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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Cryptographic API.
4 *
5 * RNG operations.
6 *
7 * Copyright (c) 2008 Neil Horman <nhorman@tuxdriver.com>
8 * Copyright (c) 2015 Herbert Xu <herbert@gondor.apana.org.au>
9 */
10
11#include <crypto/internal/rng.h>
12#include <linux/atomic.h>
13#include <linux/cryptouser.h>
14#include <linux/err.h>
15#include <linux/kernel.h>
16#include <linux/module.h>
17#include <linux/mutex.h>
18#include <linux/random.h>
19#include <linux/seq_file.h>
20#include <linux/slab.h>
21#include <linux/string.h>
22#include <net/netlink.h>
23
24#include "internal.h"
25
26static DEFINE_MUTEX(crypto_default_rng_lock);
27struct crypto_rng *crypto_default_rng;
28EXPORT_SYMBOL_GPL(crypto_default_rng);
29static int crypto_default_rng_refcnt;
30
31int crypto_rng_reset(struct crypto_rng *tfm, const u8 *seed, unsigned int slen)
32{
33 struct rng_alg *alg = crypto_rng_alg(tfm);
34 u8 *buf = NULL;
35 int err;
36
37 if (IS_ENABLED(CONFIG_CRYPTO_STATS))
38 atomic64_inc(&rng_get_stat(alg)->seed_cnt);
39
40 if (!seed && slen) {
41 buf = kmalloc(slen, GFP_KERNEL);
42 err = -ENOMEM;
43 if (!buf)
44 goto out;
45
46 err = get_random_bytes_wait(buf, slen);
47 if (err)
48 goto free_buf;
49 seed = buf;
50 }
51
52 err = alg->seed(tfm, seed, slen);
53free_buf:
54 kfree_sensitive(buf);
55out:
56 return crypto_rng_errstat(alg, err);
57}
58EXPORT_SYMBOL_GPL(crypto_rng_reset);
59
60static int crypto_rng_init_tfm(struct crypto_tfm *tfm)
61{
62 return 0;
63}
64
65static unsigned int seedsize(struct crypto_alg *alg)
66{
67 struct rng_alg *ralg = container_of(alg, struct rng_alg, base);
68
69 return ralg->seedsize;
70}
71
72static int __maybe_unused crypto_rng_report(
73 struct sk_buff *skb, struct crypto_alg *alg)
74{
75 struct crypto_report_rng rrng;
76
77 memset(&rrng, 0, sizeof(rrng));
78
79 strscpy(rrng.type, "rng", sizeof(rrng.type));
80
81 rrng.seedsize = seedsize(alg);
82
83 return nla_put(skb, CRYPTOCFGA_REPORT_RNG, sizeof(rrng), &rrng);
84}
85
86static void crypto_rng_show(struct seq_file *m, struct crypto_alg *alg)
87 __maybe_unused;
88static void crypto_rng_show(struct seq_file *m, struct crypto_alg *alg)
89{
90 seq_printf(m, "type : rng\n");
91 seq_printf(m, "seedsize : %u\n", seedsize(alg));
92}
93
94static int __maybe_unused crypto_rng_report_stat(
95 struct sk_buff *skb, struct crypto_alg *alg)
96{
97 struct rng_alg *rng = __crypto_rng_alg(alg);
98 struct crypto_istat_rng *istat;
99 struct crypto_stat_rng rrng;
100
101 istat = rng_get_stat(rng);
102
103 memset(&rrng, 0, sizeof(rrng));
104
105 strscpy(rrng.type, "rng", sizeof(rrng.type));
106
107 rrng.stat_generate_cnt = atomic64_read(&istat->generate_cnt);
108 rrng.stat_generate_tlen = atomic64_read(&istat->generate_tlen);
109 rrng.stat_seed_cnt = atomic64_read(&istat->seed_cnt);
110 rrng.stat_err_cnt = atomic64_read(&istat->err_cnt);
111
112 return nla_put(skb, CRYPTOCFGA_STAT_RNG, sizeof(rrng), &rrng);
113}
114
115static const struct crypto_type crypto_rng_type = {
116 .extsize = crypto_alg_extsize,
117 .init_tfm = crypto_rng_init_tfm,
118#ifdef CONFIG_PROC_FS
119 .show = crypto_rng_show,
120#endif
121#if IS_ENABLED(CONFIG_CRYPTO_USER)
