group_cipher.h

#ifndef GROUP_CIPHER_H
#define GROUP_CIPHER_H

#include <stdint.h>
#include <stddef.h>
#include "signal_protocol_types.h"

#ifdef __cplusplus
extern "C" {
#endif

/*
 * The main entry point for Signal Protocol group encrypt/decrypt operations.
 *
 * Once a session has been established with group_session_builder and a
 * sender_key_distribution_message has been distributed to each member of
 * the group, this class can be used for all subsequent encrypt/decrypt
 * operations within that session (i.e. until group membership changes).
 */

int group_cipher_create(group_cipher **cipher,
        signal_protocol_store_context *store, const signal_protocol_sender_key_name *sender_key_id,
        signal_context *global_context);

void group_cipher_set_user_data(group_cipher *cipher, void *user_data);

void *group_cipher_get_user_data(group_cipher *cipher);

void group_cipher_set_decryption_callback(group_cipher *cipher,
        int (*callback)(group_cipher *cipher, signal_buffer *plaintext, void *decrypt_context));

int group_cipher_encrypt(group_cipher *cipher,
        const uint8_t *padded_plaintext, size_t padded_plaintext_len,
        ciphertext_message **encrypted_message);

int group_cipher_decrypt(group_cipher *cipher,
        sender_key_message *ciphertext, void *decrypt_context,
        signal_buffer **plaintext);

void group_cipher_free(group_cipher *cipher);

#ifdef __cplusplus
}
#endif

#endif /* GROUP_CIPHER_H */