lib/syscall/stubgen/stubgen.py - trusty/lk/trusty - Git at Google

 #!/usr/bin/python

 # Copyright 2013-2017 Google Inc. +All rights reserved.
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files
 # (the "Software"), to deal in the Software without restriction,
 # including without limitation the rights to use, copy, modify, merge,
 # publish, distribute, sublicense, and/or sell copies of the Software,
 # and to permit persons to whom the Software is furnished to do so,
 # subject to the following conditions:
 #
 # The above copyright notice and this permission notice shall be
 # included in all copies or substantial portions of the Software.
 #
 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 # EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 # MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 # IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 # CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 # TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 # SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

 import re
 import sys
 from optparse import OptionParser

 """
 Script to generate syscall stubs from a syscall table file
 with definitions like this:

 DEF_SYSCALL(nr_syscall, syscall_name, return_type, nr_args, arg_list...)

 For e.g.,
 DEF_SYSCALL(0x3, read, 3, int fd, void *buf, int size)
 DEF_SYSCALL(0x4, write, 4, int fd, void *buf, int size)

 FUNCTION(read)
     ldr     r12, =__NR_read
     swi     #0
     bx      lr

 FUNCTION(write)
     ldr     r12, =__NR_write
     swi     #0
     bx      lr

 Another file with a enumeration of all syscalls is also generated:

 #define __NR_read  0x3
 #define __NR_write 0x4
 ...


 Only syscalls with 4 or less arguments are supported.
 """

 copyright_header = """/*
  * Copyright (c) 2012-2018 LK Trusty Authors. All Rights Reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining
  * a copy of this software and associated documentation files
  * (the "Software"), to deal in the Software without restriction,
  * including without limitation the rights to use, copy, modify, merge,
  * publish, distribute, sublicense, and/or sell copies of the Software,
  * and to permit persons to whom the Software is furnished to do so,
  * subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be
  * included in all copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
  * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 """

 autogen_header = """
 /* This file is auto-generated. !!! DO NOT EDIT !!! */

 """

 includes_header = "#include <%s>\n"

 # header file defines macros for asm
 # see include/asm.h in lk
 asm_header = "asm.h"

 class Architecture:
     def __init__(self, syscall_stub):
         self.syscall_stub = syscall_stub

 arch_dict = {
     "arm" : Architecture (
         syscall_stub = """
 .section .text.%(sys_fn)s
 FUNCTION(%(sys_fn)s)
     ldr     r12, =__NR_%(sys_fn)s
     swi     #0
     bx      lr
 """),
     "x86_64" : Architecture (
         syscall_stub = """
 FUNCTION(%(sys_fn)s)
     pushfq
     pushq %%rbp
     pushq %%rbx
     pushq %%r15
     movq $__NR_%(sys_fn)s, %%rax
     leaq .L%(sys_fn)s_sysreturn(%%rip), %%rbx
     movq %%rsp, %%rbp
     sysenter
 .L%(sys_fn)s_sysreturn:
     popq %%r15
     popq %%rbx
     popq %%rbp
     popfq
     ret
 """),
 }

 syscall_define = "#define __NR_%(sys_fn)s\t\t%(sys_nr)s\n"

 syscall_proto = "%(sys_rt)s %(sys_fn)s (%(sys_args)s);\n"

 asm_ifdef = "\n#ifndef ASSEMBLY\n"
 asm_endif = "\n#endif\n"

 beg_cdecls = "\n__BEGIN_CDECLS\n"
 end_cdecls = "\n__END_CDECLS\n"

 syscall_def = "DEF_SYSCALL"

 syscall_pat = (
     r'DEF_SYSCALL\s*\('
     r'\s*(?P<sys_nr>\d+|0x[\da-fA-F]+)\s*,'      # syscall nr
     r'\s*(?P<sys_fn>\w+)\s*,'                    # syscall name
     r'\s*(?P<sys_rt>[\w*\s]+)\s*,'               # return type
     r'\s*(?P<sys_nr_args>\d+)\s*'                # nr ags
     r'('
     r'\)\s*$|'                                   # empty arg list or
     r',\s*(?P<sys_args>[\w,*\s]+)'               # arg list
     r'\)\s*$'
     r')')

