[CRYPTO] padlock: Convert padlock-sha to use crypto_hash

This patch converts padlock-sha to use crypto_hash for its fallback.
It also changes the fallback selection to use selection by type instead
of name.  This is done through the new CRYPTO_ALG_NEED_FALLBACK bit,
which is set if and only if an algorithm needs a fallback of the same
type.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Herbert Xu 2006-08-26 18:34:10 +10:00
parent e4d5b79c66
commit 6010439f47
2 changed files with 40 additions and 55 deletions

View File

@ -12,10 +12,11 @@
*
*/
#include <crypto/algapi.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/crypto.h>
#include <linux/cryptohash.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
@ -30,28 +31,17 @@
#define SHA256_DIGEST_SIZE 32
#define SHA256_HMAC_BLOCK_SIZE 64
static char *sha1_fallback = SHA1_DEFAULT_FALLBACK;
static char *sha256_fallback = SHA256_DEFAULT_FALLBACK;
module_param(sha1_fallback, charp, 0644);
module_param(sha256_fallback, charp, 0644);
MODULE_PARM_DESC(sha1_fallback, "Fallback driver for SHA1. Default is "
SHA1_DEFAULT_FALLBACK);
MODULE_PARM_DESC(sha256_fallback, "Fallback driver for SHA256. Default is "
SHA256_DEFAULT_FALLBACK);
struct padlock_sha_ctx {
char *data;
size_t used;
int bypass;
void (*f_sha_padlock)(const char *in, char *out, int count);
struct crypto_tfm *fallback_tfm;
struct hash_desc fallback;
};
static inline struct padlock_sha_ctx *ctx(struct crypto_tfm *tfm)
{
return (struct padlock_sha_ctx *)(crypto_tfm_ctx(tfm));
return crypto_tfm_ctx(tfm);
}
/* We'll need aligned address on the stack */
@ -65,14 +55,12 @@ static void padlock_sha_bypass(struct crypto_tfm *tfm)
if (ctx(tfm)->bypass)
return;
BUG_ON(!ctx(tfm)->fallback_tfm);
crypto_digest_init(ctx(tfm)->fallback_tfm);
crypto_hash_init(&ctx(tfm)->fallback);
if (ctx(tfm)->data && ctx(tfm)->used) {
struct scatterlist sg;
sg_set_buf(&sg, ctx(tfm)->data, ctx(tfm)->used);
crypto_digest_update(ctx(tfm)->fallback_tfm, &sg, 1);
crypto_hash_update(&ctx(tfm)->fallback, &sg, sg.length);
}
ctx(tfm)->used = 0;
@ -95,9 +83,8 @@ static void padlock_sha_update(struct crypto_tfm *tfm,
if (unlikely(ctx(tfm)->bypass)) {
struct scatterlist sg;
BUG_ON(!ctx(tfm)->fallback_tfm);
sg_set_buf(&sg, (uint8_t *)data, length);
crypto_digest_update(ctx(tfm)->fallback_tfm, &sg, 1);
crypto_hash_update(&ctx(tfm)->fallback, &sg, length);
return;
}
@ -160,8 +147,7 @@ static void padlock_do_sha256(const char *in, char *out, int count)
static void padlock_sha_final(struct crypto_tfm *tfm, uint8_t *out)
{
if (unlikely(ctx(tfm)->bypass)) {
BUG_ON(!ctx(tfm)->fallback_tfm);
crypto_digest_final(ctx(tfm)->fallback_tfm, out);
crypto_hash_final(&ctx(tfm)->fallback, out);
ctx(tfm)->bypass = 0;
return;
}
@ -172,8 +158,11 @@ static void padlock_sha_final(struct crypto_tfm *tfm, uint8_t *out)
ctx(tfm)->used = 0;
}
static int padlock_cra_init(struct crypto_tfm *tfm, const char *fallback_driver_name)
static int padlock_cra_init(struct crypto_tfm *tfm)
{
const char *fallback_driver_name = tfm->__crt_alg->cra_name;
struct crypto_hash *fallback_tfm;
/* For now we'll allocate one page. This
* could eventually be configurable one day. */
ctx(tfm)->data = (char *)__get_free_page(GFP_KERNEL);
@ -181,14 +170,17 @@ static int padlock_cra_init(struct crypto_tfm *tfm, const char *fallback_driver_
return -ENOMEM;
/* Allocate a fallback and abort if it failed. */
ctx(tfm)->fallback_tfm = crypto_alloc_tfm(fallback_driver_name, 0);
