Crypto: Align to PSA Crypto headers 0.1.0a

This patch updates the PSA Crypto API headers to version
0.1.0a. The Crypto service implementation is updated when
needed to make sure the service is buildable and functional.

Change-Id: I63709db0d87f449012d0c8355658f1af1583b3ab
Signed-off-by: Antonio de Angelis <antonio.deangelis@arm.com>
diff --git a/interface/include/psa_crypto_sizes.h b/interface/include/psa_crypto_sizes.h
new file mode 100644
index 0000000..07b52e4
--- /dev/null
+++ b/interface/include/psa_crypto_sizes.h
@@ -0,0 +1,255 @@
+/*
+ * Copyright (c) 2019, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ */
+/**
+ * \file psa_crypto_sizes.h
+ *
+ * \brief PSA cryptography module: buffer size macros
+ *
+ * \note This file may not be included directly. Applications must
+ * include psa_crypto.h.
+ *
+ * This file contains the definitions of macros that are useful to
+ * compute buffer sizes. The signatures and semantics of these macros
+ * are standardized, but the definitions are not, because they depend on
+ * the available algorithms and, in some cases, on permitted tolerances
+ * on buffer sizes.
+ *
+ * In implementations with isolation between the application and the
+ * cryptography module, implementers should take care to ensure that
+ * the definitions that are exposed to applications match what the
+ * module implements.
+ *
+ * Macros that compute sizes whose values do not depend on the
+ * implementation are in psa_crypto.h.
+ */
+
+#ifndef PSA_CRYPTO_SIZES_H
+#define PSA_CRYPTO_SIZES_H
+
+/** \def PSA_HASH_MAX_SIZE
+ *
+ * Maximum size of a hash.
+ *
+ * This macro must expand to a compile-time constant integer. This value
+ * should be the maximum size of a hash supported by the implementation,
+ * in bytes, and must be no smaller than this maximum.
+ */
+#define PSA_HASH_MAX_SIZE 64
+#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 128
+
+/** \def PSA_MAC_MAX_SIZE
+ *
+ * Maximum size of a MAC.
+ *
+ * This macro must expand to a compile-time constant integer. This value
+ * should be the maximum size of a MAC supported by the implementation,
+ * in bytes, and must be no smaller than this maximum.
+ */
+/* All non-HMAC MACs have a maximum size that's smaller than the
+ * minimum possible value of PSA_HASH_MAX_SIZE in this implementation. */
+#define PSA_MAC_MAX_SIZE PSA_HASH_MAX_SIZE
+
+/* The maximum size of an RSA key on this implementation, in bits.
+ * This is a vendor-specific macro.
+ *
+ * Mbed Crypto does not set a hard limit on the size of RSA keys: any key
+ * whose parameters fit in a bignum is accepted. However large keys can
+ * induce a large memory usage and long computation times. Unlike other
+ * auxiliary macros in this file and in crypto.h, which reflect how the
+ * library is configured, this macro defines how the library is
+ * configured. This implementation refuses to import or generate an
+ * RSA key whose size is larger than the value defined here.
+ *
+ * Note that an implementation may set different size limits for different
+ * operations, and does not need to accept all key sizes up to the limit. */
+#define PSA_VENDOR_RSA_MAX_KEY_BITS 4096
+
+/* The maximum size of an ECC key on this implementation, in bits.
+ * This is a vendor-specific macro. */
+#define PSA_VENDOR_ECC_MAX_CURVE_BITS 0
+
+/** \def PSA_ASYMMETRIC_SIGNATURE_MAX_SIZE
+ *
+ * Maximum size of an asymmetric signature.
+ *
+ * This macro must expand to a compile-time constant integer. This value
+ * should be the maximum size of a MAC supported by the implementation,
+ * in bytes, and must be no smaller than this maximum.
+ */
+#define PSA_ASYMMETRIC_SIGNATURE_MAX_SIZE                               \
+    PSA_BITS_TO_BYTES(                                                  \
+        PSA_VENDOR_RSA_MAX_KEY_BITS > PSA_VENDOR_ECC_MAX_CURVE_BITS ?   \
+        PSA_VENDOR_RSA_MAX_KEY_BITS :                                   \
+        PSA_VENDOR_ECC_MAX_CURVE_BITS                                   \
+        )
+
+
+
+/** The size of the output of psa_mac_sign_finish(), in bytes.
