/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */

#ifndef _CRYPTO_COMMON_H
#define _CRYPTO_COMMON_H

#include "errno.h"
#include <stdbool.h>

struct bpf_crypto_ctx *bpf_crypto_ctx_create(const struct bpf_crypto_params *params,
                                             u32 params__sz, int *err) __ksym;
struct bpf_crypto_ctx *bpf_crypto_ctx_acquire(struct bpf_crypto_ctx *ctx) __ksym;
void bpf_crypto_ctx_release(struct bpf_crypto_ctx *ctx) __ksym;
int bpf_crypto_encrypt(struct bpf_crypto_ctx *ctx, const struct bpf_dynptr *src,
                       const struct bpf_dynptr *dst, const struct bpf_dynptr *iv) __ksym;
int bpf_crypto_decrypt(struct bpf_crypto_ctx *ctx, const struct bpf_dynptr *src,
                       const struct bpf_dynptr *dst, const struct bpf_dynptr *iv) __ksym;

struct __crypto_ctx_value {
        struct bpf_crypto_ctx __kptr * ctx;
};

struct array_map {
        __uint(type, BPF_MAP_TYPE_ARRAY);
        __type(key, int);
        __type(value, struct __crypto_ctx_value);
        __uint(max_entries, 1);
} __crypto_ctx_map SEC(".maps");

static inline struct __crypto_ctx_value *crypto_ctx_value_lookup(void)
{
        u32 key = 0;

        return bpf_map_lookup_elem(&__crypto_ctx_map, &key);
}

static inline int crypto_ctx_insert(struct bpf_crypto_ctx *ctx)
{
        struct __crypto_ctx_value local, *v;
        struct bpf_crypto_ctx *old;
        u32 key = 0;
        int err;

        local.ctx = NULL;
        err = bpf_map_update_elem(&__crypto_ctx_map, &key, &local, 0);
        if (err) {
                bpf_crypto_ctx_release(ctx);
                return err;
        }

        v = bpf_map_lookup_elem(&__crypto_ctx_map, &key);
        if (!v) {
                bpf_crypto_ctx_release(ctx);
                return -ENOENT;
        }

        old = bpf_kptr_xchg(&v->ctx, ctx);
        if (old) {
                bpf_crypto_ctx_release(old);
                return -EEXIST;
        }

        return 0;
}

#endif /* _CRYPTO_COMMON_H */