Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Cryptographic API.
4 *
5 * Copyright (c) 2017-present, Facebook, Inc.
6 */
7#include <linux/crypto.h>
8#include <linux/init.h>
9#include <linux/interrupt.h>
10#include <linux/mm.h>
11#include <linux/module.h>
12#include <linux/net.h>
13#include <linux/vmalloc.h>
14#include <linux/zstd.h>
15#include <crypto/internal/scompress.h>
16
17
18#define ZSTD_DEF_LEVEL 3
19
20struct zstd_ctx {
21 zstd_cctx *cctx;
22 zstd_dctx *dctx;
23 void *cwksp;
24 void *dwksp;
25};
26
27static zstd_parameters zstd_params(void)
28{
29 return zstd_get_params(ZSTD_DEF_LEVEL, 0);
30}
31
32static int zstd_comp_init(struct zstd_ctx *ctx)
33{
34 int ret = 0;
35 const zstd_parameters params = zstd_params();
36 const size_t wksp_size = zstd_cctx_workspace_bound(¶ms.cParams);
37
38 ctx->cwksp = vzalloc(wksp_size);
39 if (!ctx->cwksp) {
40 ret = -ENOMEM;
41 goto out;
42 }
43
44 ctx->cctx = zstd_init_cctx(ctx->cwksp, wksp_size);
45 if (!ctx->cctx) {
46 ret = -EINVAL;
47 goto out_free;
48 }
49out:
50 return ret;
51out_free:
52 vfree(ctx->cwksp);
53 goto out;
54}
55
56static int zstd_decomp_init(struct zstd_ctx *ctx)
57{
58 int ret = 0;
59 const size_t wksp_size = zstd_dctx_workspace_bound();
60
61 ctx->dwksp = vzalloc(wksp_size);
62 if (!ctx->dwksp) {
63 ret = -ENOMEM;
64 goto out;
65 }
66
67 ctx->dctx = zstd_init_dctx(ctx->dwksp, wksp_size);
68 if (!ctx->dctx) {
69 ret = -EINVAL;
70 goto out_free;
71 }
72out:
73 return ret;
74out_free:
75 vfree(ctx->dwksp);
76 goto out;
77}
78
79static void zstd_comp_exit(struct zstd_ctx *ctx)
80{
81 vfree(ctx->cwksp);
82 ctx->cwksp = NULL;
83 ctx->cctx = NULL;
84}
85
86static void zstd_decomp_exit(struct zstd_ctx *ctx)
87{
88 vfree(ctx->dwksp);
89 ctx->dwksp = NULL;
90 ctx->dctx = NULL;
91}
92
93static int __zstd_init(void *ctx)
94{
95 int ret;
96
97 ret = zstd_comp_init(ctx);
98 if (ret)
99 return ret;
100 ret = zstd_decomp_init(ctx);
101 if (ret)
102 zstd_comp_exit(ctx);
103 return ret;
104}
105
106static void *zstd_alloc_ctx(void)
107{
108 int ret;
109 struct zstd_ctx *ctx;
110
111 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
112 if (!ctx)
113 return ERR_PTR(-ENOMEM);
114
115 ret = __zstd_init(ctx);
116 if (ret) {
117 kfree(ctx);
118 return ERR_PTR(ret);
119 }
120
121 return ctx;
122}
123
124static void __zstd_exit(void *ctx)
125{
126 zstd_comp_exit(ctx);
127 zstd_decomp_exit(ctx);
128}
129
130static void zstd_free_ctx(void *ctx)
131{
132 __zstd_exit(ctx);
133 kfree_sensitive(ctx);
134}
135
136static int __zstd_compress(const u8 *src, unsigned int slen,
137 u8 *dst, unsigned int *dlen, void *ctx)
138{
139 size_t out_len;
140 struct zstd_ctx *zctx = ctx;
141 const zstd_parameters params = zstd_params();
142
143 out_len = zstd_compress_cctx(zctx->cctx, dst, *dlen, src, slen, ¶ms);
144 if (zstd_is_error(out_len))
145 return -EINVAL;
146 *dlen = out_len;
147 return 0;
148}
149
150static int zstd_scompress(struct crypto_scomp *tfm, const u8 *src,
151 unsigned int slen, u8 *dst, unsigned int *dlen,
152 void *ctx)
153{
154 return __zstd_compress(src, slen, dst, dlen, ctx);
155}
156
157static int __zstd_decompress(const u8 *src, unsigned int slen,
158 u8 *dst, unsigned int *dlen, void *ctx)
159{
160 size_t out_len;
161 struct zstd_ctx *zctx = ctx;
162
163 out_len = zstd_decompress_dctx(zctx->dctx, dst, *dlen, src, slen);
164 if (zstd_is_error(out_len))
165 return -EINVAL;
166 *dlen = out_len;
167 return 0;
168}
169
170static int zstd_sdecompress(struct crypto_scomp *tfm, const u8 *src,
171 unsigned int slen, u8 *dst, unsigned int *dlen,
172 void *ctx)
173{
174 return __zstd_decompress(src, slen, dst, dlen, ctx);
175}
176
177static struct scomp_alg scomp = {
178 .alloc_ctx = zstd_alloc_ctx,
179 .free_ctx = zstd_free_ctx,
180 .compress = zstd_scompress,
181 .decompress = zstd_sdecompress,
182 .base = {
183 .cra_name = "zstd",
184 .cra_driver_name = "zstd-scomp",
185 .cra_module = THIS_MODULE,
186 }
187};
188
189static int __init zstd_mod_init(void)
190{
191 return crypto_register_scomp(&scomp);
192}
193
194static void __exit zstd_mod_fini(void)
195{
196 crypto_unregister_scomp(&scomp);
197}
198
199module_init(zstd_mod_init);
200module_exit(zstd_mod_fini);
201
202MODULE_LICENSE("GPL");
203MODULE_DESCRIPTION("Zstd Compression Algorithm");
204MODULE_ALIAS_CRYPTO("zstd");