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Karthikeyan298/cidr_to_regex.py

Forked from 112buddyd/cidr_to_regex.py
Created July 3, 2018 13:21
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Python CIDR Notation to Regex Tool
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cidr_to_regex.py
def cidr_to_regex(cidr):
import re
# Validation
cidr_regex = r'^(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.){3}' \
'([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])(\/([0-9]|[1-2][0-9]|3[0-2]))$'
if not re.match(cidr_regex, cidr):
return 'Input not valid CIDR notation. Ex. 192.168.1.0/24'
# Setup Regex string dictionary
map = {}
# 255
map[0] = {}
map[0][0] = '[0-9]{1,3}'
# 128
map[1] = {}
map[1][0] = '([0-9]{0,1}[0-9]|1[0-1][0-9]|12[0-7])'
map[1][128] = '(12[8-9]|1[3-9][0-9]|2[0-5][0-9])'
# 64
map[2] = {}
map[2][0] = '([0-5]{0,1}[0-9]|6[0-3])'
map[2][64] = '(6[4-9]|[7-9][0-9]|1[0-1][0-9]|12[0-7])'
map[2][128] = '(12[8-9]|1[3-8][0-9]|19[0-1])'
map[2][192] = '(19[2-9]|2[0-5][0-9])'
# 32
map[3] = {}
map[3][0] = '([0-2]{0,1}[0-9]|3[0-1])'
map[3][32] = '(3[2-9]|[4-5][0-9]|6[0-3])'
map[3][64] = '(6[4-9]|[7-8][0-9]|9[0-5])'
map[3][96] = '(9[6-9]|1[0-1][0-9]|12[0-7])'
map[3][128] = '(12[8-9]|1[3-5][0-9])'
map[3][160] = '(1[6-8][0-9]|19[0-1])'
map[3][192] = '(19[2-9]|2[0-1][0-9]|22[0-3])'
map[3][224] = '(22[4-9]|2[3-5][0-9])'
# 16
map[4] = {}
map[4][0] = '([0-9]|1[0-5])'
map[4][16] = '(1[6-9]|2[0-9]|3[0-1])'
map[4][32] = '(3[2-9]|4[0-7])'
map[4][48] = '(4[8-9]|5[0-9]|6[0-3])'
map[4][64] = '(6[4-9]|7[0-9])'
map[4][80] = '(8[0-9]|9[0-5])'
map[4][96] = '(9[6-9]|10[0-9]|11[0-1])'
map[4][112] = '(11[2-9]|12[0-7])'
map[4][128] = '(12[8-9]|13[0-9]|14[0-3])'
map[4][144] = '(14[4-9]|15[0-9])'
map[4][160] = '(16[0-9]|17[0-5])'
map[4][176] = '(17[6-9]|18[0-9]|19[0-1])'
map[4][192] = '(19[2-9]|20[0-7])'
map[4][208] = '(20[8-9]|21[0-9]|22[0-3])'
map[4][224] = '(22[4-9]|23[0-9])'
map[4][240] = '2[4-5][0-9]'
# 8
map[5] = {}
map[5][0] = '[0-7]'
map[5][8] = '([8-9]|1[0-5])'
map[5][16] = '(1[6-9]|2[0-3])'
map[5][24] = '(2[4-9]|3[0-1])'
map[5][32] = '3[2-9]'
map[5][40] = '4[0-7]'
map[5][48] = '(4[8-9]|5[0-5])'
map[5][56] = '(5[6-9]|6[0-3])'
map[5][64] = '(6[4-9]|7[0-1])'
map[5][72] = '7[2-9]'
map[5][80] = '8[0-7]'
map[5][88] = '(8[8-9]|9[0-5])'
map[5][96] = '(9[6-9]|10[0-3])'
map[5][104] = '(10[4-9]|11[0-1])'
map[5][112] = '11[2-9]'
map[5][120] = '12[0-7]'
map[5][128] = '(12[8-9]|13[0-5])'
map[5][136] = '(13[6-9]|14[0-3])'
map[5][144] = '(14[4-9]|15[0-1])'
map[5][152] = '15[2-9]'
map[5][160] = '16[0-7]'
map[5][168] = '(16[8-9]|17[0-5])'
