#!/usr/bin/env python # # Migration Stream Analyzer # # Copyright (c) 2015 Alexander Graf <agraf@suse.de> # # This library is free software; you can redistribute it and/or # modify it under the terms of the GNU Lesser General Public # License as published by the Free Software Foundation; either # version 2 of the License, or (at your option) any later version. # # This library 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 # Lesser General Public License for more details. # # You should have received a copy of the GNU Lesser General Public # License along with this library; if not, see <http://www.gnu.org/licenses/>. import numpy as np import json import os import argparse import collections import pprint def mkdir_p(path): try: os.makedirs(path) except OSError: pass class MigrationFile(object): def __init__(self, filename): self.filename = filename self.file = open(self.filename, "rb") def read64(self): return np.asscalar(np.fromfile(self.file, count=1, dtype='>i8')[0]) def read32(self): return np.asscalar(np.fromfile(self.file, count=1, dtype='>i4')[0]) def read16(self): return np.asscalar(np.fromfile(self.file, count=1, dtype='>i2')[0]) def read8(self): return np.asscalar(np.fromfile(self.file, count=1, dtype='>i1')[0]) def readstr(self, len = None): if len is None: len = self.read8() if len == 0: return "" return np.fromfile(self.file, count=1, dtype=('S%d' % len))[0] def readvar(self, size = None): if size is None: size = self.read8() if size == 0: return "" value = self.file.read(size) if len(value) != size: raise Exception("Unexpected end of %s at 0x%x" % (self.filename, self.file.tell())) return value def tell(self): return self.file.tell() # The VMSD description is at the end of the file, after EOF. Look for # the last NULL byte, then for the beginning brace of JSON. def read_migration_debug_json(self): QEMU_VM_VMDESCRIPTION = 0x06 # Remember the offset in the file when we started entrypos = self.file.tell() # Read the last 10MB self.file.seek(0, os.SEEK_END) endpos = self.file.tell() self.file.seek(max(-endpos, -10 * 1024 * 1024), os.SEEK_END) datapos = self.file.tell() data = self.file.read() # The full file read closed the file as well, reopen it self.file = open(self.filename, "rb") # Find the last NULL byte, then the first brace after that. This should # be the beginning of our JSON data. nulpos = data.rfind("\0") jsonpos = data.find("{", nulpos) # Check backwards from there and see whether we guessed right self.file.seek(datapos + jsonpos - 5, 0) if self.read8() != QEMU_VM_VMDESCRIPTION: raise Exception("No Debug Migration device found") jsonlen = self.read32() # Seek back to where we were at the beginning self.file.seek(entrypos, 0) return data[jsonpos:jsonpos + jsonlen] def close(self): self.file.close() class RamSection(object): RAM_SAVE_FLAG_COMPRESS = 0x02 RAM_SAVE_FLAG_MEM_SIZE = 0x04 RAM_SAVE_FLAG_PAGE = 0x08 RAM_SAVE_FLAG_EOS = 0x10 RAM_SAVE_FLAG_CONTINUE = 0x20 RAM_SAVE_FLAG_XBZRLE = 0x40 RAM_SAVE_FLAG_HOOK = 0x80 def __init__(self, file, version_id, ramargs, section_key): if version_id != 4: raise Exception("Unknown RAM version %d" % version_id) self.file = file self.section_key = section_key self.TARGET_PAGE_SIZE = ramargs['page_size'] self.dump_memory = ramargs['dump_memory'] self.write_memory = ramargs['write_memory'] self.sizeinfo = collections.OrderedDict() self.data = collections.OrderedDict() self.data['section sizes'] = self.sizeinfo self.name = '' if self.write_memory: self.files = { } if self.dump_memory: self.memory = collections.OrderedDict() self.data['memory'] = self.memory def __repr__(self): return self.data.__repr__() def __str__(self): return self.data.