CBMC: Prove keccak_f1600_x2_native based on keccak_f1600_x2_v84a_asm

Signed-off-by: Matthias J. Kannwischer <matthias@kannwischer.eu>

Author: mkannwischer

dev/fips202/aarch64/src/fips202_native_aarch64.h

@@ -31,7 +31,12 @@ __contract__(
 );
 
 #define mlk_keccak_f1600_x2_v84a_asm MLK_NAMESPACE(keccak_f1600_x2_v84a_asm)
-void mlk_keccak_f1600_x2_v84a_asm(uint64_t *state, uint64_t const *rc);
+void mlk_keccak_f1600_x2_v84a_asm(uint64_t *state, uint64_t const *rc)
+__contract__(
+  requires(memory_no_alias(state, sizeof(uint64_t) * 25 * 2))
+  requires(rc == mlk_keccakf1600_round_constants)
+  assigns(memory_slice(state, sizeof(uint64_t) * 25 * 2))
+);
 
 #define mlk_keccak_f1600_x2_v8a_v84a_asm_hybrid \
   MLK_NAMESPACE(keccak_f1600_x2_v8a_v84a_asm_hybrid)

mlkem/fips202/native/aarch64/src/fips202_native_aarch64.h

@@ -31,7 +31,12 @@ __contract__(
 );
 
 #define mlk_keccak_f1600_x2_v84a_asm MLK_NAMESPACE(keccak_f1600_x2_v84a_asm)
-void mlk_keccak_f1600_x2_v84a_asm(uint64_t *state, uint64_t const *rc);
+void mlk_keccak_f1600_x2_v84a_asm(uint64_t *state, uint64_t const *rc)
+__contract__(
+  requires(memory_no_alias(state, sizeof(uint64_t) * 25 * 2))
+  requires(rc == mlk_keccakf1600_round_constants)
+  assigns(memory_slice(state, sizeof(uint64_t) * 25 * 2))
+);
 
 #define mlk_keccak_f1600_x2_v8a_v84a_asm_hybrid \
   MLK_NAMESPACE(keccak_f1600_x2_v8a_v84a_asm_hybrid)

proofs/cbmc/keccak_f1600_x2_native_aarch64_v84a/Makefile

@@ -0,0 +1,55 @@
+# Copyright (c) The mlkem-native project authors
+# SPDX-License-Identifier: Apache-2.0 OR ISC OR MIT
+
+include ../Makefile_params.common
+
+HARNESS_ENTRY = harness
+HARNESS_FILE = keccak_f1600_x2_native_aarch64_v84a_harness
+
+# This should be a unique identifier for this proof, and will appear on the
+# Litani dashboard. It can be human-readable and contain spaces if you wish.
+PROOF_UID = keccak_f1600_x2_native_aarch64_v84a
+
+DEFINES += -DMLK_CONFIG_USE_NATIVE_BACKEND_FIPS202 -DMLK_CONFIG_FIPS202_BACKEND_FILE="\"$(SRCDIR)/mlkem/fips202/native/aarch64/x2_v84a.h\"" -DMLK_CHECK_APIS -D__ARM_FEATURE_SHA3
+INCLUDES +=
+
+REMOVE_FUNCTION_BODY +=
+UNWINDSET +=
+
+PROOF_SOURCES += $(PROOFDIR)/$(HARNESS_FILE).c
+PROJECT_SOURCES += $(SRCDIR)/mlkem/fips202/native/aarch64/src/keccakf1600_round_constants.c 
+
+CHECK_FUNCTION_CONTRACTS=mlk_keccak_f1600_x2_native
+USE_FUNCTION_CONTRACTS=mlk_keccak_f1600_x2_v84a_asm
+APPLY_LOOP_CONTRACTS=on
+USE_DYNAMIC_FRAMES=1
+
+# Disable any setting of EXTERNAL_SAT_SOLVER, and choose SMT backend instead
+EXTERNAL_SAT_SOLVER=
+CBMCFLAGS=--bitwuzla
+
+FUNCTION_NAME = keccak_f1600_x2_native_aarch64_v84a
+
+# If this proof is found to consume huge amounts of RAM, you can set the
+# EXPENSIVE variable. With new enough versions of the proof tools, this will
+# restrict the number of EXPENSIVE CBMC jobs running at once. See the
+# documentation in Makefile.common under the "Job Pools" heading for details.
+# EXPENSIVE = true
+
+# This function is large enough to need...
+CBMC_OBJECT_BITS = 8
+
+# If you require access to a file-local ("static") function or object to conduct
+# your proof, set the following (and do not include the original source file
+# ("mlkem/poly.c") in PROJECT_SOURCES).
+# REWRITTEN_SOURCES = $(PROOFDIR)/<__SOURCE_FILE_BASENAME__>.i
+# include ../Makefile.common
+# $(PROOFDIR)/<__SOURCE_FILE_BASENAME__>.i_SOURCE = $(SRCDIR)/mlkem/poly.c
+# $(PROOFDIR)/<__SOURCE_FILE_BASENAME__>.i_FUNCTIONS = foo bar
+# $(PROOFDIR)/<__SOURCE_FILE_BASENAME__>.i_OBJECTS = baz
+# Care is required with variables on the left-hand side: REWRITTEN_SOURCES must
+# be set before including Makefile.common, but any use of variables on the
+# left-hand side requires those variables to be defined. Hence, _SOURCE,
+# _FUNCTIONS, _OBJECTS is set after including Makefile.common.
+
+include ../Makefile.common

proofs/cbmc/keccak_f1600_x2_native_aarch64_v84a/keccak_f1600_x2_native_aarch64_v84a_harness.c

@@ -0,0 +1,13 @@
+// Copyright (c) The mlkem-native project authors
+// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+// SPDX-License-Identifier: MIT-0
+
+#include <stdint.h>
+
+void mlk_keccak_f1600_x2_native(uint64_t *state);
+
+void harness(void)
+{
+  uint64_t *s;
+  mlk_keccak_f1600_x2_native(s);
+}