if (!ctx(tfm)->fallback_tfm) {
fallback_tfm = crypto_alloc_hash(fallback_driver_name, 0,
CRYPTO_ALG_ASYNC |
CRYPTO_ALG_NEED_FALLBACK);
if (IS_ERR(fallback_tfm)) {
printk(KERN_WARNING PFX "Fallback driver '%s' could not be loaded!\n",
fallback_driver_name);
free_page((unsigned long)(ctx(tfm)->data));
return -ENOENT;
return PTR_ERR(fallback_tfm);
}
ctx(tfm)->fallback.tfm = fallback_tfm;
return 0;
}
@ -196,14 +188,14 @@ static int padlock_sha1_cra_init(struct crypto_tfm *tfm)
{
ctx(tfm)->f_sha_padlock = padlock_do_sha1;
return padlock_cra_init(tfm, sha1_fallback);
return padlock_cra_init(tfm);
}
static int padlock_sha256_cra_init(struct crypto_tfm *tfm)
{
ctx(tfm)->f_sha_padlock = padlock_do_sha256;
return padlock_cra_init(tfm, sha256_fallback);
return padlock_cra_init(tfm);
}
static void padlock_cra_exit(struct crypto_tfm *tfm)
@ -213,16 +205,16 @@ static void padlock_cra_exit(struct crypto_tfm *tfm)
ctx(tfm)->data = NULL;
}
BUG_ON(!ctx(tfm)->fallback_tfm);
crypto_free_tfm(ctx(tfm)->fallback_tfm);
ctx(tfm)->fallback_tfm = NULL;
crypto_free_hash(ctx(tfm)->fallback.tfm);
ctx(tfm)->fallback.tfm = NULL;
}
static struct crypto_alg sha1_alg = {
.cra_name = "sha1",
.cra_driver_name = "sha1-padlock",
.cra_priority = PADLOCK_CRA_PRIORITY,
.cra_flags = CRYPTO_ALG_TYPE_DIGEST,
.cra_flags = CRYPTO_ALG_TYPE_DIGEST |
CRYPTO_ALG_NEED_FALLBACK,
.cra_blocksize = SHA1_HMAC_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct padlock_sha_ctx),
.cra_module = THIS_MODULE,
@ -243,7 +235,8 @@ static struct crypto_alg sha256_alg = {
.cra_name = "sha256",
.cra_driver_name = "sha256-padlock",
.cra_priority = PADLOCK_CRA_PRIORITY,
.cra_flags = CRYPTO_ALG_TYPE_DIGEST,
.cra_flags = CRYPTO_ALG_TYPE_DIGEST |
CRYPTO_ALG_NEED_FALLBACK,
.cra_blocksize = SHA256_HMAC_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct padlock_sha_ctx),
.cra_module = THIS_MODULE,
@ -262,29 +255,15 @@ static struct crypto_alg sha256_alg = {
static void __init padlock_sha_check_fallbacks(void)
{
struct crypto_tfm *tfm;
if (!crypto_has_hash("sha1", 0, CRYPTO_ALG_ASYNC |
CRYPTO_ALG_NEED_FALLBACK))
printk(KERN_WARNING PFX
"Couldn't load fallback module for sha1.\n");
/* We'll try to allocate one TFM for each fallback
* to test that the modules are available. */
tfm = crypto_alloc_tfm(sha1_fallback, 0);
if (!tfm) {
printk(KERN_WARNING PFX "Couldn't load fallback module for '%s'. Tried '%s'.\n",
sha1_alg.cra_name, sha1_fallback);
} else {
printk(KERN_NOTICE PFX "Fallback for '%s' is driver '%s' (prio=%d)\n", sha1_alg.cra_name,
crypto_tfm_alg_driver_name(tfm), crypto_tfm_alg_priority(tfm));
crypto_free_tfm(tfm);
}
tfm = crypto_alloc_tfm(sha256_fallback, 0);
if (!tfm) {
printk(KERN_WARNING PFX "Couldn't load fallback module for '%s'. Tried '%s'.\n",
sha256_alg.cra_name, sha256_fallback);
} else {
printk(KERN_NOTICE PFX "Fallback for '%s' is driver '%s' (prio=%d)\n", sha256_alg.cra_name,
crypto_tfm_alg_driver_name(tfm), crypto_tfm_alg_priority(tfm));
crypto_free_tfm(tfm);
}
if (!crypto_has_hash("sha256", 0, CRYPTO_ALG_ASYNC |
CRYPTO_ALG_NEED_FALLBACK))
printk(KERN_WARNING PFX
"Couldn't load fallback module for sha256.\n");
}
static int __init padlock_init(void)

View File

@ -42,6 +42,12 @@
#define CRYPTO_ALG_DYING 0x00000040
#define CRYPTO_ALG_ASYNC 0x00000080
/*
* Set this bit if and only if the algorithm requires another algorithm of
* the same type to handle corner cases.
*/
#define CRYPTO_ALG_NEED_FALLBACK 0x00000100
/*
* Transform masks and values (for crt_flags).
*/