device/trezor: webusb transport added, cmake fixes

- webusb transport based on libusb added. Provides direct access to Trezor via USB, no need for Trezor bridge.
- trezor protocol message handler improved, no recursion used. Ready for upcoming integration tests.
- libusb (for docker) bumped from v1.0.9 to v1.0.22, newer version required for webusb transport, for device enumeration.
- cmake improvements and fixes. Cmake Trezor checks are moved to a dedicated CheckTrezor.cmake file. In case of a problem Trezor is excluded from build.
- ifdefs made consistent to Ledger.
- UDP Transport enumeration disabled by default in release mode

2 files changed, 54 insertions, 32 deletions

diff --git a/src/device_trezor/trezor/tools/README.md b/src/device_trezor/trezor/tools/README.md
index 91a8fb3f0..b176017ac 100644
--- a/src/device_trezor/trezor/tools/README.md
+++ b/src/device_trezor/trezor/tools/README.md
@@ -2,33 +2,28 @@
 
 ## Messages rebuild
 
-Install `protoc` for your distribution.
+Install `protoc` for your distribution. Requirements:
 
 - `protobuf-compiler`
 - `libprotobuf-dev`
-- `libprotoc-dev`
-- `python-protobuf`
+- `python`
 
-Python 3 is required. If you don't have python 3 quite an easy way is
-to use [pyenv].
 
-It is also advised to create own python virtual environment so dependencies
-are installed in this project-related virtual environment.
+Soft requirement: Python 3, can be easily installed with [pyenv].
 
-```bash
-python -m venv /
-```
+### Python 2
 
-Make sure your python has `protobuf` package installed
+Workaround if there is no Python3 available:
 
 ```bash
-pip install protobuf
+pip install backports.tempfile
 ```
 
-Regenerate messages:
+### Regenerate messages
 
-```
-./venv/bin/python3 src/device_trezor/trezor/tools/build_protob.py
+```bash
+cd src/device_trezor/trezor
+python tools/build_protob.py
 ```
 
 The messages regeneration is done also automatically via cmake.
diff --git a/src/device_trezor/trezor/tools/pb2cpp.py b/src/device_trezor/trezor/tools/pb2cpp.py
index eaa8a90ed..4d7cc775f 100644
--- a/src/device_trezor/trezor/tools/pb2cpp.py
+++ b/src/device_trezor/trezor/tools/pb2cpp.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python3
+#!/usr/bin/env python
 # Converts Google's protobuf python definitions of TREZOR wire messages
 # to plain-python objects as used in TREZOR Core and python-trezor
 
@@ -8,11 +8,19 @@ import os
 import re
 import shutil
 import subprocess
-import sys
 import glob
-import tempfile
 import hashlib
 
+try:
+    from tempfile import TemporaryDirectory
+except:
+    # Py2 backward compatibility, optionally installed by user
+    # pip install backports.tempfile
+    try:
+        from backports.tempfile import TemporaryDirectory
+    except:
+        raise EnvironmentError('TemporaryDirectory could not be imported. Try: pip install backports.tempfile')
+
 
 AUTO_HEADER = "# Automatically generated by pb2cpp\n"
 
@@ -23,6 +31,9 @@ UNDEF_STATEMENT = """
 #endif
 """
 
+PROTOC = None
+PROTOC_INCLUDE = None
+
 
 def which(pgm):
     path = os.getenv('PATH')
@@ -32,15 +43,6 @@ def which(pgm):
             return p
 
 
-PROTOC = which("protoc")
-if not PROTOC:
-    print("protoc command not found")
-    sys.exit(1)
-
-PROTOC_PREFIX = os.path.dirname(os.path.dirname(PROTOC))
-PROTOC_INCLUDE = os.path.join(PROTOC_PREFIX, "include")
-
-
 def namespace_file(fpath, package):
     """Adds / replaces package name. Simple regex parsing, may use https://github.com/ph4r05/plyprotobuf later"""
     with open(fpath) as fh:
@@ -82,9 +84,10 @@ def protoc(files, out_dir, additional_includes=(), package=None, force=False):
 
     include_dirs = set()
     include_dirs.add(PROTOC_INCLUDE)
-    include_dirs.update(additional_includes)
+    if additional_includes:
+        include_dirs.update(additional_includes)
 
-    with tempfile.TemporaryDirectory() as tmpdir_protob, tempfile.TemporaryDirectory() as tmpdir_out:
+    with TemporaryDirectory() as tmpdir_protob, TemporaryDirectory() as tmpdir_out:
         include_dirs.add(tmpdir_protob)
 
         new_files = []
@@ -125,9 +128,9 @@ def update_message_files(tmpdir_out, out_dir, force=False):
         dest_file = os.path.join(out_dir, bname)
         if not force and os.path.exists(dest_file):
             data = open(fname, 'rb').read()
-            data_hash = hashlib.sha3_256(data).digest()
+            data_hash = hashlib.sha256(data).digest()
             data_dest = open(dest_file, 'rb').read()
-            data_dest_hash = hashlib.sha3_256(data_dest).digest()
+            data_dest_hash = hashlib.sha256(data_dest).digest()
             if data_hash == data_dest_hash:
                 continue
 
@@ -163,7 +166,8 @@ def strip_leader(s, prefix):
         return s
 
 
-if __name__ == "__main__":
+def main():
+    global PROTOC, PROTOC_INCLUDE
     logging.basicConfig(level=logging.DEBUG)
 
     parser = argparse.ArgumentParser()
@@ -179,8 +183,31 @@ if __name__ == "__main__":
 
     protoc_includes = args.protoc_include or (os.environ.get("PROTOC_INCLUDE"),)
 
+    PROTOBUF_INCLUDE_DIRS = os.getenv("PROTOBUF_INCLUDE_DIRS", None)
+    PROTOBUF_PROTOC_EXECUTABLE = os.getenv("PROTOBUF_PROTOC_EXECUTABLE", None)
+
+    if PROTOBUF_PROTOC_EXECUTABLE and not os.path.exists(PROTOBUF_PROTOC_EXECUTABLE):
+        raise ValueError("PROTOBUF_PROTOC_EXECUTABLE set but not found: %s" % PROTOBUF_PROTOC_EXECUTABLE)
+
+    elif PROTOBUF_PROTOC_EXECUTABLE:
+        PROTOC = PROTOBUF_PROTOC_EXECUTABLE
+
+    else:
+        if os.name == "nt":
+            PROTOC = which("protoc.exe")
+        else:
+            PROTOC = which("protoc")
+
+    if not PROTOC:
+        raise ValueError("protoc command not found. Set PROTOBUF_PROTOC_EXECUTABLE env var to the protoc binary and optionally PROTOBUF_INCLUDE_DIRS")
+
+    PROTOC_PREFIX = os.path.dirname(os.path.dirname(PROTOC))
+    PROTOC_INCLUDE = PROTOBUF_INCLUDE_DIRS if PROTOBUF_INCLUDE_DIRS else os.path.join(PROTOC_PREFIX, "include")
+
     protoc(
         args.proto, args.out_dir, protoc_includes, package=args.namespace, force=args.force
     )
 
 
+if __name__ == "__main__":
+    main()