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Elixir Cross Referencer

#!/usr/bin/env python
# SPDX-License-Identifier: BSD-2-Clause
#
# Copyright (c) 2017, Linaro Limited
#


import argparse
import glob
import os
import re
import subprocess
import sys

TA_UUID_RE = re.compile(r'Status of TA (?P<uuid>[0-9a-f\-]+)')
TA_INFO_RE = re.compile('  arch: (?P<arch>\w+)  '
                        'load address: (?P<load_addr>0x[0-9a-f]+)')
CALL_STACK_RE = re.compile('Call stack:')

# This gets the address from lines looking like this:
# E/TC:0  0x001044a8
STACK_ADDR_RE = re.compile(r'[UEIDFM]/T[AC]:.*(?P<addr>0x[0-9a-f]+)')
ABORT_ADDR_RE = re.compile('-abort at address (?P<addr>0x[0-9a-f]+)')
REGION_RE = re.compile('region [0-9]+: va (?P<addr>0x[0-9a-f]+) '
                       'pa 0x[0-9a-f]+ size (?P<size>0x[0-9a-f]+)')

epilog = '''
This scripts reads an OP-TEE abort or panic message from stdin and adds debug
information to the output, such as '<function> at <file>:<line>' next to each
address in the call stack. Any message generated by OP-TEE and containing a
call stack can in principle be processed by this script. This currently
includes aborts and panics from the TEE core as well as from any TA.
The paths provided on the command line are used to locate the appropriate ELF
binary (tee.elf or Trusted Application). The GNU binutils (addr2line, objdump,
nm) are used to extract the debug info.

OP-TEE abort and panic messages are sent to the secure console. They look like
the following:

  E/TC:0 User TA data-abort at address 0xffffdecd (alignment fault)
  ...
  E/TC:0 Call stack:
  E/TC:0  0x4000549e
  E/TC:0  0x40001f4b
  E/TC:0  0x4000273f
  E/TC:0  0x40005da7

Inspired by a script of the same name by the Chromium project.

Sample usage:

  $ scripts/symbolize.py -d out/arm-plat-hikey/core -d ../optee_test/out/ta/*
  <paste whole dump here>
  ^D
'''

def get_args():
    parser = argparse.ArgumentParser(
                formatter_class=argparse.RawDescriptionHelpFormatter,
                description='Symbolizes OP-TEE abort dumps',
                epilog=epilog)
    parser.add_argument('-d', '--dir', action='append', nargs='+',
        help='Search for ELF file in DIR. tee.elf is needed to decode '
             'a TEE Core or pseudo-TA abort, while <TA_uuid>.elf is required '
             'if a user-mode TA has crashed. For convenience, ELF files '
             'may also be given.')
    parser.add_argument('-s', '--strip_path', nargs='?',
        help='Strip STRIP_PATH from file paths (default: current directory, '
             'use -s with no argument to show full paths)',
        default=os.getcwd())

    return parser.parse_args()

class Symbolizer(object):
    def __init__(self, out, dirs, strip_path):
        self._out = out
        self._dirs = dirs
        self._strip_path = strip_path
        self._addr2line = None
        self._bin = 'tee.elf'
        self.reset()

    def get_elf(self, elf_or_uuid):
        if not elf_or_uuid.endswith('.elf'):
            elf_or_uuid += '.elf'
        for d in self._dirs:
            if d.endswith(elf_or_uuid) and os.path.isfile(d):
                return d
            elf = glob.glob(d + '/' + elf_or_uuid)
            if elf:
                return elf[0]

    def set_arch(self):
        if self._arch:
            return
        if self._bin:
            p = subprocess.Popen([ 'file', self.get_elf(self._bin) ],
                                 stdout=subprocess.PIPE)
            output = p.stdout.readlines()
            p.terminate()
            if 'ARM aarch64,' in output[0]:
                self._arch = 'aarch64-linux-gnu-'
            elif 'ARM,' in output[0]:
                self._arch = 'arm-linux-gnueabihf-'

    def arch_prefix(self, cmd):
        self.set_arch()
        return self._arch + cmd

    def spawn_addr2line(self):
        if not self._addr2line:
            elf = self.get_elf(self._bin)
            if not elf:
                return
            cmd = self.arch_prefix('addr2line')
            if not cmd:
                return
            self._addr2line = subprocess.Popen([cmd, '-f', '-p', '-e', elf],
                                                stdin = subprocess.PIPE,
                                                stdout = subprocess.PIPE)

    def subtract_load_addr(self, addr):
        offs = self._load_addr
        if int(offs, 16) > int(addr, 16):
            return ''
        return '0x{:x}'.format(int(addr, 16) - int(offs, 16))

    def resolve(self, addr):
        reladdr = self.subtract_load_addr(addr)
        self.spawn_addr2line()
        if not reladdr or not self._addr2line:
            return '???'
        try:
            print >> self._addr2line.stdin, reladdr
            ret = self._addr2line.stdout.readline().rstrip('\n')
        except IOError:
            ret = '!!!'
        return ret

