net: extract net/cert out of net/base

net/base/asn1_util.h

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef NET_BASE_ASN1_UTIL_H_
-#define NET_BASE_ASN1_UTIL_H_
-
-#include <vector>
-
-#include "base/string_piece.h"
-#include "net/base/net_export.h"
-
-namespace net {
-
-namespace asn1 {
-
-// These are the DER encodings of the tag byte for ASN.1 objects.
-static const unsigned kBOOLEAN = 0x01;
-static const unsigned kINTEGER = 0x02;
-static const unsigned kBITSTRING = 0x03;
-static const unsigned kOCTETSTRING = 0x04;
-static const unsigned kOID = 0x06;
-static const unsigned kSEQUENCE = 0x30;
-
-// These are flags that can be ORed with the above tag numbers.
-static const unsigned kContextSpecific = 0x80;
-static const unsigned kConstructed = 0x20;
-
-// kAny matches any tag value;
-static const unsigned kAny = 0x10000;
-// kOptional denotes an optional element.
-static const unsigned kOptional = 0x20000;
-
-// ParseElement parses a DER encoded ASN1 element from |in|, requiring that
-// it have the given |tag_value|. It returns true on success. The following
-// limitations are imposed:
-//   1) tag numbers > 31 are not permitted.
-//   2) lengths > 65535 are not permitted.
-// On successful return:
-//   |in| is advanced over the element
-//   |out| contains the element, including the tag and length bytes.
-//   |out_header_len| contains the length of the tag and length bytes in |out|.
-//
-// If |tag_value & kOptional| is true then *out_header_len can be zero after a
-// true return value if the element was not found.
-bool ParseElement(base::StringPiece* in,
-                  unsigned tag_value,
-                  base::StringPiece* out,
-                  unsigned *out_header_len);
-
-// GetElement performs the same actions as ParseElement, except that the header
-// bytes are not included in the output.
-//
-// If |tag_value & kOptional| is true then this function cannot distinguish
-// between a missing optional element and an empty one.
-bool GetElement(base::StringPiece* in,
-                unsigned tag_value,
-                base::StringPiece* out);
-
-// ExtractSPKIFromDERCert parses the DER encoded certificate in |cert| and
-// extracts the bytes of the SubjectPublicKeyInfo. On successful return,
-// |spki_out| is set to contain the SPKI, pointing into |cert|.
-NET_EXPORT_PRIVATE bool ExtractSPKIFromDERCert(base::StringPiece cert,
-                                               base::StringPiece* spki_out);
-
-// ExtractSubjectPublicKeyFromSPKI parses the DER encoded SubjectPublicKeyInfo
-// in |spki| and extracts the bytes of the SubjectPublicKey. On successful
-// return, |spk_out| is set to contain the public key, pointing into |spki|.
-NET_EXPORT_PRIVATE bool ExtractSubjectPublicKeyFromSPKI(
-    base::StringPiece spki,
-    base::StringPiece* spk_out);
-
-// ExtractCRLURLsFromDERCert parses the DER encoded certificate in |cert| and
-// extracts the URL of each CRL. On successful return, the elements of
-// |urls_out| point into |cert|.
-//
-// CRLs that only cover a subset of the reasons are omitted as the spec
-// requires that at least one CRL be included that covers all reasons.
-//
-// CRLs that use an alternative issuer are also omitted.
-//
-// The nested set of GeneralNames is flattened into a single list because
-// having several CRLs with one location is equivalent to having one CRL with
-// several locations as far as a CRL filter is concerned.
-NET_EXPORT_PRIVATE bool ExtractCRLURLsFromDERCert(
-    base::StringPiece cert,
-    std::vector<base::StringPiece>* urls_out);
-
-} // namespace asn1
-
-} // namespace net
-
-#endif // NET_BASE_ASN1_UTIL_H_