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import sys
import traceback
from cffi import api as _api
sys.modules["ssl"] = None
sys.modules["_hashlib"] = None
_ffi = _api.FFI()
_ffi.cdef(
"""
void *malloc(size_t size);
void free(void *ptr);
void *realloc(void *ptr, size_t size);
int CRYPTO_set_mem_functions(
void *(*m)(size_t),void *(*r)(void *,size_t), void (*f)(void *));
int backtrace(void **buffer, int size);
char **backtrace_symbols(void *const *buffer, int size);
void backtrace_symbols_fd(void *const *buffer, int size, int fd);
"""
) # noqa
_api = _ffi.verify(
"""
#include <openssl/crypto.h>
#include <stdlib.h>
#include <execinfo.h>
""",
libraries=["crypto"],
)
C = _ffi.dlopen(None)
verbose = False
def log(s):
if verbose:
print(s)
def _backtrace():
buf = _ffi.new("void*[]", 64)
result = _api.backtrace(buf, len(buf))
strings = _api.backtrace_symbols(buf, result)
stack = [_ffi.string(strings[i]) for i in range(result)]
C.free(strings)
return stack
@_ffi.callback("void*(*)(size_t)")
def malloc(n):
memory = C.malloc(n)
python_stack = traceback.extract_stack(limit=3)
c_stack = _backtrace()
heap[memory] = [(n, python_stack, c_stack)]
log("malloc(%d) -> %s" % (n, memory))
return memory
@_ffi.callback("void*(*)(void*, size_t)")
def realloc(p, n):
memory = C.realloc(p, n)
old = heap.pop(p)
python_stack = traceback.extract_stack(limit=3)
c_stack = _backtrace()
old.append((n, python_stack, c_stack))
heap[memory] = old
log("realloc(0x%x, %d) -> %s" % (int(_ffi.cast("int", p)), n, memory))
return memory
@_ffi.callback("void(*)(void*)")
def free(p):
if p != _ffi.NULL:
C.free(p)
del heap[p]
log("free(0x%x)" % (int(_ffi.cast("int", p)),))
if _api.CRYPTO_set_mem_functions(malloc, realloc, free):
log("Enabled memory debugging")
heap = {}
else:
log("Failed to enable memory debugging")
heap = None
|
