From 503b156ec646f7692397c8708af7e29691a9533e Mon Sep 17 00:00:00 2001
From: "Matt Johnson (AZURE)" <mattjoh@microsoft.com>
Date: Thu, 29 Aug 2019 16:11:05 -0700
Subject: [PATCH] Prevent cert creation failure on leap day

---
 cups/tls-sspi.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/cups/tls-sspi.c b/cups/tls-sspi.c
index 6e3c03b9ec..1306b9a746 100644
--- a/cups/tls-sspi.c
+++ b/cups/tls-sspi.c
@@ -1968,6 +1968,11 @@ http_sspi_make_credentials(
   GetSystemTime(&et);
   et.wYear += years;
 
+  // If today is February 29th, and the above addition operation results in a year that is *not* a leap year,
+  // then use February 28th instead.  Otherwise CertCreateSelfSignCertificate would fail.
+  bool isLeapYear = et.wYear % 4 == 0 && (et.wYear % 100 != 0 || et.wYear % 400 == 0);
+  et.wDay = et.wMonth == 2 && et.wDay == 29 && !isLeapYear ? 28 : et.wDay;
+
   ZeroMemory(&exts, sizeof(exts));
 
   createdContext = CertCreateSelfSignCertificate(hProv, &sib, 0, &kpi, NULL, NULL, &et, &exts);