1// Copyright (c) 2011 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5#ifndef NET_BASE_ASN1_UTIL_H_ 6#define NET_BASE_ASN1_UTIL_H_ 7#pragma once 8 9#include "base/string_piece.h" 10 11namespace net { 12 13namespace asn1 { 14 15// These are the DER encodings of the tag byte for ASN.1 objects. 16static const unsigned kINTEGER = 0x02; 17static const unsigned kOID = 0x06; 18static const unsigned kSEQUENCE = 0x30; 19 20// These are flags that can be ORed with the above tag numbers. 21static const unsigned kContextSpecific = 0x80; 22static const unsigned kCompound = 0x20; 23 24// ParseElement parses a DER encoded ASN1 element from |in|, requiring that 25// it have the given |tag_value|. It returns true on success. The following 26// limitations are imposed: 27// 1) tag numbers > 31 are not permitted. 28// 2) lengths > 65535 are not permitted. 29// On successful return: 30// |in| is advanced over the element 31// |out| contains the element, including the tag and length bytes. 32// |out_header_len| contains the length of the tag and length bytes in |out|. 33bool ParseElement(base::StringPiece* in, 34 unsigned tag_value, 35 base::StringPiece* out, 36 unsigned *out_header_len); 37 38// GetElement performs the same actions as ParseElement, except that the header 39// bytes are not included in the output. 40bool GetElement(base::StringPiece* in, 41 unsigned tag_value, 42 base::StringPiece* out); 43 44 45// ExtractSPKIFromDERCert parses the DER encoded certificate in |cert| and 46// extracts the bytes of the SubjectPublicKeyInfo. On successful return, 47// |spki_out| is set to contain the SPKI, pointing into |cert|. 48bool ExtractSPKIFromDERCert(base::StringPiece cert, 49 base::StringPiece* spki_out); 50 51} // namespace asn1 52 53} // namespace net 54 55#endif // NET_BASE_ASN1_UTIL_H_ 56