网络上关于这段代码的文章很多,但是注释及源码出处不详。这里我也没找到原始出处,只对代码做了简单的注释。
'VBA MD5 加密算法 '参考文档:http://www.faqs.org/rfcs/rfc1321.html '参考文档:https://github.com/vieyahn2017/iBlog/issues/378 'MD5信息摘要算法(Message-Digest Algorithm)以512位分组来处理输入的信息,且每一分组又被划分为16个32位子分组,经过了一系列的处理后,算法的输出由四个32位分组组成,将这四个32位分组级联后将生成一个128位散列值。 '第一步:填充补齐数据。要求填充后信息的长度就为 N*512+448(bit),填充的方法是填充一个1和n个0。 '第二步:记录信息长度。用64位来存储填充前信息长度。这64位加在第一步结果的后面,这样信息长度就变为N*512+448+64=(N+1)*512位。 '第三步:初始化MD缓存器:用来保存中间变量和最终结果。分别是(A=(01234567)16,B=(89ABCDEF)16,C=(FEDCBA98)16,D=(76543210)16),在程序中则为:(A=0X67452301L,B=0XEFCDAB89L,C=0X98BADCFEL,D=0X10325476L)。 '第四步:四轮循环运算:循环的次数是分组的个数(N+1)。 '4.1、定义4个非线性函数F、G、H、I,对输入的报文运算以512位数据段为单位进行处理。 '4.2、对每个数据段都要进行4轮的逻辑处理,在4轮中分别使用4个不同的函数F、G、H、I。每一轮以ABCD和当前的512位的块为输入,处理后送入ABCD(128位)。 Private Const BITS_TO_A_BYTE = 8 '一个字节的比特数 Private Const BYTES_TO_A_WORD = 4 '一个单元的字节数 Private Const BITS_TO_A_WORD = 32 '一个单元的比特数 Private m_lOnBits(30) Private m_l2Power(30) '向左移位 Private Function LShift(lValue, iShiftBits) If iShiftBits = 0 Then LShift = lValue Exit Function ElseIf iShiftBits = 31 Then If lValue And 1 Then LShift = &H80000000 Else LShift = 0 End If Exit Function ElseIf iShiftBits < 0 Or iShiftBits > 31 Then Err.Raise 6 End If If (lValue And m_l2Power(31 - iShiftBits)) Then LShift = ((lValue And m_lOnBits(31 - (iShiftBits + 1))) * m_l2Power(iShiftBits)) Or &H80000000 Else LShift = ((lValue And m_lOnBits(31 - iShiftBits)) * m_l2Power(iShiftBits)) End If End Function '向右移位 Private Function RShift(lValue, iShiftBits) If iShiftBits = 0 Then RShift = lValue Exit Function ElseIf iShiftBits = 31 Then If lValue And &H80000000 Then RShift = 1 Else RShift = 0 End If Exit Function ElseIf iShiftBits < 0 Or iShiftBits > 31 Then Err.Raise 6 End If RShift = (lValue And &H7FFFFFFE) \ m_l2Power(iShiftBits) If (lValue And &H80000000) Then RShift = (RShift Or (&H40000000 \ m_l2Power(iShiftBits - 1))) End If End Function '移动一定位数 Private Function RotateLeft(lValue, iShiftBits) RotateLeft = LShift(lValue, iShiftBits) Or RShift(lValue, (32 - iShiftBits)) End Function '累加函数 Private Function AddUnsigned(lX, lY) Dim lX4 Dim lY4 Dim lX8 Dim lY8 Dim lResult lX8 = lX And &H80000000 lY8 = lY And &H80000000 lX4 = lX And &H40000000 lY4 = lY And &H40000000 lResult = (lX And &H3FFFFFFF) + (lY And &H3FFFFFFF) If lX4 And lY4 Then lResult = lResult Xor &H80000000 Xor lX8 Xor lY8 ElseIf lX4 Or lY4 Then If lResult And &H40000000 Then lResult = lResult Xor &HC0000000 Xor lX8 Xor lY8 Else lResult = lResult Xor &H40000000 Xor lX8 Xor lY8 End If Else lResult = lResult Xor lX8 Xor lY8 End If AddUnsigned = lResult End Function '第四步:四轮循环运算 '定义4个非线性函数F、G、H、I,对输入的报文运算以512位数据段为单位进行处理。 '非线性函数md5_F # 第一种形式 Private Function md5_F(x, y, z) md5_F = (x And y) Or ((Not x) And z) End Function '非线性函数md5_G # 第二种形式 Private Function md5_G(x, y, z) md5_G = (x And z) Or (y And (Not z)) End Function '非线性函数md5_H # 第三种形式 Private Function md5_H(x, y, z) md5_H = (x Xor y Xor z) End Function '非线性函数md5_I # 第四种形式 Private Function md5_I(x, y, z) md5_I = (y Xor (x Or (Not z))) End Function '第四步:四轮循环运算 '四个处理函数的参数均为 (a, b, c, d, M, S, K) 'a, b, c, d:初始化MD缓存器 '明文 M:即 x 表示第 x 组第 k + n 个 int 数,它是一个 32bits 的明文数据,跟 A/B/C/D 长度相同,也是一个 word 的大小。 '位移 S:即 s 表示令 X <<< s 表示通过将 X 向左循环移位(旋转)s 个位而获得的 32 位值。 '正弦函数表K:即 ac ,共有 64 个常量数值,每个数值长度 32bits。 '处理函数 md5_FF # 第一种形式: Private Sub md5_FF(a, b, c, d, x, s, ac) a = AddUnsigned(a, AddUnsigned(AddUnsigned(md5_F(b, c, d), x), ac)) a = RotateLeft(a, s) a = AddUnsigned(a, b) End Sub '处理函数 md5_GG # 第二种形式: Private Sub md5_GG(a, b, c, d, x, s, ac) a = AddUnsigned(a, AddUnsigned(AddUnsigned(md5_G(b, c, d), x), ac)) a = RotateLeft(a, s) a = AddUnsigned(a, b) End Sub '处理函数 md5_HH # 第三种形式: Private Sub md5_HH(a, b, c, d, x, s, ac) a = AddUnsigned(a, AddUnsigned(AddUnsigned(md5_H(b, c, d), x), ac)) a = RotateLeft(a, s) a = AddUnsigned(a, b) End Sub '处理函数 md5_II # 第四种形式: Private Sub md5_II(a, b, c, d, x, s, ac) a = AddUnsigned(a, AddUnsigned(AddUnsigned(md5_I(b, c, d), x), ac)) a = RotateLeft(a, s) a = AddUnsigned(a, b) End Sub '第一步:填充补齐数据 '第二步:记录信息长度 '最终以 512 位分组明文数据 Private Function ConvertToWordArray(sMessage) Dim lMessageLength Dim lNumberOfWords Dim lWordArray() Dim lBytePosition Dim lByteCount Dim lWordCount Const MODULUS_BITS = 512 Const CONGRUENT_BITS = 448 lMessageLength = Len(sMessage) lNumberOfWords = (((lMessageLength + ((MODULUS_BITS - CONGRUENT_BITS) \ BITS_TO_A_BYTE)) \ (MODULUS_BITS \ BITS_TO_A_BYTE)) + 1) * (MODULUS_BITS \ BITS_TO_A_WORD) ReDim lWordArray(lNumberOfWords - 1) lBytePosition = 0 lByteCount = 0 Do Until lByteCount >= lMessageLength lWordCount = lByteCount \ BYTES_TO_A_WORD lBytePosition = (lByteCount Mod BYTES_TO_A_WORD) * BITS_TO_A_BYTE lWordArray(lWordCount) = lWordArray(lWordCount) Or LShift(Asc(Mid(sMessage, lByteCount + 1, 1)), lBytePosition) lByteCount = lByteCount + 1 Loop lWordCount = lByteCount \ BYTES_TO_A_WORD lBytePosition = (lByteCount Mod BYTES_TO_A_WORD) * BITS_TO_A_BYTE lWordArray(lWordCount) = lWordArray(lWordCount) Or LShift(&H80, lBytePosition) lWordArray(lNumberOfWords - 2) = LShift(lMessageLength, 3) lWordArray(lNumberOfWords - 1) = RShift(lMessageLength, 29) ConvertToWordArray = lWordArray End Function 'Word转成16进制 Private Function WordToHex(lValue) Dim lByte Dim lCount For lCount = 0 To 3 lByte = RShift(lValue, lCount * BITS_TO_A_BYTE) And m_lOnBits(BITS_TO_A_BYTE - 1) WordToHex = WordToHex & Right("0" & Hex(lByte), 2) Next End Function '输出 MD5 加密后的结果 Public Function