PHP. Руководство по PHP. 2005
mcrypt_enc_get_iv_size
mcrypt_enc_get_iv_size
Description
int mcrypt_enc_get_iv_size (resource td)This function returns the size of the iv of the algorithm specified by the encryption descriptor in bytes. If it returns '0' then the IV is ignored in the algorithm. An IV is used in cbc, cfb and ofb modes, and in some algorithms in stream mode.
mcrypt_enc_get_block_size
mcrypt_enc_get_key_size
