ocsp: don't use iota for externally defined constants

Style fix: iota shouldn't be used for values that come from RFCs or
things that go over the wire or to disk.

Change-Id: Ib903ec1bce7e71ff81094db3de8d0b71e16f52f3
Reviewed-on: https://go-review.googlesource.com/c/crypto/+/564695
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Roland Shoemaker <roland@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Roland Shoemaker <roland@golang.org>

Author: bradfitz

ocsp/ocsp.go

@@ -279,21 +279,22 @@ func getOIDFromHashAlgorithm(target crypto.Hash) asn1.ObjectIdentifier {
 
 // This is the exposed reflection of the internal OCSP structures.
 
-// The status values that can be expressed in OCSP.  See RFC 6960.
+// The status values that can be expressed in OCSP. See RFC 6960.
+// These are used for the Response.Status field.
 const (
 	// Good means that the certificate is valid.
-	Good = iota
+	Good = 0
 	// Revoked means that the certificate has been deliberately revoked.
-	Revoked
+	Revoked = 1
 	// Unknown means that the OCSP responder doesn't know about the certificate.
-	Unknown
+	Unknown = 2
 	// ServerFailed is unused and was never used (see
 	// https://go-review.googlesource.com/#/c/18944). ParseResponse will
 	// return a ResponseError when an error response is parsed.
-	ServerFailed
+	ServerFailed = 3
 )
 
-// The enumerated reasons for revoking a certificate.  See RFC 5280.
+// The enumerated reasons for revoking a certificate. See RFC 5280.
 const (
 	Unspecified          = 0
 	KeyCompromise        = 1