ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/crypto/asymmetric_keys/tpm_parser.c b/marvell/linux/crypto/asymmetric_keys/tpm_parser.c
new file mode 100644
index 0000000..96405d8
--- /dev/null
+++ b/marvell/linux/crypto/asymmetric_keys/tpm_parser.c
@@ -0,0 +1,102 @@
+// SPDX-License-Identifier: GPL-2.0
+#define pr_fmt(fmt) "TPM-PARSER: "fmt
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <keys/asymmetric-subtype.h>
+#include <keys/asymmetric-parser.h>
+#include <crypto/asym_tpm_subtype.h>
+#include "tpm.asn1.h"
+
+struct tpm_parse_context {
+ const void *blob;
+ u32 blob_len;
+};
+
+/*
+ * Note the key data of the ASN.1 blob.
+ */
+int tpm_note_key(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct tpm_parse_context *ctx = context;
+
+ ctx->blob = value;
+ ctx->blob_len = vlen;
+
+ return 0;
+}
+
+/*
+ * Parse a TPM-encrypted private key blob.
+ */
+static struct tpm_key *tpm_parse(const void *data, size_t datalen)
+{
+ struct tpm_parse_context ctx;
+ long ret;
+
+ memset(&ctx, 0, sizeof(ctx));
+
+ /* Attempt to decode the private key */
+ ret = asn1_ber_decoder(&tpm_decoder, &ctx, data, datalen);
+ if (ret < 0)
+ goto error;
+
+ return tpm_key_create(ctx.blob, ctx.blob_len);
+
+error:
+ return ERR_PTR(ret);
+}
+/*
+ * Attempt to parse a data blob for a key as a TPM private key blob.
+ */
+static int tpm_key_preparse(struct key_preparsed_payload *prep)
+{
+ struct tpm_key *tk;
+
+ /*
+ * TPM 1.2 keys are max 2048 bits long, so assume the blob is no
+ * more than 4x that
+ */
+ if (prep->datalen > 256 * 4)
+ return -EMSGSIZE;
+
+ tk = tpm_parse(prep->data, prep->datalen);
+
+ if (IS_ERR(tk))
+ return PTR_ERR(tk);
+
+ /* We're pinning the module by being linked against it */
+ __module_get(asym_tpm_subtype.owner);
+ prep->payload.data[asym_subtype] = &asym_tpm_subtype;
+ prep->payload.data[asym_key_ids] = NULL;
+ prep->payload.data[asym_crypto] = tk;
+ prep->payload.data[asym_auth] = NULL;
+ prep->quotalen = 100;
+ return 0;
+}
+
+static struct asymmetric_key_parser tpm_key_parser = {
+ .owner = THIS_MODULE,
+ .name = "tpm_parser",
+ .parse = tpm_key_preparse,
+};
+
+static int __init tpm_key_init(void)
+{
+ return register_asymmetric_key_parser(&tpm_key_parser);
+}
+
+static void __exit tpm_key_exit(void)
+{
+ unregister_asymmetric_key_parser(&tpm_key_parser);
+}
+
+module_init(tpm_key_init);
+module_exit(tpm_key_exit);
+
+MODULE_DESCRIPTION("TPM private key-blob parser");
+MODULE_LICENSE("GPL v2");