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// Copyright 2015 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef BSSL_PKI_PARSE_CERTIFICATE_H_
#define BSSL_PKI_PARSE_CERTIFICATE_H_
#include <stdint.h>
#include <map>
#include <memory>
#include <optional>
#include <vector>
#include <openssl/base.h>
#include "general_names.h"
#include "input.h"
#include "parse_values.h"
namespace bssl {
namespace der {
class Parser;
}
class CertErrors;
struct ParsedTbsCertificate;
// Returns true if the given serial number (CertificateSerialNumber in RFC 5280)
// is valid:
//
// CertificateSerialNumber ::= INTEGER
//
// The input to this function is the (unverified) value octets of the INTEGER.
// This function will verify that:
//
// * The octets are a valid DER-encoding of an INTEGER (for instance, minimal
// encoding length).
//
// * No more than 20 octets are used.
//
// Note that it DOES NOT reject non-positive values (zero or negative).
//
// For reference, here is what RFC 5280 section 4.1.2.2 says:
//
// Given the uniqueness requirements above, serial numbers can be
// expected to contain long integers. Certificate users MUST be able to
// handle serialNumber values up to 20 octets. Conforming CAs MUST NOT
// use serialNumber values longer than 20 octets.
//
// Note: Non-conforming CAs may issue certificates with serial numbers
// that are negative or zero. Certificate users SHOULD be prepared to
// gracefully handle such certificates.
//
// |errors| must be a non-null destination for any errors/warnings. If
// |warnings_only| is set to true, then what would ordinarily be errors are
// instead added as warnings.
[[nodiscard]] OPENSSL_EXPORT bool VerifySerialNumber(const der::Input &value,
bool warnings_only,
CertErrors *errors);
// Consumes a "Time" value (as defined by RFC 5280) from |parser|. On success
// writes the result to |*out| and returns true. On failure no guarantees are
// made about the state of |parser|.
//
// From RFC 5280:
//
// Time ::= CHOICE {
// utcTime UTCTime,
// generalTime GeneralizedTime }
[[nodiscard]] OPENSSL_EXPORT bool ReadUTCOrGeneralizedTime(
der::Parser *parser, der::GeneralizedTime *out);
// Parses a DER-encoded "Validity" as specified by RFC 5280. Returns true on
// success and sets the results in |not_before| and |not_after|:
//
// Validity ::= SEQUENCE {
// notBefore Time,
// notAfter Time }
//
// Note that upon success it is NOT guaranteed that |*not_before <= *not_after|.
[[nodiscard]] OPENSSL_EXPORT bool ParseValidity(
const der::Input &validity_tlv, der::GeneralizedTime *not_before,
der::GeneralizedTime *not_after);
struct OPENSSL_EXPORT ParseCertificateOptions {
// If set to true, then parsing will skip checks on the certificate's serial
// number. The only requirement will be that the serial number is an INTEGER,
// however it is not required to be a valid DER-encoding (i.e. minimal
// encoding), nor is it required to be constrained to any particular length.
bool allow_invalid_serial_numbers = false;
};
// Parses a DER-encoded "Certificate" as specified by RFC 5280. Returns true on
// success and sets the results in the |out_*| parameters. On both the failure
// and success case, if |out_errors| was non-null it may contain extra error
// information.
//
// Note that on success the out parameters alias data from the input
// |certificate_tlv|. Hence the output values are only valid as long as
// |certificate_tlv| remains valid.
//
// On failure the out parameters have an undefined state, except for
// out_errors. Some of them may have been updated during parsing, whereas
// others may not have been changed.
//
// The out parameters represent each field of the Certificate SEQUENCE:
// Certificate ::= SEQUENCE {
//
// The |out_tbs_certificate_tlv| parameter corresponds with "tbsCertificate"
// from RFC 5280:
// tbsCertificate TBSCertificate,
//
// This contains the full (unverified) Tag-Length-Value for a SEQUENCE. No
// guarantees are made regarding the value of this SEQUENCE.
// This can be further parsed using ParseTbsCertificate().
//
// The |out_signature_algorithm_tlv| parameter corresponds with
// "signatureAlgorithm" from RFC 5280:
// signatureAlgorithm AlgorithmIdentifier,
//
// This contains the full (unverified) Tag-Length-Value for a SEQUENCE. No
// guarantees are made regarding the value of this SEQUENCE.
// This can be further parsed using SignatureValue::Create().
//
// The |out_signature_value| parameter corresponds with "signatureValue" from
// RFC 5280:
// signatureValue BIT STRING }
//
// Parsing guarantees that this is a valid BIT STRING.
[[nodiscard]] OPENSSL_EXPORT bool ParseCertificate(
const der::Input &certificate_tlv, der::Input *out_tbs_certificate_tlv,
der::Input *out_signature_algorithm_tlv,
der::BitString *out_signature_value, CertErrors *out_errors);
// Parses a DER-encoded "TBSCertificate" as specified by RFC 5280. Returns true
// on success and sets the results in |out|. Certain invalid inputs may
// be accepted based on the provided |options|.
//
// If |errors| was non-null then any warnings/errors that occur during parsing
// are added to it.
//
// Note that on success |out| aliases data from the input |tbs_tlv|.
// Hence the fields of the ParsedTbsCertificate are only valid as long as
// |tbs_tlv| remains valid.
//
// On failure |out| has an undefined state. Some of its fields may have been
// updated during parsing, whereas others may not have been changed.
//
// Refer to the per-field documentation of ParsedTbsCertificate for details on
// what validity checks parsing performs.
//
// TBSCertificate ::= SEQUENCE {
// version [0] EXPLICIT Version DEFAULT v1,
// serialNumber CertificateSerialNumber,
// signature AlgorithmIdentifier,
// issuer Name,
// validity Validity,
// subject Name,
// subjectPublicKeyInfo SubjectPublicKeyInfo,
// issuerUniqueID [1] IMPLICIT UniqueIdentifier OPTIONAL,
// -- If present, version MUST be v2 or v3
// subjectUniqueID [2] IMPLICIT UniqueIdentifier OPTIONAL,
// -- If present, version MUST be v2 or v3
// extensions [3] EXPLICIT Extensions OPTIONAL
// -- If present, version MUST be v3
// }
[[nodiscard]] OPENSSL_EXPORT bool ParseTbsCertificate(
const der::Input &tbs_tlv, const ParseCertificateOptions &options,
ParsedTbsCertificate *out, CertErrors *errors);
// Represents a "Version" from RFC 5280:
// Version ::= INTEGER { v1(0), v2(1), v3(2) }
enum class CertificateVersion {
V1,
V2,
V3,
};
// ParsedTbsCertificate contains pointers to the main fields of a DER-encoded
// RFC 5280 "TBSCertificate".
//
// ParsedTbsCertificate is expected to be filled by ParseTbsCertificate(), so
// subsequent field descriptions are in terms of what ParseTbsCertificate()
// sets.
struct OPENSSL_EXPORT ParsedTbsCertificate {
ParsedTbsCertificate();
ParsedTbsCertificate(ParsedTbsCertificate &&other);
ParsedTbsCertificate &operator=(ParsedTbsCertificate &&other) = default;
~ParsedTbsCertificate();
// Corresponds with "version" from RFC 5280:
// version [0] EXPLICIT Version DEFAULT v1,
//
// Parsing guarantees that the version is one of v1, v2, or v3.
CertificateVersion version = CertificateVersion::V1;
// Corresponds with "serialNumber" from RFC 5280:
// serialNumber CertificateSerialNumber,
//
// This field specifically contains the content bytes of the INTEGER. So for
// instance if the serial number was 1000 then this would contain bytes
// {0x03, 0xE8}.
//
// The serial number may or may not be a valid DER-encoded INTEGER:
//
// If the option |allow_invalid_serial_numbers=true| was used during
// parsing, then nothing further can be assumed about these bytes.
//
// Otherwise if |allow_invalid_serial_numbers=false| then in addition
// to being a valid DER-encoded INTEGER, parsing guarantees that
// the serial number is at most 20 bytes long. Parsing does NOT guarantee
// that the integer is positive (might be zero or negative).
der::Input serial_number;
// Corresponds with "signatureAlgorithm" from RFC 5280:
// signatureAlgorithm AlgorithmIdentifier,
//
// This contains the full (unverified) Tag-Length-Value for a SEQUENCE. No
// guarantees are made regarding the value of this SEQUENCE.
//
// This can be further parsed using SignatureValue::Create().
der::Input signature_algorithm_tlv;
// Corresponds with "issuer" from RFC 5280:
// issuer Name,
//
// This contains the full (unverified) Tag-Length-Value for a SEQUENCE. No
// guarantees are made regarding the value of this SEQUENCE.
der::Input issuer_tlv;
// Corresponds with "validity" from RFC 5280:
// validity Validity,
//
// Where Validity is defined as:
//
// Validity ::= SEQUENCE {
// notBefore Time,
// notAfter Time }
//
// Parsing guarantees that notBefore (validity_not_before) and notAfter
// (validity_not_after) are valid DER-encoded dates, however it DOES NOT
// gurantee anything about their values. For instance notAfter could be
// before notBefore, or the dates could indicate an expired certificate.
// Consumers are responsible for testing expiration.
der::GeneralizedTime validity_not_before;
der::GeneralizedTime validity_not_after;
// Corresponds with "subject" from RFC 5280:
// subject Name,
//
// This contains the full (unverified) Tag-Length-Value for a SEQUENCE. No
// guarantees are made regarding the value of this SEQUENCE.
der::Input subject_tlv;
// Corresponds with "subjectPublicKeyInfo" from RFC 5280:
// subjectPublicKeyInfo SubjectPublicKeyInfo,
//
// This contains the full (unverified) Tag-Length-Value for a SEQUENCE. No
// guarantees are made regarding the value of this SEQUENCE.
der::Input spki_tlv;
// Corresponds with "issuerUniqueID" from RFC 5280:
// issuerUniqueID [1] IMPLICIT UniqueIdentifier OPTIONAL,
// -- If present, version MUST be v2 or v3
//
// Parsing guarantees that if issuer_unique_id is present it is a valid BIT
// STRING, and that the version is either v2 or v3
std::optional<der::BitString> issuer_unique_id;
// Corresponds with "subjectUniqueID" from RFC 5280:
// subjectUniqueID [2] IMPLICIT UniqueIdentifier OPTIONAL,
// -- If present, version MUST be v2 or v3
//
// Parsing guarantees that if subject_unique_id is present it is a valid BIT
// STRING, and that the version is either v2 or v3
std::optional<der::BitString> subject_unique_id;
// Corresponds with "extensions" from RFC 5280:
// extensions [3] EXPLICIT Extensions OPTIONAL
// -- If present, version MUST be v3
//
//
// This contains the full (unverified) Tag-Length-Value for a SEQUENCE. No
// guarantees are made regarding the value of this SEQUENCE. (Note that the
// EXPLICIT outer tag is stripped.)
//
// Parsing guarantees that if extensions is present the version is v3.
std::optional<der::Input> extensions_tlv;
};
// ParsedExtension represents a parsed "Extension" from RFC 5280. It contains
// der:Inputs which are not owned so the associated data must be kept alive.
//
// Extension ::= SEQUENCE {
// extnID OBJECT IDENTIFIER,
// critical BOOLEAN DEFAULT FALSE,
// extnValue OCTET STRING
// -- contains the DER encoding of an ASN.1 value
// -- corresponding to the extension type identified
// -- by extnID
// }
struct OPENSSL_EXPORT ParsedExtension {
der::Input oid;
// |value| will contain the contents of the OCTET STRING. For instance for
// basicConstraints it will be the TLV for a SEQUENCE.
der::Input value;
bool critical = false;
};
// Parses a DER-encoded "Extension" as specified by RFC 5280. Returns true on
// success and sets the results in |out|.
//
// Note that on success |out| aliases data from the input |extension_tlv|.
// Hence the fields of the ParsedExtension are only valid as long as
// |extension_tlv| remains valid.
//
// On failure |out| has an undefined state. Some of its fields may have been
// updated during parsing, whereas others may not have been changed.
[[nodiscard]] OPENSSL_EXPORT bool ParseExtension(
const der::Input &extension_tlv, ParsedExtension *out);
// From RFC 5280:
//
// id-ce-subjectKeyIdentifier OBJECT IDENTIFIER ::= { id-ce 14 }
//
// In dotted notation: 2.5.29.14
inline constexpr uint8_t kSubjectKeyIdentifierOid[] = {0x55, 0x1d, 0x0e};
// From RFC 5280:
//
// id-ce-keyUsage OBJECT IDENTIFIER ::= { id-ce 15 }
//
// In dotted notation: 2.5.29.15
inline constexpr uint8_t kKeyUsageOid[] = {0x55, 0x1d, 0x0f};
// From RFC 5280:
//
// id-ce-subjectAltName OBJECT IDENTIFIER ::= { id-ce 17 }
//
// In dotted notation: 2.5.29.17
inline constexpr uint8_t kSubjectAltNameOid[] = {0x55, 0x1d, 0x11};
// From RFC 5280:
//
// id-ce-basicConstraints OBJECT IDENTIFIER ::= { id-ce 19 }
//
// In dotted notation: 2.5.29.19
inline constexpr uint8_t kBasicConstraintsOid[] = {0x55, 0x1d, 0x13};
// From RFC 5280:
//
// id-ce-nameConstraints OBJECT IDENTIFIER ::= { id-ce 30 }
//
// In dotted notation: 2.5.29.30
inline constexpr uint8_t kNameConstraintsOid[] = {0x55, 0x1d, 0x1e};
// From RFC 5280:
//
// id-ce-certificatePolicies OBJECT IDENTIFIER ::= { id-ce 32 }
//
// In dotted notation: 2.5.29.32
inline constexpr uint8_t kCertificatePoliciesOid[] = {0x55, 0x1d, 0x20};
// From RFC 5280:
//
// id-ce-authorityKeyIdentifier OBJECT IDENTIFIER ::= { id-ce 35 }
//
// In dotted notation: 2.5.29.35
inline constexpr uint8_t kAuthorityKeyIdentifierOid[] = {0x55, 0x1d, 0x23};
// From RFC 5280:
//
// id-ce-policyConstraints OBJECT IDENTIFIER ::= { id-ce 36 }
//
// In dotted notation: 2.5.29.36
inline constexpr uint8_t kPolicyConstraintsOid[] = {0x55, 0x1d, 0x24};
// From RFC 5280:
//
// id-ce-extKeyUsage OBJECT IDENTIFIER ::= { id-ce 37 }
//
// In dotted notation: 2.5.29.37
inline constexpr uint8_t kExtKeyUsageOid[] = {0x55, 0x1d, 0x25};
// From RFC 5280:
//
// id-pe-authorityInfoAccess OBJECT IDENTIFIER ::= { id-pe 1 }
//
// In dotted notation: 1.3.6.1.5.5.7.1.1
inline constexpr uint8_t kAuthorityInfoAccessOid[] = {0x2B, 0x06, 0x01, 0x05,
0x05, 0x07, 0x01, 0x01};
// From RFC 5280:
//
// id-ad-caIssuers OBJECT IDENTIFIER ::= { id-ad 2 }
//
// In dotted notation: 1.3.6.1.5.5.7.48.2
inline constexpr uint8_t kAdCaIssuersOid[] = {0x2B, 0x06, 0x01, 0x05,
0x05, 0x07, 0x30, 0x02};
// From RFC 5280:
//
// id-ad-ocsp OBJECT IDENTIFIER ::= { id-ad 1 }
//
// In dotted notation: 1.3.6.1.5.5.7.48.1
inline constexpr uint8_t kAdOcspOid[] = {0x2B, 0x06, 0x01, 0x05,
0x05, 0x07, 0x30, 0x01};
// From RFC 5280:
//
// id-ce-cRLDistributionPoints OBJECT IDENTIFIER ::= { id-ce 31 }
//
// In dotted notation: 2.5.29.31
inline constexpr uint8_t kCrlDistributionPointsOid[] = {0x55, 0x1d, 0x1f};
// From
// https://learn.microsoft.com/en-us/windows/win32/seccertenroll/supported-extensions#msapplicationpolicies
//
// OID: XCN_OID_APPLICATION_CERT_POLICIES (1.3.6.1.4.1.311.21.10)
inline constexpr uint8_t kMSApplicationPoliciesOid[] = {
0x2b, 0x06, 0x01, 0x04, 0x01, 0x82, 0x37, 0x15, 0x0a};
// Parses the Extensions sequence as defined by RFC 5280. Extensions are added
// to the map |extensions| keyed by the OID. Parsing guarantees that each OID
// is unique. Note that certificate verification must consume each extension
// marked as critical.
//
// Returns true on success and fills |extensions|. The output will reference
// bytes in |extensions_tlv|, so that data must be kept alive.
// On failure |extensions| may be partially written to and should not be used.
[[nodiscard]] OPENSSL_EXPORT bool ParseExtensions(
const der::Input &extensions_tlv,
std::map<der::Input, ParsedExtension> *extensions);
// Removes the extension with OID |oid| from |unconsumed_extensions| and fills
// |extension| with the matching extension value. If there was no extension
// matching |oid| then returns |false|.
