/* SPDX-License-Identifier: GPL-2.0 */

/*
 * Modifications for Lustre
 *
 * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
 *
 * Author: Eric Mei <ericm@clusterfs.com>
 */

/*
 * linux/include/linux/sunrpc/gss_api.h
 *
 * Somewhat simplified version of the gss api.
 *
 * Dug Song <dugsong@monkey.org>
 * Andy Adamson <andros@umich.edu>
 * Bruce Fields <bfields@umich.edu>
 * Copyright (c) 2000 The Regents of the University of Michigan
 */

#ifndef __PTLRPC_GSS_GSS_API_H_
#define __PTLRPC_GSS_GSS_API_H_

#include <uapi/linux/lustre/lgss.h>

struct gss_api_mech;

typedef int (*digest_hash)(
	struct ahash_request *req, rawobj_t *hdr,
	int msgcnt, rawobj_t *msgs,
	int iovcnt, struct bio_vec *iovs);

/* The mechanism-independent gss-api context: */
struct gss_ctx {
	struct gss_api_mech *mech_type;
	void *internal_ctx_id;
	digest_hash hash_func;
};

#define GSS_C_NO_BUFFER         ((rawobj_t) 0)
#define GSS_C_NO_CONTEXT        ((struct gss_ctx *) 0)
#define GSS_C_NULL_OID          ((rawobj_t) 0)

/*
 * gss-api prototypes; note that these are somewhat simplified versions of
 * the prototypes specified in RFC 2744.
 */
__u32 lgss_import_sec_context(
                rawobj_t                *input_token,
                struct gss_api_mech     *mech,
                struct gss_ctx         **ctx);
__u32 lgss_copy_reverse_context(
                struct gss_ctx          *ctx,
                struct gss_ctx         **ctx_new);
__u32 lgss_inquire_context(
                struct gss_ctx          *ctx,
		time64_t *endtime);
__u32 lgss_get_mic(
                struct gss_ctx          *ctx,
                int                      msgcnt,
                rawobj_t                *msgs,
                int                      iovcnt,
		struct bio_vec             *iovs,
                rawobj_t                *mic_token);
__u32 lgss_verify_mic(
                struct gss_ctx          *ctx,
                int                      msgcnt,
                rawobj_t                *msgs,
                int                      iovcnt,
		struct bio_vec             *iovs,
                rawobj_t                *mic_token);
__u32 lgss_wrap(
                struct gss_ctx          *ctx,
                rawobj_t                *gsshdr,
                rawobj_t                *msg,
                int                      msg_buflen,
                rawobj_t                *out_token);
__u32 lgss_unwrap(
                struct gss_ctx          *ctx,
                rawobj_t                *gsshdr,
                rawobj_t                *token,
                rawobj_t                *out_msg);
__u32 lgss_prep_bulk(
                struct gss_ctx          *gctx,
                struct ptlrpc_bulk_desc *desc);
__u32 lgss_wrap_bulk(
                struct gss_ctx          *gctx,
                struct ptlrpc_bulk_desc *desc,
                rawobj_t                *token,
                int                      adj_nob);
__u32 lgss_unwrap_bulk(
                struct gss_ctx          *gctx,
                struct ptlrpc_bulk_desc *desc,
                rawobj_t                *token,
                int                      adj_nob);
__u32 lgss_delete_sec_context(
                struct gss_ctx         **ctx);
int lgss_display(
                struct gss_ctx          *ctx,
                char                    *buf,
                int                      bufsize);

struct subflavor_desc {
        __u32           sf_subflavor;
        __u32           sf_qop;
        __u32           sf_service;
        char           *sf_name;
};

/* Each mechanism is described by the following struct: */
struct gss_api_mech {
	struct list_head	gm_list;
	struct module	       *gm_owner;
	char		       *gm_name;
	rawobj_t		gm_oid;
	atomic_t		gm_count;
	struct gss_api_ops     *gm_ops;
	int			gm_sf_num;
	struct subflavor_desc  *gm_sfs;
};

/* and must provide the following operations: */
struct gss_api_ops {
        __u32 (*gss_import_sec_context)(
                        rawobj_t               *input_token,
                        struct gss_ctx         *ctx);
        __u32 (*gss_copy_reverse_context)(
                        struct gss_ctx         *ctx,
                        struct gss_ctx         *ctx_new);
        __u32 (*gss_inquire_context)(
                        struct gss_ctx         *ctx,
			time64_t *endtime);
        __u32 (*gss_get_mic)(
                        struct gss_ctx         *ctx,
                        int                     msgcnt,
                        rawobj_t               *msgs,
                        int                     iovcnt,
			struct bio_vec         *iovs,
                        rawobj_t               *mic_token);
        __u32 (*gss_verify_mic)(
                        struct gss_ctx         *ctx,
                        int                     msgcnt,
                        rawobj_t               *msgs,
                        int                     iovcnt,
			struct bio_vec         *iovs,
                        rawobj_t               *mic_token);
        __u32 (*gss_wrap)(
                        struct gss_ctx         *ctx,
                        rawobj_t               *gsshdr,
                        rawobj_t               *msg,
                        int                     msg_buflen,
                        rawobj_t               *out_token);
        __u32 (*gss_unwrap)(
                        struct gss_ctx         *ctx,
                        rawobj_t               *gsshdr,
                        rawobj_t               *token,
                        rawobj_t               *out_msg);
        __u32 (*gss_prep_bulk)(
                        struct gss_ctx         *gctx,
                        struct ptlrpc_bulk_desc *desc);
        __u32 (*gss_wrap_bulk)(
                        struct gss_ctx         *gctx,
                        struct ptlrpc_bulk_desc *desc,
                        rawobj_t               *token,
                        int                     adj_nob);
        __u32 (*gss_unwrap_bulk)(
                        struct gss_ctx         *gctx,
                        struct ptlrpc_bulk_desc *desc,
                        rawobj_t               *token,
                        int                     adj_nob);
        void (*gss_delete_sec_context)(
                        void                   *ctx);
        int  (*gss_display)(
                        struct gss_ctx         *ctx,
                        char                   *buf,
                        int                     bufsize);
};

int lgss_mech_register(struct gss_api_mech *mech);
void lgss_mech_unregister(struct gss_api_mech *mech);

struct gss_api_mech * lgss_OID_to_mech(rawobj_t *oid);
struct gss_api_mech * lgss_name_to_mech(char *name);
struct gss_api_mech * lgss_subflavor_to_mech(__u32 subflavor);

struct gss_api_mech * lgss_mech_get(struct gss_api_mech *mech);
void lgss_mech_put(struct gss_api_mech *mech);

#endif /* __PTLRPC_GSS_GSS_API_H_ */
