git.zerfleddert.de Git - proxmark3-svn/blob - client/emv/emv_pki_priv.c

   1 /*
   2  * libopenemv - a library to work with EMV family of smart cards
   3  * Copyright (C) 2015 Dmitry Eremin-Solenikov
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2.1 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  */
  15
  16 #ifdef HAVE_CONFIG_H
  17 #include <config.h>
  18 #endif
  19
  20 #include "emv_pki_priv.h"
  21 #include "crypto.h"
  22
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <stdarg.h>
  26
  27 struct emv_pk *emv_pki_make_ca(const struct crypto_pk *cp,
  28                 const unsigned char *rid, unsigned char index,
  29                 unsigned int expire, enum crypto_algo_hash hash_algo)
  30 {
  31         size_t modlen, explen;
  32         unsigned char *mod, *exp;
  33
  34         if (!rid)
  35                 return NULL;
  36
  37         mod = crypto_pk_get_parameter(cp, 0, &modlen);
  38         exp = crypto_pk_get_parameter(cp, 1, &explen);
  39
  40         if (!mod || !modlen || !exp || !explen) {
  41                 free(mod);
  42                 free(exp);
  43
  44                 return NULL;
  45         }
  46
  47         struct emv_pk *pk = emv_pk_new(modlen, explen);
  48         memcpy(pk->rid, rid, 5);
  49         pk->index = index;
  50         pk->expire = expire;
  51         pk->pk_algo = crypto_pk_get_algo(cp);
  52         pk->hash_algo = hash_algo;
  53         memcpy(pk->modulus, mod, modlen);
  54         memcpy(pk->exp, exp, explen);
  55
  56         free(mod);
  57         free(exp);
  58
  59         struct crypto_hash *ch = crypto_hash_open(pk->hash_algo);
  60         if (!ch) {
  61                 emv_pk_free(pk);
  62                 return false;
  63         }
  64
  65         crypto_hash_write(ch, pk->rid, sizeof(pk->rid));
  66         crypto_hash_write(ch, &pk->index, 1);
  67         crypto_hash_write(ch, pk->modulus, pk->mlen);
  68         crypto_hash_write(ch, pk->exp, pk->elen);
  69
  70         unsigned char *h = crypto_hash_read(ch);
  71         if (!h) {
  72                 crypto_hash_close(ch);
  73                 emv_pk_free(pk);
  74
  75                 return NULL;
  76         }
  77
  78         memcpy(pk->hash, h, crypto_hash_get_size(ch));
  79         crypto_hash_close(ch);
  80
  81         return pk;
  82 }
  83
  84 static struct tlvdb *emv_pki_sign_message(const struct crypto_pk *cp,
  85                 tlv_tag_t cert_tag, tlv_tag_t rem_tag,
  86                 const unsigned char *msg, size_t msg_len,
  87                 ... /* A list of tlv pointers, end with NULL */
  88                 )
  89 {
  90         size_t tmp_len = (crypto_pk_get_nbits(cp) + 7) / 8;
  91         unsigned char *tmp = malloc(tmp_len);
  92         if (!tmp)
  93                 return NULL;
  94
  95         // XXX
  96         struct crypto_hash *ch = crypto_hash_open(HASH_SHA_1);
  97         if (!ch) {
  98                 free(tmp);
  99
 100                 return NULL;
 101         }
 102
 103         tmp[0] = 0x6a;
 104         tmp[tmp_len - 1] = 0xbc;
 105
 106         const unsigned char *rem;
 107         size_t rem_len;
 108         size_t hash_len = crypto_hash_get_size(ch);
 109         size_t part_len = tmp_len - 2 - hash_len;
 110         if (part_len < msg_len) {
 111                 memcpy(tmp + 1, msg, part_len);
 112                 rem = msg + part_len;
 113                 rem_len = msg_len - part_len;
 114         } else {
 115                 memcpy(tmp + 1, msg, msg_len);
 116                 memset(tmp + 1 + msg_len, 0xbb, part_len - msg_len);
 117                 rem = NULL;
 118                 rem_len = 0;
 119         }
 120         crypto_hash_write(ch, tmp + 1, part_len);
 121         crypto_hash_write(ch, rem, rem_len);
 122
 123         va_list vl;
 124         va_start(vl, msg_len);
 125         while (true) {
 126                 const struct tlv *add_tlv = va_arg(vl, const struct tlv *);
 127                 if (!add_tlv)
 128                         break;
 129
 130                 crypto_hash_write(ch, add_tlv->value, add_tlv->len);
 131         }
 132         va_end(vl);
 133
 134         unsigned char *h = crypto_hash_read(ch);
 135         if (!h) {
 136                 crypto_hash_close(ch);
 137                 free(tmp);
 138
 139                 return NULL;
 140         }
 141
 142         memcpy(tmp + 1 + part_len, h, hash_len);
 143         crypto_hash_close(ch);
 144
 145         size_t cert_len;
