pop3.c

   1 /*@ S-nail - a mail user agent derived from Berkeley Mail.
   2  *@ POP3 (RFCs 1939, 2595) client.
   3  *
   4  * Copyright (c) 2000-2004 Gunnar Ritter, Freiburg i. Br., Germany.
   5  * Copyright (c) 2012 - 2014 Steffen (Daode) Nurpmeso <sdaoden@users.sf.net>.
   6  */
   7 /*
   8  * Copyright (c) 2002
   9  * Gunnar Ritter.  All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. All advertising materials mentioning features or use of this software
  20  *    must display the following acknowledgement:
  21  *    This product includes software developed by Gunnar Ritter
  22  *    and his contributors.
  23  * 4. Neither the name of Gunnar Ritter nor the names of his contributors
  24  *    may be used to endorse or promote products derived from this software
  25  *    without specific prior written permission.
  26  *
  27  * THIS SOFTWARE IS PROVIDED BY GUNNAR RITTER AND CONTRIBUTORS ``AS IS'' AND
  28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  30  * ARE DISCLAIMED.  IN NO EVENT SHALL GUNNAR RITTER OR CONTRIBUTORS BE LIABLE
  31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  37  * SUCH DAMAGE.
  38  */
  39
  40 #ifndef HAVE_AMALGAMATION
  41 # include "nail.h"
  42 #endif
  43
  44 EMPTY_FILE(pop3)
  45 #ifdef HAVE_POP3
  46
  47 #undef NL
  48 #undef LINE
  49 #define NL        "\015\012"
  50 #define LINE(X)   X NL
  51
  52 #define POP3_ANSWER(RV,ACTIONSTOP) \
  53 do if (((RV) = pop3_answer(mp)) == STOP) {\
  54    ACTIONSTOP;\
  55 } while (0)
  56
  57 #define POP3_OUT(RV,X,Y,ACTIONSTOP) \
  58 do {\
  59    if (((RV) = pop3_finish(mp)) == STOP) {\
  60       ACTIONSTOP;\
  61    }\
  62    if (options & OPT_VERBVERB)\
  63       fprintf(stderr, ">>> %s", X);\
  64    mp->mb_active |= Y;\
  65    if (((RV) = swrite(&mp->mb_sock, X)) == STOP) {\
  66       ACTIONSTOP;\
  67    }\
  68 } while (0)
  69
  70 static char             *_pop3_buf;
  71 static size_t           _pop3_bufsize;
  72 static sigjmp_buf       _pop3_jmp;
  73 static sighandler_type  _pop3_savealrm;
  74 static int              _pop3_keepalive;
  75 static int volatile     _pop3_lock;
  76
  77 /* Perform entire login handshake */
  78 static enum okay  _pop3_login(struct mailbox *mp, struct sockconn *scp);
  79
  80 /* APOP: get greeting credential or NULL */
  81 #ifdef HAVE_MD5
  82 static char *     _pop3_lookup_apop_timestamp(char const *bp);
  83 #endif
  84
  85 static bool_t     _pop3_use_starttls(struct sockconn const *scp);
  86
  87 /* APOP: shall we use it? */
  88 static bool_t     _pop3_no_apop(struct sockconn const *scp);
  89
  90 /* Several authentication methods */
  91 #ifdef HAVE_MD5
  92 static enum okay  _pop3_auth_apop(struct mailbox *mp,
  93                      struct sockconn const *scp, char const *ts);
  94 #endif
  95 static enum okay  _pop3_auth_plain(struct mailbox *mp,
  96                      struct sockconn const *scp);
  97
  98 static void       pop3_timer_off(void);
  99 static enum okay  pop3_answer(struct mailbox *mp);
 100 static enum okay  pop3_finish(struct mailbox *mp);
 101 static void       pop3catch(int s);
 102 static void       _pop3_maincatch(int s);
 103 static enum okay  pop3_noop1(struct mailbox *mp);
 104 static void       pop3alarm(int s);
 105 static enum okay  pop3_stat(struct mailbox *mp, off_t *size, int *cnt);
 106 static enum okay  pop3_list(struct mailbox *mp, int n, size_t *size);
 107 static void       pop3_init(struct mailbox *mp, int n);
 108 static void       pop3_dates(struct mailbox *mp);
 109 static void       pop3_setptr(struct mailbox *mp);
