Skip to content

fix: validate encryption context entry lengths #805

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
kiwigitops wants to merge 1 commit into
base: master
Choose a base branch
from
+21 −0
Open

fix: validate encryption context entry lengths #805

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
5 changes: 5 additions & 0 deletions src/aws_encryption_sdk/internal/formatting/encryption_context.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -71,7 +71,12 @@ def serialize_encryption_context(encryption_context):
"Cannot encode dictionary key or value using {}.".format(aws_encryption_sdk.internal.defaults.ENCODING)
)

max_value_length = aws_encryption_sdk.internal.defaults.MAX_BYTE_ARRAY_SIZE
for key, value in sorted(encryption_context_list, key=lambda x: x[0]):
if len(key) > max_value_length:
raise SerializationError("The encryption context contains a key that is too large.")
if len(value) > max_value_length:
raise SerializationError("The encryption context contains a value that is too large.")
serialized_context.extend(
struct.pack(
">H{key_size}sH{value_size}s".format(key_size=len(key), value_size=len(value)),
Expand Down
16 changes: 16 additions & 0 deletions test/unit/test_encryption_context.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -64,6 +64,22 @@ def test_serialize_encryption_context_too_large(self):
)
excinfo.match("The serialized context is too large")

def test_serialize_encryption_context_key_too_large(self):
oversized_key = "a" * (aws_encryption_sdk.internal.defaults.MAX_BYTE_ARRAY_SIZE + 1)
with pytest.raises(SerializationError) as excinfo:
aws_encryption_sdk.internal.formatting.encryption_context.serialize_encryption_context(
{oversized_key: "value"}
)
excinfo.match("The encryption context contains a key that is too large.")

def test_serialize_encryption_context_value_too_large(self):
oversized_value = "a" * (aws_encryption_sdk.internal.defaults.MAX_BYTE_ARRAY_SIZE + 1)
with pytest.raises(SerializationError) as excinfo:
aws_encryption_sdk.internal.formatting.encryption_context.serialize_encryption_context(
{"key": oversized_value}
)
excinfo.match("The encryption context contains a value that is too large.")

def test_serialize_encryption_context_unencodable(self):
"""Validate that the serialize_encryption_context
function behaves as expected when presented
Expand Down