map[5][176] = '(17[6-9]|18[0-3])'
map[5][184] = '(18[4-9]|19[0-1])'
map[5][192] = '19[2-9]'
map[5][200] = '20[0-7]'
map[5][208] = '(20[8-9]|21[0-5])'
map[5][216] = '(21[6-9]|22[0-3])'
map[5][224] = '(22[4-9]|23[0-1])'
map[5][232] = '23[2-9]'
map[5][240] = '24[0-7]'
map[5][248] = '(24[8-9]|25[0-5])'
# 4
map[6] = {}
map[6][0] = '[0-3]'
map[6][4] = '[4-7]'
map[6][8] = '([8-9]|1[0-1])'
map[6][12] = '1[2-5]'
map[6][16] = '1[6-9]'
map[6][20] = '2[0-3]'
map[6][24] = '2[4-7]'
map[6][28] = '(2[8-9]|3[0-1])'
map[6][32] = '3[2-5]'
map[6][36] = '3[6-9]'
map[6][40] = '4[0-3]'
map[6][44] = '4[4-7]'
map[6][48] = '(4[8-9]|5[0-1])'
map[6][52] = '5[2-5]'
map[6][56] = '5[6-9]'
map[6][60] = '6[0-3]'
map[6][64] = '6[4-7]'
map[6][68] = '(6[8-9]|7[0-1])'
map[6][72] = '7[2-5]'
map[6][76] = '7[6-9]'
map[6][80] = '8[0-3]'
map[6][84] = '8[4-7]'
map[6][88] = '(8[8-9]|9[0-1])'
map[6][92] = '9[2-5]'
map[6][96] = '9[6-9]'
map[6][100] = '10[0-3]'
map[6][104] = '10[4-7]'
map[6][108] = '(10[8-9]|11[0-1])'
map[6][112] = '11[2-5]'
map[6][116] = '11[6-9]'
map[6][120] = '12[0-3]'
map[6][124] = '12[4-7]'
map[6][128] = '(12[8-9]|13[0-1])'
map[6][132] = '13[2-5]'
map[6][136] = '13[6-9]'
map[6][140] = '14[0-3]'
map[6][144] = '14[4-7]'
map[6][148] = '(14[8-9]|15[0-1])'
map[6][152] = '15[2-5]'
map[6][156] = '15[6-9]'
map[6][160] = '16[0-3]'
map[6][164] = '16[4-7]'
map[6][168] = '(16[8-9]|17[0-1])'
map[6][172] = '17[2-5]'
map[6][176] = '17[6-9]'
map[6][180] = '18[0-3]'
map[6][184] = '18[4-7]'
map[6][188] = '(18[8-9]|19[0-1])'
map[6][192] = '19[2-5]'
map[6][196] = '19[6-9]'
map[6][200] = '20[0-3]'
map[6][204] = '20[4-7]'
map[6][208] = '(20[8-9]|21[0-1])'
map[6][212] = '21[2-5]'
map[6][216] = '21[6-9]'
map[6][220] = '22[0-3]'
map[6][224] = '22[4-7]'
map[6][228] = '(22[8-9]|23[0-1])'
map[6][232] = '23[2-5]'
map[6][236] = '23[6-9]'
map[6][240] = '24[0-3]'
map[6][244] = '24[4-7]'
map[6][248] = '(24[8-9]|25[0-1])'
map[6][252] = '25[2-5]'
# Setup some vars
network = cidr.split('/')[0]
n1 = cidr.split('.')[0]
n2 = cidr.split('.')[1]
n3 = cidr.split('.')[2]
n4 = cidr.split('.')[3]
mask = cidr.split('/')[1]
bip = 0
# Logic based on subnet mask
if mask == '0':
return map[0][0] + '\.' + map[0][0] + '\.' + map[0][0] + '\.' + map[0][0]
elif mask == '1':
bip = int((int(n1) / 128) * 128)
return map[1][bip] + '\.' + map[0][0] + '\.' + map[0][0] + '\.' + map[0][0]
elif mask == '2':
bip = int((int(n1) / 64) * 64)
return map[2][bip] + '\.' + map[0][0] + '\.' + map[0][0] + '\.' + map[0][0]
elif mask == '3':
bip = int((int(n1) / 32) * 32)
return map[3][bip] + '\.' + map[0][0] + '\.' + map[0][0] + '\.' + map[0][0]