 110 static enum okay  pop3_get(struct mailbox *mp, struct message *m,
 111                      enum needspec need);
 112 static enum okay  pop3_exit(struct mailbox *mp);
 113 static enum okay  pop3_delete(struct mailbox *mp, int n);
 114 static enum okay  pop3_update(struct mailbox *mp);
 115
 116 static enum okay
 117 _pop3_login(struct mailbox *mp, struct sockconn *scp)
 118 {
 119 #ifdef HAVE_MD5
 120    char *ts;
 121 #endif
 122    enum okay rv;
 123    NYD_ENTER;
 124
 125    /* Get the greeting, check wether APOP is advertised */
 126    POP3_ANSWER(rv, goto jleave);
 127 #ifdef HAVE_MD5
 128    ts = _pop3_lookup_apop_timestamp(_pop3_buf);
 129 #endif
 130
 131    /* If not yet secured, can we upgrade to TLS? */
 132 #ifdef HAVE_SSL
 133    if (!scp->sc_url.url_needs_tls && _pop3_use_starttls(scp)) {
 134       POP3_OUT(rv, "STLS" NL, MB_COMD, goto jleave);
 135       POP3_ANSWER(rv, goto jleave);
 136       if ((rv = ssl_open(scp->sc_url.url_host.s, &scp->sc_sock,
 137             scp->sc_url.url_u_h_p.s)) != OKAY)
 138          goto jleave;
 139    }
 140 #else
 141    if (_pop3_use_starttls(scp->sc_url.url_u_h_p.s)) {
 142       fprintf(stderr, "No SSL support compiled in.\n");
 143       rv = STOP;
 144       goto jleave;
 145    }
 146 #endif
 147
 148    /* Use the APOP single roundtrip? */
 149    if (!_pop3_no_apop(scp)) {
 150 #ifdef HAVE_MD5
 151       if (ts != NULL) {
 152          if ((rv = _pop3_auth_apop(mp, scp, ts)) != OKAY)
 153             fprintf(stderr, _("POP3 `APOP' authentication failed, "
 154                "maybe try setting *pop3-no-apop*\n"));
 155          goto jleave;
 156       } else
 157 #endif
 158       if (options & OPT_VERB)
 159          fprintf(stderr, _("No POP3 `APOP' support "
 160             "available, sending password in clear text\n"));
 161    }
 162
 163    rv = _pop3_auth_plain(mp, scp);
 164 jleave:
 165    NYD_LEAVE;
 166    return rv;
 167 }
 168
 169 #ifdef HAVE_MD5
 170 static char *
 171 _pop3_lookup_apop_timestamp(char const *bp)
 172 {
 173    /* RFC 1939:
 174     * A POP3 server which implements the APOP command will include
 175     * a timestamp in its banner greeting.  The syntax of the timestamp
 176     * corresponds to the `msg-id' in [RFC822]
 177     * RFC 822:
 178     * msg-id   = "<" addr-spec ">"
 179     * addr-spec   = local-part "@" domain */
 180    char const *cp, *ep;
 181    size_t tl;
 182    char *rp = NULL;
 183    bool_t hadat = FAL0;
 184    NYD_ENTER;
 185
 186    if ((cp = strchr(bp, '<')) == NULL)
 187       goto jleave;
 188
 189    /* xxx What about malformed APOP timestamp (<@>) here? */
 190    for (ep = cp; *ep != '\0'; ++ep) {
 191       if (spacechar(*ep))
 192          goto jleave;
 193       else if (*ep == '@')
 194          hadat = TRU1;
 195       else if (*ep == '>') {
 196          if (!hadat)
 197             goto jleave;
 198          break;
 199       }
 200    }
 201    if (*ep != '>')
 202       goto jleave;
 203
 204    tl = PTR2SIZE(++ep - cp);
 205    rp = salloc(tl +1);
 206    memcpy(rp, cp, tl);
 207    rp[tl] = '\0';
 208 jleave:
 209    NYD_LEAVE;
 210    return rp;
 211 }
 212 #endif
 213
 214 static bool_t
 215 _pop3_use_starttls(struct sockconn const *scp)
 216 {
 217    bool_t rv;
 218    NYD_ENTER;
 219
 220    if (!(rv = ok_blook(pop3_use_starttls)))
 221       if (!ok_blook(v15_compat) ||
 222             !(rv = vok_blook(savecat("pop3-use-starttls-",
 223                   scp->sc_url.url_h_p.s))))
 224          rv = vok_blook(savecat("pop3-use-starttls-", scp->sc_url.url_u_h_p.s));
 225    NYD_LEAVE;
