imap-send.c

   1 /*
   2  * git-imap-send - drops patches into an imap Drafts folder
   3  *                 derived from isync/mbsync - mailbox synchronizer
   4  *
   5  * Copyright (C) 2000-2002 Michael R. Elkins <me@mutt.org>
   6  * Copyright (C) 2002-2004 Oswald Buddenhagen <ossi@users.sf.net>
   7  * Copyright (C) 2004 Theodore Y. Ts'o <tytso@mit.edu>
   8  * Copyright (C) 2006 Mike McCormack
   9  *
  10  *  This program is free software; you can redistribute it and/or modify
  11  *  it under the terms of the GNU General Public License as published by
  12  *  the Free Software Foundation; either version 2 of the License, or
  13  *  (at your option) any later version.
  14  *
  15  *  This program is distributed in the hope that it will be useful,
  16  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  *  GNU General Public License for more details.
  19  *
  20  *  You should have received a copy of the GNU General Public License
  21  *  along with this program; if not, see <https://www.gnu.org/licenses/>.
  22  */
  23
  24 #include "git-compat-util.h"
  25 #include "config.h"
  26 #include "credential.h"
  27 #include "gettext.h"
  28 #include "run-command.h"
  29 #include "parse-options.h"
  30 #include "setup.h"
  31 #include "strbuf.h"
  32 #if defined(NO_OPENSSL) && !defined(HAVE_OPENSSL_CSPRNG)
  33 typedef void *SSL;
  34 #endif
  35 #ifdef USE_CURL_FOR_IMAP_SEND
  36 #include "http.h"
  37 #endif
  38
  39 #if defined(USE_CURL_FOR_IMAP_SEND)
  40 /* Always default to curl if it's available. */
  41 #define USE_CURL_DEFAULT 1
  42 #else
  43 /* We don't have curl, so continue to use the historical implementation */
  44 #define USE_CURL_DEFAULT 0
  45 #endif
  46
  47 static int verbosity;
  48 static int use_curl = USE_CURL_DEFAULT;
  49
  50 static const char * const imap_send_usage[] = { "git imap-send [-v] [-q] [--[no-]curl] < <mbox>", NULL };
  51
  52 static struct option imap_send_options[] = {
  53         OPT__VERBOSITY(&verbosity),
  54         OPT_BOOL(0, "curl", &use_curl, "use libcurl to communicate with the IMAP server"),
  55         OPT_END()
  56 };
  57
  58 #undef DRV_OK
  59 #define DRV_OK          0
  60 #define DRV_MSG_BAD     -1
  61 #define DRV_BOX_BAD     -2
  62 #define DRV_STORE_BAD   -3
  63
  64 __attribute__((format (printf, 1, 2)))
  65 static void imap_info(const char *, ...);
  66 __attribute__((format (printf, 1, 2)))
  67 static void imap_warn(const char *, ...);
  68
  69 static char *next_arg(char **);
  70
  71 __attribute__((format (printf, 3, 4)))
  72 static int nfsnprintf(char *buf, int blen, const char *fmt, ...);
  73
  74 static int nfvasprintf(char **strp, const char *fmt, va_list ap)
  75 {
  76         int len;
  77         char tmp[8192];
  78
  79         len = vsnprintf(tmp, sizeof(tmp), fmt, ap);
  80         if (len < 0)
  81                 die("Fatal: Out of memory");
  82         if (len >= sizeof(tmp))
  83                 die("imap command overflow!");
  84         *strp = xmemdupz(tmp, len);
  85         return len;
  86 }
  87
  88 struct imap_server_conf {
  89         const char *name;
  90         const char *tunnel;
  91         const char *host;
  92         int port;
  93         const char *folder;
  94         const char *user;
  95         const char *pass;
  96         int use_ssl;
  97         int ssl_verify;
  98         int use_html;
  99         const char *auth_method;
 100 };
 101
 102 static struct imap_server_conf server = {
 103         .ssl_verify = 1,
 104 };
 105
 106 struct imap_socket {
 107         int fd[2];
 108         SSL *ssl;
 109 };
 110
 111 struct imap_buffer {
 112         struct imap_socket sock;
 113         int bytes;
 114         int offset;
 115         char buf[1024];
 116 };
 117
 118 struct imap_cmd;
 119
 120 struct imap {
 121         int uidnext; /* from SELECT responses */
 122         unsigned caps, rcaps; /* CAPABILITY results */
 123         /* command queue */
 124         int nexttag, num_in_progress, literal_pending;
 125         struct imap_cmd *in_progress, **in_progress_append;
 126         struct imap_buffer buf; /* this is BIG, so put it last */
 127 };
 128
 129 struct imap_store {
 130         /* currently open mailbox */
 131         const char *name; /* foreign! maybe preset? */
 132         int uidvalidity;
 133         struct imap *imap;
 134         const char *prefix;
 135 };
 136
 137 struct imap_cmd_cb {
 138         int (*cont)(struct imap_store *ctx, const char *prompt);
 139         void *ctx;
 140         char *data;
 141         int dlen;
 142 };
 143
 144 struct imap_cmd {
 145         struct imap_cmd *next;
 146         struct imap_cmd_cb cb;
 147         char *cmd;
 148         int tag;
 149 };
 150
 151 #define CAP(cap) (imap->caps & (1 << (cap)))
 152
 153 enum CAPABILITY {
 154         NOLOGIN = 0,
 155         UIDPLUS,
 156         LITERALPLUS,
 157         NAMESPACE,
 158         STARTTLS,
 159         AUTH_CRAM_MD5
 160 };
 161
 162 static const char *cap_list[] = {
 163         "LOGINDISABLED",
 164         "UIDPLUS",
 165         "LITERAL+",
 166         "NAMESPACE",
 167         "STARTTLS",
 168         "AUTH=CRAM-MD5",
 169 };
 170
 171 #define RESP_OK    0
 172 #define RESP_NO    1
 173 #define RESP_BAD   2
 174
 175 static int get_cmd_result(struct imap_store *ctx, struct imap_cmd *tcmd);
 176
 177
 178 #ifndef NO_OPENSSL
 179 static void ssl_socket_perror(const char *func)
 180 {
 181         fprintf(stderr, "%s: %s\n", func, ERR_error_string(ERR_get_error(), NULL));
 182 }
 183 #endif
 184
 185 static void socket_perror(const char *func, struct imap_socket *sock, int ret)
 186 {
 187 #ifndef NO_OPENSSL
 188         if (sock->ssl) {
 189                 int sslerr = SSL_get_error(sock->ssl, ret);
 190                 switch (sslerr) {
 191                 case SSL_ERROR_NONE:
 192                         break;
 193                 case SSL_ERROR_SYSCALL:
 194                         perror("SSL_connect");
 195                         break;
 196                 default:
 197                         ssl_socket_perror("SSL_connect");
 198                         break;
 199                 }
 200         } else
 201 #endif
 202         {
 203                 if (ret < 0)
 204                         perror(func);
 205                 else
 206                         fprintf(stderr, "%s: unexpected EOF\n", func);
 207         }
 208         /* mark as used to appease -Wunused-parameter with NO_OPENSSL */
 209         (void)sock;
 210 }
 211
 212 #ifdef NO_OPENSSL
 213 static int ssl_socket_connect(struct imap_socket *sock UNUSED,
 214                               int use_tls_only UNUSED,
 215                               int verify UNUSED)
 216 {
 217         fprintf(stderr, "SSL requested but SSL support not compiled in\n");
 218         return -1;
 219 }
 220
 221 #else
 222
 223 static int host_matches(const char *host, const char *pattern)
 224 {
 225         if (pattern[0] == '*' && pattern[1] == '.') {
 226                 pattern += 2;
 227                 if (!(host = strchr(host, '.')))
