~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/crypto/rng.c

Version: ~ [ linux-5.3-rc5 ] ~ [ linux-5.2.9 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.67 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.139 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.189 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.189 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.72 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /*
  2  * Cryptographic API.
  3  *
  4  * RNG operations.
  5  *
  6  * Copyright (c) 2008 Neil Horman <nhorman@tuxdriver.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 
 15 #include <linux/atomic.h>
 16 #include <crypto/internal/rng.h>
 17 #include <linux/err.h>
 18 #include <linux/module.h>
 19 #include <linux/mutex.h>
 20 #include <linux/random.h>
 21 #include <linux/seq_file.h>
 22 #include <linux/slab.h>
 23 #include <linux/string.h>
 24 #include <linux/cryptouser.h>
 25 #include <net/netlink.h>
 26 
 27 static DEFINE_MUTEX(crypto_default_rng_lock);
 28 struct crypto_rng *crypto_default_rng;
 29 EXPORT_SYMBOL_GPL(crypto_default_rng);
 30 static int crypto_default_rng_refcnt;
 31 
 32 static int rngapi_reset(struct crypto_rng *tfm, u8 *seed, unsigned int slen)
 33 {
 34         u8 *buf = NULL;
 35         int err;
 36 
 37         if (!seed && slen) {
 38                 buf = kmalloc(slen, GFP_KERNEL);
 39                 if (!buf)
 40                         return -ENOMEM;
 41 
 42                 get_random_bytes(buf, slen);
 43                 seed = buf;
 44         }
 45 
 46         err = crypto_rng_alg(tfm)->rng_reset(tfm, seed, slen);
 47 
 48         kfree(buf);
 49         return err;
 50 }
 51 
 52 static int crypto_init_rng_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
 53 {
 54         struct rng_alg *alg = &tfm->__crt_alg->cra_rng;
 55         struct rng_tfm *ops = &tfm->crt_rng;
 56 
 57         ops->rng_gen_random = alg->rng_make_random;
 58         ops->rng_reset = rngapi_reset;
 59 
 60         return 0;
 61 }
 62 
 63 #ifdef CONFIG_NET
 64 static int crypto_rng_report(struct sk_buff *skb, struct crypto_alg *alg)
 65 {
 66         struct crypto_report_rng rrng;
 67 
 68         strncpy(rrng.type, "rng", sizeof(rrng.type));
 69 
 70         rrng.seedsize = alg->cra_rng.seedsize;
 71 
 72         if (nla_put(skb, CRYPTOCFGA_REPORT_RNG,
 73                     sizeof(struct crypto_report_rng), &rrng))
 74                 goto nla_put_failure;
 75         return 0;
 76 
 77 nla_put_failure:
 78         return -EMSGSIZE;
 79 }
 80 #else
 81 static int crypto_rng_report(struct sk_buff *skb, struct crypto_alg *alg)
 82 {
 83         return -ENOSYS;
 84 }
 85 #endif
 86 
 87 static void crypto_rng_show(struct seq_file *m, struct crypto_alg *alg)
 88         __attribute__ ((unused));
 89 static void crypto_rng_show(struct seq_file *m, struct crypto_alg *alg)
 90 {
 91         seq_printf(m, "type         : rng\n");
 92         seq_printf(m, "seedsize     : %u\n", alg->cra_rng.seedsize);
 93 }
 94 
 95 static unsigned int crypto_rng_ctxsize(struct crypto_alg *alg, u32 type,
 96                                        u32 mask)
 97 {
 98         return alg->cra_ctxsize;
 99 }
100 
101 const struct crypto_type crypto_rng_type = {
102         .ctxsize = crypto_rng_ctxsize,
103         .init = crypto_init_rng_ops,
104 #ifdef CONFIG_PROC_FS
105         .show = crypto_rng_show,
106 #endif
107         .report = crypto_rng_report,
108 };
109 EXPORT_SYMBOL_GPL(crypto_rng_type);
110 
111 int crypto_get_default_rng(void)
112 {
113         struct crypto_rng *rng;
114         int err;
115 
116         mutex_lock(&crypto_default_rng_lock);
117         if (!crypto_default_rng) {
118                 rng = crypto_alloc_rng("stdrng", 0, 0);
119                 err = PTR_ERR(rng);
120                 if (IS_ERR(rng))
121                         goto unlock;
122 
123                 err = crypto_rng_reset(rng, NULL, crypto_rng_seedsize(rng));
124                 if (err) {
125                         crypto_free_rng(rng);
126                         goto unlock;
127                 }
128 
129                 crypto_default_rng = rng;
130         }
131 
132         crypto_default_rng_refcnt++;
133         err = 0;
134 
135 unlock:
136         mutex_unlock(&crypto_default_rng_lock);
137 
138         return err;
139 }
140 EXPORT_SYMBOL_GPL(crypto_get_default_rng);
141 
142 void crypto_put_default_rng(void)
143 {
144         mutex_lock(&crypto_default_rng_lock);
145         if (!--crypto_default_rng_refcnt) {
146                 crypto_free_rng(crypto_default_rng);
147                 crypto_default_rng = NULL;
148         }
149         mutex_unlock(&crypto_default_rng_lock);
150 }
151 EXPORT_SYMBOL_GPL(crypto_put_default_rng);
152 
153 MODULE_LICENSE("GPL");
154 MODULE_DESCRIPTION("Random Number Generator");
155 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp