xref: /freebsd/usr.bin/brandelf/brandelf.c (revision b97fa2ef508bb1cc99621edb8b6d03845b55b8bd)
1 /*-
2  * Copyright (c) 1996 S�ren Schmidt
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  *    in this position and unchanged.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software withough specific prior written permission
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  *
28  *  $FreeBSD$
29  */
30 
31 #include <stdlib.h>
32 #include <stdio.h>
33 #include <string.h>
34 #include <unistd.h>
35 #include <fcntl.h>
36 #include <sys/imgact_elf.h>
37 
38 int usage(void);
39 
40 int
41 main(int argc, char **argv)
42 {
43 
44 	const char *type = "FreeBSD";
45 	int retval = 0;
46 	int ch, change = 0, verbose = 0;
47 
48 	while ((ch = getopt(argc, argv, "t:v")) != EOF)
49 		switch (ch) {
50 		case 'v':
51 			verbose = 1;
52 			break;
53 		case 't':
54 			change = 1;
55 			type = optarg;
56 			break;
57 		default:
58 			usage();
59 	}
60 	argc -= optind;
61 	argv += optind;
62 	if (!argc) {
63 		fprintf(stderr, "No file(s) specified.\n");
64 		exit(1);
65 	}
66 	while (argc) {
67 		int fd;
68 		char buffer[EI_NINDENT];
69 		char string[(EI_NINDENT-EI_SPARE)+1];
70 
71 		if ((fd = open(argv[0], O_RDWR, 0)) < 0) {
72 			fprintf(stderr, "No such file %s.\n", argv[0]);
73 			retval = 1;
74 			goto fail;
75 
76 		}
77 		if (read(fd, buffer, EI_NINDENT) < EI_NINDENT) {
78 			fprintf(stderr, "File '%s' too short.\n", argv[0]);
79 			retval = 1;
80 			goto fail;
81 		}
82 		if (buffer[0] != ELFMAG0 || buffer[1] != ELFMAG1 ||
83 		    buffer[2] != ELFMAG2 || buffer[3] != ELFMAG3) {
84 			fprintf(stderr, "File '%s' is not ELF format.\n",
85 				argv[0]);
86 			retval = 1;
87 			goto fail;
88 		}
89 		if (!change) {
90 			bzero(string, sizeof(string));
91 			strncpy(string, &buffer[EI_SPARE], EI_NINDENT-EI_SPARE);
92 			if (strlen(string)) {
93 				fprintf(stdout, "File '%s' is of brand '%s'.\n",
94 					argv[0], string);
95 			}
96 			else
97 				fprintf(stdout, "File '%s' has no branding.\n",
98 					argv[0]);
99 		}
100 		else {
101 			strncpy(&buffer[EI_SPARE], type, EI_NINDENT-EI_SPARE);
102 			lseek(fd, 0, SEEK_SET);
103 			if (write(fd, buffer, EI_NINDENT) != EI_NINDENT) {
104 				fprintf(stderr, "Error writing %s\n", argv[0]);
105 			retval = 1;
106 				goto fail;
107 			}
108 		}
109 fail:
110 		argc--;
111 		argv++;
112 	}
113 
114 	return retval;
115 }
116 
117 int
118 usage(void)
119 {
120 	fprintf(stderr, "Usage: brandelf [-t string] file ...\n");
121 	exit(1);
122 }
123