Utility to "brand" ELF binaries.

Man page to come...
For now use: <brandelf -t Linux linuxbin> to brand, and just
<brandelf> to verify branding on a ELF file. FreeBSD native is
set with <brandelf -t FreeBSD freebsdbin>.

usr.bin/brandelf/Makefile

@@ -0,0 +1,5 @@
+PROG=	brandelf
+
+NOMAN=	brandelf.1
+
+.include <bsd.prog.mk>

usr.bin/brandelf/brandelf.c

@@ -0,0 +1,113 @@
+/*-
+ * Copyright (c) 1996 Søren Schmidt
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer
+ *    in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software withough specific prior written permission
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *  $Id$
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <sys/imgact_elf.h>
+
+int usage();
+
+main(int argc, char **argv)
+{
+	extern char *optarg;
+	extern int optind;
+
+	char type[10] = "FreeBSD";
+	int ch, change = 0, verbose = 0;
+
+	while ((ch = getopt(argc, argv, "t:v")) != EOF)
+		switch (ch) {
+		case 'v':
+			verbose = 1;
+			break;
+		case 't':
+			change = 1;
+			strcpy(type, optarg);
+			break;
+		default:
+			usage();
+	}
+	argc -= optind;
+	argv += optind;
+	if (!argc) {
+		fprintf(stderr, "No file(s) specified.\n");
+		exit(1);
+	}
+	while (argc) {
+		int fd;
+		char buffer[EI_NINDENT];
+		char string[(EI_NINDENT-EI_SPARE)+1];
+
+		if ((fd = open(argv[0], O_RDWR, 0)) < 0) {
+			fprintf(stderr, "No such file %s.\n", argv[0]);
+			goto fail;
+			
+		}
+		if (read(fd, buffer, EI_NINDENT) < EI_NINDENT) {
+			fprintf(stderr, "File '%s' too short.\n", argv[0]);
+			goto fail;
+		}
+		if (buffer[0] != ELFMAG0 || buffer[1] != ELFMAG1 ||
+		    buffer[2] != ELFMAG2 || buffer[3] != ELFMAG3) {
+			fprintf(stderr, "File '%s' is not ELF format.\n",
+				argv[0]);
+			goto fail;
+		}		
+		if (!change) {
+			bzero(string, sizeof(string));
+			strncpy(string, &buffer[EI_SPARE], EI_NINDENT-EI_SPARE);
+			if (strlen(string)) {
+				fprintf(stdout, "File '%s' is of brand '%s'.\n",
+					argv[0], string);
+			}
+			else
+				fprintf(stdout, "File '%s' has no branding.\n",
+					argv[0]);
+		}
+		else {
+			strncpy(&buffer[EI_SPARE], type, EI_NINDENT-EI_SPARE);
+			lseek(fd, 0, SEEK_SET);
+			if (write(fd, buffer, EI_NINDENT) != EI_NINDENT) {
+				fprintf(stderr, "Error writing %s\n", argv[0]);
+				goto fail;
+			}
+		}
+fail:
+		argc--;
+		argv++;
+	}
+}
+
+int
+usage()
+{
+	fprintf(stderr, "Usage: brandelf [-t string] file ...\n");
+}