 226    return rv;
 227 }
 228
 229 static bool_t
 230 _pop3_no_apop(struct sockconn const *scp)
 231 {
 232    bool_t rv;
 233    NYD_ENTER;
 234
 235    if (!(rv = ok_blook(pop3_no_apop)))
 236       if (!ok_blook(v15_compat) ||
 237             !(rv = vok_blook(savecat("pop3-no-apop-", scp->sc_url.url_h_p.s))))
 238          rv = vok_blook(savecat("pop3-no-apop-", scp->sc_url.url_u_h_p.s));
 239    NYD_LEAVE;
 240    return rv;
 241 }
 242
 243 #ifdef HAVE_MD5
 244 static enum okay
 245 _pop3_auth_apop(struct mailbox *mp, struct sockconn const *scp, char const *ts)
 246 {
 247    unsigned char digest[16];
 248    char hex[MD5TOHEX_SIZE], *cp;
 249    md5_ctx ctx;
 250    size_t i;
 251    enum okay rv = STOP;
 252    NYD_ENTER;
 253
 254    md5_init(&ctx);
 255    md5_update(&ctx, (uc_i*)UNCONST(ts), strlen(ts));
 256    md5_update(&ctx, (uc_i*)scp->sc_cred.cc_pass.s, scp->sc_cred.cc_pass.l);
 257    md5_final(digest, &ctx);
 258    md5tohex(hex, digest);
 259
 260    i = scp->sc_cred.cc_user.l;
 261    cp = ac_alloc(5 + i + 1 + MD5TOHEX_SIZE + sizeof(NL)-1 +1);
 262
 263    memcpy(cp, "APOP ", 5);
 264    memcpy(cp + 5, scp->sc_cred.cc_user.s, i);
 265    i += 5;
 266    cp[i++] = ' ';
 267    memcpy(cp + i, hex, MD5TOHEX_SIZE);
 268    i += MD5TOHEX_SIZE;
 269    memcpy(cp + i, NL, sizeof(NL));
 270    POP3_OUT(rv, cp, MB_COMD, goto jleave);
 271    POP3_ANSWER(rv, goto jleave);
 272
 273    rv = OKAY;
 274 jleave:
 275    ac_free(cp);
 276    NYD_LEAVE;
 277    return rv;
 278 }
 279 #endif /* HAVE_MD5 */
 280
 281 static enum okay
 282 _pop3_auth_plain(struct mailbox *mp, struct sockconn const *scp)
 283 {
 284    char *cp;
 285    enum okay rv = STOP;
 286    NYD_ENTER;
 287
 288    /* The USER/PASS plain text version */
 289    cp = ac_alloc(MAX(scp->sc_cred.cc_user.l, scp->sc_cred.cc_pass.l) + 5 +
 290          sizeof(NL)-1 +1);
 291
 292    memcpy(cp, "USER ", 5);
 293    memcpy(cp + 5, scp->sc_cred.cc_user.s, scp->sc_cred.cc_user.l);
 294    memcpy(cp + 5 + scp->sc_cred.cc_user.l, NL, sizeof(NL));
 295    POP3_OUT(rv, cp, MB_COMD, goto jleave);
 296    POP3_ANSWER(rv, goto jleave);
 297
 298    memcpy(cp, "PASS ", 5);
 299    memcpy(cp + 5, scp->sc_cred.cc_pass.s, scp->sc_cred.cc_pass.l);
 300    memcpy(cp + 5 + scp->sc_cred.cc_pass.l, NL, sizeof(NL));
 301    POP3_OUT(rv, cp, MB_COMD, goto jleave);
 302    POP3_ANSWER(rv, goto jleave);
 303
 304    rv = OKAY;
 305 jleave:
 306    ac_free(cp);
 307    NYD_LEAVE;
 308    return rv;
 309 }
 310
 311 static void
 312 pop3_timer_off(void)
 313 {
 314    NYD_ENTER;
 315    if (_pop3_keepalive > 0) {
 316       alarm(0);
 317       safe_signal(SIGALRM, _pop3_savealrm);
 318    }
 319    NYD_LEAVE;
 320 }
 321
 322 static enum okay
 323 pop3_answer(struct mailbox *mp)
 324 {
 325    int sz;
 326    enum okay rv = STOP;
 327    NYD_ENTER;
 328
 329 jretry:
 330    if ((sz = sgetline(&_pop3_buf, &_pop3_bufsize, NULL, &mp->mb_sock)) > 0) {
 331       if ((mp->mb_active & (MB_COMD | MB_MULT)) == MB_MULT)
 332          goto jmultiline;
 333       if (options & OPT_VERBVERB)
 334          fputs(_pop3_buf, stderr);
 335       switch (*_pop3_buf) {
 336       case '+':
 337          rv = OKAY;
 338          mp->mb_active &= ~MB_COMD;
 339          break;
 340       case '-':
 341          rv = STOP;
 342          mp->mb_active = MB_NONE;
 343          fprintf(stderr, _("POP3 error: %s"), _pop3_buf);
 344          break;
 345       default:
 346          /* If the answer starts neither with '+' nor with '-', it must be part
 347           * of a multiline response.  Get lines until a single dot appears */
