Subject: zkey: Add function to obtain the mkvp of a secure key
From: Ingo Franzki <ifranzki@linux.ibm.com>

Summary:     zkey: check master key consistency
Description: Enhances the zkey tool to perform a cross check whether the
             APQNs associated with a secure key have the same master key.
             Display the master key verification pattern of a secure key
             during the zkey validate command. This helps to better identify
             which master key is the correct one, in case of master key 
             inconsistencies.
             Select an appropriate APQN when re-enciphering a secure key.
             Re-enciphering is done using the CCA host library. Special
             handling is required to select an appropriate APQN for use with
             the CCA host library.
Upstream-ID: ea7cc9ea606dd879e4cdfae06a6f13d8fa3afff4
Problem-ID:  SEC1916

Upstream-Description:

             zkey: Add function to obtain the mkvp of a secure key

             A secure AES key token contains the master key verification pattern
             of the master key it is encrypted with. Add a function to obtain the
             master key verification pattern of a secure key token.

             Signed-off-by: Ingo Franzki <ifranzki@linux.ibm.com>
             Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
             Signed-off-by: Jan Hoeppner <hoeppner@linux.ibm.com>


Signed-off-by: Ingo Franzki <ifranzki@linux.ibm.com>
---
 zkey/pkey.c |   21 +++++++++++++++++++++
 zkey/pkey.h |    4 ++++
 2 files changed, 25 insertions(+)

--- a/zkey/pkey.c
+++ b/zkey/pkey.c
@@ -769,3 +769,24 @@ out:
 
 	return rc;
 }
+
+int get_master_key_verification_pattern(const u8 *secure_key,
+					size_t secure_key_size, u64 *mkvp,
+					bool verbose)
+{
+	struct secaeskeytoken *token = (struct secaeskeytoken *)secure_key;
+
+	util_assert(secure_key != NULL, "Internal error: secure_key is NULL");
+	util_assert(mkvp != NULL, "Internal error: mkvp is NULL");
+
+	if (secure_key_size < SECURE_KEY_SIZE) {
+		pr_verbose(verbose, "Size of secure key is too small: "
+			   "%lu expected %lu", secure_key_size,
+			   SECURE_KEY_SIZE);
+		return -EINVAL;
+	}
+
+	*mkvp = token->mkvp;
+
+	return 0;
+}
--- a/zkey/pkey.h
+++ b/zkey/pkey.h
@@ -112,4 +112,8 @@ int validate_secure_key(int pkey_fd,
 int generate_key_verification_pattern(const char *key, size_t key_size,
 				      char *vp, size_t vp_len, bool verbose);
 
+int get_master_key_verification_pattern(const u8 *secure_key,
+					size_t secure_key_size, u64 *mkvp,
+					bool verbose);
+
 #endif