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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_getParams(ZSTD_DEF_LEVEL, 0, 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_CCtxWorkspaceBound(params.cParams);
37
38 ctx->cwksp = vzalloc(wksp_size);
39 if (!ctx->cwksp) {
40 ret = -ENOMEM;
41 goto out;
42 }
43
44 ctx->cctx = ZSTD_initCCtx(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_DCtxWorkspaceBound();
60
61 ctx->dwksp = vzalloc(wksp_size);
62 if (!ctx->dwksp) {
63 ret = -ENOMEM;
64 goto out;
65 }
66
67 ctx->dctx = ZSTD_initDCtx(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(struct crypto_scomp *tfm)
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 int zstd_init(struct crypto_tfm *tfm)
125{
126 struct zstd_ctx *ctx = crypto_tfm_ctx(tfm);
127
128 return __zstd_init(ctx);
129}
130
131static void __zstd_exit(void *ctx)
132{
133 zstd_comp_exit(ctx);
134 zstd_decomp_exit(ctx);
135}
136
137static void zstd_free_ctx(struct crypto_scomp *tfm, void *ctx)
138{
139 __zstd_exit(ctx);
140 kfree_sensitive(ctx);
141}
142
143static void zstd_exit(struct crypto_tfm *tfm)
144{
145 struct zstd_ctx *ctx = crypto_tfm_ctx(tfm);
146
147 __zstd_exit(ctx);
148}
149
150static int __zstd_compress(const u8 *src, unsigned int slen,
151 u8 *dst, unsigned int *dlen, void *ctx)
152{
153 size_t out_len;
154 struct zstd_ctx *zctx = ctx;
155 const ZSTD_parameters params = zstd_params();
156
157 out_len = ZSTD_compressCCtx(zctx->cctx, dst, *dlen, src, slen, params);
158 if (ZSTD_isError(out_len))
159 return -EINVAL;
160 *dlen = out_len;
161 return 0;
162}
163
164static int zstd_compress(struct crypto_tfm *tfm, const u8 *src,
165 unsigned int slen, u8 *dst, unsigned int *dlen)
166{
167 struct zstd_ctx *ctx = crypto_tfm_ctx(tfm);
168
169 return __zstd_compress(src, slen, dst, dlen, ctx);
170}
171
172static int zstd_scompress(struct crypto_scomp *tfm, const u8 *src,
173 unsigned int slen, u8 *dst, unsigned int *dlen,
174 void *ctx)
175{
176 return __zstd_compress(src, slen, dst, dlen, ctx);
177}
178
179static int __zstd_decompress(const u8 *src, unsigned int slen,
180 u8 *dst, unsigned int *dlen, void *ctx)
181{
182 size_t out_len;
183 struct zstd_ctx *zctx = ctx;
184
185 out_len = ZSTD_decompressDCtx(zctx->dctx, dst, *dlen, src, slen);
186 if (ZSTD_isError(out_len))
187 return -EINVAL;
188 *dlen = out_len;
189 return 0;
190}
191
192static int zstd_decompress(struct crypto_tfm *tfm, const u8 *src,
193 unsigned int slen, u8 *dst, unsigned int *dlen)
194{
195 struct zstd_ctx *ctx = crypto_tfm_ctx(tfm);
196
197 return __zstd_decompress(src, slen, dst, dlen, ctx);
198}
199
200static int zstd_sdecompress(struct crypto_scomp *tfm, const u8 *src,
201 unsigned int slen, u8 *dst, unsigned int *dlen,
202 void *ctx)
203{
204 return __zstd_decompress(src, slen, dst, dlen, ctx);
205}
206
207static struct crypto_alg alg = {
208 .cra_name = "zstd",
209 .cra_driver_name = "zstd-generic",
210 .cra_flags = CRYPTO_ALG_TYPE_COMPRESS,
211 .cra_ctxsize = sizeof(struct zstd_ctx),
212 .cra_module = THIS_MODULE,
213 .cra_init = zstd_init,
214 .cra_exit = zstd_exit,
215 .cra_u = { .compress = {
216 .coa_compress = zstd_compress,
217 .coa_decompress = zstd_decompress } }
218};
219
220static struct scomp_alg scomp = {
221 .alloc_ctx = zstd_alloc_ctx,
222 .free_ctx = zstd_free_ctx,
223 .compress = zstd_scompress,
224 .decompress = zstd_sdecompress,
225 .base = {
226 .cra_name = "zstd",
227 .cra_driver_name = "zstd-scomp",
228 .cra_module = THIS_MODULE,
229 }
230};
231
232static int __init zstd_mod_init(void)
233{
234 int ret;
235
236 ret = crypto_register_alg(&alg);
237 if (ret)
238 return ret;
239
240 ret = crypto_register_scomp(&scomp);
241 if (ret)
242 crypto_unregister_alg(&alg);
243
244 return ret;
245}
246
247static void __exit zstd_mod_fini(void)
248{
249 crypto_unregister_alg(&alg);
250 crypto_unregister_scomp(&scomp);
251}
252
253subsys_initcall(zstd_mod_init);
254module_exit(zstd_mod_fini);
255
256MODULE_LICENSE("GPL");
257MODULE_DESCRIPTION("Zstd Compression Algorithm");
258MODULE_ALIAS_CRYPTO("zstd");
259
