[ipaccess] Start adding a tool that analyzes the ipaccess header

So far I have not much idea about the format. It is starting with
the magic byte and the header is spanning until the next occurence
of the " SDP" marker.
diff --git a/openbsc/src/Makefile.am b/openbsc/src/Makefile.am
index de413d5..3f98bda 100644
--- a/openbsc/src/Makefile.am
+++ b/openbsc/src/Makefile.am
@@ -2,7 +2,7 @@
 AM_CFLAGS=-Wall
 
 sbin_PROGRAMS = bsc_hack bs11_config ipaccess-find ipaccess-config \
-                isdnsync bsc_mgcp
+                isdnsync bsc_mgcp ipaccess_firmware
 noinst_LIBRARIES = libbsc.a libmsc.a libvty.a libsccp.a
 noinst_HEADERS = vty/cardshell.h
 
@@ -38,3 +38,5 @@
 
 bsc_mgcp_SOURCES = bsc_mgcp.c msgb.c talloc.c debug.c select.c timer.c telnet_interface.c
 bsc_mgcp_LDADD = libvty.a
+
+ipaccess_firmware_SOURCES = ipaccess-firmware/ipaccess-firmware.c
diff --git a/openbsc/src/ipaccess-firmware/ipaccess-firmware.c b/openbsc/src/ipaccess-firmware/ipaccess-firmware.c
new file mode 100644
index 0000000..0f93629
--- /dev/null
+++ b/openbsc/src/ipaccess-firmware/ipaccess-firmware.c
@@ -0,0 +1,67 @@
+/* Routines for parsing an ipacces SDP firmware file */
+
+/* (C) 2009 by Holger Hans Peter Freyther <zecke@selfish.org>
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+
+
+static void analyze_file(int fd)
+{
+	char buf[4096];
+	int rc;
+
+	rc = read(fd, buf, 4);
+	if (rc <= 0) {
+		fprintf(stderr, "Not enough space for the header.\n");
+		return;
+	}
+
+	if (strcmp(buf, " SDP") != 0) {
+		fprintf(stderr, "Wrong magic number at the beginning of the file.\n");
+		return;
+	}
+
+	printf("Printing header information:\n");
+}
+
+int main(int argc, char** argv)
+{
+	int i, fd;
+
+	for (i = 1; i < argc; ++i) {
+		printf("Opening possible firmware '%s'\n", argv[i]);
+		fd = open(argv[i], O_RDONLY);
+		if (!fd) {
+			perror("nada");
+			continue;
+		}
+
+		analyze_file(fd);
+	}
+
+	return EXIT_SUCCESS;
+}