Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: Revert crypto: prng - Deterministic CPRNG
This commit is contained in:
Linus Torvalds
commit
260eddf439
|
|
@ -666,15 +666,6 @@ config CRYPTO_LZO
|
|||
help
|
||||
This is the LZO algorithm.
|
||||
|
||||
comment "Random Number Generation"
|
||||
|
||||
config CRYPTO_PRNG
|
||||
tristate "Pseudo Random Number Generation for Cryptographic modules"
|
||||
help
|
||||
This option enables the generic pseudo random number generator
|
||||
for cryptographic modules. Uses the Algorithm specified in
|
||||
ANSI X9.31 A.2.4
|
||||
|
||||
source "drivers/crypto/Kconfig"
|
||||
|
||||
endif # if CRYPTO
|
||||
|
|
|
|||
|
|
@ -69,7 +69,7 @@ obj-$(CONFIG_CRYPTO_MICHAEL_MIC) += michael_mic.o
|
|||
obj-$(CONFIG_CRYPTO_CRC32C) += crc32c.o
|
||||
obj-$(CONFIG_CRYPTO_AUTHENC) += authenc.o
|
||||
obj-$(CONFIG_CRYPTO_LZO) += lzo.o
|
||||
obj-$(CONFIG_CRYPTO_PRNG) += prng.o
|
||||
|
||||
obj-$(CONFIG_CRYPTO_TEST) += tcrypt.o
|
||||
|
||||
#
|
||||
|
|
|
|||
410
crypto/prng.c
410
crypto/prng.c
|
|
@ -1,410 +0,0 @@
|
|||
/*
|
||||
* PRNG: Pseudo Random Number Generator
|
||||
* Based on NIST Recommended PRNG From ANSI X9.31 Appendix A.2.4 using
|
||||
* AES 128 cipher in RFC3686 ctr mode
|
||||
*
|
||||
* (C) Neil Horman <nhorman@tuxdriver.com>
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify it
|
||||
* under the terms of the GNU General Public License as published by the
|
||||
* Free Software Foundation; either version 2 of the License, or (at your
|
||||
* any later version.
|
||||
*
|
||||
*
|
||||
*/
|
||||
|
||||
#include <linux/err.h>
|
||||
#include <linux/init.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/mm.h>
|
||||
#include <linux/slab.h>
|
||||
#include <linux/fs.h>
|
||||
#include <linux/scatterlist.h>
|
||||
#include <linux/string.h>
|
||||
#include <linux/crypto.h>
|
||||
#include <linux/highmem.h>
|
||||
#include <linux/moduleparam.h>
|
||||
#include <linux/jiffies.h>
|
||||
#include <linux/timex.h>
|
||||
#include <linux/interrupt.h>
|
||||
#include <linux/miscdevice.h>
|
||||
#include "prng.h"
|
||||
|
||||
#define TEST_PRNG_ON_START 0
|
||||
|
||||
#define DEFAULT_PRNG_KEY "0123456789abcdef1011"
|
||||
#define DEFAULT_PRNG_KSZ 20
|
||||
#define DEFAULT_PRNG_IV "defaultv"
|
||||
#define DEFAULT_PRNG_IVSZ 8
|
||||
#define DEFAULT_BLK_SZ 16
|
||||
#define DEFAULT_V_SEED "zaybxcwdveuftgsh"
|
||||
|
||||
/*
|
||||
* Flags for the prng_context flags field
|
||||
*/
|
||||
|
||||
#define PRNG_FIXED_SIZE 0x1
|
||||
#define PRNG_NEED_RESET 0x2
|
||||
|
||||
/*
|
||||
* Note: DT is our counter value
|
||||
* I is our intermediate value
|
||||
* V is our seed vector
|
||||
* See http://csrc.nist.gov/groups/STM/cavp/documents/rng/931rngext.pdf
|
||||
* for implementation details
|
||||
*/
|
||||
|
||||
|
||||
struct prng_context {
|
||||
char *prng_key;
|
||||
char *prng_iv;
|
||||
spinlock_t prng_lock;
|
||||
unsigned char rand_data[DEFAULT_BLK_SZ];
|
||||
unsigned char last_rand_data[DEFAULT_BLK_SZ];
|
||||
unsigned char DT[DEFAULT_BLK_SZ];
|
||||
unsigned char I[DEFAULT_BLK_SZ];
|
||||
unsigned char V[DEFAULT_BLK_SZ];
|
||||
u32 rand_data_valid;
|
||||
struct crypto_blkcipher *tfm;
|
||||
u32 flags;
|
||||
};
|
||||
|
||||
static int dbg;
|
||||
|
||||
static void hexdump(char *note, unsigned char *buf, unsigned int len)
|
||||
{
|
||||
if (dbg) {
|
||||
printk(KERN_CRIT "%s", note);
|
||||
print_hex_dump(KERN_CONT, "", DUMP_PREFIX_OFFSET,
|
||||
16, 1,
|
||||
buf, len, false);
|
||||
}
|
||||
}
|
||||
|
||||
#define dbgprint(format, args...) do {if(dbg) printk(format, ##args);} while(0)
|
||||
|
||||
static void xor_vectors(unsigned char *in1, unsigned char *in2,
|
||||
unsigned char *out, unsigned int size)
|
||||
{
|
||||
int i;
|
||||
|
||||
for (i=0;i<size;i++)
|
||||
out[i] = in1[i] ^ in2[i];
|
||||
|
||||
}
|
||||
/*
|
||||
* Returns DEFAULT_BLK_SZ bytes of random data per call
|
||||
* returns 0 if generation succeded, <0 if something went wrong
|
||||
*/
|
||||
static int _get_more_prng_bytes(struct prng_context *ctx)
|
||||
{
|
||||
int i;
|
||||
struct blkcipher_desc desc;
|
||||
struct scatterlist sg_in, sg_out;
|
||||
int ret;
|
||||
unsigned char tmp[DEFAULT_BLK_SZ];
|
||||
|
||||
desc.tfm = ctx->tfm;
|
||||
desc.flags = 0;
|
||||
|
||||
|
||||
dbgprint(KERN_CRIT "Calling _get_more_prng_bytes for context %p\n",ctx);
|
||||
|
||||
hexdump("Input DT: ", ctx->DT, DEFAULT_BLK_SZ);
|
||||
hexdump("Input I: ", ctx->I, DEFAULT_BLK_SZ);
|
||||
hexdump("Input V: ", ctx->V, DEFAULT_BLK_SZ);
|
||||
|
||||
/*
|
||||
* This algorithm is a 3 stage state machine
|
||||
*/
|
||||
for (i=0;i<3;i++) {
|
||||
|
||||
desc.tfm = ctx->tfm;
|
||||
desc.flags = 0;
|
||||
switch (i) {
|
||||
case 0:
|
||||
/*
|
||||
* Start by encrypting the counter value
|
||||
* This gives us an intermediate value I
|
||||
*/
|
||||
memcpy(tmp, ctx->DT, DEFAULT_BLK_SZ);
|
||||
sg_init_one(&sg_out, &ctx->I[0], DEFAULT_BLK_SZ);
|
||||
hexdump("tmp stage 0: ", tmp, DEFAULT_BLK_SZ);
|
||||
break;
|
||||
case 1:
|
||||
|
||||
/*
|
||||
* Next xor I with our secret vector V
|
||||
* encrypt that result to obtain our
|
||||
* pseudo random data which we output
|
||||
*/
|
||||
xor_vectors(ctx->I, ctx->V, tmp, DEFAULT_BLK_SZ);
|
||||
sg_init_one(&sg_out, &ctx->rand_data[0], DEFAULT_BLK_SZ);
|
||||
hexdump("tmp stage 1: ", tmp, DEFAULT_BLK_SZ);
|
||||
break;
|
||||
case 2:
|
||||
/*
|
||||
* First check that we didn't produce the same random data
|
||||
* that we did last time around through this
|
||||
*/
