Added cipher_info_from_values() to cipher layer (Search by ID+keylen+mode)
diff --git a/include/polarssl/cipher.h b/include/polarssl/cipher.h
index 7628d6c..b7c03cb 100644
--- a/include/polarssl/cipher.h
+++ b/include/polarssl/cipher.h
@@ -286,6 +286,22 @@
const cipher_info_t *cipher_info_from_type( const cipher_type_t cipher_type );
/**
+ * \brief Returns the cipher information structure associated
+ * with the given cipher id, key size and mode.
+ *
+ * \param cipher_id Id of the cipher to search for
+ * (e.g. POLARSSL_CIPHER_ID_AES)
+ * \param key_length Length of the key in bits
+ * \param mode Cipher mode (e.g. POLARSSL_MODE_CBC)
+ *
+ * \return the cipher information structure associated with the
+ * given cipher_type, or NULL if not found.
+ */
+const cipher_info_t *cipher_info_from_values( const cipher_id_t cipher_id,
+ int key_length,
+ const cipher_mode_t mode );
+
+/**
* \brief Initialises and fills the cipher context structure with
* the appropriate values.
*
diff --git a/library/cipher.c b/library/cipher.c
index 8e59e62..b23969c 100644
--- a/library/cipher.c
+++ b/library/cipher.c
@@ -379,6 +379,185 @@
return NULL;
}
+const cipher_info_t *cipher_info_from_values( const cipher_id_t cipher_id,
+ int key_length,
+ const cipher_mode_t mode )
+{
+#if defined(POLARSSL_AES_C)
+ if( cipher_id == POLARSSL_CIPHER_ID_AES )
+ {
+ if( mode == POLARSSL_MODE_ECB )
+ {
+ if( key_length == 128 )
+ return &aes_128_ecb_info;
+ if( key_length == 192 )
+ return &aes_192_ecb_info;
+ if( key_length == 256 )
+ return &aes_256_ecb_info;
+ }
+
+ if( mode == POLARSSL_MODE_CBC )
+ {
+ if( key_length == 128 )
+ return &aes_128_cbc_info;
+ if( key_length == 192 )
+ return &aes_192_cbc_info;
+ if( key_length == 256 )
+ return &aes_256_cbc_info;
+ }
+
+#if defined(POLARSSL_CIPHER_MODE_CFB)
+ if( mode == POLARSSL_MODE_CFB )
+ {
+ if( key_length == 128 )
+ return &aes_128_cfb128_info;
+ if( key_length == 192 )
+ return &aes_192_cfb128_info;
+ if( key_length == 256 )
+ return &aes_256_cfb128_info;
+ }
+#endif /* defined(POLARSSL_CIPHER_MODE_CFB) */
+
+#if defined(POLARSSL_CIPHER_MODE_CTR)
+ if( mode == POLARSSL_MODE_CTR )
+ {
+ if( key_length == 128 )
+ return &aes_128_ctr_info;
+ if( key_length == 192 )
+ return &aes_192_ctr_info;
+ if( key_length == 256 )
+ return &aes_256_ctr_info;
+ }
+#endif /* defined(POLARSSL_CIPHER_MODE_CTR) */
+
+#if defined(POLARSSL_GCM_C)
+ if( mode == POLARSSL_MODE_GCM )
+ {
+ if( key_length == 128 )
+ return &aes_128_gcm_info;
+ if( key_length == 192 )
+ return &aes_192_gcm_info;
+ if( key_length == 256 )
+ return &aes_256_gcm_info;
+ }
+#endif /* defined(POLARSSL_GCM_C) */
+ }
+#endif
+
+#if defined(POLARSSL_CAMELLIA_C)