 146         unsigned char *cert = crypto_pk_decrypt(cp, tmp, tmp_len, &cert_len);
 147         free(tmp);
 148
 149         if (!cert)
 150                 return NULL;
 151
 152         struct tlvdb *db = tlvdb_fixed(cert_tag, cert_len, cert);
 153         free(cert);
 154         if (!db)
 155                 return NULL;
 156
 157         if (rem) {
 158                 struct tlvdb *rdb = tlvdb_fixed(rem_tag, rem_len, rem);
 159                 if (!rdb) {
 160                         tlvdb_free(db);
 161
 162                         return NULL;
 163                 }
 164                 tlvdb_add(db, rdb);
 165         }
 166
 167         return db;
 168 }
 169
 170 static struct tlvdb *emv_pki_sign_key(const struct crypto_pk *cp,
 171                 struct emv_pk *ipk,
 172                 unsigned char msgtype,
 173                 size_t pan_len,
 174                 tlv_tag_t cert_tag,
 175                 tlv_tag_t exp_tag,
 176                 tlv_tag_t rem_tag,
 177                 const struct tlv *add_tlv
 178                 )
 179 {
 180         unsigned pos = 0;
 181         unsigned char *msg = malloc(1 + pan_len + 2 + 3 + 1 + 1 + 1 + 1 + ipk->mlen);
 182
 183         if (!msg)
 184                 return NULL;
 185
 186         msg[pos++] = msgtype;
 187         memcpy(msg + pos, ipk->pan, pan_len); pos += pan_len;
 188         msg[pos++] = (ipk->expire >> 8) & 0xff;
 189         msg[pos++] = (ipk->expire >> 16) & 0xff;
 190         memcpy(msg + pos, ipk->serial, 3); pos += 3;
 191         msg[pos++] = ipk->hash_algo;
 192         msg[pos++] = ipk->pk_algo;
 193         msg[pos++] = ipk->mlen;
 194         msg[pos++] = ipk->elen;
 195         memcpy(msg + pos, ipk->modulus, ipk->mlen);
 196         pos += ipk->mlen;
 197
 198         struct tlvdb *exp_db = tlvdb_fixed(exp_tag, ipk->elen, ipk->exp);
 199         if (!exp_db) {
 200                 free(msg);
 201
 202                 return NULL;
 203         }
 204
 205         struct tlvdb *db = emv_pki_sign_message(cp,
 206                         cert_tag, rem_tag,
 207                         msg, pos,
 208                         tlvdb_get(exp_db, exp_tag, NULL),
 209                         add_tlv,
 210                         NULL);
 211         free(msg);
 212         if (!db)
 213                 return NULL;
 214
 215         tlvdb_add(db, exp_db);
 216
 217         return db;
 218 }
 219
 220 struct tlvdb *emv_pki_sign_issuer_cert(const struct crypto_pk *cp, struct emv_pk *issuer_pk)
 221 {
 222         return emv_pki_sign_key(cp, issuer_pk, 2, 4, 0x90, 0x9f32, 0x92, NULL);
 223 }
 224
 225 struct tlvdb *emv_pki_sign_icc_cert(const struct crypto_pk *cp, struct emv_pk *icc_pk, const struct tlv *sda_tlv)
 226 {
 227         return emv_pki_sign_key(cp, icc_pk, 4, 10, 0x9f46, 0x9f47, 0x9f48, sda_tlv);
 228 }
 229
 230 struct tlvdb *emv_pki_sign_icc_pe_cert(const struct crypto_pk *cp, struct emv_pk *icc_pe_pk)
 231 {
 232         return emv_pki_sign_key(cp, icc_pe_pk, 4, 10, 0x9f2d, 0x9f2e, 0x9f2f, NULL);
 233 }
 234
 235 struct tlvdb *emv_pki_sign_dac(const struct crypto_pk *cp, const struct tlv *dac_tlv, const struct tlv *sda_tlv)
 236 {
 237         unsigned pos = 0;
 238         unsigned char *msg = malloc(1+1+dac_tlv->len);
 239
 240         if (!msg)
 241                 return NULL;
 242
 243         msg[pos++] = 3;
 244         msg[pos++] = HASH_SHA_1;
 245         memcpy(msg+pos, dac_tlv->value, dac_tlv->len);
 246         pos += dac_tlv->len;
 247
 248         struct tlvdb *db = emv_pki_sign_message(cp,
 249                         0x93, 0,
 250                         msg, pos,
 251                         sda_tlv,
 252                         NULL);
 253
 254         free(msg);
 255
 256         return db;
 257 }
 258
 259 struct tlvdb *emv_pki_sign_idn(const struct crypto_pk *cp, const struct tlv *idn_tlv, const struct tlv *dyn_tlv)
 260 {
 261         unsigned pos = 0;
 262         unsigned char *msg = malloc(1+1+1+1+idn_tlv->len);
 263
 264         if (!msg)
 265                 return NULL;
 266
 267         msg[pos++] = 5;
 268         msg[pos++] = HASH_SHA_1;
 269         msg[pos++] = idn_tlv->len + 1;
 270         msg[pos++] = idn_tlv->len;
 271         memcpy(msg+pos, idn_tlv->value, idn_tlv->len);
 272         pos += idn_tlv->len;
 273
 274         struct tlvdb *db = emv_pki_sign_message(cp,
 275                         0x9f4b, 0,
 276                         msg, pos,
 277                         dyn_tlv,
 278                         NULL);
 279
 280         free(msg);
 281
 282         return db;
 283 }