oracle PL/SQL 如何计算 IPv6 cidr 的范围 ip

Question

带有 CIDR 的 ex.IPv6 地址:2620:0:2d0:200::7/32输出起始范围:2620:0:0:0:0:0:0:0结束范围:2620:0:ffff:ffff:ffff:ffff:ffff:ffff

如何用PL/SQL计算？

Answer 1

有一次我写了一个通用的 PL/SQL 包，您可以在其中进行此类转换。它适用于 IPv4 和 IPv6。

CREATE OR REPLACE PACKAGE IP_Util AS

/**
* Convert an IP-Address into decimal value.
* @param IP The IP-Address, e.g. '10.151.20.224' or '1080::8:800:200C:417A'. 
* Supports also mixed notation like '0:0:0:0:0:FFFF:129.144.52.38'. CIDR value (e.g. '1080::8:800:200C:417A/80') is ignored.
* @return The decimal equivalent
*/
FUNCTION IP2Decimal(IP IN VARCHAR2) RETURN NUMBER DETERMINISTIC;

/**
* Convert an IP-Address into RWA value.
* @param IP The IP-Address, e.g. '10.151.20.224' or '1080::8:800:200C:417A'. 
* Supports also mixed notation like '0:0:0:0:0:FFFF:129.144.52.38'. CIDR value (e.g. '1080::8:800:200C:417A/80') is ignored.
* @param ver IP version, either 4 or 6. If NULL then function determines the IP version.
* @return The RAW equivalent
*/
FUNCTION IP2RAW(IP IN VARCHAR2, ver IN INTEGER DEFAULT NULL) RETURN RAW DETERMINISTIC;

/**
* Convert an IP-Address from decimal value into IPv4 or IPv6 format.
* @param ip Decimal IP-Address, 0..(2**32)-1 or 0..(2**128)-1
* @param ver IP version, either 4 or 6 
* @return The IP in IPv4 or IPv6 format
*/    
FUNCTION Decimal2IP(ip IN NUMBER, ver IN INTEGER) RETURN VARCHAR2 DETERMINISTIC;    


/**
* Convert an IP-Address from RAW value into IPv4 or IPv6 format.
* @param ip RAW value of IP-Address, 0..FFFFFFFF or 0..FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
* @param ver IP version, either 4 or 6 
* @return The IP in IPv4 or IPv6 format
*/    
FUNCTION RAW2IP(ip IN RAW, ver IN INTEGER) RETURN VARCHAR2 DETERMINISTIC;   

/**
* Returns SubnetMask of given IP-Subnet in CIDR notation.
* @param Ip Subnet IP-Address with CIDR notation, e.g. '10.152.10.17/24' or '1080::8:800:200C:417A/60'
* @return SubnetMask Subnet mask of IP-Subnet, e.g. '255.255.255.0' or 'ffff:ffff:ffff::'
*/
FUNCTION SubnetMask(Ip IN VARCHAR2) RETURN VARCHAR2 DETERMINISTIC;

/**
* Returns Network prefix of given IP-Subnet. In IPv4 this address was called subnet address.
* @param Ip IP-Address of subnet, e.g. '10.152.10.17' or '1080:0:100:8:800:200C:FFFF:417A'
* @param SubnetMask Subnet mask of subnet, e.g. '255.255.0.0' or 'FFFF:FFFF:FFFF::'
* @return Network prefix, i.e. the first address from subnet, for example '10.152.0.0' or '1080:0:100:8:800:200C:FFFF::'
*/
FUNCTION NetworkPrefix(Ip IN VARCHAR2, SubnetMask IN VARCHAR2) RETURN VARCHAR2 DETERMINISTIC;

/**
* Returns Network prefix of given IP-Subnet. In IPv4 this address was called subnet address.
* @param Ip IP-Subnet with CIDR notation, e.g. '10.152.10.17/24' or '1080:0:100:8:800:200C:FFFF:417A/60'
* @return Network prefix, i.e. the first address from subnet, for example '10.152.0.0' or '1080:0:100:8:800:200C:FFFF::'
*/
FUNCTION NetworkPrefix(Ip IN VARCHAR2) RETURN VARCHAR2 DETERMINISTIC;

