tom_crypto.c

   1 #ifdef HAVE_CONFIG_H
   2 # include "config.h"
   3 #endif
   4 #include <tomcrypt.h>
   5
   6 #include "crypto_if.h"
   7
   8 static const char *tom_init(void)
   9 {
  10         /* nothing to initialize */
  11         return "tomcrypt";
  12 }
  13
  14 static unsigned long tom_encrypt(void *key, int keylen, void *iv,
  15                         void *pt, void *ct, int tlen)
  16 {
  17         symmetric_CBC cbc;
  18         int index, err;
  19
  20         if ((index = register_cipher(&aes_desc)) == -1)
  21                 return CRYPT_INVALID_CIPHER;
  22         if ((err = cbc_start(index, iv, key, keylen, 0, &cbc)) != CRYPT_OK)
  23                 return err;
  24         err= cbc_encrypt(pt, ct, tlen, &cbc);
  25         (void)cbc_done(&cbc);
  26         return err;
  27 }
  28
  29 static unsigned long tom_decrypt(void *key, int keylen, void *iv,
  30                         void *ct, void *pt, int tlen)
  31 {
  32         symmetric_CBC cbc;
  33         int index, err;
  34
  35         if ((index = register_cipher(&aes_desc)) == -1)
  36                 return CRYPT_INVALID_CIPHER;
  37         if ((err = cbc_start(index, iv, key, keylen, 0, &cbc)) != CRYPT_OK)
  38                 return err;
  39         err= cbc_decrypt(ct, pt, tlen, &cbc);
  40         (void)cbc_done(&cbc);
  41         return err;
  42 }
  43
  44 static unsigned long tom_hash(void *pt, int tlen, void *tag, int *taglen)
  45 {
  46         int index, rc;
  47         unsigned long ltaglen = *taglen;
  48
  49         if ((index = register_hash(&sha1_desc)) == -1)
  50                 return CRYPT_INVALID_HASH;
  51         rc = hash_memory(index, pt, tlen, tag, &ltaglen);
  52         *taglen = ltaglen;
  53         return rc;
  54 }
  55
  56 static unsigned long tom_hmac(void *key, int keylen,
  57                         void *pt, int tlen, void *tag, int *taglen)
  58 {
  59         int index, rc;
  60         unsigned long ltaglen = *taglen;
  61
  62         if ((index = register_hash(&sha1_desc)) == -1)
  63                 return CRYPT_INVALID_HASH;
  64         rc = hmac_memory(index, key, keylen, pt, tlen, tag, &ltaglen);
  65         *taglen = ltaglen;
  66         return rc;
  67 }
  68
  69 static const char *tom_errstr(unsigned long err)
  70 {
  71         return error_to_string((int)err);
  72 }
  73
  74 struct crypto_interface tom_crypto_if = {
  75         .init           = tom_init,
  76         .encrypt        = tom_encrypt,
  77         .decrypt        = tom_decrypt,
  78         .hash           = tom_hash,
  79         .hmac           = tom_hmac,
  80         .errstr         = tom_errstr,
  81 };