from xnu import *
from utils import *
from process import *
from pmap import *
def _GetIntegerDataFromTask(u_ptr, task_abi):
"""
params:
u_ptr : int - pointer in user memory
task_abi : int - what kind of user program is running
returns:
int - value stored at specified u_ptr.
"""
if kern.arch != "x86_64":
raise ValueError("This function does not work for non x86_64 arch")
if task_abi == 0xf :
return unsigned(dereference(kern.GetValueFromAddress(u_ptr, 'uint64_t *')))
else:
return unsigned(dereference(kern.GetValueFromAddress(u_ptr, 'uint32_t *')))
def GetBinaryNameForPC(pc_val, user_lib_info = None):
""" find the binary in user_lib_info that the passed pc_val falls in range of.
params:
pc_val : int - integer form of the pc address
user_lib_info: [] of [] which hold start, end, binary name
returns:
str - Name of binary or "unknown" if not found.
"""
retval = "unknown"
if not user_lib_info:
return retval
matches = []
for info in user_lib_info:
if pc_val >= info[0] and pc_val <= info[1]:
matches.append((pc_val - info[0], info[2]))
matches.sort()
if matches:
retval = matches[0][1]
return retval
def ShowX86UserStack(thread, user_lib_info = None):
""" Display user space stack frame and pc addresses.
params:
thread: obj referencing thread value
returns:
Nothing
"""
iss = Cast(thread.machine.iss, 'x86_saved_state_t *')
abi = int(iss.flavor)
user_ip = 0
user_frame = 0
user_abi_ret_offset = 0
if abi == 0xf:
debuglog("User process is 64 bit")
user_ip = iss.uss.ss_64.isf.rip
user_frame = iss.uss.ss_64.rbp
user_abi_ret_offset = 8
else:
debuglog("user process is 32 bit")
user_ip = iss.uss.ss_32.eip
user_frame = iss.uss.ss_32.ebp
user_abi_ret_offset = 4
if user_ip == 0:
print "This activation does not appear to have a valid user context."
return False
cur_ip = user_ip
cur_frame = user_frame
debuglog("ip= 0x%x , fr = 0x%x " % (cur_ip, cur_frame))
kdp_pmap_addr = unsigned(addressof(kern.globals.kdp_pmap))
if not WriteInt64ToMemoryAddress(unsigned(thread.task.map.pmap), kdp_pmap_addr):
print "Failed to write in kdp_pmap = 0x{0:0>16x} value.".format(thread.task.map.pmap)
return False
debuglog("newpmap = 0x{:x}".format(kern.globals.kdp_pmap))
frameformat = "{0:d} FP: 0x{1:x} PC: 0x{2:x}"
if user_lib_info is not None:
frameformat = "{0:d} {3: <30s} 0x{2:x}"
print frameformat.format(0, cur_frame, cur_ip, GetBinaryNameForPC(cur_ip, user_lib_info))
print kern.Symbolicate(cur_ip)
tmp_frame = unsigned(cur_frame)
prev_frame = _GetIntegerDataFromTask(tmp_frame, abi)
prev_ip = _GetIntegerDataFromTask(tmp_frame + user_abi_ret_offset, abi)
frameno = 1
while prev_frame and prev_frame != 0x0000000800000008:
print frameformat.format(frameno, prev_frame, prev_ip, GetBinaryNameForPC(prev_ip, user_lib_info))
print kern.Symbolicate(prev_ip)
prev_ip = _GetIntegerDataFromTask(prev_frame + user_abi_ret_offset, abi)
prev_frame = _GetIntegerDataFromTask(prev_frame, abi)
frameno +=1
if not WriteInt64ToMemoryAddress(0, kdp_pmap_addr):
print "Failed to write in kdp_pmap = 0"
return False
return
def _PrintARMUserStack(task, cur_pc, cur_fp, framesize, frametype, frameformat, user_lib_info=None):
if cur_pc == 0:
"No valid user context for this activation."
