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diff --git a/TPM2-Plugin/lib/include/tpm2_alg_util.h b/TPM2-Plugin/lib/include/tpm2_alg_util.h
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+//**********************************************************************;
+// Copyright (c) 2017, Intel Corporation
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice,
+// this list of conditions and the following disclaimer.
+//
+// 2. Redistributions in binary form must reproduce the above copyright notice,
+// this list of conditions and the following disclaimer in the documentation
+// and/or other materials provided with the distribution.
+//
+// 3. Neither the name of Intel Corporation nor the names of its contributors
+// may be used to endorse or promote products derived from this software without
+// specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+// THE POSSIBILITY OF SUCH DAMAGE.
+//**********************************************************************;
+#ifndef LIB_TPM2_ALG_UTIL_H_
+#define LIB_TPM2_ALG_UTIL_H_
+
+#include <stdbool.h>
+
+#include <sapi/tpm20.h>
+
+/**
+ * Iterator callback routine for iterating over known algorithm name and value
+ * pairs.
+ * @param id
+ *  The algorithm id.
+ * @param name
+ *  The associated "nice-name".
+ * @param userdata
+ *  A user supplied data pointer.
+ * @return
+ *  True to stop iterating, false to keep iterating.
+ */
+typedef bool (*tpm2_alg_util_alg_iteraror)(TPM2_ALG_ID id, const char *name, void *userdata);
+
+/**
+ * Iterate over the algorithm name-value pairs calling the iterator callback for each pair.
+ * @param iterator
+ *  The iterator callback function.
+ * @param userdata
+ *  A pointer to user supplied data, this is passed to the iterator for each call.
+ */
+void tpm2_alg_util_for_each_alg(tpm2_alg_util_alg_iteraror iterator, void *userdata);
+
+/**
+ * Convert a "nice-name" string to an algorithm id.
+ * @param name
+ *  The "nice-name" to convert.
+ * @return
+ *  TPM2_ALG_ERROR on error, or a valid algorithm identifier.
+ */
+TPM2_ALG_ID tpm2_alg_util_strtoalg(const char *name);
+
+/**
+ * Convert an id to a nice-name.
+ * @param id
+ *  The id to convert.
+ * @return
+ *  The nice-name.
+ */
+const char *tpm2_alg_util_algtostr(TPM2_ALG_ID id);
+
+/**
+ * Converts either a string from algrotithm number or algorithm nice-name to
+ * an algorithm id.
+ * @param optarg
+ *  The string to convert from an algorithm number or nice name.
+ * @return
+ *  TPM2_ALG_ERROR on error or the algorithm id.
+ */
+TPM2_ALG_ID tpm2_alg_util_from_optarg(char *optarg);
+
+/**
+ * Detects if an algorithm is considered a hashing algorithm.
+ * @param id
+ *  The algorithm id to check.
+ * @return
+ *  True if it is a hash algorithm, False otherwise.
+ */
+bool tpm2_alg_util_is_hash_alg(TPM2_ALG_ID id);
+
+/**
+ * Contains the information from parsing an argv style vector of strings for
+ * pcr digest language specifications.
+ */
+typedef struct tpm2_pcr_digest_spec tpm2_pcr_digest_spec;
+struct tpm2_pcr_digest_spec {
+    TPML_DIGEST_VALUES digests;
+    TPMI_DH_PCR pcr_index;
+};
+
+/**
+ * Parses an argv array that contains a digest specification at each location
+ * within argv.
+ *
+ * The digest specification is as follows:
+ *   - A pcr identifier as understood by strtoul with 0 as the base.
+ *   - A colon followed by the algorithm hash specification.
+ *   - The algorithm hash specification is as follows:
+ *       - The algorithm friendly name or raw numerical as understood by
+ *         strtoul with a base of 0.
+ *       - An equals sign
+ *       - The hex hash value,
+ *
+ *   This all distills to a string that looks like this:
+ *   <pcr index>:<hash alg id>=<hash value>
+ *
+ *   Example:
+ *   "4:sha=f1d2d2f924e986ac86fdf7b36c94bcdf32beec15"
+ *
+ *   Note:
+ *   Multiple specifications of PCR and hash are OK. Multiple hashes
+ *   cause the pcr to be extended with both hashes. Multiple same PCR
+ *   values cause the PCR to be extended multiple times. Extension
+ *   is done in order from left to right as specified.
+ *
+ *   At most 5 hash extensions per PCR entry are supported. This
+ *   is to keep the parser simple.
+ *
+ * @param sapi_context
+ *  The system API context for hashing files with the tpm. This can
+ *  be NULL if the argument vector doesn't have a file spec for the hash.
+ * @param argv
+ *  The argv of digest specifications to parse.
+ * @param len
+ *  The number of digest specifications to parse.
+ * @param digests
+ *  An array of tpm2_pcr_digest_spec big enough to hold len items.
+ * @return
+ *  True if parsing was successful, False otherwise.
+ *  @note
+ *  This function logs errors via LOG_ERR.
+ */
+bool pcr_parse_digest_list(char **argv, int len,
+        tpm2_pcr_digest_spec *digest_spec);
+
+/**
+ * Retrieves the size of a hash in bytes for a given hash
+ * algorithm or 0 if unknown/not found.
+ * @param id
+ *  The HASH algorithm identifier.
+ * @return
+ *  0 on failure or the size of the hash bytes.
+ */
+UINT16 tpm2_alg_util_get_hash_size(TPMI_ALG_HASH id);
+
+/**
+ * Extracts the plain signature data without any headers
+ *
+ * Communicates errors via LOG_ERR.
+ *
+ * @param size
+ *  Will receive the number of bytes stored in buffer.
+ * @signature The actual signature struct to extract the plain signature from.
+ * @return
+ *  Returns a buffer filled with the extracted signature or NULL on error.
+ *  Needs to be free()'d by the caller.
+ */
+UINT8* tpm2_extract_plain_signature(UINT16 *size, TPMT_SIGNATURE *signature);
+
+/**
+ * Retrieves an approproate signature scheme (scheme) signable by
+ * specified key (keyHandle) and hash algorithm (halg).
+ * @param sapi_context
+ *  System API context for tpm
+ * @param keyHandle
+ *  Handle to key used in signing operation
+ * @param halg
+ *  Hash algoritm for message
+ * @param scheme
+ *  Signature scheme output
+ * @return
+ *  True if successful
+ *  False otherwise, and scheme is left unmodified
+ */
+bool get_signature_scheme(TSS2_SYS_CONTEXT *sapi_context,
+        TPMI_DH_OBJECT keyHandle, TPMI_ALG_HASH halg,
+        TPMT_SIG_SCHEME *scheme);
+
+#endif /* LIB_TPM2_ALG_UTIL_H_ */