 348 jmultiline:
 349          while (_pop3_buf[0] != '.' || _pop3_buf[1] != NL[0] ||
 350                _pop3_buf[2] != NL[1] || _pop3_buf[3] != '\0') {
 351             sz = sgetline(&_pop3_buf, &_pop3_bufsize, NULL, &mp->mb_sock);
 352             if (sz <= 0)
 353                goto jeof;
 354          }
 355          mp->mb_active &= ~MB_MULT;
 356          if (mp->mb_active != MB_NONE)
 357             goto jretry;
 358       }
 359    } else {
 360 jeof:
 361       rv = STOP;
 362       mp->mb_active = MB_NONE;
 363    }
 364    NYD_LEAVE;
 365    return rv;
 366 }
 367
 368 static enum okay
 369 pop3_finish(struct mailbox *mp)
 370 {
 371    NYD_ENTER;
 372    while (mp->mb_sock.s_fd > 0 && mp->mb_active != MB_NONE)
 373       pop3_answer(mp);
 374    NYD_LEAVE;
 375    return OKAY;
 376 }
 377
 378 static void
 379 pop3catch(int s)
 380 {
 381    NYD_X; /* Signal handler */
 382    switch (s) {
 383    case SIGINT:
 384       fprintf(stderr, _("Interrupt\n"));
 385       siglongjmp(_pop3_jmp, 1);
 386       break;
 387    case SIGPIPE:
 388       fprintf(stderr, "Received SIGPIPE during POP3 operation\n");
 389       break;
 390    }
 391 }
 392
 393 static void
 394 _pop3_maincatch(int s)
 395 {
 396    NYD_X; /* Signal handler */
 397    UNUSED(s);
 398
 399    if (interrupts++ == 0)
 400       fprintf(stderr, _("Interrupt\n"));
 401    else
 402       onintr(0);
 403 }
 404
 405 static enum okay
 406 pop3_noop1(struct mailbox *mp)
 407 {
 408    enum okay rv;
 409    NYD_ENTER;
 410
 411    POP3_OUT(rv, "NOOP" NL, MB_COMD, goto jleave);
 412    POP3_ANSWER(rv, goto jleave);
 413 jleave:
 414    NYD_LEAVE;
 415    return rv;
 416 }
 417
 418 static void
 419 pop3alarm(int s)
 420 {
 421    sighandler_type volatile saveint, savepipe;
 422    NYD_X; /* Signal handler */
 423    UNUSED(s);
 424
 425    if (_pop3_lock++ == 0) {
 426       if ((saveint = safe_signal(SIGINT, SIG_IGN)) != SIG_IGN)
 427          safe_signal(SIGINT, &_pop3_maincatch);
 428       savepipe = safe_signal(SIGPIPE, SIG_IGN);
 429       if (sigsetjmp(_pop3_jmp, 1)) {
 430          safe_signal(SIGINT, saveint);
 431          safe_signal(SIGPIPE, savepipe);
 432          goto jbrk;
 433       }
 434       if (savepipe != SIG_IGN)
 435          safe_signal(SIGPIPE, pop3catch);
 436       if (pop3_noop1(&mb) != OKAY) {
 437          safe_signal(SIGINT, saveint);
 438          safe_signal(SIGPIPE, savepipe);
 439          goto jleave;
 440       }
 441       safe_signal(SIGINT, saveint);
 442       safe_signal(SIGPIPE, savepipe);
 443    }
 444 jbrk:
 445    alarm(_pop3_keepalive);
 446 jleave:
 447    --_pop3_lock;
 448 }
 449
 450 static enum okay
 451 pop3_stat(struct mailbox *mp, off_t *size, int *cnt)
 452 {
 453    char *cp;
 454    enum okay rv;
 455    NYD_ENTER;
 456
 457    POP3_OUT(rv, "STAT" NL, MB_COMD, goto jleave);
 458    POP3_ANSWER(rv, goto jleave);
 459
 460    for (cp = _pop3_buf; *cp != '\0' && !spacechar(*cp); ++cp)
 461       ;
 462    while (*cp != '\0' && spacechar(*cp))
 463       ++cp;
 464
 465    if (*cp != '\0') {
 466       *cnt = (int)strtol(cp, NULL, 10);
 467       while (*cp != '\0' && !spacechar(*cp))
 468          ++cp;
 469       while (*cp != '\0' && spacechar(*cp))
 470          ++cp;
 471       if (*cp != '\0')
 472          *size = (int)strtol(cp, NULL, 10);
 473       else
 474          rv = STOP;
 475    } else
 476       rv = STOP;
 477
 478    if (rv == STOP)
 479       fprintf(stderr, _("invalid POP3 STAT response: %s\n"), _pop3_buf);
 480 jleave:
 481    NYD_LEAVE;
 482    return rv;
