1*f8fb3368SJohn Marino /*-
2*f8fb3368SJohn Marino * Copyright (c) 2006,2008-2011 Joseph Koshy
3*f8fb3368SJohn Marino * All rights reserved.
4*f8fb3368SJohn Marino *
5*f8fb3368SJohn Marino * Redistribution and use in source and binary forms, with or without
6*f8fb3368SJohn Marino * modification, are permitted provided that the following conditions
7*f8fb3368SJohn Marino * are met:
8*f8fb3368SJohn Marino * 1. Redistributions of source code must retain the above copyright
9*f8fb3368SJohn Marino * notice, this list of conditions and the following disclaimer.
10*f8fb3368SJohn Marino * 2. Redistributions in binary form must reproduce the above copyright
11*f8fb3368SJohn Marino * notice, this list of conditions and the following disclaimer in the
12*f8fb3368SJohn Marino * documentation and/or other materials provided with the distribution.
13*f8fb3368SJohn Marino *
14*f8fb3368SJohn Marino * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15*f8fb3368SJohn Marino * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16*f8fb3368SJohn Marino * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17*f8fb3368SJohn Marino * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18*f8fb3368SJohn Marino * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19*f8fb3368SJohn Marino * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20*f8fb3368SJohn Marino * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21*f8fb3368SJohn Marino * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22*f8fb3368SJohn Marino * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23*f8fb3368SJohn Marino * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24*f8fb3368SJohn Marino * SUCH DAMAGE.
25*f8fb3368SJohn Marino */
26*f8fb3368SJohn Marino
27*f8fb3368SJohn Marino #include <libelf.h>
28*f8fb3368SJohn Marino
29*f8fb3368SJohn Marino #include "_libelf.h"
30*f8fb3368SJohn Marino
31*f8fb3368SJohn Marino ELFTC_VCSID("$Id: elf_begin.c 2364 2011-12-28 17:55:25Z jkoshy $");
32*f8fb3368SJohn Marino
33*f8fb3368SJohn Marino Elf *
elf_begin(int fd,Elf_Cmd c,Elf * a)34*f8fb3368SJohn Marino elf_begin(int fd, Elf_Cmd c, Elf *a)
35*f8fb3368SJohn Marino {
36*f8fb3368SJohn Marino Elf *e;
37*f8fb3368SJohn Marino
38*f8fb3368SJohn Marino e = NULL;
39*f8fb3368SJohn Marino
40*f8fb3368SJohn Marino if (LIBELF_PRIVATE(version) == EV_NONE) {
41*f8fb3368SJohn Marino LIBELF_SET_ERROR(SEQUENCE, 0);
42*f8fb3368SJohn Marino return (NULL);
43*f8fb3368SJohn Marino }
44*f8fb3368SJohn Marino
45*f8fb3368SJohn Marino switch (c) {
46*f8fb3368SJohn Marino case ELF_C_NULL:
47*f8fb3368SJohn Marino return (NULL);
48*f8fb3368SJohn Marino
49*f8fb3368SJohn Marino case ELF_C_WRITE:
50*f8fb3368SJohn Marino /*
51*f8fb3368SJohn Marino * The ELF_C_WRITE command is required to ignore the
52*f8fb3368SJohn Marino * descriptor passed in.
53*f8fb3368SJohn Marino */
54*f8fb3368SJohn Marino a = NULL;
55*f8fb3368SJohn Marino break;
56*f8fb3368SJohn Marino
57*f8fb3368SJohn Marino case ELF_C_RDWR:
58*f8fb3368SJohn Marino if (a != NULL) { /* not allowed for ar(1) archives. */
59*f8fb3368SJohn Marino LIBELF_SET_ERROR(ARGUMENT, 0);
60*f8fb3368SJohn Marino return (NULL);
61*f8fb3368SJohn Marino }
62*f8fb3368SJohn Marino /*FALLTHROUGH*/
63*f8fb3368SJohn Marino case ELF_C_READ:
64*f8fb3368SJohn Marino /*
65*f8fb3368SJohn Marino * Descriptor `a' could be for a regular ELF file, or
66*f8fb3368SJohn Marino * for an ar(1) archive. If descriptor `a' was opened
67*f8fb3368SJohn Marino * using a valid file descriptor, we need to check if
68*f8fb3368SJohn Marino * the passed in `fd' value matches the original one.
69*f8fb3368SJohn Marino */
70*f8fb3368SJohn Marino if (a &&
71*f8fb3368SJohn Marino ((a->e_fd != -1 && a->e_fd != fd) || c != a->e_cmd)) {
72*f8fb3368SJohn Marino LIBELF_SET_ERROR(ARGUMENT, 0);
73*f8fb3368SJohn Marino return (NULL);
74*f8fb3368SJohn Marino }
75*f8fb3368SJohn Marino break;
76*f8fb3368SJohn Marino
77*f8fb3368SJohn Marino default:
78*f8fb3368SJohn Marino LIBELF_SET_ERROR(ARGUMENT, 0);
79*f8fb3368SJohn Marino return (NULL);
80*f8fb3368SJohn Marino
81*f8fb3368SJohn Marino }
82*f8fb3368SJohn Marino
83*f8fb3368SJohn Marino if (a == NULL)
84*f8fb3368SJohn Marino e = _libelf_open_object(fd, c, 1);
85*f8fb3368SJohn Marino else if (a->e_kind == ELF_K_AR)
86*f8fb3368SJohn Marino e = _libelf_ar_open_member(a->e_fd, c, a);
87*f8fb3368SJohn Marino else
88*f8fb3368SJohn Marino (e = a)->e_activations++;
89*f8fb3368SJohn Marino
90*f8fb3368SJohn Marino return (e);
91*f8fb3368SJohn Marino }
92