ASN1_GENERALIZEDTIME and ASN1_UTCTIME may be specified using offsets,
even though that's not supported within certificates. [davidben: This
commit message seems off as crypto/x509 does not reject them. It merely
has a comment telling you that it's doing it wrong.]
To convert the offset time back to GMT, the offsets are supposed to be
subtracted, not added. e.g. 1759-0500 == 2359+0100 == 2259Z.
(Imported from upstream's d2335f30970ed3edc1c7c11700ab7f34396cf086.)
Change-Id: Id0d4c5b650e77db3b04b15e66b069807f6f31266
Reviewed-on: https://boringssl-review.googlesource.com/15834
Commit-Queue: David Benjamin <davidben@google.com>
Commit-Queue: Steven Valdez <svaldez@google.com>
Reviewed-by: Steven Valdez <svaldez@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>