crypto: drbg - use aligned buffers

Hardware cipher implementation may require aligned buffers. All buffers
that potentially are processed with a cipher are now aligned.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/crypto/drbg.c b/crypto/drbg.c
index 4ee1a9c..8ac3ea1 100644 (file)
--- a/crypto/drbg.c
+++ b/crypto/drbg.c
@@ -1139,11 +1139,11 @@ static inline void drbg_dealloc_state(struct drbg_state *drbg)
        if (!drbg)
                return;
        kzfree(drbg->V);
-       drbg->V = NULL;
+       drbg->Vbuf = NULL;
        kzfree(drbg->C);
-       drbg->C = NULL;
-       kzfree(drbg->scratchpad);
-       drbg->scratchpad = NULL;
+       drbg->Cbuf = NULL;
+       kzfree(drbg->scratchpadbuf);
+       drbg->scratchpadbuf = NULL;
        drbg->reseed_ctr = 0;
        drbg->d_ops = NULL;
        drbg->core = NULL;
@@ -1179,12 +1179,18 @@ static inline int drbg_alloc_state(struct drbg_state *drbg)
                goto err;
        }
 
-       drbg->V = kmalloc(drbg_statelen(drbg), GFP_KERNEL);
-       if (!drbg->V)
-               goto err;
-       drbg->C = kmalloc(drbg_statelen(drbg), GFP_KERNEL);
-       if (!drbg->C)
+       ret = drbg->d_ops->crypto_init(drbg);
+       if (ret < 0)
                goto err;
+
+       drbg->Vbuf = kmalloc(drbg_statelen(drbg) + ret, GFP_KERNEL);
+       if (!drbg->Vbuf)
+               goto fini;
+       drbg->V = PTR_ALIGN(drbg->Vbuf, ret + 1);
+       drbg->Cbuf = kmalloc(drbg_statelen(drbg) + ret, GFP_KERNEL);
+       if (!drbg->Cbuf)
+               goto fini;
+       drbg->C = PTR_ALIGN(drbg->Cbuf, ret + 1);
        /* scratchpad is only generated for CTR and Hash */
        if (drbg->core->flags & DRBG_HMAC)
                sb_size = 0;
@@ -1198,13 +1204,16 @@ static inline int drbg_alloc_state(struct drbg_state *drbg)
                sb_size = drbg_statelen(drbg) + drbg_blocklen(drbg);
 
        if (0 < sb_size) {
-               drbg->scratchpad = kzalloc(sb_size, GFP_KERNEL);
-               if (!drbg->scratchpad)
-                       goto err;
+               drbg->scratchpadbuf = kzalloc(sb_size + ret, GFP_KERNEL);
+               if (!drbg->scratchpadbuf)
+                       goto fini;
+               drbg->scratchpad = PTR_ALIGN(drbg->scratchpadbuf, ret + 1);
        }
 
        return 0;
 
+fini:
+       drbg->d_ops->crypto_fini(drbg);
 err:
        drbg_dealloc_state(drbg);
        return ret;
@@ -1472,10 +1481,6 @@ static int drbg_instantiate(struct drbg_state *drbg, struct drbg_string *pers,
                if (ret)
                        goto unlock;
 
-               ret = -EFAULT;
-               if (drbg->d_ops->crypto_init(drbg))
-                       goto err;
-
                ret = drbg_prepare_hrng(drbg);
                if (ret)
                        goto free_everything;
@@ -1499,8 +1504,6 @@ static int drbg_instantiate(struct drbg_state *drbg, struct drbg_string *pers,
        mutex_unlock(&drbg->drbg_mutex);
        return ret;
 
-err:
-       drbg_dealloc_state(drbg);
 unlock:
        mutex_unlock(&drbg->drbg_mutex);
        return ret;
@@ -1585,7 +1588,8 @@ static int drbg_init_hash_kernel(struct drbg_state *drbg)
        sdesc->shash.tfm = tfm;
        sdesc->shash.flags = 0;
        drbg->priv_data = sdesc;
-       return 0;
+
+       return crypto_shash_alignmask(tfm);
 }
 
 static int drbg_fini_hash_kernel(struct drbg_state *drbg)
@@ -1705,7 +1709,7 @@ static int drbg_init_sym_kernel(struct drbg_state *drbg)
        drbg->ctr_null_value = (u8 *)PTR_ALIGN(drbg->ctr_null_value_buf,
                                               alignmask + 1);
 
-       return 0;
+       return alignmask;
 }
 
 static void drbg_kcapi_symsetkey(struct drbg_state *drbg,

diff --git a/include/crypto/drbg.h b/include/crypto/drbg.h
index b2fe15d..61580b1 100644 (file)
--- a/include/crypto/drbg.h
+++ b/include/crypto/drbg.h
@@ -108,13 +108,16 @@ struct drbg_test_data {
 struct drbg_state {
        struct mutex drbg_mutex;        /* lock around DRBG */
        unsigned char *V;       /* internal state 10.1.1.1 1a) */
+       unsigned char *Vbuf;
        /* hash: static value 10.1.1.1 1b) hmac / ctr: key */
        unsigned char *C;
+       unsigned char *Cbuf;
        /* Number of RNG requests since last reseed -- 10.1.1.1 1c) */
        size_t reseed_ctr;
        size_t reseed_threshold;
         /* some memory the DRBG can use for its operation */
        unsigned char *scratchpad;
+       unsigned char *scratchpadbuf;
        void *priv_data;        /* Cipher handle */
 
        struct crypto_skcipher *ctr_handle;     /* CTR mode cipher handle */