1 files changed, 139 insertions, 0 deletions
diff --git a/libs/libaxolotl/src/key_helper.h b/libs/libaxolotl/src/key_helper.h
new file mode 100644
index 0000000000..1a7175b620
--- /dev/null
+++ b/libs/libaxolotl/src/key_helper.h
@@ -0,0 +1,139 @@
+#ifndef KEY_HELPER_H
+#define KEY_HELPER_H
+
+#include <stdint.h>
+#include "axolotl_types.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+* Generate an identity key pair.  Clients should only do this once,
+* at install time.
+*
+* @param key_pair the generated identity key pair
+* @return 0 on success, or negative on failure
+*/
+int axolotl_key_helper_generate_identity_key_pair(ratchet_identity_key_pair **key_pair, axolotl_context *global_context);
+
+/**
+ * Generate a registration ID.  Clients should only do this once,
+ * at install time.
+ *
+ * @param registration_id set to the generated registration ID
+ * @param extendedRange By default (0), the generated registration
+ *                      ID is sized to require the minimal possible protobuf
+ *                      encoding overhead. Specify true (1) if the caller needs
+ *                      the full range of MAX_INT at the cost of slightly
+ *                      higher encoding overhead.
+ * @return 0 on success, or negative on failure
+ */
+int axolotl_key_helper_generate_registration_id(uint32_t *registration_id, int extended_range, axolotl_context *global_context);
+
+/**
+ * Generate a random number bounded by the provided maximum
+ *
+ * @param value set to the next random number
+ * @param max the maximum value of the random number
+ * @return 0 on success, or negative on failure
+ */
+int axolotl_key_helper_get_random_sequence(int *value, int max, axolotl_context *global_context);
+
+/**
+ * Generate a list of PreKeys.  Clients should do this at install time, and
+ * subsequently any time the list of PreKeys stored on the server runs low.
+ *
+ * Pre key IDs are shorts, so they will eventually be repeated.  Clients should
+ * store pre keys in a circular buffer, so that they are repeated as infrequently
+ * as possible.
+ *
+ * When finished with this list, the caller should free it by calling
+ * axolotl_key_helper_key_list_free().
+ *
+ * @param head pointer to the head of the key list
+ * @param start the starting pre key ID, inclusive.
+ * @param count the number of pre keys to generate.
+ * @return 0 on success, or negative on failure
+ */
+int axolotl_key_helper_generate_pre_keys(axolotl_key_helper_pre_key_list_node **head,
+        unsigned int start, unsigned int count,
+        axolotl_context *global_context);
+
+/**
+ * Get the pre key element for the current node in the key list.
+ *
+ * @param current list node
+ * @return pre key element
+ */
+session_pre_key *axolotl_key_helper_key_list_element(const axolotl_key_helper_pre_key_list_node *node);
+
+/**
+ * Get the next element in the ket list.
+ *
+ * @param current list node
+ * @return next list node, or 0 if at the end of the list
+ */
+axolotl_key_helper_pre_key_list_node *axolotl_key_helper_key_list_next(const axolotl_key_helper_pre_key_list_node *node);
+
+/**
+ * Free the key list.
+ *
+ * @param head pointer to the head of the list to free
+ */
+void axolotl_key_helper_key_list_free(axolotl_key_helper_pre_key_list_node *head);
+
+/**
+ * Generate the last resort pre key.  Clients should do this only once, at
+ * install time, and durably store it for the length of the install.
+ *
+ * @param pre_key set to the generated pre key
+ * @return 0 on success, or negative on failure
+ */
+int axolotl_key_helper_generate_last_resort_pre_key(session_pre_key **pre_key, axolotl_context *global_context);
+
+/**
+ * Generate a signed pre key
+ *
+ * @param signed_pre_key set to the generated pre key
+ * @param identity_key_pair the local client's identity key pair.
+ * @param signed_pre_key_id the pre key ID to assign the generated signed pre key
+ * @param timestamp the current time in milliseconds since the UNIX epoch
+ *
+ * @return 0 on success, or negative on failure
+ */
+int axolotl_key_helper_generate_signed_pre_key(session_signed_pre_key **signed_pre_key,
+        const ratchet_identity_key_pair *identity_key_pair,
+        uint32_t signed_pre_key_id,
+        uint64_t timestamp,
+        axolotl_context *global_context);
+
+/*
+ * Generate a sender signing key pair
+ *
+* @param key_pair the generated key pair
+* @return 0 on success, or negative on failure
+ */
+int axolotl_key_helper_generate_sender_signing_key(ec_key_pair **key_pair, axolotl_context *global_context);
+
+/*
+ * Generate a sender key
+ *
+ * @param key_buffer buffer to be allocated and populated with the result
+ * @return 0 on success, or negative on failure
+ */
+int axolotl_key_helper_generate_sender_key(axolotl_buffer **key_buffer, axolotl_context *global_context);
+
+/*
+ * Generate a sender key ID
+ *
+ * @param key_id assigned to the generated ID
+ * @return 0 on success, or negative on failure
+ */
+int axolotl_key_helper_generate_sender_key_id(uint32_t *key_id, axolotl_context *global_context);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* KEY_HELPER_H */