Fix issues related with debugging

examples/attach.py

@@ -5,7 +5,7 @@
 from pwn import *
 
 bash = process('/bin/bash')
-gdb.attach(bash, execute = '''
+gdb.attach(bash, gdbscript = '''
 p "hello from pwnlib"
 c
 ''')

examples/remote_gdb_debugging.py

@@ -8,7 +8,7 @@
 from pwn import *
 
 s = ssh(getpass.getuser(), '127.0.0.1', port = 22, keyfile = "~/.ssh/id_rsa")
-c = gdb.ssh_gdb(s, '/bin/sh', execute = '''
+c = gdb.ssh_gdb(s, '/bin/sh', gdbscript = '''
 p/x $pc
 c''')
 

pwnlib/gdb.py

@@ -404,9 +404,6 @@ def debug(args, gdbscript=None, exe=None, ssh=None, env=None, sysroot=None, **kw
     if isinstance(args, (int, tubes.process.process, tubes.ssh.ssh_channel)):
         log.error("Use gdb.attach() to debug a running process")
 
-    if env is None:
-        env = os.environ
-
     if isinstance(args, (bytes, six.text_type)):
         args = [args]
 
@@ -438,11 +435,11 @@ def debug(args, gdbscript=None, exe=None, ssh=None, env=None, sysroot=None, **kw
     if not which(args[0]):
         log.error("%s is not installed" % args[0])
 
-    exe = exe or which(orig_args[0])
-    if not exe:
-        log.error("%s does not exist" % orig_args[0])
-    else:
-        gdbscript = 'file "%s"\n%s' % (exe, gdbscript)
+    if not ssh:
+        exe = exe or which(orig_args[0])
+        if not (exe and os.path.exists(exe)):
+            log.error("%s does not exist" % exe)
+
 
     # Start gdbserver/qemu
     # (Note: We override ASLR here for the gdbserver process itself.)
@@ -660,9 +657,9 @@ def attach(target, gdbscript = None, exe = None, need_ptrace_scope = True, gdb_a
 
         shell = target.parent
 
-        tmpfile = shell.mktemp()
+        tmpfile = shell.mktemp().decode()
         gdbscript = 'shell rm %s\n%s' % (tmpfile, gdbscript)
-        shell.upload_data(context._encode(gdbscript), tmpfile)
+        shell.upload_data(gdbscript or '', tmpfile)
 
         cmd = ['ssh', '-C', '-t', '-p', str(shell.port), '-l', shell.user, shell.host]
         if shell.password:
@@ -671,7 +668,7 @@ def attach(target, gdbscript = None, exe = None, need_ptrace_scope = True, gdb_a
             cmd = ['sshpass', '-p', shell.password] + cmd
         if shell.keyfile:
             cmd += ['-i', shell.keyfile]
-        cmd += ['gdb -q %r %s -x "%s"' % (target.executable,
+        cmd += ['gdb -q %s %s -x "%s"' % (target.executable.decode(),
                                        target.pid,
                                        tmpfile)]
 
@@ -721,7 +718,7 @@ def findexe():
             exe_fn = adb.proc_exe
         exe = exe_fn(pid)
 
-    if not pid and not exe:
+    if not pid and not exe and not ssh:
         log.error('could not find target process')
 
     if exe:
@@ -901,7 +898,7 @@ def find_module_addresses(binary, ssh=None, ulimit=False):
         """ % entry)
         gdb.clean(2)
         gdb.sendline('info sharedlibrary')
-        lines = gdb.recvrepeat(2)
+        lines = context._decode(gdb.recvrepeat(2))
 
         for line in lines.splitlines():
             m = expr.match(line)

pwnlib/tubes/process.py

@@ -242,10 +242,6 @@ def __init__(self, argv = None,
         if not shell:
             executable, argv, env = self._validate(cwd, executable, argv, env)
 
-        # Permit invocation as process('sh') and process(['sh'])
-        if isinstance(argv, (bytes, six.text_type)):
-            argv = [argv]
-
         # Avoid the need to have to deal with the STDOUT magic value.
         if stderr is STDOUT:
             stderr = stdout
@@ -308,13 +304,15 @@ def __init__(self, argv = None,
             # and binfmt is not installed (e.g. when running on
             # Travis CI), re-try with qemu-XXX if we get an
             # 'Exec format error'.
-            prefixes = [([], executable)]
-            executables = [executable]
+            prefixes = [([], self.executable)]
             exception = None
 
             for prefix, executable in prefixes:
                 try:
-                    self.proc = subprocess.Popen(args = prefix + argv,
+                    args = argv
+                    if (prefix):
+                        args = prefix + args
+                    self.proc = subprocess.Popen(args = args,
                                                  shell = shell,
                                                  executable = executable,
                                                  cwd = cwd,
@@ -509,11 +507,14 @@ def _validate(self, cwd, executable, argv, env):
         # - Must be a list/tuple of strings
         # - Each string must not contain '\x00'
         #
-        if isinstance(argv, (bytes, six.text_type)):
+        if isinstance(argv, (six.text_type, six.binary_type)):
             argv = [argv]
 