MD5(sMessage, iType) m_lOnBits(0) = CLng(1) m_lOnBits(1) = CLng(3) m_lOnBits(2) = CLng(7) m_lOnBits(3) = CLng(15) m_lOnBits(4) = CLng(31) m_lOnBits(5) = CLng(63) m_lOnBits(6) = CLng(127) m_lOnBits(7) = CLng(255) m_lOnBits(8) = CLng(511) m_lOnBits(9) = CLng(1023) m_lOnBits(10) = CLng(2047) m_lOnBits(11) = CLng(4095) m_lOnBits(12) = CLng(8191) m_lOnBits(13) = CLng(16383) m_lOnBits(14) = CLng(32767) m_lOnBits(15) = CLng(65535) m_lOnBits(16) = CLng(131071) m_lOnBits(17) = CLng(262143) m_lOnBits(18) = CLng(524287) m_lOnBits(19) = CLng(1048575) m_lOnBits(20) = CLng(2097151) m_lOnBits(21) = CLng(4194303) m_lOnBits(22) = CLng(8388607) m_lOnBits(23) = CLng(16777215) m_lOnBits(24) = CLng(33554431) m_lOnBits(25) = CLng(67108863) m_lOnBits(26) = CLng(134217727) m_lOnBits(27) = CLng(268435455) m_lOnBits(28) = CLng(536870911) m_lOnBits(29) = CLng(1073741823) m_lOnBits(30) = CLng(2147483647) m_l2Power(0) = CLng(1) m_l2Power(1) = CLng(2) m_l2Power(2) = CLng(4) m_l2Power(3) = CLng(8) m_l2Power(4) = CLng(16) m_l2Power(5) = CLng(32) m_l2Power(6) = CLng(64) m_l2Power(7) = CLng(128) m_l2Power(8) = CLng(256) m_l2Power(9) = CLng(512) m_l2Power(10) = CLng(1024) m_l2Power(11) = CLng(2048) m_l2Power(12) = CLng(4096) m_l2Power(13) = CLng(8192) m_l2Power(14) = CLng(16384) m_l2Power(15) = CLng(32768) m_l2Power(16) = CLng(65536) m_l2Power(17) = CLng(131072) m_l2Power(18) = CLng(262144) m_l2Power(19) = CLng(524288) m_l2Power(20) = CLng(1048576) m_l2Power(21) = CLng(2097152) m_l2Power(22) = CLng(4194304) m_l2Power(23) = CLng(8388608) m_l2Power(24) = CLng(16777216) m_l2Power(25) = CLng(33554432) m_l2Power(26) = CLng(67108864) m_l2Power(27) = CLng(134217728) m_l2Power(28) = CLng(268435456) m_l2Power(29) = CLng(536870912) m_l2Power(30) = CLng(1073741824) Dim x Dim k Dim AA Dim BB Dim CC Dim DD Dim a Dim b Dim c Dim d '0~15次对应的移位数组 [7, 12, 17, 22] Const S11 = 7 Const S12 = 12 Const S13 = 17 Const S14 = 22 '16~31次对应的移位数组 [5, 9, 14, 20] Const S21 = 5 Const S22 = 9 Const S23 = 14 Const S24 = 20 '32~47次对应的移位数组 [4, 11, 16, 23] Const S31 = 4 Const S32 = 11 Const S33 = 16 Const S34 = 23 '48~63次对应的移位数组 [6, 10, 15, 21] Const S41 = 6 Const S42 = 10 Const S43 = 15 Const S44 = 21 '第一步:填充补齐数据 '第二步:记录信息长度 x = ConvertToWordArray(sMessage) '第三步:初始化MD缓存器 a = &H67452301 b = &HEFCDAB89 c = &H98BADCFE d = &H10325476 '第四步:四轮循环运算 For k = 0 To UBound(x) Step 16 AA = a BB = b CC = c DD = d '对每个数据段都要进行4轮的逻辑处理,在4轮中分别使用4个不同的函数F、G、H、I。每一轮以ABCD和当前的512位的块为输入,处理后送入ABCD(128位)。 '第一轮 md5_FF a, b, c, d, x(k + 0), S11, &HD76AA478 md5_FF d, a, b, c, x(k + 1), S12, &HE8C7B756 md5_FF c, d, a, b, x(k + 2), S13, &H242070DB md5_FF b, c, d, a, x(k + 3), S14, &HC1BDCEEE md5_FF a, b, c, d, x(k + 4), S11, &HF57C0FAF md5_FF d, a, b, c, x(k + 5), S12, &H4787C62A md5_FF c, d, a, b, x(k + 6), S13, &HA8304613 md5_FF b, c, d, a, x(k + 7), S14, &HFD469501 md5_FF a, b, c, d, x(k + 8), S11, &H698098D8 md5_FF d, a, b, c, x(k + 9), S12, &H8B44F7AF md5_FF c, d, a, b, x(k + 10), S13, &HFFFF5BB1 