/* SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause */
/*
 * SunRPC GSS Kerberos 5 mechanism internal definitions
 *
 * Copyright (c) 2022 Oracle and/or its affiliates.
 */

#ifndef _NET_SUNRPC_AUTH_GSS_KRB5_INTERNAL_H
#define _NET_SUNRPC_AUTH_GSS_KRB5_INTERNAL_H

#include <crypto/krb5.h>

struct krb5_ctx;

/* krb5_ctx flags definitions */
#define KRB5_CTX_FLAG_INITIATOR         0x00000001
#define KRB5_CTX_FLAG_ACCEPTOR_SUBKEY   0x00000004

struct krb5_ctx {
        int                     initiate; /* 1 = initiating, 0 = accepting */
        u32                     enctype;
        u32                     flags;
        const struct krb5_enctype *krb5e; /* crypto/krb5 enctype */
        struct crypto_aead      *initiator_enc_aead;
        struct crypto_aead      *acceptor_enc_aead;
        struct crypto_shash     *initiator_sign_shash;
        struct crypto_shash     *acceptor_sign_shash;
        u8                      Ksess[GSS_KRB5_MAX_KEYLEN]; /* session key */
        atomic64_t              seq_send64;
        time64_t                endtime;
        struct xdr_netobj       mech_used;
};

/*
 * GSS Kerberos 5 mechanism Per-Message calls.
 */

u32 gss_krb5_get_mic_v2(struct krb5_ctx *ctx, struct xdr_buf *text,
                        struct xdr_netobj *token);

u32 gss_krb5_verify_mic_v2(struct krb5_ctx *ctx, struct xdr_buf *message_buffer,
                           struct xdr_netobj *read_token);

u32 gss_krb5_wrap_v2(struct krb5_ctx *kctx, int offset,
                     struct xdr_buf *buf, struct page **pages);

u32 gss_krb5_unwrap_v2(struct krb5_ctx *kctx, int offset, int len,
                       struct xdr_buf *buf, unsigned int *slack,
                       unsigned int *align);

/*
 * Implementation internal functions
 */

int xdr_extend_head(struct xdr_buf *buf, unsigned int base,
                    unsigned int shiftlen);

u32 gss_krb5_errno_to_status(int err);

int gss_krb5_mic_build_sg(const struct xdr_buf *body,
                          void *cksum, unsigned int cksum_len,
                          void *hdr,
                          struct scatterlist *sg_head,
                          struct scatterlist **sg_overflow);

u32 gss_krb5_aead_encrypt(struct krb5_ctx *kctx, u32 offset,
                          struct xdr_buf *buf, struct page **pages);
u32 gss_krb5_aead_decrypt(struct krb5_ctx *kctx, u32 offset, u32 len,
                          struct xdr_buf *buf, u32 *headskip, u32 *tailskip);


#endif /* _NET_SUNRPC_AUTH_GSS_KRB5_INTERNAL_H */