1 files changed, 37 insertions, 0 deletions
diff --git a/pyasn1/error.py b/pyasn1/error.py
index 85a31ff..08ec1b3 100644
--- a/pyasn1/error.py
+++ b/pyasn1/error.py
@@ -12,7 +12,36 @@ class PyAsn1Error(Exception):
     `PyAsn1Error` is the base exception class (based on
     :class:`Exception`) that represents all possible ASN.1 related
     errors.
+
+    Parameters
+    ----------
+    args:
+        Opaque positional parameters
+
+    Keyword Args
+    ------------
+    kwargs:
+        Opaque keyword parameters
+
     """
+    def __init__(self, *args, **kwargs):
+        self._args = args
+        self._kwargs = kwargs
+
+    @property
+    def context(self):
+        """Return exception context
+
+        When exception object is created, the caller can supply some opaque
+        context for the upper layers to better understand the cause of the
+        exception.
+
+        Returns
+        -------
+        : :py:class:`dict`
+            Dict holding context specific data
+        """
+        return self._kwargs.get('context', {})
 
 
 class ValueConstraintError(PyAsn1Error):
@@ -34,6 +63,14 @@ class SubstrateUnderrunError(PyAsn1Error):
     """
 
 
+class EndOfStreamError(SubstrateUnderrunError):
+    """ASN.1 data structure deserialization error
+
+    The `EndOfStreamError` exception indicates the condition of the input
+    stream has been closed.
+    """
+
+
 class UnsupportedSubstrateError(PyAsn1Error):
     """Unsupported substrate type to parse as ASN.1 data."""