Cipher Interface SilcCipher Ciphers Cipher-Algorithms SilcCipherMode silc_cipher_register silc_cipher_unregister silc_cipher_register_default silc_cipher_unregister_all silc_cipher_alloc silc_cipher_alloc_full silc_cipher_free silc_cipher_is_supported silc_cipher_get_supported silc_cipher_encrypt silc_cipher_decrypt silc_cipher_set_key silc_cipher_set_iv silc_cipher_get_iv silc_cipher_get_key_len silc_cipher_get_block_len silc_cipher_get_iv_len silc_cipher_get_name silc_cipher_get_alg_name silc_cipher_get_mode

SilcCipherMode

NAME

    typedef enum { ... } SilcCipherMode;

DESCRIPTION

Cipher modes. Notes about cipher modes and implementation:

SILC_CIPHER_MODE_CBC

      The Cipher-block Chaining mode.  The plaintext length must be
      multiple by the cipher block size.  If it isn't the plaintext must
      be padded.

SILC_CIPHER_MODE_CTR

      The Counter mode.  The CTR mode does not require the plaintext length
      to be multiple by the cipher block size.  If the last plaintext block
      is shorter the remaining bits of the key stream are used next time
      silc_cipher_encrypt is called.  If silc_cipher_set_iv is called it
      will reset the counter for a new block (discarding any remaining
      bits from previous key stream).  The CTR mode expects MSB first
      ordered counter.  Note also, the counter is incremented when
      silc_cipher_encrypt is called for the first time, before encrypting.

SILC_CIPHER_MODE_CFB

      The Cipher Feedback mode.  The CFB mode does not require the plaintext
      length to be multiple by the cipher block size.  If the last plaintext
      block is shorter the remaining bits of the stream are used next time
      silc_cipher_encrypt is called.  If silc_cipher_set_iv is called it
      will reset the feedback for a new block (discarding any remaining
      bits from previous stream).

SILC_CIPHER_MODE_OFB

      The Output Feedback mode.

SILC_CIPHER_MODE_ECB

      The Electronic Codebook mode.  This mode does not provide sufficient
      security and should not be used alone.

Each mode using and IV (initialization vector) modifies the IV of the cipher when silc_cipher_encrypt or silc_cipher_decrypt is called. The IV may be set/reset by calling silc_cipher_set_iv and the current IV can be retrieved by calling silc_cipher_get_iv.

SOURCE

typedef enum {
  SILC_CIPHER_MODE_ECB = 1,     /* ECB mode */
  SILC_CIPHER_MODE_CBC = 2,     /* CBC mode */
  SILC_CIPHER_MODE_CTR = 3,     /* CTR mode */
  SILC_CIPHER_MODE_CFB = 4,     /* CFB mode */
  SILC_CIPHER_MODE_OFB = 5,     /* OFB mode */
} SilcCipherMode;