__str__() def getDict(self): return self.data def read(self): # Read all RAM sections while True: addr = self.file.read64() flags = addr & (self.TARGET_PAGE_SIZE - 1) addr &= ~(self.TARGET_PAGE_SIZE - 1) if flags & self.RAM_SAVE_FLAG_MEM_SIZE: while True: namelen = self.file.read8() # We assume that no RAM chunk is big enough to ever # hit the first byte of the address, so when we see # a zero here we know it has to be an address, not the # length of the next block. if namelen == 0: self.file.file.seek(-1, 1) break self.name = self.file.readstr(len = namelen) len = self.file.read64() self.sizeinfo[self.name] = '0x%016x' % len if self.write_memory: print self.name mkdir_p('./' + os.path.dirname(self.name)) f = open('./' + self.name, "wb") f.truncate(0) f.truncate(len) self.files[self.name] = f flags &= ~self.RAM_SAVE_FLAG_MEM_SIZE if flags & self.RAM_SAVE_FLAG_COMPRESS: if flags & self.RAM_SAVE_FLAG_CONTINUE: flags &= ~self.RAM_SAVE_FLAG_CONTINUE else: self.name = self.file.readstr() fill_char = self.file.read8() # The page in question is filled with fill_char now if self.write_memory and fill_char != 0: self.files[self.name].seek(addr, os.SEEK_SET) self.files[self.name].write(chr(fill_char) * self.TARGET_PAGE_SIZE) if self.dump_memory: self.memory['%s (0x%016x)' % (self.name, addr)] = 'Filled with 0x%02x' % fill_char flags &= ~self.RAM_SAVE_FLAG_COMPRESS elif flags & self.RAM_SAVE_FLAG_PAGE: if flags & self.RAM_SAVE_FLAG_CONTINUE: flags &= ~self.RAM_SAVE_FLAG_CONTINUE else: self.name = self.file.readstr() if self.write_memory or self.dump_memory: data = self.file.readvar(size = self.TARGET_PAGE_SIZE) else: # Just skip RAM data self.file.file.seek(self.TARGET_PAGE_SIZE, 1) if self.write_memory: self.files[self.name].seek(addr, os.SEEK_SET) self.files[self.name].write(data) if self.dump_memory: hexdata = " ".join("{0:02x}".format(ord(c)) for c in data) self.memory['%s (0x%016x)' % (self.name, addr)] = hexdata flags &= ~self.RAM_SAVE_FLAG_PAGE elif flags & self.RAM_SAVE_FLAG_XBZRLE: raise Exception("XBZRLE RAM compression is not supported yet") elif flags & self.RAM_SAVE_FLAG_HOOK: raise Exception("RAM hooks don't make sense with files") # End of RAM section if flags & self.RAM_SAVE_FLAG_EOS: break if flags != 0: raise Exception("Unknown RAM flags: %x" % flags) def __del__(self): if self.write_memory: for key in self.files: self.files[key].close() class HTABSection(object): HASH_PTE_SIZE_64 = 16 def __init__(self, file, version_id, device, section_key): if version_id != 1: raise Exception("Unknown HTAB version %d" % version_id) self.file = file self.section_key = section_key def read(self): header = self.file.read32() if (header > 0): # First section, just the hash shift return # Read until end marker while True: index = self.file.read32() n_valid = self.file.read16() n_invalid = self.file.read16() if index == 0 and n_valid == 0 and n_invalid == 0: break self.file.readvar(n_valid * self.HASH_PTE_SIZE_64) def getDict(self): return "" class VMSDFieldGeneric(object): def __init__(self, desc, file): self.file = file self.desc = desc self.data = "" def __repr__(self): return str(self.__str__()) def __str__(self): return " ".join("{0:02x}".format(ord(c)) for c in self.data) def getDict(self): return self.__str__() def read(self): size = int(self.desc['size']) self.data = self.file.readvar(size) return self.data class VMSDFieldInt(VMSDFieldGeneric): def __init__(self, desc, file): super(VMSDFieldInt, self).__init__(desc, file) self.size = int(desc['size']) self.format = '0x%%0%dx' % (self.size * 2) self.sdtype = '>i%d' % self.size self.udtype = '>u%d' % self.size def __repr__(self): if self.data < 0: return ('%s (%d)' % ((self.format % self.udata), self.data)) else: return self.format % self.data def __str__(self): return self.__repr__() def getDict(self): return self.__str__() def read(self): super(VMSDFieldInt, self).read() self.sdata = np.fromstring(self.data, count=1, dtype=(self.sdtype))[0] self.udata = np.fromstring(self.data, count=1, dtype=(self.udtype))[0] self.data = self.sdata return self.data class VMSDFieldUInt(VMSDFieldInt): def __init__(self, desc, file): super(VMSDFieldUInt, self).