File Coverage

File:Dpkg/Shlibs/Objdump.pm
Coverage:17.7%

linestmtbrancondsubpodtimecode
1# Copyright © 2007-2010 Raphaël Hertzog <hertzog@debian.org>
2# Copyright © 2007-2009,2012-2015,2017-2018 Guillem Jover <guillem@debian.org>
3#
4# This program is free software; you can redistribute it and/or modify
5# it under the terms of the GNU General Public License as published by
6# the Free Software Foundation; either version 2 of the License, or
7# (at your option) any later version.
8#
9# This program is distributed in the hope that it will be useful,
10# but WITHOUT ANY WARRANTY; without even the implied warranty of
11# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12# GNU General Public License for more details.
13#
14# You should have received a copy of the GNU General Public License
15# along with this program.  If not, see <https://www.gnu.org/licenses/>.
16
17=encoding utf8
18
19 - 30
=head1 NAME

Dpkg::Shlibs::Objdump - symbol support via objdump

=head1 DESCRIPTION

This module provides a class that wraps objdump to handle symbols and
their attributes from a shared object.

B<Note>: This is a private module, its API can change at any time.

=cut
31
32package Dpkg::Shlibs::Objdump 0.01;
33
34
6
6
6
6
100
54
146
use strict;
35
6
6
6
6
12
2
244
use warnings;
36
6
6
6
6
16
6
272
use feature qw(state);
37
38
6
6
6
6
8
6
236
use Dpkg::Gettext;
39
6
6
6
6
20
4
204
use Dpkg::ErrorHandling;
40
6
6
6
6
5018
10
1772
use Dpkg::Shlibs::Objdump::Object;
41
42sub new {
43
0
0
0
    my $this = shift;
44
0
0
    my $class = ref($this) || $this;
45
0
    my $self = { objects => {} };
46
0
    bless $self, $class;
47
0
    return $self;
48}
49
50sub add_object {
51
0
0
0
    my ($self, $obj) = @_;
52
0
    my $id = $obj->get_id;
53
0
0
    if ($id) {
54
0
        $self->{objects}{$id} = $obj;
55    }
56
0
    return $id;
57}
58
59sub analyze {
60
0
0
0
    my ($self, $file) = @_;
61
0
    my $obj = Dpkg::Shlibs::Objdump::Object->new($file);
62
63
0
    return $self->add_object($obj);
64}
65
66sub locate_symbol {
67
0
0
0
    my ($self, $name) = @_;
68
0
0
    foreach my $obj (values %{$self->{objects}}) {
69
0
        my $sym = $obj->get_symbol($name);
70
0
0
0
        if (defined($sym) && $sym->{defined}) {
71
0
            return $sym;
72        }
73    }
74
0
    return;
75}
76
77sub get_object {
78
0
0
0
    my ($self, $objid) = @_;
79
0
0
    if ($self->has_object($objid)) {
80
0
        return $self->{objects}{$objid};
81    }
82
0
    return;
83}
84
85sub has_object {
86
0
0
0
    my ($self, $objid) = @_;
87
0
    return exists $self->{objects}{$objid};
88}
89
90use constant {
91    # ELF Class.
92
6
3738
    ELF_BITS_NONE           => 0,
93    ELF_BITS_32             => 1,
94    ELF_BITS_64             => 2,
95
96    # ELF Data encoding.
97    ELF_ORDER_NONE          => 0,
98    ELF_ORDER_2LSB          => 1,
99    ELF_ORDER_2MSB          => 2,
100
101    # ELF Machine.
102    EM_NONE                 => 0,
103    EM_SPARC                => 2,
104    EM_386                  => 3,
105    EM_68K                  => 4,
106    EM_MIPS                 => 8,
107    EM_SPARC64_OLD          => 11,
108    EM_PARISC               => 15,
109    EM_SPARC32PLUS          => 18,
110    EM_PPC                  => 20,
111    EM_PPC64                => 21,
112    EM_S390                 => 22,
113    EM_ARM                  => 40,
114    EM_ALPHA_OLD            => 41,
115    EM_SH                   => 42,
116    EM_SPARC64              => 43,
117    EM_IA64                 => 50,
