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1#!/usr/bin/env python
2
3import struct
4import sys
5import StringIO
6
7import common_dump
8
9class Reader:
10    def __init__(self, path):
11        if path == "-":
12            # Snarf all the data so we can seek.
13            self.file = StringIO.StringIO(sys.stdin.read())
14        else:
15            self.file = open(path, "rb")
16        self.isLSB = None
17        self.is64Bit = None
18
19    def seek(self, pos):
20        self.file.seek(pos)
21
22    def read(self, N):
23        data = self.file.read(N)
24        if len(data) != N:
25            raise ValueError, "Out of data!"
26        return data
27
28    def read8(self):
29        return ord(self.read(1))
30
31    def read16(self):
32        return struct.unpack('><'[self.isLSB] + 'H', self.read(2))[0]
33
34    def read32(self):
35        return struct.unpack('><'[self.isLSB] + 'I', self.read(4))[0]
36
37    def read32S(self):
38        return struct.unpack('><'[self.isLSB] + 'i', self.read(4))[0]
39
40    def read64(self):
41        return struct.unpack('><'[self.isLSB] + 'Q', self.read(8))[0]
42
43    def read64S(self):
44        return struct.unpack('><'[self.isLSB] + 'q', self.read(8))[0]
45
46    def readWord(self):
47        if self.is64Bit:
48            return self.read64()
49        else:
50            return self.read32()
51
52    def readWordS(self):
53        if self.is64Bit:
54            return self.read64S()
55        else:
56            return self.read32S()
57
58class StringTable:
59    def __init__(self, strings):
60       self.string_table = strings
61
62    def __getitem__(self, index):
63       end = self.string_table.index('\x00', index)
64       return self.string_table[index:end]
65
66class Section:
67    def __init__(self, f):
68        self.sh_name = f.read32()
69        self.sh_type = f.read32()
70        self.sh_flags = f.readWord()
71        self.sh_addr = f.readWord()
72        self.sh_offset = f.readWord()
73        self.sh_size = f.readWord()
74        self.sh_link = f.read32()
75        self.sh_info = f.read32()
76        self.sh_addralign = f.readWord()
77        self.sh_entsize = f.readWord()
78
79    def dump(self, shstrtab, f, strtab, dumpdata):
80        print "  (('sh_name', %s)" % common_dump.HexDump(self.sh_name), "# %r" % shstrtab[self.sh_name]
81        print "   ('sh_type', %s)" % common_dump.HexDump(self.sh_type)
82        print "   ('sh_flags', %s)" % common_dump.HexDump(self.sh_flags)
83        print "   ('sh_addr', %s)" % common_dump.HexDump(self.sh_addr)
84        print "   ('sh_offset', %s)" % common_dump.HexDump(self.sh_offset)
85        print "   ('sh_size', %s)" % common_dump.HexDump(self.sh_size)
86        print "   ('sh_link', %s)" % common_dump.HexDump(self.sh_link)
87        print "   ('sh_info', %s)" % common_dump.HexDump(self.sh_info)
88        print "   ('sh_addralign', %s)" % common_dump.HexDump(self.sh_addralign)
89        print "   ('sh_entsize', %s)" % common_dump.HexDump(self.sh_entsize)
90        if self.sh_type == 2: # SHT_SYMTAB
91            print "   ('_symbols', ["
92            dumpSymtab(f, self, strtab)
93            print "   ])"
94        elif self.sh_type == 4 or self.sh_type == 9: # SHT_RELA / SHT_REL
95            print "   ('_relocations', ["
96            dumpRel(f, self, self.sh_type == 4)
97            print "   ])"
98        elif dumpdata:
99            f.seek(self.sh_offset)
100            if self.sh_type != 8: # != SHT_NOBITS
101                data = f.read(self.sh_size)
102                print "   ('_section_data', '%s')" % common_dump.dataToHex(data)
103            else:
104                print "   ('_section_data', '')"
105        print "  ),"
106
107def dumpSymtab(f, section, strtab):
108    entries = section.sh_size // section.sh_entsize
109
110    for index in range(entries):
111        f.seek(section.sh_offset + index * section.sh_entsize)
112        print "    # Symbol %s" % common_dump.HexDump(index)
113        name = f.read32()
114        print "    (('st_name', %s)" % common_dump.HexDump(name), "# %r" % strtab[name]
115        if not f.is64Bit:
116            print "     ('st_value', %s)" % common_dump.HexDump(f.read32())
117            print "     ('st_size', %s)" % common_dump.HexDump(f.read32())
118        st_info = f.read8()
119        print "     ('st_bind', %s)" % common_dump.HexDump((st_info >> 4))
120        print "     ('st_type', %s)" % common_dump.HexDump((st_info & 0xf))
121        print "     ('st_other', %s)" % common_dump.HexDump(f.read8())
122        print "     ('st_shndx', %s)" % common_dump.HexDump(f.read16())
