src/lib/quickmail.cc

   1 /*
   2     This file is part of libquickmail.
   3
   4     libquickmail is free software: you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation, either version 3 of the License, or
   7     (at your option) any later version.
   8
   9     libquickmail is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with libquickmail.  If not, see <http://www.gnu.org/licenses/>.
  16 */
  17
  18 #include "quickmail.h"
  19 #include <stdlib.h>
  20 #include <stdio.h>
  21 #include <string.h>
  22 #include <time.h>
  23 #ifndef _WIN32
  24 #include <unistd.h>
  25 #endif
  26 #include <curl/curl.h>
  27
  28 #define NEWLINE "\r\n"
  29 #define NEWLINELENGTH 2
  30
  31 #define MIME_LINE_WIDTH 72
  32 #define BODY_BUFFER_SIZE 256
  33
  34 //definitions of the differen stages of generating the message data
  35 #define MAILPART_INITIALIZE 0
  36 #define MAILPART_HEADER     1
  37 #define MAILPART_BODY       2
  38 #define MAILPART_BODY_DONE  3
  39 #define MAILPART_ATTACHMENT 4
  40 #define MAILPART_END        5
  41 #define MAILPART_DONE       6
  42
  43 static const char* default_mime_type = "text/plain";
  44
  45 ////////////////////////////////////////////////////////////////////////
  46
  47 #define DEBUG_ERROR(errmsg)
  48 static const char* ERRMSG_MEMORY_ALLOCATION_ERROR = "Memory allocation error";
  49
  50 ////////////////////////////////////////////////////////////////////////
  51
  52 char* randomize_zeros (char* data)
  53 {
  54   //replace all 0s with random digits
  55   char* p = data;
  56   while (*p) {
  57     if (*p == '0')
  58       *p = '0' + rand() % 10;
  59     p++;
  60   }
  61   return data;
  62 }
  63
  64 char* str_append (char** data, const char* newdata)
  65 {
  66   //append a string to the end of an existing string
  67   char* p;
  68   int len = (*data ? strlen(*data) : 0);
  69   if ((p = (char*)realloc(*data, len + strlen(newdata) + 1)) == NULL) {
  70     free(p);
  71     DEBUG_ERROR(ERRMSG_MEMORY_ALLOCATION_ERROR)
  72     return NULL;
  73   }
  74   *data = p;
  75   strcpy(*data + len, newdata);
  76   return *data;
  77 }
  78
  79 ////////////////////////////////////////////////////////////////////////
  80
  81 struct email_info_struct {
  82   int current;  //must be zet to 0
  83   time_t timestamp;
  84   char* from;
  85   struct email_info_email_list_struct* to;
  86   struct email_info_email_list_struct* cc;
  87   struct email_info_email_list_struct* bcc;
  88   char* subject;
  89   char* header;
  90   struct email_info_attachment_list_struct* bodylist;
  91   struct email_info_attachment_list_struct* attachmentlist;
  92   char* buf;
  93   int buflen;
  94   char* mime_boundary_body;
  95   char* mime_boundary_part;
  96   struct email_info_attachment_list_struct* current_attachment;
  97   FILE* debuglog;
  98   char dtable[64];
  99 };
 100
 101 ////////////////////////////////////////////////////////////////////////
 102
 103 struct email_info_email_list_struct {
 104   char* data;
 105   struct email_info_email_list_struct* next;
 106 };
 107
 108 void email_info_string_list_add (struct email_info_email_list_struct** list, const char* data)
 109 {
 110   struct email_info_email_list_struct** p = list;
 111   while (*p)
 112     p = &(*p)->next;
 113   if ((*p = (struct email_info_email_list_struct*)malloc(sizeof(struct email_info_email_list_struct))) == NULL) {
 114     DEBUG_ERROR(ERRMSG_MEMORY_ALLOCATION_ERROR)
 115     return;
 116   }
 117   (*p)->data = (data ? strdup(data) : NULL);
 118   (*p)->next = NULL;
 119 }
 120
 121 void email_info_string_list_free (struct email_info_email_list_struct** list)
 122 {
 123   struct email_info_email_list_struct* p = *list;
 124   struct email_info_email_list_struct* current;
 125   while (p) {
 126     current = p;
 127     p = current->next;
 128     free(current->data);
 129     free(current);
 130   }
 131   *list = NULL;
 132 }
 133
 134 char* email_info_string_list_concatenate (struct email_info_email_list_struct* list)
 135 {
 136   char* result = NULL;
 137   struct email_info_email_list_struct* listentry = list;
 138   while (listentry) {
 139     if (listentry->data && *listentry->data) {
 140       if (result)
 141         str_append(&result, "," NEWLINE "\t");
 142       str_append(&result, "<");
 143       str_append(&result, listentry->data);
 144       str_append(&result, ">");
 145     }
 146     listentry = listentry->next;
 147   }
 148   return result;
 149 }
 150
 151 ////////////////////////////////////////////////////////////////////////
 152
 153 struct email_info_attachment_list_struct {
 154   char* filename;
 155   char* mimetype;
 156   void* filedata;
 157   void* handle;
 158   quickmail_attachment_open_fn email_info_attachment_open;
 159   quickmail_attachment_read_fn email_info_attachment_read;