return
frameno = 0
print frameformat.format(frameno, cur_fp, cur_pc, GetBinaryNameForPC(cur_pc, user_lib_info))
while True:
frameno = frameno + 1
frame = GetUserDataAsString(task, cur_fp, framesize)
cur_fp = _ExtractDataFromString(frame, 0, frametype)
cur_pc = _ExtractDataFromString(frame, (framesize / 2), frametype)
if not cur_fp:
break
print frameformat.format(frameno, cur_fp, cur_pc, GetBinaryNameForPC(cur_pc, user_lib_info))
def ShowARMUserStack(thread, user_lib_info = None):
cur_pc = unsigned(thread.machine.PcbData.pc)
cur_fp = unsigned(thread.machine.PcbData.r[7])
frameformat = "{0:>2d} FP: 0x{1:x} PC: 0x{2:x}"
if user_lib_info is not None:
frameformat = "{0:>2d} {3: <30s} 0x{2:0>8x}"
framesize = 8
frametype = "uint32_t"
_PrintARMUserStack(thread.task, cur_pc, cur_fp, framesize, frametype, frameformat, user_lib_info=user_lib_info)
@lldb_command('showthreaduserstack')
def ShowThreadUserStack(cmd_args=None):
""" Show user stack for a given thread.
Syntax: (lldb) showthreaduserstack <thread_ptr>
"""
if not cmd_args:
raise ArgumentError("Insufficient arguments")
thread = kern.GetValueFromAddress(ArgumentStringToInt(cmd_args[0]), 'thread *')
if kern.arch == "x86_64":
ShowX86UserStack(thread)
elif kern.arch == "arm":
ShowARMUserStack(thread)
return True
@lldb_command('showtaskuserstacks')
def ShowTaskUserStacks(cmd_args=None):
""" Print out the user stack for each thread in a task, followed by the user libraries.
Syntax: (lldb) showtaskuserstacks <task_t>
The format is compatible with CrashTracer. You can also use the speedtracer plugin as follows
(lldb) showtaskuserstacks <task_t> -p speedtracer
Note: the address ranges are approximations. Also the list may not be completely accurate. This command expects memory read failures
and hence will skip a library if unable to read information. Please use your good judgement and not take the output as accurate
"""
if not cmd_args:
raise ArgumentError("Insufficient arguments")
task = kern.GetValueFromAddress(cmd_args[0], 'task *')
pval = Cast(task.bsd_info, 'proc *')
crash_report_format_string = """\
Process: {pid: <10d}
Path: {path: <50s}
Identifier: {pname: <30s}
Version: ??? (???)
Code Type: {parch: <20s}
Parent Process: {ppname: >20s}[{ppid:d}]
Date/Time: {timest:s}.000 -0800
OS Version: {osversion: <20s}
Report Version: 8
Exception Type: n/a
Exception Codes: n/a
Crashed Thread: 0
Application Specific Information:
Synthetic crash log generated from Kernel userstacks
"""
user_lib_rex = re.compile("([0-9a-fx]+)\s-\s([0-9a-fx]+)\s+(.*?)\s", re.IGNORECASE|re.MULTILINE)
from datetime import datetime
ts = datetime.fromtimestamp(int(pval.p_start.tv_sec))
date_string = ts.strftime('%Y-%m-%d %H:%M:%S')
is_64 = False
if pval.p_flag & 0x4 :
is_64 = True
parch_s = ""
if kern.arch == "x86_64" or kern.arch == "i386":
osversion = "Mac OS X 10.8"
parch_s = "I386 (32 bit)"
if is_64:
parch_s = "X86-64 (Native)"
else:
parch_s = kern.arch
osversion = "iOS"
osversion += " ({:s})".format(kern.globals.osversion)
print crash_report_format_string.format(pid = pval.p_pid,
pname = pval.p_comm,
path = pval.p_comm,
ppid = pval.p_ppid,
ppname = GetProcNameForPid(pval.p_ppid),
timest = date_string,
parch = parch_s,
osversion = osversion
)
print "Binary Images:"
ShowTaskUserLibraries([hex(task)])
usertask_lib_info = [] for entry in ShowTaskUserLibraries.found_images:
arr = user_lib_rex.findall(entry[3])
if len(arr) == 0 :
continue
usertask_lib_info.append([int(arr[0][0],16), int(arr[0][1],16), str(arr[0][2]).strip()])
printthread_user_stack_ptr = ShowX86UserStack
if kern.arch == "arm":
printthread_user_stack_ptr = ShowARMUserStack
counter = 0
for thval in IterateQueue(task.threads, 'thread *', 'task_threads'):
print "\nThread {0:d} name:0x{1:x}\nThread {0:d}:".format(counter, thval)
counter += 1
try:
printthread_user_stack_ptr(thval, usertask_lib_info)
except Exception as exc_err:
print "Failed to show user stack for thread 0x{0:x}".format(thval)
if config['debug']:
raise exc_err
else:
print "Enable debugging ('(lldb) xnudebug debug') to see detailed trace."
