect the innocent.\n");
 328                 flushing = false;
 329             }
 330
 331             mess[next_ack-1].deletes_after_this--;
 332
 333             if (!isok())
 334                 goto fail;
 335         }
 336
 337         if (next_ack >= nmsgs)
 338         {
 339             never_select = true;
 340             continue_select(20);
 341             never_select = false;
 342             continue; // only deletions and/or sendmails remaining
 343         }
 344
 345         if (!response() && isok())
 346         {
 347             next_ack++;
 348             log(WvLog::Warning, "Hmm... missing message #%s.\n", m->num);
 349             continue;
 350         }
 351
 352         if (!isok())
 353         {
 354             if (!geterr()) // Keep the older, better?, error message
 355                 seterr("Aborted.\n");
 356             return;
 357         }
 358
 359         next_ack++;
 360
 361         WvString size;
 362         if (m->len > 10*1024*1024)
 363             size = WvString("%sM", m->len/1024/1024);
 364         else if (m->len >= 10*1024)
 365             size = WvString("%sk", m->len/1024);
 366         else if (m->len > 1024)
 367             size = WvString("%s.%sk", m->len/1024, (m->len*10/1024) % 10);
 368         else
 369             size = WvString("%sb", m->len);
 370
 371         log(WvLog::Debug1, "%-6s %6s ",
 372             WvString("[%s]", mess[next_ack-1].num), size);
 373
 374         from = "";
 375         subj = "";
 376         printed = false;
 377         in_head = true;
 378         msgdone = false;
 379
 380         while (WvSendmailProc::num_sendmails >= MAX_PROCESSES && isok())
 381         {
 382             never_select = true;
 383             continue_select(1000);
 384             never_select = false;
 385         }
 386
 387         {
 388             if (access(mda, X_OK))
 389             {
 390                 log(WvLog::Error, "%s: %s\n", mda, strerror(errno));
 391                 not_found = true;
 392                 goto fail;
 393             }
 394         }
 395         const char *argv[] = {mda, deliverto, NULL};
 396         //const char *argv[] = {"dd", "of=/dev/null", NULL};
 397         WvSendmailProc *p = NULL;
 398         if (!explode)
 399           {
 400             p = new WvSendmailProc(argv, next_ack-1,
 401                                    wv::bind(&WvPopClient::send_done, this,
 402                                             _1, _2));
 403             sendmails++;
 404           }
 405
 406         while ((line = blocking_getline(60*1000)) != NULL)
 407         {
 408             if (!isok())
 409             {
 410                 if (p)
 411                   p->kill(SIGTERM);
 412                 seterr("Connection dropped while reading message contents!");
 413                 return;
 414             }
 415
 416             // remove \r character, if the server gave one
 417             cptr = strchr(line, 0) - 1;
 418             if (*cptr == '\r')
 419                 *cptr = 0;
 420
 421             if (line[0]==0 || line[0]=='\r')
 422                 in_head = false;
 423             if (line[0]=='.')
 424             {
 425                 if (!strcmp(line, ".") || !strcmp(line, ".\r"))
 426                 {
 427                     msgdone = true;
 428                     break; // dot on a line by itself: done this message.
 429                 }
 430                 else
 431                 {
 432                     // POP servers turn any line *starting with* a dot into
 433                     // a line starting with dot-dot; so remove the extra
 434                     // dot.
