add HMAC module

Author: picnixz

Modules/Setup

@@ -170,6 +170,7 @@ PYTHONPATH=$(COREPYTHONPATH)
 #_sha1 sha1module.c -I$(srcdir)/Modules/_hacl/include Modules/_hacl/libHacl_Hash_SHA1.a -D_BSD_SOURCE -D_DEFAULT_SOURCE
 #_sha2 sha2module.c -I$(srcdir)/Modules/_hacl/include Modules/_hacl/libHacl_Hash_SHA2.a -D_BSD_SOURCE -D_DEFAULT_SOURCE
 #_sha3 sha3module.c -I$(srcdir)/Modules/_hacl/include Modules/_hacl/libHacl_Hash_SHA3.a -D_BSD_SOURCE -D_DEFAULT_SOURCE
+#_hmac hmacmodule.c -I$(srcdir)/Modules/_hacl/include Modules/_hacl/libHacl_HMAC.a -D_BSD_SOURCE -D_DEFAULT_SOURCE
 
 # text encodings and unicode
 #_codecs_cn cjkcodecs/_codecs_cn.c

Modules/Setup.stdlib.in

@@ -84,6 +84,8 @@
 @MODULE__SHA3_TRUE@_sha3 sha3module.c -I$(srcdir)/Modules/_hacl/include Modules/_hacl/libHacl_Hash_SHA3.a -D_BSD_SOURCE -D_DEFAULT_SOURCE
 @MODULE__BLAKE2_TRUE@_blake2 blake2module.c -I$(srcdir)/Modules/_hacl/include Modules/_hacl/libHacl_Hash_Blake2.a -D_BSD_SOURCE -D_DEFAULT_SOURCE
 
+@MODULE__HMAC_TRUE@_hmac hmacmodule.c
+
 ############################################################################
 # XML and text
 

Modules/hmacmodule.c

@@ -0,0 +1,55 @@
+/*
+ * @author Bénédikt Tran
+ * @date December 2024
+ *
+ * Implement the HMAC algorithm as described by RFC 2104 using HACL*.
+ *
+ * Using HACL* implementation implicitly assumes that the caller wants
+ * a formally verified implementation. In particular, only algorithms
+ * given by their names will be recognized.
+ *
+ * Some algorithms exposed by `_hashlib` such as truncated SHA-2-512-224/256
+ * are not yet implemented by the HACL* project. Nonetheless, the supported
+ * HMAC algorithms form a subset of those supported by '_hashlib'.
+ */
+
+#ifndef Py_BUILD_CORE_BUILTIN
+#  define Py_BUILD_CORE_MODULE 1
+#endif
+
+#include "Python.h"
+
+// --- HMAC module clinic configuration ---------------------------------------
+
+/*[clinic input]
+module _hmac
+[clinic start generated code]*/
+/*[clinic end generated code: output=da39a3ee5e6b4b0d input=799f0f10157d561f]*/
+
+// --- HMAC module methods ----------------------------------------------------
+
+static PyMethodDef hmacmodule_methods[] = {
+    {NULL, NULL, 0, NULL} /* sentinel */
+};
+
+// --- HMAC module initialization and finalization functions ------------------
+
+static struct PyModuleDef_Slot hmacmodule_slots[] = {
+    {Py_mod_multiple_interpreters, Py_MOD_PER_INTERPRETER_GIL_SUPPORTED},
+    {Py_mod_gil, Py_MOD_GIL_NOT_USED},
+    {0, NULL} /* sentinel */
+};
+
+static struct PyModuleDef _hmacmodule = {
+    PyModuleDef_HEAD_INIT,
+    .m_name = "_hmac",
+    .m_size = sizeof(hmacmodule_state),
+    .m_methods = hmacmodule_methods,
+    .m_slots = hmacmodule_slots,
+};
+
+PyMODINIT_FUNC
+PyInit__hmac(void)
+{
+    return PyModuleDef_Init(&_hmacmodule);
+}

PC/config.c

@@ -25,6 +25,7 @@ extern PyObject* PyInit__statistics(void);
 extern PyObject* PyInit__sysconfig(void);
 extern PyObject* PyInit__typing(void);
 extern PyObject* PyInit__blake2(void);
+extern PyObject* PyInit__hmac(void);
 extern PyObject* PyInit_time(void);
 extern PyObject* PyInit__thread(void);
 #ifdef WIN32
@@ -102,6 +103,7 @@ struct _inittab _PyImport_Inittab[] = {
     {"_sha2", PyInit__sha2},
     {"_sha3", PyInit__sha3},
     {"_blake2", PyInit__blake2},
+    {"_hmac", PyInit__hmac},
     {"_sysconfig", PyInit__sysconfig},
     {"time", PyInit_time},
     {"_thread", PyInit__thread},

PCbuild/pythoncore.vcxproj

@@ -468,6 +468,7 @@
     <ClCompile Include="..\Modules\faulthandler.c" />
     <ClCompile Include="..\Modules\gcmodule.c" />
     <ClCompile Include="..\Modules\getbuildinfo.c" />
+    <ClCompile Include="..\Modules\hmacmodule.c" />
     <ClCompile Include="..\Modules\itertoolsmodule.c" />
     <ClCompile Include="..\Modules\main.c" />
     <ClCompile Include="..\Modules\mathmodule.c" />

PCbuild/pythoncore.vcxproj.filters

@@ -1010,6 +1010,9 @@
     <ClCompile Include="..\Modules\gcmodule.c">
       <Filter>Modules</Filter>
     </ClCompile>
+    <ClCompile Include="..\Modules\hmacmodule.c">
+      <Filter>Modules</Filter>
+    </ClCompile>
     <ClCompile Include="..\Modules\itertoolsmodule.c">
       <Filter>Modules</Filter>
     </ClCompile>

Python/stdlib_module_names.h

@@ -126,6 +126,7 @@ def clean_lines(text):
 Modules/sha2module.c	Modules/_hacl/include
 Modules/sha3module.c	Modules/_hacl/include
 Modules/blake2module.c	Modules/_hacl/include
+Modules/hmacmodule.c	Modules/_hacl/include
 Objects/stringlib/*.h	Objects
 
 # possible system-installed headers, just in case

Tools/c-analyzer/cpython/_parser.py

@@ -7898,6 +7898,13 @@ fi
 AC_SUBST([LIBHACL_SIMD256_FLAGS])
 AC_SUBST([LIBHACL_SIMD256_OBJS])
 
+dnl HMAC builtin library does not need OpenSSL for now. In the future
+dnl we might want to rely on OpenSSL EVP/NID interface or implement
+dnl our own for algorithm resolution.
+PY_STDLIB_MOD([_hmac], [], [],
+  [$LIBHACL_CFLAGS],
+  [$LIBHACL_CFLAGS Modules/_hacl/libHacl_HMAC.a])
+
 PY_STDLIB_MOD([_ctypes],
   [], [test "$have_libffi" = yes],
   [$NO_STRICT_OVERFLOW_CFLAGS $LIBFFI_CFLAGS], [$LIBFFI_LIBS])