md5_FF b, c, d, a, x(k + 11), S14, &H895CD7BE md5_FF a, b, c, d, x(k + 12), S11, &H6B901122 md5_FF d, a, b, c, x(k + 13), S12, &HFD987193 md5_FF c, d, a, b, x(k + 14), S13, &HA679438E md5_FF b, c, d, a, x(k + 15), S14, &H49B40821 '第二轮 md5_GG a, b, c, d, x(k + 1), S21, &HF61E2562 md5_GG d, a, b, c, x(k + 6), S22, &HC040B340 md5_GG c, d, a, b, x(k + 11), S23, &H265E5A51 md5_GG b, c, d, a, x(k + 0), S24, &HE9B6C7AA md5_GG a, b, c, d, x(k + 5), S21, &HD62F105D md5_GG d, a, b, c, x(k + 10), S22, &H2441453 md5_GG c, d, a, b, x(k + 15), S23, &HD8A1E681 md5_GG b, c, d, a, x(k + 4), S24, &HE7D3FBC8 md5_GG a, b, c, d, x(k + 9), S21, &H21E1CDE6 md5_GG d, a, b, c, x(k + 14), S22, &HC33707D6 md5_GG c, d, a, b, x(k + 3), S23, &HF4D50D87 md5_GG b, c, d, a, x(k + 8), S24, &H455A14ED md5_GG a, b, c, d, x(k + 13), S21, &HA9E3E905 md5_GG d, a, b, c, x(k + 2), S22, &HFCEFA3F8 md5_GG c, d, a, b, x(k + 7), S23, &H676F02D9 md5_GG b, c, d, a, x(k + 12), S24, &H8D2A4C8A '第三轮 md5_HH a, b, c, d, x(k + 5), S31, &HFFFA3942 md5_HH d, a, b, c, x(k + 8), S32, &H8771F681 md5_HH c, d, a, b, x(k + 11), S33, &H6D9D6122 md5_HH b, c, d, a, x(k + 14), S34, &HFDE5380C md5_HH a, b, c, d, x(k + 1), S31, &HA4BEEA44 md5_HH d, a, b, c, x(k + 4), S32, &H4BDECFA9 md5_HH c, d, a, b, x(k + 7), S33, &HF6BB4B60 md5_HH b, c, d, a, x(k + 10), S34, &HBEBFBC70 md5_HH a, b, c, d, x(k + 13), S31, &H289B7EC6 md5_HH d, a, b, c, x(k + 0), S32, &HEAA127FA md5_HH c, d, a, b, x(k + 3), S33, &HD4EF3085 md5_HH b, c, d, a, x(k + 6), S34, &H4881D05 md5_HH a, b, c, d, x(k + 9), S31, &HD9D4D039 md5_HH d, a, b, c, x(k + 12), S32, &HE6DB99E5 md5_HH c, d, a, b, x(k + 15), S33, &H1FA27CF8 md5_HH b, c, d, a, x(k + 2), S34, &HC4AC5665 '第四轮 md5_II a, b, c, d, x(k + 0), S41, &HF4292244 md5_II d, a, b, c, x(k + 7), S42, &H432AFF97 md5_II c, d, a, b, x(k + 14), S43, &HAB9423A7 md5_II b, c, d, a, x(k + 5), S44, &HFC93A039 md5_II a, b, c, d, x(k + 12), S41, &H655B59C3 md5_II d, a, b, c, x(k + 3), S42, &H8F0CCC92 md5_II c, d, a, b, x(k + 10), S43, &HFFEFF47D md5_II b, c, d, a, x(k + 1), S44, &H85845DD1 md5_II a, b, c, d, x(k + 8), S41, &H6FA87E4F md5_II d, a, b, c, x(k + 15), S42, &HFE2CE6E0 md5_II c, d, a, b, x(k + 6), S43, &HA3014314 md5_II b, c, d, a, x(k + 13), S44, &H4E0811A1 md5_II a, b, c, d, x(k + 4), S41, &HF7537E82 md5_II d, a, b, c, x(k + 11), S42, &HBD3AF235 md5_II c, d, a, b, x(k + 2), S43, &H2AD7D2BB md5_II b, c, d, a, x(k + 9), S44, &HEB86D391 a = AddUnsigned(a, AA) b = AddUnsigned(b, BB) c = AddUnsigned(c, CC) d = AddUnsigned(d, DD) Next If iType = 32 Then MD5 = LCase(WordToHex(a) & WordToHex(b) & WordToHex(c) & WordToHex(d)) Else MD5 = LCase(WordToHex(b) & WordToHex(c)) End If End Function
使用方法:
在 Excel 中新建一个模块,将代码复制进去,然后使用 MD5(strMessage, intType) 生成加密后的字符串即可。
- strMsg:需要加密的明文
- intType:加密的类型,16位或32位
参考文档: