tcti/py: initial commit

Implmenet a TCTI module that will allow folks to write TCTIs in Python3.
This will allow for more crazy and complex TCTI scenarios without having
to re-write everyones stacks to use tpm2-pytss.

Example Commandline:
```bash
PYTHONPATH=$HOME tpm2_getcap --verbose --tcti=py:pytctitabrmd properties-fixed
```

Example TCTI:
For the ultimate in mind-bending: C -> Python -> C and back for
efficiency :-p.

```python3
from tpm2_pytss import TCTILdr

class MyPyTCTI(object):
    def __init__(self, args: str):
        c = args.split(":", maxsplit=1)
        print(f"PYTHON: Initializing TCTI Ldr with mod: {c[0]} args: {c[1]}")
        self._tcti = TCTILdr(c[0], c[1])

    @Property
    def magic(self):
         # Optional Method
         print("PYHTON magic")
         return 42

    def receive(self, timeout: int) -> bytes:
        print("PYTHON receive")
        return self._tcti.receive(timeout=timeout)

    def transmit(self, data:bytes):
        print("PYTHON transmit")
        self._tcti.transmit(data)

def tcti_init(args: str) -> MyPyTCTI:
    print(f"PYTHON tcti_init called with: {args}")
    return MyPyTCTI(args)
```

Signed-off-by: Bill Roberts <bill.c.roberts+gh@gmail.com>

Makefile-test.am

@@ -139,6 +139,9 @@ endif
 if ENABLE_TCTI_I2C_FTDI
 TESTS_UNIT += test/unit/tcti-i2c-ftdi
 endif
+if ENABLE_TCTI_PY
+TESTS_UNIT += test/unit/tcti-py
+endif
 if ESYS
 TESTS_UNIT += \
     test/unit/esys-context-null \
@@ -599,6 +602,15 @@ test_unit_tcti_i2c_ftdi_SOURCES = test/unit/tcti-i2c-ftdi.c \
                                   src/tss2-tcti/tcti-i2c-ftdi.c
 endif
 
+if ENABLE_TCTI_PY
+test_unit_tcti_py_CFLAGS  = $(CMOCKA_CFLAGS) $(TESTS_CFLAGS) $(PYTHON3_CFLAGS)
+test_unit_tcti_py_LDFLAGS = $(PYTHON3_LIBS) -ldl -lpthread -ltss2-mu -ltss2-esys
+test_unit_tcti_py_LDADD   = $(CMOCKA_LIBS) $(test_unit_log_LDADD)
+test_unit_tcti_py_SOURCES = test/unit/tcti-py.c \
+                            src/tss2-tcti/tcti-py.c \
+                            src/tss2-tcti/tcti-common.c
+endif
+
 test_unit_tctildr_CFLAGS = $(CMOCKA_CFLAGS) $(TESTS_CFLAGS)
 test_unit_tctildr_LDADD = $(CMOCKA_LIBS) $(libutil)
 test_unit_tctildr_LDFLAGS = -Wl,--wrap=calloc,--wrap=free \

Makefile.am

@@ -541,6 +541,28 @@ src_tss2_tcti_libtss2_tcti_i2c_ftdi_la_SOURCES  = \
     src/tss2-tcti/tcti-i2c-ftdi.h
 endif # ENABLE_TCTI_I2C_FTDI
 
+# tcti library for python implemented TCTIs
+if ENABLE_TCTI_PY
+libtss2_tcti_py = src/tss2-tcti/libtss2-tcti-py.la
+tss2_HEADERS += $(srcdir)/include/tss2/tss2_tcti_py.h
+lib_LTLIBRARIES += $(libtss2_tcti_py)
+pkgconfig_DATA += lib/tss2-tcti-py.pc
+EXTRA_DIST += lib/tss2-tcti-py.map \
+              lib/tss2-tcti-py.def
+
+src_tss2_tcti_libtss2_tcti_py_la_CFLAGS  = $(AM_CFLAGS) $(PYTHON3_CFLAGS) -Wno-deprecated-declarations
+src_tss2_tcti_libtss2_tcti_py_la_LDFLAGS  = -ldl -lpthread $(PYTHON3_LIBS)
+if HAVE_LD_VERSION_SCRIPT
+src_tss2_tcti_libtss2_tcti_py_la_LDFLAGS  += -Wl,--version-script=$(srcdir)/lib/tss2-tcti-py.map
+endif # HAVE_LD_VERSION_SCRIPT
+src_tss2_tcti_libtss2_tcti_py_la_LIBADD   = $(libutil)
+src_tss2_tcti_libtss2_tcti_py_la_SOURCES  = \
+    src/tss2-tcti/tcti-common.c \
+    src/tss2-tcti/tcti-py.c \
+    src/tss2-tcti/tcti-py.h
+endif # ENABLE_TCTI_PY
+
+
 ### TCG TSS SYS spec library ###
 libtss2_sys = src/tss2-sys/libtss2-sys.la
 tss2_HEADERS += $(srcdir)/include/tss2/tss2_sys.h
@@ -936,6 +958,7 @@ man7_MANS = \
     man/man7/tss2-tcti-spi-ftdi.7 \
     man/man7/tss2-tcti-i2c-helper.7 \
     man/man7/tss2-tcti-i2c-ftdi.7 \
+    man/man7/tss2-tcti-py.7 \
     man/man7/tss2-tctildr.7
 