123        if f.is64Bit:
124            print "     ('st_value', %s)" % common_dump.HexDump(f.read64(), 64)
125            print "     ('st_size', %s)" % common_dump.HexDump(f.read64(), 64)
126        print "    ),"
127
128def dumpRel(f, section, dumprela = False):
129    entries = section.sh_size // section.sh_entsize
130
131    for index in range(entries):
132        f.seek(section.sh_offset + index * section.sh_entsize)
133        print "    # Relocation %s" % common_dump.HexDump(index)
134        print "    (('r_offset', %s)" % common_dump.HexDump(f.readWord())
135        r_info = f.readWord()
136        if f.is64Bit:
137            print "     ('r_sym', %s)" % common_dump.HexDump((r_info >> 32))
138            print "     ('r_type', %s)" % common_dump.HexDump((r_info & 0xffffffff))
139        else:
140            print "     ('r_sym', %s)" % common_dump.HexDump((r_info >> 8))
141            print "     ('r_type', %s)" % common_dump.HexDump((r_info & 0xff))
142        if dumprela:
143            print "     ('r_addend', %s)" % common_dump.HexDump(f.readWordS())
144        print "    ),"
145
146def dumpELF(path, opts):
147    f = Reader(path)
148
149    magic = f.read(4)
150    assert magic == '\x7FELF'
151
152    fileclass = f.read8()
153    if fileclass == 1: # ELFCLASS32
154        f.is64Bit = False
155    elif fileclass == 2: # ELFCLASS64
156        f.is64Bit = True
157    else:
158        raise ValueError, "Unknown file class %s" % common_dump.HexDump(fileclass)
159    print "('e_indent[EI_CLASS]', %s)" % common_dump.HexDump(fileclass)
160
161    byteordering = f.read8()
162    if byteordering == 1: # ELFDATA2LSB
163        f.isLSB = True
164    elif byteordering == 2: # ELFDATA2MSB
165        f.isLSB = False
166    else:
167        raise ValueError, "Unknown byte ordering %s" % common_dump.HexDump(byteordering)
168    print "('e_indent[EI_DATA]', %s)" % common_dump.HexDump(byteordering)
169
170    print "('e_indent[EI_VERSION]', %s)" % common_dump.HexDump(f.read8())
171    print "('e_indent[EI_OSABI]', %s)" % common_dump.HexDump(f.read8())
172    print "('e_indent[EI_ABIVERSION]', %s)" % common_dump.HexDump(f.read8())
173
174    f.seek(16) # Seek to end of e_ident.
175
176    print "('e_type', %s)" % common_dump.HexDump(f.read16())
177    print "('e_machine', %s)" % common_dump.HexDump(f.read16())
178    print "('e_version', %s)" % common_dump.HexDump(f.read32())
179    print "('e_entry', %s)" % common_dump.HexDump(f.readWord())
180    print "('e_phoff', %s)" % common_dump.HexDump(f.readWord())
181    e_shoff = f.readWord()
182    print "('e_shoff', %s)" % common_dump.HexDump(e_shoff)
183    print "('e_flags', %s)" % common_dump.HexDump(f.read32())
184    print "('e_ehsize', %s)" % common_dump.HexDump(f.read16())
185    print "('e_phentsize', %s)" % common_dump.HexDump(f.read16())
186    print "('e_phnum', %s)" % common_dump.HexDump(f.read16())
187    e_shentsize = f.read16()
188    print "('e_shentsize', %s)" % common_dump.HexDump(e_shentsize)
189    e_shnum = f.read16()
190    print "('e_shnum', %s)" % common_dump.HexDump(e_shnum)
191    e_shstrndx = f.read16()
192    print "('e_shstrndx', %s)" % common_dump.HexDump(e_shstrndx)
193
194    # Read all section headers
195    sections = []
196    for index in range(e_shnum):
197        f.seek(e_shoff + index * e_shentsize)
198        s = Section(f)
199        sections.append(s)
200
201    # Read .shstrtab so we can resolve section names
202    f.seek(sections[e_shstrndx].sh_offset)
203    shstrtab = StringTable(f.read(sections[e_shstrndx].sh_size))
204
205    # Get the symbol string table
206    strtab = None
207    for section in sections:
208        if shstrtab[section.sh_name] == ".strtab":
209            f.seek(section.sh_offset)
210            strtab = StringTable(f.read(section.sh_size))
211            break
212
213    print "('_sections', ["
214    for index in range(e_shnum):
215        print "  # Section %s" % common_dump.HexDump(index)
216        sections[index].dump(shstrtab, f, strtab, opts.dumpSectionData)
217    print "])"
218
219if __name__ == "__main__":
220    from optparse import OptionParser, OptionGroup
221    parser = OptionParser("usage: %prog [options] {files}")
222    parser.add_option("", "--dump-section-data", dest="dumpSectionData",
223                      help="Dump the contents of sections",
224                      action="store_true", default=False)
225    (opts, args) = parser.parse_args()
226
227    if not args:
228        args.append('-')
229
230    for arg in args:
231        dumpELF(arg, opts)
232