|
||||
if (!memcmp(ctx->rand_data, ctx->last_rand_data, DEFAULT_BLK_SZ)) {
|
||||
printk(KERN_ERR "ctx %p Failed repetition check!\n",
|
||||
ctx);
|
||||
ctx->flags |= PRNG_NEED_RESET;
|
||||
return -1;
|
||||
}
|
||||
memcpy(ctx->last_rand_data, ctx->rand_data, DEFAULT_BLK_SZ);
|
||||
|
||||
/*
|
||||
* Lastly xor the random data with I
|
||||
* and encrypt that to obtain a new secret vector V
|
||||
*/
|
||||
xor_vectors(ctx->rand_data, ctx->I, tmp, DEFAULT_BLK_SZ);
|
||||
sg_init_one(&sg_out, &ctx->V[0], DEFAULT_BLK_SZ);
|
||||
hexdump("tmp stage 2: ", tmp, DEFAULT_BLK_SZ);
|
||||
break;
|
||||
}
|
||||
|
||||
/* Initialize our input buffer */
|
||||
sg_init_one(&sg_in, &tmp[0], DEFAULT_BLK_SZ);
|
||||
|
||||
/* do the encryption */
|
||||
ret = crypto_blkcipher_encrypt(&desc, &sg_out, &sg_in, DEFAULT_BLK_SZ);
|
||||
|
||||
/* And check the result */
|
||||
if (ret) {
|
||||
dbgprint(KERN_CRIT "Encryption of new block failed for context %p\n",ctx);
|
||||
ctx->rand_data_valid = DEFAULT_BLK_SZ;
|
||||
return -1;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/*
|
||||
* Now update our DT value
|
||||
*/
|
||||
for (i=DEFAULT_BLK_SZ-1;i>0;i--) {
|
||||
ctx->DT[i] = ctx->DT[i-1];
|
||||
}
|
||||
ctx->DT[0] += 1;
|
||||
|
||||
dbgprint("Returning new block for context %p\n",ctx);
|
||||
ctx->rand_data_valid = 0;
|
||||
|
||||
hexdump("Output DT: ", ctx->DT, DEFAULT_BLK_SZ);
|
||||
hexdump("Output I: ", ctx->I, DEFAULT_BLK_SZ);
|
||||
hexdump("Output V: ", ctx->V, DEFAULT_BLK_SZ);
|
||||
hexdump("New Random Data: ", ctx->rand_data, DEFAULT_BLK_SZ);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Our exported functions */
|
||||
int get_prng_bytes(char *buf, int nbytes, struct prng_context *ctx)
|
||||
{
|
||||
unsigned long flags;
|
||||
unsigned char *ptr = buf;
|
||||
unsigned int byte_count = (unsigned int)nbytes;
|
||||
int err;
|
||||
|
||||
|
||||
if (nbytes < 0)
|
||||
return -EINVAL;
|
||||
|
||||
spin_lock_irqsave(&ctx->prng_lock, flags);
|
||||
|
||||
err = -EFAULT;
|
||||
if (ctx->flags & PRNG_NEED_RESET)
|
||||
goto done;
|
||||
|
||||
/*
|
||||
* If the FIXED_SIZE flag is on, only return whole blocks of
|
||||
* pseudo random data
|
||||
*/
|
||||
err = -EINVAL;
|
||||
if (ctx->flags & PRNG_FIXED_SIZE) {
|
||||
if (nbytes < DEFAULT_BLK_SZ)
|
||||
goto done;
|
||||
byte_count = DEFAULT_BLK_SZ;
|
||||
}
|
||||
|
||||
err = byte_count;
|
||||
|
||||
dbgprint(KERN_CRIT "getting %d random bytes for context %p\n",byte_count, ctx);
|
||||
|
||||
|
||||
remainder:
|
||||
if (ctx->rand_data_valid == DEFAULT_BLK_SZ) {
|
||||
if (_get_more_prng_bytes(ctx) < 0) {
|
||||
memset(buf, 0, nbytes);
|
||||
err = -EFAULT;
|
||||
goto done;
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Copy up to the next whole block size