+ if( cipher_id == POLARSSL_CIPHER_ID_CAMELLIA )
+ {
+ if( mode == POLARSSL_MODE_ECB )
+ {
+ if( key_length == 128 )
+ return &camellia_128_ecb_info;
+ if( key_length == 192 )
+ return &camellia_192_ecb_info;
+ if( key_length == 256 )
+ return &camellia_256_ecb_info;
+ }
+
+ if( mode == POLARSSL_MODE_CBC )
+ {
+ if( key_length == 128 )
+ return &camellia_128_cbc_info;
+ if( key_length == 192 )
+ return &camellia_192_cbc_info;
+ if( key_length == 256 )
+ return &camellia_256_cbc_info;
+ }
+
+#if defined(POLARSSL_CIPHER_MODE_CFB)
+ if( mode == POLARSSL_MODE_CFB )
+ {
+ if( key_length == 128 )
+ return &camellia_128_cfb128_info;
+ if( key_length == 192 )
+ return &camellia_192_cfb128_info;
+ if( key_length == 256 )
+ return &camellia_256_cfb128_info;
+ }
+#endif /* defined(POLARSSL_CIPHER_MODE_CFB) */
+
+#if defined(POLARSSL_CIPHER_MODE_CTR)
+ if( mode == POLARSSL_MODE_CTR )
+ {
+ if( key_length == 128 )
+ return &camellia_128_ctr_info;
+ if( key_length == 192 )
+ return &camellia_192_ctr_info;
+ if( key_length == 256 )
+ return &camellia_256_ctr_info;
+ }
+#endif /* defined(POLARSSL_CIPHER_MODE_CTR) */
+ }
+#endif
+
+#if defined(POLARSSL_DES_C)
+ if( cipher_id == POLARSSL_CIPHER_ID_DES )
+ {
+ if( mode == POLARSSL_MODE_ECB )
+ return &des_ecb_info;
+
+ if( mode == POLARSSL_MODE_CBC )
+ return &des_cbc_info;
+ }
+
+ if( cipher_id == POLARSSL_CIPHER_ID_3DES )
+ {
+ if( mode == POLARSSL_MODE_ECB )
+ {
+ if( key_length == 128 )
+ return &des_ede_ecb_info;
+ if( key_length == 192 )
+ return &des_ede3_ecb_info;
+ }
+
+ if( mode == POLARSSL_MODE_CBC )
+ {
+ if( key_length == 128 )
+ return &des_ede_cbc_info;
+ if( key_length == 192 )
+ return &des_ede3_cbc_info;
+ }
+ }
+#endif
+
+#if defined(POLARSSL_ARC4_C)
+ if( cipher_id == POLARSSL_CIPHER_ID_ARC4 )
+ if( mode == POLARSSL_MODE_STREAM )
+ return &arc4_128_info;
+#endif
+
+#if defined(POLARSSL_BLOWFISH_C)
+ if( cipher_id == POLARSSL_CIPHER_ID_BLOWFISH )
+ {
+ if( mode == POLARSSL_MODE_ECB )
+ return &blowfish_ecb_info;
+
+ if( mode == POLARSSL_MODE_CBC )
+ return &blowfish_cbc_info;
+
+#if defined(POLARSSL_CIPHER_MODE_CFB)
+ if( mode == POLARSSL_MODE_CFB )
+ return &blowfish_cfb64_info;
+#endif /* defined(POLARSSL_CIPHER_MODE_CFB) */
+
+#if defined(POLARSSL_CIPHER_MODE_CTR)
+ if( mode == POLARSSL_MODE_CTR )
+ return &blowfish_ctr_info;
+#endif /* defined(POLARSSL_CIPHER_MODE_CTR) */
+ }
+#endif
+
+#if defined(POLARSSL_CIPHER_NULL_CIPHER)
+ if( cipher_id == POLARSSL_CIPHER_ID_NULL )
+ return &null_cipher_info;
+#endif /* defined(POLARSSL_CIPHER_NULL_CIPHER) */
+
+ return NULL;
+}
+
int cipher_init_ctx( cipher_context_t *ctx, const cipher_info_t *cipher_info )
{
if( NULL == cipher_info || NULL == ctx )