return
def GetUserDataAsString(task, addr, size):
""" Get data from task's address space as a string of bytes
params:
task: task object from which to extract information
addr: int - start address to get data from.
size: int - no of bytes to read.
returns:
str - a stream of bytes. Empty string if read fails.
"""
err = lldb.SBError()
if GetConnectionProtocol() == "kdp":
kdp_pmap_addr = unsigned(addressof(kern.globals.kdp_pmap))
if not WriteInt64ToMemoryAddress(unsigned(task.map.pmap), kdp_pmap_addr):
debuglog("Failed to write in kdp_pmap from GetUserDataAsString.")
return ""
content = LazyTarget.GetProcess().ReadMemory(addr, size, err)
if not err.Success():
debuglog("Failed to read process memory. Error: " + err.description)
return ""
if not WriteInt64ToMemoryAddress(0, kdp_pmap_addr):
debuglog("Failed to reset in kdp_pmap from GetUserDataAsString.")
return ""
elif kern.arch in ['arm'] and long(size) < (2 * kern.globals.page_size):
range1_addr = long(addr)
range1_size = long(size)
if kern.StraddlesPage(range1_addr, range1_size):
range2_addr = long(kern.TruncPage(range1_addr + range1_size))
range2_size = long(range1_addr + range1_size - range2_addr)
range1_size = long(range2_addr - range1_addr)
else:
range2_addr = 0
range2_size = 0
range2_in_kva = 0
paddr_range1 = PmapWalk(task.map.pmap, range1_addr, vSILENT)
if not paddr_range1:
debuglog("Not mapped task 0x{:x} address 0x{:x}".format(task, addr))
return ""
range1_in_kva = kern.PhysToKernelVirt(paddr_range1)
content = LazyTarget.GetProcess().ReadMemory(range1_in_kva, range1_size, err)
if not err.Success():
raise RuntimeError("Failed to read process memory. Error: " + err.description)
if range2_addr:
paddr_range2 = PmapWalk(task.map.pmap, range2_addr, vSILENT)
if not paddr_range2:
debuglog("Not mapped task 0x{:x} address 0x{:x}".format(task, addr))
return ""
range2_in_kva = kern.PhysToKernelVirt(paddr_range2)
content += LazyTarget.GetProcess().ReadMemory(range1_in_kva, range1_size, err)
if not err.Success():
raise RuntimeError("Failed to read process memory. Error: " + err.description)
else:
raise NotImplementedError("GetUserDataAsString does not support this configuration")
return content
def _ExtractDataFromString(strdata, offset, data_type, length=0):
""" Extract specific data from string buffer
params:
strdata: str - string data give from GetUserDataAsString
offset: int - 0 based offset into the data.
data_type: str - defines what type to be read as. Supported values are:
'uint64_t', 'uint32_t', 'string'
length: int - used when data_type=='string'
returns
None - if extraction failed.
obj - based on what is requested in data_type
"""
unpack_str = "s"
if data_type == 'uint64_t':
length = 8
unpack_str = "Q"
elif data_type == "uint32_t":
length = 4
unpack_str = "I"
else:
unpack_str= "%ds" % length
data_len = len(strdata)
if offset > data_len or (offset + length) > data_len or offset < 0:
debuglog("Invalid arguments to _ExtractDataFromString.")
return 0
return struct.unpack(unpack_str, strdata[offset:(offset + length)])[0]
def GetPathForImage(task, path_address):
""" Maps 32 bytes at a time and packs as string
params:
task: obj - referencing task to read data from
path_address: int - address where the image path is stored
returns:
str - string path of the file. "" if failed to read.