 228                         return 0;
 229                 host++;
 230         }
 231
 232         return *host && *pattern && !strcasecmp(host, pattern);
 233 }
 234
 235 static int verify_hostname(X509 *cert, const char *hostname)
 236 {
 237         int len;
 238         X509_NAME *subj;
 239         char cname[1000];
 240         int i, found;
 241         STACK_OF(GENERAL_NAME) *subj_alt_names;
 242
 243         /* try the DNS subjectAltNames */
 244         found = 0;
 245         if ((subj_alt_names = X509_get_ext_d2i(cert, NID_subject_alt_name, NULL, NULL))) {
 246                 int num_subj_alt_names = sk_GENERAL_NAME_num(subj_alt_names);
 247                 for (i = 0; !found && i < num_subj_alt_names; i++) {
 248                         GENERAL_NAME *subj_alt_name = sk_GENERAL_NAME_value(subj_alt_names, i);
 249                         if (subj_alt_name->type == GEN_DNS &&
 250                             strlen((const char *)subj_alt_name->d.ia5->data) == (size_t)subj_alt_name->d.ia5->length &&
 251                             host_matches(hostname, (const char *)(subj_alt_name->d.ia5->data)))
 252                                 found = 1;
 253                 }
 254                 sk_GENERAL_NAME_pop_free(subj_alt_names, GENERAL_NAME_free);
 255         }
 256         if (found)
 257                 return 0;
 258
 259         /* try the common name */
 260         if (!(subj = X509_get_subject_name(cert)))
 261                 return error("cannot get certificate subject");
 262         if ((len = X509_NAME_get_text_by_NID(subj, NID_commonName, cname, sizeof(cname))) < 0)
 263                 return error("cannot get certificate common name");
 264         if (strlen(cname) == (size_t)len && host_matches(hostname, cname))
 265                 return 0;
 266         return error("certificate owner '%s' does not match hostname '%s'",
 267                      cname, hostname);
 268 }
 269
 270 static int ssl_socket_connect(struct imap_socket *sock, int use_tls_only, int verify)
 271 {
 272 #if (OPENSSL_VERSION_NUMBER >= 0x10000000L)
 273         const SSL_METHOD *meth;
 274 #else
 275         SSL_METHOD *meth;
 276 #endif
 277         SSL_CTX *ctx;
 278         int ret;
 279         X509 *cert;
 280
 281         SSL_library_init();
 282         SSL_load_error_strings();
 283
 284         meth = SSLv23_method();
 285         if (!meth) {
 286                 ssl_socket_perror("SSLv23_method");
 287                 return -1;
 288         }
 289
 290         ctx = SSL_CTX_new(meth);
 291         if (!ctx) {
 292                 ssl_socket_perror("SSL_CTX_new");
 293                 return -1;
 294         }
 295
 296         if (use_tls_only)
 297                 SSL_CTX_set_options(ctx, SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3);
 298
 299         if (verify)
 300                 SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER, NULL);
 301
 302         if (!SSL_CTX_set_default_verify_paths(ctx)) {
 303                 ssl_socket_perror("SSL_CTX_set_default_verify_paths");
 304                 return -1;
 305         }
 306         sock->ssl = SSL_new(ctx);
 307         if (!sock->ssl) {
 308                 ssl_socket_perror("SSL_new");
 309                 return -1;
 310         }
 311         if (!SSL_set_rfd(sock->ssl, sock->fd[0])) {
 312                 ssl_socket_perror("SSL_set_rfd");
 313                 return -1;
 314         }
 315         if (!SSL_set_wfd(sock->ssl, sock->fd[1])) {
 316                 ssl_socket_perror("SSL_set_wfd");
 317                 return -1;
 318         }
 319
 320 #ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME
 321         /*
 322          * SNI (RFC4366)
 323          * OpenSSL does not document this function, but the implementation
 324          * returns 1 on success, 0 on failure after calling SSLerr().
 325          */
 326         ret = SSL_set_tlsext_host_name(sock->ssl, server.host);
 327         if (ret != 1)
 328                 warning("SSL_set_tlsext_host_name(%s) failed.", server.host);
 329 #endif
 330
 331         ret = SSL_connect(sock->ssl);
 332         if (ret <= 0) {
 333                 socket_perror("SSL_connect", sock, ret);
 334                 return -1;
 335         }
 336
 337         if (verify) {
 338                 /* make sure the hostname matches that of the certificate */
 339                 cert = SSL_get_peer_certificate(sock->ssl);
 340                 if (!cert)
 341                         return error("unable to get peer certificate.");
 342                 if (verify_hostname(cert, server.host) < 0)
 343                         return -1;
 344         }
 345
 346         return 0;
 347 }
 348 #endif
 349
 350 static int socket_read(struct imap_socket *sock, char *buf, int len)
 351 {
 352         ssize_t n;
 353 #ifndef NO_OPENSSL
 354         if (sock->ssl)
 355                 n = SSL_read(sock->ssl, buf, len);
 356         else
 357 #endif
 358                 n = xread(sock->fd[0], buf, len);
 359         if (n <= 0) {
 360                 socket_perror("read", sock, n);
 361                 close(sock->fd[0]);
 362                 close(sock->fd[1]);
 363                 sock->fd[0] = sock->fd[1] = -1;
 364         }
 365         return n;
 366 }
 367
 368 static int socket_write(struct imap_socket *sock, const char *buf, int len)
 369 {
 370         int n;
 371 #ifndef NO_OPENSSL
 372         if (sock->ssl)
 373                 n = SSL_write(sock->ssl, buf, len);
 374         else
 375 #endif
 376                 n = write_in_full(sock->fd[1], buf, len);
 377         if (n != len) {
 378                 socket_perror("write", sock, n);
 379                 close(sock->fd[0]);
 380                 close(sock->fd[1]);
 381                 sock->fd[0] = sock->fd[1] = -1;
 382         }
 383         return n;
 384 }
 385
 386 static void socket_shutdown(struct imap_socket *sock)
 387 {
 388 #ifndef NO_OPENSSL
 389         if (sock->ssl) {
 390                 SSL_shutdown(sock->ssl);
 391                 SSL_free(sock->ssl);
 392         }
 393 #endif
 394         close(sock->fd[0]);
 395         close(sock->fd[1]);
 396 }
 397
 398 /* simple line buffering */
 399 static int buffer_gets(struct imap_buffer *b, char **s)
 400 {
 401         int n;
 402         int start = b->offset;
 403
 404         *s = b->buf + start;
 405
 406         for (;;) {
 407                 /* make sure we have enough data to read the \r\n sequence */
 408                 if (b->offset + 1 >= b->bytes) {
 409                         if (start) {
 410                                 /* shift down used bytes */
 411                                 *s = b->buf;
 412
 413                                 assert(start <= b->bytes);
 414                                 n = b->bytes - start;
 415
 416                                 if (n)
 417                                         memmove(b->buf, b->buf + start, n);
 418                                 b->offset -= start;
 419                                 b->bytes = n;
 420                                 start = 0;
 421                         }
 422
 423                         n = socket_read(&b->sock, b->buf + b->bytes,
 424                                          sizeof(b->buf) - b->bytes);
 425
 426                         if (n <= 0)
 427                                 return -1;
 428
 429                         b->bytes += n;
 430                 }
 431
 432                 if (b->buf[b->offset] == '\r') {
 433                         assert(b->offset + 1 < b->bytes);
 434                         if (b->buf[b->offset + 1] == '\n') {
 435                                 b->buf[b->offset] = 0;  /* terminate the string */
 436                                 b->offset += 2; /* next line */
 437                                 if (0 < verbosity)
 438                                         puts(*s);
 439                                 return 0;
 440                         }
 441                 }
 442
 443                 b->offset++;
 444         }
 445         /* not reached */
 446 }
 447
 448 __attribute__((format (printf, 1, 2)))
 449 static void imap_info(const char *msg, ...)
