diff --git a/crypto/asymmetric_keys/asymmetric_type.c b/crypto/asymmetric_keys/asymmetric_type.c
index ad8af3d70ac..3df31899146 100644
--- a/crypto/asymmetric_keys/asymmetric_type.c
+++ b/crypto/asymmetric_keys/asymmetric_type.c
@@ -36,16 +36,23 @@ static DECLARE_RWSEM(asymmetric_key_parsers_sem);
  * find_asymmetric_key - Find a key by ID.
  * @keyring: The keys to search.
  * @id_0: The first ID to look for or NULL.
- * @id_1: The second ID to look for or NULL.
- * @partial: Use partial match if true, exact if false.
+ * @id_1: The second ID to look for or NULL, matched together with @id_0
+ * against @keyring keys' id[0] and id[1].
+ * @id_2: The fallback ID to match against @keyring keys' id[2] if both of the
+ * other IDs are NULL.
+ * @partial: Use partial match for @id_0 and @id_1 if true, exact if false.
  *
  * Find a key in the given keyring by identifier.  The preferred identifier is
  * the id_0 and the fallback identifier is the id_1.  If both are given, the
- * lookup is by the former, but the latter must also match.
+ * former is matched (exactly or partially) against either of the sought key's
+ * identifiers and the latter must match the found key's second identifier
+ * exactly.  If both are missing, id_2 must match the sought key's third
+ * identifier exactly.
  */
 struct key *find_asymmetric_key(struct key *keyring,
 				const struct asymmetric_key_id *id_0,
 				const struct asymmetric_key_id *id_1,
+				const struct asymmetric_key_id *id_2,
 				bool partial)
 {
 	struct key *key;
@@ -54,14 +61,17 @@ struct key *find_asymmetric_key(struct key *keyring,
 	char *req, *p;
 	int len;
 
-	BUG_ON(!id_0 && !id_1);
+	BUG_ON(!id_0 && !id_1 && !id_2);
 
 	if (id_0) {
 		lookup = id_0->data;
 		len = id_0->len;
-	} else {
+	} else if (id_1) {
 		lookup = id_1->data;
 		len = id_1->len;
+	} else {
+		lookup = id_2->data;
+		len = id_2->len;
 	}
 
 	/* Construct an identifier "id:<keyid>". */
@@ -69,7 +79,10 @@ struct key *find_asymmetric_key(struct key *keyring,
 	if (!req)
 		return ERR_PTR(-ENOMEM);
 
-	if (partial) {
+	if (!id_0 && !id_1) {
+		*p++ = 'd';
+		*p++ = 'n';
+	} else if (partial) {
 		*p++ = 'i';
 		*p++ = 'd';
 	} else {
@@ -185,8 +198,8 @@ bool asymmetric_key_id_partial(const struct asymmetric_key_id *kid1,
 EXPORT_SYMBOL_GPL(asymmetric_key_id_partial);
 
 /**
- * asymmetric_match_key_ids - Search asymmetric key IDs
- * @kids: The list of key IDs to check
+ * asymmetric_match_key_ids - Search asymmetric key IDs 1 & 2
+ * @kids: The pair of key IDs to check
  * @match_id: The key ID we're looking for
  * @match: The match function to use
  */
@@ -200,7 +213,7 @@ static bool asymmetric_match_key_ids(
 
 	if (!kids || !match_id)
 		return false;
-	for (i = 0; i < ARRAY_SIZE(kids->id); i++)
+	for (i = 0; i < 2; i++)
 		if (match(kids->id[i], match_id))
 			return true;
 	return false;
@@ -244,7 +257,7 @@ struct asymmetric_key_id *asymmetric_key_hex_to_key_id(const char *id)
 }
 
 /*
- * Match asymmetric keys by an exact match on an ID.
+ * Match asymmetric keys by an exact match on one of the first two IDs.
  */
 static bool asymmetric_key_cmp(const struct key *key,
 			       const struct key_match_data *match_data)
@@ -257,7 +270,7 @@ static bool asymmetric_key_cmp(const struct key *key,
 }
 