/**
* Returns Broadcast address of given IP-Subnet. 
* IPv6 does not provide Broadcast anymore. However, function supports IPv6 for internal purpose.
* @param Ip IP-Address of subnet, e.g. '10.152.10.17' or '1080:0:100:8:800:200C:FFFF:417A'
* @param SubnetMask Subnet mask of subnet, e.g. '255.255.0.0' or 'FFFF:FFFF:FFFF::'
* @return Broadcast address, i.e. the last address from subnet, for example '10.152.10.255' or '1080:0:100:8:800:ffff:ffff:ffff'
*/
FUNCTION BroadcastIp(Ip IN VARCHAR2, SubnetMask IN VARCHAR2) RETURN VARCHAR2 DETERMINISTIC;

/**
* Returns Broadcast address of given IP-Subnet.   
* IPv6 does not provide Broadcast anymore. However, function supports IPv6 for internal purpose.
* @param Ip IP-Subnet with CIDR notation, e.g. '10.152.10.17/24' or '1080:0:100:8:800:200C:FFFF:417A/60'
* @return Broadcast address, i.e. the last address from subnet, for example '10.152.10.255' or '1080:0:100:8:800:ffff:ffff:ffff'
*/    
FUNCTION BroadcastIp(Ip IN VARCHAR2) RETURN VARCHAR2 DETERMINISTIC;

/**
* Translate Subnet mask to CIDR.
* @param SubnetMask Subnet mask of subnet, e.g. '255.255.0.0' or 'FFFF:FFFF:FFFF::'
* @return CIDR value, e.g. 26
*/    
FUNCTION SubnetMask2CIDR(SubnetMask VARCHAR2) RETURN INTEGER RESULT_CACHE DETERMINISTIC;

/**
* Translate CIDR to Subnet mask in IPv4 or IPv6 format.
* @param CIDR Length of network prefix
* @param ver IP version, either 4 or 6 
* @return Subnet mask, e.g. '255.255.0.0' or 'FFFF:FFFF:FFFF::'
*/
FUNCTION CIDR2SubnetMask(CIDR IN INTEGER, ver IN INTEGER) RETURN VARCHAR2 RESULT_CACHE DETERMINISTIC;

/**
* Returns full uncompressed IPv6 Address. Mainly used for internal purpose like conversion, storage, comparison, etc.
* '::' is replaced by zero pads, leading '0' are inserted (if leadingZero = TRUE), converted to lower cases. 
* @param Ip Compact IPv6-Address (with CIDR or without CIDR, e.g. 2620:0:2D0:A2A2::7)
* @param leadingZero If TRUE then bit fields are padded with '0' in order to have always 4 characters 
* @return The full IPv6 Address with 8 x 16 bits, e.g. '2620:0000:02d0:a2a2:0000:0000:0000:0007'
*/
FUNCTION UncompressIpV6(Ip IN VARCHAR2, leadingZero IN BOOLEAN DEFAULT TRUE) RETURN VARCHAR2 DETERMINISTIC;

/**
* Makes an canonical IPv6 address according to RFC 5952, i.e. human readable.
* @param IPv6 IPv6-Address (with or without '::', with or without leading '0')
* @return Canonical IPv6 Address, e.g. 2620:0:2d0:200::7
*/
FUNCTION Canonical_IPv6(IPv6 IN VARCHAR2) RETURN VARCHAR2 DETERMINISTIC;


END IP_Util;
/


CREATE OR REPLACE PACKAGE BODY IP_Util AS


NUMERIC_OVERFLOW EXCEPTION;
PRAGMA EXCEPTION_INIT(NUMERIC_OVERFLOW, -1426);



FUNCTION IP2Decimal(IP IN VARCHAR2) RETURN NUMBER DETERMINISTIC IS
    DecimalIp NUMBER; -- INTEGER does not cover (2**128)-1
BEGIN
    