 450 {
 451         va_list va;
 452
 453         if (0 <= verbosity) {
 454                 va_start(va, msg);
 455                 vprintf(msg, va);
 456                 va_end(va);
 457                 fflush(stdout);
 458         }
 459 }
 460
 461 __attribute__((format (printf, 1, 2)))
 462 static void imap_warn(const char *msg, ...)
 463 {
 464         va_list va;
 465
 466         if (-2 < verbosity) {
 467                 va_start(va, msg);
 468                 vfprintf(stderr, msg, va);
 469                 va_end(va);
 470         }
 471 }
 472
 473 static char *next_arg(char **s)
 474 {
 475         char *ret;
 476
 477         if (!s || !*s)
 478                 return NULL;
 479         while (isspace((unsigned char) **s))
 480                 (*s)++;
 481         if (!**s) {
 482                 *s = NULL;
 483                 return NULL;
 484         }
 485         if (**s == '"') {
 486                 ++*s;
 487                 ret = *s;
 488                 *s = strchr(*s, '"');
 489         } else {
 490                 ret = *s;
 491                 while (**s && !isspace((unsigned char) **s))
 492                         (*s)++;
 493         }
 494         if (*s) {
 495                 if (**s)
 496                         *(*s)++ = 0;
 497                 if (!**s)
 498                         *s = NULL;
 499         }
 500         return ret;
 501 }
 502
 503 __attribute__((format (printf, 3, 4)))
 504 static int nfsnprintf(char *buf, int blen, const char *fmt, ...)
 505 {
 506         int ret;
 507         va_list va;
 508
 509         va_start(va, fmt);
 510         if (blen <= 0 || (unsigned)(ret = vsnprintf(buf, blen, fmt, va)) >= (unsigned)blen)
 511                 BUG("buffer too small. Please report a bug.");
 512         va_end(va);
 513         return ret;
 514 }
 515
 516 static struct imap_cmd *issue_imap_cmd(struct imap_store *ctx,
 517                                        struct imap_cmd_cb *cb,
 518                                        const char *fmt, va_list ap)
 519 {
 520         struct imap *imap = ctx->imap;
 521         struct imap_cmd *cmd;
 522         int n, bufl;
 523         char buf[1024];
 524
 525         cmd = xmalloc(sizeof(struct imap_cmd));
 526         nfvasprintf(&cmd->cmd, fmt, ap);
 527         cmd->tag = ++imap->nexttag;
 528
 529         if (cb)
 530                 cmd->cb = *cb;
 531         else
 532                 memset(&cmd->cb, 0, sizeof(cmd->cb));
 533
 534         while (imap->literal_pending)
 535                 get_cmd_result(ctx, NULL);
 536
 537         if (!cmd->cb.data)
 538                 bufl = nfsnprintf(buf, sizeof(buf), "%d %s\r\n", cmd->tag, cmd->cmd);
 539         else
 540                 bufl = nfsnprintf(buf, sizeof(buf), "%d %s{%d%s}\r\n",
 541                                   cmd->tag, cmd->cmd, cmd->cb.dlen,
 542                                   CAP(LITERALPLUS) ? "+" : "");
 543
 544         if (0 < verbosity) {
 545                 if (imap->num_in_progress)
 546                         printf("(%d in progress) ", imap->num_in_progress);
 547                 if (!starts_with(cmd->cmd, "LOGIN"))
 548                         printf(">>> %s", buf);
 549                 else
 550                         printf(">>> %d LOGIN <user> <pass>\n", cmd->tag);
 551         }
 552         if (socket_write(&imap->buf.sock, buf, bufl) != bufl) {
 553                 free(cmd->cmd);
 554                 free(cmd);
 555                 if (cb)
 556                         free(cb->data);
 557                 return NULL;
 558         }
 559         if (cmd->cb.data) {
 560                 if (CAP(LITERALPLUS)) {
 561                         n = socket_write(&imap->buf.sock, cmd->cb.data, cmd->cb.dlen);
 562                         free(cmd->cb.data);
 563                         if (n != cmd->cb.dlen ||
 564                             socket_write(&imap->buf.sock, "\r\n", 2) != 2) {
 565                                 free(cmd->cmd);
 566                                 free(cmd);
 567                                 return NULL;
 568                         }
 569                         cmd->cb.data = NULL;
 570                 } else
 571                         imap->literal_pending = 1;
 572         } else if (cmd->cb.cont)
 573                 imap->literal_pending = 1;
 574         cmd->next = NULL;
 575         *imap->in_progress_append = cmd;
 576         imap->in_progress_append = &cmd->next;
 577         imap->num_in_progress++;
 578         return cmd;
 579 }
 580
 581 __attribute__((format (printf, 3, 4)))
 582 static int imap_exec(struct imap_store *ctx, struct imap_cmd_cb *cb,
 583                      const char *fmt, ...)
 584 {
 585         va_list ap;
 586         struct imap_cmd *cmdp;
 587
 588         va_start(ap, fmt);
 589         cmdp = issue_imap_cmd(ctx, cb, fmt, ap);
 590         va_end(ap);
 591         if (!cmdp)
 592                 return RESP_BAD;
 593
 594         return get_cmd_result(ctx, cmdp);
 595 }
 596
 597 __attribute__((format (printf, 3, 4)))
 598 static int imap_exec_m(struct imap_store *ctx, struct imap_cmd_cb *cb,
 599                        const char *fmt, ...)
