Merge branch 'feature/establish-an-upstream-relationship-with-ics-openvpn-codebase-#5381' into develop

1 files changed, 70 insertions, 0 deletions

diff --git a/app/openssl/crypto/bn/bn_rand.c b/app/openssl/crypto/bn/bn_rand.c
index b376c28f..55676f07 100644
--- a/app/openssl/crypto/bn/bn_rand.c
+++ b/app/openssl/crypto/bn/bn_rand.c
@@ -114,6 +114,7 @@
 #include "cryptlib.h"
 #include "bn_lcl.h"
 #include <openssl/rand.h>
+#include <openssl/sha.h>
 
 static int bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom)
 	{
@@ -303,3 +304,72 @@ int	BN_pseudo_rand_range(BIGNUM *r, const BIGNUM *range)
 	{
 	return bn_rand_range(1, r, range);
 	}
+
+#ifndef OPENSSL_NO_SHA512
+/* BN_generate_dsa_nonce generates a random number 0 <= out < range. Unlike
+ * BN_rand_range, it also includes the contents of |priv| and |message| in the
+ * generation so that an RNG failure isn't fatal as long as |priv| remains
+ * secret. This is intended for use in DSA and ECDSA where an RNG weakness
+ * leads directly to private key exposure unless this function is used. */
+int BN_generate_dsa_nonce(BIGNUM *out, const BIGNUM *range, const BIGNUM* priv,
+			  const unsigned char *message, size_t message_len,
+			  BN_CTX *ctx)
+	{
+	SHA512_CTX sha;
+	/* We use 512 bits of random data per iteration to
+	 * ensure that we have at least |range| bits of randomness. */
+	unsigned char random_bytes[64];
+	unsigned char digest[SHA512_DIGEST_LENGTH];
+	unsigned done, todo;
+	/* We generate |range|+8 bytes of random output. */
+	const unsigned num_k_bytes = BN_num_bytes(range) + 8;
+	unsigned char private_bytes[96];
+	unsigned char *k_bytes;
+	int ret = 0;
+
+	k_bytes = OPENSSL_malloc(num_k_bytes);
+	if (!k_bytes)
+		goto err;
+
+	/* We copy |priv| into a local buffer to avoid exposing its length. */
+	todo = sizeof(priv->d[0])*priv->top;
+	if (todo > sizeof(private_bytes))
+		{
+		/* No reasonable DSA or ECDSA key should have a private key
+		 * this large and we don't handle this case in order to avoid
+		 * leaking the length of the private key. */
+		BNerr(BN_F_BN_GENERATE_DSA_NONCE, BN_R_PRIVATE_KEY_TOO_LARGE);
+		goto err;
+		}
+	memcpy(private_bytes, priv->d, todo);
+	memset(private_bytes + todo, 0, sizeof(private_bytes) - todo);
+
+	for (done = 0; done < num_k_bytes;) {
+		if (RAND_bytes(random_bytes, sizeof(random_bytes)) != 1)
+			goto err;
+		SHA512_Init(&sha);
+		SHA512_Update(&sha, &done, sizeof(done));
+		SHA512_Update(&sha, private_bytes, sizeof(private_bytes));
+		SHA512_Update(&sha, message, message_len);
+		SHA512_Update(&sha, random_bytes, sizeof(random_bytes));
+		SHA512_Final(digest, &sha);
+
+		todo = num_k_bytes - done;
+		if (todo > SHA512_DIGEST_LENGTH)
+			todo = SHA512_DIGEST_LENGTH;
+		memcpy(k_bytes + done, digest, todo);
+		done += todo;
+	}
+
+	if (!BN_bin2bn(k_bytes, num_k_bytes, out))
+		goto err;
+	if (BN_mod(out, out, range, ctx) != 1)
+		goto err;
+	ret = 1;
+
+err:
+	if (k_bytes)
+		OPENSSL_free(k_bytes);
+	return ret;
+	}
+#endif  /* OPENSSL_NO_SHA512 */