1/*
2 * Synchronous Compression operations
3 *
4 * Copyright 2015 LG Electronics Inc.
5 * Copyright (c) 2016, Intel Corporation
6 * Author: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the Free
10 * Software Foundation; either version 2 of the License, or (at your option)
11 * any later version.
12 *
13 */
14#include <linux/errno.h>
15#include <linux/kernel.h>
16#include <linux/module.h>
17#include <linux/seq_file.h>
18#include <linux/slab.h>
19#include <linux/string.h>
20#include <linux/crypto.h>
21#include <linux/compiler.h>
22#include <linux/vmalloc.h>
23#include <crypto/algapi.h>
24#include <linux/cryptouser.h>
25#include <net/netlink.h>
26#include <linux/scatterlist.h>
27#include <crypto/scatterwalk.h>
28#include <crypto/internal/acompress.h>
29#include <crypto/internal/scompress.h>
30#include "internal.h"
31
32static const struct crypto_type crypto_scomp_type;
33static void * __percpu *scomp_src_scratches;
34static void * __percpu *scomp_dst_scratches;
35static int scomp_scratch_users;
36static DEFINE_MUTEX(scomp_lock);
37
38#ifdef CONFIG_NET
39static int crypto_scomp_report(struct sk_buff *skb, struct crypto_alg *alg)
40{
41 struct crypto_report_comp rscomp;
42
43 memset(&rscomp, 0, sizeof(rscomp));
44
45 strscpy(rscomp.type, "scomp", sizeof(rscomp.type));
46
47 return nla_put(skb, CRYPTOCFGA_REPORT_COMPRESS,
48 sizeof(rscomp), &rscomp);
49}
50#else
51static int crypto_scomp_report(struct sk_buff *skb, struct crypto_alg *alg)
52{
53 return -ENOSYS;
54}
55#endif
56
57static void crypto_scomp_show(struct seq_file *m, struct crypto_alg *alg)
58 __maybe_unused;
59
60static void crypto_scomp_show(struct seq_file *m, struct crypto_alg *alg)
61{
62 seq_puts(m, "type : scomp\n");
63}
64
65static void crypto_scomp_free_scratches(void * __percpu *scratches)
66{
67 int i;
68
69 if (!scratches)
70 return;
71
72 for_each_possible_cpu(i)
73 vfree(*per_cpu_ptr(scratches, i));
74
75 free_percpu(scratches);
76}
77
78static void * __percpu *crypto_scomp_alloc_scratches(void)
79{
80 void * __percpu *scratches;
81 int i;
82
83 scratches = alloc_percpu(void *);
84 if (!scratches)
85 return NULL;
86
87 for_each_possible_cpu(i) {
88 void *scratch;
89
90 scratch = vmalloc_node(SCOMP_SCRATCH_SIZE, cpu_to_node(i));
91 if (!scratch)
92 goto error;
93 *per_cpu_ptr(scratches, i) = scratch;
94 }
95
96 return scratches;
97
98error:
99 crypto_scomp_free_scratches(scratches);
100 return NULL;
101}
102
103static void crypto_scomp_free_all_scratches(void)
104{
105 if (!--scomp_scratch_users) {
106 crypto_scomp_free_scratches(scomp_src_scratches);
107 crypto_scomp_free_scratches(scomp_dst_scratches);
108 scomp_src_scratches = NULL;
109 scomp_dst_scratches = NULL;
110 }
111}
112
113static int crypto_scomp_alloc_all_scratches(void)
114{
115 if (!scomp_scratch_users++) {
116 scomp_src_scratches = crypto_scomp_alloc_scratches();
117 if (!scomp_src_scratches)
118 return -ENOMEM;
119 scomp_dst_scratches = crypto_scomp_alloc_scratches();
120 if (!scomp_dst_scratches) {
121 crypto_scomp_free_scratches(scomp_src_scratches);
122 scomp_src_scratches = NULL;
123 return -ENOMEM;
124 }
125 }
126 return 0;
127}
128
129static int crypto_scomp_init_tfm(struct crypto_tfm *tfm)
130{
131 int ret;
132
133 mutex_lock(&scomp_lock);
134 ret = crypto_scomp_alloc_all_scratches();
135 mutex_unlock(&scomp_lock);
136
137 return ret;
138}
139
140static int scomp_acomp_comp_decomp(struct acomp_req *req, int dir)
141{
142 struct crypto_acomp *tfm = crypto_acomp_reqtfm(req);
143 void **tfm_ctx = acomp_tfm_ctx(tfm);
144 struct crypto_scomp *scomp = *tfm_ctx;
145 void **ctx = acomp_request_ctx(req);
146 const int cpu = get_cpu();
147 u8 *scratch_src = *per_cpu_ptr(scomp_src_scratches, cpu);
148 u8 *scratch_dst = *per_cpu_ptr(scomp_dst_scratches, cpu);
149 int ret;
150
151 if (!req->src || !req->slen || req->slen > SCOMP_SCRATCH_SIZE) {
152 ret = -EINVAL;
153 goto out;
154 }
155
156 if (req->dst && !req->dlen) {
157 ret = -EINVAL;
158 goto out;
159 }
160
161 if (!req->dlen || req->dlen > SCOMP_SCRATCH_SIZE)
162 req->dlen = SCOMP_SCRATCH_SIZE;
163
164 scatterwalk_map_and_copy(scratch_src, req->src, 0, req->slen, 0);