    IF REGEXP_LIKE(IP, ':') THEN
        -- IPv6 Address
        IF REGEXP_LIKE(IP, '\d+\.\d+\.\d+\.\d+') THEN
            -- Mixed notation, e.g.: 0:0:0:0:0:FFFF:129.144.52.38
            SELECT SUM(TO_NUMBER(REGEXP_SUBSTR(UncompressIpV6(IP), '[[:xdigit:]]+', 1, LEVEL), 'XXXX') * POWER(65536, 8-LEVEL))
            INTO DecimalIp
            FROM dual 
            CONNECT BY LEVEL <= 6;

            SELECT DecimalIp + SUM(REGEXP_SUBSTR(REGEXP_SUBSTR(UncompressIpV6(IP), '\d+\.\d+\.\d+\.\d+'), '\d+', 1, LEVEL) * POWER(256, 4-LEVEL))
            INTO DecimalIp
            FROM dual 
            CONNECT BY LEVEL <= 4;
            RETURN DecimalIp;       
        ELSE
            SELECT SUM(TO_NUMBER(REGEXP_SUBSTR(UncompressIpV6(IP), '[[:xdigit:]]+', 1, LEVEL), 'XXXX') * POWER(65536, 8-LEVEL))
            INTO DecimalIp
            FROM dual 
            CONNECT BY LEVEL <= 8;
            RETURN DecimalIp;
        END IF;
    ELSE
        -- IPv4 Address
        SELECT SUM(REGEXP_SUBSTR(IP, '\d+', 1, LEVEL) * POWER(256, 4-LEVEL))
        INTO DecimalIp
        FROM dual 
        CONNECT BY LEVEL <= 4;
        RETURN DecimalIp;   
    END IF;

END IP2Decimal;



FUNCTION IP2RAW(IP IN VARCHAR2, ver IN INTEGER DEFAULT NULL) RETURN RAW DETERMINISTIC IS
BEGIN
    IF ver IS NULL THEN
        IF REGEXP_LIKE(IP, ':') THEN
            RETURN IP2RAW(IP, 6);
        ELSE    
            RETURN IP2RAW(IP, 4);
        END IF;
    ELSE
        IF ver = 6 THEN
            RETURN HEXTORAW(LPAD(TO_CHAR(IP2Decimal(ip), 'fmXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX'), 32, '0'));
        ELSIF ver = 4 THEN  
            RETURN HEXTORAW(LPAD(TO_CHAR(IP2Decimal(ip), 'fmXXXXXXXX'), 8, '0'));
        ELSE
            RAISE VALUE_ERROR;
        END IF;
    END IF;
END IP2RAW;



FUNCTION RAW2IP(ip IN RAW, ver IN INTEGER) RETURN VARCHAR2 DETERMINISTIC IS
    res VARCHAR2(45);
BEGIN
    -- Range check "TO_NUMBER(ip, 'XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX') < 2**32, resp 2**128" not needed, because RAW values are usually not based on error-prone user input
    IF ver = 4 THEN
        -- Take only last 32 bit from RAW value with UTL_RAW.SUBSTR(ip, -4)
        SELECT LISTAGG(TO_NUMBER(SUBSTR(SUBSTR(LPAD(RAWTOHEX(UTL_RAW.SUBSTR(ip, -4)), 8, '0'), -8), 2*LEVEL-1, 2), 'XX'), '.') WITHIN GROUP (ORDER BY LEVEL)
        INTO res
        FROM DUAL
        CONNECT BY LEVEL <= 4;
        RETURN res;
    ELSIF ver = 6 THEN
        RETURN Canonical_IPv6(SUBSTR(REGEXP_REPLACE(LPAD(RAWTOHEX(ip), 32, '0'), '([[:xdigit:]]{4})', ':\1'), 2));
    ELSE
        RAISE VALUE_ERROR;
    END IF;
END RAW2IP;



