Re: [PATCH] crypto: obscure state information on free
From: Herbert Xu <herbert@gondor.apana.org.au>
Date: 2008-08-17 12:24:10
Also in:
lkml
Subsystem:
crypto api, the rest · Maintainers:
Herbert Xu, "David S. Miller", Linus Torvalds
On Sun, Aug 17, 2008 at 10:20:47PM +1000, Herbert Xu wrote:
There is also a new global rng object for everyone to use rather than having it allocated by every user separately.
And here is the new IV generator patch to use the global RNG object.
commit 1da64c8d0d573dcb1b67c42d41c0adf511f81dfc
Author: Herbert Xu [off-list ref]
Date: Thu Aug 14 22:21:31 2008 +1000
crypto: skcipher - Use RNG interface instead of get_random_bytes
This patch makes the IV generators use the new RNG interface so
that the user can pick an RNG other than the default get_random_bytes.
Signed-off-by: Herbert Xu [off-list ref]
diff --git a/crypto/Kconfig b/crypto/Kconfig
index b00860f..a985065 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig@@ -33,6 +33,7 @@ config CRYPTO_AEAD config CRYPTO_BLKCIPHER tristate select CRYPTO_ALGAPI + select CRYPTO_RNG config CRYPTO_HASH tristate
@@ -117,6 +118,7 @@ config CRYPTO_SEQIV tristate "Sequence Number IV Generator" select CRYPTO_AEAD select CRYPTO_BLKCIPHER + select CRYPTO_RNG help This IV generator generates an IV based on a sequence number by xoring it with a salt. This algorithm is mainly useful for CTR
diff --git a/crypto/chainiv.c b/crypto/chainiv.c
index cf68d43..7c37a49 100644
--- a/crypto/chainiv.c
+++ b/crypto/chainiv.c@@ -14,11 +14,11 @@ */ #include <crypto/internal/skcipher.h> +#include <crypto/rng.h> #include <linux/err.h> #include <linux/init.h> #include <linux/kernel.h> #include <linux/module.h> -#include <linux/random.h> #include <linux/spinlock.h> #include <linux/string.h> #include <linux/workqueue.h>
@@ -83,6 +83,7 @@ static int chainiv_givencrypt_first(struct skcipher_givcrypt_request *req) { struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req); struct chainiv_ctx *ctx = crypto_ablkcipher_ctx(geniv); + int err = 0; spin_lock_bh(&ctx->lock); if (crypto_ablkcipher_crt(geniv)->givencrypt !=
@@ -90,11 +91,15 @@ static int chainiv_givencrypt_first(struct skcipher_givcrypt_request *req) goto unlock; crypto_ablkcipher_crt(geniv)->givencrypt = chainiv_givencrypt; - get_random_bytes(ctx->iv, crypto_ablkcipher_ivsize(geniv)); + err = crypto_rng_get_bytes(crypto_default_rng, ctx->iv, + crypto_ablkcipher_ivsize(geniv)); unlock: spin_unlock_bh(&ctx->lock); + if (err) + return err; + return chainiv_givencrypt(req); }
@@ -203,6 +208,7 @@ static int async_chainiv_givencrypt_first(struct skcipher_givcrypt_request *req) { struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req); struct async_chainiv_ctx *ctx = crypto_ablkcipher_ctx(geniv); + int err = 0; if (test_and_set_bit(CHAINIV_STATE_INUSE, &ctx->state)) goto out;
@@ -212,11 +218,15 @@ static int async_chainiv_givencrypt_first(struct skcipher_givcrypt_request *req) goto unlock; crypto_ablkcipher_crt(geniv)->givencrypt = async_chainiv_givencrypt; - get_random_bytes(ctx->iv, crypto_ablkcipher_ivsize(geniv)); + err = crypto_rng_get_bytes(crypto_default_rng, ctx->iv, + crypto_ablkcipher_ivsize(geniv)); unlock: clear_bit(CHAINIV_STATE_INUSE, &ctx->state); + if (err) + return err; + out: return async_chainiv_givencrypt(req); }
@@ -284,9 +294,13 @@ static struct crypto_instance *chainiv_alloc(struct rtattr **tb) if (IS_ERR(algt)) return ERR_PTR(err); + err = crypto_get_default_rng(); + if (err) + return ERR_PTR(err); + inst = skcipher_geniv_alloc(&chainiv_tmpl, tb, 0, 0); if (IS_ERR(inst)) - goto out; + goto put_rng; inst->alg.cra_ablkcipher.givencrypt = chainiv_givencrypt_first;
@@ -311,12 +325,22 @@ static struct crypto_instance *chainiv_alloc(struct rtattr **tb) out: return inst; + +put_rng: + crypto_put_default_rng(); + goto out; +} + +static void chainiv_free(struct crypto_instance *inst) +{ + skcipher_geniv_free(inst); + crypto_put_default_rng(); } static struct crypto_template chainiv_tmpl = { .name = "chainiv", .alloc = chainiv_alloc, - .free = skcipher_geniv_free, + .free = chainiv_free, .module = THIS_MODULE, };
diff --git a/crypto/eseqiv.c b/crypto/eseqiv.c
index f5def21..2a342c8 100644
--- a/crypto/eseqiv.c
