You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
60 lines
2.2 KiB
60 lines
2.2 KiB
7 years ago
|
From f9702eabc568679f48ea5d0bc7be073582cc52ad Mon Sep 17 00:00:00 2001
|
||
|
|
From: Greg Hudson <ghudson@mit.edu>
|
||
|
|
Date: Thu, 4 May 2017 17:03:35 -0400
|
||
|
|
Subject: [PATCH] Add y2038 documentation
|
||
|
|
|
||
|
|
ticket: 8352
|
||
|
|
(cherry picked from commit 85d64c43dbf7a7faa56a1999494cdfa49e8bd2c9)
|
||
|
|
---
|
||
|
|
doc/appdev/index.rst | 1 +
|
||
|
|
doc/appdev/y2038.rst | 28 ++++++++++++++++++++++++++++
|
||
|
|
2 files changed, 29 insertions(+)
|
||
|
|
create mode 100644 doc/appdev/y2038.rst
|
||
|
|
|
||
|
|
diff --git a/doc/appdev/index.rst b/doc/appdev/index.rst
|
||
|
|
index 3d62045ca..961bb1e9e 100644
|
||
|
|
--- a/doc/appdev/index.rst
|
||
|
|
+++ b/doc/appdev/index.rst
|
||
|
|
@@ -5,6 +5,7 @@ For application developers
|
||
|
|
:maxdepth: 1
|
||
|
|
|
||
|
|
gssapi.rst
|
||
|
|
+ y2038.rst
|
||
|
|
h5l_mit_apidiff.rst
|
||
|
|
init_creds.rst
|
||
|
|
princ_handle.rst
|
||
|
|
diff --git a/doc/appdev/y2038.rst b/doc/appdev/y2038.rst
|
||
|
|
new file mode 100644
|
||
|
|
index 000000000..bc4122dad
|
||
|
|
--- /dev/null
|
||
|
|
+++ b/doc/appdev/y2038.rst
|
||
|
|
@@ -0,0 +1,28 @@
|
||
|
|
+Year 2038 considerations for uses of krb5_timestamp
|
||
|
|
+===================================================
|
||
|
|
+
|
||
|
|
+POSIX time values, which measure the number of seconds since January 1
|
||
|
|
+1970, will exceed the maximum value representable in a signed 32-bit
|
||
|
|
+integer in January 2038. This documentation describes considerations
|
||
|
|
+for consumers of the MIT krb5 libraries.
|
||
|
|
+
|
||
|
|
+Applications or libraries which use libkrb5 and consume the timestamps
|
||
|
|
+included in credentials or other structures make use of the
|
||
|
|
+:c:type:`krb5_timestamp` type. For historical reasons, krb5_timestamp
|
||
|
|
+is a signed 32-bit integer, even on platforms where a larger type is
|
||
|
|
+natively used to represent time values. To behave properly for time
|
||
|
|
+values after January 2038, calling code should cast krb5_timestamp
|
||
|
|
+values to uint32_t, and then to time_t::
|
||
|
|
+
|
||
|
|
+ (time_t)(uint32_t)timestamp
|
||
|
|
+
|
||
|
|
+Used in this way, krb5_timestamp values can represent time values up
|
||
|
|
+until February 2106, provided that the platform uses a 64-bit or
|
||
|
|
+larger time_t type. This usage will also remain safe if a later
|
||
|
|
+version of MIT krb5 changes krb5_timestamp to an unsigned 32-bit
|
||
|
|
+integer.
|
||
|
|
+
|
||
|
|
+The GSSAPI only uses representations of time intervals, not absolute
|
||
|
|
+times. Callers of the GSSAPI should require no changes to behave
|
||
|
|
+correctly after January 2038, provided that they use MIT krb5 release
|
||
|
|
+1.16 or later.
|