Add set_time_soft to replace get_time

The SetTime command supports two modes: set the time without checking
the currently set time, or verify that the currently set time is not
zero and not larger than the new time (see cmd_set_time(uint8_t*,
uint8_t*) in src/keyboard/report_protocol.c, lines 678--710, in the
Nitrokey Pro firmware).

NitrokeyManager called these two modes set_time(uint64_t) and
get_time(uint64_t), which is highly misleading -- the command does never
get the time.  Furthermore, the get_time method per default calls the
command with the time zero, which will always result in an error.

The C API has the methods NK_totp_set_time(uint64_t) and
NK_totp_get_time().  NK_totp_get_time() calls get_time(uint64_t) with
the time zero, leading to an error, and is therefore useless.

This patch proposes a new wording.  While it would make sense to call
the first mode “reset” and the second mode “set”, this would break
compatibility.  Therefore, new methods set_time_soft(uint64_t) and
NK_totp_set_time_soft(uint64_t) are introduced to represent the
difference between a hard and a soft setting of the time.

The old methods, get_time(uint64_t) and NK_totp_get_time(), are not
removed but marked as deprecated.  They should be removed in an upcoming
major release.

1 files changed, 7 insertions, 0 deletions

diff --git a/NK_C_API.cc b/NK_C_API.cc
index 00694c7..c679597 100644
--- a/NK_C_API.cc
+++ b/NK_C_API.cc
@@ -358,6 +358,13 @@ extern "C" {
 		});
 	}
 
+	NK_C_API int NK_totp_set_time_soft(uint64_t time) {
+		auto m = NitrokeyManager::instance();
+		return get_without_result([&]() {
+			m->set_time_soft(time);
+		});
+        }
+
 	NK_C_API int NK_totp_get_time() {
 		auto m = NitrokeyManager::instance();
 		return get_without_result([&]() {