 600 {
 601         va_list ap;
 602         struct imap_cmd *cmdp;
 603
 604         va_start(ap, fmt);
 605         cmdp = issue_imap_cmd(ctx, cb, fmt, ap);
 606         va_end(ap);
 607         if (!cmdp)
 608                 return DRV_STORE_BAD;
 609
 610         switch (get_cmd_result(ctx, cmdp)) {
 611         case RESP_BAD: return DRV_STORE_BAD;
 612         case RESP_NO: return DRV_MSG_BAD;
 613         default: return DRV_OK;
 614         }
 615 }
 616
 617 static int skip_imap_list_l(char **sp, int level)
 618 {
 619         char *s = *sp;
 620
 621         for (;;) {
 622                 while (isspace((unsigned char)*s))
 623                         s++;
 624                 if (level && *s == ')') {
 625                         s++;
 626                         break;
 627                 }
 628                 if (*s == '(') {
 629                         /* sublist */
 630                         s++;
 631                         if (skip_imap_list_l(&s, level + 1))
 632                                 goto bail;
 633                 } else if (*s == '"') {
 634                         /* quoted string */
 635                         s++;
 636                         for (; *s != '"'; s++)
 637                                 if (!*s)
 638                                         goto bail;
 639                         s++;
 640                 } else {
 641                         /* atom */
 642                         for (; *s && !isspace((unsigned char)*s); s++)
 643                                 if (level && *s == ')')
 644                                         break;
 645                 }
 646
 647                 if (!level)
 648                         break;
 649                 if (!*s)
 650                         goto bail;
 651         }
 652         *sp = s;
 653         return 0;
 654
 655 bail:
 656         return -1;
 657 }
 658
 659 static void skip_list(char **sp)
 660 {
 661         skip_imap_list_l(sp, 0);
 662 }
 663
 664 static void parse_capability(struct imap *imap, char *cmd)
 665 {
 666         char *arg;
 667         unsigned i;
 668
 669         imap->caps = 0x80000000;
 670         while ((arg = next_arg(&cmd)))
 671                 for (i = 0; i < ARRAY_SIZE(cap_list); i++)
 672                         if (!strcmp(cap_list[i], arg))
 673                                 imap->caps |= 1 << i;
 674         imap->rcaps = imap->caps;
 675 }
 676
 677 static int parse_response_code(struct imap_store *ctx, struct imap_cmd_cb *cb,
 678                                char *s)
 679 {
 680         struct imap *imap = ctx->imap;
 681         char *arg, *p;
 682
 683         if (!s || *s != '[')
 684                 return RESP_OK;         /* no response code */
 685         s++;
 686         if (!(p = strchr(s, ']'))) {
 687                 fprintf(stderr, "IMAP error: malformed response code\n");
 688                 return RESP_BAD;
 689         }
 690         *p++ = 0;
 691         arg = next_arg(&s);
 692         if (!arg) {
 693                 fprintf(stderr, "IMAP error: empty response code\n");
 694                 return RESP_BAD;
 695         }
 696         if (!strcmp("UIDVALIDITY", arg)) {
 697                 if (!(arg = next_arg(&s)) || !(ctx->uidvalidity = atoi(arg))) {
 698                         fprintf(stderr, "IMAP error: malformed UIDVALIDITY status\n");
 699                         return RESP_BAD;
 700                 }
 701         } else if (!strcmp("UIDNEXT", arg)) {
 702                 if (!(arg = next_arg(&s)) || !(imap->uidnext = atoi(arg))) {
 703                         fprintf(stderr, "IMAP error: malformed NEXTUID status\n");
 704                         return RESP_BAD;
 705                 }
 706         } else if (!strcmp("CAPABILITY", arg)) {
 707                 parse_capability(imap, s);
 708         } else if (!strcmp("ALERT", arg)) {
 709                 /* RFC2060 says that these messages MUST be displayed
 710                  * to the user
 711                  */
 712                 for (; isspace((unsigned char)*p); p++);
 713                 fprintf(stderr, "*** IMAP ALERT *** %s\n", p);
 714         } else if (cb && cb->ctx && !strcmp("APPENDUID", arg)) {
 715                 if (!(arg = next_arg(&s)) || !(ctx->uidvalidity = atoi(arg)) ||
 716                     !(arg = next_arg(&s)) || !(*(int *)cb->ctx = atoi(arg))) {
 717                         fprintf(stderr, "IMAP error: malformed APPENDUID status\n");
 718                         return RESP_BAD;
 719                 }
 720         }
 721         return RESP_OK;
 722 }
 723
 724 static int get_cmd_result(struct imap_store *ctx, struct imap_cmd *tcmd)
 725 {
 726         struct imap *imap = ctx->imap;
 727         struct imap_cmd *cmdp, **pcmdp;
 728         char *cmd;
 729         const char *arg, *arg1;
 730         int n, resp, resp2, tag;
 731
 732         for (;;) {
 733                 if (buffer_gets(&imap->buf, &cmd))
 734                         return RESP_BAD;
 735
 736                 arg = next_arg(&cmd);
 737                 if (!arg) {
 738                         fprintf(stderr, "IMAP error: empty response\n");
 739                         return RESP_BAD;
 740                 }
 741                 if (*arg == '*') {
 742                         arg = next_arg(&cmd);
 743                         if (!arg) {
 744                                 fprintf(stderr, "IMAP error: unable to parse untagged response\n");
 745                                 return RESP_BAD;
 746                         }
 747
 748                         if (!strcmp("NAMESPACE", arg)) {
 749                                 /* rfc2342 NAMESPACE response. */
 750                                 skip_list(&cmd); /* Personal mailboxes */
 751                                 skip_list(&cmd); /* Others' mailboxes */
 752                                 skip_list(&cmd); /* Shared mailboxes */
 753                         } else if (!strcmp("OK", arg) || !strcmp("BAD", arg) ||
 754                                    !strcmp("NO", arg) || !strcmp("BYE", arg)) {
 755                                 if ((resp = parse_response_code(ctx, NULL, cmd)) != RESP_OK)
 756                                         return resp;
 757                         } else if (!strcmp("CAPABILITY", arg)) {
 758                                 parse_capability(imap, cmd);
 759                         } else if ((arg1 = next_arg(&cmd))) {
 760                                 ; /*
 761                                    * Unhandled response-data with at least two words.
 762                                    * Ignore it.
 763                                    *
 764                                    * NEEDSWORK: Previously this case handled '<num> EXISTS'
 765                                    * and '<num> RECENT' but as a probably-unintended side
 766                                    * effect it ignores other unrecognized two-word
 767                                    * responses.  imap-send doesn't ever try to read
 768                                    * messages or mailboxes these days, so consider
 769                                    * eliminating this case.
 770                                    */
 771                         } else {
 772                                 fprintf(stderr, "IMAP error: unable to parse untagged response\n");
 773                                 return RESP_BAD;
 774                         }
 775                 } else if (!imap->in_progress) {
 776                         fprintf(stderr, "IMAP error: unexpected reply: %s %s\n", arg, cmd ? cmd : "");
 777                         return RESP_BAD;
 778                 } else if (*arg == '+') {
 779                         /* This can happen only with the last command underway, as
 780                            it enforces a round-trip. */
 781                         cmdp = (struct imap_cmd *)((char *)imap->in_progress_append -
 782                                offsetof(struct imap_cmd, next));
 783                         if (cmdp->cb.data) {
 784                                 n = socket_write(&imap->buf.sock, cmdp->cb.data, cmdp->cb.dlen);
 785                                 FREE_AND_NULL(cmdp->cb.data);
 786                                 if (n != (int)cmdp->cb.dlen)
 787                                         return RESP_BAD;
 788                         } else if (cmdp->cb.cont) {
 789                                 if (cmdp->cb.cont(ctx, cmd))
 790                                         return RESP_BAD;
 791                         } else {
 792                                 fprintf(stderr, "IMAP error: unexpected command continuation request\n");
 793                                 return RESP_BAD;
 794                         }
 795                         if (socket_write(&imap->buf.sock, "\r\n", 2) != 2)
 796                                 return RESP_BAD;
 797                         if (!cmdp->cb.cont)
 798                                 imap->literal_pending = 0;
 799                         if (!tcmd)
 800                                 return DRV_OK;
 801                 } else {
 802                         tag = atoi(arg);
 803                         for (pcmdp = &imap->in_progress; (cmdp = *pcmdp); pcmdp = &cmdp->next)
 804                                 if (cmdp->tag == tag)
 805                                         goto gottag;
 806                         fprintf(stderr, "IMAP error: unexpected tag %s\n", arg);
 807                         return RESP_BAD;
 808                 gottag:
 809                         if (!(*pcmdp = cmdp->next))
 810                                 imap->in_progress_append = pcmdp;
 811                         imap->num_in_progress--;
 812                         if (cmdp->cb.cont || cmdp->cb.data)
 813                                 imap->literal_pending = 0;
 814                         arg = next_arg(&cmd);
 815                         if (!arg)
 816                                 arg = "";
 817                         if (!strcmp("OK", arg))
 818                                 resp = DRV_OK;
 819                         else {
 820                                 if (!strcmp("NO", arg))
 821                                         resp = RESP_NO;
 822                                 else /*if (!strcmp("BAD", arg))*/
 823                                         resp = RESP_BAD;
 824                                 fprintf(stderr, "IMAP command '%s' returned response (%s) - %s\n",
 825                                         !starts_with(cmdp->cmd, "LOGIN") ?
