How to Write custom IP address algorithms and custom IP address Algorithms

How to Write custom IP address algorithms and custom IP address Algorithms

Through the IP address, you can see the algorithm rule, write it as a custom IP address, or convert the IP address to a custom IP address. It can also be used to encrypt plaintext numbers. The following describes the positive and negative algorithms (in the unit of least one time ):

USE tempdbGOIF OBJECT_ID ('fn _ NrToChar ') is not null drop function fn_NrToCharGO /********************************* **************************************** **************************************** **************************************** * ****** % Function Name: fn_NrToChar % features: change the number to the character ************************************ **************************************** **************************************** **************************************** *** %: roy 2014-12-09 ************************************** **************************************** **************************************** **************************************** **/create function fn_NrToChar (@ Nr BIGINT, @ NrSystem BIGINT = 168 -- hexadecimal, @ Split VARCHAR (2) = '**' -- delimiter, @ PartCount BIGINT = 5 -- number of segments) returns varchar (50) as begindeclare @ s varchar (50) = ''while @ PartCount> 0 SELECT @ S = @ S + case when @ S> ''then @ Split ELSE ''END + RTRIM (@ Nr/POWER (@ NrSystem, @ PartCount), @ Nr = @ Nr % POWER (@ NrSystem, @ PartCount), @ PartCount = @ PartCount-1RETURN @ SENDGOIF OBJECT_ID ('fn _ CharToNr ') is not null drop function fn_CharToNrGO /********************************* **************************************** **************************************** **************************************** * ****** % Function Name: fn_CharToNr % features: change the character to a number ************************************ **************************************** **************************************** **************************************** *** %: roy 2014-12-09 ************************************** **************************************** **************************************** **************************************** **/create function fn_CharToNr (@ Str VARCHAR (50 ), @ NrSystem BIGINT = 168 -- hexadecimal, @ Split VARCHAR (2) = '**' -- delimiter, @ PartCount BIGINT = 5 -- number of segments) returns bigintas begindeclare @ Nr BIGINT = 0, @ StartLen TINYINT, @ StrLen TINYINTSELECT @ StrLen = LEN (@ Split ), @ StartLen = 1 WHILE @ PartCount> 0 SELECT @ Nr = @ Nr + SUBSTRING (@ Str, @ StartLen, CHARINDEX (@ Split, @ Str + @ Split, @ StartLen) -@ StartLen) * POWER (@ NrSystem, @ PartCount), @ StartLen = CHARINDEX (@ Split, @ Str + @ Split, @ StartLen) + @ StrLen, @ PartCount = @ PartCount-1RETURN @ NrENDGO -- test 1 (take IP address as an example) SELECT dbo. fn_CharToNr ('2017. 168.0.1 ', 256 ,'. ', 4) SELECT dbo. fn_NrToChar (827452293376,256 ,'. ', 4)/* 827452293376192.168.0.1 */go -- Test 2 DECLARE @ I BIGINT = 168 select power (@ I, 5) -- 133827821568 SELECT dbo. fn_CharToNr ('2017 ** 16 ** 1 ** 6 ** 07 ', DEFAULT, DEFAULT) SELECT dbo. fn_NrToChar (22361996620824, DEFAULT, DEFAULT)/* 22361996620824167 ** 16 ** 1 ** 6 ** 7 */