ssl.c

   1 /*
   2  * S-nail - a mail user agent derived from Berkeley Mail.
   3  *
   4  * Copyright (c) 2000-2004 Gunnar Ritter, Freiburg i. Br., Germany.
   5  * Copyright (c) 2012 Steffen "Daode" Nurpmeso.
   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 #include "config.h"
  41
  42 #ifndef USE_SSL
  43 typedef int avoid_empty_file_compiler_warning;
  44 #else
  45
  46 #include "rcv.h"
  47 #include "extern.h"
  48
  49 void
  50 ssl_set_vrfy_level(const char *uhp)
  51 {
  52         char *cp;
  53         char *vrvar;
  54
  55         ssl_vrfy_level = VRFY_ASK;
  56         vrvar = ac_alloc(strlen(uhp) + 12);
  57         strcpy(vrvar, "ssl-verify-");
  58         strcpy(&vrvar[11], uhp);
  59         if ((cp = value(vrvar)) == NULL)
  60                 cp = value("ssl-verify");
  61         ac_free(vrvar);
  62         if (cp != NULL) {
  63                 if (strcmp(cp, "strict") == 0)
  64                         ssl_vrfy_level = VRFY_STRICT;
  65                 else if (strcmp(cp, "ask") == 0)
  66                         ssl_vrfy_level = VRFY_ASK;
  67                 else if (strcmp(cp, "warn") == 0)
  68                         ssl_vrfy_level = VRFY_WARN;
  69                 else if (strcmp(cp, "ignore") == 0)
  70                         ssl_vrfy_level = VRFY_IGNORE;
  71                 else
  72                         fprintf(stderr, tr(265,
  73                                 "invalid value of ssl-verify: %s\n"), cp);
  74         }
  75 }
  76
  77 enum okay
  78 ssl_vrfy_decide(void)
  79 {
  80         enum okay ok = STOP;
  81
  82         switch (ssl_vrfy_level) {
  83         case VRFY_STRICT:
  84                 ok = STOP;
  85                 break;
  86         case VRFY_ASK:
  87                 {
  88                         char *line = NULL;
  89                         size_t linesize = 0;
  90
  91                         fprintf(stderr, catgets(catd, CATSET, 264,
  92                                         "Continue (y/n)? "));
  93                         if (readline(stdin, &line, &linesize) > 0 &&
  94                                         *line == 'y')
  95                                 ok = OKAY;
  96                         else
  97                                 ok = STOP;
  98                         if (line)
  99                                 free(line);
 100                 }
 101                 break;
 102         case VRFY_WARN:
 103         case VRFY_IGNORE:
 104                 ok = OKAY;
 105         }
 106         return ok;
 107 }
 108
 109 char *
 110 ssl_method_string(const char *uhp)
 111 {
 112         char *cp, *mtvar;
 113
 114         mtvar = ac_alloc(strlen(uhp) + 12);
 115         strcpy(mtvar, "ssl-method-");
 116         strcpy(&mtvar[11], uhp);
 117         if ((cp = value(mtvar)) == NULL)
 118                 cp = value("ssl-method");
 119         ac_free(mtvar);
 120         return cp;
 121 }
 122
 123 enum okay
 124 smime_split(FILE *ip, FILE **hp, FILE **bp, long xcount, int keep)
 125 {
 126         char    *buf, *hn, *bn;
 127         char    *savedfields = NULL;
 128         size_t  bufsize, buflen, count, savedsize = 0;
 129         int     c;
 130
 131         if ((*hp = Ftemp(&hn, "Rh", "w+", 0600, 1)) == NULL ||
 132                         (*bp = Ftemp(&bn, "Rb", "w+", 0600, 1)) == NULL) {
 133                 perror("tempfile");
 134                 return STOP;
 135         }
 136         rm(hn);
 137         rm(bn);
 138         Ftfree(&hn);
 139         Ftfree(&bn);
 140         buf = smalloc(bufsize = LINESIZE);
 141         savedfields = smalloc(savedsize = 1);
 142         *savedfields = '\0';
 143         if (xcount < 0)
 144                 count = fsize(ip);
 145         else
 146                 count = xcount;
 147         while (fgetline(&buf, &bufsize, &count, &buflen, ip, 0) != NULL &&
 148                         *buf != '\n') {
 149                 if (ascncasecmp(buf, "content-", 8) == 0) {
 150                         if (keep)
 151                                 fputs("X-Encoded-", *hp);
 152                         for (;;) {
 153                                 savedsize += buflen;
 154                                 savedfields = srealloc(savedfields, savedsize);
 155                                 strcat(savedfields, buf);
 156                                 if (keep)
 157                                         fwrite(buf, sizeof *buf, buflen, *hp);