 826                                                         cmdp->cmd : "LOGIN <user> <pass>",
 827                                                         arg, cmd ? cmd : "");
 828                         }
 829                         if ((resp2 = parse_response_code(ctx, &cmdp->cb, cmd)) > resp)
 830                                 resp = resp2;
 831                         free(cmdp->cb.data);
 832                         free(cmdp->cmd);
 833                         free(cmdp);
 834                         if (!tcmd || tcmd == cmdp)
 835                                 return resp;
 836                 }
 837         }
 838         /* not reached */
 839 }
 840
 841 static void imap_close_server(struct imap_store *ictx)
 842 {
 843         struct imap *imap = ictx->imap;
 844
 845         if (imap->buf.sock.fd[0] != -1) {
 846                 imap_exec(ictx, NULL, "LOGOUT");
 847                 socket_shutdown(&imap->buf.sock);
 848         }
 849         free(imap);
 850 }
 851
 852 static void imap_close_store(struct imap_store *ctx)
 853 {
 854         imap_close_server(ctx);
 855         free(ctx);
 856 }
 857
 858 #ifndef NO_OPENSSL
 859
 860 /*
 861  * hexchar() and cram() functions are based on the code from the isync
 862  * project (https://isync.sourceforge.io/).
 863  */
 864 static char hexchar(unsigned int b)
 865 {
 866         return b < 10 ? '0' + b : 'a' + (b - 10);
 867 }
 868
 869 #define ENCODED_SIZE(n) (4 * DIV_ROUND_UP((n), 3))
 870 static char *cram(const char *challenge_64, const char *user, const char *pass)
 871 {
 872         int i, resp_len, encoded_len, decoded_len;
 873         unsigned char hash[16];
 874         char hex[33];
 875         char *response, *response_64, *challenge;
 876
 877         /*
 878          * length of challenge_64 (i.e. base-64 encoded string) is a good
 879          * enough upper bound for challenge (decoded result).
 880          */
 881         encoded_len = strlen(challenge_64);
 882         challenge = xmalloc(encoded_len);
 883         decoded_len = EVP_DecodeBlock((unsigned char *)challenge,
 884                                       (unsigned char *)challenge_64, encoded_len);
 885         if (decoded_len < 0)
 886                 die("invalid challenge %s", challenge_64);
 887         if (!HMAC(EVP_md5(), pass, strlen(pass), (unsigned char *)challenge, decoded_len, hash, NULL))
 888                 die("HMAC error");
 889
 890         hex[32] = 0;
 891         for (i = 0; i < 16; i++) {
 892                 hex[2 * i] = hexchar((hash[i] >> 4) & 0xf);
 893                 hex[2 * i + 1] = hexchar(hash[i] & 0xf);
 894         }
 895
 896         /* response: "<user> <digest in hex>" */
 897         response = xstrfmt("%s %s", user, hex);
 898         resp_len = strlen(response);
 899
 900         response_64 = xmallocz(ENCODED_SIZE(resp_len));
 901         encoded_len = EVP_EncodeBlock((unsigned char *)response_64,
 902                                       (unsigned char *)response, resp_len);
 903         if (encoded_len < 0)
 904                 die("EVP_EncodeBlock error");
 905         return (char *)response_64;
 906 }
 907
 908 #else
 909
 910 static char *cram(const char *challenge_64 UNUSED,
 911                   const char *user UNUSED,
 912                   const char *pass UNUSED)
 913 {
 914         die("If you want to use CRAM-MD5 authenticate method, "
 915             "you have to build git-imap-send with OpenSSL library.");
 916 }
 917
 918 #endif
 919
 920 static int auth_cram_md5(struct imap_store *ctx, const char *prompt)
 921 {
 922         int ret;
 923         char *response;
 924
 925         response = cram(prompt, server.user, server.pass);
 926
 927         ret = socket_write(&ctx->imap->buf.sock, response, strlen(response));
 928         if (ret != strlen(response))
 929                 return error("IMAP error: sending response failed");
 930
 931         free(response);
 932
 933         return 0;
 934 }
 935
 936 static void server_fill_credential(struct imap_server_conf *srvc, struct credential *cred)
 937 {
 938         if (srvc->user && srvc->pass)
 939                 return;
 940
 941         cred->protocol = xstrdup(srvc->use_ssl ? "imaps" : "imap");
 942         cred->host = xstrdup(srvc->host);
 943
 944         cred->username = xstrdup_or_null(srvc->user);
 945         cred->password = xstrdup_or_null(srvc->pass);
 946
 947         credential_fill(cred);
 948
 949         if (!srvc->user)
 950                 srvc->user = xstrdup(cred->username);
 951         if (!srvc->pass)
 952                 srvc->pass = xstrdup(cred->password);
 953 }
 954
 955 static struct imap_store *imap_open_store(struct imap_server_conf *srvc, const char *folder)
 956 {
 957         struct credential cred = CREDENTIAL_INIT;
 958         struct imap_store *ctx;
 959         struct imap *imap;
 960         char *arg, *rsp;
 961         int s = -1, preauth;
 962
 963         CALLOC_ARRAY(ctx, 1);
 964
 965         ctx->imap = CALLOC_ARRAY(imap, 1);
 966         imap->buf.sock.fd[0] = imap->buf.sock.fd[1] = -1;
 967         imap->in_progress_append = &imap->in_progress;
 968
 969         /* open connection to IMAP server */
 970
 971         if (srvc->tunnel) {
 972                 struct child_process tunnel = CHILD_PROCESS_INIT;
 973
 974                 imap_info("Starting tunnel '%s'... ", srvc->tunnel);
 975
 976                 strvec_push(&tunnel.args, srvc->tunnel);
 977                 tunnel.use_shell = 1;
 978                 tunnel.in = -1;
 979                 tunnel.out = -1;
 980                 if (start_command(&tunnel))
 981                         die("cannot start proxy %s", srvc->tunnel);
 982
 983                 imap->buf.sock.fd[0] = tunnel.out;
 984                 imap->buf.sock.fd[1] = tunnel.in;
 985
 986                 imap_info("ok\n");
 987         } else {
 988 #ifndef NO_IPV6
 989                 struct addrinfo hints, *ai0, *ai;
 990                 int gai;
 991                 char portstr[6];
 992
 993                 xsnprintf(portstr, sizeof(portstr), "%d", srvc->port);
 994
 995                 memset(&hints, 0, sizeof(hints));
 996                 hints.ai_socktype = SOCK_STREAM;
 997                 hints.ai_protocol = IPPROTO_TCP;
 998
 999                 imap_info("Resolving %s... ", srvc->host);
1000                 gai = getaddrinfo(srvc->host, portstr, &hints, &ai);
1001                 if (gai) {
1002                         fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(gai));
1003                         goto bail;
1004                 }
1005                 imap_info("ok\n");
1006
1007                 for (ai0 = ai; ai; ai = ai->ai_next) {
1008                         char addr[NI_MAXHOST];
1009
1010                         s = socket(ai->ai_family, ai->ai_socktype,
1011                                    ai->ai_protocol);
1012                         if (s < 0)
1013                                 continue;
1014
1015                         getnameinfo(ai->ai_addr, ai->ai_addrlen, addr,
1016                                     sizeof(addr), NULL, 0, NI_NUMERICHOST);
1017                         imap_info("Connecting to [%s]:%s... ", addr, portstr);
1018
