1 files changed, 105 insertions, 0 deletions
diff --git a/core/tee/tee_cryp_concat_kdf.c b/core/tee/tee_cryp_concat_kdf.c
new file mode 100644
index 0000000..b0c7c3d
--- /dev/null
+++ b/core/tee/tee_cryp_concat_kdf.c
@@ -0,0 +1,105 @@
+/*
+ * Copyright (c) 2014, Linaro Limited
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <tee/tee_cryp_concat_kdf.h>
+#include <tee/tee_cryp_provider.h>
+#include <tee/tee_cryp_utl.h>
+#include <utee_defines.h>
+#include <stdlib.h>
+#include <string.h>
+
+TEE_Result tee_cryp_concat_kdf(uint32_t hash_id, const uint8_t *shared_secret,
+			       size_t shared_secret_len,
+			       const uint8_t *other_info,
+			       size_t other_info_len, uint8_t *derived_key,
+			       size_t derived_key_len)
+{
+	TEE_Result res;
+	size_t ctx_size, hash_len, i, n, sz;
+	void *ctx = NULL;
+	uint8_t tmp[TEE_MAX_HASH_SIZE];
+	uint32_t be_count;
+	uint8_t *out = derived_key;
+	uint32_t hash_algo = TEE_ALG_HASH_ALGO(hash_id);
+	const struct hash_ops *hash = &crypto_ops.hash;
+
+	if (!hash->get_ctx_size || !hash->init || !hash->update ||
+	    !hash->final) {
+		res = TEE_ERROR_NOT_IMPLEMENTED;
+		goto out;
+	}
+
+	res = hash->get_ctx_size(hash_algo, &ctx_size);
+	if (res != TEE_SUCCESS)
+		goto out;
+
+	ctx = malloc(ctx_size);
+	if (!ctx) {
+		res = TEE_ERROR_OUT_OF_MEMORY;
+		goto out;
+	}
+
+	res = tee_hash_get_digest_size(hash_algo, &hash_len);
+	if (res != TEE_SUCCESS)
+		goto out;
+
+	n = derived_key_len / hash_len;
+	sz = hash_len;
+	for (i = 1; i <= n + 1; i++) {
+		be_count = TEE_U32_TO_BIG_ENDIAN(i);
+
+		res = hash->init(ctx, hash_algo);
+		if (res != TEE_SUCCESS)
+			goto out;
+		res = hash->update(ctx, hash_algo, (uint8_t *)&be_count,
+				   sizeof(be_count));
+		if (res != TEE_SUCCESS)
+			goto out;
+		res = hash->update(ctx, hash_algo, shared_secret,
+				   shared_secret_len);
+		if (res != TEE_SUCCESS)
+			goto out;
+		if (other_info && other_info_len) {
+			res = hash->update(ctx, hash_algo, other_info,
+					   other_info_len);
+			if (res != TEE_SUCCESS)
+				goto out;
+		}
+		res = hash->final(ctx, hash_algo, tmp, sizeof(tmp));
+		if (res != TEE_SUCCESS)
+			goto out;
+
+		if (i == n + 1)
+			sz = derived_key_len % hash_len;
+		memcpy(out, tmp, sz);
+		out += sz;
+	}
+	res = TEE_SUCCESS;
+out:
+	free(ctx);
+	return res;
+}