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        self.isN64 = False
19
20    def seek(self, pos):
21        self.file.seek(pos)
22
23    def read(self, N):
24        data = self.file.read(N)
25        if len(data) != N:
26            raise ValueError, "Out of data!"
27        return data
28
29    def read8(self):
30        return (ord(self.read(1)), 8)
31
32    def read16(self):
33        return (struct.unpack('><'[self.isLSB] + 'H', self.read(2))[0], 16)
34
35    def read32(self):
36        return (struct.unpack('><'[self.isLSB] + 'I', self.read(4))[0], 32)
37
38    def read64(self):
39        return (struct.unpack('><'[self.isLSB] + 'Q', self.read(8))[0], 64)
40
41    def readWord(self):
42        if self.is64Bit:
43            return self.read64()
44        else:
45            return self.read32()
46
47class StringTable:
48    def __init__(self, strings):
49       self.string_table = strings
50
51    def __getitem__(self, index):
52       end = self.string_table.index('\x00', index)
53       return self.string_table[index:end]
54
55class Section:
56    def __init__(self, f):
57        self.sh_name = f.read32()
58        self.sh_type = f.read32()
59        self.sh_flags = f.readWord()
60        self.sh_addr = f.readWord()
61        self.sh_offset = f.readWord()
62        self.sh_size = f.readWord()
63        self.sh_link = f.read32()
64        self.sh_info = f.read32()
65        self.sh_addralign = f.readWord()
66        self.sh_entsize = f.readWord()
67
68    def dump(self, shstrtab, f, strtab, dumpdata):
69        print "  (('sh_name', %s)" % common_dump.HexDump(self.sh_name), "# %r" % shstrtab[self.sh_name[0]]
70        print "   ('sh_type', %s)" % common_dump.HexDump(self.sh_type)
71        print "   ('sh_flags', %s)" % common_dump.HexDump(self.sh_flags)
72        print "   ('sh_addr', %s)" % common_dump.HexDump(self.sh_addr)
73        print "   ('sh_offset', %s)" % common_dump.HexDump(self.sh_offset)
74        print "   ('sh_size', %s)" % common_dump.HexDump(self.sh_size)
75        print "   ('sh_link', %s)" % common_dump.HexDump(self.sh_link)
76        print "   ('sh_info', %s)" % common_dump.HexDump(self.sh_info)
77        print "   ('sh_addralign', %s)" % common_dump.HexDump(self.sh_addralign)
78        print "   ('sh_entsize', %s)" % common_dump.HexDump(self.sh_entsize)
79        if self.sh_type[0] == 2: # SHT_SYMTAB
80            print "   ('_symbols', ["
81            dumpSymtab(f, self, strtab)
82            print "   ])"
83        elif self.sh_type[0] == 4 or self.sh_type[0] == 9: # SHT_RELA / SHT_REL
84            print "   ('_relocations', ["
85            dumpRel(f, self, self.sh_type[0] == 4)
86            print "   ])"
87        elif dumpdata:
88            f.seek(self.sh_offset[0])
89            if self.sh_type != 8: # != SHT_NOBITS
90                data = f.read(self.sh_size[0])
91                print "   ('_section_data', '%s')" % common_dump.dataToHex(data)
92            else:
93                print "   ('_section_data', '')" 
94        print "  ),"
95
96def dumpSymtab(f, section, strtab):
97    entries = section.sh_size[0] // section.sh_entsize[0]
98
99    for index in range(entries):
100        f.seek(section.sh_offset[0] + index * section.sh_entsize[0])
101        print "    # Symbol %s" % index
102        name = f.read32()
103        print "    (('st_name', %s)" % common_dump.HexDump(name), "# %r" % strtab[name[0]]
104        if not f.is64Bit:
105            print "     ('st_value', %s)" % common_dump.HexDump(f.read32())
106            print "     ('st_size', %s)" % common_dump.HexDump(f.read32())
107        st_info = f.read8()[0]
108        st_bind = (st_info >> 4, 4)
109        st_type = (st_info & 0xf, 4)
110        print "     ('st_bind', %s)" % common_dump.HexDump(st_bind)
111        print "     ('st_type', %s)" % common_dump.HexDump(st_type)
112        print "     ('st_other', %s)" % common_dump.HexDump(f.read8())
113        print "     ('st_shndx', %s)" % common_dump.HexDump(f.read16())
114        if f.is64Bit:
115            print "     ('st_value', %s)" % common_dump.HexDump(f.read64())
116            print "     ('st_size', %s)" % common_dump.HexDump(f.read64())
117        print "    ),"
118
119def dumpRel(f, section, dumprela = False):
120    entries = section.sh_size[0] // section.sh_entsize[0]
121
122    for index in range(entries):
123        f.seek(section.sh_offset[0] + index * section.sh_entsize[0])
124        print "    # Relocation %s" % index
125        print "    (('r_offset', %s)" % common_dump.HexDump(f.readWord())
126
127        if f.isN64:
128            r_sym =   f.read32()
129            r_ssym =  f.read8()
130            r_type3 = f.read8()