[[nodiscard]] OPENSSL_EXPORT bool ConsumeExtension(
const der::Input &oid,
std::map<der::Input, ParsedExtension> *unconsumed_extensions,
ParsedExtension *extension);
struct ParsedBasicConstraints {
bool is_ca = false;
bool has_path_len = false;
uint8_t path_len = 0;
};
// Parses the BasicConstraints extension as defined by RFC 5280:
//
// BasicConstraints ::= SEQUENCE {
// cA BOOLEAN DEFAULT FALSE,
// pathLenConstraint INTEGER (0..MAX) OPTIONAL }
//
// The maximum allowed value of pathLenConstraints will be whatever can fit
// into a uint8_t.
[[nodiscard]] OPENSSL_EXPORT bool ParseBasicConstraints(
const der::Input &basic_constraints_tlv, ParsedBasicConstraints *out);
// KeyUsageBit contains the index for a particular key usage. The index is
// measured from the most significant bit of a bit string.
//
// From RFC 5280 section 4.2.1.3:
//
// KeyUsage ::= BIT STRING {
// digitalSignature (0),
// nonRepudiation (1), -- recent editions of X.509 have
// -- renamed this bit to contentCommitment
// keyEncipherment (2),
// dataEncipherment (3),
// keyAgreement (4),
// keyCertSign (5),
// cRLSign (6),
// encipherOnly (7),
// decipherOnly (8) }
enum KeyUsageBit {
KEY_USAGE_BIT_DIGITAL_SIGNATURE = 0,
KEY_USAGE_BIT_NON_REPUDIATION = 1,
KEY_USAGE_BIT_KEY_ENCIPHERMENT = 2,
KEY_USAGE_BIT_DATA_ENCIPHERMENT = 3,
KEY_USAGE_BIT_KEY_AGREEMENT = 4,
KEY_USAGE_BIT_KEY_CERT_SIGN = 5,
KEY_USAGE_BIT_CRL_SIGN = 6,
KEY_USAGE_BIT_ENCIPHER_ONLY = 7,
KEY_USAGE_BIT_DECIPHER_ONLY = 8,
};
// Parses the KeyUsage extension as defined by RFC 5280. Returns true on
// success, and |key_usage| will alias data in |key_usage_tlv|. On failure
// returns false, and |key_usage| may have been modified.
//
// In addition to validating that key_usage_tlv is a BIT STRING, this does
// additional KeyUsage specific validations such as requiring at least 1 bit to
// be set.
//
// To test if a particular key usage is set, call, e.g.:
// key_usage->AssertsBit(KEY_USAGE_BIT_DIGITAL_SIGNATURE);
[[nodiscard]] OPENSSL_EXPORT bool ParseKeyUsage(const der::Input &key_usage_tlv,
der::BitString *key_usage);
struct AuthorityInfoAccessDescription {
// The accessMethod DER OID value.
der::Input access_method_oid;
// The accessLocation DER TLV.
der::Input access_location;
};
// Parses the Authority Information Access extension defined by RFC 5280.
// Returns true on success, and |out_access_descriptions| will alias data
// in |authority_info_access_tlv|.On failure returns false, and
// out_access_descriptions may have been partially filled.
//
// No validation is performed on the contents of the
// AuthorityInfoAccessDescription fields.
[[nodiscard]] OPENSSL_EXPORT bool ParseAuthorityInfoAccess(
const der::Input &authority_info_access_tlv,
std::vector<AuthorityInfoAccessDescription> *out_access_descriptions);
// Parses the Authority Information Access extension defined by RFC 5280,
// extracting the caIssuers URIs and OCSP URIs.
//
// Returns true on success, and |out_ca_issuers_uris| and |out_ocsp_uris| will
// alias data in |authority_info_access_tlv|. On failure returns false, and
// |out_ca_issuers_uris| and |out_ocsp_uris| may have been partially filled.
//
// |out_ca_issuers_uris| is filled with the accessLocations of type
// uniformResourceIdentifier for the accessMethod id-ad-caIssuers.
// |out_ocsp_uris| is filled with the accessLocations of type
// uniformResourceIdentifier for the accessMethod id-ad-ocsp.
