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