ossl_session_cipher
struct ossl_session_cipher cipher;
ossl_aes_gcm(struct ossl_session_cipher *s, struct cryptop *crp,
ossl_aes_cbc(struct ossl_session_cipher *s, struct cryptop *crp,
ossl_chacha20(struct ossl_session_cipher *s, struct cryptop *crp,
struct ossl_session_cipher;
typedef int (ossl_cipher_process_t)(struct ossl_session_cipher*, struct cryptop*,