 483 }
 484
 485 static enum okay
 486 pop3_list(struct mailbox *mp, int n, size_t *size)
 487 {
 488    char o[LINESIZE], *cp;
 489    enum okay rv;
 490    NYD_ENTER;
 491
 492    snprintf(o, sizeof o, "LIST %u" NL, n);
 493    POP3_OUT(rv, o, MB_COMD, goto jleave);
 494    POP3_ANSWER(rv, goto jleave);
 495
 496    for (cp = _pop3_buf; *cp != '\0' && !spacechar(*cp); ++cp)
 497       ;
 498    while (*cp != '\0' && spacechar(*cp))
 499       ++cp;
 500    while (*cp != '\0' && !spacechar(*cp))
 501       ++cp;
 502    while (*cp != '\0' && spacechar(*cp))
 503       ++cp;
 504    if (*cp != '\0')
 505       *size = (size_t)strtol(cp, NULL, 10);
 506    else
 507       *size = 0;
 508 jleave:
 509    NYD_LEAVE;
 510    return rv;
 511 }
 512
 513 static void
 514 pop3_init(struct mailbox *mp, int n)
 515 {
 516    struct message *m;
 517    char *cp;
 518    NYD_ENTER;
 519
 520    m =  message + n;
 521    m->m_flag = MUSED | MNEW | MNOFROM | MNEWEST;
 522    m->m_block = 0;
 523    m->m_offset = 0;
 524    pop3_list(mp, PTR2SIZE(m - message + 1), &m->m_xsize);
 525
 526    if ((cp = hfield1("status", m)) != NULL) {
 527       while (*cp != '\0') {
 528          if (*cp == 'R')
 529             m->m_flag |= MREAD;
 530          else if (*cp == 'O')
 531             m->m_flag &= ~MNEW;
 532          ++cp;
 533       }
 534    }
 535    NYD_LEAVE;
 536 }
 537
 538 static void
 539 pop3_dates(struct mailbox *mp)
 540 {
 541    size_t i;
 542    NYD_ENTER;
 543    UNUSED(mp);
 544
 545    for (i = 0; UICMP(z, i, <, msgCount); ++i)
 546       substdate(message + i);
 547    NYD_LEAVE;
 548 }
 549
 550 static void
 551 pop3_setptr(struct mailbox *mp)
 552 {
 553    size_t i;
 554    NYD_ENTER;
 555
 556    message = scalloc(msgCount + 1, sizeof *message);
 557    for (i = 0; UICMP(z, i, <, msgCount); ++i)
 558       pop3_init(mp, i);
 559
 560    setdot(message);
 561    message[msgCount].m_size = 0;
 562    message[msgCount].m_lines = 0;
 563    pop3_dates(mp);
 564    NYD_LEAVE;
 565 }
 566
 567 static enum okay
 568 pop3_get(struct mailbox *mp, struct message *m, enum needspec volatile need)
 569 {
 570    char o[LINESIZE], *line, *lp;
 571    sighandler_type volatile saveint, savepipe;
 572    size_t linesize, linelen, size;
 573    int number, lines;
 574    int volatile emptyline;
 575    off_t offset;
 576    enum okay volatile rv;
 577    NYD_ENTER;
 578
 579    line = NULL; /* TODO line pool */
 580    saveint = savepipe = SIG_IGN;
 581    linesize = 0;
 582    number = (int)PTR2SIZE(m - message + 1);
 583    emptyline = 0;
 584    rv = STOP;
 585
 586    if (mp->mb_sock.s_fd < 0) {
 587       fprintf(stderr, _("POP3 connection already closed.\n"));
 588       ++_pop3_lock;
 589       goto jleave;
 590    }
 591
 592    if (_pop3_lock++ == 0) {
 593       if ((saveint = safe_signal(SIGINT, SIG_IGN)) != SIG_IGN)
 594          safe_signal(SIGINT, &_pop3_maincatch);
 595       savepipe = safe_signal(SIGPIPE, SIG_IGN);
 596       if (sigsetjmp(_pop3_jmp, 1)) {
 597          safe_signal(SIGINT, saveint);
 598          safe_signal(SIGPIPE, savepipe);
 599          --_pop3_lock;
 600          goto jleave;
 601       }
 602       if (savepipe != SIG_IGN)
 603          safe_signal(SIGPIPE, pop3catch);
 604    }
 605
 606    fseek(mp->mb_otf, 0L, SEEK_END);
 607    offset = ftell(mp->mb_otf);
 608 jretry:
 609    switch (need) {
 610    case NEED_HEADER:
 611       snprintf(o, sizeof o, "TOP %u 0" NL, number);
 612       break;
 613    case NEED_BODY:
 614       snprintf(o, sizeof o, "RETR %u" NL, number);
 615       break;