1019                         if (connect(s, ai->ai_addr, ai->ai_addrlen) < 0) {
1020                                 close(s);
1021                                 s = -1;
1022                                 perror("connect");
1023                                 continue;
1024                         }
1025
1026                         break;
1027                 }
1028                 freeaddrinfo(ai0);
1029 #else /* NO_IPV6 */
1030                 struct hostent *he;
1031                 struct sockaddr_in addr;
1032
1033                 memset(&addr, 0, sizeof(addr));
1034                 addr.sin_port = htons(srvc->port);
1035                 addr.sin_family = AF_INET;
1036
1037                 imap_info("Resolving %s... ", srvc->host);
1038                 he = gethostbyname(srvc->host);
1039                 if (!he) {
1040                         perror("gethostbyname");
1041                         goto bail;
1042                 }
1043                 imap_info("ok\n");
1044
1045                 addr.sin_addr.s_addr = *((int *) he->h_addr_list[0]);
1046
1047                 s = socket(PF_INET, SOCK_STREAM, 0);
1048
1049                 imap_info("Connecting to %s:%hu... ", inet_ntoa(addr.sin_addr), ntohs(addr.sin_port));
1050                 if (connect(s, (struct sockaddr *)&addr, sizeof(addr))) {
1051                         close(s);
1052                         s = -1;
1053                         perror("connect");
1054                 }
1055 #endif
1056                 if (s < 0) {
1057                         fputs("Error: unable to connect to server.\n", stderr);
1058                         goto bail;
1059                 }
1060
1061                 imap->buf.sock.fd[0] = s;
1062                 imap->buf.sock.fd[1] = dup(s);
1063
1064                 if (srvc->use_ssl &&
1065                     ssl_socket_connect(&imap->buf.sock, 0, srvc->ssl_verify)) {
1066                         close(s);
1067                         goto bail;
1068                 }
1069                 imap_info("ok\n");
1070         }
1071
1072         /* read the greeting string */
1073         if (buffer_gets(&imap->buf, &rsp)) {
1074                 fprintf(stderr, "IMAP error: no greeting response\n");
1075                 goto bail;
1076         }
1077         arg = next_arg(&rsp);
1078         if (!arg || *arg != '*' || (arg = next_arg(&rsp)) == NULL) {
1079                 fprintf(stderr, "IMAP error: invalid greeting response\n");
1080                 goto bail;
1081         }
1082         preauth = 0;
1083         if (!strcmp("PREAUTH", arg))
1084                 preauth = 1;
1085         else if (strcmp("OK", arg) != 0) {
1086                 fprintf(stderr, "IMAP error: unknown greeting response\n");
1087                 goto bail;
1088         }
1089         parse_response_code(ctx, NULL, rsp);
1090         if (!imap->caps && imap_exec(ctx, NULL, "CAPABILITY") != RESP_OK)
1091                 goto bail;
1092
1093         if (!preauth) {
1094 #ifndef NO_OPENSSL
1095                 if (!srvc->use_ssl && CAP(STARTTLS)) {
1096                         if (imap_exec(ctx, NULL, "STARTTLS") != RESP_OK)
1097                                 goto bail;
1098                         if (ssl_socket_connect(&imap->buf.sock, 1,
1099                                                srvc->ssl_verify))
1100                                 goto bail;
1101                         /* capabilities may have changed, so get the new capabilities */
1102                         if (imap_exec(ctx, NULL, "CAPABILITY") != RESP_OK)
1103                                 goto bail;
1104                 }
1105 #endif
1106                 imap_info("Logging in...\n");
1107                 server_fill_credential(srvc, &cred);
1108
1109                 if (srvc->auth_method) {
1110                         struct imap_cmd_cb cb;
1111
1112                         if (!strcmp(srvc->auth_method, "CRAM-MD5")) {
1113                                 if (!CAP(AUTH_CRAM_MD5)) {
1114                                         fprintf(stderr, "You specified "
1115                                                 "CRAM-MD5 as authentication method, "
1116                                                 "but %s doesn't support it.\n", srvc->host);
1117                                         goto bail;
1118                                 }
1119                                 /* CRAM-MD5 */
1120
1121                                 memset(&cb, 0, sizeof(cb));
1122                                 cb.cont = auth_cram_md5;
1123                                 if (imap_exec(ctx, &cb, "AUTHENTICATE CRAM-MD5") != RESP_OK) {
1124                                         fprintf(stderr, "IMAP error: AUTHENTICATE CRAM-MD5 failed\n");
1125                                         goto bail;
1126                                 }
1127                         } else {
1128                                 fprintf(stderr, "Unknown authentication method:%s\n", srvc->host);
1129                                 goto bail;
1130                         }
1131                 } else {
1132                         if (CAP(NOLOGIN)) {
1133                                 fprintf(stderr, "Skipping account %s@%s, server forbids LOGIN\n",
1134                                         srvc->user, srvc->host);
1135                                 goto bail;
1136                         }
1137                         if (!imap->buf.sock.ssl)
1138                                 imap_warn("*** IMAP Warning *** Password is being "
1139                                           "sent in the clear\n");
1140                         if (imap_exec(ctx, NULL, "LOGIN \"%s\" \"%s\"", srvc->user, srvc->pass) != RESP_OK) {
1141                                 fprintf(stderr, "IMAP error: LOGIN failed\n");
1142                                 goto bail;
1143                         }
1144                 }
1145         } /* !preauth */
1146
1147         if (cred.username)
1148                 credential_approve(&cred);
1149         credential_clear(&cred);
1150
1151         /* check the target mailbox exists */
1152         ctx->name = folder;
1153         switch (imap_exec(ctx, NULL, "EXAMINE \"%s\"", ctx->name)) {
1154         case RESP_OK:
1155                 /* ok */
1156                 break;
1157         case RESP_BAD:
1158                 fprintf(stderr, "IMAP error: could not check mailbox\n");
1159                 goto out;
1160         case RESP_NO:
1161                 if (imap_exec(ctx, NULL, "CREATE \"%s\"", ctx->name) == RESP_OK) {
1162                         imap_info("Created missing mailbox\n");
1163                 } else {
1164                         fprintf(stderr, "IMAP error: could not create missing mailbox\n");
1165                         goto out;
1166                 }
1167                 break;
1168         }
1169
1170         ctx->prefix = "";
1171         return ctx;
1172
1173 bail:
1174         if (cred.username)
1175                 credential_reject(&cred);
1176         credential_clear(&cred);
1177
1178  out:
1179         imap_close_store(ctx);
1180         return NULL;
1181 }
1182
1183 /*
1184  * Insert CR characters as necessary in *msg to ensure that every LF
1185  * character in *msg is preceded by a CR.
