附　錄　E （規范性附錄） ASN.1模塊

E.1　形式定義

這個附錄定義了ASN.1模塊，其包括本部分規定的帶消息恢復的數字簽名的抽象語法。

MessageRecoverySignatureMechanisms {

iso(1) standard(0) signature-schemes(9796) part(3) asn1-module(1)

message-recovery-signature-mechanisms(0)

}

DEFINITIONS EXPLICIT TAGS ::= BEGIN

IMPORTS

HashFunctions

FROM DedicatedHashFunctions {

iso(1) standard(0) encryption-algorithms(10118) part(3) asn1-module(1)

dedicated-hash-functions(0) } ;

OID ::= OBJECT IDENTIFIER -- alias

SignatureWithMessageRecovery ::= SEQUENCE {

algorithm ALGORITHM.&id({MessageRecovery}),

parameters ALGORITHM.&Type({MessageRecovery}{@algorithm}) OPTIONAL

}

signatureMechanism OID ::= {

iso(1) standard(0) hash-functions(9796) part3(3) mechanism(0)

}

MessageRecovery ALGORITHM ::= {

dswmr-nr |

dswmr-ecmr |

dswmr-ecao |

dswmr-ecknr |

dswmr-ecpv |

dswmr-ecnr,

... -- Expect additional algorithms --

}

dswmr-nr ALGORITHM ::= {

OID nr PARMS HashFunctions

}

dswmr-ecmr ALGORITHM ::= {

OID ecmr PARMS HashFunctions

}

dswmr-ecao ALGORITHM ::= {

OID ecao PARMS HashFunctions

}

dswmr-ecknr ALGORITHM ::= {

OID ecknr PARMS HashFunctions

}

dswmr-ecpv ALGORITHM ::= {

OID ecpv PARMS HashFunctions

}

dswmr-ecnr ALGORITHM ::= {

OID ecnr PARMS HashFunctions

}

-- Cryptographic algorithm identification –

ALGORITHM ::= CLASS {

&id OBJECT IDENTIFIER UNIQUE,

&Type OPTIONAL

}

WITH SYNTAX { OID &id [PARMS &Type] }

-- Message recovery signature mechanisms --

nr OID ::= { signatureMechanism nr(0) }

ecmr OID ::= { signatureMechanism ecmr(1) }

ecao OID ::= { signatureMechanism ecao(2) }

ecknr OID ::= { signatureMechanism ecknr(3) }

ecpv OID ::= { signatureMechanism ecpv(4) }

ecnr OID ::= { signatureMechanism ecnr(5) }

END -- MessageRecoverySignatureMechanisms –

E.3　后續對象標識符的使用

任何一個簽名機制都使用雜湊函數。因此后續對象標識符可以遵循參考雜湊函數（例如，ISO/IEC 10118-3規定的專用的雜湊函數）。