FUNCTION Decimal2IP(ip IN NUMBER, ver IN INTEGER) RETURN VARCHAR2 DETERMINISTIC IS
    res VARCHAR2(45);
BEGIN
    IF ip IS NULL THEN 
        RETURN NULL; 
    END IF;

    IF ver = 4 THEN
        IF ip > 2**32 - 1 THEN
            RAISE NUMERIC_OVERFLOW;
        END IF;
        
        SELECT LISTAGG(TO_NUMBER(SUBSTR(LPAD(TO_CHAR(ip, 'fmXXXXXXXX'), 8, '0'), 2*LEVEL-1, 2), 'XX'), '.') WITHIN GROUP (ORDER BY LEVEL)
        INTO res
        FROM dual
        CONNECT BY LEVEL <= 4;
        RETURN res;
    ELSIF ver = 6 THEN
        IF ip > 2**128 - 1 THEN
            RAISE NUMERIC_OVERFLOW;
        END IF;
        
        res := LPAD(TO_CHAR(ip, 'fmxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx'),32, '0');
        RETURN Canonical_IPv6(SUBSTR(REGEXP_REPLACE(res, '([[:xdigit:]]{4})', ':\1'), 2));
    ELSE
        RAISE VALUE_ERROR;
    END IF;
    
END Decimal2IP;



FUNCTION SubnetMask(Ip IN VARCHAR2) RETURN VARCHAR2 DETERMINISTIC IS
BEGIN
    IF Ip IS NULL OR NOT REGEXP_LIKE(Ip, '/\d{1,3}$') THEN
        RETURN NULL;
    END IF;
    IF REGEXP_LIKE(Ip, ':') THEN
        RETURN CIDR2SubnetMask(REGEXP_SUBSTR(Ip, '\d{1,3}$'), 6);
    ELSE
        RETURN CIDR2SubnetMask(REGEXP_SUBSTR(Ip, '\d{1,2}$'), 4);
    END IF; 
END SubnetMask;




FUNCTION NetworkPrefix(Ip IN VARCHAR2, SubnetMask IN VARCHAR2) RETURN VARCHAR2 DETERMINISTIC IS
BEGIN
    IF REGEXP_LIKE(ip, ':') THEN
        RETURN RAW2IP(UTL_RAW.BIT_AND(Ip2RAW(Ip, 6), Ip2RAW(SubnetMask, 6)), 6);
    ELSE
        RETURN RAW2IP(UTL_RAW.BIT_AND(Ip2RAW(Ip, 4),Ip2RAW(SubnetMask, 4)), 4);
    END IF;
END NetworkPrefix;


FUNCTION NetworkPrefix(Ip IN VARCHAR2) RETURN VARCHAR2 DETERMINISTIC IS
BEGIN   
    RETURN NetworkPrefix(REGEXP_REPLACE(Ip, '/\d{1,3}$'), SubnetMask(Ip));
END NetworkPrefix;



FUNCTION BroadcastIp(Ip IN VARCHAR2, SubnetMask IN VARCHAR2) RETURN VARCHAR2 DETERMINISTIC IS
    Subnet RAW(16);
    SubnetInv RAW(16);
BEGIN   
    IF REGEXP_LIKE(ip, ':') THEN
        Subnet := UTL_RAW.BIT_AND(Ip2RAW(Ip, 6), Ip2RAW(SubnetMask, 6));
        SubnetInv := UTL_RAW.BIT_COMPLEMENT(Ip2RAW(SubnetMask, 6));     
        RETURN RAW2IP(UTL_RAW.BIT_OR(Subnet, SubnetInv), 6);
    ELSE    
        Subnet := UTL_RAW.BIT_AND(Ip2RAW(Ip, 4), Ip2RAW(SubnetMask, 4));
        SubnetInv := UTL_RAW.BIT_COMPLEMENT(Ip2RAW(SubnetMask, 4));     
        RETURN RAW2IP(UTL_RAW.BIT_OR(Subnet, SubnetInv), 4);
    END IF;
END BroadcastIp;