131            r_type2 = f.read8()
132            r_type =  f.read8()
133            print "     ('r_sym', %s)" % common_dump.HexDump(r_sym)
134            print "     ('r_ssym', %s)" % common_dump.HexDump(r_ssym)
135            print "     ('r_type3', %s)" % common_dump.HexDump(r_type3)
136            print "     ('r_type2', %s)" % common_dump.HexDump(r_type2)
137            print "     ('r_type', %s)" % common_dump.HexDump(r_type)
138        else:
139            r_info = f.readWord()[0]
140            if f.is64Bit:
141                r_sym = (r_info >> 32, 32)
142                r_type = (r_info & 0xffffffff, 32)
143            else:
144                r_sym = (r_info >> 8, 24)
145                r_type = (r_info & 0xff, 8)
146            print "     ('r_sym', %s)" % common_dump.HexDump(r_sym)
147            print "     ('r_type', %s)" % common_dump.HexDump(r_type)
148        if dumprela:
149            print "     ('r_addend', %s)" % common_dump.HexDump(f.readWord())
150        print "    ),"
151
152def dumpELF(path, opts):
153    f = Reader(path)
154
155    magic = f.read(4)
156    assert magic == '\x7FELF'
157
158    fileclass = f.read8()
159    if fileclass[0] == 1: # ELFCLASS32
160        f.is64Bit = False
161    elif fileclass[0] == 2: # ELFCLASS64
162        f.is64Bit = True
163    else:
164        raise ValueError, "Unknown file class %s" % common_dump.HexDump(fileclass)
165    print "('e_indent[EI_CLASS]', %s)" % common_dump.HexDump(fileclass)
166
167    byteordering = f.read8()
168    if byteordering[0] == 1: # ELFDATA2LSB
169        f.isLSB = True
170    elif byteordering[0] == 2: # ELFDATA2MSB
171        f.isLSB = False
172    else:
173        raise ValueError, "Unknown byte ordering %s" % common_dump.HexDump(byteordering)
174    print "('e_indent[EI_DATA]', %s)" % common_dump.HexDump(byteordering)
175
176    print "('e_indent[EI_VERSION]', %s)" % common_dump.HexDump(f.read8())
177    print "('e_indent[EI_OSABI]', %s)" % common_dump.HexDump(f.read8())
178    print "('e_indent[EI_ABIVERSION]', %s)" % common_dump.HexDump(f.read8())
179
180    f.seek(16) # Seek to end of e_ident.
181
182    print "('e_type', %s)" % common_dump.HexDump(f.read16())
183
184    # Does any other architecture use N64?
185    e_machine = f.read16()
186    if e_machine[0] == 0x0008 and f.is64Bit: # EM_MIPS && 64 bit
187        f.isN64 = True 
188    
189    print "('e_machine', %s)" % common_dump.HexDump(e_machine)
190    print "('e_version', %s)" % common_dump.HexDump(f.read32())
191    print "('e_entry', %s)" % common_dump.HexDump(f.readWord())
192    print "('e_phoff', %s)" % common_dump.HexDump(f.readWord())
193    e_shoff = f.readWord()
194    print "('e_shoff', %s)" % common_dump.HexDump(e_shoff)
195    print "('e_flags', %s)" % common_dump.HexDump(f.read32())
196    print "('e_ehsize', %s)" % common_dump.HexDump(f.read16())
197    print "('e_phentsize', %s)" % common_dump.HexDump(f.read16())
198    print "('e_phnum', %s)" % common_dump.HexDump(f.read16())
199    e_shentsize = f.read16()
200    print "('e_shentsize', %s)" % common_dump.HexDump(e_shentsize)
201    e_shnum = f.read16()
202    print "('e_shnum', %s)" % common_dump.HexDump(e_shnum)
203    e_shstrndx = f.read16()
204    print "('e_shstrndx', %s)" % common_dump.HexDump(e_shstrndx)
205
206    # Read all section headers
207    sections = []
208    for index in range(e_shnum[0]):
209        f.seek(e_shoff[0] + index * e_shentsize[0])
210        s = Section(f)
211        sections.append(s)
212
213    # Read .shstrtab so we can resolve section names
214    f.seek(sections[e_shstrndx[0]].sh_offset[0])
215    shstrtab = StringTable(f.read(sections[e_shstrndx[0]].sh_size[0]))
216
217    # Get the symbol string table
218    strtab = None
219    for section in sections:
220        if shstrtab[section.sh_name[0]] == ".strtab":
221            f.seek(section.sh_offset[0])
222            strtab = StringTable(f.read(section.sh_size[0]))
223            break
224
225    print "('_sections', ["
226    for index in range(e_shnum[0]):
227        print "  # Section %s" % index
228        sections[index].dump(shstrtab, f, strtab, opts.dumpSectionData)
229    print "])"
230
231if __name__ == "__main__":
232    from optparse import OptionParser, OptionGroup
233    parser = OptionParser("usage: %prog [options] {files}")
234    parser.add_option("", "--dump-section-data", dest="dumpSectionData",
235                      help="Dump the contents of sections",
236                      action="store_true", default=False)
237    (opts, args) = parser.parse_args()
238
239    if not args:
240        args.append('-')
241
242    for arg in args:
243        dumpELF(arg, opts)
244