__init__(desc, file) def read(self): super(VMSDFieldUInt, self).read() self.data = self.udata return self.data class VMSDFieldIntLE(VMSDFieldInt): def __init__(self, desc, file): super(VMSDFieldIntLE, self).__init__(desc, file) self.dtype = '<i%d' % self.size class VMSDFieldBool(VMSDFieldGeneric): def __init__(self, desc, file): super(VMSDFieldBool, self).__init__(desc, file) def __repr__(self): return self.data.__repr__() def __str__(self): return self.data.__str__() def getDict(self): return self.data def read(self): super(VMSDFieldBool, self).read() if self.data[0] == 0: self.data = False else: self.data = True return self.data class VMSDFieldStruct(VMSDFieldGeneric): QEMU_VM_SUBSECTION = 0x05 def __init__(self, desc, file): super(VMSDFieldStruct, self).__init__(desc, file) self.data = collections.OrderedDict() # When we see compressed array elements, unfold them here new_fields = [] for field in self.desc['struct']['fields']: if not 'array_len' in field: new_fields.append(field) continue array_len = field.pop('array_len') field['index'] = 0 new_fields.append(field) for i in xrange(1, array_len): c = field.copy() c['index'] = i new_fields.append(c) self.desc['struct']['fields'] = new_fields def __repr__(self): return self.data.__repr__() def __str__(self): return self.data.__str__() def read(self): for field in self.desc['struct']['fields']: try: reader = vmsd_field_readers[field['type']] except: reader = VMSDFieldGeneric field['data'] = reader(field, self.file) field['data'].read() if 'index' in field: if field['name'] not in self.data: self.data[field['name']] = [] a = self.data[field['name']] if len(a) != int(field['index']): raise Exception("internal index of data field unmatched (%d/%d)" % (len(a), int(field['index']))) a.append(field['data']) else: self.data[field['name']] = field['data'] if 'subsections' in self.desc['struct']: for subsection in self.desc['struct']['subsections']: if self.file.read8() != self.QEMU_VM_SUBSECTION: raise Exception("Subsection %s not found at offset %x" % ( subsection['vmsd_name'], self.file.tell())) name = self.file.readstr() version_id = self.file.read32() self.data[name] = VMSDSection(self.file, version_id, subsection, (name, 0)) self.data[name].read() def getDictItem(self, value): # Strings would fall into the array category, treat # them specially if value.__class__ is ''.__class__: return value try: return self.getDictOrderedDict(value) except: try: return self.getDictArray(value) except: try: return value.getDict() except: return value def getDictArray(self, array): r = [] for value in array: r.append(self.getDictItem(value)) return r def getDictOrderedDict(self, dict): r = collections.OrderedDict() for (key, value) in dict.items(): r[key] = self.getDictItem(value) return r def getDict(self): return self.getDictOrderedDict(self.data) vmsd_field_readers = { "bool" : VMSDFieldBool, "int8" : VMSDFieldInt, "int16" : VMSDFieldInt, "int32" : VMSDFieldInt, "int32 equal" : VMSDFieldInt, "int32 le" : VMSDFieldIntLE, "int64" : VMSDFieldInt, "uint8" : VMSDFieldUInt, "uint16" : VMSDFieldUInt, "uint32" : VMSDFieldUInt, "uint32 equal" : VMSDFieldUInt, "uint64" : VMSDFieldUInt, "int64 equal" : VMSDFieldInt, "uint8 equal" : VMSDFieldInt, "uint16 equal" : VMSDFieldInt, "float64" : VMSDFieldGeneric, "timer" : VMSDFieldGeneric, "buffer" : VMSDFieldGeneric, "unused_buffer" : VMSDFieldGeneric, "bitmap" : VMSDFieldGeneric, "struct" : VMSDFieldStruct, "unknown" : VMSDFieldGeneric, } class VMSDSection(VMSDFieldStruct): def __init__(self, file, version_id, device, section_key): self.file = file self.data = "" self.vmsd_name = "" self.section_key = section_key desc = device if 'vmsd_name' in device: self.vmsd_name = device['vmsd_name'] # A section really is nothing but a FieldStruct :) super(VMSDSection, self).