    def symbol_plus_offset(self, addr):
        ret = ''
        prevsize = 0
        reladdr = self.subtract_load_addr(addr)
        elf = self.get_elf(self._bin)
        cmd = self.arch_prefix('nm')
        if not reladdr or not elf or not cmd:
            return ''
        ireladdr = int(reladdr, 16)
        nm = subprocess.Popen([cmd, '--numeric-sort', '--print-size', elf],
                               stdin = subprocess.PIPE,
                               stdout = subprocess.PIPE)
        for line in iter(nm.stdout.readline, ''):
            try:
                addr, size, _, name = line.split()
            except:
                # Size is missing
                addr, _, name = line.split()
                size = '0'
            iaddr = int(addr, 16)
            isize = int(size, 16)
            if iaddr == ireladdr:
                ret = name
                break
            if iaddr < ireladdr and iaddr + isize >= ireladdr:
                offs = ireladdr - iaddr
                ret = name + '+' + str(offs)
                break
            if iaddr > ireladdr and prevsize == 0:
                offs = iaddr + ireladdr
                ret = prevname + '+' + str(offs)
                break
            prevsize = size
            prevname = name
        nm.terminate()
        return ret

    def section_plus_offset(self, addr):
        ret = ''
        reladdr = self.subtract_load_addr(addr)
        elf = self.get_elf(self._bin)
        cmd = self.arch_prefix('objdump')
        if not reladdr or not elf or not cmd:
            return ''
        iaddr = int(reladdr, 16)
        objdump = subprocess.Popen([cmd, '--section-headers', elf],
                                    stdin = subprocess.PIPE,
                                    stdout = subprocess.PIPE)
        for line in iter(objdump.stdout.readline, ''):
            try:
                idx, name, size, vma, lma, offs, algn = line.split()
            except:
                continue;
            ivma = int(vma, 16)
            isize = int(size, 16)
            if ivma == iaddr:
                ret = name
                break
            if ivma < iaddr and ivma + isize >= iaddr:
                offs = iaddr - ivma
                ret = name + '+' + str(offs)
                break
        objdump.terminate()
        return ret

    def process_abort(self, line):
        ret = ''
        match = re.search(ABORT_ADDR_RE, line)
        addr = match.group('addr')
        pre = match.start('addr')
        post = match.end('addr')
        sym = self.symbol_plus_offset(addr)
        sec = self.section_plus_offset(addr)
        if sym or sec:
            ret += line[:pre]
            ret += addr
            if sym:
                ret += ' ' + sym
            if sec:
                ret += ' ' + sec
            ret += line[post:]
        return ret

    # Return all ELF sections with the ALLOC flag
    def read_sections(self):
        if self._sections:
            return
        elf = self.get_elf(self._bin)
        cmd = self.arch_prefix('objdump')
        if not elf or not cmd:
            return
        objdump = subprocess.Popen([cmd, '--section-headers', elf],
                                    stdin = subprocess.PIPE,
                                    stdout = subprocess.PIPE)
        for line in iter(objdump.stdout.readline, ''):
            try:
                _, name, size, vma, _, _, _ = line.split()
            except:
                if 'ALLOC' in line:
                    self._sections.append([name, int(vma, 16), int(size, 16)])

    def overlaps(self, section, addr, size):
        sec_addr = section[1]
        sec_size = section[2]
        if not size or not sec_size:
            return False
        return (addr <= (sec_addr + sec_size - 1)) and ((addr + size - 1) >= sec_addr)

    def sections_in_region(self, addr, size):
        ret = ''
        addr = self.subtract_load_addr(addr)
        if not addr:
            return ''
        iaddr = int(addr, 16)
        isize = int(size, 16)
        self.read_sections()
        for s in self._sections:
            if self.overlaps(s, iaddr, isize):
                ret += ' ' + s[0]
        return ret

    def reset(self):
        self._call_stack_found = False
        self._load_addr = '0'
        if self._addr2line:
            self._addr2line.terminate()
            self._addr2line = None
        self._arch = None
        self._saved_abort_line = ''
        self._sections = []
        self._bin = "tee.elf"

    def write(self, line):
            if self._call_stack_found:
                match = re.search(STACK_ADDR_RE, line)
                if match:
                    addr = match.group('addr')
                    pre = match.start('addr')
                    post = match.end('addr')
                    self._out.write(line[:pre])
                    self._out.write(addr)
                    res = self.resolve(addr)
                    if self._strip_path:
                        res = re.sub(re.escape(self._strip_path) + '/*', '',
                              res)
                    self._out.write(' ' + res)
                    self._out.write(line[post:])
                    return
                else:
                    self.reset()
            match = re.search(REGION_RE, line)
            if match:
                addr = match.group('addr')
                size = match.group('size')
                self._out.write(line.strip() +
                                self.sections_in_region(addr, size) + '\n');
                return
            match = re.search(CALL_STACK_RE, line)
            if match:
                self._call_stack_found = True
                # Here is a good place to resolve the abort address because we
                # have all the information we need
                if self._saved_abort_line:
                    self._out.write(self.process_abort(self._saved_abort_line))
            match = re.search(TA_UUID_RE, line)
            if match:
                self._bin = match.group('uuid')
            match = re.search(TA_INFO_RE, line)
            if match:
                self._load_addr = match.group('load_addr')
            match = re.search(ABORT_ADDR_RE, line)
            if match:
                self.reset()
                # At this point the arch and TA load address are unknown.
                # Save the line so We can translate the abort address later.
                self._saved_abort_line = line
            self._out.write(line)

    def flush(self):
        self._out.flush()

def main():
    args = get_args()
    if args.dir:
        # Flatten list in case -d is used several times *and* with multiple
        # arguments
        args.dirs = [item for sublist in args.dir for item in sublist]
    else:
        args.dirs = []
    symbolizer = Symbolizer(sys.stdout, args.dirs, args.strip_path)

    for line in sys.stdin:
        symbolizer.write(line)
    symbolizer.flush()

if __name__ == "__main__":
    main()