 syscall_re = re.compile(syscall_pat)


 def perror(line, err_str):
     sys.stderr.write("Error processing line %s:\n%s" % (line, err_str))


 def parse_check_def(line):
     """
     Parse a DEF_SYSCALL line and check for errors
     Returns various components from the line.
     """

     try:
         gd = syscall_re.match(line).groupdict()

         sys_nr_args = int(gd['sys_nr_args'])
         sys_args = gd['sys_args']

         # check nr args
         if sys_nr_args > 4:
             perror(line, "Only syscalls with up to 4 arguments"
                          "are supported.\n")
             return None

         if sys_nr_args > 0:
             sys_args_list = re.split(r'\s*,\s*', sys_args)

             if len(sys_args_list) > sys_nr_args:
                 perror(line, "Too many arguments supplied\n")
                 return None
             elif len(sys_args_list) < sys_nr_args:
                 perror(line, "Too few arguments supplied\n")
                 return None
         else:
             if sys_args != None:
                 perror(line, "Too many arguments supplied\n")
                 return None

             gd['sys_args'] = 'void'

         return gd

     except:
         sys.stderr.write("Exception encounterd while processing"
                          " line: %s\n" % line)
         import traceback
         traceback.print_exc()
         return None


 def process_table(table_file, std_file, stubs_file, verify, arch):
     """
     Process a syscall table and generate:
     1. A sycall stubs file
     2. A trusty_std.h header file with syscall definitions
        and function prototypes
     """
     define_lines = ""
     proto_lines = "\n"
     stub_lines = ""

     tbl = open(table_file, "r")
     for line in tbl:
         line = line.strip()

         # skip all lines that don't start with a syscall definition
         # multi-line defintions are not supported.
         if not line.startswith(syscall_def):
             continue

         params = parse_check_def(line)

         if params is None:
             sys.exit(2)

         if not verify:
             define_lines += syscall_define % params
             proto_lines += syscall_proto % params
             stub_lines += arch.syscall_stub % params


     tbl.close()

     if verify:
         return

     if std_file is not None:
         with open(std_file, "w") as std:
             std.writelines(copyright_header + autogen_header)
             std.writelines(define_lines + asm_ifdef + beg_cdecls)
             std.writelines(proto_lines + end_cdecls + asm_endif)

     if stubs_file is not None:
         with open(stubs_file, "w") as stubs:
             stubs.writelines(copyright_header + autogen_header)
             stubs.writelines(includes_header % asm_header)
             if std_file is not None:
                 stubs.writelines(includes_header % std_file)
             stubs.writelines(stub_lines)


 def main():

     usage = "usage:  %prog [options] <syscall-table>"

     op = OptionParser(usage=usage)
     op.add_option("-v", "--verify", action="store_true",
             dest="verify", default=False,
             help="Sanity check syscall table. Do not generate any files.")
     op.add_option("-d", "--std-header", type="string",
             dest="std_file", default=None,
             help="path to syscall defintions header file.")
     op.add_option("-s", "--stubs-file", type="string",
             dest="stub_file", default=None,
             help="path to syscall assembly stubs file.")
     op.add_option("-a", "--arch", type="string",
             dest="arch", default="arm",
             help="arch of stub assembly files: " + str(arch_dict.keys()))

