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 11 namespace net { 12 13 namespace asn1 { 14 15 // These are the DER encodings of the tag byte for ASN.1 objects. 16 static const unsigned kINTEGER = 0x02; 17 static const unsigned kOID = 0x06; 18 static const unsigned kSEQUENCE = 0x30; 19 20 // These are flags that can be ORed with the above tag numbers. 21 static const unsigned kContextSpecific = 0x80; 22 static 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|. 33 bool 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. 40 bool 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|. 48 bool 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