elif mask == '4':
bip = int((int(n1) / 16) * 16)
return map[4][bip] + '\.' + map[0][0] + '\.' + map[0][0] + '\.' + map[0][0]
elif mask == '5':
bip = int((int(n1) / 8) * 8)
return map[5][bip] + '\.' + map[0][0] + '\.' + map[0][0] + '\.' + map[0][0]
elif mask == '6':
bip = int((int(n1) / 4) * 4)
return map[6][bip] + '\.' + map[0][0] + '\.' + map[0][0] + '\.' + map[0][0]
elif mask == '7':
bip = int((int(n1) / 2) * 2)
if len(str(bip)) == 2:
return str(bip)[0] + '[' + str(bip)[1] + '-' + str(bip + 1)[1] + ']' + '\.' + map[0][0] + '\.' + map[0][
0] + '\.' + map[0][0]
elif len(str(bip)) == 3:
return str(bip)[:2] + '[' + str(bip)[2] + '-' + str(bip + 1)[2] + ']' + '\.' + map[0][0] + '\.' + map[0][
0] + '\.' + map[0][0]
else:
return '[' + str(bip) + '-' + str(bip + 1) + ']' + '\.' + map[0][0] + '\.' + map[0][0] + '\.' + map[0][0]
elif mask == '8':
return n1 + '\.' + map[0][0] + '\.' + map[0][0] + '\.' + map[0][0]
elif mask == '9':
bip = int((int(n2) / 128) * 128)
return n1 + '\.' + map[1][bip] + '\.' + map[0][0] + '\.' + map[0][0]
elif mask == '10':
bip = int((int(n2) / 64) * 64)
return n1 + '\.' + map[2][bip] + '\.' + map[0][0] + '\.' + map[0][0]
elif mask == '11':
bip = int((int(n2) / 32) * 32)
return n1 + '\.' + map[3][bip] + '\.' + map[0][0] + '\.' + map[0][0]
elif mask == '12':
bip = int((int(n2) / 16) * 16)
return n1 + '\.' + map[4][bip] + '\.' + map[0][0] + '\.' + map[0][0]
elif mask == '13':
bip = int((int(n2) / 8) * 8)
return n1 + '\.' + map[5][bip] + '\.' + map[0][0] + '\.' + map[0][0]
elif mask == '14':
bip = int((int(n2) / 4) * 4)
return n1 + '\.' + map[6][bip] + '\.' + map[0][0] + '\.' + map[0][0]
elif mask == '15':
bip = int((int(n2) / 2) * 2)
if len(str(bip)) == 2:
return n1 + '\.' + str(bip)[0] + '[' + str(bip)[1] + '-' + str(bip + 1)[1] + ']' + '\.' + map[0][0] + '\.' + \
map[0][0]
elif len(str(bip)) == 3:
return n1 + '\.' + str(bip)[:2] + '[' + str(bip)[2] + '-' + str(bip + 1)[2] + ']' + '\.' + map[0][
0] + '\.' + map[0][0]
else:
return n1 + '\.' + '[' + str(bip) + '-' + str(bip + 1) + ']' + '\.' + map[0][0] + '\.' + map[0][0]
elif mask == '16':
return n1 + '\.' + n2 + '\.' + map[0][0] + '\.' + map[0][0]
elif mask == '17':
bip = int((int(n3) / 128) * 128)
return n1 + '\.' + n2 + '\.' + map[1][bip] + '\.' + map[0][0]
elif mask == '18':
bip = int((int(n3) / 64) * 64)
return n1 + '\.' + n2 + '\.' + map[2][bip] + '\.' + map[0][0]
elif mask == '19':
bip = int((int(n3) / 32) * 32)
return n1 + '\.' + n2 + '\.' + map[3][bip] + '\.' + map[0][0]
elif mask == '20':
bip = int((int(n3) / 16) * 16)
