From: Adam Langley <agl@golang.org>
Date: Mon, 5 Mar 2012 16:31:24 +0000 (-0500)
Subject: encoding/asn1: handle UTCTime before the year 2000
X-Git-Tag: weekly.2012-03-13~237
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=6aed6130309c5567015069599712671a99444fd1;p=gostls13.git

encoding/asn1: handle UTCTime before the year 2000

UTCTime only has a two digit date field and year values from 50 should
be 1950, not 2050.

R=golang-dev, r, rsc
CC=golang-dev
https://golang.org/cl/5729063
---

diff --git a/src/pkg/encoding/asn1/asn1.go b/src/pkg/encoding/asn1/asn1.go
index 4d1ae38c4e..3bf81a68cf 100644
--- a/src/pkg/encoding/asn1/asn1.go
+++ b/src/pkg/encoding/asn1/asn1.go
@@ -250,10 +250,14 @@ func parseBase128Int(bytes []byte, initOffset int) (ret, offset int, err error)
 func parseUTCTime(bytes []byte) (ret time.Time, err error) {
 	s := string(bytes)
 	ret, err = time.Parse("0601021504Z0700", s)
-	if err == nil {
-		return
+	if err != nil {
+		ret, err = time.Parse("060102150405Z0700", s)
 	}
-	ret, err = time.Parse("060102150405Z0700", s)
+	if err == nil && ret.Year() >= 2050 {
+		// UTCTime only encodes times prior to 2050. See https://tools.ietf.org/html/rfc5280#section-4.1.2.5.1
+		ret = ret.AddDate(-100, 0, 0)
+	}
+
 	return
 }