2 Public-Key Records

This chapter briefly describes Erlang records derived from ASN.1 specifications used to handle public key infrastructure. The scope is to describe the data types of each component, not the semantics. For information on the semantics, refer to the relevant standards and RFCs linked in the sections below.

Use the following include directive to get access to the records and constant macros described in the following sections:

-include_lib("public_key/include/public_key.hrl"). 

2.1 Data Types

Common non-standard Erlang data types used to describe the record fields in the following sections and which are not defined in the Public Key Reference Manual follows here:

time() =

utc_time() | general_time()

utc_time() =

{utcTime, "YYMMDDHHMMSSZ"}

general_time() =

{generalTime, "YYYYMMDDHHMMSSZ"}

general_name() =

{rfc822Name, string()}

| {dNSName, string()}

| {x400Address, string()}

| {directoryName, {rdnSequence, [#AttributeTypeAndValue'{}]}}

| {ediPartyName, special_string()}

| {ediPartyName, special_string(), special_string()}

| {uniformResourceIdentifier, string()}

| {iPAddress, string()}

| {registeredId, oid()}

| {otherName, term()}

special_string() =

{teletexString, string()}

| {printableString, string()}

| {universalString, string()}

| {utf8String, binary()}

| {bmpString, string()}

dist_reason() =

unused

| keyCompromise

| cACompromise

| affiliationChanged

| superseded

| cessationOfOperation

| certificateHold

| privilegeWithdrawn

| aACompromise

OID_macro() =

?OID_name()

OID_name() =

atom()

2.2 rsa

Erlang representation of Rivest-Shamir-Adleman cryptosystem (RSA) keys follows:

#'RSAPublicKey'{
	  modulus,       % integer()
	  publicExponent % integer()
	  }.

#'RSAPrivateKey'{
          version,         % two-prime | multi
	  modulus,         % integer()
	  publicExponent,  % integer()
	  privateExponent, % integer()
	  prime1,          % integer() 
	  prime2,          % integer()
	  exponent1,       % integer()
	  exponent2,       % integer()
	  coefficient,     % integer()
	  otherPrimeInfos  % [#OtherPrimeInfo{}] | asn1_NOVALUE
	 }.

#'OtherPrimeInfo'{
	prime,           % integer()
	exponent,        % integer()
	coefficient      % integer()
 	}.

#'RSASSA-PSS-params'{hashAlgorithm,     % #'HashAlgorithm'{}},  
	             maskGenAlgorithm,  % #'MaskGenAlgorithm'{}},
		     saltLength,        % integer(),
		     trailerField,      % integer()
		     }.
		     
#'HashAlgorithm'{algorithm,  % oid()
                 parameters  % defaults to asn1_NOVALUE
                 }.
		 
#'MaskGenAlgorithm'{algorithm,  % oid()
                    parameters, % defaults to asn1_NOVALUE
                   }.

2.3 dsa

Erlang representation of Digital Signature Algorithm (DSA) keys

#'DSAPrivateKey',{
	  version,      % integer()
	  p,            % integer()
	  q,            % integer()
	  g,            % integer()
	  y,            % integer()
	  x             % integer()
	  }.

#'Dss-Parms',{
         p,         % integer()
	 q,         % integer()
	 g          % integer()
	 }. 

2.4 ECDSA and EDDSA

Erlang representation of Elliptic Curve Digital Signature Algorithm (ECDSA) and Edwards-Curve Digital Signature Algorithm (EDDSA) where parameters in the private key will be {namedCurve, ?'id-Ed25519' | ?'id-Ed448'}.

#'ECPrivateKey'{
          version,       % integer()
	  privateKey,    % binary()  
          parameters,    % {ecParameters, #'ECParameters'{}} |
                         % {namedCurve, Oid::tuple()} |
                         % {implicitlyCA, 'NULL'}
	  publicKey      % bitstring()
	  }.
	  
#'ECParameters'{
      version,    % integer()
      fieldID,    % #'FieldID'{}
      curve,      % #'Curve'{}
      base,       % binary()       
      order,      % integer()        
      cofactor    % integer()
      }.
      
#'Curve'{
	a,        % binary()
	b,        % binary() 
	seed      % bitstring() - optional

	}.

#'FieldID'{
	fieldType,    % oid()
	parameters    % Depending on fieldType
	}.

#'ECPoint'{
      point %  binary() - the public key
      }.