"""
done = False
retval = ""
if path_address == 0:
done = True
while not done:
path_str_data = GetUserDataAsString(task, path_address, 32)
if len(path_str_data) == 0:
break
i = 0
while i < 32:
if ord(path_str_data[i]):
retval += path_str_data[i]
else:
break
i += 1
if i < 32:
done = True
else:
path_address += 32
return retval
def GetImageInfo(task, mh_image_address, mh_path_address, approx_end_address=None):
""" Print user library informaiton.
params:
task : obj referencing the task for which Image info printed
mh_image_address : int - address which has image info
mh_path_address : int - address which holds path name string
approx_end_address: int - address which lldbmacros think is end address.
returns:
str - string representing image info. "" if failure to read data.
"""
if approx_end_address:
image_end_load_address = int(approx_end_address) -1
else:
image_end_load_address = int(mh_image_address) + 0xffffffff
print_format = "0x{0:x} - 0x{1:x} {2: <50s} (??? - ???) <{3: <36s}> {4: <50s}"
mh_data = GetUserDataAsString(task, mh_image_address, 32)
if len(mh_data) == 0:
debuglog("unable to get userdata for task 0x{:x} img_addr 0x{:x} path_address 0x{:x}".format(
task, mh_image_address, mh_path_address))
return ""
mh_magic = _ExtractDataFromString(mh_data, (4 * 0), "uint32_t")
mh_cputype = _ExtractDataFromString(mh_data,(4 * 1), "uint32_t")
mh_cpusubtype = _ExtractDataFromString(mh_data,(4 * 2), "uint32_t")
mh_filetype = _ExtractDataFromString(mh_data,(4 * 3), "uint32_t")
mh_ncmds = _ExtractDataFromString(mh_data,(4 * 4), "uint32_t")
mh_sizeofcmds = _ExtractDataFromString(mh_data,(4 * 5), "uint32_t")
mh_flags = _ExtractDataFromString(mh_data,(4 * 6), "uint32_t")
if mh_magic == 0xfeedfacf:
mh_64 = True
lc_address = mh_image_address + 32
else:
mh_64 = False
lc_address = mh_image_address + 28
lc_idx = 0
uuid_data = 0
found_uuid_data = False
retval = None
while lc_idx < mh_ncmds:
lcmd_data = GetUserDataAsString(task, lc_address, 24)
lc_cmd = _ExtractDataFromString(lcmd_data, 4 * 0, "uint32_t")
lc_cmd_size = _ExtractDataFromString(lcmd_data, 4 * 1, "uint32_t")
lc_data = _ExtractDataFromString(lcmd_data, 4*2, "string", 16)
uuid_out_string = ""
path_out_string = ""
if lc_cmd == 0x1b:
uuid_data = [ord(x) for x in lc_data]
found_uuid_data = True
uuid_out_string = "{a[0]:02X}{a[1]:02X}{a[2]:02X}{a[3]:02X}-{a[4]:02X}{a[5]:02X}-{a[6]:02X}{a[7]:02X}-{a[8]:02X}{a[9]:02X}-{a[10]:02X}{a[11]:02X}{a[12]:02X}{a[13]:02X}{a[14]:02X}{a[15]:02X}".format(a=uuid_data)
path_out_string = GetPathForImage(task, mh_path_address)
path_base_name = path_out_string.split("/")[-1]
retval = print_format.format(mh_image_address, image_end_load_address, path_base_name, uuid_out_string, path_out_string)
elif lc_cmd == 0xe:
ShowTaskUserLibraries.exec_load_path = lc_address + _ExtractDataFromString(lcmd_data, 4*2, "uint32_t")
lc_address = lc_address + lc_cmd_size
lc_idx += 1
if not found_uuid_data:
path_out_string = GetPathForImage(task, mh_path_address)
path_base_name = path_out_string.split("/")[-1]
uuid_out_string = ""
retval = print_format.format(mh_image_address, image_end_load_address, path_base_name, uuid_out_string, path_out_string)
return retval
@static_var("found_images", []) @static_var("exec_load_path", 0)
@lldb_command("showtaskuserlibraries")
def ShowTaskUserLibraries(cmd_args=None):
""" Show binary images known by dyld in target task
For a given user task, inspect the dyld shared library state and print information about all Mach-O images.