+ *
+ * This is also the MAC size that psa_mac_verify_finish() expects.
+ *
+ * \param key_type      The type of the MAC key.
+ * \param key_bits      The size of the MAC key in bits.
+ * \param alg           A MAC algorithm (\c PSA_ALG_XXX value such that
+ *                      #PSA_ALG_IS_MAC(alg) is true).
+ *
+ * \return              The MAC size for the specified algorithm with
+ *                      the specified key parameters.
+ * \return              0 if the MAC algorithm is not recognized.
+ * \return              Either 0 or the correct size for a MAC algorithm that
+ *                      the implementation recognizes, but does not support.
+ * \return              Unspecified if the key parameters are not consistent
+ *                      with the algorithm.
+ */
+#define PSA_MAC_FINAL_SIZE(key_type, key_bits, alg)                     \
+    (PSA_ALG_IS_HMAC(alg) ? PSA_HASH_SIZE(PSA_ALG_HMAC_HASH(alg)) : \
+     PSA_ALG_IS_BLOCK_CIPHER_MAC(alg) ? PSA_BLOCK_CIPHER_BLOCK_SIZE(key_type) : \
+     0)
+
+/** The maximum size of the output of psa_aead_encrypt(), in bytes.
+ *
+ * If the size of the ciphertext buffer is at least this large, it is
+ * guaranteed that psa_aead_encrypt() will not fail due to an
+ * insufficient buffer size. Depending on the algorithm, the actual size of
+ * the ciphertext may be smaller.
+ *
+ * \param alg                 An AEAD algorithm
+ *                            (\c PSA_ALG_XXX value such that
+ *                            #PSA_ALG_IS_AEAD(alg) is true).
+ * \param plaintext_length    Size of the plaintext in bytes.
+ *
+ * \return                    The AEAD ciphertext size for the specified
+ *                            algorithm.
+ *                            If the AEAD algorithm is not recognized, return 0.
+ *                            An implementation may return either 0 or a
+ *                            correct size for an AEAD algorithm that it
+ *                            recognizes, but does not support.
+ */
+#define PSA_AEAD_ENCRYPT_OUTPUT_SIZE(alg, plaintext_length)     \
+    (PSA_AEAD_TAG_SIZE(alg) != 0 ?                              \
+     (plaintext_length) + PSA_AEAD_TAG_SIZE(alg) :              \
+     0)
+
+/** The maximum size of the output of psa_aead_decrypt(), in bytes.
+ *
+ * If the size of the plaintext buffer is at least this large, it is
+ * guaranteed that psa_aead_decrypt() will not fail due to an
+ * insufficient buffer size. Depending on the algorithm, the actual size of
+ * the plaintext may be smaller.
+ *
+ * \param alg                 An AEAD algorithm
+ *                            (\c PSA_ALG_XXX value such that
+ *                            #PSA_ALG_IS_AEAD(alg) is true).
+ * \param ciphertext_length   Size of the plaintext in bytes.
+ *
+ * \return                    The AEAD ciphertext size for the specified
+ *                            algorithm.
+ *                            If the AEAD algorithm is not recognized, return 0.
+ *                            An implementation may return either 0 or a
+ *                            correct size for an AEAD algorithm that it
+ *                            recognizes, but does not support.
+ */
+#define PSA_AEAD_DECRYPT_OUTPUT_SIZE(alg, ciphertext_length)    \
+    (PSA_AEAD_TAG_SIZE(alg) != 0 ?                              \
+     (plaintext_length) - PSA_AEAD_TAG_SIZE(alg) :              \
+     0)
+
+/** Safe signature buffer size for psa_asymmetric_sign().
+ *
+ * This macro returns a safe buffer size for a signature using a key
+ * of the specified type and size, with the specified algorithm.
+ * Note that the actual size of the signature may be smaller
+ * (some algorithms produce a variable-size signature).
+ *
+ * \warning This function may call its arguments multiple times or
+ *          zero times, so you should not pass arguments that contain
+ *          side effects.