 158                                 c = getc(ip);
 159                                 ungetc(c, ip);
 160                                 if (!blankchar(c))
 161                                         break;
 162                                 fgetline(&buf, &bufsize, &count, &buflen,
 163                                                 ip, 0);
 164                         }
 165                         continue;
 166                 }
 167                 fwrite(buf, sizeof *buf, buflen, *hp);
 168         }
 169         fflush(*hp);
 170         rewind(*hp);
 171         fputs(savedfields, *bp);
 172         putc('\n', *bp);
 173         while (fgetline(&buf, &bufsize, &count, &buflen, ip, 0) != NULL)
 174                 fwrite(buf, sizeof *buf, buflen, *bp);
 175         fflush(*bp);
 176         rewind(*bp);
 177         free(buf);
 178         return OKAY;
 179 }
 180
 181 FILE *
 182 smime_sign_assemble(FILE *hp, FILE *bp, FILE *sp)
 183 {
 184         char    *boundary, *cp;
 185         FILE    *op;
 186         int     c, lastc = EOF;
 187
 188         if ((op = Ftemp(&cp, "Rs", "w+", 0600, 1)) == NULL) {
 189                 perror("tempfile");
 190                 return NULL;
 191         }
 192         rm(cp);
 193         Ftfree(&cp);
 194         boundary = makeboundary();
 195         while ((c = getc(hp)) != EOF) {
 196                 if (c == '\n' && lastc == '\n')
 197                         break;
 198                 putc(c, op);
 199                 lastc = c;
 200         }
 201         fprintf(op, "Content-Type: multipart/signed;\n"
 202                 " protocol=\"application/x-pkcs7-signature\"; micalg=sha1;\n"
 203                 " boundary=\"%s\"\n\n", boundary);
 204         fprintf(op, "This is an S/MIME signed message.\n\n--%s\n",
 205                         boundary);
 206         while ((c = getc(bp)) != EOF)
 207                 putc(c, op);
 208         fprintf(op, "\n--%s\n", boundary);
 209         fputs("Content-Type: application/x-pkcs7-signature; "
 210                         "name=\"smime.p7s\"\n"
 211                 "Content-Transfer-Encoding: base64\n"
 212                 "Content-Disposition: attachment; filename=\"smime.p7s\"\n\n",
 213                 op);
 214         while ((c = getc(sp)) != EOF) {
 215                 if (c == '-') {
 216                         while ((c = getc(sp)) != EOF && c != '\n');
 217                         continue;
 218                 }
 219                 putc(c, op);
 220         }
 221         fprintf(op, "\n--%s--\n", boundary);
 222         Fclose(hp);
 223         Fclose(bp);
 224         Fclose(sp);
 225         fflush(op);
 226         if (ferror(op)) {
 227                 perror("signed output data");
 228                 Fclose(op);
 229                 return NULL;
 230         }
 231         rewind(op);
 232         return op;
 233 }
 234
 235 FILE *
 236 smime_encrypt_assemble(FILE *hp, FILE *yp)
 237 {
 238         char    *cp;
 239         FILE    *op;
 240         int     c, lastc = EOF;
 241
 242         if ((op = Ftemp(&cp, "Rs", "w+", 0600, 1)) == NULL) {
 243                 perror("tempfile");
 244                 return NULL;
 245         }
 246         rm(cp);
 247         Ftfree(&cp);
 248         while ((c = getc(hp)) != EOF) {
 249                 if (c == '\n' && lastc == '\n')
 250                         break;
 251                 putc(c, op);
 252                 lastc = c;
 253         }
 254         fprintf(op, "Content-Type: application/x-pkcs7-mime; "
 255                         "name=\"smime.p7m\"\n"
 256                 "Content-Transfer-Encoding: base64\n"
 257                 "Content-Disposition: attachment; "
 258                         "filename=\"smime.p7m\"\n\n");
 259         while ((c = getc(yp)) != EOF) {
 260                 if (c == '-') {
 261                         while ((c = getc(yp)) != EOF && c != '\n');
 262                         continue;
 263                 }
 264                 putc(c, op);
 265         }
 266         Fclose(hp);
 267         Fclose(yp);
 268         fflush(op);
 269         if (ferror(op)) {
 270                 perror("encrypted output data");
 271                 Fclose(op);
 272                 return NULL;
 273         }
 274         rewind(op);
 275         return op;
 276 }
 277
 278 struct message *
