Utility to create a.out [kernels] from an ELF one.

This is needed on sparc64 (and maybe all OpenFirmware based machines) as
most [all?] OpenBoot PROM's require either an a.out or FCode boot image.

Submitted by:	jake

1 files changed, 156 insertions, 0 deletions

diff --git a/usr.bin/elf2aout/elf2aout.c b/usr.bin/elf2aout/elf2aout.c
new file mode 100644
index 0000000..71df171
--- /dev/null
+++ b/usr.bin/elf2aout/elf2aout.c
@@ -0,0 +1,156 @@
+/*-
+ * Copyright (c) 2002 Jake Burkholder
+ * 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.
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <sys/elf64.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+
+#include <err.h>
+#include <fcntl.h>
+
+#define	be16toh(x)	(x)
+#define	be32toh(x)	(x)
+#define	be64toh(x)	(x)
+#define	htobe32(x)	(x)
+
+struct exec {
+	u_int	a_magic;
+	u_int	a_text;
+	u_int	a_data;
+	u_int	a_bss;
+	u_int	a_syms;
+	u_int	a_entry;
+	u_int	a_trsize;
+	u_int	a_drsize;
+};
+#define A_MAGIC 0x01030107
+
+extern char *optarg;
+extern int optind;
+
+static void usage(void);
+
+/*
+ * elf to a.out converter for freebsd/sparc64 bootblocks.
+ */
+int
+main(int ac, char **av)
+{
+	Elf64_Quarter phentsize;
+	Elf64_Quarter machine;
+	Elf64_Quarter phnum;
+	Elf64_Size filesz;
+	Elf64_Size memsz;
+	Elf64_Addr entry;
+	Elf64_Off offset;
+	Elf64_Off phoff;
+	Elf64_Half type;
+	struct stat sb;
+	struct exec a;
+	Elf64_Phdr *p;
+	Elf64_Ehdr *e;
+	void *v;
+	int efd;
+	int fd;
+	int c;
+	int i;
+
+	while ((c = getopt(ac, av, "o:")) != -1)
+		switch (c) {
+		case 'o':
+			if ((fd = open(optarg, O_CREAT|O_RDWR, 0644)) < 0)
+				err(1, "%s", optarg);
+			break;
+		case '?':
+		default:
+			usage();
+		}
+	ac -= optind;
+	av += optind;
+	if (ac == 0)
+		usage();
+
+	if ((efd = open(*av, O_RDONLY)) < 0 || fstat(efd, &sb) < 0)
+		err(1, NULL);
+	v = mmap(NULL, sb.st_size, PROT_READ, MAP_SHARED, efd, 0);
+	if ((e = v) == MAP_FAILED)
+		err(1, NULL);
+
+	if (!IS_ELF(*e))
+		errx(1, "not an elf file");
+	if (e->e_ident[EI_CLASS] != ELFCLASS64)
+		errx(1, "wrong class");
+	if (e->e_ident[EI_DATA] != ELFDATA2MSB)
+		errx(1, "wrong data format");
+	if (e->e_ident[EI_VERSION] != EV_CURRENT)
+		errx(1, "wrong elf version");
+	machine = be16toh(e->e_machine);
+	if (machine != EM_SPARCV9)
+		errx(1, "wrong machine type");
+	phentsize = be16toh(e->e_phentsize);
+	if (phentsize != sizeof(*p))
+		errx(1, "phdr size mismatch");
+
+	entry = be64toh(e->e_entry);
+	phoff = be64toh(e->e_phoff);
+	phnum = be16toh(e->e_phnum);
+	p = (Elf64_Phdr *)((char *)e + phoff);
+	bzero(&a, sizeof(a));
+	for (i = 0; i < phnum; i++) {
+		type = be32toh(p[i].p_type);
+		switch (type) {
+		case PT_LOAD:
+			if (a.a_magic != 0)
+				errx(1, "too many loadable segments");
+			filesz = be64toh(p[i].p_filesz);
+			memsz = be64toh(p[i].p_memsz);
+			offset = be64toh(p[i].p_offset);
+			a.a_magic = htobe32(A_MAGIC);
+			a.a_text = htobe32(filesz);
+			a.a_bss = htobe32(memsz - filesz);
+			a.a_entry = htobe32(entry);
+			if (write(fd, &a, sizeof(a)) != sizeof(a) ||
+			    write(fd, (char *)e + offset, filesz) != filesz)
+				err(1, NULL);
+			break;
+		default:
+			break;
+		}
+	}
+
+	return (0);
+}
+
+static void
+usage(void)
+{
+
+	errx(1, "usage: elftoaout -o outfile infile");
+}