165 if (dir)
166 ret = crypto_scomp_compress(scomp, scratch_src, req->slen,
167 scratch_dst, &req->dlen, *ctx);
168 else
169 ret = crypto_scomp_decompress(scomp, scratch_src, req->slen,
170 scratch_dst, &req->dlen, *ctx);
171 if (!ret) {
172 if (!req->dst) {
173 req->dst = sgl_alloc(req->dlen, GFP_ATOMIC, NULL);
174 if (!req->dst)
175 goto out;
176 }
177 scatterwalk_map_and_copy(scratch_dst, req->dst, 0, req->dlen,
178 1);
179 }
180out:
181 put_cpu();
182 return ret;
183}
184
185static int scomp_acomp_compress(struct acomp_req *req)
186{
187 return scomp_acomp_comp_decomp(req, 1);
188}
189
190static int scomp_acomp_decompress(struct acomp_req *req)
191{
192 return scomp_acomp_comp_decomp(req, 0);
193}
194
195static void crypto_exit_scomp_ops_async(struct crypto_tfm *tfm)
196{
197 struct crypto_scomp **ctx = crypto_tfm_ctx(tfm);
198
199 crypto_free_scomp(*ctx);
200
201 mutex_lock(&scomp_lock);
202 crypto_scomp_free_all_scratches();
203 mutex_unlock(&scomp_lock);
204}
205
206int crypto_init_scomp_ops_async(struct crypto_tfm *tfm)
207{
208 struct crypto_alg *calg = tfm->__crt_alg;
209 struct crypto_acomp *crt = __crypto_acomp_tfm(tfm);
210 struct crypto_scomp **ctx = crypto_tfm_ctx(tfm);
211 struct crypto_scomp *scomp;
212
213 if (!crypto_mod_get(calg))
214 return -EAGAIN;
215
216 scomp = crypto_create_tfm(calg, &crypto_scomp_type);
217 if (IS_ERR(scomp)) {
218 crypto_mod_put(calg);
219 return PTR_ERR(scomp);
220 }
221
222 *ctx = scomp;
223 tfm->exit = crypto_exit_scomp_ops_async;
224
225 crt->compress = scomp_acomp_compress;
226 crt->decompress = scomp_acomp_decompress;
227 crt->dst_free = sgl_free;
228 crt->reqsize = sizeof(void *);
229
230 return 0;
231}
232
233struct acomp_req *crypto_acomp_scomp_alloc_ctx(struct acomp_req *req)
234{
235 struct crypto_acomp *acomp = crypto_acomp_reqtfm(req);
236 struct crypto_tfm *tfm = crypto_acomp_tfm(acomp);
237 struct crypto_scomp **tfm_ctx = crypto_tfm_ctx(tfm);
238 struct crypto_scomp *scomp = *tfm_ctx;
239 void *ctx;
240
241 ctx = crypto_scomp_alloc_ctx(scomp);
242 if (IS_ERR(ctx)) {
243 kfree(req);
244 return NULL;
245 }
246
247 *req->__ctx = ctx;
248
249 return req;
250}
251
252void crypto_acomp_scomp_free_ctx(struct acomp_req *req)
253{
254 struct crypto_acomp *acomp = crypto_acomp_reqtfm(req);
255 struct crypto_tfm *tfm = crypto_acomp_tfm(acomp);
256 struct crypto_scomp **tfm_ctx = crypto_tfm_ctx(tfm);
257 struct crypto_scomp *scomp = *tfm_ctx;
258 void *ctx = *req->__ctx;
259
260 if (ctx)
261 crypto_scomp_free_ctx(scomp, ctx);
262}
263
264static const struct crypto_type crypto_scomp_type = {
265 .extsize = crypto_alg_extsize,
266 .init_tfm = crypto_scomp_init_tfm,
267#ifdef CONFIG_PROC_FS
268 .show = crypto_scomp_show,
269#endif
270 .report = crypto_scomp_report,
271 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
272 .maskset = CRYPTO_ALG_TYPE_MASK,
273 .type = CRYPTO_ALG_TYPE_SCOMPRESS,
274 .tfmsize = offsetof(struct crypto_scomp, base),
275};
276
277int crypto_register_scomp(struct scomp_alg *alg)
278{
279 struct crypto_alg *base = &alg->base;
280
281 base->cra_type = &crypto_scomp_type;
282 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
283 base->cra_flags |= CRYPTO_ALG_TYPE_SCOMPRESS;
284
285 return crypto_register_alg(base);
286}
287EXPORT_SYMBOL_GPL(crypto_register_scomp);
288
289int crypto_unregister_scomp(struct scomp_alg *alg)
290{
291 return crypto_unregister_alg(&alg->base);
292}
293EXPORT_SYMBOL_GPL(crypto_unregister_scomp);
294
295int crypto_register_scomps(struct scomp_alg *algs, int count)
296{
297 int i, ret;
298
299 for (i = 0; i < count; i++) {
300 ret = crypto_register_scomp(&algs[i]);
301 if (ret)
302 goto err;
303 }
304
305 return 0;
306
307err:
308 for (--i; i >= 0; --i)
309 crypto_unregister_scomp(&algs[i]);
310
311 return ret;
312}
313EXPORT_SYMBOL_GPL(crypto_register_scomps);
314
315void crypto_unregister_scomps(struct scomp_alg *algs, int count)
316{
317 int i;
318
319 for (i = count - 1; i >= 0; --i)
320 crypto_unregister_scomp(&algs[i]);
321}
322EXPORT_SYMBOL_GPL(crypto_unregister_scomps);
323
324MODULE_LICENSE("GPL");
325MODULE_DESCRIPTION("Synchronous compression type");
326