client: add sysctl

src/rpcclient/rpcclient/client.py

@@ -25,6 +25,7 @@
     reply_protocol_message_t, dummy_block_t, SERVER_MAGIC_VERSION
 from rpcclient.symbol import Symbol
 from rpcclient.symbols_jar import SymbolsJar
+from rpcclient.sysctl import Sysctl
 
 tty_support = False
 try:
@@ -77,6 +78,7 @@ def __init__(self, sock, sysname: str, hostname: str, port: int = None):
         self.processes = Processes(self)
         self.network = Network(self)
         self.lief = Lief(self)
+        self.sysctl = Sysctl(self)
 
     def info(self):
         """ print information about current target """

src/rpcclient/rpcclient/sysctl.py

@@ -0,0 +1,41 @@
+import struct
+
+from rpcclient.exceptions import BadReturnValueError
+
+
+class Sysctl:
+    """ sysctl utils. read man page for sysctl(3) for more details """
+
+    def __init__(self, client):
+        self._client = client
+
+    def get_str(self, name: str) -> str:
+        """ equivalent of: sysctl <name> """
+        return self.get(name).strip(b'\x00').decode()
+
+    def get_int(self, name: str) -> int:
+        """ equivalent of: sysctl <name> """
+        return struct.unpack('<I', self.get(name))[0]
+
+    def set_int(self, name: str, value: int):
+        """ equivalent of: sysctl <name> -w value """
+        self.set(name, struct.pack('<I', value))
+
+    def set_str(self, name: str, value: str):
+        """ equivalent of: sysctl <name> -w value """
+        self.set(name, value.encode() + b'\x00')
+
+    def set(self, name: str, value: bytes):
+        """ equivalent of: sysctl <name> -w value """
+        if self._client.symbols.sysctlbyname(name, 0, 0, value, len(value)):
+            raise BadReturnValueError(f'sysctl() failed: {self._client.last_error}')
+
+    def get(self, name: str) -> bytes:
+        """ equivalent of: sysctl <name> """
+        oldval_len = 1024
+        with self._client.safe_malloc(8) as p_oldval_len:
+            p_oldval_len[0] = oldval_len
+            with self._client.safe_malloc(oldval_len) as oldval:
+                if self._client.symbols.sysctlbyname(name, oldval, p_oldval_len, 0, 0):
+                    raise BadReturnValueError(f'sysctl() failed: {self._client.last_error}')
+                return oldval.peek(p_oldval_len[0])