FUNCTION BroadcastIp(Ip IN VARCHAR2) RETURN VARCHAR2 DETERMINISTIC IS
BEGIN
    RETURN BroadcastIp(REGEXP_REPLACE(Ip, '/\d{1,3}$'), SubnetMask(Ip));
END BroadcastIp;



FUNCTION SubnetMask2CIDR(SubnetMask VARCHAR2) RETURN INTEGER RESULT_CACHE DETERMINISTIC IS
    ip RAW(16);
    cidr INTEGER;
BEGIN
    IF SubnetMask IS NULL THEN
        RETURN NULL;
    END IF; 
        
    IF REGEXP_LIKE(SubnetMask, ':') THEN
        ip := IP2RAW(SubnetMask, 6);
        cidr := 128-LOG(2, TO_NUMBER(UTL_RAW.BIT_COMPLEMENT(ip), 'XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX')+1);
    ELSE
        ip := IP2RAW(SubnetMask, 4);
        cidr := 32-LOG(2, TO_NUMBER(UTL_RAW.BIT_COMPLEMENT(ip), 'XXXXXXXX')+1);
    END IF;
    RETURN cidr;

END SubnetMask2CIDR;



FUNCTION CIDR2SubnetMask(CIDR IN INTEGER, ver IN INTEGER) RETURN VARCHAR2 RESULT_CACHE DETERMINISTIC IS
BEGIN
    IF CIDR IS NULL THEN
        RETURN NULL;
    END IF;
    
    IF ver = 4 THEN
        IF CIDR NOT BETWEEN 0 AND 32 THEN
            RAISE VALUE_ERROR;
        END IF;
        RETURN RAW2IP(UTL_RAW.BIT_COMPLEMENT(HEXTORAW(LPAD(TO_CHAR(2**(32-cidr)-1, 'fmXXXXXXXX'),8 , '0'))), 4);
    ELSIF ver = 6 THEN
        IF CIDR NOT BETWEEN 0 AND 128 THEN
            RAISE VALUE_ERROR;
        END IF; 
        RETURN RAW2IP(UTL_RAW.BIT_COMPLEMENT(HEXTORAW(LPAD(TO_CHAR(2**(128-cidr)-1, 'fmXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX'),32 , '0'))), 6);     
    ELSE
        RAISE VALUE_ERROR;
    END IF;
END CIDR2SubnetMask;




FUNCTION UncompressIpV6(Ip IN VARCHAR2, leadingZero IN BOOLEAN DEFAULT TRUE) RETURN VARCHAR2 DETERMINISTIC IS
    IpFull VARCHAR2(50);
    len INTEGER := 7;
    TYPE VARCHAR_TABLE_TYPE IS TABLE OF VARCHAR2(10);
    BitFields VARCHAR_TABLE_TYPE;
    cidr VARCHAR2(5);
BEGIN
    IF NOT REGEXP_LIKE(Ip, ':') THEN
        RETURN Ip;
    END IF;
    
    cidr := REGEXP_SUBSTR(Ip, '/\d{1,3}$');
    IpFull := REGEXP_REPLACE(Ip, '/\d{1,3}$');
    
    IF REGEXP_LIKE(IpFull, '::') THEN
        IpFull := REGEXP_REPLACE(REGEXP_REPLACE(IpFull, '^::', '0::'), '::$', '::0');
        IF REGEXP_LIKE(IpFull, ':\d+\.\d+\.\d+\.\d+') THEN
            -- Mixed notation, e.g.: 2002::FFFF:129.144.52.38
            len := 6;
        END IF;
        WHILE REGEXP_COUNT(IpFull, ':') <= len LOOP
            IpFull := REGEXP_REPLACE(IpFull, '::', ':0::');
        END LOOP;   
        IpFull := REGEXP_REPLACE(IpFull, '::', ':');
    END IF;

    IF NOT leadingZero THEN
        RETURN LOWER(IpFull||cidr);
    END IF;
    