 /*
- * Match asymmetric keys by a partial match on an IDs.
+ * Match asymmetric keys by a partial match on one of the first two IDs.
  */
 static bool asymmetric_key_cmp_partial(const struct key *key,
 				       const struct key_match_data *match_data)
@@ -269,6 +282,18 @@ static bool asymmetric_key_cmp_partial(const struct key *key,
 					asymmetric_key_id_partial);
 }
 
+/*
+ * Match asymmetric keys by an exact match on the third IDs.
+ */
+static bool asymmetric_key_cmp_name(const struct key *key,
+				    const struct key_match_data *match_data)
+{
+	const struct asymmetric_key_ids *kids = asymmetric_key_ids(key);
+	const struct asymmetric_key_id *match_id = match_data->preparsed;
+
+	return kids && asymmetric_key_id_same(kids->id[2], match_id);
+}
+
 /*
  * Preparse the match criterion.  If we don't set lookup_type and cmp,
  * the default will be an exact match on the key description.
@@ -276,8 +301,9 @@ static bool asymmetric_key_cmp_partial(const struct key *key,
  * There are some specifiers for matching key IDs rather than by the key
  * description:
  *
- *	"id:<id>" - find a key by partial match on any available ID
- *	"ex:<id>" - find a key by exact match on any available ID
+ *	"id:<id>" - find a key by partial match on one of the first two IDs
+ *	"ex:<id>" - find a key by exact match on one of the first two IDs
+ *	"dn:<id>" - find a key by exact match on the third ID
  *
  * These have to be searched by iteration rather than by direct lookup because
  * the key is hashed according to its description.
@@ -301,6 +327,11 @@ static int asymmetric_key_match_preparse(struct key_match_data *match_data)
 		   spec[1] == 'x' &&
 		   spec[2] == ':') {
 		id = spec + 3;
+	} else if (spec[0] == 'd' &&
+		   spec[1] == 'n' &&
+		   spec[2] == ':') {
+		id = spec + 3;
+		cmp = asymmetric_key_cmp_name;
 	} else {
 		goto default_match;
 	}
diff --git a/crypto/asymmetric_keys/pkcs7_trust.c b/crypto/asymmetric_keys/pkcs7_trust.c
index b531df2013c..9a87c34ed17 100644
--- a/crypto/asymmetric_keys/pkcs7_trust.c
+++ b/crypto/asymmetric_keys/pkcs7_trust.c
@@ -48,7 +48,7 @@ static int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7,
 		 * keys.
 		 */
 		key = find_asymmetric_key(trust_keyring,
-					  x509->id, x509->skid, false);
+					  x509->id, x509->skid, NULL, false);
 		if (!IS_ERR(key)) {
 			/* One of the X.509 certificates in the PKCS#7 message
 			 * is apparently the same as one we already trust.
@@ -82,7 +82,7 @@ static int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7,
 		key = find_asymmetric_key(trust_keyring,
 					  last->sig->auth_ids[0],
 					  last->sig->auth_ids[1],
-					  false);
+					  NULL, false);
 		if (!IS_ERR(key)) {
 			x509 = last;
 			pr_devel("sinfo %u: Root cert %u signer is key %x\n",
@@ -97,7 +97,7 @@ static int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7,
 	 * the signed info directly.
 	 */
 	key = find_asymmetric_key(trust_keyring,
-				  sinfo->sig->auth_ids[0], NULL, false);
+				  sinfo->sig->auth_ids[0], NULL, NULL, false);
 	if (!IS_ERR(key)) {
 		pr_devel("sinfo %u: Direct signer is key %x\n",
 			 sinfo->index, key_serial(key));
diff --git a/crypto/asymmetric_keys/restrict.c b/crypto/asymmetric_keys/restrict.c
index 84cefe3b358..822746836c8 100644
--- a/crypto/asymmetric_keys/restrict.c
+++ b/crypto/asymmetric_keys/restrict.c
@@ -87,7 +87,7 @@ int restrict_link_by_signature(struct key *dest_keyring,
 	sig = payload->data[asym_auth];
 	if (!sig)
 		return -ENOPKG;
-	if (!sig->auth_ids[0] && !sig->auth_ids[1])
+	if (!sig->auth_ids[0] && !sig->auth_ids[1] && !sig->auth_ids[2])
 		return -ENOKEY;
 
 	if (ca_keyid && !asymmetric_key_id_partial(sig->auth_ids[1], ca_keyid))
@@ -96,7 +96,7 @@ int restrict_link_by_signature(struct key *dest_keyring,
 	/* See if we have a key that signed this one. */
 	key = find_asymmetric_key(trust_keyring,
 				  sig->auth_ids[0], sig->auth_ids[1],
-				  false);
+				  sig->auth_ids[2], false);
 	if (IS_ERR(key))
 		return -ENOKEY;
 
@@ -108,11 +108,11 @@ int restrict_link_by_signature(struct key *dest_keyring,
 	return ret;
 }
 
-static bool match_either_id(const struct asymmetric_key_ids *pair,
+static bool match_either_id(const struct asymmetric_key_id **pair,
 			    const struct asymmetric_key_id *single)
 {
-	return (asymmetric_key_id_same(pair->id[0], single) ||
-		asymmetric_key_id_same(pair->id[1], single));
+	return (asymmetric_key_id_same(pair[0], single) ||
+		asymmetric_key_id_same(pair[1], single));
 }
 
 static int key_or_keyring_common(struct key *dest_keyring,
@@ -140,20 +140,22 @@ static int key_or_keyring_common(struct key *dest_keyring,
 	sig = payload->data[asym_auth];
 	if (!sig)
 		return -ENOPKG;
-	if (!sig->auth_ids[0] && !sig->auth_ids[1])
+	if (!sig->auth_ids[0] && !sig->auth_ids[1] && !sig->auth_ids[2])
 		return -ENOKEY;
 
 	if (trusted) {
 		if (trusted->type == &key_type_keyring) {
 			/* See if we have a key that signed this one. */
 			key = find_asymmetric_key(trusted, sig->auth_ids[0],
-						  sig->auth_ids[1], false);
+						  sig->auth_ids[1],
+						  sig->auth_ids[2], false);
 			if (IS_ERR(key))
 				key = NULL;
 		} else if (trusted->type == &key_type_asymmetric) {
-			const struct asymmetric_key_ids *signer_ids;
+			const struct asymmetric_key_id **signer_ids;
 
-			signer_ids = asymmetric_key_ids(trusted);
+			signer_ids = (const struct asymmetric_key_id **)
+				asymmetric_key_ids(trusted)->id;
 
 			/*
 			 * The auth_ids come from the candidate key (the
@@ -164,22 +166,29 @@ static int key_or_keyring_common(struct key *dest_keyring,
 			 * The signer_ids are identifiers for the
 			 * signing key specified for dest_keyring.
 			 *
-			 * The first auth_id is the preferred id, and
-			 * the second is the fallback. If only one
-			 * auth_id is present, it may match against
-			 * either signer_id. If two auth_ids are
-			 * present, the first auth_id must match one
-			 * signer_id and the second auth_id must match
-			 * the second signer_id.
+			 * The first auth_id is the preferred id, 2nd and
+			 * 3rd are the fallbacks. If excatly one of
+			 * auth_ids[0] and auth_ids[1] is present, it may
+			 * match either signer_ids[0] or signed_ids[1].
+			 * If both are present the first one may match
+			 * either signed_id but the second one must match
+			 * the second signer_id. If neither of them is
+			 * available, auth_ids[2] is matched against
+			 * signer_ids[2] as a fallback.
 			 */
-			if (!sig->auth_ids[0] || !sig->auth_ids[1]) {
+			if (!sig->auth_ids[0] && !sig->auth_ids[1]) {
+				if (asymmetric_key_id_same(signer_ids[2],
+							   sig->auth_ids[2]))
+					key = __key_get(trusted);
+
+			} else if (!sig->auth_ids[0] || !sig->auth_ids[1]) {
 				const struct asymmetric_key_id *auth_id;
 
 				auth_id = sig->auth_ids[0] ?: sig->auth_ids[1];
 				if (match_either_id(signer_ids, auth_id))
 					key = __key_get(trusted);
 
