prf_hash_ctx
struct prf_hash_ctx *prfctx = prf->prfctx;
void prf_hash_init(struct prf_hash_ctx *);
void prf_hash_update(struct prf_hash_ctx *, unsigned char *, unsigned int);
void prf_hash_final(unsigned char *, struct prf_hash_ctx *);
prf_hash_init(struct prf_hash_ctx *ctx)
prf_hash_update(struct prf_hash_ctx *ctx, unsigned char *data,
prf_hash_final(unsigned char *digest, struct prf_hash_ctx *ctx)
struct prf_hash_ctx *prfctx;