 if FAPI
@@ -1033,6 +1056,7 @@ EXTRA_DIST += \
     man/tss2-tcti-spi-ftdi.7.in \
     man/tss2-tcti-i2c-helper.7.in \
     man/tss2-tcti-i2c-ftdi.7.in \
+    man/tss2-tcti-py.7.in \
     man/tss2-tctildr.7.in
 
 CLEANFILES += \

configure.ac

@@ -15,7 +15,8 @@ m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES([yes])]) #Backward compatible setti
 
 AC_CONFIG_HEADERS([config.h])
 
-AC_CONFIG_FILES([Makefile Doxyfile lib/tss2-sys.pc lib/tss2-esys.pc lib/tss2-mu.pc lib/tss2-tcti-device.pc lib/tss2-tcti-mssim.pc lib/tss2-tcti-swtpm.pc lib/tss2-tcti-pcap.pc lib/tss2-tcti-libtpms.pc lib/tss2-rc.pc lib/tss2-tctildr.pc lib/tss2-fapi.pc lib/tss2-tcti-cmd.pc lib/tss2-policy.pc lib/tss2-tcti-spi-helper.pc lib/tss2-tcti-spi-ltt2go.pc lib/tss2-tcti-spidev.pc lib/tss2-tcti-spi-ftdi.pc lib/tss2-tcti-i2c-helper.pc lib/tss2-tcti-i2c-ftdi.pc])
+AC_CONFIG_FILES([Makefile Doxyfile lib/tss2-sys.pc lib/tss2-esys.pc lib/tss2-mu.pc lib/tss2-tcti-device.pc lib/tss2-tcti-mssim.pc lib/tss2-tcti-swtpm.pc lib/tss2-tcti-pcap.pc lib/tss2-tcti-libtpms.pc lib/tss2-rc.pc lib/tss2-tctildr.pc lib/tss2-fapi.pc lib/tss2-tcti-cmd.pc lib/tss2-policy.pc lib/tss2-tcti-spi-helper.pc lib/tss2-tcti-spi-ltt2go.pc lib/tss2-tcti-spidev.pc lib/tss2-tcti-spi-ftdi.pc lib/tss2-tcti-i2c-helper.pc lib/tss2-tcti-i2c-ftdi.pc
+lib/tss2-tcti-py.pc])
 
 # propagate configure arguments to distcheck
 AC_SUBST([DISTCHECK_CONFIGURE_FLAGS],[$ac_configure_args])
@@ -390,6 +391,22 @@ AM_CONDITIONAL([ENABLE_TCTI_I2C_FTDI], [test "x$enable_tcti_i2c_ftdi" != xno])
 AS_IF([test "x$enable_tcti_i2c_ftdi" = "xyes"],
     AC_DEFINE([TCTI_I2C_FTDI],[1], [TCTI FOR USB BASED ACCESS TO I2C BASED TPM OVER THE FTDI MPSSE USB TO I2C BRIDGE]))
 
+AC_ARG_ENABLE([tcti-py],
+            [AS_HELP_STRING([--enable-tcti-py],
+                            [build the tcti-py module])],,
+            [enable_tcti_py=no])
+
+AM_CONDITIONAL([ENABLE_TCTI_PY], [test "x$enable_tcti_py" != xno])
+AS_IF([test "x$enable_tcti_py" = "xyes"],
+	[AC_DEFINE([TCTI_PY],[1], [TCTI FOR PYTHON3 BASED TCTI IMPLEMENTATIONS])
+	    PKG_CHECK_MODULES([PYTHON3], [python3])
+	    PYTHON3_LIBS=$(python3-config --ldflags --embed)
+])
+
+# If building tcti-py with unit tests you need ESAPI
+AS_IF([test "x$enable_tcti_py" = "xyes" -a "x$enable_unit" = "xyes" -a "x$enable_esys" != "xyes" ],
+	[AC_MSG_ERROR(["Must enable esys with tss2-py-tcti])])
+
 AC_ARG_ENABLE([tcti-fuzzing],
             [AS_HELP_STRING([--enable-tcti-fuzzing],
                             [build the tcti-fuzzing module])],,
@@ -754,4 +771,5 @@ AC_MSG_RESULT([
     tcti_spidev         $enable_tcti_spidev
     tcti_spi_ftdi       $enable_tcti_spi_ftdi
     tcti_i2c_ftdi       $enable_tcti_i2c_ftdi
+    tcti_py             $enable_tcti_py
 ])

