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27#include <linux/init.h>
28#include <linux/module.h>
29#include <linux/crypto.h>
30#include <linux/zlib.h>
31#include <linux/vmalloc.h>
32#include <linux/interrupt.h>
33#include <linux/mm.h>
34#include <linux/net.h>
35#include <linux/slab.h>
36
37#define DEFLATE_DEF_LEVEL Z_DEFAULT_COMPRESSION
38#define DEFLATE_DEF_WINBITS 11
39#define DEFLATE_DEF_MEMLEVEL MAX_MEM_LEVEL
40
41struct deflate_ctx {
42 struct z_stream_s comp_stream;
43 struct z_stream_s decomp_stream;
44};
45
46static int deflate_comp_init(struct deflate_ctx *ctx)
47{
48 int ret = 0;
49 struct z_stream_s *stream = &ctx->comp_stream;
50
51 stream->workspace = vmalloc(zlib_deflate_workspacesize());
52 if (!stream->workspace ) {
53 ret = -ENOMEM;
54 goto out;
55 }
56 memset(stream->workspace, 0, zlib_deflate_workspacesize());
57 ret = zlib_deflateInit2(stream, DEFLATE_DEF_LEVEL, Z_DEFLATED,
58 -DEFLATE_DEF_WINBITS, DEFLATE_DEF_MEMLEVEL,
59 Z_DEFAULT_STRATEGY);
60 if (ret != Z_OK) {
61 ret = -EINVAL;
62 goto out_free;
63 }
64out:
65 return ret;
66out_free:
67 vfree(stream->workspace);
68 goto out;
69}
70
71static int deflate_decomp_init(struct deflate_ctx *ctx)
72{
73 int ret = 0;
74 struct z_stream_s *stream = &ctx->decomp_stream;
75
76 stream->workspace = kzalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
77 if (!stream->workspace ) {
78 ret = -ENOMEM;
79 goto out;
80 }
81 ret = zlib_inflateInit2(stream, -DEFLATE_DEF_WINBITS);
82 if (ret != Z_OK) {
83 ret = -EINVAL;
84 goto out_free;
85 }
86out:
87 return ret;
88out_free:
89 kfree(stream->workspace);
90 goto out;
91}
92
93static void deflate_comp_exit(struct deflate_ctx *ctx)
94{
95 zlib_deflateEnd(&ctx->comp_stream);
96 vfree(ctx->comp_stream.workspace);
97}
98
99static void deflate_decomp_exit(struct deflate_ctx *ctx)
100{
101 zlib_inflateEnd(&ctx->decomp_stream);
102 kfree(ctx->decomp_stream.workspace);
103}
104
105static int deflate_init(struct crypto_tfm *tfm)
106{
107 struct deflate_ctx *ctx = crypto_tfm_ctx(tfm);
108 int ret;
109
110 ret = deflate_comp_init(ctx);
111 if (ret)
112 goto out;
113 ret = deflate_decomp_init(ctx);
114 if (ret)
115 deflate_comp_exit(ctx);
116out:
117 return ret;
118}
119
120static void deflate_exit(struct crypto_tfm *tfm)
121{
122 struct deflate_ctx *ctx = crypto_tfm_ctx(tfm);
123
124 deflate_comp_exit(ctx);
125 deflate_decomp_exit(ctx);
126}
127
128static int deflate_compress(struct crypto_tfm *tfm, const u8 *src,
129 unsigned int slen, u8 *dst, unsigned int *dlen)
130{
131 int ret = 0;
132 struct deflate_ctx *dctx = crypto_tfm_ctx(tfm);
133 struct z_stream_s *stream = &dctx->comp_stream;
134
135 ret = zlib_deflateReset(stream);
136 if (ret != Z_OK) {
137 ret = -EINVAL;
138 goto out;
139 }
140
141 stream->next_in = (u8 *)src;
142 stream->avail_in = slen;
143 stream->next_out = (u8 *)dst;
144 stream->avail_out = *dlen;
145
146 ret = zlib_deflate(stream, Z_FINISH);
147 if (ret != Z_STREAM_END) {
148 ret = -EINVAL;
149 goto out;
150 }
151 ret = 0;
152 *dlen = stream->total_out;
153out:
154 return ret;
155}
156
157static int deflate_decompress(struct crypto_tfm *tfm, const u8 *src,
158 unsigned int slen, u8 *dst, unsigned int *dlen)
159{
160
161 int ret = 0;
162 struct deflate_ctx *dctx = crypto_tfm_ctx(tfm);
163 struct z_stream_s *stream = &dctx->decomp_stream;
164
165 ret = zlib_inflateReset(stream);
166 if (ret != Z_OK) {
167 ret = -EINVAL;
168 goto out;
169 }
170
171 stream->next_in = (u8 *)src;
172 stream->avail_in = slen;
173 stream->next_out = (u8 *)dst;
174 stream->avail_out = *dlen;
175
176 ret = zlib_inflate(stream, Z_SYNC_FLUSH);
177
178
179
180
181
182 if (ret == Z_OK && !stream->avail_in && stream->avail_out) {
183 u8 zerostuff = 0;
184 stream->next_in = &zerostuff;
185 stream->avail_in = 1;
186 ret = zlib_inflate(stream, Z_FINISH);
187 }
188 if (ret != Z_STREAM_END) {
189 ret = -EINVAL;
190 goto out;
191 }
192 ret = 0;
193 *dlen = stream->total_out;
194out:
195 return ret;
196}
197
198static struct crypto_alg alg = {
199 .cra_name = "deflate",
200 .cra_flags = CRYPTO_ALG_TYPE_COMPRESS,
201 .cra_ctxsize = sizeof(struct deflate_ctx),
202 .cra_module = THIS_MODULE,
203 .cra_list = LIST_HEAD_INIT(alg.cra_list),
204 .cra_init = deflate_init,
205 .cra_exit = deflate_exit,
206 .cra_u = { .compress = {
207 .coa_compress = deflate_compress,
208 .coa_decompress = deflate_decompress } }
209};
210
211static int __init deflate_mod_init(void)
212{
213 return crypto_register_alg(&alg);
214}
215
216static void __exit deflate_mod_fini(void)
217{
218 crypto_unregister_alg(&alg);
219}
220
221module_init(deflate_mod_init);
222module_exit(deflate_mod_fini);
223
224MODULE_LICENSE("GPL");
225MODULE_DESCRIPTION("Deflate Compression Algorithm for IPCOMP");
226MODULE_AUTHOR("James Morris <jmorris@intercode.com.au>");
227
228
