Detect MBR bootstrap on the images

Detect the bootloader that is installed on the MBR and assign it to
the BOOTSTRAP image property.

image_creator/bootloader.py

+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2015 GRNET S.A.
+#
+# 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 3 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, see <http://www.gnu.org/licenses/>.
+
+"""Module hosting code for determining the installed boot loader on an image.
+The bootloader signatures are taken from the "Boot Info Script" project:
+    https://github.com/arvidjaar/bootinfoscript
+"""
+
+# Master Boot Record Bootloaders
+MBR_LDR = [
+    # GRUB Legacy
+    "grub1",            # 0
+    # GRUB 2
+    "grub2",
+    # LILO (LInux LOader)
+    "lilo",
+    # SYSLINUX
+    "syslinux",
+    # Windows
+    "Windows",
+    # FreeBSD's boot0
+    "freebsd",          # 5
+    # NetBSD's Stage 0/SUSE generic MBR
+    "netbsd",
+    # OpenBSD's MBR
+    "openbsd",
+    # ReactOS
+    "reactos",
+    # FreeDOS
+    "freedos",
+    # MS-DOS
+    "msdos",            # 10
+    # Solaris
+    "solaris",
+    # ThinkPad MBR
+    "thinkpad",
+    # HP/Gateway
+    "hp",
+    # Plop Boot Manager
+    "plop",
+    # TrueCrypt boot loader
+    "truecrypt",        # 15
+    # Paragon Partition Manager
+    "paragon",
+    # Testdisk MBR
+    "testdist",
+    # GAG Graphical Boot Manager
+    "gag",
+    # BootIt Boot Manager
+    "bootit",
+    # DiskCryptor
+    "diskcryptor",  # 20
+    # xOSL (Extended Operating System Loader)
+    "xosl",
+    # Fbinst
+    "fbinst",
+    # Grub4Dos
+    "grub4dos",
+    # WEE boot manager
+    "wee",
+    # mbldr (Master Boot LoaDeR)
+    "mbldr",   # 25
+    # Libparted generic boot code
+    "libparted",
+    # ISOhybrid
+    "isohybrid",
+    # Acer PQservice MBR
+    "pqservice",
+]
+
+# 2-bytes MBR signature
+MBR_SIG2 = {
+    "\x3b\x48": 0,
+    "\xeb\x4c": 1,
+    "\xeb\x63": 1,
+    "\xeb\x04": 11,
+    "\x0e\xbe": 12,
+    "\x33\xed": 27,
+    "\x33\xff": 13,
+    "\xb8\x00": 14,
+    "\xea\x1e": 15,
+    "\xeb\x04":        11,
+    "\xeb\x31": 16,
+    "\xfa\x33": 10,
+    "\xfa\xeb": 2,
+    "\xfa\xfc": 8,
+    "\xfc\x31": 17,
+    "\xfc\x33": 18,
+    "\xfc\xeb": 19,
+}
+
+# 3-bytes MBR signature
+MBR_SIG3 = {
+    "\x33\xc0\x8e": 4,
+    "\x33\xc0\x90": 20,
+    "\x33\xc0\xfa": 3,
+    "\xea\x05\x00": 7,
+    "\xea\x05\x01": 21,
+    "\xeb\x5e\x00": 22,
+    "\xeb\x5e\x80": 23,
+    "\xeb\x5e\x90": 24,
+    "\xfa\x31\xc0": 3,
+    "\xfa\x31\xc9": 25,
+    "\xfa\x31\xed": 27,
+}
+
+# 4-bytes MBR signature
+MBR_SIG4 = {
+    "\xfa\xb8\x00\x00": 9,
+    "\xfa\xb8\x00\x10": 26,
+}
+
+# 8-bytes MBR signature
+MBR_SIG8 = {
+    "\x31\xc0\x8e\xd0\xbc\x00\x7c\x8e": 6,
+    "\x31\xc0\x8e\xd0\xbc\x00\x7c\xfb": 28,
+}
+
+
+def mbr_bootinfo(mbr):
+    """Inspect a Master Boot Record and return the installed bootloader"""
+    if mbr[:2] == '\x00\x00':
+        return "none"
+
+    try:
+        ret = MBR_SIG2[mbr[:2]]
+    except KeyError:
+        try:
+            ret = MBR_SIG3[mbr[:3]]
+        except KeyError:
+            try:
+                ret = MBR_SIG4[mbr[:4]]
+            except KeyError:
+                try:
+                    ret = MBR_SIG8[mbr[:8]]
+                except KeyError:
+                    return "unknown"
+
+    return MBR_LDR[ret]
+
+# vim: set sta sts=4 shiftwidth=4 sw=4 et ai :

image_creator/os_type/__init__.py

@@ -20,6 +20,7 @@ Systems for image creation.
 """
 
 from image_creator.util import FatalError
+from image_creator.bootloader import mbr_bootinfo
 
 import textwrap
 import re
@@ -321,6 +322,9 @@ class OSBase(object):
 
         self.out.info('Collecting image metadata ...', False)
 
+        mbr = self.image.g.pread_device('/dev/sda', 512, 0)
+        self.meta['BOOTSTRAP'] = mbr_bootinfo(mbr)
+
         with self.mount(readonly=True, silent=True):
             self._do_collect_metadata()