 435                     line++;
 436                 }
 437             }
 438
 439             if (in_head && !strncasecmp(line, "From: ", 6))
 440             {
 441                 cptr = strchr(line+6, '<');
 442                 if (cptr)
 443                 {
 444                     WvString tmp(cptr + 1);
 445                     cptr = strchr(tmp.edit(), '>');
 446                     if (cptr)
 447                         *cptr = 0;
 448                     from = WvString("<%s", tmp);
 449                 }
 450                 else
 451                     from = line+6;
 452                 trim_string(from.edit());
 453             }
 454             else if (in_head && explode && !p
 455                      && !strncasecmp(line, "X-Envelope-To: ", 14))
 456             {
 457                 WvString sendto = line+strlen("X-Envelope-To:");
 458                 sendto.edit();
 459                 cptr = strchr(sendto, '@');
 460                 if (cptr)
 461                     *cptr = 0;
 462                 trim_string(sendto.edit());
 463                 const char *argvE[] = {mda, sendto, NULL};
 464                 p = new WvSendmailProc(argvE, next_ack-1,
 465                                        wv::bind(&WvPopClient::send_done, this,
 466                                                 _1, _2));
 467                 sendmails++;
 468             }
 469             else if (in_head && !strncasecmp(line, "Subject: ", 9))
 470             {
 471                 subj = line+9;
 472                 trim_string(subj.edit());
 473             }
 474
 475             if (!!from && !!subj && !printed)
 476             {
 477                 log(WvLog::Debug1, format, from, subj);
 478                 printed = true;
 479             }
 480
 481             // ideally we might try to fix the Return-Path here but that
 482             // could turn out to be a parsing nightmare so we're going to
 483             // just dump it if their POP3 server mangles it
 484             //
 485             if (p && (!in_head || !ignorerp ||
 486                         strncasecmp(line, "Return-Path: ", 13)))
 487                 p->print("%s\n", line);
 488         }
 489
 490         if (isok() && !msgdone)
 491         {
 492             if (p)
 493                 p->kill(SIGTERM);
 494             seterr(ETIMEDOUT);
 495             return;
 496         }
 497
 498         if (isok() && !printed)
 499         {
 500             if (!subj) subj = "<NO SUBJECT>";
 501             if (!from) from = "<NO SENDER";
 502             log(WvLog::Debug1, format, from, subj);
 503         }
 504
 505         if (p)
 506         {
 507             p->done();
 508             WvIStreamList::globallist.append(p, true, "sendmail");
 509             sendprocs.add(p, false);
 510         }
 511     }
 512
 513     cmd("quit");
 514     if (!response()) goto fail;
 515
 516     close();
 517     return;
 518
 519 fail:
 520     if (cloned && cloned->geterr())
 521         seterr("Server connection error: %s", cloned->errstr());
 522     else if (!cloned || !cloned->isok())
 523         seterr("Server connection closed unexpectedly (%s bytes left)!",
 524                cloned ? inbuf.used() : 0);
 525     else if (not_found)
 526         seterr("MDA could not be executed!");
 527     else
 528         seterr("Server said something unexpected!");
 529     return;
 530 }
 531
 532
 533 void WvPopClient::send_done(int count, bool success)
 534 {
 535     log(WvLog::Debug4, "send_done %s (success=%s)\n", count+1, success);
 536
 537     WvSendmailProc *proc = sendprocs[count];
 538     if (proc)
 539         sendprocs.remove(proc);
 540
 541     sendmails--;
 542
 543     if (!success)
 544     {
 545         log(WvLog::Warning, "Error delivering message %s to the MDA.\n",
 546             mess[count].num);
 547     }
 548     else
 549     {
 550         mess[count].sent = true;
 551
 552         // remember that we had one more delete message after the most recent
 553         // request (which might have no relation to the message we're deleting,
 554         // but we have to count responses carefully!)
 555         if (flushing)
 556         {
 557             // in safe mode we do all deletes at the end
 558             if (safemode)
 559             {
 560                 log(WvLog::Debug3, "Queueing message %s for deletion\n",
 561                         mess[count].num);
 562                 safe_deletes.append(
 563                         new WvString("dele %s", mess[count].num), true);
 564             }
 565             else
 566             {
 567                 cmd("dele %s", mess[count].num);
 568                 mess[next_req-1].deletes_after_this++;
 569             }
 570         }
 571     }
 572
 573     // wake up the WvPopClient, which may have been waiting for a sendmail
 574     // to finish.
 575     never_select = false;
 576 }
 577
 578