libhsmd: First working build script for libhsmd-python

Changelog-Added: libhsmd: Added python bindings for `libhsmd`

Makefile

@@ -81,6 +81,8 @@ endif
 # (method=thread to support xdist)
 PYTEST_OPTS := -v -p no:logging $(PYTEST_OPTS)
 PYTHONPATH=$(shell pwd)/contrib/pyln-client:$(shell pwd)/contrib/pyln-testing:$(shell pwd)/contrib/pyln-proto/:$(shell pwd)/external/lnprototest:$(shell pwd)/contrib/pyln-spec/bolt1:$(shell pwd)/contrib/pyln-spec/bolt2:$(shell pwd)/contrib/pyln-spec/bolt4:$(shell pwd)/contrib/pyln-spec/bolt7
+# Collect generated python files to be excluded from lint checks
+PYTHON_GENERATED=
 
 # This is where we add new features as bitcoin adds them.
 FEATURES :=
@@ -320,6 +322,7 @@ include devtools/Makefile
 include tools/Makefile
 include plugins/Makefile
 include tests/plugins/Makefile
+include contrib/libhsmd_python/Makefile
 ifneq ($(FUZZING),0)
 	include tests/fuzz/Makefile
 endif
@@ -458,7 +461,7 @@ check-python-flake8:
 	@# E501 line too long (N > 79 characters)
 	@# E731 do not assign a lambda expression, use a def
 	@# W503: line break before binary operator
-	@flake8 --ignore=E501,E731,W503 ${PYSRC}
+	@flake8 --ignore=E501,E731,W503 --exclude $(shell echo ${PYTHON_GENERATED} | sed 's/ \+/,/g') ${PYSRC}
 
 check-pytest-pyln-proto:
 	PATH=$(PYLN_PATH) PYTHONPATH=$(PYTHONPATH) $(PYTEST) contrib/pyln-proto/tests/

common/bolt12.h

@@ -104,8 +104,7 @@ bool bolt12_check_signature(const struct tlv_field *fields,
 			    const char *messagename,
 			    const char *fieldname,
 			    const struct pubkey32 *key,
-			    const struct bip340sig *sig)
-	NO_NULL_ARGS;
+			    const struct bip340sig *sig);
 
 /* Given a tal_arr of chains, does it contain this chain? */
 bool bolt12_chains_match(const struct bitcoin_blkid *chains,

contrib/libhsmd_python/Makefile

@@ -0,0 +1,11 @@
+#!/usr/bin/make
+
+LIBHSMD_PY_GEN_FILES := contrib/libhsmd_python/swig_wrap.c \
+	contrib/libhsmd_python/libhsmd.py
+
+PYTHON_GENERATED += contrib/libhsmd_python/libhsmd.py
+
+# Swig by default generates stubs in the file's directory, which is
+# what we want.
+$(LIBHSMD_PY_GEN_FILES): contrib/libhsmd_python/swig.i $(HSMD_SRC)
+	swig -python -builtin contrib/libhsmd_python/swig.i

contrib/libhsmd_python/libhsmd.py

@@ -0,0 +1,111 @@
+# This file was automatically generated by SWIG (http://www.swig.org).
+# Version 3.0.12
+#
+# Do not make changes to this file unless you know what you are doing--modify
+# the SWIG interface file instead.
+
+from sys import version_info as _swig_python_version_info
+if _swig_python_version_info >= (2, 7, 0):
+    def swig_import_helper():
+        import importlib
+        pkg = __name__.rpartition('.')[0]
+        mname = '.'.join((pkg, '_libhsmd')).lstrip('.')
+        try:
+            return importlib.import_module(mname)
+        except ImportError:
+            return importlib.import_module('_libhsmd')
+    _libhsmd = swig_import_helper()
+    del swig_import_helper
+elif _swig_python_version_info >= (2, 6, 0):
+    def swig_import_helper():
+        from os.path import dirname
+        import imp
+        fp = None
+        try:
+            fp, pathname, description = imp.find_module('_libhsmd', [dirname(__file__)])
+        except ImportError:
+            import _libhsmd
+            return _libhsmd
+        try:
+            _mod = imp.load_module('_libhsmd', fp, pathname, description)
+        finally:
+            if fp is not None:
+                fp.close()
+        return _mod
+    _libhsmd = swig_import_helper()
+    del swig_import_helper
+else:
+    import _libhsmd
+# pull in all the attributes from _libhsmd
+if __name__.rpartition('.')[0] != '':
+    if _swig_python_version_info >= (2, 7, 0):
+        try:
+            from ._libhsmd import *
+        except ImportError:
+            from _libhsmd import *
+    else:
+        from _libhsmd import *
+else:
+    from _libhsmd import *
+del _swig_python_version_info
+
+try:
+    _swig_property = property
+except NameError:
+    pass  # Python < 2.2 doesn't have 'property'.
+
+try:
+    import builtins as __builtin__
+except ImportError:
+    import __builtin__
+
+def _swig_setattr_nondynamic(self, class_type, name, value, static=1):
+    if (name == "thisown"):
+        return self.this.own(value)
+    if (name == "this"):
+        if type(value).__name__ == 'SwigPyObject':
+            self.__dict__[name] = value
+            return
+    method = class_type.__swig_setmethods__.get(name, None)
+    if method:
+        return method(self, value)
+    if (not static):
+        if _newclass:
+            object.__setattr__(self, name, value)
+        else:
+            self.__dict__[name] = value
+    else:
+        raise AttributeError("You cannot add attributes to %s" % self)
+
+
+def _swig_setattr(self, class_type, name, value):
+    return _swig_setattr_nondynamic(self, class_type, name, value, 0)
+
+
+def _swig_getattr(self, class_type, name):
+    if (name == "thisown"):
+        return self.this.own()
+    method = class_type.__swig_getmethods__.get(name, None)
+    if method:
+        return method(self)
+    raise AttributeError("'%s' object has no attribute '%s'" % (class_type.__name__, name))
+
+
+def _swig_repr(self):
+    try:
+        strthis = "proxy of " + self.this.__repr__()
+    except __builtin__.Exception:
+        strthis = ""
+    return "<%s.%s; %s >" % (self.__class__.__module__, self.__class__.__name__, strthis,)
+
+try:
+    _object = object
+    _newclass = 1
+except __builtin__.Exception:
+    class _object:
+        pass
+    _newclass = 0
+
+# This file is compatible with both classic and new-style classes.
+
+