122 .report = crypto_rng_report,
123#endif
124#ifdef CONFIG_CRYPTO_STATS
125 .report_stat = crypto_rng_report_stat,
126#endif
127 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
128 .maskset = CRYPTO_ALG_TYPE_MASK,
129 .type = CRYPTO_ALG_TYPE_RNG,
130 .tfmsize = offsetof(struct crypto_rng, base),
131};
132
133struct crypto_rng *crypto_alloc_rng(const char *alg_name, u32 type, u32 mask)
134{
135 return crypto_alloc_tfm(alg_name, &crypto_rng_type, type, mask);
136}
137EXPORT_SYMBOL_GPL(crypto_alloc_rng);
138
139int crypto_get_default_rng(void)
140{
141 struct crypto_rng *rng;
142 int err;
143
144 mutex_lock(&crypto_default_rng_lock);
145 if (!crypto_default_rng) {
146 rng = crypto_alloc_rng("stdrng", 0, 0);
147 err = PTR_ERR(rng);
148 if (IS_ERR(rng))
149 goto unlock;
150
151 err = crypto_rng_reset(rng, NULL, crypto_rng_seedsize(rng));
152 if (err) {
153 crypto_free_rng(rng);
154 goto unlock;
155 }
156
157 crypto_default_rng = rng;
158 }
159
160 crypto_default_rng_refcnt++;
161 err = 0;
162
163unlock:
164 mutex_unlock(&crypto_default_rng_lock);
165
166 return err;
167}
168EXPORT_SYMBOL_GPL(crypto_get_default_rng);
169
170void crypto_put_default_rng(void)
171{
172 mutex_lock(&crypto_default_rng_lock);
173 crypto_default_rng_refcnt--;
174 mutex_unlock(&crypto_default_rng_lock);
175}
176EXPORT_SYMBOL_GPL(crypto_put_default_rng);
177
178#if defined(CONFIG_CRYPTO_RNG) || defined(CONFIG_CRYPTO_RNG_MODULE)
179int crypto_del_default_rng(void)
180{
181 int err = -EBUSY;
182
183 mutex_lock(&crypto_default_rng_lock);
184 if (crypto_default_rng_refcnt)
185 goto out;
186
187 crypto_free_rng(crypto_default_rng);
188 crypto_default_rng = NULL;
189
190 err = 0;
191
192out:
193 mutex_unlock(&crypto_default_rng_lock);
194
195 return err;
196}
197EXPORT_SYMBOL_GPL(crypto_del_default_rng);
198#endif
199
200int crypto_register_rng(struct rng_alg *alg)
201{
202 struct crypto_istat_rng *istat = rng_get_stat(alg);
203 struct crypto_alg *base = &alg->base;
204
205 if (alg->seedsize > PAGE_SIZE / 8)
206 return -EINVAL;
207
208 base->cra_type = &crypto_rng_type;
209 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
210 base->cra_flags |= CRYPTO_ALG_TYPE_RNG;
211
212 if (IS_ENABLED(CONFIG_CRYPTO_STATS))
213 memset(istat, 0, sizeof(*istat));
214
215 return crypto_register_alg(base);
216}
217EXPORT_SYMBOL_GPL(crypto_register_rng);
218
219void crypto_unregister_rng(struct rng_alg *alg)
220{
221 crypto_unregister_alg(&alg->base);
222}
223EXPORT_SYMBOL_GPL(crypto_unregister_rng);
224
225int crypto_register_rngs(struct rng_alg *algs, int count)
226{
227 int i, ret;
228
229 for (i = 0; i < count; i++) {
230 ret = crypto_register_rng(algs + i);
231 if (ret)
232 goto err;
233 }
234
235 return 0;
236
237err:
238 for (--i; i >= 0; --i)
239 crypto_unregister_rng(algs + i);
240
241 return ret;
242}
243EXPORT_SYMBOL_GPL(crypto_register_rngs);
244
245void crypto_unregister_rngs(struct rng_alg *algs, int count)
246{
247 int i;
248
249 for (i = count - 1; i >= 0; --i)
250 crypto_unregister_rng(algs + i);
251}
252EXPORT_SYMBOL_GPL(crypto_unregister_rngs);
253
254MODULE_LICENSE("GPL");
255MODULE_DESCRIPTION("Random Number Generator");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Cryptographic API.