-        if not all(isinstance(arg, (bytes, six.text_type)) for arg in argv):
-            self.error("argv must be strings: %r" % argv)
+        if not isinstance(argv, (list, tuple)):
+            self.error('argv must be a list or tuple: %r' % argv)
+
+        if not all(isinstance(arg, (six.text_type, six.binary_type)) for arg in argv):
+            self.error("argv must be strings or bytes: %r" % argv)
 
         # Create a duplicate so we can modify it
         argv = list(argv or [])

pwnlib/tubes/ssh.py

@@ -21,7 +21,6 @@
 from pwnlib.log import getLogger
 from pwnlib.term import text
 from pwnlib.timeout import Timeout
-from pwnlib.tubes.process import process
 from pwnlib.tubes.sock import sock
 from pwnlib.util import hashes
 from pwnlib.util import misc
@@ -774,7 +773,7 @@ def process(self, argv=None, executable=None, tty=True, cwd=None, env=None, time
             >>> s.process(['LOLOLOL\x00', '/proc/self/cmdline'], executable='cat').recvall()
             b'LOLOLOL\x00/proc/self/cmdline\x00'
             >>> sh = s.process(executable='/bin/sh')
-            >>> sh.pid in pidof('sh') # doctest: +SKIP
+            >>> str(sh.pid).encode() in s.pidof('sh') # doctest: +SKIP
             True
             >>> s.process(['pwd'], cwd='/tmp').recvall()
             b'/tmp\n'
@@ -823,11 +822,17 @@ def process(self, argv=None, executable=None, tty=True, cwd=None, env=None, time
         if not isinstance(argv, (list, tuple)):
             self.error('argv must be a list or tuple')
 
+        if not all(isinstance(arg, (six.text_type, six.binary_type)) for arg in argv):
+            self.error("argv must be strings or bytes: %r" % argv)
+
         if shell:
             if len(argv) != 1:
                 self.error('Cannot provide more than 1 argument if shell=True')
             argv = ['/bin/sh', '-c'] + argv
 
+        # Create a duplicate so we can modify it
+        argv = list(argv or [])
+
         # Python doesn't like when an arg in argv contains '\x00'
         # -> execve() arg 2 must contain only strings
         for i, oarg in enumerate(argv):
@@ -860,12 +865,8 @@ def process(self, argv=None, executable=None, tty=True, cwd=None, env=None, time
         # Validate, since failures on the remote side will suck.
         if not isinstance(executable, (six.text_type, six.binary_type)):
             self.error("executable / argv[0] must be a string: %r" % executable)
-        if not isinstance(argv, (list, tuple)):
-            self.error("argv must be a list or tuple: %r" % argv)
         if env is not None and not isinstance(env, dict) and env != os.environ:
             self.error("env must be a dict: %r" % env)
-        if not all(isinstance(s, (six.text_type, six.binary_type)) for s in argv):
-            self.error("argv must only contain strings: %r" % argv)
 
         # Allow passing in sys.stdin/stdout/stderr objects
         handles = {sys.stdin: 0, sys.stdout:1, sys.stderr:2}
@@ -1328,7 +1329,7 @@ def _libs_remote(self, remote):
             self.error('Unable to find libraries for %r' % remote)
             return {}
 
-        return misc.parse_ldd_output(data)
+        return misc.parse_ldd_output(context._decode(data))
 
     def _get_fingerprint(self, remote):
         cmd = '(sha256 || sha256sum || openssl sha256) 2>/dev/null < '
@@ -1553,6 +1554,7 @@ def upload_data(self, data, remote):
             >>> print(open('/tmp/upload_bar').read())
             Hello, world
         """
+        data = context._encode(data)
         # If a relative path was provided, prepend the cwd
         if os.path.normpath(remote) == os.path.basename(remote):
             remote = os.path.join(self.cwd, remote)
@@ -1700,7 +1702,7 @@ def libs(self, remote, directory = None):
 
         libs = self._libs_remote(remote)
 
-        remote = self.readlink('-f',remote).strip()
+        remote = context._decode(self.readlink('-f',remote).strip())
         libs[remote] = 0
 
         if directory == None:

pwnlib/util/cyclic.py

@@ -218,6 +218,7 @@ def cyclic_find(subseq, alphabet = None, n = None):
 
     if isinstance(subseq, six.integer_types):
         subseq = packing.pack(subseq, bytes=n)
+    subseq = context._encode(subseq)
 
     if len(subseq) != n:
         log.warn_once("cyclic_find() expects %i-byte subsequences by default, you gave %r\n"\