 160   quickmail_attachment_close_fn email_info_attachment_close;
 161   quickmail_attachment_free_filedata_fn email_info_attachment_filedata_free;
 162   struct email_info_attachment_list_struct* next;
 163 };
 164
 165 struct email_info_attachment_list_struct* email_info_attachment_list_add (struct email_info_attachment_list_struct** list, const char* filename, const char* mimetype, void* filedata, quickmail_attachment_open_fn email_info_attachment_open, quickmail_attachment_read_fn email_info_attachment_read, quickmail_attachment_close_fn email_info_attachment_close, quickmail_attachment_free_filedata_fn email_info_attachment_filedata_free)
 166 {
 167   struct email_info_attachment_list_struct** p = list;
 168   while (*p)
 169     p = &(*p)->next;
 170   if ((*p = (struct email_info_attachment_list_struct*)malloc(sizeof(struct email_info_attachment_list_struct))) == NULL) {
 171     DEBUG_ERROR(ERRMSG_MEMORY_ALLOCATION_ERROR)
 172     return NULL;
 173   }
 174   (*p)->filename = strdup(filename ? filename : "UNNAMED");
 175   (*p)->mimetype = (mimetype ? strdup(mimetype) : NULL);
 176   (*p)->filedata = filedata;
 177   (*p)->handle = NULL;
 178   (*p)->email_info_attachment_open = email_info_attachment_open;
 179   (*p)->email_info_attachment_read = email_info_attachment_read;
 180   (*p)->email_info_attachment_close = email_info_attachment_close;
 181   (*p)->email_info_attachment_filedata_free = email_info_attachment_filedata_free;
 182   (*p)->next = NULL;
 183   return *p;
 184 }
 185
 186 void email_info_attachment_list_free_entry (struct email_info_attachment_list_struct* current)
 187 {
 188   if (current->handle) {
 189     if (current->email_info_attachment_close)
 190       current->email_info_attachment_close(current->handle);
 191     //else
 192     //  free(current->handle);
 193     current->handle = NULL;
 194   }
 195   if (current->filedata) {
 196     if (current->email_info_attachment_filedata_free)
 197       current->email_info_attachment_filedata_free(current->filedata);
 198     else
 199       free(current->filedata);
 200   }
 201   if (current->mimetype)
 202     free(current->mimetype);
 203   free(current->filename);
 204   free(current);
 205 }
 206
 207 void email_info_attachment_list_free (struct email_info_attachment_list_struct** list)
 208 {
 209   struct email_info_attachment_list_struct* p = *list;
 210   struct email_info_attachment_list_struct* current;
 211   while (p) {
 212     current = p;
 213     p = current->next;
 214     email_info_attachment_list_free_entry(current);
 215   }
 216   *list = NULL;
 217 }
 218
 219 int email_info_attachment_list_delete (struct email_info_attachment_list_struct** list, const char* filename)
 220 {
 221   struct email_info_attachment_list_struct** p = list;
 222   while (*p) {
 223     if (strcmp((*p)->filename, filename) == 0) {
 224       struct email_info_attachment_list_struct* current = *p;
 225       *p = current->next;
 226       email_info_attachment_list_free_entry(current);
 227       return 0;
 228     }
 229     p = &(*p)->next;
 230   }
 231   return -1;
 232 }
 233
 234 void email_info_attachment_list_close_handles (struct email_info_attachment_list_struct* list)
 235 {
 236   struct email_info_attachment_list_struct* p = list;
 237   while (p) {
 238     if (p->handle) {
 239       if (p->email_info_attachment_close)
 240         p->email_info_attachment_close(p->handle);
 241       //else
 242       //  free(p->handle);
 243       p->handle = NULL;
 244     }
 245     p = p->next;
 246   }
 247 }
 248
 249 //dummy attachment functions
 250
 251 void* email_info_attachment_open_dummy (void *)
 252 {
 253         return (void *) &email_info_attachment_open_dummy;
 254 }
 255
 256 size_t email_info_attachment_read_dummy (void *, void *, size_t)
 257 {
 258   return 0;
 259 }
 260
 261 struct email_info_attachment_list_struct* email_info_attachment_list_add_dummy (struct email_info_attachment_list_struct** list, const char* filename, const char* mimetype)
 262 {
 263   return email_info_attachment_list_add(list, filename, mimetype, NULL, email_info_attachment_open_dummy, email_info_attachment_read_dummy, NULL, NULL);
 264 }
 265
 266 //file attachment functions
 267
 268 void* email_info_attachment_open_file (void* filedata)
 269 {
 270   return (void*)fopen((char*)filedata, "rb");
 271 }
 272
 273 size_t email_info_attachment_read_file (void* handle, void* buf, size_t len)
 274 {
 275   return fread(buf, 1, len, (FILE*)handle);
 276 }
 277
 278 void email_info_attachment_close_file (void* handle)
 279 {
 280   if (handle)
 281     fclose((FILE*)handle);
 282 }
 283
 284 struct email_info_attachment_list_struct* email_info_attachment_list_add_file (struct email_info_attachment_list_struct** list, const char* path, const char* mimetype)
 285 {
 286   //determine base filename