118    EM_X86_64               => 62,
119    EM_OR1K                 => 92,
120    EM_AARCH64              => 183,
121    EM_ARCV2                => 195,
122    EM_RISCV                => 243,
123    EM_LOONGARCH            => 258,
124    EM_OR1K_OLD             => 0x8472,
125    EM_ALPHA                => 0x9026,
126    EM_S390_OLD             => 0xa390,
127    EM_NIOS32               => 0xfebb,
128
129    # ELF Version.
130    EV_NONE                 => 0,
131    EV_CURRENT              => 1,
132
133    # ELF Flags (might influence the ABI).
134    EF_ARM_ALIGN8           => 0x00000040,
135    EF_ARM_NEW_ABI          => 0x00000080,
136    EF_ARM_OLD_ABI          => 0x00000100,
137    EF_ARM_SOFT_FLOAT       => 0x00000200,
138    EF_ARM_HARD_FLOAT       => 0x00000400,
139    EF_ARM_EABI_MASK        => 0xff000000,
140
141    EF_IA64_ABI64           => 0x00000010,
142
143    EF_LOONGARCH_SOFT_FLOAT     => 0x00000001,
144    EF_LOONGARCH_SINGLE_FLOAT   => 0x00000002,
145    EF_LOONGARCH_DOUBLE_FLOAT   => 0x00000003,
146    EF_LOONGARCH_ABI_MASK       => 0x00000007,
147
148    EF_MIPS_ABI2            => 0x00000020,
149    EF_MIPS_32BIT           => 0x00000100,
150    EF_MIPS_FP64            => 0x00000200,
151    EF_MIPS_NAN2008         => 0x00000400,
152    EF_MIPS_ABI_MASK        => 0x0000f000,
153    EF_MIPS_ARCH_MASK       => 0xf0000000,
154
155    EF_OR1K_NODELAY         => 0x00000001,
156
157    EF_PPC64_ABI64          => 0x00000003,
158
159    EF_RISCV_FLOAT_ABI_SOFT     => 0x0000,
160    EF_RISCV_FLOAT_ABI_SINGLE   => 0x0002,
161    EF_RISCV_FLOAT_ABI_DOUBLE   => 0x0004,
162    EF_RISCV_FLOAT_ABI_QUAD     => 0x0006,
163    EF_RISCV_FLOAT_ABI_MASK     => 0x0006,
164    EF_RISCV_RVE                => 0x0008,
165
166    EF_SH_MACH_MASK         => 0x0000001f,
167
6
6
6
30
6
};
168
169# These map machine IDs to their name.
170my %elf_mach_name = (
171    EM_NONE()               => 'none',
172    EM_386()                => 'i386',
173    EM_68K()                => 'm68k',
174    EM_AARCH64()            => 'arm64',
175    EM_ALPHA()              => 'alpha',
176    EM_ARCV2()              => 'arcv2',
177    EM_ARM()                => 'arm',
178    EM_IA64()               => 'ia64',
179    EM_LOONGARCH()          => 'loong',
180    EM_MIPS()               => 'mips',
181    EM_NIOS32()             => 'nios2',
182    EM_OR1K()               => 'or1k',
183    EM_PARISC()             => 'hppa',
184    EM_PPC()                => 'ppc',
185    EM_PPC64()              => 'ppc64',
186    EM_RISCV()              => 'riscv',
187    EM_S390()               => 's390',
188    EM_SH()                 => 'sh',
189    EM_SPARC()              => 'sparc',
190    EM_SPARC64()            => 'sparc64',
191    EM_X86_64()             => 'amd64',
192);
193
194# These map alternative or old machine IDs to their canonical form.
195my %elf_mach_map = (
196    EM_ALPHA_OLD()          => EM_ALPHA,
197    EM_OR1K_OLD()           => EM_OR1K,
198    EM_S390_OLD()           => EM_S390,
199    EM_SPARC32PLUS()        => EM_SPARC,
200    EM_SPARC64_OLD()        => EM_SPARC64,
201);
202
203# These masks will try to expose processor flags that are ABI incompatible,
204# and as such are part of defining the architecture ABI. If uncertain it is
205# always better to not mask a flag, because that preserves the historical
206# behavior, and we do not drop dependencies.
207my %elf_flags_mask = (
208    # XXX: The mask for ARM had to be disabled due to objects in the wild
209    # with EABIv4, while EABIv5 is the current one, and the soft and hard
