s390-tools/s390-tools-sles15sp2-30-zkey-Add-helper-function-to-convert-secure-keys-betw.patch

Subject: zkey: Add helper function to convert secure keys between key types
From: Ingo Franzki <ifranzki@linux.ibm.com>

Summary:     zkey: Add support for CCA AES CIPHER keys
Description: With CCA 5 there is a new secure key type, the so called 
             variable length symmetric cipher key token. This token format
             can hold AES keys with size 128, 192 and 256 bits together
             with additional attributes cryptographic bound to the key
             token. The attributes may limit the usage of the key, for
             example restrict export or usability scope. So this key type
             is considered to be even more secure than the traditional 
             secure key token. This key token type is also called "CCA
             AES CIPHER key", where the formerly used key token is called
             "CCA AES DATA key".
             The zkey as well as the zkey-cryptsetup tools are enhanced
             to support AES CIPHER keys. That is, zkey can manage AES DATA 
             keys, as well as AES CIPHER keys. The key type must be specified
             at key generation time, the default is to generate AED DATA
             keys.
Upstream-ID: 7d4b1e18b6195f48414f42b4655f900872fed1e7
Problem-ID:  SEC1717

Upstream-Description:

             zkey: Add helper function to convert secure keys between key types

             Add a helper function to convert a secure key from key type
             CCA-AESDATA to CCA-AESCIPHER.

             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/cca.c |  171 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 zkey/cca.h |   22 +++++++
 2 files changed, 192 insertions(+), 1 deletion(-)

--- a/zkey/cca.c
+++ b/zkey/cca.c
@@ -55,6 +55,14 @@ static void print_CCA_error(int return_c
 			warnx("The secure key has a CCA master key "
 			      "verification pattern that is not valid");
 			break;
+		case 90:
+			warnx("The operation has been rejected due to access "
+			      "control checking");
+			break;
+		case 2143:
+			warnx("The operation has been rejected due to key "
+			      "export restrictions of the secure key");
+			break;
 		}
 		break;
 	case 12:
@@ -154,12 +162,16 @@ int load_cca_library(struct cca_lib *cca
 	/* Cryptographic Resource Deallocate function */
 	cca->dll_CSUACRD = (t_CSUACRD)dlsym(cca->lib_csulcca, "CSUACRD");
 