 287   const char* basename = path + strlen(path);
 288   while (basename != path) {
 289     basename--;
 290     if (*basename == '/'
 291 #ifdef _WIN32
 292         || *basename == '\\' || *basename == ':'
 293 #endif
 294     ) {
 295       basename++;
 296       break;
 297     }
 298   }
 299   return email_info_attachment_list_add(list, basename, mimetype, (void*)strdup(path), email_info_attachment_open_file, email_info_attachment_read_file, email_info_attachment_close_file, NULL);
 300 }
 301
 302 //memory attachment functions
 303
 304 struct email_info_attachment_memory_filedata_struct {
 305   char* data;
 306   size_t datalen;
 307   int mustfree;
 308 };
 309
 310 struct email_info_attachment_memory_handle_struct {
 311   const char* data;
 312   size_t datalen;
 313   size_t pos;
 314 };
 315
 316 void* email_info_attachment_open_memory (void* filedata)
 317 {
 318   struct email_info_attachment_memory_filedata_struct* data;
 319   struct email_info_attachment_memory_handle_struct* result;
 320   data = ((struct email_info_attachment_memory_filedata_struct*)filedata);
 321   if (!data->data)
 322     return NULL;
 323   if ((result = (struct email_info_attachment_memory_handle_struct*)malloc(sizeof(struct email_info_attachment_memory_handle_struct))) == NULL) {
 324     DEBUG_ERROR(ERRMSG_MEMORY_ALLOCATION_ERROR)
 325     return NULL;
 326   }
 327   result->data = data->data;
 328   result->datalen = data->datalen;
 329   result->pos = 0;
 330   return result;
 331 }
 332
 333 size_t email_info_attachment_read_memory (void* handle, void* buf, size_t len)
 334 {
 335   struct email_info_attachment_memory_handle_struct* h = (struct email_info_attachment_memory_handle_struct*)handle;
 336   size_t n = (h->pos + len <= h->datalen ? len : h->datalen - h->pos);
 337   memcpy(buf, h->data + h->pos, n);
 338   h->pos += n;
 339   return n;
 340 }
 341
 342 void email_info_attachment_close_memory (void* handle)
 343 {
 344   if (handle)
 345     free(handle);
 346 }
 347
 348 void email_info_attachment_filedata_free_memory (void* filedata)
 349 {
 350   struct email_info_attachment_memory_filedata_struct* data = ((struct email_info_attachment_memory_filedata_struct*)filedata);
 351   if (data) {
 352     if (data->mustfree)
 353       free(data->data);
 354     free(data);
 355   }
 356 }
 357
 358 struct email_info_attachment_list_struct* email_info_attachment_list_add_memory (struct email_info_attachment_list_struct** list, const char* filename, const char* mimetype, char* data, size_t datalen, int mustfree)
 359 {
 360   struct email_info_attachment_memory_filedata_struct* filedata;
 361   if ((filedata = (struct email_info_attachment_memory_filedata_struct*)malloc(sizeof(struct email_info_attachment_memory_filedata_struct))) == NULL) {
 362     DEBUG_ERROR(ERRMSG_MEMORY_ALLOCATION_ERROR)
 363     return NULL;
 364   }
 365   filedata->data = data;
 366   filedata->datalen = datalen;
 367   filedata->mustfree = mustfree;
 368   return email_info_attachment_list_add(list, filename, mimetype, filedata, email_info_attachment_open_memory, email_info_attachment_read_memory, email_info_attachment_close_memory, email_info_attachment_filedata_free_memory);
 369 }
 370
 371 ////////////////////////////////////////////////////////////////////////
 372
 373 int quickmail_initialize ()
 374 {
 375   return 0;
 376 }
 377
 378 quickmail quickmail_create (const char* from, const char* subject)
 379 {
 380   int i;
 381   struct email_info_struct* mailobj;
 382   if ((mailobj = (struct email_info_struct*)malloc(sizeof(struct email_info_struct))) == NULL) {
 383     DEBUG_ERROR(ERRMSG_MEMORY_ALLOCATION_ERROR)
 384     return NULL;
 385   }
 386   mailobj->current = 0;
 387   mailobj->timestamp = time(NULL);
 388   mailobj->from = (from ? strdup(from) : NULL);
 389   mailobj->to = NULL;
 390   mailobj->cc = NULL;
 391   mailobj->bcc = NULL;
 392   mailobj->subject = (subject ? strdup(subject) : NULL);
 393   mailobj->header = NULL;
 394   mailobj->bodylist = NULL;
 395   mailobj->attachmentlist = NULL;
 396   mailobj->buf = NULL;
 397   mailobj->buflen = 0;
 398   mailobj->mime_boundary_body = NULL;
 399   mailobj->mime_boundary_part = NULL;
 400   mailobj->current_attachment = NULL;
 401   mailobj->debuglog = NULL;
 402   for (i = 0; i < 26; i++) {
 403     mailobj->dtable[i] = (char)('A' + i);
 404     mailobj->dtable[26 + i] = (char)('a' + i);
 405   }
 406   for (i = 0; i < 10; i++) {
 407     mailobj->dtable[52 + i] = (char)('0' + i);
 408   }
 409   mailobj->dtable[62] = '+';
 410   mailobj->dtable[63] = '/';
 411   srand(time(NULL));
 412   return mailobj;
 413 }
 414
 415 void quickmail_destroy (quickmail mailobj)
 416 {
 417   free(mailobj->from);
 418   email_info_string_list_free(&mailobj->to);
 419   email_info_string_list_free(&mailobj->cc);
 420   email_info_string_list_free(&mailobj->bcc);
 421   free(mailobj->subject);
 422   free(mailobj->header);
 423   email_info_attachment_list_free(&mailobj->bodylist);
 424   email_info_attachment_list_free(&mailobj->attachmentlist);
 425   free(mailobj->buf);
 426   free(mailobj->mime_boundary_body);
 427   free(mailobj->mime_boundary_part);
 428   free(mailobj);
 429 }
 430
 431 void quickmail_set_from (quickmail mailobj, const char* from)
 432 {
 433   free(mailobj->from);
 434   mailobj->from = strdup(from);
 435 }
 436
 437 const char* quickmail_get_from (quickmail mailobj)
 438 {
 439   return mailobj->from;
 440 }
 441
 442 void quickmail_add_to (quickmail mailobj, const char* email)
 443 {
 444   email_info_string_list_add(&mailobj->to, email);
 445 }
 446
 447 void quickmail_add_cc (quickmail mailobj, const char* email)
 448 {
 449   email_info_string_list_add(&mailobj->cc, email);
 450 }
 451
 452 void quickmail_add_bcc (quickmail mailobj, const char* email)
 453 {
 454   email_info_string_list_add(&mailobj->bcc, email);
 455 }
 456
 457 void quickmail_set_subject (quickmail mailobj, const char* subject)
 458 {
 459   free(mailobj->subject);
 460   mailobj->subject = (subject ? strdup(subject) : NULL);
 461 }
 462
 463 const char* quickmail_get_subject (quickmail mailobj)
 464 {
 465   return mailobj->subject;
 466 }
 467
 468 void quickmail_add_header (quickmail mailobj, const char* headerline)
 469 {
 470   str_append(&mailobj->header, headerline);
 471   str_append(&mailobj->header, NEWLINE);
 472 }
 473
 474 void quickmail_set_body (quickmail mailobj, const char* body)
 475 {
 476   email_info_attachment_list_free(&mailobj->bodylist);
 477   if (body)
 478     email_info_attachment_list_add_memory(&mailobj->bodylist, default_mime_type, default_mime_type, strdup(body), strlen(body), 1);
 479 }
 480
 481 char* quickmail_get_body (quickmail mailobj)
 482 {
 483   size_t n;
 484   char* p;
 485   char* result = NULL;
 486   size_t resultlen = 0;
 487   if (mailobj->bodylist && (mailobj->bodylist->handle = mailobj->bodylist->email_info_attachment_open(mailobj->bodylist->filedata)) != NULL) {
 488     do {
 489       if ((p = (char*)realloc(result, resultlen + BODY_BUFFER_SIZE)) == NULL) {
 490         free(result);
 491         DEBUG_ERROR(ERRMSG_MEMORY_ALLOCATION_ERROR)
 492         break;
 493       }
 494       result = p;
 495       if ((n = mailobj->bodylist->email_info_attachment_read(mailobj->bodylist->handle, result + resultlen, BODY_BUFFER_SIZE)) > 0)
 496         resultlen += n;
 497     } while (n > 0);
 498     if (mailobj->bodylist->email_info_attachment_close)
 499       mailobj->bodylist->email_info_attachment_close(mailobj->bodylist->handle);
 500     //else
 501     //  free(mailobj->bodylist->handle);
 502     mailobj->bodylist->handle = NULL;
 503   }
 504   return result;
 505 }
 506
 507 void quickmail_add_body_file (quickmail mailobj, const char* mimetype, const char* path)
 508 {
 509   email_info_attachment_list_add(&mailobj->bodylist, (mimetype ? mimetype : default_mime_type), (mimetype ? mimetype : default_mime_type), (void*)strdup(path), email_info_attachment_open_file, email_info_attachment_read_file, email_info_attachment_close_file, NULL);
 510 }
 511
 512 void quickmail_add_body_memory (quickmail mailobj, const char* mimetype, char* data, size_t datalen, int mustfree)
 513 {
 514   email_info_attachment_list_add_memory(&mailobj->bodylist, (mimetype ? mimetype : default_mime_type), (mimetype ? mimetype : default_mime_type), data, datalen, mustfree);
 515 }
 516
 517 void quickmail_add_body_custom (quickmail mailobj, const char* mimetype, char* data, quickmail_attachment_open_fn attachment_data_open, quickmail_attachment_read_fn attachment_data_read, quickmail_attachment_close_fn attachment_data_close, quickmail_attachment_free_filedata_fn attachment_data_filedata_free)
 518 {
 519   email_info_attachment_list_add(&mailobj->bodylist, (mimetype ? mimetype : default_mime_type), (mimetype ? mimetype : default_mime_type), data, (attachment_data_open ? attachment_data_open : email_info_attachment_open_dummy), (attachment_data_read ? attachment_data_read : email_info_attachment_read_dummy), attachment_data_close, attachment_data_filedata_free);
 520 }
 521
 522 int quickmail_remove_body (quickmail mailobj, const char* mimetype)
 523 {
 524   return email_info_attachment_list_delete(&mailobj->bodylist, mimetype);
 525 }
 526
 527 void quickmail_list_bodies (quickmail mailobj, quickmail_list_attachment_callback_fn callback, void* callbackdata)
 528 {
 529   struct email_info_attachment_list_struct* p = mailobj->bodylist;
 530   while (p) {
 531     callback(mailobj, p->filename, p->mimetype, p->email_info_attachment_open, p->email_info_attachment_read, p->email_info_attachment_close, callbackdata);
 532     p = p->next;
 533   }
 534 }
 535
 536 void quickmail_add_attachment_file (quickmail mailobj, const char* path, const char* mimetype)
 537 {
 538   email_info_attachment_list_add_file(&mailobj->attachmentlist, path, mimetype);
 539 }
 540
 541 void quickmail_add_attachment_memory (quickmail mailobj, const char* filename, const char* mimetype, char* data, size_t datalen, int mustfree)
 542 {
 543   email_info_attachment_list_add_memory(&mailobj->attachmentlist, filename, mimetype, data, datalen, mustfree);
 544 }
 545
 546 void quickmail_add_attachment_custom (quickmail mailobj, const char* filename, const char* mimetype, char* data, quickmail_attachment_open_fn attachment_data_open, quickmail_attachment_read_fn attachment_data_read, quickmail_attachment_close_fn attachment_data_close, quickmail_attachment_free_filedata_fn attachment_data_filedata_free)
 547 {
 548   email_info_attachment_list_add(&mailobj->attachmentlist, filename, mimetype, data, (attachment_data_open ? attachment_data_open : email_info_attachment_open_dummy), (attachment_data_read ? attachment_data_read : email_info_attachment_read_dummy), attachment_data_close, attachment_data_filedata_free);
 549 }
 550
 551 int quickmail_remove_attachment (quickmail mailobj, const char* filename)
 552 {
 553   return email_info_attachment_list_delete(&mailobj->attachmentlist, filename);
 554 }
 555
 556 void quickmail_list_attachments (quickmail mailobj, quickmail_list_attachment_callback_fn callback, void* callbackdata)
 557 {
 558   struct email_info_attachment_list_struct* p = mailobj->attachmentlist;
 559   while (p) {
 560     callback(mailobj, p->filename, p->mimetype, p->email_info_attachment_open, p->email_info_attachment_read, p->email_info_attachment_close, callbackdata);
 561     p = p->next;
 562   }
 563 }
 564
 565 void quickmail_set_debug_log (quickmail mailobj, FILE* filehandle)
 566 {
 567   mailobj->debuglog = filehandle;
 568 }
 569
 570 void quickmail_fsave (quickmail mailobj, FILE* filehandle)
 571 {
 572   size_t n;
 573   char buf[80];
 574   while ((n = quickmail_get_data(buf, sizeof(buf), 1, mailobj)) > 0) {
 575     for (size_t i = 0; i < n; i++)
 576       fprintf(filehandle, "%c", buf[i]);
 577   }
 578 }
 579
 580 size_t quickmail_get_data (void* ptr, size_t size, size_t nmemb, void* userp)
 581 {
 582   struct email_info_struct* mailobj = (struct email_info_struct*)userp;
 583
 584   //abort if no data is requested
 585   if (size * nmemb == 0)
 586     return 0;
 587
 588   //initialize on first run
 589   if (mailobj->current == MAILPART_INITIALIZE) {
 590     free(mailobj->buf);
 591     mailobj->buf = NULL;
 592     mailobj->buflen = 0;
 593     free(mailobj->mime_boundary_body);
 594     mailobj->mime_boundary_body = NULL;
 595     free(mailobj->mime_boundary_part);
 596     mailobj->mime_boundary_part = NULL;
 597     mailobj->current_attachment = mailobj->bodylist;
 598     mailobj->current++;
 599   }
 600
 601   //process current part of mail if no partial data is pending
 602   while (mailobj->buflen == 0) {
 603     if (mailobj->buflen == 0 && mailobj->current == MAILPART_HEADER) {
 604       char* s;
 605       //generate header part
 606       char** p = &mailobj->buf;
 607       mailobj->buf = NULL;
 608       str_append(p, "User-Agent: libquickmail");
 609       if (mailobj->timestamp != 0) {
 610         char timestamptext[32];
 611         if (strftime(timestamptext, sizeof(timestamptext), "%a, %d %b %Y %H:%M:%S %z", localtime(&mailobj->timestamp))) {\r
 612           str_append(p, "Date: ");
 613           str_append(p, timestamptext);
 614           str_append(p, NEWLINE);
 615         }
 616 #ifdef _WIN32\r
 617         //fallback method for Windows when %z (time zone offset) fails
 618         else if (strftime(timestamptext, sizeof(timestamptext), "%a, %d %b %Y %H:%M:%S", localtime(&mailobj->timestamp))) {\r
 619           TIME_ZONE_INFORMATION tzinfo;\r
 620           if (GetTimeZoneInformation(&tzinfo) != TIME_ZONE_ID_INVALID)\r
 621             sprintf(timestamptext + strlen(timestamptext), " %c%02i%02i", (tzinfo.Bias > 0 ? '-' : '+'), (int)-tzinfo.Bias / 60, (int)-tzinfo.Bias % 60);\r
 622           str_append(p, "Date: ");
 623           str_append(p, timestamptext);
 624           str_append(p, NEWLINE);
 625         }
 626 #endif\r
 627       }
 628       if (mailobj->from && *mailobj->from) {
 629         str_append(p, "From: <");
 630         str_append(p, mailobj->from);
 631         str_append(p, ">" NEWLINE);
 632       }
 633       if ((s = email_info_string_list_concatenate(mailobj->to)) != NULL) {
 634         str_append(p, "To: ");
 635         str_append(p, s);
 636         str_append(p, NEWLINE);
 637         free(s);
 638       }
 639       if ((s = email_info_string_list_concatenate(mailobj->cc)) != NULL) {
 640         str_append(p, "Cc: ");
 641         str_append(p, s);
 642         str_append(p, NEWLINE);
 643         free(s);
 644       }
