Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6

Pull crypto update from Herbert Xu:
 "Here is the crypto update for 4.2:

  API:

   - Convert RNG interface to new style.

   - New AEAD interface with one SG list for AD and plain/cipher text.
     All external AEAD users have been converted.

   - New asymmetric key interface (akcipher).

  Algorithms:

   - Chacha20, Poly1305 and RFC7539 support.

   - New RSA implementation.

   - Jitter RNG.

   - DRBG is now seeded with both /dev/random and Jitter RNG.  If kernel
     pool isn't ready then DRBG will be reseeded when it is.

   - DRBG is now the default crypto API RNG, replacing krng.

   - 842 compression (previously part of powerpc nx driver).

  Drivers:

   - Accelerated SHA-512 for arm64.

   - New Marvell CESA driver that supports DMA and more algorithms.

   - Updated powerpc nx 842 support.

   - Added support for SEC1 hardware to talitos"

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (292 commits)
  crypto: marvell/cesa - remove COMPILE_TEST dependency
  crypto: algif_aead - Temporarily disable all AEAD algorithms
  crypto: af_alg - Forbid the use internal algorithms
  crypto: echainiv - Only hold RNG during initialisation
  crypto: seqiv - Add compatibility support without RNG
  crypto: eseqiv - Offer normal cipher functionality without RNG
  crypto: chainiv - Offer normal cipher functionality without RNG
  crypto: user - Add CRYPTO_MSG_DELRNG
  crypto: user - Move cryptouser.h to uapi
  crypto: rng - Do not free default RNG when it becomes unused
  crypto: skcipher - Allow givencrypt to be NULL
  crypto: sahara - propagate the error on clk_disable_unprepare() failure
  crypto: rsa - fix invalid select for AKCIPHER
  crypto: picoxcell - Update to the current clk API
  crypto: nx - Check for bogus firmware properties
  crypto: marvell/cesa - add DT bindings documentation
  crypto: marvell/cesa - add support for Kirkwood and Dove SoCs
  crypto: marvell/cesa - add support for Orion SoCs
  crypto: marvell/cesa - add allhwsupport module parameter
  crypto: marvell/cesa - add support for all armada SoCs
  ...

2 files changed, 71 insertions, 22 deletions

diff --git a/lib/mpi/mpicoder.c b/lib/mpi/mpicoder.c
index 4cc6442..bc0a1da 100644
--- a/lib/mpi/mpicoder.c
+++ b/lib/mpi/mpicoder.c
@@ -128,28 +128,36 @@ leave:
 }
 EXPORT_SYMBOL_GPL(mpi_read_from_buffer);
 
-/****************
- * Return an allocated buffer with the MPI (msb first).
- * NBYTES receives the length of this buffer. Caller must free the
- * return string (This function does return a 0 byte buffer with NBYTES
- * set to zero if the value of A is zero. If sign is not NULL, it will
- * be set to the sign of the A.
+/**
+ * mpi_read_buffer() - read MPI to a bufer provided by user (msb first)
+ *
+ * @a:		a multi precision integer
+ * @buf:	bufer to which the output will be written to. Needs to be at
+ *		leaset mpi_get_size(a) long.
+ * @buf_len:	size of the buf.
+ * @nbytes:	receives the actual length of the data written.
+ * @sign:	if not NULL, it will be set to the sign of a.
+ *
+ * Return:	0 on success or error code in case of error
  */
-void *mpi_get_buffer(MPI a, unsigned *nbytes, int *sign)
+int mpi_read_buffer(MPI a, uint8_t *buf, unsigned buf_len, unsigned *nbytes,
+		    int *sign)
 {
-	uint8_t *p, *buffer;
+	uint8_t *p;
 	mpi_limb_t alimb;
+	unsigned int n = mpi_get_size(a);
 	int i;
-	unsigned int n;
+
+	if (buf_len < n || !buf)
+		return -EINVAL;
 
 	if (sign)
 		*sign = a->sign;
-	*nbytes = n = a->nlimbs * BYTES_PER_MPI_LIMB;
-	if (!n)
-		n++;		/* avoid zero length allocation */
-	p = buffer = kmalloc(n, GFP_KERNEL);
-	if (!p)
-		return NULL;
+
+	if (nbytes)
+		*nbytes = n;
+
+	p = buf;
 
 	for (i = a->nlimbs - 1; i >= 0; i--) {
 		alimb = a->d[i];
@@ -171,15 +179,56 @@ void *mpi_get_buffer(MPI a, unsigned *nbytes, int *sign)
 #error please implement for this limb size.
 #endif
 	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mpi_read_buffer);
+
+/*
+ * mpi_get_buffer() - Returns an allocated buffer with the MPI (msb first).
+ * Caller must free the return string.
+ * This function does return a 0 byte buffer with nbytes set to zero if the
+ * value of A is zero.
+ *
+ * @a:		a multi precision integer.
+ * @nbytes:	receives the length of this buffer.
+ * @sign:	if not NULL, it will be set to the sign of the a.
+ *
+ * Return:	Pointer to MPI buffer or NULL on error
+ */
+void *mpi_get_buffer(MPI a, unsigned *nbytes, int *sign)
+{
+	uint8_t *buf, *p;
+	unsigned int n;
+	int ret;
+
+	if (!nbytes)
+		return NULL;
+
+	n = mpi_get_size(a);
+
+	if (!n)
+		n++;
+
+	buf = kmalloc(n, GFP_KERNEL);
+
+	if (!buf)
+		return NULL;
+
+	ret = mpi_read_buffer(a, buf, n, nbytes, sign);
+
+	if (ret) {
+		kfree(buf);
+		return NULL;
+	}
 
 	/* this is sub-optimal but we need to do the shift operation
 	 * because the caller has to free the returned buffer */
-	for (p = buffer; !*p && *nbytes; p++, --*nbytes)
+	for (p = buf; !*p && *nbytes; p++, --*nbytes)
 		;
-	if (p != buffer)
-		memmove(buffer, p, *nbytes);
+	if (p != buf)
+		memmove(buf, p, *nbytes);
 
-	return buffer;
+	return buf;
 }
 EXPORT_SYMBOL_GPL(mpi_get_buffer);
 
diff --git a/lib/mpi/mpiutil.c b/lib/mpi/mpiutil.c
index bf076d2..314f4df 100644
--- a/lib/mpi/mpiutil.c
+++ b/lib/mpi/mpiutil.c
@@ -69,7 +69,7 @@ void mpi_free_limb_space(mpi_ptr_t a)
 	if (!a)
 		return;
 
-	kfree(a);
+	kzfree(a);
 }
 
 void mpi_assign_limb_space(MPI a, mpi_ptr_t ap, unsigned nlimbs)
@@ -95,7 +95,7 @@ int mpi_resize(MPI a, unsigned nlimbs)
 		if (!p)
 			return -ENOMEM;
 		memcpy(p, a->d, a->alloced * sizeof(mpi_limb_t));
-		kfree(a->d);
+		kzfree(a->d);
 		a->d = p;
 	} else {
 		a->d = kzalloc(nlimbs * sizeof(mpi_limb_t), GFP_KERNEL);
@@ -112,7 +112,7 @@ void mpi_free(MPI a)
 		return;
 
 	if (a->flags & 4)
-		kfree(a->d);
+		kzfree(a->d);
 	else
 		mpi_free_limb_space(a->d);