//
// The values in |out_ca_issuers_uris| and |out_ocsp_uris| are checked to be
// IA5String (ASCII strings), but no other validation is performed on them.
//
// accessMethods other than id-ad-caIssuers and id-ad-ocsp are silently ignored.
// accessLocation types other than uniformResourceIdentifier are silently
// ignored.
[[nodiscard]] OPENSSL_EXPORT bool ParseAuthorityInfoAccessURIs(
const der::Input &authority_info_access_tlv,
std::vector<std::string_view> *out_ca_issuers_uris,
std::vector<std::string_view> *out_ocsp_uris);
// ParsedDistributionPoint represents a parsed DistributionPoint from RFC 5280.
//
// DistributionPoint ::= SEQUENCE {
// distributionPoint [0] DistributionPointName OPTIONAL,
// reasons [1] ReasonFlags OPTIONAL,
// cRLIssuer [2] GeneralNames OPTIONAL }
struct OPENSSL_EXPORT ParsedDistributionPoint {
ParsedDistributionPoint();
ParsedDistributionPoint(ParsedDistributionPoint &&other);
~ParsedDistributionPoint();
// The parsed fullName, if distributionPoint was present and was a fullName.
std::unique_ptr<GeneralNames> distribution_point_fullname;
// If present, the DER encoded value of the nameRelativeToCRLIssuer field.
// This should be a RelativeDistinguishedName, but the parser does not
// validate it.
std::optional<der::Input> distribution_point_name_relative_to_crl_issuer;
// If present, the DER encoded value of the reasons field. This should be a
// ReasonFlags bitString, but the parser does not validate it.
std::optional<der::Input> reasons;
// If present, the DER encoded value of the cRLIssuer field. This should be a
// GeneralNames, but the parser does not validate it.
std::optional<der::Input> crl_issuer;
};
// Parses the value of a CRL Distribution Points extension (sequence of
// DistributionPoint). Return true on success, and fills |distribution_points|
// with values that reference data in |distribution_points_tlv|.
[[nodiscard]] OPENSSL_EXPORT bool ParseCrlDistributionPoints(
const der::Input &distribution_points_tlv,
std::vector<ParsedDistributionPoint> *distribution_points);
// Represents the AuthorityKeyIdentifier extension defined by RFC 5280 section
// 4.2.1.1.
//
// AuthorityKeyIdentifier ::= SEQUENCE {
// keyIdentifier [0] KeyIdentifier OPTIONAL,
// authorityCertIssuer [1] GeneralNames OPTIONAL,
// authorityCertSerialNumber [2] CertificateSerialNumber OPTIONAL }
//
// KeyIdentifier ::= OCTET STRING
struct OPENSSL_EXPORT ParsedAuthorityKeyIdentifier {
ParsedAuthorityKeyIdentifier();
~ParsedAuthorityKeyIdentifier();
ParsedAuthorityKeyIdentifier(ParsedAuthorityKeyIdentifier &&other);
ParsedAuthorityKeyIdentifier &operator=(ParsedAuthorityKeyIdentifier &&other);
// The keyIdentifier, which is an OCTET STRING.
std::optional<der::Input> key_identifier;
// The authorityCertIssuer, which should be a GeneralNames, but this is not
// enforced by ParseAuthorityKeyIdentifier.
std::optional<der::Input> authority_cert_issuer;
// The DER authorityCertSerialNumber, which should be a
// CertificateSerialNumber (an INTEGER) but this is not enforced by
// ParseAuthorityKeyIdentifier.
std::optional<der::Input> authority_cert_serial_number;
};
// Parses the value of an authorityKeyIdentifier extension. Returns true on
// success and fills |authority_key_identifier| with values that reference data
// in |extension_value|. On failure the state of |authority_key_identifier| is
// not guaranteed.
[[nodiscard]] OPENSSL_EXPORT bool ParseAuthorityKeyIdentifier(
const der::Input &extension_value,
ParsedAuthorityKeyIdentifier *authority_key_identifier);
// Parses the value of a subjectKeyIdentifier extension. Returns true on
// success and |subject_key_identifier| references data in |extension_value|.
// On failure the state of |subject_key_identifier| is not guaranteed.
[[nodiscard]] OPENSSL_EXPORT bool ParseSubjectKeyIdentifier(
const der::Input &extension_value, der::Input *subject_key_identifier);
} // namespace bssl
#endif // BSSL_PKI_PARSE_CERTIFICATE_H_