contrib/libhsmd_python/libhsmd_python.c

@@ -0,0 +1,74 @@
+#include <ccan/str/hex/hex.h>
+#include <libhsmd_python.h>
+
+char *init(char *hex_hsm_secret, char *network_name) {
+	const struct bip32_key_version *key_version;
+	struct secret sec;
+	u8 *response;
+	setup_locale();
+	if (sodium_init() == -1) {
+		fprintf(
+		    stderr,
+		    "Could not initialize libsodium. Maybe not enough entropy"
+		    " available ?");
+		return NULL;
+	}
+
+	wally_init(0);
+	secp256k1_ctx = wally_get_secp_context();
+
+	sodium_mlock(&sec, sizeof(sec));
+	if (!hex_decode(hex_hsm_secret, strlen(hex_hsm_secret), sec.data,
+			sizeof(sec.data))) {
+		fprintf(stderr,
+			"Expected hex_hsm_secret of length 64, got %zu\n",
+			strlen(hex_hsm_secret));
+		return NULL;
+	}
+
+	/* Look up chainparams by their name */
+	chainparams = chainparams_for_network(network_name);
+	if (chainparams == NULL) {
+		fprintf(stderr, "Could not find chainparams for network %s\n",
+			network_name);
+		return NULL;
+	}
+
+	key_version = &chainparams->bip32_key_version;
+
+	response = hsmd_init(sec, *key_version);
+	sodium_munlock(&sec, sizeof(sec));
+
+	char *res = tal_hex(NULL, response);
+	tal_free(response);
+	return res;
+}
+
+char *handle(long long cap, long long dbid, char *peer_id, char *hexmsg) {
+	const tal_t *ctx = tal_arr(NULL, u8, 0);
+	size_t res_len;
+	u8 *response, *request = tal_hexdata(ctx, hexmsg, strlen(hexmsg));
+	char *res;
+	struct hsmd_client *client;
+	struct node_id *peer = NULL;
+	printf("%llu: %s\n", cap, hexmsg);
+	if (peer_id != NULL) {
+		peer = tal(ctx, struct node_id);
+		node_id_from_hexstr(hexmsg, strlen(hexmsg), peer);
+		client = hsmd_client_new_peer(ctx, cap, dbid, peer, NULL);
+	} else {
+		client = hsmd_client_new_main(ctx, cap, NULL);
+	}
+	response = hsmd_handle_client_message(NULL, client, request);
+	printf("%s\n", tal_hex(ctx, response));
+	if (response == NULL)
+		return tal_free(ctx);
+
+	res = tal_hex(NULL, response);
+	res_len = hex_str_size(tal_bytelen(response));
+	res = malloc(res_len);
+	hex_encode(response, tal_bytelen(response), res, res_len);
+
+	tal_free(ctx);
+	return res;
+}

contrib/libhsmd_python/libhsmd_python.h

@@ -0,0 +1,8 @@
+#ifndef LIGHTNING_CONTRIB_LIBHSMD_PYTHON_LIBHSMD_PYTHON_H
+#define LIGHTNING_CONTRIB_LIBHSMD_PYTHON_LIBHSMD_PYTHON_H
+
+#include <hsmd/libhsmd.h>
+char *handle(long long cap, long long dbid, char *peer_id, char *msg);
+char *init(char *hex_hsm_secret, char *network_name);
+
+#endif /* LIGHTNING_CONTRIB_LIBHSMD_PYTHON_LIBHSMD_PYTHON_H */