1186  */
1187 static void lf_to_crlf(struct strbuf *msg)
1188 {
1189         char *new_msg;
1190         size_t i, j;
1191         char lastc;
1192
1193         /* First pass: tally, in j, the size of the new_msg string: */
1194         for (i = j = 0, lastc = '\0'; i < msg->len; i++) {
1195                 if (msg->buf[i] == '\n' && lastc != '\r')
1196                         j++; /* a CR will need to be added here */
1197                 lastc = msg->buf[i];
1198                 j++;
1199         }
1200
1201         new_msg = xmallocz(j);
1202
1203         /*
1204          * Second pass: write the new_msg string.  Note that this loop is
1205          * otherwise identical to the first pass.
1206          */
1207         for (i = j = 0, lastc = '\0'; i < msg->len; i++) {
1208                 if (msg->buf[i] == '\n' && lastc != '\r')
1209                         new_msg[j++] = '\r';
1210                 lastc = new_msg[j++] = msg->buf[i];
1211         }
1212         strbuf_attach(msg, new_msg, j, j + 1);
1213 }
1214
1215 /*
1216  * Store msg to IMAP.  Also detach and free the data from msg->data,
1217  * leaving msg->data empty.
1218  */
1219 static int imap_store_msg(struct imap_store *ctx, struct strbuf *msg)
1220 {
1221         struct imap *imap = ctx->imap;
1222         struct imap_cmd_cb cb;
1223         const char *prefix, *box;
1224         int ret;
1225
1226         lf_to_crlf(msg);
1227         memset(&cb, 0, sizeof(cb));
1228
1229         cb.dlen = msg->len;
1230         cb.data = strbuf_detach(msg, NULL);
1231
1232         box = ctx->name;
1233         prefix = !strcmp(box, "INBOX") ? "" : ctx->prefix;
1234         ret = imap_exec_m(ctx, &cb, "APPEND \"%s%s\" ", prefix, box);
1235         imap->caps = imap->rcaps;
1236         if (ret != DRV_OK)
1237                 return ret;
1238
1239         return DRV_OK;
1240 }
1241
1242 static void wrap_in_html(struct strbuf *msg)
1243 {
1244         struct strbuf buf = STRBUF_INIT;
1245         static char *content_type = "Content-Type: text/html;\n";
1246         static char *pre_open = "<pre>\n";
1247         static char *pre_close = "</pre>\n";
1248         const char *body = strstr(msg->buf, "\n\n");
1249
1250         if (!body)
1251                 return; /* Headers but no body; no wrapping needed */
1252
1253         body += 2;
1254
1255         strbuf_add(&buf, msg->buf, body - msg->buf - 1);
1256         strbuf_addstr(&buf, content_type);
1257         strbuf_addch(&buf, '\n');
1258         strbuf_addstr(&buf, pre_open);
1259         strbuf_addstr_xml_quoted(&buf, body);
1260         strbuf_addstr(&buf, pre_close);
1261
1262         strbuf_release(msg);
1263         *msg = buf;
1264 }
1265
1266 static int count_messages(struct strbuf *all_msgs)
1267 {
1268         int count = 0;
1269         char *p = all_msgs->buf;
1270
1271         while (1) {
1272                 if (starts_with(p, "From ")) {
1273                         p = strstr(p+5, "\nFrom: ");
1274                         if (!p) break;
1275                         p = strstr(p+7, "\nDate: ");
1276                         if (!p) break;
1277                         p = strstr(p+7, "\nSubject: ");
1278                         if (!p) break;
1279                         p += 10;
1280                         count++;
1281                 }
1282                 p = strstr(p+5, "\nFrom ");
1283                 if (!p)
1284                         break;
1285                 p++;
1286         }
1287         return count;
1288 }
1289
1290 /*
1291  * Copy the next message from all_msgs, starting at offset *ofs, to
1292  * msg.  Update *ofs to the start of the following message.  Return
1293  * true iff a message was successfully copied.
1294  */
1295 static int split_msg(struct strbuf *all_msgs, struct strbuf *msg, int *ofs)
1296 {
1297         char *p, *data;
1298         size_t len;
1299
1300         if (*ofs >= all_msgs->len)
1301                 return 0;
1302
1303         data = &all_msgs->buf[*ofs];
1304         len = all_msgs->len - *ofs;
1305
1306         if (len < 5 || !starts_with(data, "From "))
1307                 return 0;
1308
1309         p = strchr(data, '\n');
1310         if (p) {
1311                 p++;
1312                 len -= p - data;
1313                 *ofs += p - data;
1314                 data = p;
1315         }
1316
1317         p = strstr(data, "\nFrom ");
1318         if (p)
1319                 len = &p[1] - data;
1320
1321         strbuf_add(msg, data, len);
1322         *ofs += len;
1323         return 1;
1324 }
1325
1326 static int git_imap_config(const char *var, const char *val,
1327                            const struct config_context *ctx, void *cb)
1328 {
1329
1330         if (!strcmp("imap.sslverify", var))
1331                 server.ssl_verify = git_config_bool(var, val);
1332         else if (!strcmp("imap.preformattedhtml", var))
1333                 server.use_html = git_config_bool(var, val);
1334         else if (!strcmp("imap.folder", var))
1335                 return git_config_string(&server.folder, var, val);
1336         else if (!strcmp("imap.user", var))
1337                 return git_config_string(&server.user, var, val);
1338         else if (!strcmp("imap.pass", var))
1339                 return git_config_string(&server.pass, var, val);
1340         else if (!strcmp("imap.tunnel", var))
1341                 return git_config_string(&server.tunnel, var, val);
1342         else if (!strcmp("imap.authmethod", var))
1343                 return git_config_string(&server.auth_method, var, val);
1344         else if (!strcmp("imap.port", var))
1345                 server.port = git_config_int(var, val, ctx->kvi);
1346         else if (!strcmp("imap.host", var)) {
1347                 if (!val) {
1348                         return config_error_nonbool(var);
1349                 } else {
1350                         if (starts_with(val, "imap:"))
1351                                 val += 5;
1352                         else if (starts_with(val, "imaps:")) {
1353                                 val += 6;
1354                                 server.use_ssl = 1;
1355                         }
1356                         if (starts_with(val, "//"))
1357                                 val += 2;
1358                         server.host = xstrdup(val);
1359                 }
1360         } else
1361                 return git_default_config(var, val, ctx, cb);
1362
1363         return 0;
1364 }
1365
1366 static int append_msgs_to_imap(struct imap_server_conf *server,
1367                                struct strbuf* all_msgs, int total)
1368 {
1369         struct strbuf msg = STRBUF_INIT;
1370         struct imap_store *ctx = NULL;
1371         int ofs = 0;
1372         int r;
1373         int n = 0;
1374
1375         ctx = imap_open_store(server, server->folder);
1376         if (!ctx) {
1377                 fprintf(stderr, "failed to open store\n");
1378                 return 1;
1379         }
1380         ctx->name = server->folder;
1381
1382         fprintf(stderr, "sending %d message%s\n", total, (total != 1) ? "s" : "");
1383         while (1) {
1384                 unsigned percent = n * 100 / total;
1385
1386                 fprintf(stderr, "%4u%% (%d/%d) done\r", percent, n, total);
1387
1388                 if (!split_msg(all_msgs, &msg, &ofs))
