s390/zcrypt_ep11misc: support API ordinal 6 with empty pin-blob

Secure execution guest environments require an empty pinblob in all
key generation and unwrap requests. Empty pinblobs are only available
in EP11 API ordinal 6 or higher.

Add an empty pinblob to key generation and unwrap requests, if the AP
secure binding facility is available. In all other cases, stay with
the empty pin tag (no pinblob) and the current API ordinals.

The EP11 API ordinal also needs to be considered when the pkey module
tries to figure out the list of eligible cards for key operations
with protected keys in secure execution environment.

These changes are transparent to userspace but required for running
an secure execution guest with handling key generate and key derive
(e.g. secure key to protected key) correct. Especially using EP11
secure keys with the kernel dm-crypt layer requires this patch.

Co-developed-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Holger Dengler <dengler@linux.ibm.com>
Reviewed-by: Ingo Franzki <ifranzki@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

1 files changed, 19 insertions, 8 deletions

diff --git a/drivers/s390/crypto/pkey_api.c b/drivers/s390/crypto/pkey_api.c
index 396a159afdf5..6cfb6b2340c9 100644
--- a/drivers/s390/crypto/pkey_api.c
+++ b/drivers/s390/crypto/pkey_api.c
@@ -263,7 +263,9 @@ static int pkey_clr2ep11key(const u8 *clrkey, size_t clrkeylen,
 
 	/* build a list of apqns suitable for ep11 keys with cpacf support */
 	rc = ep11_findcard2(&apqns, &nr_apqns, 0xFFFF, 0xFFFF,
-			    ZCRYPT_CEX7, EP11_API_V, NULL);
+			    ZCRYPT_CEX7,
+			    ap_is_se_guest() ? EP11_API_V6 : EP11_API_V4,
+			    NULL);
 	if (rc)
 		goto out;
 
@@ -299,7 +301,8 @@ static int pkey_ep11key2pkey(const u8 *key, size_t keylen,
 
 	/* build a list of apqns suitable for this key */
 	rc = ep11_findcard2(&apqns, &nr_apqns, 0xFFFF, 0xFFFF,
-			    ZCRYPT_CEX7, EP11_API_V,
+			    ZCRYPT_CEX7,
+			    ap_is_se_guest() ? EP11_API_V6 : EP11_API_V4,
 			    ep11_kb_wkvp(key, keylen));
 	if (rc)
 		goto out;
@@ -902,6 +905,7 @@ static int pkey_verifykey2(const u8 *key, size_t keylen,
 	} else if (hdr->type == TOKTYPE_NON_CCA &&
 		   hdr->version == TOKVER_EP11_AES) {
 		struct ep11keyblob *kb = (struct ep11keyblob *)key;
+		int api;
 
 		rc = ep11_check_aes_key(debug_info, 3, key, keylen, 1);
 		if (rc)
@@ -911,8 +915,9 @@ static int pkey_verifykey2(const u8 *key, size_t keylen,
 		if (ksize)
 			*ksize = kb->head.bitlen;
 
+		api = ap_is_se_guest() ? EP11_API_V6 : EP11_API_V4;
 		rc = ep11_findcard2(&_apqns, &_nr_apqns, *cardnr, *domain,
-				    ZCRYPT_CEX7, EP11_API_V,
+				    ZCRYPT_CEX7, api,
 				    ep11_kb_wkvp(key, keylen));
 		if (rc)
 			goto out;
@@ -926,6 +931,7 @@ static int pkey_verifykey2(const u8 *key, size_t keylen,
 	} else if (hdr->type == TOKTYPE_NON_CCA &&
 		   hdr->version == TOKVER_EP11_AES_WITH_HEADER) {
 		struct ep11kblob_header *kh = (struct ep11kblob_header *)key;
+		int api;
 
 		rc = ep11_check_aes_key_with_hdr(debug_info, 3,
 						 key, keylen, 1);
@@ -936,8 +942,9 @@ static int pkey_verifykey2(const u8 *key, size_t keylen,
 		if (ksize)
 			*ksize = kh->bitlen;
 
+		api = ap_is_se_guest() ? EP11_API_V6 : EP11_API_V4;
 		rc = ep11_findcard2(&_apqns, &_nr_apqns, *cardnr, *domain,
-				    ZCRYPT_CEX7, EP11_API_V,
+				    ZCRYPT_CEX7, api,
 				    ep11_kb_wkvp(key, keylen));
 		if (rc)
 			goto out;
@@ -1056,7 +1063,7 @@ static int pkey_apqns4key(const u8 *key, size_t keylen, u32 flags,
 			return -EINVAL;
 		if (kb->attr & EP11_BLOB_PKEY_EXTRACTABLE) {
 			minhwtype = ZCRYPT_CEX7;
-			api = EP11_API_V;
+			api = ap_is_se_guest() ? EP11_API_V6 : EP11_API_V4;
 		}
 		rc = ep11_findcard2(&_apqns, &_nr_apqns, 0xFFFF, 0xFFFF,
 				    minhwtype, api, kb->wkvp);
@@ -1072,7 +1079,7 @@ static int pkey_apqns4key(const u8 *key, size_t keylen, u32 flags,
 			return -EINVAL;
 		if (kb->attr & EP11_BLOB_PKEY_EXTRACTABLE) {
 			minhwtype = ZCRYPT_CEX7;
-			api = EP11_API_V;
+			api = ap_is_se_guest() ? EP11_API_V6 : EP11_API_V4;
 		}
 		rc = ep11_findcard2(&_apqns, &_nr_apqns, 0xFFFF, 0xFFFF,
 				    minhwtype, api, kb->wkvp);
@@ -1182,11 +1189,13 @@ static int pkey_apqns4keytype(enum pkey_key_type ktype,
 		   ktype == PKEY_TYPE_EP11_AES ||
 		   ktype == PKEY_TYPE_EP11_ECC) {
 		u8 *wkvp = NULL;
+		int api;
 
 		if (flags & PKEY_FLAGS_MATCH_CUR_MKVP)
 			wkvp = cur_mkvp;
+		api = ap_is_se_guest() ? EP11_API_V6 : EP11_API_V4;
 		rc = ep11_findcard2(&_apqns, &_nr_apqns, 0xFFFF, 0xFFFF,
-				    ZCRYPT_CEX7, EP11_API_V, wkvp);
+				    ZCRYPT_CEX7, api, wkvp);
 		if (rc)
 			goto out;
 
@@ -2160,7 +2169,9 @@ static ssize_t pkey_ep11_aes_attr_read(enum pkey_key_size keybits,
 
 	/* build a list of apqns able to generate an cipher key */
 	rc = ep11_findcard2(&apqns, &nr_apqns, 0xFFFF, 0xFFFF,
-			    ZCRYPT_CEX7, EP11_API_V, NULL);
+			    ZCRYPT_CEX7,
+			    ap_is_se_guest() ? EP11_API_V6 : EP11_API_V4,
+			    NULL);
 	if (rc)
 		return rc;