__init__({ 'struct' : desc }, file) ############################################################################### class MigrationDump(object): QEMU_VM_FILE_MAGIC = 0x5145564d QEMU_VM_FILE_VERSION = 0x00000003 QEMU_VM_EOF = 0x00 QEMU_VM_SECTION_START = 0x01 QEMU_VM_SECTION_PART = 0x02 QEMU_VM_SECTION_END = 0x03 QEMU_VM_SECTION_FULL = 0x04 QEMU_VM_SUBSECTION = 0x05 QEMU_VM_VMDESCRIPTION = 0x06 def __init__(self, filename): self.section_classes = { ( 'ram', 0 ) : [ RamSection, None ], ( 'spapr/htab', 0) : ( HTABSection, None ) } self.filename = filename self.vmsd_desc = None def read(self, desc_only = False, dump_memory = False, write_memory = False): # Read in the whole file file = MigrationFile(self.filename) # File magic data = file.read32() if data != self.QEMU_VM_FILE_MAGIC: raise Exception("Invalid file magic %x" % data) # Version (has to be v3) data = file.read32() if data != self.QEMU_VM_FILE_VERSION: raise Exception("Invalid version number %d" % data) self.load_vmsd_json(file) # Read sections self.sections = collections.OrderedDict() if desc_only: return ramargs = {} ramargs['page_size'] = self.vmsd_desc['page_size'] ramargs['dump_memory'] = dump_memory ramargs['write_memory'] = write_memory self.section_classes[('ram',0)][1] = ramargs while True: section_type = file.read8() if section_type == self.QEMU_VM_EOF: break elif section_type == self.QEMU_VM_SECTION_START or section_type == self.QEMU_VM_SECTION_FULL: section_id = file.read32() name = file.readstr() instance_id = file.read32() version_id = file.read32() section_key = (name, instance_id) classdesc = self.section_classes[section_key] section = classdesc[0](file, version_id, classdesc[1], section_key) self.sections[section_id] = section section.read() elif section_type == self.QEMU_VM_SECTION_PART or section_type == self.QEMU_VM_SECTION_END: section_id = file.read32() self.sections[section_id].read() else: raise Exception("Unknown section type: %d" % section_type) file.close() def load_vmsd_json(self, file): vmsd_json = file.read_migration_debug_json() self.vmsd_desc = json.loads(vmsd_json, object_pairs_hook=collections.OrderedDict) for device in self.vmsd_desc['devices']: key = (device['name'], device['instance_id']) value = ( VMSDSection, device ) self.section_classes[key] = value def getDict(self): r = collections.OrderedDict() for (key, value) in self.sections.items(): key = "%s (%d)" % ( value.section_key[0], key ) r[key] = value.getDict() return r ############################################################################### class JSONEncoder(json.JSONEncoder): def default(self, o): if isinstance(o, VMSDFieldGeneric): return str(o) return json.JSONEncoder.default(self, o) parser = argparse.ArgumentParser() parser.add_argument("-f", "--file", help='migration dump to read from', required=True) parser.add_argument("-m", "--memory", help='dump RAM contents as well', action='store_true') parser.add_argument("-d", "--dump", help='what to dump ("state" or "desc")', default='state') parser.add_argument("-x", "--extract", help='extract contents into individual files', action='store_true') args = parser.parse_args() jsonenc = JSONEncoder(indent=4, separators=(',', ': ')) if args.extract: dump = MigrationDump(args.file) dump.read(desc_only = True) print "desc.json" f = open("desc.json", "wb") f.truncate() f.write(jsonenc.encode(dump.vmsd_desc)) f.close() dump.read(write_memory = True) dict = dump.getDict() print "state.json" f = open("state.json", "wb") f.truncate() f.write(jsonenc.encode(dict)) f.close() elif args.dump == "state": dump = MigrationDump(args.file) dump.read(dump_memory = args.memory) dict = dump.getDict() print jsonenc.encode(dict) elif args.dump == "desc": dump = MigrationDump(args.file) dump.read(desc_only = True) print jsonenc.encode(dump.vmsd_desc) else: raise Exception("Please specify either -x, -d state or -d dump")