    SELECT REGEXP_SUBSTR(IpFull, '[^:]+', 1, LEVEL) 
    BULK COLLECT INTO BitFields
    FROM dual
    CONNECT BY REGEXP_SUBSTR(IpFull, '[^:]+', 1, LEVEL) IS NOT NULL;
    
    IpFull := LPAD(BitFields(1), 4, '0');
    FOR i IN 2..BitFields.COUNT LOOP
        IF REGEXP_LIKE(BitFields(i), '\d+\.\d+\.\d+\.\d+') THEN
            IpFull := IpFull ||':'||BitFields(i);
        ELSE
            IpFull := IpFull ||':'||LPAD(BitFields(i), 4, '0');
        END IF;
    END LOOP;
    RETURN LOWER(IpFull)||cidr;

END UncompressIpV6;



FUNCTION Canonical_IPv6(IPv6 IN VARCHAR2) RETURN VARCHAR2 DETERMINISTIC IS
    res VARCHAR2(50);
    cidr VARCHAR2(5);
BEGIN       
    IF NOT REGEXP_LIKE(IPv6, ':') THEN
        RETURN IPv6;
    ELSIF REGEXP_LIKE(IPv6, '::') THEN
        -- Do not shorten twice
        res := UncompressIpV6(IPv6, FALSE);
    ELSE
        -- RFC 5952 section-4.3
        res := LOWER(IPv6);
    END IF;
    
    -- Split CIDR if existing
    cidr := REGEXP_SUBSTR(res, '/\d{1,3}$');
    res := REGEXP_REPLACE(res, '/\d{1,3}$');
    
    -- remove leading '0', RFC 5952 section-4.1
    res := REGEXP_REPLACE(res, '(:|^)0+([[:xdigit:]]+)', '\1\2');
    
    WITH ip AS
        -- split IP into 16-bit fields
        (SELECT REGEXP_SUBSTR(res, '[^:]+', 1, LEVEL) AS val, LEVEL AS pos
        FROM DUAL
        CONNECT BY REGEXP_SUBSTR(res, '[^:]+', 1, LEVEL) IS NOT NULL),
    p AS 
        -- find consecutive (at least 2) 0 fields, RFC 5952 section-4.2.2
        (SELECT pos, len, match_num
        FROM ip
        MATCH_RECOGNIZE (
            ORDER BY pos
            MEASURES 
                FINAL COUNT(*) AS len,
                MATCH_NUMBER() AS match_num
            ALL ROWS PER MATCH
            PATTERN(zero{2,})
            DEFINE zero AS val = '0')
        ),      
    m AS 
        -- select longest run of consecutive 0 fields, RFC 5952 section-4.2.3
        (SELECT * FROM p WHERE len = (SELECT MAX(len) FROM p)),
    f AS 
        -- select first sequence of longest run of consecutive 0 fields, RFC 5952 section-4.2.3
        (SELECT * FROM m WHERE match_num = (SELECT MIN(match_num) FROM m))
    SELECT REGEXP_REPLACE(LISTAGG(NVL2(match_num, ':', val), ':') WITHIN GROUP (ORDER BY pos), ':{2,}', '::')
    INTO res
    FROM ip
        LEFT OUTER JOIN f USING (pos);
    RETURN res||cidr;

END Canonical_IPv6;


END IP_Util;
/

然后你可以像这样使用它:

SELECT 
   IP_Util.NetworkPrefix('2620:0:2d0:200::7/32'), 
   IP_Util.BroadcastIp('2620:0:2d0:200::7/32') 
FROM dual;


2620::    2620:0:ffff:ffff:ffff:ffff:ffff:ffff

如果您喜欢 2620:0:0:0:0:0:0:0 则使用

IP_Util.UncompressIpV6(IP_Util.NetworkPrefix('2620:0:2d0:200::7/32'), false)

然而，根据RFC 5952 2620:: 将是首选格式。

下面是几个如何使用这个包的例子:

-- Determine if (IPv4) Address is a Private IP:
CREATE OR REPLACE FUNCTION IsPrivate_IP(ip IN VARCHAR2) RETURN NUMBER DETERMINISTIC IS
BEGIN
    IF IP_Util.NetworkPrefix('10.0.0.0', '255.0.0.0') = IP_Util.NetworkPrefix(ip, '255.0.0.0') THEN
        RETURN 1;
    ELSIF IP_Util.NetworkPrefix('172.16.0.0', '255.240.0.0') = IP_Util.NetworkPrefix(ip, '255.240.0.0') THEN
        RETURN 1;
    ELSIF IP_Util.NetworkPrefix('192.168.0.0', '255.255.0.0') = IP_Util.NetworkPrefix(ip, '255.255.0.0') THEN
        RETURN 1;
    ELSE
        RETURN 0;
    END IF;

END IsPrivate_IP;

或者更复杂的使用 6to4 和 6RD 网络前缀将 IPv4 转换为 IPv6，反之亦然:

CREATE OR REPLACE FUNCTION NAT64(ip IN VARCHAR2, IpV6mask IN VARCHAR2 DEFAULT '::ffff:0:0') RETURN VARCHAR2 DETERMINISTIC IS
    shift INTEGER;
    cidr INTEGER;
    n NUMBER;
    a RAW(16);
    b RAW(16);
BEGIN
    IF REGEXP_LIKE(ip, ':') THEN
        -- Translate from IPv6 to IPv4
        IF NOT REGEXP_LIKE(IpV6mask, '/\d+{1,3}$') THEN
            RETURN IP_Util.RAW2IP(UTL_RAW.BIT_AND(IP_Util.IP2Raw(ip), HEXTORAW('000000000000000000000000FFFFFFFF')), 4);
        ELSE
            shift := 128 - REGEXP_SUBSTR(IpV6mask, '\d+{1,3}$');
            IF shift < 32 THEN 
                RAISE VALUE_ERROR;
            END IF;
            -- Generate mask for IPv4 address, e.g. '0000000000000000FFFFFFFF00000000'
            b := HEXTORAW(LPAD(TO_CHAR((2**shift-1) - (2**(shift-32)-1), 'fmXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX'),32 , '0'));
            n := TO_NUMBER(UTL_RAW.BIT_AND(IP_Util.IP2Raw(ip), b), 'XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX');
            -- UTL_RAW.SUBSTR does not work because you can shift only Bytes, I need Bits
            RETURN IP_Util.Decimal2IP(TRUNC(n / 2**(shift-32)), 4);
        END IF;
    ELSE
        -- Translate from IPv4 to IPv6
        IF NOT REGEXP_LIKE(IpV6mask, '/\d+{1,3}$') THEN
            a := UTL_RAW.BIT_AND(IP_Util.IP2Raw(IpV6mask), UTL_RAW.BIT_COMPLEMENT(HEXTORAW(LPAD(TO_CHAR(2**32-1 , 'fmXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX'),32 , '0'))));
            RETURN IP_Util.RAW2IP(UTL_RAW.BIT_OR(a, IP_Util.IP2RAW(ip, 6)), 6);
        ELSE
            cidr := REGEXP_SUBSTR(IpV6mask, '\d+{1,3}$');
            shift := 128 - 32 - cidr;
            IF shift < 0 THEN 
                RAISE VALUE_ERROR;
            END IF;

            a := UTL_RAW.BIT_AND(IP_Util.IP2Raw(IpV6mask), UTL_RAW.BIT_COMPLEMENT(HEXTORAW(LPAD(TO_CHAR(2**(128-cidr)-1 , 'fmXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX'),32 , '0'))));
            b := HEXTORAW(LPAD(TO_CHAR(2**shift * IP_Util.IP2Decimal(ip), 'fmXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX'),32 , '0'));
            RETURN IP_Util.RAW2IP(UTL_RAW.BIT_OR(a, b), 6);
        END IF;     
    END IF;
END NAT64;