4 *
5 * RNG operations.
6 *
7 * Copyright (c) 2008 Neil Horman <nhorman@tuxdriver.com>
8 * Copyright (c) 2015 Herbert Xu <herbert@gondor.apana.org.au>
9 */
10
11#include <crypto/internal/rng.h>
12#include <linux/atomic.h>
13#include <linux/cryptouser.h>
14#include <linux/err.h>
15#include <linux/kernel.h>
16#include <linux/module.h>
17#include <linux/mutex.h>
18#include <linux/random.h>
19#include <linux/seq_file.h>
20#include <linux/slab.h>
21#include <linux/string.h>
22#include <net/netlink.h>
23
24#include "internal.h"
25
26static DEFINE_MUTEX(crypto_default_rng_lock);
27struct crypto_rng *crypto_default_rng;
28EXPORT_SYMBOL_GPL(crypto_default_rng);
29static int crypto_default_rng_refcnt;
30
31int crypto_rng_reset(struct crypto_rng *tfm, const u8 *seed, unsigned int slen)
32{
33 u8 *buf = NULL;
34 int err;
35
36 if (!seed && slen) {
37 buf = kmalloc(slen, GFP_KERNEL);
38 if (!buf)
39 return -ENOMEM;
40
41 err = get_random_bytes_wait(buf, slen);
42 if (err)
43 goto out;
44 seed = buf;
45 }
46
47 err = crypto_rng_alg(tfm)->seed(tfm, seed, slen);
48out:
49 kfree_sensitive(buf);
50 return err;
51}
52EXPORT_SYMBOL_GPL(crypto_rng_reset);
53
54static int crypto_rng_init_tfm(struct crypto_tfm *tfm)
55{
56 return 0;
57}
58
59static unsigned int seedsize(struct crypto_alg *alg)
60{
61 struct rng_alg *ralg = container_of(alg, struct rng_alg, base);
62
63 return ralg->seedsize;
64}
65
66static int __maybe_unused crypto_rng_report(
67 struct sk_buff *skb, struct crypto_alg *alg)
68{
69 struct crypto_report_rng rrng;
70
71 memset(&rrng, 0, sizeof(rrng));
72
73 strscpy(rrng.type, "rng", sizeof(rrng.type));
74
75 rrng.seedsize = seedsize(alg);
76
77 return nla_put(skb, CRYPTOCFGA_REPORT_RNG, sizeof(rrng), &rrng);
78}
79
80static void crypto_rng_show(struct seq_file *m, struct crypto_alg *alg)
81 __maybe_unused;
82static void crypto_rng_show(struct seq_file *m, struct crypto_alg *alg)
83{
84 seq_printf(m, "type : rng\n");
85 seq_printf(m, "seedsize : %u\n", seedsize(alg));
86}
87
88static const struct crypto_type crypto_rng_type = {
89 .extsize = crypto_alg_extsize,
90 .init_tfm = crypto_rng_init_tfm,
91#ifdef CONFIG_PROC_FS
92 .show = crypto_rng_show,
93#endif
94#if IS_ENABLED(CONFIG_CRYPTO_USER)
95 .report = crypto_rng_report,
96#endif
97 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
98 .maskset = CRYPTO_ALG_TYPE_MASK,
99 .type = CRYPTO_ALG_TYPE_RNG,
100 .tfmsize = offsetof(struct crypto_rng, base),
101};
102
103struct crypto_rng *crypto_alloc_rng(const char *alg_name, u32 type, u32 mask)
104{
105 return crypto_alloc_tfm(alg_name, &crypto_rng_type, type, mask);
