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19#include <linux/init.h>
20#include <linux/module.h>
21#include <linux/crypto.h>
22#include <linux/vmalloc.h>
23#include <linux/mm.h>
24#include <linux/lzo.h>
25
26struct lzo_ctx {
27 void *lzo_comp_mem;
28};
29
30static int lzo_init(struct crypto_tfm *tfm)
31{
32 struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);
33
34 ctx->lzo_comp_mem = kmalloc(LZO1X_MEM_COMPRESS,
35 GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
36 if (!ctx->lzo_comp_mem)
37 ctx->lzo_comp_mem = vmalloc(LZO1X_MEM_COMPRESS);
38 if (!ctx->lzo_comp_mem)
39 return -ENOMEM;
40
41 return 0;
42}
43
44static void lzo_exit(struct crypto_tfm *tfm)
45{
46 struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);
47
48 kvfree(ctx->lzo_comp_mem);
49}
50
51static int lzo_compress(struct crypto_tfm *tfm, const u8 *src,
52 unsigned int slen, u8 *dst, unsigned int *dlen)
53{
54 struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);
55 size_t tmp_len = *dlen;
56 int err;
57
58 err = lzo1x_1_compress(src, slen, dst, &tmp_len, ctx->lzo_comp_mem);
59
60 if (err != LZO_E_OK)
61 return -EINVAL;
62
63 *dlen = tmp_len;
64 return 0;
65}
66
67static int lzo_decompress(struct crypto_tfm *tfm, const u8 *src,
68 unsigned int slen, u8 *dst, unsigned int *dlen)
69{
70 int err;
71 size_t tmp_len = *dlen;
72
73 err = lzo1x_decompress_safe(src, slen, dst, &tmp_len);
74
75 if (err != LZO_E_OK)
76 return -EINVAL;
77
78 *dlen = tmp_len;
79 return 0;
80
81}
82
83static struct crypto_alg alg = {
84 .cra_name = "lzo",
85 .cra_flags = CRYPTO_ALG_TYPE_COMPRESS,
86 .cra_ctxsize = sizeof(struct lzo_ctx),
87 .cra_module = THIS_MODULE,
88 .cra_init = lzo_init,
89 .cra_exit = lzo_exit,
90 .cra_u = { .compress = {
91 .coa_compress = lzo_compress,
92 .coa_decompress = lzo_decompress } }
93};
94
95static int __init lzo_mod_init(void)
96{
97 return crypto_register_alg(&alg);
98}
99
100static void __exit lzo_mod_fini(void)
101{
102 crypto_unregister_alg(&alg);
103}
104
105module_init(lzo_mod_init);
106module_exit(lzo_mod_fini);
107
108MODULE_LICENSE("GPL");
109MODULE_DESCRIPTION("LZO Compression Algorithm");
110MODULE_ALIAS_CRYPTO("lzo");
111