ssl.c

   1 /*@ S-nail - a mail user agent derived from Berkeley Mail.
   2  *@ Generic SSL / SMIME commands.
   3  *
   4  * Copyright (c) 2000-2004 Gunnar Ritter, Freiburg i. Br., Germany.
   5  * Copyright (c) 2012 - 2014 Steffen "Daode" Nurpmeso <sdaoden@users.sf.net>.
   6  */
   7 /*
   8  * Copyright (c) 2002
   9  *      Gunnar Ritter.  All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. All advertising materials mentioning features or use of this software
  20  *    must display the following acknowledgement:
  21  *      This product includes software developed by Gunnar Ritter
  22  *      and his contributors.
  23  * 4. Neither the name of Gunnar Ritter nor the names of his contributors
  24  *    may be used to endorse or promote products derived from this software
  25  *    without specific prior written permission.
  26  *
  27  * THIS SOFTWARE IS PROVIDED BY GUNNAR RITTER AND CONTRIBUTORS ``AS IS'' AND
  28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  30  * ARE DISCLAIMED.  IN NO EVENT SHALL GUNNAR RITTER OR CONTRIBUTORS BE LIABLE
  31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  37  * SUCH DAMAGE.
  38  */
  39
  40 #ifndef HAVE_AMALGAMATION
  41 # include "nail.h"
  42 #endif
  43
  44 EMPTY_FILE(ssl)
  45 #ifdef HAVE_SSL
  46 FL void
  47 ssl_set_vrfy_level(const char *uhp)
  48 {
  49         size_t l;
  50         char *cp, *vrvar;
  51
  52         ssl_vrfy_level = VRFY_ASK;
  53         l = strlen(uhp);
  54         vrvar = ac_alloc(l + 12);
  55         memcpy(vrvar, "ssl-verify-", 11);
  56         memcpy(vrvar + 11, uhp, l + 1);
  57
  58         if ((cp = vok_vlook(vrvar)) == NULL)
  59                 cp = ok_vlook(ssl_verify);
  60         ac_free(vrvar);
  61         if (cp != NULL) {
  62                 if (strcmp(cp, "strict") == 0)
  63                         ssl_vrfy_level = VRFY_STRICT;
  64                 else if (strcmp(cp, "ask") == 0)
  65                         ssl_vrfy_level = VRFY_ASK;
  66                 else if (strcmp(cp, "warn") == 0)
  67                         ssl_vrfy_level = VRFY_WARN;
  68                 else if (strcmp(cp, "ignore") == 0)
  69                         ssl_vrfy_level = VRFY_IGNORE;
  70                 else
  71                         fprintf(stderr, tr(265,
  72                                 "invalid value of ssl-verify: %s\n"), cp);
  73         }
  74 }
  75
  76 FL enum okay
  77 ssl_vrfy_decide(void)
  78 {
  79         enum okay ok = STOP;
  80
  81         switch (ssl_vrfy_level) {
  82         case VRFY_STRICT:
  83                 ok = STOP;
  84                 break;
  85         case VRFY_ASK:
  86                 {
  87                         char *line = NULL;
  88                         size_t linesize = 0;
  89
  90                         fprintf(stderr, tr(264, "Continue (y/n)? "));
  91                         if (readline_restart(stdin, &line, &linesize, 0) > 0 &&
  92                                         *line == 'y')
  93                                 ok = OKAY;
  94                         else
  95                                 ok = STOP;
  96                         if (line)
  97                                 free(line);
  98                 }
  99                 break;
 100         case VRFY_WARN:
 101         case VRFY_IGNORE:
 102                 ok = OKAY;
 103         }
 104         return ok;
 105 }
 106
 107 FL char *
 108 ssl_method_string(const char *uhp)
 109 {
 110         size_t l;
 111         char *cp, *mtvar;
 112
 113         l = strlen(uhp);
 114         mtvar = ac_alloc(l + 12);
 115         memcpy(mtvar, "ssl-method-", 11);
 116         memcpy(mtvar + 11, uhp, l + 1);
 117         if ((cp = vok_vlook(mtvar)) == NULL)
 118                 cp = ok_vlook(ssl_method);
 119         ac_free(mtvar);
 120         return cp;
 121 }
 122
 123 FL enum okay
 124 smime_split(FILE *ip, FILE **hp, FILE **bp, long xcount, int keep)
 125 {
 126         /* TODO like i said quite often now, the entire SSL stuff really needs
 127          * TODO a review ASAP; also in respect to correct resource release, and
 128          * TODO especially in case of errors; S-nail is a program that REALLY
 129          * TODO may run for a week or longer!!! */
 130         char    *buf, *hn, *bn;
 131         char    *savedfields = NULL;
 132         size_t  bufsize, buflen, cnt, savedsize = 0;
 133         int     c;
 134
 135         if ((*hp = Ftemp(&hn, "Rh", "w+", 0600, 1)) == NULL)
 136                 goto jetmp;
 137         rm(hn);
 138         Ftfree(&hn);
 139         if ((*bp = Ftemp(&bn, "Rb", "w+", 0600, 1)) == NULL) {
 140 jetmp:
 141                 perror("tempfile");
 142                 return STOP;
 143         }
 144         rm(bn);
 145         Ftfree(&bn);
 146
 147         buf = smalloc(bufsize = LINESIZE);
 148         savedfields = smalloc(savedsize = 1);
 149         *savedfields = '\0';
