src/crypto_openssl.c

   1
   2 #include <assert.h>
   3 #include <locale.h>
   4 #include <openssl/err.h>
   5 #include <openssl/md5.h>
   6 #include <openssl/sha.h>
   7
   8 #include "isds_priv.h"
   9 #include "utils.h"
  10
  11
  12 #ifndef SHA1_DIGEST_LENGTH
  13 #  define SHA1_DIGEST_LENGTH 20
  14 #endif /* !SHA1_DIGEST_LENGTH */
  15
  16
  17 /* Initialise all cryptographic libraries which libisds depends on.
  18  * @return IE_SUCCESS if everything went all-right. */
  19 _hidden isds_error _isds_init_crypto_openssl(void)
  20 {
  21     ERR_load_crypto_strings();
  22
  23     return IE_SUCCESS;
  24 }
  25
  26 /* Computes hash from @input with @length and store it into @hash.
  27  * The hash algorithm is defined inside @hash.
  28  * @input is input block to hash
  29  * @length is @input block length in bytes
  30  * @hash input algorithm, output hash value and hash length; hash value will be
  31  * reallocated, it's always valid pointer or NULL (before and after call) */
  32 _hidden isds_error _isds_compute_hash_openssl(const void *input, const size_t length,
  33         struct isds_hash *hash)
  34 {
  35     void *hash_buf = NULL;
  36     size_t hash_len = 0;
  37     unsigned char * (*hash_func)(const unsigned char *, size_t n,
  38         unsigned char *) = NULL;
  39
  40     if (((0 != length) && (NULL == input)) || (NULL == hash)) {
  41         return IE_INVAL;
  42     }
  43
  44     isds_log(ILF_SEC, ILL_DEBUG,
  45             _("Data hash requested, length=%zu, content:\n%*s\n"
  46                 "End of data to hash\n"), length, length, input);
  47
  48     /* Select algorithm */
  49     switch (hash->algorithm) {
  50     case HASH_ALGORITHM_MD5:
  51         hash_len = MD5_DIGEST_LENGTH;
  52         hash_func = MD5;
  53         break;
  54     case HASH_ALGORITHM_SHA_1:
  55         hash_len = SHA1_DIGEST_LENGTH;
  56         hash_func = SHA1;
  57         break;
  58     case HASH_ALGORITHM_SHA_224:
  59         hash_len = SHA224_DIGEST_LENGTH;
  60         hash_func = SHA224;
  61         break;
  62     case HASH_ALGORITHM_SHA_256:
  63         hash_len = SHA256_DIGEST_LENGTH;
  64         hash_func = SHA256;
  65         break;
  66     case HASH_ALGORITHM_SHA_384:
  67         hash_len = SHA384_DIGEST_LENGTH;
  68         hash_func = SHA384;
  69         break;
  70     case HASH_ALGORITHM_SHA_512:
  71         hash_len = SHA512_DIGEST_LENGTH;
  72         hash_func = SHA512;
  73         break;
  74     default:
  75         return IE_NOTSUP;
  76     }
  77
  78     assert(0 != hash_len);
  79
  80     /* Get known the hash length and allocate buffer for hash value */
  81     hash->length = hash_len;
  82     hash_buf = realloc(hash->value, hash->length);
  83     if (NULL == hash_buf) {
  84         return IE_NOMEM;
  85     }
  86     hash->value = hash_buf;
  87
  88     assert(NULL != hash->value);
  89     assert(NULL != hash_func);
  90
  91     /* Compute the hash */
  92     hash_func(input, length, hash->value);
  93
  94     return IE_SUCCESS;
  95 }
  96
  97 /* Free CMS data buffer allocated inside _isds_extract_cms_data().
  98  * This is necessary because GPGME.
  99  * @buffer is pointer to memory to free */
 100 _hidden void _isds_cms_data_free_openssl(void *buffer)
 101 {
 102 }
 103
 104 /* Extract data from CMS (successor of PKCS#7)
 105  * @context is session context
 106  * @cms is input block with CMS structure
 107  * @cms_length is @cms block length in bytes
 108  * @data are automatically reallocated bit stream with data found in @cms
 109  * You must free them with _isds_cms_data_free().
 110  * @data_length is length of @data in bytes */
 111 _hidden isds_error _isds_extract_cms_data_openssl(struct isds_ctx *context,
 112         const void *cms, const size_t cms_length,
 113         void **data, size_t *data_length)
 114 {
 115     assert(NULL != context);
 116
 117     if ((NULL == cms) || (0 == cms_length) ||
 118         (NULL == data) || (NULL == data_length)) {
 119         return IE_INVAL;
 120     }
 121
 122     /* TODO */
 123
 124     return IE_ERROR;
 125 }