xref: /kernel/linux/linux-6.6/crypto/scompress.c (revision 62306a36) 
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Synchronous Compression operations
4 *
5 * Copyright 2015 LG Electronics Inc.
6 * Copyright (c) 2016, Intel Corporation
7 * Author: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
8 */
9
10#include <crypto/internal/acompress.h>
11#include <crypto/internal/scompress.h>
12#include <crypto/scatterwalk.h>
13#include <linux/cryptouser.h>
14#include <linux/err.h>
15#include <linux/kernel.h>
16#include <linux/module.h>
17#include <linux/scatterlist.h>
18#include <linux/seq_file.h>
19#include <linux/slab.h>
20#include <linux/string.h>
21#include <linux/vmalloc.h>
22#include <net/netlink.h>
23
24#include "compress.h"
25
26struct scomp_scratch {
27	spinlock_t	lock;
28	void		*src;
29	void		*dst;
30};
31
32static DEFINE_PER_CPU(struct scomp_scratch, scomp_scratch) = {
33	.lock = __SPIN_LOCK_UNLOCKED(scomp_scratch.lock),
34};
35
36static const struct crypto_type crypto_scomp_type;
37static int scomp_scratch_users;
38static DEFINE_MUTEX(scomp_lock);
39
40static int __maybe_unused crypto_scomp_report(
41	struct sk_buff *skb, struct crypto_alg *alg)
42{
43	struct crypto_report_comp rscomp;
44
45	memset(&rscomp, 0, sizeof(rscomp));
46
47	strscpy(rscomp.type, "scomp", sizeof(rscomp.type));
48
49	return nla_put(skb, CRYPTOCFGA_REPORT_COMPRESS,
50		       sizeof(rscomp), &rscomp);
51}
52
53static void crypto_scomp_show(struct seq_file *m, struct crypto_alg *alg)
54	__maybe_unused;
55
56static void crypto_scomp_show(struct seq_file *m, struct crypto_alg *alg)
57{
58	seq_puts(m, "type         : scomp\n");
59}
60
61static void crypto_scomp_free_scratches(void)
62{
63	struct scomp_scratch *scratch;
64	int i;
65
66	for_each_possible_cpu(i) {
67		scratch = per_cpu_ptr(&scomp_scratch, i);
68
69		vfree(scratch->src);
70		vfree(scratch->dst);
71		scratch->src = NULL;
72		scratch->dst = NULL;
73	}
74}
75
76static int crypto_scomp_alloc_scratches(void)
77{
78	struct scomp_scratch *scratch;
79	int i;
80
81	for_each_possible_cpu(i) {
82		void *mem;
83
84		scratch = per_cpu_ptr(&scomp_scratch, i);
85
86		mem = vmalloc_node(SCOMP_SCRATCH_SIZE, cpu_to_node(i));
87		if (!mem)
88			goto error;
89		scratch->src = mem;
90		mem = vmalloc_node(SCOMP_SCRATCH_SIZE, cpu_to_node(i));
91		if (!mem)
92			goto error;
93		scratch->dst = mem;
94	}
95	return 0;
96error:
97	crypto_scomp_free_scratches();
98	return -ENOMEM;
99}
100
101static int crypto_scomp_init_tfm(struct crypto_tfm *tfm)
102{
103	int ret = 0;
104
105	mutex_lock(&scomp_lock);
106	if (!scomp_scratch_users++)
107		ret = crypto_scomp_alloc_scratches();
108	mutex_unlock(&scomp_lock);
109
110	return ret;
111}
112
113static int scomp_acomp_comp_decomp(struct acomp_req *req, int dir)
114{
115	struct crypto_acomp *tfm = crypto_acomp_reqtfm(req);
116	void **tfm_ctx = acomp_tfm_ctx(tfm);
117	struct crypto_scomp *scomp = *tfm_ctx;
118	void **ctx = acomp_request_ctx(req);
119	struct scomp_scratch *scratch;
120	unsigned int dlen;
121	int ret;
122
123	if (!req->src || !req->slen || req->slen > SCOMP_SCRATCH_SIZE)
124		return -EINVAL;
125
126	if (req->dst && !req->dlen)
127		return -EINVAL;
128
129	if (!req->dlen || req->dlen > SCOMP_SCRATCH_SIZE)
130		req->dlen = SCOMP_SCRATCH_SIZE;
131
132	dlen = req->dlen;
133
134	scratch = raw_cpu_ptr(&scomp_scratch);
135	spin_lock(&scratch->lock);
136
137	scatterwalk_map_and_copy(scratch->src, req->src, 0, req->slen, 0);
138	if (dir)
139		ret = crypto_scomp_compress(scomp, scratch->src, req->slen,
140					    scratch->dst, &req->dlen, *ctx);
141	else
142		ret = crypto_scomp_decompress(scomp, scratch->src, req->slen,
143					      scratch->dst, &req->dlen, *ctx);
144	if (!ret) {
145		if (!req->dst) {
146			req->dst = sgl_alloc(req->dlen, GFP_ATOMIC, NULL);
147			if (!req->dst) {
148				ret = -ENOMEM;
149				goto out;
150			}
151		} else if (req->dlen > dlen) {
152			ret = -ENOSPC;
153			goto out;
154		}