Syntax: (lldb)showtaskuserlibraries <task_t>
Note: the address ranges are approximations. Also the list may not be completely accurate. This command expects memory read failures
and hence will skip a library if unable to read information. Please use your good judgement and not take the output as accurate
"""
if not cmd_args:
raise ArgumentError("Insufficient arguments")
ShowTaskUserLibraries.found_images = []
task = kern.GetValueFromAddress(cmd_args[0], 'task_t')
is_task_64 = int(task.t_flags) & 0x1
dyld_all_image_infos_address = unsigned(task.all_image_info_addr)
cur_data_offset = 0
if dyld_all_image_infos_address == 0:
print "No dyld shared library information available for task"
return False
vers_info_data = GetUserDataAsString(task, dyld_all_image_infos_address, 112)
version = _ExtractDataFromString(vers_info_data, cur_data_offset, "uint32_t")
cur_data_offset += 4
if version > 12:
print "Unknown dyld all_image_infos version number %d" % version
image_info_count = _ExtractDataFromString(vers_info_data, cur_data_offset, "uint32_t")
ShowTaskUserLibraries.exec_load_path = 0
if is_task_64:
image_info_size = 24
image_info_array_address = _ExtractDataFromString(vers_info_data, 8, "uint64_t")
dyld_load_address = _ExtractDataFromString(vers_info_data, 8*4, "uint64_t")
dyld_all_image_infos_address_from_struct = _ExtractDataFromString(vers_info_data, 8*13, "uint64_t")
else:
image_info_size = 12
image_info_array_address = _ExtractDataFromString(vers_info_data, 4*2, "uint32_t")
dyld_load_address = _ExtractDataFromString(vers_info_data, 4*5, "uint32_t")
dyld_all_image_infos_address_from_struct = _ExtractDataFromString(vers_info_data, 4*14, "uint32_t")
dyld_load_address = dyld_load_address + (dyld_all_image_infos_address - dyld_all_image_infos_address_from_struct)
i = 0
image_info_list = []
while i < image_info_count:
image_info_address = image_info_array_address + i * image_info_size
n_im_info_addr = None
img_data = ""
try:
img_data = GetUserDataAsString(task, image_info_address, image_info_size)
except Exception, e:
debuglog("Failed to read user data for task 0x{:x} addr 0x{:x}, exception {:s}".format(task, image_info_address, str(e)))
pass
if is_task_64:
image_info_addr = _ExtractDataFromString(img_data, 0, "uint64_t")
image_info_path = _ExtractDataFromString(img_data, 8, "uint64_t")
else:
image_info_addr = _ExtractDataFromString(img_data, 0, "uint32_t")
image_info_path = _ExtractDataFromString(img_data, 4, "uint32_t")
if image_info_addr :
image_info_list.append((image_info_addr, image_info_path))
i += 1
image_info_list.sort()
num_images_found = len(image_info_list)
for ii in range(num_images_found):
n_im_info_addr = dyld_load_address
if ii + 1 < num_images_found:
n_im_info_addr = image_info_list[ii+1][0]
image_info_addr = image_info_list[ii][0]
image_info_path = image_info_list[ii][1]
try:
image_print_s = GetImageInfo(task, image_info_addr, image_info_path, approx_end_address=n_im_info_addr)
if len(image_print_s) > 0:
print image_print_s
ShowTaskUserLibraries.found_images.append((image_info_addr, n_im_info_addr, image_info_path, image_print_s))
else:
debuglog("Failed to print image info for task 0x{:x} image_info 0x{:x}".format(task, image_info_addr))
except Exception,e:
if config['debug']:
raise e
if ShowTaskUserLibraries.exec_load_path != 0:
image_print_s = GetImageInfo(task, dyld_load_address, ShowTaskUserLibraries.exec_load_path)
if len(image_print_s) > 0:
print image_print_s
ShowTaskUserLibraries.found_images.append((dyld_load_address, dyld_load_address + 0xffffffff,
ShowTaskUserLibraries.exec_load_path, image_print_s))
else:
debuglog("Failed to print image for main executable for task 0x{:x} dyld_load_addr 0x{:x}".format(task, dyld_load_address))
return