-			} else if (asymmetric_key_id_same(signer_ids->id[1],
+			} else if (asymmetric_key_id_same(signer_ids[1],
 							  sig->auth_ids[1]) &&
 				   match_either_id(signer_ids,
 						   sig->auth_ids[0])) {
@@ -193,7 +202,8 @@ static int key_or_keyring_common(struct key *dest_keyring,
 	if (check_dest && !key) {
 		/* See if the destination has a key that signed this one. */
 		key = find_asymmetric_key(dest_keyring, sig->auth_ids[0],
-					  sig->auth_ids[1], false);
+					  sig->auth_ids[1], sig->auth_ids[2],
+					  false);
 		if (IS_ERR(key))
 			key = NULL;
 	}
diff --git a/crypto/asymmetric_keys/x509_cert_parser.c b/crypto/asymmetric_keys/x509_cert_parser.c
index 6d003096b5b..083405eb80c 100644
--- a/crypto/asymmetric_keys/x509_cert_parser.c
+++ b/crypto/asymmetric_keys/x509_cert_parser.c
@@ -441,8 +441,18 @@ int x509_note_issuer(void *context, size_t hdrlen,
 		     const void *value, size_t vlen)
 {
 	struct x509_parse_context *ctx = context;
+	struct asymmetric_key_id *kid;
+
 	ctx->cert->raw_issuer = value;
 	ctx->cert->raw_issuer_size = vlen;
+
+	if (!ctx->cert->sig->auth_ids[2]) {
+		kid = asymmetric_key_generate_id(value, vlen, "", 0);
+		if (IS_ERR(kid))
+			return PTR_ERR(kid);
+		ctx->cert->sig->auth_ids[2] = kid;
+	}
+
 	return x509_fabricate_name(ctx, hdrlen, tag, &ctx->cert->issuer, vlen);
 }
 
diff --git a/crypto/asymmetric_keys/x509_public_key.c b/crypto/asymmetric_keys/x509_public_key.c
index 3d45161b271..fe14cae115b 100644
--- a/crypto/asymmetric_keys/x509_public_key.c
+++ b/crypto/asymmetric_keys/x509_public_key.c
@@ -223,6 +223,13 @@ static int x509_key_preparse(struct key_preparsed_payload *prep)
 		goto error_free_desc;
 	kids->id[0] = cert->id;
 	kids->id[1] = cert->skid;
+	kids->id[2] = asymmetric_key_generate_id(cert->raw_subject,
+						 cert->raw_subject_size,
+						 "", 0);
+	if (IS_ERR(kids->id[2])) {
+		ret = PTR_ERR(kids->id[2]);
+		goto error_free_kids;
+	}
 
 	/* We're pinning the module by being linked against it */
 	__module_get(public_key_subtype.owner);
@@ -239,8 +246,11 @@ static int x509_key_preparse(struct key_preparsed_payload *prep)
 	cert->skid = NULL;
 	cert->sig = NULL;
 	desc = NULL;
+	kids = NULL;
 	ret = 0;
 
+error_free_kids:
+	kfree(kids);
 error_free_desc:
 	kfree(desc);
 error_free_cert:
diff --git a/include/crypto/public_key.h b/include/crypto/public_key.h
index f603325c0c3..68f7aa2a7e5 100644
--- a/include/crypto/public_key.h
+++ b/include/crypto/public_key.h
@@ -36,7 +36,7 @@ extern void public_key_free(struct public_key *key);
  * Public key cryptography signature data
  */
 struct public_key_signature {
-	struct asymmetric_key_id *auth_ids[2];
+	struct asymmetric_key_id *auth_ids[3];
 	u8 *s;			/* Signature */
 	u8 *digest;
 	u32 s_size;		/* Number of bytes in signature */
diff --git a/include/keys/asymmetric-type.h b/include/keys/asymmetric-type.h
index c432fdb8547..6c5d4963e15 100644
--- a/include/keys/asymmetric-type.h
+++ b/include/keys/asymmetric-type.h
@@ -53,7 +53,7 @@ struct asymmetric_key_id {
 };
 
 struct asymmetric_key_ids {
-	void		*id[2];
+	void		*id[3];
 };
 
 extern bool asymmetric_key_id_same(const struct asymmetric_key_id *kid1,
@@ -81,6 +81,7 @@ const struct public_key *asymmetric_key_public_key(const struct key *key)
 extern struct key *find_asymmetric_key(struct key *keyring,
 				       const struct asymmetric_key_id *id_0,
 				       const struct asymmetric_key_id *id_1,
+				       const struct asymmetric_key_id *id_2,
 				       bool partial);
 
 /*