 616    case NEED_UNSPEC:
 617       abort(); /* XXX */
 618    }
 619    POP3_OUT(rv, o, MB_COMD | MB_MULT, goto jleave);
 620
 621    if (pop3_answer(mp) == STOP) {
 622       if (need == NEED_HEADER) {
 623          /* The TOP POP3 command is optional, so retry with entire message */
 624          need = NEED_BODY;
 625          goto jretry;
 626       }
 627       goto jleave;
 628    }
 629
 630    size = 0;
 631    lines = 0;
 632    while (sgetline(&line, &linesize, &linelen, &mp->mb_sock) > 0) {
 633       if (line[0] == '.' && line[1] == NL[0] && line[2] == NL[1] &&
 634             line[3] == '\0') {
 635          mp->mb_active &= ~MB_MULT;
 636          break;
 637       }
 638       if (line[0] == '.') {
 639          lp = line + 1;
 640          --linelen;
 641       } else
 642          lp = line;
 643       /* TODO >>
 644        * Need to mask 'From ' lines. This cannot be done properly
 645        * since some servers pass them as 'From ' and others as
 646        * '>From '. Although one could identify the first kind of
 647        * server in principle, it is not possible to identify the
 648        * second as '>From ' may also come from a server of the
 649        * first type as actual data. So do what is absolutely
 650        * necessary only - mask 'From '.
 651        *
 652        * If the line is the first line of the message header, it
 653        * is likely a real 'From ' line. In this case, it is just
 654        * ignored since it violates all standards.
 655        * TODO i have *never* seen the latter?!?!?
 656        * TODO <<
 657        */
 658       /* Since we simply copy over data without doing any transfer
 659        * encoding reclassification/adjustment we *have* to perform
 660        * RFC 4155 compliant From_ quoting here */
 661       if (is_head(lp, linelen)) {
 662          DBG( fprintf(stderr, "!! POP3 really needs to quote From?\n"); )
 663          if (lines == 0)
 664             continue;
 665          fputc('>', mp->mb_otf);
 666          ++size;
 667       }
 668       lines++;
 669       if (lp[linelen-1] == NL[1] && (linelen == 1 || lp[linelen-2] == NL[0])) {
 670          emptyline = linelen <= 2;
 671          if (linelen > 2)
 672             fwrite(lp, 1, linelen - 2, mp->mb_otf);
 673          fputc('\n', mp->mb_otf);
 674          size += linelen - 1;
 675       } else {
 676          emptyline = 0;
 677          fwrite(lp, 1, linelen, mp->mb_otf);
 678          size += linelen;
 679       }
 680    }
 681    if (!emptyline) {
 682       /* This is very ugly; but some POP3 daemons don't end a
 683        * message with NL NL, and we need \n\n for mbox format */
 684       fputc('\n', mp->mb_otf);
 685       ++lines;
 686       ++size;
 687    }
 688    m->m_size = size;
 689    m->m_lines = lines;
 690    m->m_block = mailx_blockof(offset);
 691    m->m_offset = mailx_offsetof(offset);
 692    fflush(mp->mb_otf);
 693
 694    switch (need) {
 695    case NEED_HEADER:
 696       m->m_have |= HAVE_HEADER;
 697       break;
 698    case NEED_BODY:
 699       m->m_have |= HAVE_HEADER | HAVE_BODY;
 700       m->m_xlines = m->m_lines;
 701       m->m_xsize = m->m_size;
 702       break;
 703    case NEED_UNSPEC:
 704       break;
 705    }
 706
 707    rv = OKAY;
 708 jleave:
 709    if (line != NULL)
 710       free(line);
 711    if (saveint != SIG_IGN)
 712       safe_signal(SIGINT, saveint);
 713    if (savepipe != SIG_IGN)
 714       safe_signal(SIGPIPE, savepipe);
 715    --_pop3_lock;
 716    NYD_LEAVE;
 717    if (interrupts)
 718       onintr(0);
 719    return rv;
 720 }