210    # flags not always being set on armel and armhf respectively, although
211    # the Tag_ABI_VFP_args in the ARM attribute section should always be
212    # present on armhf, and there are even cases where both soft and hard
213    # float flags are set at the same time(!). Once these are confirmed to
214    # be fixed, we could reconsider enabling the below for a more strict
215    # ABI mismatch check. See #853793.
216#   EM_ARM()                => EF_ARM_EABI_MASK |
217#                              EF_ARM_NEW_ABI | EF_ARM_OLD_ABI |
218#                              EF_ARM_SOFT_FLOAT | EF_ARM_HARD_FLOAT,
219    EM_IA64()               => EF_IA64_ABI64,
220    EM_LOONGARCH()          => EF_LOONGARCH_ABI_MASK,
221    EM_MIPS()               => EF_MIPS_ABI_MASK | EF_MIPS_ABI2,
222    EM_OR1K()               => EF_OR1K_NODELAY,
223    EM_PPC64()              => EF_PPC64_ABI64,
224    EM_RISCV()              => EF_RISCV_FLOAT_ABI_MASK | EF_RISCV_RVE,
225);
226
227sub get_format {
228
0
0
0
    my ($file) = @_;
229
0
    state %format;
230
231
0
0
    return $format{$file} if exists $format{$file};
232
233
0
    my $header;
234
235
0
0
    open my $fh, '<', $file or syserr(g_('cannot read %s'), $file);
236
0
    my $rc = read $fh, $header, 64;
237
0
0
0
    if (not defined $rc) {
238
0
        syserr(g_('cannot read %s'), $file);
239    } elsif ($rc != 64) {
240
0
        return;
241    }
242
0
    close $fh;
243
244
0
    my %elf;
245
246    # Unpack the identifier field.
247
0
    @elf{qw(magic bits endian vertype osabi verabi)} = unpack 'a4C5', $header;
248
249
0
0
    return unless $elf{magic} eq "\x7fELF";
250
0
0
    return unless $elf{vertype} == EV_CURRENT;
251
252
0
    my %abi;
253
0
    my ($elf_word, $elf_endian);
254
0
0
0
    if ($elf{bits} == ELF_BITS_32) {
255
0
        $abi{bits} = 32;
256
0
        $elf_word = 'L';
257    } elsif ($elf{bits} == ELF_BITS_64) {
258
0
        $abi{bits} = 64;
259
0
        $elf_word = 'Q';
260    } else {
261
0
        return;
262    }
263
0
0
0
    if ($elf{endian} == ELF_ORDER_2LSB) {
264
0
        $abi{endian} = 'l';
265
0
        $elf_endian = '<';
266    } elsif ($elf{endian} == ELF_ORDER_2MSB) {
267
0
        $abi{endian} = 'b';
268
0
        $elf_endian = '>';
269    } else {
270
0
        return;
271    }
272
273    # Unpack the endianness and size dependent fields.
274
0
    my $tmpl = "x16(S2Lx[${elf_word}3]L)${elf_endian}";
275
0
    @elf{qw(type mach version flags)} = unpack $tmpl, $header;
276
277    # Canonicalize the machine ID.
278
0
0
    $elf{mach} = $elf_mach_map{$elf{mach}} // $elf{mach};
279
0
0
    $abi{mach} = $elf_mach_name{$elf{mach}} // $elf{mach};
280
281    # Mask any processor flags that might not change the architecture ABI.
282
0
0
    $abi{flags} = $elf{flags} & ($elf_flags_mask{$elf{mach}} // 0);
283
284    # Normalize into a colon-separated string for easy comparison, and easy
285    # debugging aid.
286
0
    $format{$file} = join ':', 'ELF', @abi{qw(bits endian mach flags)};
287
288
0
    return $format{$file};
289}
290
291sub is_elf {
292
0
0
0
    my $file = shift;
293
0
0
    open(my $file_fh, '<', $file) or syserr(g_('cannot read %s'), $file);
294
0
    my ($header, $result) = ('', 0);
295
0
0
    if (read($file_fh, $header, 4) == 4) {
296
0
0
        $result = 1 if ($header =~ /^\177ELF$/);
297    }
298
0
    close($file_fh);
299
0
    return $result;
300}
301
302 - 308
=head1 CHANGES

=head2 Version 0.xx

This is a private module.

=cut
309
3101;