     (opts, args) = op.parse_args()

     if len(args) == 0:
         op.print_help()
         sys.exit(1)

     if not opts.verify:
         if opts.std_file is None and opts.stub_file is None:
             op.print_help()
             sys.exit(1)

     process_table(args[0], opts.std_file, opts.stub_file, opts.verify,
             arch_dict[opts.arch])


 if __name__ == '__main__':
     main()
	#!/usr/bin/python

	# Copyright 2013-2017 Google Inc. +All rights reserved.
	#
	# Permission is hereby granted, free of charge, to any person obtaining
	# a copy of this software and associated documentation files
	# (the "Software"), to deal in the Software without restriction,
	# including without limitation the rights to use, copy, modify, merge,
	# publish, distribute, sublicense, and/or sell copies of the Software,
	# and to permit persons to whom the Software is furnished to do so,
	# subject to the following conditions:
	#
	# The above copyright notice and this permission notice shall be
	# included in all copies or substantial portions of the Software.
	#
	# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
	# IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
	# CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
	# TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
	# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

	import re
	import sys
	from optparse import OptionParser

	"""
	Script to generate syscall stubs from a syscall table file
	with definitions like this:

	DEF_SYSCALL(nr_syscall, syscall_name, return_type, nr_args, arg_list...)

	For e.g.,
	DEF_SYSCALL(0x3, read, 3, int fd, void *buf, int size)
	DEF_SYSCALL(0x4, write, 4, int fd, void *buf, int size)

	FUNCTION(read)
	ldr r12, =__NR_read
	swi #0
	bx lr

	FUNCTION(write)
	ldr r12, =__NR_write
	swi #0
	bx lr

	Another file with a enumeration of all syscalls is also generated:

	#define __NR_read 0x3
	#define __NR_write 0x4
	...


	Only syscalls with 4 or less arguments are supported.
	"""

	copyright_header = """/*
	* Copyright (c) 2012-2018 LK Trusty Authors. All Rights Reserved.
	*
	* Permission is hereby granted, free of charge, to any person obtaining
	* a copy of this software and associated documentation files
	* (the "Software"), to deal in the Software without restriction,
	* including without limitation the rights to use, copy, modify, merge,
	* publish, distribute, sublicense, and/or sell copies of the Software,
	* and to permit persons to whom the Software is furnished to do so,
	* subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be
	* included in all copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
	* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
	* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
	* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
	* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
	*/
	"""

	autogen_header = """
	/* This file is auto-generated. !!! DO NOT EDIT !!! */

	"""

	includes_header = "#include <%s>\n"

	# header file defines macros for asm
	# see include/asm.h in lk
	asm_header = "asm.h"

	class Architecture:
	def __init__(self, syscall_stub):
	self.syscall_stub = syscall_stub

	arch_dict = {
	"arm" : Architecture (
	syscall_stub = """
	.section .text.%(sys_fn)s
	FUNCTION(%(sys_fn)s)
	ldr r12, =__NR_%(sys_fn)s
	swi #0
	bx lr
	"""),
	"x86_64" : Architecture (
	syscall_stub = """
	FUNCTION(%(sys_fn)s)
	pushfq
	pushq %%rbp
	pushq %%rbx
	pushq %%r15
	movq $__NR_%(sys_fn)s, %%rax
	leaq .L%(sys_fn)s_sysreturn(%%rip), %%rbx
	movq %%rsp, %%rbp
	sysenter
	.L%(sys_fn)s_sysreturn:
	popq %%r15
	popq %%rbx
	popq %%rbp
	popfq
	ret
	"""),
	}

	syscall_define = "#define __NR_%(sys_fn)s\t\t%(sys_nr)s\n"

	syscall_proto = "%(sys_rt)s %(sys_fn)s (%(sys_args)s);\n"

	asm_ifdef = "\n#ifndef ASSEMBLY\n"
	asm_endif = "\n#endif\n"

	beg_cdecls = "\n__BEGIN_CDECLS\n"
	end_cdecls = "\n__END_CDECLS\n"

	syscall_def = "DEF_SYSCALL"