 721
 722 static enum okay
 723 pop3_exit(struct mailbox *mp)
 724 {
 725    enum okay rv;
 726    NYD_ENTER;
 727
 728    POP3_OUT(rv, "QUIT" NL, MB_COMD, goto jleave);
 729    POP3_ANSWER(rv, goto jleave);
 730 jleave:
 731    NYD_LEAVE;
 732    return rv;
 733 }
 734
 735 static enum okay
 736 pop3_delete(struct mailbox *mp, int n)
 737 {
 738    char o[LINESIZE];
 739    enum okay rv;
 740    NYD_ENTER;
 741
 742    snprintf(o, sizeof o, "DELE %u" NL, n);
 743    POP3_OUT(rv, o, MB_COMD, goto jleave);
 744    POP3_ANSWER(rv, goto jleave);
 745 jleave:
 746    NYD_LEAVE;
 747    return rv;
 748 }
 749
 750 static enum okay
 751 pop3_update(struct mailbox *mp)
 752 {
 753    struct message *m;
 754    int dodel, c, gotcha, held;
 755    NYD_ENTER;
 756
 757    if (!edit) {
 758       holdbits();
 759       c = 0;
 760       for (m = message; PTRCMP(m, <, message + msgCount); ++m)
 761          if (m->m_flag & MBOX)
 762             ++c;
 763       if (c > 0)
 764          makembox();
 765    }
 766
 767    gotcha = held = 0;
 768    for (m = message; PTRCMP(m, <, message + msgCount); ++m) {
 769       if (edit)
 770          dodel = m->m_flag & MDELETED;
 771       else
 772          dodel = !((m->m_flag & MPRESERVE) || !(m->m_flag & MTOUCH));
 773       if (dodel) {
 774          pop3_delete(mp, PTR2SIZE(m - message + 1));
 775          ++gotcha;
 776       } else
 777          ++held;
 778    }
 779    if (gotcha && edit) {
 780       printf(_("\"%s\" "), displayname);
 781       printf((ok_blook(bsdcompat) || ok_blook(bsdmsgs))
 782          ? _("complete\n") : _("updated.\n"));
 783    } else if (held && !edit) {
 784       if (held == 1)
 785          printf(_("Held 1 message in %s\n"), displayname);
 786       else
 787          printf(_("Held %d messages in %s\n"), held, displayname);
 788    }
 789    fflush(stdout);
 790    NYD_LEAVE;
 791    return OKAY;
 792 }
 793
 794 FL enum okay
 795 pop3_noop(void)
 796 {
 797    sighandler_type volatile saveint, savepipe;
 798    enum okay rv = STOP;
 799    NYD_ENTER;
 800
 801    _pop3_lock = 1;
 802    if ((saveint = safe_signal(SIGINT, SIG_IGN)) != SIG_IGN)
 803       safe_signal(SIGINT, &_pop3_maincatch);
 804    savepipe = safe_signal(SIGPIPE, SIG_IGN);
 805    if (sigsetjmp(_pop3_jmp, 1) == 0) {
 806       if (savepipe != SIG_IGN)
 807          safe_signal(SIGPIPE, pop3catch);
 808       rv = pop3_noop1(&mb);
 809    }
 810    safe_signal(SIGINT, saveint);
 811    safe_signal(SIGPIPE, savepipe);
 812    _pop3_lock = 0;
 813    NYD_LEAVE;
 814    return rv;
 815 }
 816
 817 FL int
 818 pop3_setfile(char const *server, enum fedit_mode fm)
 819 {
 820    struct sockconn sc;
 821    sighandler_type saveint, savepipe;
 822    char const *cp;
 823    int volatile rv;
 824    NYD_ENTER;
 825
 826    rv = 1;
 827    if (fm & FEDIT_NEWMAIL)
 828       goto jleave;
 829    rv = -1;
 830
 831    if (!url_parse(&sc.sc_url, CPROTO_POP3, server))
 832       goto jleave;
 833    if (!ok_blook(v15_compat) &&
 834          (!sc.sc_url.url_had_user || sc.sc_url.url_pass.s != NULL)) {
 835       fprintf(stderr, "New-style URL used without *v15-compat* being set\n");
 836       goto jleave;
 837    }
 838
 839    if (!(ok_blook(v15_compat) ? ccred_lookup(&sc.sc_cred, &sc.sc_url)
 840          : ccred_lookup_old(&sc.sc_cred, CPROTO_POP3,
 841             (sc.sc_url.url_had_user ? sc.sc_url.url_eu_h_p.s
 842              : sc.sc_url.url_u_h_p.s))))
 843       goto jleave;
 844
 845    if (!sopen(&sc.sc_sock, &sc.sc_url))
 846       goto jleave;
 847
 848    rv = 1;
 849    quit();
 850