return n1 + '\.' + n2 + '\.' + map[4][bip] + '\.' + map[0][0]
elif mask == '21':
bip = int((int(n3) / 8) * 8)
return n1 + '\.' + n2 + '\.' + map[5][bip] + '\.' + map[0][0]
elif mask == '22':
print(n3)
bip = int((int(n3) / 4) * 4)
print(bip)
return n1 + '\.' + n2 + '\.' + map[6][bip] + '\.' + map[0][0]
elif mask == '23':
bip = int((int(n3) / 2) * 2)
if len(str(bip)) == 2:
return n1 + '\.' + n2 + '\.' + str(bip)[0] + '[' + str(bip)[1] + '-' + str(bip + 1)[1] + ']' + '\.' + \
map[0][0]
elif len(str(bip)) == 3:
return n1 + '\.' + n2 + '\.' + str(bip)[:2] + '[' + str(bip)[2] + '-' + str(bip + 1)[2] + ']' + '\.' + \
map[0][0]
else:
return n1 + '\.' + n2 + '\.' + '[' + str(bip) + '-' + str(bip + 1) + ']' + '\.' + map[0][0]
elif mask == '24':
return n1 + '\.' + n2 + '\.' + n3 + '\.' + map[0][0]
elif mask == '25':
bip = int((int(n4.split("/")[0]) / 128) * 128)
return n1 + '\.' + n2 + '\.' + n3 + '\.' + map[1][bip]
elif mask == '26':
bip = int((int(n4.split("/")[0]) / 64) * 64)
return n1 + '\.' + n2 + '\.' + n3 + '\.' + map[2][bip]
elif mask == '27':
bip = int((int(n4.split("/")[0]) / 32) * 32)
return n1 + '\.' + n2 + '\.' + n3 + '\.' + map[3][bip]
elif mask == '28':
bip = int((int(n4.split("/")[0]) / 16) * 16)
return n1 + '\.' + n2 + '\.' + n3 + '\.' + map[4][bip]
elif mask == '29':
bip = int((int(n4.split("/")[0]) / 8) * 8)
return n1 + '\.' + n2 + '\.' + n3 + '\.' + map[5][bip]
elif mask == '30':
bip = int((int(n4.split("/")[0]) / 4) * 4)
return n1 + '\.' + n2 + '\.' + n3 + '\.' + map[6][bip]
elif mask == '31':
bip = int((int(n4.split("/")[0]) / 2) * 2)
if len(str(bip)) == 2:
return n1 + '\.' + n2 + '\.' + n3 + '\.' + str(bip)[0] + '[' + str(bip)[1] + '-' + str(bip + 1)[
1] + ']'
elif len(str(bip)) == 3:
return n1 + '\.' + n2 + '\.' + n3 + '\.' + str(bip)[:2] + '[' + str(bip)[2] + '-' + str(bip + 1)[
2] + ']'
else:
return n1 + '\.' + n2 + '\.' + n3 + '\.' + '[' + str(bip) + '-' + str(bip + 1) + ']'
elif mask == '32':
return n1 + '\.' + n2 + '\.' + n3 + '\.' + n4.split("/")[0]
else:
return 'Invalid Subnet Mask.'
if __name__ == '__main__':
print(cidr_to_regex("10.11.12.12/24"))
@Karthikeyan298
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Author

Fixed some bugs in the
https://gist.github.com/Karthikeyan298/edcba4ffc5de5d81cae4cfc593619ef5#file-cidr_to_regex-py-L279
https://gist.github.com/Karthikeyan298/edcba4ffc5de5d81cae4cfc593619ef5#file-cidr_to_regex-py-L282

Changed [string] to str() and also added split to get the last subnet IPs from the given range for masks 25 to 31

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