 150         if (xcount < 0)
 151                 cnt = fsize(ip);
 152         else
 153                 cnt = xcount;
 154
 155         while (fgetline(&buf, &bufsize, &cnt, &buflen, ip, 0) != NULL &&
 156                         *buf != '\n') {
 157                 if (ascncasecmp(buf, "content-", 8) == 0) {
 158                         if (keep)
 159                                 fputs("X-Encoded-", *hp);
 160                         for (;;) {
 161                                 savedsize += buflen;
 162                                 savedfields = srealloc(savedfields, savedsize);
 163                                 memcpy(savedfields + strlen(savedfields),
 164                                         buf, strlen(buf));
 165                                 if (keep)
 166                                         fwrite(buf, sizeof *buf, buflen, *hp);
 167                                 c = getc(ip);
 168                                 ungetc(c, ip);
 169                                 if (!blankchar(c))
 170                                         break;
 171                                 fgetline(&buf, &bufsize, &cnt, &buflen,
 172                                                 ip, 0);
 173                         }
 174                         continue;
 175                 }
 176                 fwrite(buf, sizeof *buf, buflen, *hp);
 177         }
 178         fflush(*hp);
 179         rewind(*hp);
 180
 181         fputs(savedfields, *bp);
 182         putc('\n', *bp);
 183         while (fgetline(&buf, &bufsize, &cnt, &buflen, ip, 0) != NULL)
 184                 fwrite(buf, sizeof *buf, buflen, *bp);
 185         fflush(*bp);
 186         rewind(*bp);
 187
 188         free(savedfields);
 189         free(buf);
 190         return OKAY;
 191 }
 192
 193 FL FILE *
 194 smime_sign_assemble(FILE *hp, FILE *bp, FILE *sp)
 195 {
 196         char    *boundary, *cp;
 197         FILE    *op;
 198         int     c, lastc = EOF;
 199
 200         if ((op = Ftemp(&cp, "Rs", "w+", 0600, 1)) == NULL) {
 201                 perror("tempfile");
 202                 return NULL;
 203         }
 204         rm(cp);
 205         Ftfree(&cp);
 206         boundary = mime_create_boundary();
 207         while ((c = getc(hp)) != EOF) {
 208                 if (c == '\n' && lastc == '\n')
 209                         break;
 210                 putc(c, op);
 211                 lastc = c;
 212         }
 213         fprintf(op, "Content-Type: multipart/signed;\n"
 214                 " protocol=\"application/x-pkcs7-signature\"; micalg=sha1;\n"
 215                 " boundary=\"%s\"\n\n", boundary);
 216         fprintf(op, "This is an S/MIME signed message.\n\n--%s\n",
 217                         boundary);
 218         while ((c = getc(bp)) != EOF)
 219                 putc(c, op);
 220         fprintf(op, "\n--%s\n", boundary);
 221         fputs("Content-Type: application/x-pkcs7-signature; "
 222                         "name=\"smime.p7s\"\n"
 223                 "Content-Transfer-Encoding: base64\n"
 224                 "Content-Disposition: attachment; filename=\"smime.p7s\"\n\n",
 225                 op);
 226         while ((c = getc(sp)) != EOF) {
 227                 if (c == '-') {
 228                         while ((c = getc(sp)) != EOF && c != '\n');
 229                         continue;
 230                 }
 231                 putc(c, op);
 232         }
 233         fprintf(op, "\n--%s--\n", boundary);
 234         Fclose(hp);
 235         Fclose(bp);
 236         Fclose(sp);
 237         fflush(op);
 238         if (ferror(op)) {
 239                 perror("signed output data");
 240                 Fclose(op);
 241                 return NULL;
 242         }
 243         rewind(op);
 244         return op;
 245 }
 246
 247 FL FILE *
 248 smime_encrypt_assemble(FILE *hp, FILE *yp)
 249 {
 250         char    *cp;
 251         FILE    *op;
 252         int     c, lastc = EOF;
 253
 254         if ((op = Ftemp(&cp, "Rs", "w+", 0600, 1)) == NULL) {
 255                 perror("tempfile");
 256                 return NULL;
 257         }
 258         rm(cp);
 259         Ftfree(&cp);
 260         while ((c = getc(hp)) != EOF) {
 261                 if (c == '\n' && lastc == '\n')
 262                         break;
 263                 putc(c, op);
 264                 lastc = c;
 265         }
 266         fprintf(op, "Content-Type: application/x-pkcs7-mime; "
 267                         "name=\"smime.p7m\"\n"
 268                 "Content-Transfer-Encoding: base64\n"
 269                 "Content-Disposition: attachment; "
 270                         "filename=\"smime.p7m\"\n\n");
 271         while ((c = getc(yp)) != EOF) {
 272                 if (c == '-') {
 273                         while ((c = getc(yp)) != EOF && c != '\n');
 274                         continue;
