rfc1781.txt

RFC 的详细文档！

   [8] L.L. Petersen. The profile naming service.  ACM Transactions on
       Computing Systems, 6(4):341--364, November 1988.

   [9] M.T. Rose. Realizing the White Pages using the OSI Directory
       Service. Technical Report 90--05--10--1, Performance Systems
       International, Inc., May 1990.




















Kille                                                          [Page 20]

RFC 1781                  User Friendly Naming                March 1995


12.  Security Considerations

   Security issues are not discussed in this memo.

13.  Author's Address

   Steve Kille
   ISODE Consortium
   The Dome
   The Square
   Richmond, Surrey
   TW9 1DT
   England

   Phone:[phone]
   EMail:  [e-mail]

   DN: CN=Steve Kille,
   O=ISODE Consortium, C=GB

   UFN: S. Kille,
   ISODE Consortium, GB





























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RFC 1781                  User Friendly Naming                March 1995


A.  Pseudo-code for the matching algorithm

   The following pseudo-code is intended to clarify the matching
   algorithm.  The language uses ASN.1 data types, with flow control
   "C"-like, but with keywords upper-cased.

PurportedName ::= SEQUENCE OF String
                -- simplication, as attribute types can optionally be
                -- specified

                -- Each element of the Purported Name is a string
                -- which has been parsed from the BNF

Attribute ::= SEQUENCE {
        type OBJECT IDENTIFIER,
        value ANY }

RDN ::= Attribute -- simplification, as can be multi-value

DN ::= SEQUENCE OF RDN

Environment ::= SEQUENCE OF DN

EnvironmentList ::= SEQUENCE OF SEQUENCE {
                        lower-bound INTEGER,
                        upper-bound INTEGER,
                        environment Environment }


friendlyMatch(p:  PurportedName; el:  EnvironmentList):    SET OF DN
{
                                -- Find correct environment

        IF length(el) == 0 THEN return(NULL);

        IF length(p) <= head(el).upper-bound
                        && length(p) >= head(el).lower-bound THEN
                return envMatch (p, head(el).environment);
        ELSE
                return(friendlyMatch(p, tail(el));
}

envMatch(p:  PurportedName; e:  Environment):    SET OF DN
{
                                -- Check elements of environment
                                -- in the defined order

        matches:  SET OF DN;



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RFC 1781                  User Friendly Naming                March 1995


        IF length(e) == 0 THEN return(NULL);

        matches = purportedMatch(head(e).DN, p)
        IF matches != NULL THEN
                return(matches);
        ELSE
                return(envMatch(p, tail(e));
}


purportedMatch(base:  DN; p:  PurportedName):  SET OF DN
{
        s:  String = head(p);
        matches:  SET OF DN = NULL;

        IF length(p) == 1 THEN
                IF length(base) == 0 THEN
                        IF (matches = rootSearch(s)) != NULL THEN
                                return(matches);
                        ELSE return(leafSearch(base, s, one-level);
                ELSE IF length(base) == 1 THEN
                        IF (matches = intSearch(base, s)) != NULL THEN
                                return(matches);
                        ELSE return(leafSearch(base, s, one-level);
                ELSE
                        IF (matches = leafSearch(base, s, subtree)) !=
                                NULL THEN return(matches);
                        ELSE return(intsearch(base, s);


        IF length(base) == 0 THEN
                FOR x IN rootSearch(s) DO
                        matches += (purportedMatch(x, tail(p));
        ELSE
                FOR x IN intSearch(base, s) DO
                        matches += (purportedMatch(x, tail(p));
        return(matches);
}













Kille                                                          [Page 23]

RFC 1781                  User Friendly Naming                March 1995


-- General.    Might need to tighten the filter for short strings,
-- in order to stop being flooded.    Alternatively, this could be
-- done if the loose search hits a size limit

rootSearch(s:  String):  SET OF DN
{
        IF length(s) == 2 THEN
                return(search(NULL, one-level, s, {CountryName,
                        FriendlyCountryName, OrganizationName},
                        {exact}, {Country, Organisation}));
                        -- test exact match only
                        -- probably a country code
        ELSE
                return(search(NULL, one-level, s, {OrganizationName,
                        FriendlyCountryName}, {substring, approx},
                        {Country, Organisation}));
}


intSearch( base:  DN; s:  String)
{
        IF present(base, OrgUnitName) THEN
                return(search(base, one-level, s, {OrgUnitName},
                        {substring, approx}, {OrgUnit}));
        ELSE IF present(base, OrganisationName) THEN
                return(search(base, one-level, s, {OrgUnitName,
                        LocalityName}, {substring, approx},
                        {Organization, OrgUnit, Locality}));
        ELSE IF present(base, LocalityName) THEN
                return(search(base, one-level, s, {OrganisationName},
                        {substring, approx}, {Locality});
        ELSE
                return(search(base, one-level, s, {OrganisationName,
                        LocalityName}, {substring, approx},
                        {Organisation, Locality}));
}


present(d:  DN; t:  AttributeType):  BOOLEAN
{
        FOR x IN d DO
                IF x.type == t THEN return(TRUE);
        return(FALSE);
}

SearchScope := ENUMERATED (base-object, one-level, subtree)

leafSearch(base:  DN; s:  String; search-scope:  SearchScope)



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RFC 1781                  User Friendly Naming                March 1995


{
        return(search(base, search-scope, s, {CommonName, Surname,
                UserId}, {substring, approx}));
}

search(base:  DN; search-scope:  SearchScope; s:  string;
        alist SET OF AttributeType; matchtypes SET OF MatchType
        objectClasses SET OF ObjectClass OPTIONAL): SET OF DN
{
        -- mapped onto Directory Search, with OR conjunction
        -- of filter items

        return dNSelect (s, search-results, alist);
}

read(base:  DN; alist SET OF AttributeType):  SET OF Attribute;
{
        -- mapped onto Directory Read
        -- Types repeated to deal with multiple values
        -- This would be implemented by returning selected info
        -- with the search operation
}

dNSelect(s:  String; dlist SET OF DN;
                     alist:  SET OF AttributeType):16SET0OF DN
{
        exact, good:  SET OF DN;

        FOR x IN dlist DO
                IF last(DN).Value == s THEN
                        exact += x;
                ELSE IF FOR y IN read(x, alist) DO
                        IF y.value == s THEN
                                good += x;

        IF exact != NULL THEN return(exact);
        IF good != NULL THEN return(good);
        return(userQuery(dlist));
}

userQuery(dlist SET OF DN): SET OF DN
{
        -- pass back up for manual checking
        -- user can strip all matches to force progres....
}

head()    -- return first element of list
tail()    -- return list with first element removed



Kille                                                          [Page 25]

RFC 1781                  User Friendly Naming                March 1995


length()  -- return size of list
last()    -- return last element of list

                    Figure 2: Matching Algorithm















































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