certspotter/helpers.go

101 lines
2.8 KiB
Go

// Copyright (C) 2016 Opsmate, Inc.
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License, v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
//
// This software is distributed WITHOUT A WARRANTY OF ANY KIND.
// See the Mozilla Public License for details.
package certspotter
import (
"fmt"
"math/big"
"software.sslmate.com/src/certspotter/ct"
)
func IsPrecert(entry *ct.LogEntry) bool {
return entry.Leaf.TimestampedEntry.EntryType == ct.PrecertLogEntryType
}
type CertInfo struct {
TBS *TBSCertificate
Subject RDNSequence
SubjectParseError error
Issuer RDNSequence
IssuerParseError error
SANs []SubjectAltName
SANsParseError error
SerialNumber *big.Int
SerialNumberParseError error
Validity *CertValidity
ValidityParseError error
IsCA *bool
IsCAParseError error
IsPreCert bool
}
func MakeCertInfoFromTBS(tbs *TBSCertificate) *CertInfo {
info := &CertInfo{TBS: tbs}
info.Subject, info.SubjectParseError = tbs.ParseSubject()
info.Issuer, info.IssuerParseError = tbs.ParseIssuer()
info.SANs, info.SANsParseError = tbs.ParseSubjectAltNames()
info.SerialNumber, info.SerialNumberParseError = tbs.ParseSerialNumber()
info.Validity, info.ValidityParseError = tbs.ParseValidity()
info.IsCA, info.IsCAParseError = tbs.ParseBasicConstraints()
info.IsPreCert = len(tbs.GetExtension(oidExtensionCTPoison)) > 0
return info
}
func MakeCertInfoFromRawTBS(tbsBytes []byte) (*CertInfo, error) {
tbs, err := ParseTBSCertificate(tbsBytes)
if err != nil {
return nil, err
}
return MakeCertInfoFromTBS(tbs), nil
}
func MakeCertInfoFromRawCert(certBytes []byte) (*CertInfo, error) {
cert, err := ParseCertificate(certBytes)
if err != nil {
return nil, err
}
return MakeCertInfoFromRawTBS(cert.GetRawTBSCertificate())
}
func MakeCertInfoFromLogEntry(entry *ct.LogEntry) (*CertInfo, error) {
switch entry.Leaf.TimestampedEntry.EntryType {
case ct.X509LogEntryType:
return MakeCertInfoFromRawCert(entry.Leaf.TimestampedEntry.X509Entry)
case ct.PrecertLogEntryType:
return MakeCertInfoFromRawTBS(entry.Leaf.TimestampedEntry.PrecertEntry.TBSCertificate)
default:
return nil, fmt.Errorf("MakeCertInfoFromCTEntry: unknown CT entry type (neither X509 nor precert)")
}
}
func MatchesWildcard(dnsName string, pattern string) bool {
for len(pattern) > 0 {
if pattern[0] == '*' {
if len(dnsName) > 0 && dnsName[0] != '.' && MatchesWildcard(dnsName[1:], pattern) {
return true
}
pattern = pattern[1:]
} else {
if len(dnsName) == 0 || pattern[0] != dnsName[0] {
return false
}
pattern = pattern[1:]
dnsName = dnsName[1:]
}
}
return len(dnsName) == 0
}