+	/* Get the Key Translate 2 function */
+	cca->dll_CSNBKTR2 = (t_CSNBKTR2)dlsym(cca->lib_csulcca, "CSNBKTR2");
+
 	if (cca->dll_CSUACFV == NULL ||
 	    cca->dll_CSNBKTC == NULL ||
 	    cca->dll_CSNBKTC2 == NULL ||
 	    cca->dll_CSUACFQ == NULL ||
 	    cca->dll_CSUACRA == NULL ||
-	    cca->dll_CSUACRD == NULL) {
+	    cca->dll_CSUACRD == NULL ||
+	    cca->dll_CSNBKTR2 == NULL) {
 		pr_verbose(verbose, "%s", dlerror());
 		warnx("The command requires the IBM CCA Host Libraries and "
 		      "Tools.\nFor the supported environments and downloads, "
@@ -729,3 +741,160 @@ void print_msg_for_cca_envvars(const cha
 	util_print_indented(msg, 0);
 	free(msg);
 }
+
+/*
+ * Convert a secure key of type CCA-AESDATA into a secure key of type
+ * CCA-AESCIPHER.
+ *
+ * @param[in] cca       the CCA library structure
+ * @param[in] input_key the secure key to convert
+ * @param[in] input_key_size the size of the secure key to convert
+ * @param[in] output_key buffer for the converted secure key
+ * @param[in/out] output_key_size on input: size of the output buffer.
+ *                                on exit: size of the converted secure key
+ * @param[in] verbose          if true, verbose messages are printed
+ *
+ * @returns 0 on success, a negative errno in case of an error.
+ */
+int convert_aes_data_to_cipher_key(struct cca_lib *cca,
+				   u8 *input_key, unsigned int input_key_size,
+				   u8 *output_key,
+				   unsigned int *output_key_size,
+				   bool verbose)
+{
+	long input_token_size, output_token_size, zero = 0;
+	long exit_data_len = 0, rule_array_count = 0;
+	unsigned char *input_token, *output_token;
+	unsigned char rule_array[8 * 2] = { 0, };
+	unsigned char null_token[64] = { 0, };
+	long null_token_len = sizeof(null_token);
+	unsigned char exit_data[4] = { 0, };
+	struct aescipherkeytoken *cipherkey;
+	long return_code, reason_code;
+	struct cca_version version;
+	unsigned char buffer[800];
+	int rc;
+
+	util_assert(cca != NULL, "Internal error: cca is NULL");
+	util_assert(input_key != NULL, "Internal error: input_key is NULL");
+	util_assert(output_key != NULL, "Internal error: output_key is NULL");
+	util_assert(output_key_size != NULL,
+		    "Internal error: output_key_size is NULL");
+
+	if (is_cca_aes_cipher_key(input_key, input_key_size)) {
+		warnx("Invalid key-type specified");
+		return -EINVAL;
+	}
+
+	if (*output_key_size < (is_xts_key(input_key, input_key_size) ?
+				2 * AESCIPHER_KEY_SIZE : AESCIPHER_KEY_SIZE))
+		return -EINVAL;
+
+	/*
+	 * We need a CCA firmware version 6.3.27 or later to support
+	 * conversion of secure keys that are exportable to CPACF protected keys
+	 */
+	rc = get_cca_adapter_version(cca, &version, verbose);
+	if (rc != 0)
+		return rc;
+	if (version.ver < 6 ||
+	    (version.ver == 6 && version.rel < 3) ||
+	    (version.ver == 6 && version.rel < 3 && version.mod < 27)) {
+		util_print_indented("The used CCA firmware version does not "
+				    "support converting a secure key that can "
+				    "be used with the PAES cipher. The "
+				    "required CCA firmware version is 6.3.27 "
+				    "or later. For the supported environments "
+				    "and updates, see: " CCA_WEB_PAGE, 0);
+		return -ENOTSUP;
+	}
+
+	input_token = input_key;
+	input_token_size = AESDATA_KEY_SIZE;
+	output_token = buffer;
+	output_token_size = sizeof(buffer);
+	memset(buffer, 0, sizeof(buffer));
+
+	memcpy(rule_array, "AES     ", 8);
+	memcpy(rule_array + 8, "REFORMAT", 8);
+	rule_array_count = 2;
+
+	cca->dll_CSNBKTR2(&return_code, &reason_code,
+			  &exit_data_len, exit_data,
+			  &rule_array_count, rule_array,
+			  &input_token_size, input_token,
+			  &null_token_len, null_token,
+			  &zero, NULL,
+			  &output_token_size, output_token);
+
+	pr_verbose(verbose, "CSNBKTR2 (Key Translate2) "
+		   "returned: return_code: %ld, reason_code: %ld", return_code,
+		   reason_code);
+	if (return_code != 0) {
+		print_CCA_error(return_code, reason_code);
+		return -EIO;
+	}
+
+	pr_verbose(verbose, "output_token_size: %lu", output_token_size);
+	if (output_token_size > (long)AESCIPHER_KEY_SIZE) {
+		pr_verbose(verbose, "Output key token too large");
+		return -EINVAL;
+	}
+
+	/*
+	 * Check if the converted key allows export to CPACF protected key.
+	 * If not, then the CCA host library or firmware code level is too low.
+	 */
+	cipherkey = (struct aescipherkeytoken *)buffer;
+	if ((cipherkey->kmf1 & 0x0800) == 0) {
+		util_print_indented("The used CCA firmware version does not "
+				    "support converting a secure key that can "
+				    "be used with the PAES cipher. The "
+				    "required CCA firmware version is 6.3.27 "
+				    "or later. For the supported environments "
+				    "and updates, see: " CCA_WEB_PAGE, 0);
+		return -ENOTSUP;
+	}
+
+	memset(output_key, 0, *output_key_size);
+	memcpy(output_key, buffer, output_token_size);
+	*output_key_size = AESCIPHER_KEY_SIZE;
+
+	if (is_xts_key(input_key, input_key_size)) {
+		input_token = input_key + AESDATA_KEY_SIZE;
+		input_token_size = AESDATA_KEY_SIZE;
+		output_token = buffer;
+		output_token_size = sizeof(buffer);
+		memset(buffer, 0, sizeof(buffer));
+
+		cca->dll_CSNBKTR2(&return_code, &reason_code,
+				  &exit_data_len, exit_data,
+				  &rule_array_count, rule_array,
+				  &input_token_size, input_token,
+				  &null_token_len, null_token,
+				  &zero, NULL,
+				  &output_token_size, output_token);
+
+		pr_verbose(verbose, "CSNBKTR2 (Key Translate2) "
+			   "returned: return_code: %ld, reason_code: %ld",
+			   return_code, reason_code);
+		if (return_code != 0) {
+			print_CCA_error(return_code, reason_code);
+			return -EIO;
+		}
+
+		pr_verbose(verbose, "output_token_size: %lu",
+			   output_token_size);
+		if (output_token_size > (long)AESCIPHER_KEY_SIZE) {
+			pr_verbose(verbose, "Output key token too large");
+			return -EINVAL;
+		}
+
+		memcpy(output_key + AESCIPHER_KEY_SIZE, buffer,
+		       output_token_size);
+		*output_key_size += AESCIPHER_KEY_SIZE;
+	}
+
+	return 0;
+}
+
--- a/zkey/cca.h
+++ b/zkey/cca.h
@@ -68,6 +68,21 @@ typedef void (*t_CSUACRD)(long *return_c
 			  long *ressource_name_length,
 			  unsigned char *ressource_name);
 
+typedef void (*t_CSNBKTR2)(long *return_code,
+			   long *reason_code,
+			   long *exit_data_length,
+			   unsigned char *exit_data,
+			   long *rule_array_count,
+			   unsigned char *rule_array,
+			   long *input_key_token_length,
+			   unsigned char *input_key_token,
+			   long *input_KEK_key_identifier_length,
+			   unsigned char *input_KEK_key_identifier,
+			   long *output_KEK_key_identifier_length,
+			   unsigned char *output_KEK_key_identifier,
+			   long *output_key_token_length,
+			   unsigned char *output_key_token);
+
 struct cca_version {
 	unsigned int ver;
 	unsigned int rel;
@@ -82,6 +97,7 @@ struct cca_lib {
 	t_CSUACFQ dll_CSUACFQ;
 	t_CSUACRA dll_CSUACRA;
 	t_CSUACRD dll_CSUACRD;
+	t_CSNBKTR2 dll_CSNBKTR2;
 	struct cca_version version;
 };
 
@@ -102,4 +118,10 @@ int select_cca_adapter_by_mkvp(struct cc
 
 void print_msg_for_cca_envvars(const char *key_name);
 
+int convert_aes_data_to_cipher_key(struct cca_lib *cca,
+				   u8 *input_key, unsigned int input_key_size,
+				   u8 *output_key,
+				   unsigned int *output_key_size,
+				   bool verbose);
+
 #endif