|
||||
*/
|
||||
if (byte_count < DEFAULT_BLK_SZ) {
|
||||
for (;ctx->rand_data_valid < DEFAULT_BLK_SZ; ctx->rand_data_valid++) {
|
||||
*ptr = ctx->rand_data[ctx->rand_data_valid];
|
||||
ptr++;
|
||||
byte_count--;
|
||||
if (byte_count == 0)
|
||||
goto done;
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Now copy whole blocks
|
||||
*/
|
||||
for(;byte_count >= DEFAULT_BLK_SZ; byte_count -= DEFAULT_BLK_SZ) {
|
||||
if (_get_more_prng_bytes(ctx) < 0) {
|
||||
memset(buf, 0, nbytes);
|
||||
err = -1;
|
||||
goto done;
|
||||
}
|
||||
memcpy(ptr, ctx->rand_data, DEFAULT_BLK_SZ);
|
||||
ctx->rand_data_valid += DEFAULT_BLK_SZ;
|
||||
ptr += DEFAULT_BLK_SZ;
|
||||
}
|
||||
|
||||
/*
|
||||
* Now copy any extra partial data
|
||||
*/
|
||||
if (byte_count)
|
||||
goto remainder;
|
||||
|
||||
done:
|
||||
spin_unlock_irqrestore(&ctx->prng_lock, flags);
|
||||
dbgprint(KERN_CRIT "returning %d from get_prng_bytes in context %p\n",err, ctx);
|
||||
return err;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(get_prng_bytes);
|
||||
|
||||
struct prng_context *alloc_prng_context(void)
|
||||
{
|
||||
struct prng_context *ctx=kzalloc(sizeof(struct prng_context), GFP_KERNEL);
|
||||
|
||||
spin_lock_init(&ctx->prng_lock);
|
||||
|
||||
if (reset_prng_context(ctx, NULL, NULL, NULL, NULL)) {
|
||||
kfree(ctx);
|
||||
ctx = NULL;
|
||||
}
|
||||
|
||||
dbgprint(KERN_CRIT "returning context %p\n",ctx);
|
||||
return ctx;
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL_GPL(alloc_prng_context);
|
||||
|
||||
void free_prng_context(struct prng_context *ctx)
|
||||
{
|
||||
crypto_free_blkcipher(ctx->tfm);
|
||||
kfree(ctx);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(free_prng_context);
|
||||
|
||||
int reset_prng_context(struct prng_context *ctx,
|
||||
unsigned char *key, unsigned char *iv,
|
||||
unsigned char *V, unsigned char *DT)
|
||||
{
|
||||
int ret;
|
||||
int iv_len;
|
||||
int rc = -EFAULT;
|
||||
|
||||
spin_lock(&ctx->prng_lock);
|
||||
ctx->flags |= PRNG_NEED_RESET;
|
||||
|
||||
if (key)
|
||||
memcpy(ctx->prng_key,key,strlen(ctx->prng_key));
|
||||
else
|
||||
ctx->prng_key = DEFAULT_PRNG_KEY;
|
||||
|
||||
if (iv)
|
||||
memcpy(ctx->prng_iv,iv, strlen(ctx->prng_iv));
|
||||
else
|
||||
ctx->prng_iv = DEFAULT_PRNG_IV;
|
||||
|
||||
if (V)
|
||||
memcpy(ctx->V,V,DEFAULT_BLK_SZ);
|
||||
else
|
||||
memcpy(ctx->V,DEFAULT_V_SEED,DEFAULT_BLK_SZ);
|
||||
|
||||
if (DT)
|
||||
memcpy(ctx->DT, DT, DEFAULT_BLK_SZ);
|
||||
else
|
||||
memset(ctx->DT, 0, DEFAULT_BLK_SZ);
|
||||
|
||||
memset(ctx->rand_data,0,DEFAULT_BLK_SZ);
|
||||
memset(ctx->last_rand_data,0,DEFAULT_BLK_SZ);
|
||||
|
||||
if (ctx->tfm)
|
||||
crypto_free_blkcipher(ctx->tfm);
|
||||
|
||||
