1/* SPDX-License-Identifier: GPL-2.0 */
2/* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */
3
4#ifndef _CRYPTO_COMMON_H
5#define _CRYPTO_COMMON_H
6
7#include "errno.h"
8#include <stdbool.h>
9
10struct bpf_crypto_ctx *bpf_crypto_ctx_create(const struct bpf_crypto_params *params,
11					     u32 params__sz, int *err) __ksym;
12struct bpf_crypto_ctx *bpf_crypto_ctx_acquire(struct bpf_crypto_ctx *ctx) __ksym;
13void bpf_crypto_ctx_release(struct bpf_crypto_ctx *ctx) __ksym;
14int bpf_crypto_encrypt(struct bpf_crypto_ctx *ctx, const struct bpf_dynptr *src,
15		       const struct bpf_dynptr *dst, const struct bpf_dynptr *iv) __ksym;
16int bpf_crypto_decrypt(struct bpf_crypto_ctx *ctx, const struct bpf_dynptr *src,
17		       const struct bpf_dynptr *dst, const struct bpf_dynptr *iv) __ksym;
18
19struct __crypto_ctx_value {
20	struct bpf_crypto_ctx __kptr * ctx;
21};
22
23struct array_map {
24	__uint(type, BPF_MAP_TYPE_ARRAY);
25	__type(key, int);
26	__type(value, struct __crypto_ctx_value);
27	__uint(max_entries, 1);
28} __crypto_ctx_map SEC(".maps");
29
30static inline struct __crypto_ctx_value *crypto_ctx_value_lookup(void)
31{
32	u32 key = 0;
33
34	return bpf_map_lookup_elem(&__crypto_ctx_map, &key);
35}
36
37static inline int crypto_ctx_insert(struct bpf_crypto_ctx *ctx)
38{
39	struct __crypto_ctx_value local, *v;
40	struct bpf_crypto_ctx *old;
41	u32 key = 0;
42	int err;
43
44	local.ctx = NULL;
45	err = bpf_map_update_elem(&__crypto_ctx_map, &key, &local, 0);
46	if (err) {
47		bpf_crypto_ctx_release(ctx);
48		return err;
49	}
50
51	v = bpf_map_lookup_elem(&__crypto_ctx_map, &key);
52	if (!v) {
53		bpf_crypto_ctx_release(ctx);
54		return -ENOENT;
55	}
56
57	old = bpf_kptr_xchg(&v->ctx, ctx);
58	if (old) {
59		bpf_crypto_ctx_release(old);
60		return -EEXIST;
61	}
62
63	return 0;
64}
65
66#endif /* _CRYPTO_COMMON_H */
67