Outbound group session support in the python wrappers

1 files changed, 83 insertions, 0 deletions

diff --git a/python/olm/outbound_group_session.py b/python/olm/outbound_group_session.py
new file mode 100644
index 0000000..6182647
--- /dev/null
+++ b/python/olm/outbound_group_session.py
@@ -0,0 +1,83 @@
+import json
+
+from ._base import *
+
+lib.olm_outbound_group_session_size.argtypes = []
+lib.olm_outbound_group_session_size.restype = c_size_t
+
+lib.olm_outbound_group_session.argtypes = [c_void_p]
+lib.olm_outbound_group_session.restype = c_void_p
+
+lib.olm_outbound_group_session_last_error.argtypes = [c_void_p]
+lib.olm_outbound_group_session_last_error.restype = c_char_p
+
+def outbound_group_session_errcheck(res, func, args):
+    if res == ERR:
+        raise OlmError("%s: %s" % (
+            func.__name__, lib.olm_outbound_group_session_last_error(args[0])
+        ))
+    return res
+
+
+def outbound_group_session_function(func, *types):
+    func.argtypes = (c_void_p,) + types
+    func.restypes = c_size_t
+    func.errcheck = outbound_group_session_errcheck
+
+
+outbound_group_session_function(
+    lib.olm_pickle_outbound_group_session, c_void_p, c_size_t, c_void_p, c_size_t
+)
+outbound_group_session_function(
+    lib.olm_unpickle_outbound_group_session, c_void_p, c_size_t, c_void_p, c_size_t
+)
+
+outbound_group_session_function(lib.olm_init_outbound_group_session_random_length)
+outbound_group_session_function(lib.olm_init_outbound_group_session, c_void_p, c_size_t)
+outbound_group_session_function(lib.olm_group_encrypt_message_length, c_size_t)
+outbound_group_session_function(lib.olm_group_encrypt,
+    c_void_p, c_size_t,  # Plaintext
+    c_void_p, c_size_t,  # Message
+)
+
+
+class OutboundGroupSession(object):
+    def __init__(self):
+        self.buf = create_string_buffer(lib.olm_outbound_group_session_size())
+        self.ptr = lib.olm_outbound_group_session(self.buf)
+
+        random_length = lib.olm_init_outbound_group_session_random_length(self.ptr)
+        random = read_random(random_length)
+        random_buffer = create_string_buffer(random)
+        lib.olm_init_outbound_group_session(self.ptr, random_buffer, random_length)
+
+    def pickle(self, key):
+        key_buffer = create_string_buffer(key)
+        pickle_length = lib.olm_pickle_outbound_group_session_length(self.ptr)
+        pickle_buffer = create_string_buffer(pickle_length)
+        lib.olm_pickle_outbound_group_session(
+            self.ptr, key_buffer, len(key), pickle_buffer, pickle_length
+        )
+        return pickle_buffer.raw
+
+    def unpickle(self, key, pickle):
+        key_buffer = create_string_buffer(key)
+        pickle_buffer = create_string_buffer(pickle)
+        lib.olm_unpickle_outbound_group_session(
+            self.ptr, key_buffer, len(key), pickle_buffer, len(pickle)
+        )
+
+    def encrypt(self, plaintext):
+        message_length = lib.olm_group_encrypt_message_length(
+            self.ptr, len(plaintext)
+        )
+        message_buffer = create_string_buffer(message_length)
+
+        plaintext_buffer = create_string_buffer(plaintext)
+
+        lib.olm_group_encrypt(
+            self.ptr,
+            plaintext_buffer, len(plaintext),
+            message_buffer, message_length,
+        )
+        return message_buffer.raw