ctx->tfm = crypto_alloc_blkcipher("rfc3686(ctr(aes))",0,0);
|
||||
if (!ctx->tfm) {
|
||||
dbgprint(KERN_CRIT "Failed to alloc crypto tfm for context %p\n",ctx->tfm);
|
||||
goto out;
|
||||
}
|
||||
|
||||
ctx->rand_data_valid = DEFAULT_BLK_SZ;
|
||||
|
||||
ret = crypto_blkcipher_setkey(ctx->tfm, ctx->prng_key, strlen(ctx->prng_key));
|
||||
if (ret) {
|
||||
dbgprint(KERN_CRIT "PRNG: setkey() failed flags=%x\n",
|
||||
crypto_blkcipher_get_flags(ctx->tfm));
|
||||
crypto_free_blkcipher(ctx->tfm);
|
||||
goto out;
|
||||
}
|
||||
|
||||
iv_len = crypto_blkcipher_ivsize(ctx->tfm);
|
||||
if (iv_len) {
|
||||
crypto_blkcipher_set_iv(ctx->tfm, ctx->prng_iv, iv_len);
|
||||
}
|
||||
rc = 0;
|
||||
ctx->flags &= ~PRNG_NEED_RESET;
|
||||
out:
|
||||
spin_unlock(&ctx->prng_lock);
|
||||
|
||||
return rc;
|
||||
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(reset_prng_context);
|
||||
|
||||
/* Module initalization */
|
||||
static int __init prng_mod_init(void)
|
||||
{
|
||||
|
||||
#ifdef TEST_PRNG_ON_START
|
||||
int i;
|
||||
unsigned char tmpbuf[DEFAULT_BLK_SZ];
|
||||
|
||||
struct prng_context *ctx = alloc_prng_context();
|
||||
if (ctx == NULL)
|
||||
return -EFAULT;
|
||||
for (i=0;i<16;i++) {
|
||||
if (get_prng_bytes(tmpbuf, DEFAULT_BLK_SZ, ctx) < 0) {
|
||||
free_prng_context(ctx);
|
||||
return -EFAULT;
|
||||
}
|
||||
}
|
||||
free_prng_context(ctx);
|
||||
#endif
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void __exit prng_mod_fini(void)
|
||||
{
|
||||
return;
|
||||
}
|
||||
|
||||
MODULE_LICENSE("GPL");
|
||||
MODULE_DESCRIPTION("Software Pseudo Random Number Generator");
|
||||
MODULE_AUTHOR("Neil Horman <nhorman@tuxdriver.com>");
|
||||
module_param(dbg, int, 0);
|
||||
MODULE_PARM_DESC(dbg, "Boolean to enable debugging (0/1 == off/on)");
|
||||
module_init(prng_mod_init);
|
||||
module_exit(prng_mod_fini);
|
||||
|
|
@ -1,27 +0,0 @@
|
|||
/*
|
||||
* PRNG: Pseudo Random Number Generator
|
||||
*
|
||||
* (C) Neil Horman <nhorman@tuxdriver.com>
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify it
|
||||
* under the terms of the GNU General Public License as published by the
|
||||
* Free Software Foundation; either version 2 of the License, or (at your
|
||||
* any later version.
|
||||
*
|
||||
*
|
||||
*/
|
||||
|
||||
#ifndef _PRNG_H_
|
||||
#define _PRNG_H_
|
||||
struct prng_context;
|
||||
|
||||
int get_prng_bytes(char *buf, int nbytes, struct prng_context *ctx);
|
||||
struct prng_context *alloc_prng_context(void);
|
||||
int reset_prng_context(struct prng_context *ctx,
|
||||
unsigned char *key, unsigned char *iv,
|
||||
unsigned char *V,
|
||||
unsigned char *DT);
|
||||
void free_prng_context(struct prng_context *ctx);
|
||||
|
||||
#endif
|
||||
|
||||
Loading…
Reference in New Issue
Block a user