ike_alg.h

This a good VPN source

#ifndef _IKE_ALG_H
#define _IKE_ALG_H

/* forward reference */
struct connection;

struct ike_alg {
  u_int16_t algo_type;	
  u_int16_t algo_id;	
  struct ike_alg *algo_next;
};

struct encrypt_desc {
  struct ike_alg common;
  size_t enc_ctxsize;
  size_t enc_blocksize;
  unsigned keydeflen;
  unsigned keymaxlen;
  unsigned keyminlen;
  void (*do_crypt)(u_int8_t *dat, size_t datasize, u_int8_t *key, size_t key_size, u_int8_t *iv, bool enc);
};

struct hash_desc {
  struct ike_alg common;
  size_t hash_ctx_size;
  size_t hash_digest_len;
  void (*hash_init)(void *ctx);
  void (*hash_update)(void *ctx, const u_int8_t *in, size_t datasize);
  void (*hash_final)(u_int8_t *out, void *ctx);
};

struct db_context * ike_alg_db_new(struct alg_info_ike *ai, lset_t policy);
void ike_alg_show_status(void);
void ike_alg_show_connection(struct connection *c, const char *instance);

#define IKE_EALG_FOR_EACH(a) \
	for(a=ike_alg_base[IKE_ALG_ENCRYPT];a;a=a->algo_next)
#define IKE_HALG_FOR_EACH(a) \
	for(a=ike_alg_base[IKE_ALG_HASH];a;a=a->algo_next)
bool ike_alg_enc_present(int ealg);
bool ike_alg_hash_present(int halg);
bool ike_alg_enc_ok(int ealg, unsigned key_len, struct alg_info_ike *alg_info_ike, const char **);
bool ike_alg_ok_final(int ealg, unsigned key_len, int aalg, int group, struct alg_info_ike *alg_info_ike);

int ike_alg_init(void);

/*	
 *	This could be just OAKLEY_XXXXXX_ALGORITHM, but it's
 *	here with other name as a way to assure that the
 *	algorithm hook type is supported (detected at compile time)
 */
#define IKE_ALG_ENCRYPT	0
#define IKE_ALG_HASH	1
#define IKE_ALG_MAX	1
extern struct ike_alg *ike_alg_base[IKE_ALG_MAX+1];
int ike_alg_add(struct ike_alg *);
int ike_alg_register_enc(struct encrypt_desc *e);
int ike_alg_register_hash(struct hash_desc *a);
struct ike_alg *ike_alg_find(unsigned algo_type, unsigned algo_id, unsigned keysize);
static __inline__ struct hash_desc *ike_alg_get_hasher(int alg)
{
	return (struct hash_desc *) ike_alg_find(IKE_ALG_HASH, alg, 0);
}
static __inline__ struct encrypt_desc *ike_alg_get_encrypter(int alg)
{
	return (struct encrypt_desc *) ike_alg_find(IKE_ALG_ENCRYPT, alg, 0);
}
const struct oakley_group_desc * ike_alg_pfsgroup(struct connection *c, lset_t policy);

extern struct db_sa *oakley_alg_makedb(struct alg_info_ike *ai
				       , struct db_sa *basic
				       , int maxtrans);

extern struct db_sa *kernel_alg_makedb(struct alg_info_esp *ai);
#endif /* _IKE_ALG_H */