 645       if (mailobj->subject) {
 646         str_append(p, "Subject: ");
 647         str_append(p, mailobj->subject);
 648         str_append(p, NEWLINE);
 649       }
 650       if (mailobj->header) {
 651         str_append(p, mailobj->header);
 652       }
 653       if (mailobj->attachmentlist) {
 654         str_append(p, "MIME-Version: 1.0" NEWLINE);
 655       }
 656       if (mailobj->attachmentlist) {
 657         mailobj->mime_boundary_part = randomize_zeros(strdup("=PART=SEPARATOR=_0000_0000_0000_0000_0000_0000_="));
 658         str_append(p, "Content-Type: multipart/mixed; boundary=\"");
 659         str_append(p, mailobj->mime_boundary_part);
 660         str_append(p, "\"" NEWLINE NEWLINE "This is a multipart message in MIME format." NEWLINE NEWLINE "--");
 661         str_append(p, mailobj->mime_boundary_part);
 662         str_append(p, NEWLINE);
 663       }
 664       if (mailobj->bodylist && mailobj->bodylist->next) {
 665         mailobj->mime_boundary_body = randomize_zeros(strdup("=BODY=SEPARATOR=_0000_0000_0000_0000_0000_0000_="));
 666         str_append(p, "Content-Type: multipart/alternative; boundary=\"");
 667         str_append(p, mailobj->mime_boundary_body);
 668         str_append(p, NEWLINE);
 669       }
 670       mailobj->buflen = strlen(mailobj->buf);
 671       mailobj->current++;
 672     }
 673     if (mailobj->buflen == 0 && mailobj->current == MAILPART_BODY) {
 674       if (mailobj->current_attachment) {
 675         if (!mailobj->current_attachment->handle) {
 676           //open file with body data
 677           while (mailobj->current_attachment) {
 678             if ((mailobj->current_attachment->handle = mailobj->current_attachment->email_info_attachment_open(mailobj->current_attachment->filedata)) != NULL) {
 679               break;
 680             }
 681             mailobj->current_attachment = mailobj->current_attachment->next;
 682           }
 683           if (!mailobj->current_attachment) {
 684             mailobj->current_attachment = mailobj->attachmentlist;
 685             mailobj->current++;
 686           }
 687           //generate attachment header
 688           if (mailobj->current_attachment && mailobj->current_attachment->handle) {
 689             mailobj->buf = NULL;
 690             if (mailobj->mime_boundary_body) {
 691               mailobj->buf = str_append(&mailobj->buf, NEWLINE "--");
 692               mailobj->buf = str_append(&mailobj->buf, mailobj->mime_boundary_body);
 693               mailobj->buf = str_append(&mailobj->buf, NEWLINE);
 694             }
 695             mailobj->buf = str_append(&mailobj->buf, "Content-Type: ");
 696             mailobj->buf = str_append(&mailobj->buf, (mailobj->bodylist && mailobj->current_attachment->filename ? mailobj->current_attachment->filename : default_mime_type));
 697             mailobj->buf = str_append(&mailobj->buf, NEWLINE "Content-Transfer-Encoding: 8bit" NEWLINE "Content-Disposition: inline" NEWLINE NEWLINE);
 698             mailobj->buflen = strlen(mailobj->buf);
 699           }
 700         }
 701         if (mailobj->buflen == 0 && mailobj->current_attachment && mailobj->current_attachment->handle) {
 702           //read body data
 703         if ((mailobj->buf = (char *) malloc(BODY_BUFFER_SIZE)) == NULL) {
 704             DEBUG_ERROR(ERRMSG_MEMORY_ALLOCATION_ERROR)
 705           }
 706           if (mailobj->buf == NULL || (mailobj->buflen = mailobj->current_attachment->email_info_attachment_read(mailobj->current_attachment->handle, mailobj->buf, BODY_BUFFER_SIZE)) <= 0) {
 707             //end of file
 708             free(mailobj->buf);
 709             mailobj->buflen = 0;
 710             if (mailobj->current_attachment->email_info_attachment_close)
 711               mailobj->current_attachment->email_info_attachment_close(mailobj->current_attachment->handle);
 712             //else
 713             //  free(mailobj->current_attachment->handle);
 714             mailobj->current_attachment->handle = NULL;
 715             mailobj->current_attachment = mailobj->current_attachment->next;
 716           }
 717         }
 718       } else {
 719         mailobj->current_attachment = mailobj->attachmentlist;
 720         mailobj->current++;
 721       }
 722     }
 723     if (mailobj->buflen == 0 && mailobj->current == MAILPART_BODY_DONE) {
 724       mailobj->buf = NULL;
 725       if (mailobj->mime_boundary_body) {
 726         mailobj->buf = str_append(&mailobj->buf, NEWLINE "--");
 727         mailobj->buf = str_append(&mailobj->buf, mailobj->mime_boundary_body);
 728         mailobj->buf = str_append(&mailobj->buf, "--" NEWLINE);
 729         mailobj->buflen = strlen(mailobj->buf);
 730         free(mailobj->mime_boundary_body);
 731         mailobj->mime_boundary_body = NULL;
 732       }
 733       mailobj->current++;