2.5 PKIX Certificates

Erlang representation of PKIX certificates derived from ASN.1 specifications see also X509 certificates (RFC 5280), also referred to as plain type, are as follows:

#'Certificate'{
		tbsCertificate,        % #'TBSCertificate'{}
		signatureAlgorithm,    % #'AlgorithmIdentifier'{} 
		signature              % bitstring()
	       }.

#'TBSCertificate'{
	  version,              % v1 | v2 | v3 
	  serialNumber,         % integer() 
	  signature,            % #'AlgorithmIdentifier'{} 
	  issuer,               % {rdnSequence, [#AttributeTypeAndValue'{}]} 
	  validity,             % #'Validity'{}
	  subject,              % {rdnSequence, [#AttributeTypeAndValue'{}]} 
	  subjectPublicKeyInfo, % #'SubjectPublicKeyInfo'{}
	  issuerUniqueID,       % binary() | asn1_novalue
	  subjectUniqueID,      % binary() | asn1_novalue
	  extensions            % [#'Extension'{}] 
	 }.
	  
#'AlgorithmIdentifier'{
	  algorithm,  % oid() 
	  parameters  % der_encoded()
	 }.

Erlang alternate representation of PKIX certificate, also referred to as otp type

#'OTPCertificate'{
		tbsCertificate,        % #'OTPTBSCertificate'{}
		signatureAlgorithm,    % #'SignatureAlgorithm'
		signature              % bitstring()
	       }.

#'OTPTBSCertificate'{
	  version,              % v1 | v2 | v3 
	  serialNumber,         % integer() 
	  signature,            % #'SignatureAlgorithm'
	  issuer,               % {rdnSequence, [#AttributeTypeAndValue'{}]} 
	  validity,             % #'Validity'{}
	  subject,              % {rdnSequence, [#AttributeTypeAndValue'{}]} 
	  subjectPublicKeyInfo, % #'OTPSubjectPublicKeyInfo'{}
	  issuerUniqueID,       % binary() | asn1_novalue
	  subjectUniqueID,      % binary() | asn1_novalue
	  extensions            % [#'Extension'{}] 
	 }.
	  
#'SignatureAlgorithm'{
	  algorithm,  % id_signature_algorithm()
	  parameters  % asn1_novalue | #'Dss-Parms'{}
	 }.

id_signature_algorithm() = OID_macro()

The available OID names are as follows:

The data type 'AttributeTypeAndValue', is represented as the following erlang record:

#'AttributeTypeAndValue'{
	  type,   % id_attributes()
	  value   % term() 
	 }.

The attribute OID name atoms and their corresponding value types are as follows:

The data types 'Validity', 'SubjectPublicKeyInfo', and 'SubjectPublicKeyInfoAlgorithm' are represented as the following Erlang records:

#'Validity'{ 
	  notBefore, % time()
	  notAfter   % time()
	 }.
	 
#'SubjectPublicKeyInfo'{
	  algorithm,       % #AlgorithmIdentifier{} 
	  subjectPublicKey % binary() 
	 }.

#'SubjectPublicKeyInfoAlgorithm'{
	  algorithm,  % id_public_key_algorithm()
	  parameters  % public_key_params()
	 }.

The public-key algorithm OID name atoms are as follows:

#'Extension'{
	  extnID,    % id_extensions() | oid() 
	  critical,  % boolean()
	  extnValue  % der_encoded()
	 }.

id_extensions() Standard Certificate Extensions, Private Internet Extensions, CRL Extensions and CRL Entry Extensions.

2.6 Standard Certificate Extensions

The standard certificate extensions OID name atoms and their corresponding value types are as follows:

Here:

key_usage()

=

digitalSignature

| nonRepudiation

| keyEncipherment

| dataEncipherment

| keyAgreement

| keyCertSign

| cRLSign

| encipherOnly

| decipherOnly

And for id_key_purpose():

#'AuthorityKeyIdentifier'{
	  keyIdentifier,	    % oid()
	  authorityCertIssuer,      % general_name()
	  authorityCertSerialNumber % integer() 
	 }.

#'PrivateKeyUsagePeriod'{
	  notBefore,   % general_time()
	  notAfter     % general_time()
	 }.

#'PolicyInformation'{
	  policyIdentifier,  % oid()
	  policyQualifiers   % [#PolicyQualifierInfo{}]
	 }.

#'PolicyQualifierInfo'{
	  policyQualifierId,   % oid()
	  qualifier            % string() | #'UserNotice'{}
	 }.

#'UserNotice'{
         noticeRef,   % #'NoticeReference'{}
	 explicitText % string()
	 }.

#'NoticeReference'{
         organization,    % string()
	 noticeNumbers    % [integer()]
	 }.

#'PolicyMappings_SEQOF'{
	  issuerDomainPolicy,  % oid()
	  subjectDomainPolicy  % oid()
	 }.

#'Attribute'{
          type,  % oid()
	  values % [der_encoded()]
	  }).

#'BasicConstraints'{
	  cA,		    % boolean()
	  pathLenConstraint % integer()
	 }).

#'NameConstraints'{
	  permittedSubtrees, % [#'GeneralSubtree'{}]
	  excludedSubtrees   % [#'GeneralSubtree'{}]
	 }).

#'GeneralSubtree'{
	  base,    % general_name()
	  minimum, % integer()
	  maximum  % integer()
	 }).

#'PolicyConstraints'{
	  requireExplicitPolicy, % integer()
	  inhibitPolicyMapping   % integer()
	 }).

#'DistributionPoint'{
	  distributionPoint, % {fullName, [general_name()]} | {nameRelativeToCRLIssuer,
	  [#AttributeTypeAndValue{}]}
	  reasons,           % [dist_reason()]
	  cRLIssuer          % [general_name()]
	 }).

2.7 Private Internet Extensions

The private internet extensions OID name atoms and their corresponding value types are as follows:

#'AccessDescription'{
           accessMethod,    % oid()
	   accessLocation   % general_name()
	 }).

2.8 CRL and CRL Extensions Profile

Erlang representation of CRL and CRL extensions profile derived from ASN.1 specifications and RFC 5280 are as follows:

#'CertificateList'{
          tbsCertList,        % #'TBSCertList{}
          signatureAlgorithm, % #'AlgorithmIdentifier'{} 
          signature           % bitstring()
	  }).

#'TBSCertList'{
      version,             % v2 (if defined)
      signature,           % #AlgorithmIdentifier{}
      issuer,              % {rdnSequence, [#AttributeTypeAndValue'{}]} 
      thisUpdate,          % time()
      nextUpdate,          % time() 
      revokedCertificates, % [#'TBSCertList_revokedCertificates_SEQOF'{}]
      crlExtensions        % [#'Extension'{}]
      }).

#'TBSCertList_revokedCertificates_SEQOF'{
         userCertificate,      % integer()
 	 revocationDate,       % timer()
	 crlEntryExtensions    % [#'Extension'{}]
	 }).

CRL Extensions

The CRL extensions OID name atoms and their corresponding value types are as follows:

Here, the data type 'IssuingDistributionPoint' is represented as the following Erlang record:

#'IssuingDistributionPoint'{
          distributionPoint,         % {fullName, [general_name()]} | {nameRelativeToCRLIssuer,
	  [#AttributeTypeAndValue'{}]}
	  onlyContainsUserCerts,     % boolean()
	  onlyContainsCACerts,       % boolean()
	  onlySomeReasons,           % [dist_reason()]
	  indirectCRL,               % boolean()
	  onlyContainsAttributeCerts % boolean()
	  }).

CRL Entry Extensions

The CRL entry extensions OID name atoms and their corresponding value types are as follows:

Here:

crl_reason()

=

unspecified

| keyCompromise

| cACompromise

| affiliationChanged

| superseded

| cessationOfOperation

| certificateHold

| removeFromCRL

| privilegeWithdrawn

| aACompromise

PKCS#10 Certification Request

Erlang representation of a PKCS#10 certification request derived from ASN.1 specifications and RFC 5280 are as follows:

#'CertificationRequest'{
          certificationRequestInfo #'CertificationRequestInfo'{},
	  signatureAlgorithm	   #'CertificationRequest_signatureAlgorithm'{}}.
	  signature                bitstring()
	  }

#'CertificationRequestInfo'{
	  version       atom(),
	  subject       {rdnSequence, [#AttributeTypeAndValue'{}]} ,
	  subjectPKInfo #'CertificationRequestInfo_subjectPKInfo'{},
	  attributes    [#'AttributePKCS-10' {}]
	  }

#'CertificationRequestInfo_subjectPKInfo'{
          algorithm		#'CertificationRequestInfo_subjectPKInfo_algorithm'{}
	  subjectPublicKey 	  bitstring()
	  }

#'CertificationRequestInfo_subjectPKInfo_algorithm'{
     algorithm = oid(),
     parameters = der_encoded()
}	  

#'CertificationRequest_signatureAlgorithm'{
     algorithm = oid(),
     parameters = der_encoded()
     }

#'AttributePKCS-10'{
    type = oid(),
    values = [der_encoded()]
}