1389                         break;
1390                 if (server->use_html)
1391                         wrap_in_html(&msg);
1392                 r = imap_store_msg(ctx, &msg);
1393                 if (r != DRV_OK)
1394                         break;
1395                 n++;
1396         }
1397         fprintf(stderr, "\n");
1398
1399         imap_close_store(ctx);
1400
1401         return 0;
1402 }
1403
1404 #ifdef USE_CURL_FOR_IMAP_SEND
1405 static CURL *setup_curl(struct imap_server_conf *srvc, struct credential *cred)
1406 {
1407         CURL *curl;
1408         struct strbuf path = STRBUF_INIT;
1409         char *uri_encoded_folder;
1410
1411         if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK)
1412                 die("curl_global_init failed");
1413
1414         curl = curl_easy_init();
1415
1416         if (!curl)
1417                 die("curl_easy_init failed");
1418
1419         server_fill_credential(srvc, cred);
1420         curl_easy_setopt(curl, CURLOPT_USERNAME, srvc->user);
1421         curl_easy_setopt(curl, CURLOPT_PASSWORD, srvc->pass);
1422
1423         strbuf_addstr(&path, srvc->use_ssl ? "imaps://" : "imap://");
1424         strbuf_addstr(&path, srvc->host);
1425         if (!path.len || path.buf[path.len - 1] != '/')
1426                 strbuf_addch(&path, '/');
1427
1428         uri_encoded_folder = curl_easy_escape(curl, srvc->folder, 0);
1429         if (!uri_encoded_folder)
1430                 die("failed to encode server folder");
1431         strbuf_addstr(&path, uri_encoded_folder);
1432         curl_free(uri_encoded_folder);
1433
1434         curl_easy_setopt(curl, CURLOPT_URL, path.buf);
1435         strbuf_release(&path);
1436         curl_easy_setopt(curl, CURLOPT_PORT, srvc->port);
1437
1438         if (srvc->auth_method) {
1439 #ifndef GIT_CURL_HAVE_CURLOPT_LOGIN_OPTIONS
1440                 warning("No LOGIN_OPTIONS support in this cURL version");
1441 #else
1442                 struct strbuf auth = STRBUF_INIT;
1443                 strbuf_addstr(&auth, "AUTH=");
1444                 strbuf_addstr(&auth, srvc->auth_method);
1445                 curl_easy_setopt(curl, CURLOPT_LOGIN_OPTIONS, auth.buf);
1446                 strbuf_release(&auth);
1447 #endif
1448         }
1449
1450         if (!srvc->use_ssl)
1451                 curl_easy_setopt(curl, CURLOPT_USE_SSL, (long)CURLUSESSL_TRY);
1452
1453         curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, srvc->ssl_verify);
1454         curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, srvc->ssl_verify);
1455
1456         curl_easy_setopt(curl, CURLOPT_READFUNCTION, fread_buffer);
1457
1458         curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);
1459
1460         if (0 < verbosity || getenv("GIT_CURL_VERBOSE"))
1461                 http_trace_curl_no_data();
1462         setup_curl_trace(curl);
1463
1464         return curl;
1465 }
1466
1467 static int curl_append_msgs_to_imap(struct imap_server_conf *server,
1468                                     struct strbuf* all_msgs, int total)
1469 {
1470         int ofs = 0;
1471         int n = 0;
1472         struct buffer msgbuf = { STRBUF_INIT, 0 };
1473         CURL *curl;
1474         CURLcode res = CURLE_OK;
1475         struct credential cred = CREDENTIAL_INIT;
1476
1477         curl = setup_curl(server, &cred);
1478         curl_easy_setopt(curl, CURLOPT_READDATA, &msgbuf);
1479
1480         fprintf(stderr, "sending %d message%s\n", total, (total != 1) ? "s" : "");
1481         while (1) {
1482                 unsigned percent = n * 100 / total;
1483                 int prev_len;
1484
1485                 fprintf(stderr, "%4u%% (%d/%d) done\r", percent, n, total);
1486
1487                 prev_len = msgbuf.buf.len;
1488                 if (!split_msg(all_msgs, &msgbuf.buf, &ofs))
1489                         break;
1490                 if (server->use_html)
1491                         wrap_in_html(&msgbuf.buf);
1492                 lf_to_crlf(&msgbuf.buf);
1493
1494                 curl_easy_setopt(curl, CURLOPT_INFILESIZE_LARGE,
1495                                  (curl_off_t)(msgbuf.buf.len-prev_len));
1496
1497                 res = curl_easy_perform(curl);
1498
1499                 if(res != CURLE_OK) {
1500                         fprintf(stderr, "curl_easy_perform() failed: %s\n",
1501                                         curl_easy_strerror(res));
1502                         break;
1503                 }
1504
1505                 n++;
1506         }
1507         fprintf(stderr, "\n");
1508
1509         curl_easy_cleanup(curl);
1510         curl_global_cleanup();
1511
1512         if (cred.username) {
1513                 if (res == CURLE_OK)
1514                         credential_approve(&cred);
1515                 else if (res == CURLE_LOGIN_DENIED)
1516                         credential_reject(&cred);
1517         }
1518
1519         credential_clear(&cred);
1520
1521         return res != CURLE_OK;
1522 }
1523 #endif
1524
1525 int cmd_main(int argc, const char **argv)
1526 {
1527         struct strbuf all_msgs = STRBUF_INIT;
1528         int total;
1529         int nongit_ok;
1530
1531         setup_git_directory_gently(&nongit_ok);
1532         git_config(git_imap_config, NULL);
1533
1534         argc = parse_options(argc, (const char **)argv, "", imap_send_options, imap_send_usage, 0);
1535
1536         if (argc)
1537                 usage_with_options(imap_send_usage, imap_send_options);
1538
1539 #ifndef USE_CURL_FOR_IMAP_SEND
1540         if (use_curl) {
1541                 warning("--curl not supported in this build");
1542                 use_curl = 0;
1543         }
1544 #elif defined(NO_OPENSSL)
1545         if (!use_curl) {
1546                 warning("--no-curl not supported in this build");
1547                 use_curl = 1;
1548         }
1549 #endif
1550
1551         if (!server.port)
1552                 server.port = server.use_ssl ? 993 : 143;
1553
1554         if (!server.folder) {
1555                 fprintf(stderr, "no imap store specified\n");
1556                 return 1;
1557         }
1558         if (!server.host) {
1559                 if (!server.tunnel) {
1560                         fprintf(stderr, "no imap host specified\n");
1561                         return 1;
1562                 }
1563                 server.host = "tunnel";
1564         }
1565
1566         /* read the messages */
1567         if (strbuf_read(&all_msgs, 0, 0) < 0) {
1568                 error_errno(_("could not read from stdin"));
1569                 return 1;
1570         }
1571
1572         if (all_msgs.len == 0) {
1573                 fprintf(stderr, "nothing to send\n");
1574                 return 1;
1575         }
1576
1577         total = count_messages(&all_msgs);
1578         if (!total) {
1579                 fprintf(stderr, "no messages to send\n");
1580                 return 1;
1581         }
1582
1583         /* write it to the imap server */
1584
1585         if (server.tunnel)
1586                 return append_msgs_to_imap(&server, &all_msgs, total);
1587
1588 #ifdef USE_CURL_FOR_IMAP_SEND
1589         if (use_curl)
1590                 return curl_append_msgs_to_imap(&server, &all_msgs, total);
1591 #endif
1592
1593         return append_msgs_to_imap(&server, &all_msgs, total);
1594 }