week06

env/lib/python3.12/site-packages/pyshark/packet/fields.py

@@ -0,0 +1,115 @@
+import binascii
+import typing
+
+from pyshark.packet.common import Pickleable, SlotsPickleable
+
+
+class LayerField(SlotsPickleable):
+    """Holds all data about a field of a layer, both its actual value and its name and nice representation."""
+
+    # Note: We use this object with slots and not just a dict because
+    # it's much more memory-efficient (cuts about a third of the memory).
+    __slots__ = ['name', 'showname', 'raw_value', 'show', 'hide', 'pos', 'size', 'unmaskedvalue']
+
+    def __init__(self, name=None, showname=None, value=None, show=None, hide=None, pos=None, size=None, unmaskedvalue=None):
+        self.name = name
+        self.showname = showname
+        self.raw_value = value
+        self.show = show
+        self.pos = pos
+        self.size = size
+        self.unmaskedvalue = unmaskedvalue
+
+        if hide and hide == 'yes':
+            self.hide = True
+        else:
+            self.hide = False
+
+    def __repr__(self):
+        return f'<LayerField {self.name}: {self.get_default_value()}>'
+
+    def get_default_value(self) -> str:
+        """Gets the best 'value' string this field has."""
+        val = self.show
+        if not val:
+            val = self.raw_value
+        if not val:
+            val = self.showname
+        return val
+
+    @property
+    def showname_value(self) -> typing.Union[str, None]:
+        """The "pretty value" (as displayed by Wireshark) of the field."""
+        if self.showname and ': ' in self.showname:
+            return self.showname.split(': ', 1)[1]
+        return None
+
+    @property
+    def showname_key(self) -> typing.Union[str, None]:
+        """The "pretty name" (as displayed by Wireshark) of the field."""
+        if self.showname and ': ' in self.showname:
+            return self.showname.split(': ', 1)[0]
+        return None
+
+    @property
+    def binary_value(self) -> bytes:
+        """Converts this field to binary (assuming it's a binary string)"""
+        str_raw_value = str(self.raw_value)
+        if len(str_raw_value) % 2 == 1:
+            str_raw_value = '0' + str_raw_value
+
+        return binascii.unhexlify(str_raw_value)
+
+    @property
+    def int_value(self) -> int:
+        """Returns the int value of this field (assuming it's represented as a decimal integer)."""
+        return int(self.raw_value)
+
+    @property
+    def hex_value(self) -> int:
+        """Returns the int value of this field if it's in base 16
+
+        (either as a normal number or in a "0xFFFF"-style hex value)
+        """
+        return int(self.raw_value, 16)
+
+    base16_value = hex_value
+
+
+class LayerFieldsContainer(str, Pickleable):
+    """An object which contains one or more fields (of the same name).
+
+    When accessing member, such as showname, raw_value, etc. the appropriate member of the main (first) field saved
+    in this container will be shown.
+    """
+
+    def __new__(cls, main_field, *args, **kwargs):
+        if hasattr(main_field, 'get_default_value'):
+            obj = str.__new__(cls, main_field.get_default_value(), *args, **kwargs)
+        else:
+            obj = str.__new__(cls, main_field, *args, **kwargs)
+        obj.fields = [main_field]
+        return obj
+
+    def __dir__(self):
+        return dir(type(self)) + list(self.__dict__.keys()) + dir(self.main_field)
+
+    def add_field(self, field):
+        self.fields.append(field)
+
+    @property
+    def all_fields(self):
+        """Returns all fields in a list, the main field followed by the alternate fields."""
+        return self.fields
+
+    @property
+    def main_field(self):
+        return self.fields[0]
+
+    @property
+    def alternate_fields(self):
+        """Return the alternate values of this field containers (non-main ones)."""
+        return self.fields[1:]
+
+    def __getattr__(self, item):
+        return getattr(self.main_field, item)