	syscall_pat = (
	r'DEF_SYSCALL\s*\('
	r'\s(?P<sys_nr>\d+\|0x[\da-fA-F]+)\s,' # syscall nr
	r'\s(?P<sys_fn>\w+)\s,' # syscall name
	r'\s(?P<sys_rt>[\w\s]+)\s*,' # return type
	r'\s(?P<sys_nr_args>\d+)\s' # nr ags
	r'('
	r'\)\s*$\|' # empty arg list or
	r',\s(?P<sys_args>[\w,\s]+)' # arg list
	r'\)\s*$'
	r')')

	syscall_re = re.compile(syscall_pat)


	def perror(line, err_str):
	sys.stderr.write("Error processing line %s:\n%s" % (line, err_str))



	def parse_check_def(line):
	"""
	Parse a DEF_SYSCALL line and check for errors
	Returns various components from the line.
	"""

	try:
	gd = syscall_re.match(line).groupdict()

	sys_nr_args = int(gd['sys_nr_args'])
	sys_args = gd['sys_args']

	# check nr args
	if sys_nr_args > 4:
	perror(line, "Only syscalls with up to 4 arguments"
	"are supported.\n")
	return None

	if sys_nr_args > 0:
	sys_args_list = re.split(r'\s,\s', sys_args)

	if len(sys_args_list) > sys_nr_args:
	perror(line, "Too many arguments supplied\n")
	return None
	elif len(sys_args_list) < sys_nr_args:
	perror(line, "Too few arguments supplied\n")
	return None
	else:
	if sys_args != None:
	perror(line, "Too many arguments supplied\n")
	return None

	gd['sys_args'] = 'void'

	return gd

	except:
	sys.stderr.write("Exception encounterd while processing"
	" line: %s\n" % line)
	import traceback
	traceback.print_exc()
	return None


	def process_table(table_file, std_file, stubs_file, verify, arch):
	"""
	Process a syscall table and generate:
	1. A sycall stubs file
	2. A trusty_std.h header file with syscall definitions
	and function prototypes
	"""
	define_lines = ""
	proto_lines = "\n"
	stub_lines = ""

	tbl = open(table_file, "r")
	for line in tbl:
	line = line.strip()

	# skip all lines that don't start with a syscall definition
	# multi-line defintions are not supported.
	if not line.startswith(syscall_def):
	continue

	params = parse_check_def(line)

	if params is None:
	sys.exit(2)

	if not verify:
	define_lines += syscall_define % params
	proto_lines += syscall_proto % params
	stub_lines += arch.syscall_stub % params


	tbl.close()

	if verify:
	return

	if std_file is not None:
	with open(std_file, "w") as std:
	std.writelines(copyright_header + autogen_header)
	std.writelines(define_lines + asm_ifdef + beg_cdecls)
	std.writelines(proto_lines + end_cdecls + asm_endif)

	if stubs_file is not None:
	with open(stubs_file, "w") as stubs:
	stubs.writelines(copyright_header + autogen_header)
	stubs.writelines(includes_header % asm_header)
	if std_file is not None:
	stubs.writelines(includes_header % std_file)
	stubs.writelines(stub_lines)


	def main():

	usage = "usage: %prog [options] <syscall-table>"

	op = OptionParser(usage=usage)
	op.add_option("-v", "--verify", action="store_true",
	dest="verify", default=False,
	help="Sanity check syscall table. Do not generate any files.")
	op.add_option("-d", "--std-header", type="string",
	dest="std_file", default=None,
	help="path to syscall defintions header file.")
	op.add_option("-s", "--stubs-file", type="string",
	dest="stub_file", default=None,
	help="path to syscall assembly stubs file.")
	op.add_option("-a", "--arch", type="string",
	dest="arch", default="arm",
	help="arch of stub assembly files: " + str(arch_dict.keys()))

	(opts, args) = op.parse_args()

	if len(args) == 0:
	op.print_help()
	sys.exit(1)

	if not opts.verify:
	if opts.std_file is None and opts.stub_file is None:
	op.print_help()
	sys.exit(1)

	process_table(args[0], opts.std_file, opts.stub_file, opts.verify,
	arch_dict[opts.arch])


	if __name__ == '__main__':
	main()