 275                 }
 276                 putc(c, op);
 277         }
 278         Fclose(hp);
 279         Fclose(yp);
 280         fflush(op);
 281         if (ferror(op)) {
 282                 perror("encrypted output data");
 283                 Fclose(op);
 284                 return NULL;
 285         }
 286         rewind(op);
 287         return op;
 288 }
 289
 290 FL struct message *
 291 smime_decrypt_assemble(struct message *m, FILE *hp, FILE *bp)
 292 {
 293         ui32_t lastnl = 0;
 294         int     binary = 0;
 295         char    *buf = NULL;
 296         size_t  bufsize = 0, buflen, cnt;
 297         long    lines = 0, octets = 0;
 298         struct message  *x;
 299         off_t   offset;
 300
 301         x = salloc(sizeof *x);
 302         *x = *m;
 303         fflush(mb.mb_otf);
 304         fseek(mb.mb_otf, 0L, SEEK_END);
 305         offset = ftell(mb.mb_otf);
 306         cnt = fsize(hp);
 307         while (fgetline(&buf, &bufsize, &cnt, &buflen, hp, 0) != NULL) {
 308                 char const *cp;
 309                 if (buf[0] == '\n')
 310                         break;
 311                 if ((cp = thisfield(buf, "content-transfer-encoding")) != NULL)
 312                         if (ascncasecmp(cp, "binary", 7) == 0)
 313                                 binary = 1;
 314                 fwrite(buf, sizeof *buf, buflen, mb.mb_otf);
 315                 octets += buflen;
 316                 lines++;
 317         }
 318         octets += mkdate(mb.mb_otf, "X-Decoding-Date");
 319         lines++;
 320         cnt = fsize(bp);
 321         while (fgetline(&buf, &bufsize, &cnt, &buflen, bp, 0) != NULL) {
 322                 lines++;
 323                 if (!binary && buf[buflen-1] == '\n' && buf[buflen-2] == '\r')
 324                         buf[--buflen-1] = '\n';
 325                 fwrite(buf, sizeof *buf, buflen, mb.mb_otf);
 326                 octets += buflen;
 327                 if (buf[0] == '\n')
 328                         lastnl++;
 329                 else if (buf[buflen-1] == '\n')
 330                         lastnl = 1;
 331                 else
 332                         lastnl = 0;
 333         }
 334         while (!binary && lastnl < 2) {
 335                 putc('\n', mb.mb_otf);
 336                 lines++;
 337                 octets++;
 338                 lastnl++;
 339         }
 340         Fclose(hp);
 341         Fclose(bp);
 342         free(buf);
 343         fflush(mb.mb_otf);
 344         if (ferror(mb.mb_otf)) {
 345                 perror("decrypted output data");
 346                 return NULL;
 347         }
 348         x->m_size = x->m_xsize = octets;
 349         x->m_lines = x->m_xlines = lines;
 350         x->m_block = mailx_blockof(offset);
 351         x->m_offset = mailx_offsetof(offset);
 352         return x;
 353 }
 354
 355 FL int
 356 ccertsave(void *v)
 357 {
 358         int     *ip;
 359         int     *msgvec;
 360         char    *file = NULL, *str = v;
 361         int     val = 0;
 362         FILE    *fp;
 363         bool_t  f;
 364
 365         msgvec = salloc((msgCount + 2) * sizeof *msgvec);
 366         if ((file = laststring(str, &f, 1)) == NULL) {
 367                 fprintf(stderr, "No file to save certificate given.\n");
 368                 return 1;
 369         }
 370         if (!f) {
 371                 *msgvec = first(0, MMNORM);
 372                 if (*msgvec == 0) {
 373                         if (inhook)
 374                                 return 0;
 375                         fprintf(stderr,
 376                                 "No messages to get certificates from.\n");
 377                         return 1;
 378                 }
 379                 msgvec[1] = 0;
 380         } else if (getmsglist(str, msgvec, 0) < 0)
 381                 return 1;
 382         if (*msgvec == 0) {
 383                 if (inhook)
 384                         return 0;
 385                 fprintf(stderr, "No applicable messages.\n");
 386                 return 1;
 387         }
 388         if ((fp = Fopen(file, "a")) == NULL) {
 389                 perror(file);
 390                 return 1;
 391         }
 392         for (ip = msgvec; *ip && ip-msgvec < msgCount; ip++)
 393                 if (smime_certsave(&message[*ip-1], *ip, fp) != OKAY)
 394                         val = 1;
 395         Fclose(fp);
 396         if (val == 0)
 397                 printf("Certificate(s) saved.\n");
 398         return val;
 399 }
 400
 401 FL enum okay
 402 rfc2595_hostname_match(const char *host, const char *pattern)
 403 {
 404         if (pattern[0] == '*' && pattern[1] == '.') {
 405                 pattern++;
 406                 while (*host && *host != '.')
 407                         host++;
 408         }
 409         return asccasecmp(host, pattern) == 0 ? OKAY : STOP;
 410 }
 411 #endif /* HAVE_SSL */