 734     }
 735     if (mailobj->buflen == 0 && mailobj->current == MAILPART_ATTACHMENT) {
 736       if (mailobj->current_attachment) {
 737         if (!mailobj->current_attachment->handle) {
 738           //open file to attach
 739           while (mailobj->current_attachment) {
 740             if ((mailobj->current_attachment->handle = mailobj->current_attachment->email_info_attachment_open(mailobj->current_attachment->filedata)) != NULL) {
 741               break;
 742             }
 743             mailobj->current_attachment = mailobj->current_attachment->next;
 744           }
 745           //generate attachment header
 746           if (mailobj->current_attachment && mailobj->current_attachment->handle) {
 747             mailobj->buf = NULL;
 748             if (mailobj->mime_boundary_part) {
 749               mailobj->buf = str_append(&mailobj->buf, NEWLINE "--");
 750               mailobj->buf = str_append(&mailobj->buf, mailobj->mime_boundary_part);
 751               mailobj->buf = str_append(&mailobj->buf, NEWLINE);
 752             }
 753             mailobj->buf = str_append(&mailobj->buf, "Content-Type: ");
 754             mailobj->buf = str_append(&mailobj->buf, (mailobj->current_attachment->mimetype ? mailobj->current_attachment->mimetype : "application/octet-stream"));
 755             mailobj->buf = str_append(&mailobj->buf, "; Name=\"");
 756             mailobj->buf = str_append(&mailobj->buf, mailobj->current_attachment->filename);
 757             mailobj->buf = str_append(&mailobj->buf, "\"" NEWLINE "Content-Transfer-Encoding: base64" NEWLINE NEWLINE);
 758             mailobj->buflen = strlen(mailobj->buf);
 759           }
 760         } else {
 761           //generate next line of attachment data
 762           size_t n = 0;
 763           int mimelinepos = 0;
 764           unsigned char igroup[3] = {0, 0, 0};
 765           unsigned char ogroup[4];
 766           mailobj->buflen = 0;
 767           if ((mailobj->buf = (char*)malloc(MIME_LINE_WIDTH + NEWLINELENGTH + 1)) == NULL) {
 768             DEBUG_ERROR(ERRMSG_MEMORY_ALLOCATION_ERROR)
 769             n = 0;
 770           } else {
 771             while (mimelinepos < MIME_LINE_WIDTH && (n = mailobj->current_attachment->email_info_attachment_read(mailobj->current_attachment->handle, igroup, 3)) > 0) {
 772               //code data
 773               ogroup[0] = mailobj->dtable[igroup[0] >> 2];
 774               ogroup[1] = mailobj->dtable[((igroup[0] & 3) << 4) | (igroup[1] >> 4)];
 775               ogroup[2] = mailobj->dtable[((igroup[1] & 0xF) << 2) | (igroup[2] >> 6)];
 776               ogroup[3] = mailobj->dtable[igroup[2] & 0x3F];
 777               //padd with "=" characters if less than 3 characters were read
 778               if (n < 3) {
 779                 ogroup[3] = '=';
 780                 if (n < 2)
 781                   ogroup[2] = '=';
 782               }
 783               memcpy(mailobj->buf + mimelinepos, ogroup, 4);
 784               mailobj->buflen += 4;
 785               mimelinepos += 4;
 786             }
 787             if (mimelinepos > 0) {
 788               memcpy(mailobj->buf + mimelinepos, NEWLINE, NEWLINELENGTH);
 789               mailobj->buflen += NEWLINELENGTH;
 790             }
 791           }
 792           if (n <= 0) {
 793             //end of file
 794             if (mailobj->current_attachment->email_info_attachment_close)
 795               mailobj->current_attachment->email_info_attachment_close(mailobj->current_attachment->handle);
 796             else
 797               free(mailobj->current_attachment->handle);
 798             mailobj->current_attachment->handle = NULL;
 799             mailobj->current_attachment = mailobj->current_attachment->next;
 800           }
 801         }
 802       } else {
 803         mailobj->current++;
 804       }
 805     }
 806     if (mailobj->buflen == 0 && mailobj->current == MAILPART_END) {
 807       mailobj->buf = NULL;
 808       mailobj->buflen = 0;
 809       if (mailobj->mime_boundary_part) {
 810         mailobj->buf = str_append(&mailobj->buf, NEWLINE "--");
 811         mailobj->buf = str_append(&mailobj->buf, mailobj->mime_boundary_part);
 812         mailobj->buf = str_append(&mailobj->buf, "--" NEWLINE);
 813         mailobj->buflen = strlen(mailobj->buf);
 814         free(mailobj->mime_boundary_part);
 815         mailobj->mime_boundary_part = NULL;
 816       }
 817       //mailobj->buf = str_append(&mailobj->buf, NEWLINE "." NEWLINE);
 818       //mailobj->buflen = strlen(mailobj->buf);
 819       mailobj->current++;
 820     }
 821     if (mailobj->buflen == 0 && mailobj->current == MAILPART_DONE) {
 822       break;
 823     }
 824   }
 825
 826   //flush pending data if any
 827   if (mailobj->buflen > 0) {
 828           int len = ((size_t) mailobj->buflen > size * nmemb ? size * nmemb : mailobj->buflen);
