1 files changed, 95 insertions, 0 deletions
diff --git a/crypto/asymmetric_keys/pkcs7_key_type.c b/crypto/asymmetric_keys/pkcs7_key_type.c
new file mode 100644
index 000000000..b930d3bbf
--- /dev/null
+++ b/crypto/asymmetric_keys/pkcs7_key_type.c
@@ -0,0 +1,95 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Testing module to load key from trusted PKCS#7 message
+ *
+ * Copyright (C) 2014 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#define pr_fmt(fmt) "PKCS7key: "fmt
+#include <linux/key.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/verification.h>
+#include <linux/key-type.h>
+#include <keys/user-type.h>
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("PKCS#7 testing key type");
+MODULE_AUTHOR("Red Hat, Inc.");
+
+static unsigned pkcs7_usage;
+module_param_named(usage, pkcs7_usage, uint, S_IWUSR | S_IRUGO);
+MODULE_PARM_DESC(pkcs7_usage,
+		 "Usage to specify when verifying the PKCS#7 message");
+
+/*
+ * Retrieve the PKCS#7 message content.
+ */
+static int pkcs7_view_content(void *ctx, const void *data, size_t len,
+			      size_t asn1hdrlen)
+{
+	struct key_preparsed_payload *prep = ctx;
+	const void *saved_prep_data;
+	size_t saved_prep_datalen;
+	int ret;
+
+	saved_prep_data = prep->data;
+	saved_prep_datalen = prep->datalen;
+	prep->data = data;
+	prep->datalen = len;
+
+	ret = user_preparse(prep);
+
+	prep->data = saved_prep_data;
+	prep->datalen = saved_prep_datalen;
+	return ret;
+}
+
+/*
+ * Preparse a PKCS#7 wrapped and validated data blob.
+ */
+static int pkcs7_preparse(struct key_preparsed_payload *prep)
+{
+	enum key_being_used_for usage = pkcs7_usage;
+
+	if (usage >= NR__KEY_BEING_USED_FOR) {
+		pr_err("Invalid usage type %d\n", usage);
+		return -EINVAL;
+	}
+
+	return verify_pkcs7_signature(NULL, 0,
+				      prep->data, prep->datalen,
+				      VERIFY_USE_SECONDARY_KEYRING, usage,
+				      pkcs7_view_content, prep);
+}
+
+/*
+ * user defined keys take an arbitrary string as the description and an
+ * arbitrary blob of data as the payload
+ */
+static struct key_type key_type_pkcs7 = {
+	.name			= "pkcs7_test",
+	.preparse		= pkcs7_preparse,
+	.free_preparse		= user_free_preparse,
+	.instantiate		= generic_key_instantiate,
+	.revoke			= user_revoke,
+	.destroy		= user_destroy,
+	.describe		= user_describe,
+	.read			= user_read,
+};
+
+/*
+ * Module stuff
+ */
+static int __init pkcs7_key_init(void)
+{
+	return register_key_type(&key_type_pkcs7);
+}
+
+static void __exit pkcs7_key_cleanup(void)
+{
+	unregister_key_type(&key_type_pkcs7);
+}
+
+module_init(pkcs7_key_init);
+module_exit(pkcs7_key_cleanup);