+++ b/crypto/eseqiv.c@@ -16,13 +16,13 @@ */ #include <crypto/internal/skcipher.h> +#include <crypto/rng.h> #include <crypto/scatterwalk.h> #include <linux/err.h> #include <linux/init.h> #include <linux/kernel.h> #include <linux/mm.h> #include <linux/module.h> -#include <linux/random.h> #include <linux/scatterlist.h> #include <linux/spinlock.h> #include <linux/string.h>
@@ -163,17 +163,22 @@ static int eseqiv_givencrypt_first(struct skcipher_givcrypt_request *req) { struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req); struct eseqiv_ctx *ctx = crypto_ablkcipher_ctx(geniv); + int err = 0; spin_lock_bh(&ctx->lock); if (crypto_ablkcipher_crt(geniv)->givencrypt != eseqiv_givencrypt_first) goto unlock; crypto_ablkcipher_crt(geniv)->givencrypt = eseqiv_givencrypt; - get_random_bytes(ctx->salt, crypto_ablkcipher_ivsize(geniv)); + err = crypto_rng_get_bytes(crypto_default_rng, ctx->salt, + crypto_ablkcipher_ivsize(geniv)); unlock: spin_unlock_bh(&ctx->lock); + if (err) + return err; + return eseqiv_givencrypt(req); }
@@ -216,9 +221,13 @@ static struct crypto_instance *eseqiv_alloc(struct rtattr **tb) struct crypto_instance *inst; int err; + err = crypto_get_default_rng(); + if (err) + return ERR_PTR(err); + inst = skcipher_geniv_alloc(&eseqiv_tmpl, tb, 0, 0); if (IS_ERR(inst)) - goto out; + goto put_rng; err = -EINVAL; if (inst->alg.cra_ablkcipher.ivsize != inst->alg.cra_blocksize)
@@ -238,13 +247,21 @@ out: free_inst: skcipher_geniv_free(inst); inst = ERR_PTR(err); +put_rng: + crypto_put_default_rng(); goto out; } +static void eseqiv_free(struct crypto_instance *inst) +{ + skcipher_geniv_free(inst); + crypto_put_default_rng(); +} + static struct crypto_template eseqiv_tmpl = { .name = "eseqiv", .alloc = eseqiv_alloc, - .free = skcipher_geniv_free, + .free = eseqiv_free, .module = THIS_MODULE, };
diff --git a/crypto/seqiv.c b/crypto/seqiv.c
index b903aab..5a013a8 100644
--- a/crypto/seqiv.c
+++ b/crypto/seqiv.c@@ -15,11 +15,11 @@ #include <crypto/internal/aead.h> #include <crypto/internal/skcipher.h> +#include <crypto/rng.h> #include <linux/err.h> #include <linux/init.h> #include <linux/kernel.h> #include <linux/module.h> -#include <linux/random.h> #include <linux/spinlock.h> #include <linux/string.h>
@@ -189,17 +189,22 @@ static int seqiv_givencrypt_first(struct skcipher_givcrypt_request *req) { struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req); struct seqiv_ctx *ctx = crypto_ablkcipher_ctx(geniv); + int err = 0; spin_lock_bh(&ctx->lock); if (crypto_ablkcipher_crt(geniv)->givencrypt != seqiv_givencrypt_first) goto unlock; crypto_ablkcipher_crt(geniv)->givencrypt = seqiv_givencrypt; - get_random_bytes(ctx->salt, crypto_ablkcipher_ivsize(geniv)); + err = crypto_rng_get_bytes(crypto_default_rng, ctx->salt, + crypto_ablkcipher_ivsize(geniv)); unlock: spin_unlock_bh(&ctx->lock); + if (err) + return err; + return seqiv_givencrypt(req); }
@@ -207,17 +212,22 @@ static int seqiv_aead_givencrypt_first(struct aead_givcrypt_request *req) { struct crypto_aead *geniv = aead_givcrypt_reqtfm(req); struct seqiv_ctx *ctx = crypto_aead_ctx(geniv); + int err = 0; spin_lock_bh(&ctx->lock); if (crypto_aead_crt(geniv)->givencrypt != seqiv_aead_givencrypt_first) goto unlock; crypto_aead_crt(geniv)->givencrypt = seqiv_aead_givencrypt; - get_random_bytes(ctx->salt, crypto_aead_ivsize(geniv)); + err = crypto_rng_get_bytes(crypto_default_rng, ctx->salt, + crypto_aead_ivsize(geniv)); unlock: spin_unlock_bh(&ctx->lock); + if (err) + return err; + return seqiv_aead_givencrypt(req); }
@@ -298,19 +308,27 @@ static struct crypto_instance *seqiv_alloc(struct rtattr **tb) if (IS_ERR(algt)) return ERR_PTR(err); + err = crypto_get_default_rng(); + if (err) + return ERR_PTR(err); + if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & CRYPTO_ALG_TYPE_MASK) inst = seqiv_ablkcipher_alloc(tb); else inst = seqiv_aead_alloc(tb); if (IS_ERR(inst)) - goto out; + goto put_rng; inst->alg.cra_alignmask |= __alignof__(u32) - 1; inst->alg.cra_ctxsize += sizeof(struct seqiv_ctx); out: return inst; + +put_rng: + crypto_put_default_rng(); + goto out; } static void seqiv_free(struct crypto_instance *inst)
@@ -319,6 +337,7 @@ static void seqiv_free(struct crypto_instance *inst) skcipher_geniv_free(inst); else aead_geniv_free(inst); + crypto_put_default_rng(); } static struct crypto_template seqiv_tmpl = {
Cheers, -- Visit Openswan at http://www.openswan.org/ Email: Herbert Xu ~{PmV>HI~} [off-list ref] Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt