contrib/opie/libopie/verify.c

   1 /* verify.c: The opieverify() library function.
   2
   3 %%% copyright-cmetz-96
   4 This software is Copyright 1996-2001 by Craig Metz, All Rights Reserved.
   5 The Inner Net License Version 3 applies to this software.
   6 You should have received a copy of the license with this software. If
   7 you didn't get a copy, you may request one from <license@inner.net>.
   8
   9         History:
  10
  11         Modified by cmetz for OPIE 2.4. Use struct opie_otpkey for keys.
  12                 Check that seed and sequence number are valid.
  13         Modified by cmetz for OPIE 2.32. Renamed _opieparsechallenge() to
  14                 __opieparsechallenge() and handle new argument. Fixed init
  15                 response parsing bug.
  16         Modified by cmetz for OPIE 2.31. Renamed "init" to "init-hex".
  17         Modified by cmetz for OPIE 2.31. Renamed "init" and "RESPONSE_INIT"
  18                 to "init-hex" and "RESPONSE_INIT_HEX". Removed active attack
  19                 protection support.
  20         Created by cmetz for OPIE 2.3 using the old verify.c as a guide.
  21 */
  22
  23 #include "opie_cfg.h"
  24 #ifdef HAVE_STRING_H
  25 #include <string.h>
  26 #endif /* HAVE_STRING_H */
  27 #include <ctype.h>
  28 #include "opie.h"
  29
  30 #define RESPONSE_STANDARD  0
  31 #define RESPONSE_WORD      1
  32 #define RESPONSE_HEX       2
  33 #define RESPONSE_INIT_HEX  3
  34 #define RESPONSE_INIT_WORD 4
  35 #define RESPONSE_UNKNOWN   5
  36
  37 struct _rtrans {
  38   int type;
  39   char *name;
  40 };
  41
  42 static struct _rtrans rtrans[] = {
  43   { RESPONSE_WORD, "word" },
  44   { RESPONSE_HEX, "hex" },
  45   { RESPONSE_INIT_HEX, "init-hex" },
  46   { RESPONSE_INIT_WORD, "init-word" },
  47   { RESPONSE_STANDARD, "" },
  48   { RESPONSE_UNKNOWN, NULL }
  49 };
  50
  51 static int changed FUNCTION((opie), struct opie *opie)
  52 {
  53   struct opie opie2;
  54
  55   memset(&opie2, 0, sizeof(struct opie));
  56   opie2.opie_principal = opie->opie_principal;
  57   if (__opiereadrec(&opie2))
  58     return 1;
  59
  60   if ((opie2.opie_n != opie->opie_n) || strcmp(opie2.opie_val, opie->opie_val) || strcmp(opie2.opie_seed, opie->opie_seed))
  61     return 1;
  62
  63   memset(&opie2, 0, sizeof(struct opie));
  64   return 0;
  65 }
  66
  67 int opieverify FUNCTION((opie, response), struct opie *opie AND char *response)
  68 {
  69   int i, rval = -1;
  70   char *c;
  71   struct opie_otpkey key, fkey, lastkey;
  72
  73   if (!opie || !response)
  74     goto verret;
  75
  76   if (!opie->opie_principal)
  77 #if DEBUG
  78     abort();
  79 #else /* DEBUG */
  80     goto verret;
  81 #endif /* DEBUG */
  82
  83   if (!opieatob8(&lastkey, opie->opie_val))
  84     goto verret;
  85
  86   for (c = opie->opie_seed; *c; c++)
  87     if (!isalnum(*c))
  88       goto verret;
  89
  90   if (opie->opie_n <= 0)
  91     goto verret;
  92
  93   if ((c = strchr(response, ':')) != NULL) {
  94     *(c++) = 0;
  95     {
  96       struct _rtrans *r;
  97       for (r = rtrans; r->name && strcmp(r->name, response); r++);
  98       i = r->type;
  99     }
 100   } else
 101     i = RESPONSE_STANDARD;
 102
 103   switch(i) {
 104   case RESPONSE_STANDARD:
 105     i = 1;
 106
 107     if (opieetob(&key, response) == 1) {
 108       memcpy(&fkey, &key, sizeof(struct opie_otpkey));
 109       opiehash(&fkey, MDX);
 110       i = memcmp(&fkey, &lastkey, sizeof(struct opie_otpkey));
 111     }
 112     if (i && opieatob8(&key, response)) {
 113       memcpy(&fkey, &key, sizeof(struct opie_otpkey));
 114       opiehash(&fkey, MDX);
 115       i = memcmp(&fkey, &lastkey, sizeof(struct opie_otpkey));
 116     }
 117     break;
 118   case RESPONSE_WORD:
 119     i = 1;
 120
 121     if (opieetob(&key, c) == 1) {
 122       memcpy(&fkey, &key, sizeof(struct opie_otpkey));
 123       opiehash(&fkey, MDX);
 124       i = memcmp(&fkey, &lastkey, sizeof(struct opie_otpkey));
 125     }
 126     break;
 127   case RESPONSE_HEX:
 128     i = 1;
 129
 130     if (opieatob8(&key, c)) {
 131       memcpy(&fkey, &key, sizeof(struct opie_otpkey));
 132       opiehash(&fkey, MDX);
 133       i = memcmp(&fkey, &lastkey, sizeof(struct opie_otpkey));
 134     }
 135     break;
 136   case RESPONSE_INIT_HEX:
 137   case RESPONSE_INIT_WORD:
 138     {
 139       char *c2;
 140
 141       if (!(c2 = strchr(c, ':')))
 142         goto verret;
 143
 144       *(c2++) = 0;
 145
 146       if (i == RESPONSE_INIT_HEX) {
 147         if (!opieatob8(&key, c))
 148           goto verret;
 149       } else {
 150         if (opieetob(&key, c) != 1)
 151           goto verret;
 152       }
 153
 154       memcpy(&fkey, &key, sizeof(struct opie_otpkey));
 155       opiehash(&fkey, MDX);
 156
 157       if (memcmp(&fkey, &lastkey, sizeof(struct opie_otpkey)))
 158         goto verret;
 159
 160       if (changed(opie))
 161         goto verret;
 162
 163       opie->opie_n--;
 164
 165       if (!opiebtoa8(opie->opie_val, &key))
 166         goto verret;
 167
 168       if (__opiewriterec(opie))
 169         goto verret;
 170
 171       if (!(c2 = strchr(c = c2, ':')))
 172         goto verret;
 173
 174       *(c2++) = 0;
 175
 176       {
 177         int j, k;
 178
 179         if (__opieparsechallenge(c, &j, &(opie->opie_n), &(opie->opie_seed), &k) || (j != MDX) || k)
 180           goto verret;
 181       }
 182
 183       if (i == RESPONSE_INIT_HEX) {
 184         if (!opieatob8(&key, c2))
 185           goto verret;
 186       } else {
 187         if (opieetob(&key, c2) != 1)
 188           goto verret;
 189       }
 190     }
 191     goto verwrt;
 192   case RESPONSE_UNKNOWN:
 193     rval = 1;
 194     goto verret;
 195   default:
 196     rval = -1;
 197     goto verret;
 198   }
 199
 200   if (i) {
 201     rval = 1;
 202     goto verret;
 203   }
 204
 205   if (changed(opie))
 206     goto verret;
 207
 208   opie->opie_n--;
 209
 210 verwrt:
 211   if (!opiebtoa8(opie->opie_val, &key))
 212     goto verret;
 213   rval = __opiewriterec(opie);
 214
 215 verret:
 216   opieunlock();
 217   memset(opie, 0, sizeof(struct opie));
 218   return rval;
 219 }