1 /*-
2 * Copyright (c) 2015 Kai Wang
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27 #include <sys/stat.h>
28 #include <assert.h>
29 #include <errno.h>
30 #include <stdlib.h>
31 #include <unistd.h>
32
33 #include "_libpe.h"
34
35 ELFTC_VCSID("$Id: libpe_init.c 3312 2016-01-10 09:23:51Z kaiwang27 $");
36
37 int
libpe_open_object(PE * pe)38 libpe_open_object(PE *pe)
39 {
40 struct stat sb;
41 mode_t mode;
42 char magic[sizeof(PE_DosHdr)];
43
44 if (fstat(pe->pe_fd, &sb) < 0)
45 return (-1);
46
47 mode = sb.st_mode;
48 pe->pe_fsize = (size_t) sb.st_size;
49
50 /* Reject unsupported file types. */
51 if (!S_ISREG(mode) && !S_ISCHR(mode) && !S_ISFIFO(mode) &&
52 !S_ISSOCK(mode)) {
53 errno = EINVAL;
54 return (-1);
55 }
56
57 /* Read/Write mode is not supported for non-regular file. */
58 if (pe->pe_cmd == PE_C_RDWR && !S_ISREG(mode)) {
59 errno = EINVAL;
60 return (-1);
61 }
62
63 /* The minimal file should at least contain a COFF header. */
64 if (S_ISREG(mode) && pe->pe_fsize < sizeof(PE_CoffHdr)) {
65 errno = ENOENT;
66 return (-1);
67 }
68
69 /*
70 * Search for MS-DOS header or COFF header.
71 */
72
73 if (read(pe->pe_fd, magic, 2) != 2) {
74 errno = EIO;
75 return (-1);
76 }
77
78 if (magic[0] == 'M' && magic[1] == 'Z') {
79 pe->pe_obj = PE_O_PE32;
80 if (read(pe->pe_fd, &magic[2], sizeof(PE_DosHdr) - 2) !=
81 (ssize_t) sizeof(PE_DosHdr) - 2) {
82 errno = EIO;
83 return (-1);
84 }
85 return (libpe_parse_msdos_header(pe, magic));
86
87 } else if (magic[0] == 'P' && magic[1] == 'E') {
88 if (read(pe->pe_fd, magic, 2) != 2) {
89 errno = EIO;
90 return (-1);
91 }
92 if (magic[0] == '\0' && magic[1] == '\0') {
93 pe->pe_obj = PE_O_PE32;
94 if (read(pe->pe_fd, magic, sizeof(PE_CoffHdr)) !=
95 (ssize_t) sizeof(PE_CoffHdr)) {
96 errno = EIO;
97 return (-1);
98 }
99 return (libpe_parse_coff_header(pe, magic));
100 }
101 errno = ENOENT;
102 return (-1);
103
104 } else {
105 pe->pe_obj = PE_O_COFF;
106 if (read(pe->pe_fd, &magic[2], sizeof(PE_CoffHdr) - 2) !=
107 (ssize_t) sizeof(PE_CoffHdr) - 2) {
108 errno = EIO;
109 return (-1);
110 }
111 return (libpe_parse_coff_header(pe, magic));
112 }
113 }
114
115 void
libpe_release_object(PE * pe)116 libpe_release_object(PE *pe)
117 {
118 PE_Scn *ps, *_ps;
119
120 if (pe->pe_dh)
121 free(pe->pe_dh);
122
123 if (pe->pe_rh) {
124 free(pe->pe_rh->rh_compid);
125 free(pe->pe_rh->rh_cnt);
126 free(pe->pe_rh);
127 }
128
129 if (pe->pe_ch)
130 free(pe->pe_ch);
131
132 if (pe->pe_oh)
133 free(pe->pe_oh);
134
135 if (pe->pe_dd)
136 free(pe->pe_dd);
137
138 if (pe->pe_stub)
139 free(pe->pe_stub);
140
141 STAILQ_FOREACH_SAFE(ps, &pe->pe_scn, ps_next, _ps)
142 libpe_release_scn(ps);
143
144 free(pe);
145 }
146