+ *
+ * \param key_type  An asymmetric key type (this may indifferently be a
+ *                  key pair type or a public key type).
+ * \param key_bits  The size of the key in bits.
+ * \param alg       The signature algorithm.
+ *
+ * \return If the parameters are valid and supported, return
+ *         a buffer size in bytes that guarantees that
+ *         psa_asymmetric_sign() will not fail with
+ *         #PSA_ERROR_BUFFER_TOO_SMALL.
+ *         If the parameters are a valid combination that is not supported
+ *         by the implementation, this macro either shall return either a
+ *         sensible size or 0.
+ *         If the parameters are not valid, the
+ *         return value is unspecified.
+ */
+#define PSA_ASYMMETRIC_SIGN_OUTPUT_SIZE(key_type, key_bits, alg)        \
+    (PSA_KEY_TYPE_IS_RSA(key_type) ? ((void)alg, PSA_BITS_TO_BYTES(key_bits)) : \
+     PSA_KEY_TYPE_IS_ECC(key_type) ? PSA_ECDSA_SIGNATURE_SIZE(key_bits) : \
+     ((void)alg, 0))
+
+/** Safe output buffer size for psa_asymmetric_encrypt().
+ *
+ * This macro returns a safe buffer size for a ciphertext produced using
+ * a key of the specified type and size, with the specified algorithm.
+ * Note that the actual size of the ciphertext may be smaller, depending
+ * on the algorithm.
+ *
+ * \warning This function may call its arguments multiple times or
+ *          zero times, so you should not pass arguments that contain
+ *          side effects.
+ *
+ * \param key_type  An asymmetric key type (this may indifferently be a
+ *                  key pair type or a public key type).
+ * \param key_bits  The size of the key in bits.
+ * \param alg       The signature algorithm.
+ *
+ * \return If the parameters are valid and supported, return
+ *         a buffer size in bytes that guarantees that
+ *         psa_asymmetric_encrypt() will not fail with
+ *         #PSA_ERROR_BUFFER_TOO_SMALL.
+ *         If the parameters are a valid combination that is not supported
+ *         by the implementation, this macro either shall return either a
+ *         sensible size or 0.
+ *         If the parameters are not valid, the
+ *         return value is unspecified.
+ */
+#define PSA_ASYMMETRIC_ENCRYPT_OUTPUT_SIZE(key_type, key_bits, alg)     \
+    (PSA_KEY_TYPE_IS_RSA(key_type) ?                                    \
+     ((void)alg, PSA_BITS_TO_BYTES(key_bits)) :                         \
+     0)
+
+/** Safe output buffer size for psa_asymmetric_decrypt().
+ *
+ * This macro returns a safe buffer size for a ciphertext produced using
+ * a key of the specified type and size, with the specified algorithm.
+ * Note that the actual size of the ciphertext may be smaller, depending
+ * on the algorithm.
+ *
+ * \warning This function may call its arguments multiple times or
+ *          zero times, so you should not pass arguments that contain
+ *          side effects.
+ *
+ * \param key_type  An asymmetric key type (this may indifferently be a
+ *                  key pair type or a public key type).
+ * \param key_bits  The size of the key in bits.
+ * \param alg       The signature algorithm.
+ *
+ * \return If the parameters are valid and supported, return
+ *         a buffer size in bytes that guarantees that
+ *         psa_asymmetric_decrypt() will not fail with
+ *         #PSA_ERROR_BUFFER_TOO_SMALL.
+ *         If the parameters are a valid combination that is not supported
+ *         by the implementation, this macro either shall return either a
+ *         sensible size or 0.
+ *         If the parameters are not valid, the
+ *         return value is unspecified.
+ */
+#define PSA_ASYMMETRIC_DECRYPT_OUTPUT_SIZE(key_type, key_bits, alg)     \
+    (PSA_KEY_TYPE_IS_RSA(key_type) ?                                    \
+     PSA_BITS_TO_BYTES(key_bits) - PSA_RSA_MINIMUM_PADDING_SIZE(alg) :  \
+     0)
+
+#endif /* PSA_CRYPTO_SIZES_H */