106}
107EXPORT_SYMBOL_GPL(crypto_alloc_rng);
108
109int crypto_get_default_rng(void)
110{
111 struct crypto_rng *rng;
112 int err;
113
114 mutex_lock(&crypto_default_rng_lock);
115 if (!crypto_default_rng) {
116 rng = crypto_alloc_rng("stdrng", 0, 0);
117 err = PTR_ERR(rng);
118 if (IS_ERR(rng))
119 goto unlock;
120
121 err = crypto_rng_reset(rng, NULL, crypto_rng_seedsize(rng));
122 if (err) {
123 crypto_free_rng(rng);
124 goto unlock;
125 }
126
127 crypto_default_rng = rng;
128 }
129
130 crypto_default_rng_refcnt++;
131 err = 0;
132
133unlock:
134 mutex_unlock(&crypto_default_rng_lock);
135
136 return err;
137}
138EXPORT_SYMBOL_GPL(crypto_get_default_rng);
139
140void crypto_put_default_rng(void)
141{
142 mutex_lock(&crypto_default_rng_lock);
143 crypto_default_rng_refcnt--;
144 mutex_unlock(&crypto_default_rng_lock);
145}
146EXPORT_SYMBOL_GPL(crypto_put_default_rng);
147
148#if defined(CONFIG_CRYPTO_RNG) || defined(CONFIG_CRYPTO_RNG_MODULE)
149int crypto_del_default_rng(void)
150{
151 int err = -EBUSY;
152
153 mutex_lock(&crypto_default_rng_lock);
154 if (crypto_default_rng_refcnt)
155 goto out;
156
157 crypto_free_rng(crypto_default_rng);
158 crypto_default_rng = NULL;
159
160 err = 0;
161
162out:
163 mutex_unlock(&crypto_default_rng_lock);
164
165 return err;
166}
167EXPORT_SYMBOL_GPL(crypto_del_default_rng);
168#endif
169
170int crypto_register_rng(struct rng_alg *alg)
171{
172 struct crypto_alg *base = &alg->base;
173
174 if (alg->seedsize > PAGE_SIZE / 8)
175 return -EINVAL;
176
177 base->cra_type = &crypto_rng_type;
178 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
179 base->cra_flags |= CRYPTO_ALG_TYPE_RNG;
180
181 return crypto_register_alg(base);
182}
183EXPORT_SYMBOL_GPL(crypto_register_rng);
184
185void crypto_unregister_rng(struct rng_alg *alg)
186{
187 crypto_unregister_alg(&alg->base);
188}
189EXPORT_SYMBOL_GPL(crypto_unregister_rng);
190
191int crypto_register_rngs(struct rng_alg *algs, int count)
192{
193 int i, ret;
194
195 for (i = 0; i < count; i++) {
196 ret = crypto_register_rng(algs + i);
197 if (ret)
198 goto err;
199 }
200
201 return 0;
202
203err:
204 for (--i; i >= 0; --i)
205 crypto_unregister_rng(algs + i);
206
207 return ret;
208}
209EXPORT_SYMBOL_GPL(crypto_register_rngs);
210
211void crypto_unregister_rngs(struct rng_alg *algs, int count)
212{
213 int i;
214
215 for (i = count - 1; i >= 0; --i)
216 crypto_unregister_rng(algs + i);
217}
218EXPORT_SYMBOL_GPL(crypto_unregister_rngs);
219
220MODULE_LICENSE("GPL");
221MODULE_DESCRIPTION("Random Number Generator");