 851    edit = !(fm & FEDIT_SYSBOX);
 852    if (mb.mb_sock.s_fd >= 0)
 853       sclose(&mb.mb_sock);
 854    if (mb.mb_itf) {
 855       fclose(mb.mb_itf);
 856       mb.mb_itf = NULL;
 857    }
 858    if (mb.mb_otf) {
 859       fclose(mb.mb_otf);
 860       mb.mb_otf = NULL;
 861    }
 862
 863    initbox(sc.sc_url.url_p_u_h_p);
 864    mb.mb_type = MB_VOID;
 865    _pop3_lock = 1;
 866    mb.mb_sock = sc.sc_sock;
 867
 868    saveint = safe_signal(SIGINT, SIG_IGN);
 869    savepipe = safe_signal(SIGPIPE, SIG_IGN);
 870    if (sigsetjmp(_pop3_jmp, 1)) {
 871       sclose(&mb.mb_sock);
 872       safe_signal(SIGINT, saveint);
 873       safe_signal(SIGPIPE, savepipe);
 874       _pop3_lock = 0;
 875       goto jleave;
 876    }
 877    if (saveint != SIG_IGN)
 878       safe_signal(SIGINT, pop3catch);
 879    if (savepipe != SIG_IGN)
 880       safe_signal(SIGPIPE, pop3catch);
 881
 882    if ((cp = ok_vlook(pop3_keepalive)) != NULL) {
 883       if ((_pop3_keepalive = (int)strtol(cp, NULL, 10)) > 0) {
 884          _pop3_savealrm = safe_signal(SIGALRM, pop3alarm);
 885          alarm(_pop3_keepalive);
 886       }
 887    }
 888
 889    mb.mb_sock.s_desc = sc.sc_url.url_proto;
 890    mb.mb_sock.s_onclose = pop3_timer_off;
 891    if (_pop3_login(&mb, &sc) != OKAY ||
 892          pop3_stat(&mb, &mailsize, &msgCount) != OKAY) {
 893       sclose(&mb.mb_sock);
 894       pop3_timer_off();
 895       safe_signal(SIGINT, saveint);
 896       safe_signal(SIGPIPE, savepipe);
 897       _pop3_lock = 0;
 898       goto jleave;
 899    }
 900    mb.mb_type = MB_POP3;
 901    mb.mb_perm = ((options & OPT_R_FLAG) || (fm & FEDIT_RDONLY)) ? 0 : MB_DELE;
 902    pop3_setptr(&mb);
 903    setmsize(msgCount);
 904    sawcom = FAL0;
 905
 906    safe_signal(SIGINT, saveint);
 907    safe_signal(SIGPIPE, savepipe);
 908    _pop3_lock = 0;
 909    if (!edit && msgCount == 0) {
 910       if (mb.mb_type == MB_POP3 && !ok_blook(emptystart))
 911          fprintf(stderr, _("No mail at %s\n"), server);
 912       goto jleave;
 913    }
 914
 915    rv = 0;
 916 jleave:
 917    NYD_LEAVE;
 918    return rv;
 919 }
 920
 921 FL enum okay
 922 pop3_header(struct message *m)
 923 {
 924    enum okay rv;
 925    NYD_ENTER;
 926
 927    rv = pop3_get(&mb, m, (ok_blook(pop3_bulk_load) ? NEED_BODY : NEED_HEADER));
 928    NYD_LEAVE;
 929    return rv;
 930 }
 931
 932 FL enum okay
 933 pop3_body(struct message *m)
 934 {
 935    enum okay rv;
 936    NYD_ENTER;
 937
 938    rv = pop3_get(&mb, m, NEED_BODY);
 939    NYD_LEAVE;
 940    return rv;
 941 }
 942
 943 FL void
 944 pop3_quit(void)
 945 {
 946    sighandler_type volatile saveint, savepipe;
 947    NYD_ENTER;
 948
 949    if (mb.mb_sock.s_fd < 0) {
 950       fprintf(stderr, _("POP3 connection already closed.\n"));
 951       goto jleave;
 952    }
 953
 954    _pop3_lock = 1;
 955    saveint = safe_signal(SIGINT, SIG_IGN);
 956    savepipe = safe_signal(SIGPIPE, SIG_IGN);
 957    if (sigsetjmp(_pop3_jmp, 1)) {
 958       safe_signal(SIGINT, saveint);
 959       safe_signal(SIGPIPE, saveint);
 960       _pop3_lock = 0;
 961       goto jleave;
 962    }
 963    if (saveint != SIG_IGN)
 964       safe_signal(SIGINT, pop3catch);
 965    if (savepipe != SIG_IGN)
 966       safe_signal(SIGPIPE, pop3catch);
 967    pop3_update(&mb);
 968    pop3_exit(&mb);
 969    sclose(&mb.mb_sock);
 970    safe_signal(SIGINT, saveint);
 971    safe_signal(SIGPIPE, savepipe);
 972    _pop3_lock = 0;
 973 jleave:
 974    NYD_LEAVE;
 975 }
 976
 977 #undef LINE
 978 #undef NL
 979 #endif /* HAVE_POP3 */
 980
 981 /* s-it-mode */