 279 smime_decrypt_assemble(struct message *m, FILE *hp, FILE *bp)
 280 {
 281         int     binary = 0, lastnl = 0;
 282         char    *buf = NULL, *cp;
 283         size_t  bufsize = 0, buflen, count;
 284         long    lines = 0, octets = 0;
 285         struct message  *x;
 286         off_t   offset;
 287
 288         x = salloc(sizeof *x);
 289         *x = *m;
 290         fflush(mb.mb_otf);
 291         fseek(mb.mb_otf, 0L, SEEK_END);
 292         offset = ftell(mb.mb_otf);
 293         count = fsize(hp);
 294         while (fgetline(&buf, &bufsize, &count, &buflen, hp, 0) != NULL) {
 295                 if (buf[0] == '\n')
 296                         break;
 297                 if ((cp = thisfield(buf, "content-transfer-encoding")) != NULL)
 298                         if (ascncasecmp(cp, "binary", 7) == 0)
 299                                 binary = 1;
 300                 fwrite(buf, sizeof *buf, buflen, mb.mb_otf);
 301                 octets += buflen;
 302                 lines++;
 303         }
 304         octets += mkdate(mb.mb_otf, "X-Decoding-Date");
 305         lines++;
 306         count = fsize(bp);
 307         while (fgetline(&buf, &bufsize, &count, &buflen, bp, 0) != NULL) {
 308                 lines++;
 309                 if (!binary && buf[buflen-1] == '\n' && buf[buflen-2] == '\r')
 310                         buf[--buflen-1] = '\n';
 311                 fwrite(buf, sizeof *buf, buflen, mb.mb_otf);
 312                 octets += buflen;
 313                 if (buf[0] == '\n')
 314                         lastnl++;
 315                 else if (buf[buflen-1] == '\n')
 316                         lastnl = 1;
 317                 else
 318                         lastnl = 0;
 319         }
 320         while (!binary && lastnl < 2) {
 321                 putc('\n', mb.mb_otf);
 322                 lines++;
 323                 octets++;
 324                 lastnl++;
 325         }
 326         Fclose(hp);
 327         Fclose(bp);
 328         free(buf);
 329         fflush(mb.mb_otf);
 330         if (ferror(mb.mb_otf)) {
 331                 perror("decrypted output data");
 332                 return NULL;
 333         }
 334         x->m_size = x->m_xsize = octets;
 335         x->m_lines = x->m_xlines = lines;
 336         x->m_block = mailx_blockof(offset);
 337         x->m_offset = mailx_offsetof(offset);
 338         return x;
 339 }
 340
 341 int
 342 ccertsave(void *v)
 343 {
 344         int     *ip;
 345         int     f, *msgvec;
 346         char    *file = NULL, *str = v;
 347         int     val = 0;
 348         FILE    *fp;
 349
 350         msgvec = salloc((msgCount + 2) * sizeof *msgvec);
 351         if ((file = laststring(str, &f, 1)) == NULL) {
 352                 fprintf(stderr, "No file to save certificate given.\n");
 353                 return 1;
 354         }
 355         if (!f) {
 356                 *msgvec = first(0, MMNORM);
 357                 if (*msgvec == 0) {
 358                         if (inhook)
 359                                 return 0;
 360                         fprintf(stderr,
 361                                 "No messages to get certificates from.\n");
 362                         return 1;
 363                 }
 364                 msgvec[1] = 0;
 365         } else if (getmsglist(str, msgvec, 0) < 0)
 366                 return 1;
 367         if (*msgvec == 0) {
 368                 if (inhook)
 369                         return 0;
 370                 fprintf(stderr, "No applicable messages.\n");
 371                 return 1;
 372         }
 373         if ((fp = Fopen(file, "a")) == NULL) {
 374                 perror(file);
 375                 return 1;
 376         }
 377         for (ip = msgvec; *ip && ip-msgvec < msgCount; ip++)
 378                 if (smime_certsave(&message[*ip-1], *ip, fp) != OKAY)
 379                         val = 1;
 380         Fclose(fp);
 381         if (val == 0)
 382                 printf("Certificate(s) saved.\n");
 383         return val;
 384 }
 385 enum okay
 386 rfc2595_hostname_match(const char *host, const char *pattern)
 387 {
 388         if (pattern[0] == '*' && pattern[1] == '.') {
 389                 pattern++;
 390                 while (*host && *host != '.')
 391                         host++;
 392         }
 393         return asccasecmp(host, pattern) == 0 ? OKAY : STOP;
 394 }
 395 #endif  /* USE_SSL */