155		scatterwalk_map_and_copy(scratch->dst, req->dst, 0, req->dlen,
156					 1);
157	}
158out:
159	spin_unlock(&scratch->lock);
160	return ret;
161}
162
163static int scomp_acomp_compress(struct acomp_req *req)
164{
165	return scomp_acomp_comp_decomp(req, 1);
166}
167
168static int scomp_acomp_decompress(struct acomp_req *req)
169{
170	return scomp_acomp_comp_decomp(req, 0);
171}
172
173static void crypto_exit_scomp_ops_async(struct crypto_tfm *tfm)
174{
175	struct crypto_scomp **ctx = crypto_tfm_ctx(tfm);
176
177	crypto_free_scomp(*ctx);
178
179	mutex_lock(&scomp_lock);
180	if (!--scomp_scratch_users)
181		crypto_scomp_free_scratches();
182	mutex_unlock(&scomp_lock);
183}
184
185int crypto_init_scomp_ops_async(struct crypto_tfm *tfm)
186{
187	struct crypto_alg *calg = tfm->__crt_alg;
188	struct crypto_acomp *crt = __crypto_acomp_tfm(tfm);
189	struct crypto_scomp **ctx = crypto_tfm_ctx(tfm);
190	struct crypto_scomp *scomp;
191
192	if (!crypto_mod_get(calg))
193		return -EAGAIN;
194
195	scomp = crypto_create_tfm(calg, &crypto_scomp_type);
196	if (IS_ERR(scomp)) {
197		crypto_mod_put(calg);
198		return PTR_ERR(scomp);
199	}
200
201	*ctx = scomp;
202	tfm->exit = crypto_exit_scomp_ops_async;
203
204	crt->compress = scomp_acomp_compress;
205	crt->decompress = scomp_acomp_decompress;
206	crt->dst_free = sgl_free;
207	crt->reqsize = sizeof(void *);
208
209	return 0;
210}
211
212struct acomp_req *crypto_acomp_scomp_alloc_ctx(struct acomp_req *req)
213{
214	struct crypto_acomp *acomp = crypto_acomp_reqtfm(req);
215	struct crypto_tfm *tfm = crypto_acomp_tfm(acomp);
216	struct crypto_scomp **tfm_ctx = crypto_tfm_ctx(tfm);
217	struct crypto_scomp *scomp = *tfm_ctx;
218	void *ctx;
219
220	ctx = crypto_scomp_alloc_ctx(scomp);
221	if (IS_ERR(ctx)) {
222		kfree(req);
223		return NULL;
224	}
225
226	*req->__ctx = ctx;
227
228	return req;
229}
230
231void crypto_acomp_scomp_free_ctx(struct acomp_req *req)
232{
233	struct crypto_acomp *acomp = crypto_acomp_reqtfm(req);
234	struct crypto_tfm *tfm = crypto_acomp_tfm(acomp);
235	struct crypto_scomp **tfm_ctx = crypto_tfm_ctx(tfm);
236	struct crypto_scomp *scomp = *tfm_ctx;
237	void *ctx = *req->__ctx;
238
239	if (ctx)
240		crypto_scomp_free_ctx(scomp, ctx);
241}
242
243static const struct crypto_type crypto_scomp_type = {
244	.extsize = crypto_alg_extsize,
245	.init_tfm = crypto_scomp_init_tfm,
246#ifdef CONFIG_PROC_FS
247	.show = crypto_scomp_show,
248#endif
249#if IS_ENABLED(CONFIG_CRYPTO_USER)
250	.report = crypto_scomp_report,
251#endif
252#ifdef CONFIG_CRYPTO_STATS
253	.report_stat = crypto_acomp_report_stat,
254#endif
255	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
256	.maskset = CRYPTO_ALG_TYPE_MASK,
257	.type = CRYPTO_ALG_TYPE_SCOMPRESS,
258	.tfmsize = offsetof(struct crypto_scomp, base),
259};
260
261int crypto_register_scomp(struct scomp_alg *alg)
262{
263	struct crypto_alg *base = &alg->calg.base;
264
265	comp_prepare_alg(&alg->calg);
266
267	base->cra_type = &crypto_scomp_type;
268	base->cra_flags |= CRYPTO_ALG_TYPE_SCOMPRESS;
269
270	return crypto_register_alg(base);
271}
272EXPORT_SYMBOL_GPL(crypto_register_scomp);
273
274void crypto_unregister_scomp(struct scomp_alg *alg)
275{
276	crypto_unregister_alg(&alg->base);
277}
278EXPORT_SYMBOL_GPL(crypto_unregister_scomp);
279
280int crypto_register_scomps(struct scomp_alg *algs, int count)
281{
282	int i, ret;
283
284	for (i = 0; i < count; i++) {
285		ret = crypto_register_scomp(&algs[i]);
286		if (ret)
287			goto err;
288	}
289
290	return 0;
291
292err:
293	for (--i; i >= 0; --i)
294		crypto_unregister_scomp(&algs[i]);
295
296	return ret;
297}
298EXPORT_SYMBOL_GPL(crypto_register_scomps);
299
300void crypto_unregister_scomps(struct scomp_alg *algs, int count)
301{
302	int i;
303
304	for (i = count - 1; i >= 0; --i)
305		crypto_unregister_scomp(&algs[i]);
306}
307EXPORT_SYMBOL_GPL(crypto_unregister_scomps);
308
309MODULE_LICENSE("GPL");
310MODULE_DESCRIPTION("Synchronous compression type");
311