doc/tcti-py.md

@@ -0,0 +1,63 @@
+# Python TCTI (py-tcti)
+
+The Python TCTI can be used to write TCTI modules in Python3. This allows a user to make use of the
+robust language features and modules that are available in Python3.
+
+## Invoking the Python TCTI
+
+Like implementing any TCTI, one can follow the friendly conventions or provide the full path of the shared
+object to `Tss2_TCTILdr_Initialize` or one can instantiate the TCTI directly with `TSS2_TCTI_Py_Initialize`.
+
+One needs to specify a module name (the name of a python file) and optionally arguments to pass to an init
+function in that module. The signature of this method is: `def tcti_init(args: str) -> Object` and the
+args string passed in is the args option appended on the configuration string.
+
+One possible way to use it with the command line tools is via the `--tcti=py:<modname>:<args>`. For
+example:
+```bash
+# Python3 file pytcti.py exists in $HOME
+PYTHONPATH=$HOME tpm2_getcap --tcti=py:pytcti properties-fixed
+```
+
+## Example Python TCTI
+
+The below sample code TCTI just uses tpm2-pytss package to call TCTILdr with whatever
+argument string is provided. It just showcases full path delivery of commands. To invoke
+the example code below, assuming that the python file is named pytcti.py and you want
+to connect to tpm2-abrmd resource manager do:
+```bash
+PYTHONPATH=$HOME tpm2_getcap --tcti=py:pytcti:tabrmd properties-fixed
+```
+
+```python3
+# SPDX-License-Identifier: BSD-2-Clause
+from tpm2_pytss import TCTILdr
+
+
+class MyPyTCTI(object):
+    def __init__(self, args: str):
+        c = args.split(":", maxsplit=1)
+        mod = c[0]
+        args = c[1] if len(c) > 1 else "None"
+        print(f"PYTHON: Initializing TCTI Ldr with mod: {mod} args: {args}")
+        self._tcti = TCTILdr(mod, args)
+
+    @property
+    def magic(self):
+        # Optional Method
+        print("PYTHON magic")
+        return 42
+
+    def receive(self, timeout: int) -> bytes:
+        print("PYTHON receive")
+        return self._tcti.receive(timeout=timeout)
+
+    def transmit(self, data: bytes):
+        print("PYTHON transmit")
+        self._tcti.transmit(data)
+
+
+def tcti_init(args: str) -> MyPyTCTI:
+    print(f"PYTHON tcti_init called with: {args}")
+    return MyPyTCTI(args)
+```

include/tss2/tss2_tcti_py.h

@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+#ifndef TSS2_TCTI_CMD_H
+#define TSS2_TCTI_CMD_H
+
+#include "tss2_tcti.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+TSS2_RC Tss2_Tcti_Py_Init (
+    TSS2_TCTI_CONTEXT *tctiContext,
+    size_t *size,
+    const char *conf);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* TSS2_TCTI_CMD_H */

lib/tss2-tcti-pc.def

@@ -0,0 +1,4 @@
+LIBRARY tss2-tcti-py
+EXPORTS
+    Tss2_Tcti_Info
+    Tss2_Tcti_Py_Init

lib/tss2-tcti-pc.map

@@ -0,0 +1,7 @@
+{
+    global:
+        Tss2_Tcti_Info;
+        Tss2_Tcti_Py_Init;
+    local:
+        *;
+};

lib/tss2-tcti-py.def

@@ -0,0 +1,4 @@
+LIBRARY tss2-tcti-py
+EXPORTS
+    Tss2_Tcti_Info
+    Tss2_Tcti_Py_Init

lib/tss2-tcti-py.map

@@ -0,0 +1,7 @@
+{
+    global:
+        Tss2_Tcti_Info;
+        Tss2_Tcti_Py_Init;
+    local:
+        *;
+};

lib/tss2-tcti-py.pc.in

@@ -0,0 +1,11 @@
+prefix=@prefix@
+exec_prefix=@exec_prefix@
+libdir=@libdir@
+includedir=@includedir@
+
+Name: tss2-tcti-py
+Description: TCTI library for implementing TCTIs in Python3.
+URL: https://github.com/tpm2-software/tpm2-tss
+Version: @VERSION@
+Cflags: -I${includedir} -I${includedir}/tss2
+Libs: -ltss2-py -L${libdir}

man/tss2-tcti-py.7.in

@@ -0,0 +1,14 @@
+.\" Process this file with
+.\" groff -man -Tascii foo.1
+.\"
+.TH TCTI-PY 7 "JANUARY 2023" "TPM2 Software Stack"
+.SH NAME
+tcti-py \- Launch Python3 TPM2 TCTIs
+.SH SYNOPSIS
+Write a TCTI in Python3.
+.SH DESCRIPTION
+tcti-py is a library that allows creating TCTIs in Python3 by implementing a
+a TCTI interface in Python. More complete documentation can be found by
+visiting this URL: https://github.com/tpm2-software/tpm2-tss/tree/master/doc/tcti-py.md
+
+It is related to the TPM Command Transmission Interface Specification\*(rq specification.