 829     memcpy(ptr, mailobj->buf, len);
 830     if (len < mailobj->buflen) {
 831       mailobj->buf = (char *) memmove(mailobj->buf, mailobj->buf + len, mailobj->buflen - len);
 832       mailobj->buflen -= len;
 833     } else {
 834       free(mailobj->buf);
 835       mailobj->buf = NULL;
 836       mailobj->buflen = 0;
 837     }
 838     return len;
 839   }
 840
 841   //if (mailobj->current != MAILPART_DONE)
 842   //  ;//this should never be reached
 843   mailobj->current = 0;
 844   return 0;
 845 }
 846
 847 char* add_angle_brackets (const char* data)
 848 {
 849   size_t datalen = strlen(data);
 850   char* result;
 851   if ((result = (char*)malloc(datalen + 3)) == NULL) {
 852     DEBUG_ERROR(ERRMSG_MEMORY_ALLOCATION_ERROR)
 853     return NULL;
 854   }
 855   result[0] = '<';
 856   memcpy(result + 1, data, datalen);
 857   result[datalen + 1] = '>';
 858   result[datalen + 2] = 0;
 859   return result;
 860 }
 861
 862 const char* quickmail_send (quickmail mailobj, const char* smtpserver, unsigned int smtpport, const char* username, const char* password)
 863 {
 864   //libcurl based sending
 865   CURL *curl;
 866   CURLcode result = CURLE_FAILED_INIT;
 867   //curl_global_init(CURL_GLOBAL_ALL);
 868   if ((curl = curl_easy_init()) != NULL) {
 869     struct curl_slist *recipients = NULL;
 870     struct email_info_email_list_struct* listentry;
 871     //set destination URL
 872     char* addr;
 873     size_t len = strlen(smtpserver) + 14;
 874     if ((addr = (char*)malloc(len)) == NULL) {
 875       DEBUG_ERROR(ERRMSG_MEMORY_ALLOCATION_ERROR)
 876       return ERRMSG_MEMORY_ALLOCATION_ERROR;
 877     }
 878     snprintf(addr, len, "smtp://%s:%u", smtpserver, smtpport);
 879     curl_easy_setopt(curl, CURLOPT_URL, addr);
 880     free(addr);
 881     //try Transport Layer Security (TLS), but continue anyway if it fails
 882     curl_easy_setopt(curl, CURLOPT_USE_SSL, (long)CURLUSESSL_TRY);
 883     //don't fail if the TLS/SSL a certificate could not be verified
 884     //alternative: add the issuer certificate (or the host certificate if
 885     //the certificate is self-signed) to the set of certificates that are
 886     //known to libcurl using CURLOPT_CAINFO and/or CURLOPT_CAPATH
 887     curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);
 888     curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);
 889     //set authentication credentials if provided
 890     if (username && *username)
 891       curl_easy_setopt(curl, CURLOPT_USERNAME, username);
 892     if (password)
 893       curl_easy_setopt(curl, CURLOPT_PASSWORD, password);
 894     //set from value for envelope reverse-path
 895     if (mailobj->from && *mailobj->from) {
 896       addr = add_angle_brackets(mailobj->from);
 897       curl_easy_setopt(curl, CURLOPT_MAIL_FROM, addr);
 898       free(addr);
 899     }
 900     //set recipients
 901     listentry = mailobj->to;
 902     while (listentry) {
 903       if (listentry->data && *listentry->data) {
 904         addr = add_angle_brackets(listentry->data);
 905         recipients = curl_slist_append(recipients, addr);
 906         free(addr);
 907       }
 908       listentry = listentry->next;
 909     }
 910     listentry = mailobj->cc;
 911     while (listentry) {
 912       if (listentry->data && *listentry->data) {
 913         addr = add_angle_brackets(listentry->data);
 914         recipients = curl_slist_append(recipients, addr);
 915         free(addr);
 916       }
 917       listentry = listentry->next;
 918     }
 919     listentry = mailobj->bcc;
 920     while (listentry) {
 921       if (listentry->data && *listentry->data) {
 922         addr = add_angle_brackets(listentry->data);
 923         recipients = curl_slist_append(recipients, addr);
 924         free(addr);
 925       }
 926       listentry = listentry->next;
 927     }
 928     curl_easy_setopt(curl, CURLOPT_MAIL_RCPT, recipients);
 929     //set callback function for getting message body
 930     curl_easy_setopt(curl, CURLOPT_READFUNCTION, quickmail_get_data);
 931     curl_easy_setopt(curl, CURLOPT_READDATA, mailobj);
 932     /* Without this curl sends VRFY, which exim errors on
 933        (at least on main.carlh.net)
 934     */
 935     curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);
 936     //enable debugging if requested
 937     if (mailobj->debuglog) {
 938       curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
 939       curl_easy_setopt(curl, CURLOPT_STDERR, mailobj->debuglog);
 940     }
 941     //send the message
 942     result = curl_easy_perform(curl);
 943     //free the list of recipients and clean up
 944     curl_slist_free_all(recipients);
 945     curl_easy_cleanup(curl);
 946   }
 947   return (result == CURLE_OK ? NULL : curl_easy_strerror(result));
 948 }