flesh out more of mach-o support (disabled for now)

1 files changed, 128 insertions, 0 deletions

diff --git a/paxmacho.c b/paxmacho.c
new file mode 100644
index 0000000..59099a0
--- /dev/null
+++ b/paxmacho.c
@@ -0,0 +1,128 @@
+/*
+ * Copyright 2003-2005 Gentoo Foundation
+ * Distributed under the terms of the GNU General Public License v2
+ * $Header: /var/cvsroot/gentoo-projects/pax-utils/paxmacho.c,v 1.1 2005/11/02 04:23:21 vapier Exp $
+ *
+ * Copyright 2005 Ned Ludd        - <solar@gentoo.org>
+ * Copyright 2005 Mike Frysinger  - <vapier@gentoo.org>
+ */
+
+#include <stdio.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include "paxinc.h"
+
+#define argv0 "paxmacho"
+
+/*
+ * Setup a bunch of helper functions to translate
+ * binary defines into readable strings.
+ */
+#define QUERY(n) { #n, n }
+typedef struct {
+	const char *str;
+	int value;
+} pairtype;
+static inline const char *find_pairtype(pairtype *pt, int type)
+{
+	int i;
+	for (i = 0; pt[i].str; ++i)
+		if (type == pt[i].value)
+			return pt[i].str;
+	return "UNKNOWN TYPE";
+}
+
+/* translate misc mach-o MH_ defines */
+static pairtype macho_mh_type[] = {
+	QUERY(MH_OBJECT),
+	QUERY(MH_EXECUTE),
+	QUERY(MH_BUNDLE),
+	QUERY(MH_DYLIB),
+	QUERY(MH_PRELOAD),
+	QUERY(MH_CORE),
+	QUERY(MH_DYLINKER),
+	{ 0, 0 }
+};
+const char *get_machomhtype(int mh_type)
+{
+	return find_pairtype(macho_mh_type, mh_type);
+}
+
+
+/* Read a macho into memory */
+#define IS_MACHO_MAGIC(m) \
+	(m == MH_MAGIC    || m == MH_CIGAM || \
+	 m == MH_MAGIC_64 || m == MH_CIGAM_64)
+#define DO_WE_LIKE_MACHO(buff) 1
+machoobj *readmacho(const char *filename)
+{
+	struct stat st;
+	int fd;
+	machoobj *macho;
+	struct mach_header *mhdr;
+
+	if (stat(filename, &st) == -1)
+		return NULL;
+
+	if ((fd = open(filename, O_RDONLY)) == -1)
+		return NULL;
+
+	/* make sure we have enough bytes to scan e_ident */
+	if (st.st_size <= sizeof(struct mach_header))
+		goto close_fd_and_return;
+
+	macho = (machoobj*)malloc(sizeof(*macho));
+	if (macho == NULL)
+		goto close_fd_and_return;
+	memset(macho, 0x00, sizeof(*macho));
+
+	macho->fd = fd;
+	macho->len = st.st_size;
+	macho->data = (char*)mmap(0, macho->len, PROT_READ, MAP_PRIVATE, fd, 0);
+	if (macho->data == (char*)MAP_FAILED) {
+		warn("mmap on '%s' of %li bytes failed :(", filename, (unsigned long)macho->len);
+		goto free_macho_and_return;
+	}
+
+	mhdr = (struct mach_header*)macho->data;
+	do_reverse_endian = (mhdr->magic == MH_CIGAM || mhdr->magic == MH_CIGAM_64);
+	macho->macho_class = (EGET(mhdr->magic) == MH_MAGIC ? MH_MAGIC : MH_MAGIC_64);
+
+	if (!IS_MACHO_MAGIC(mhdr->magic)) /* make sure we have an macho */
+		goto unmap_data_and_return;
+	if (1 || !DO_WE_LIKE_MACHO(mhdr)) { /* check class and stuff */
+		warn("we no likey %s: {%i:%s}",
+		     filename,
+		     (int)EGET(mhdr->filetype), get_machomhtype(EGET(mhdr->filetype)));
+		goto unmap_data_and_return;
+	}
+
+	macho->filename = filename;
+	macho->base_filename = strrchr(filename, '/');
+	if (macho->base_filename == NULL)
+		macho->base_filename = macho->filename;
+	else
+		macho->base_filename = macho->base_filename + 1;
+	macho->mhdr = (void*)macho->data;
+
+	return macho;
+
+unmap_data_and_return:
+	munmap(macho->data, macho->len);
+free_macho_and_return:
+	free(macho);
+close_fd_and_return:
+	close(fd);
+	return NULL;
+}
+
+/* undo the readmacho() stuff */
+void unreadmacho(machoobj *macho)
+{
+	munmap(macho->data, macho->len);
+	close(macho->fd);
+	free(macho);
+}