Batch Convert IP Addresses into Decimals? - bash

Question

I have a large file that contains 2 IPs per line - and there's about 3 million lines total.
Here's an example of the file:
1.32.0.0,1.32.255.255
5.72.0.0,5.75.255.255
5.180.0.0,5.183.255.255
222.127.228.22,222.127.228.23
222.127.228.24,222.127.228.24
I need to convert each IP to an IP Decimal, like this:
18874368,18939903
88604672,88866815
95682560,95944703
3732923414,3732923415
3732923416,3732923416
I'd prefer a way to do this strictly via command line. I'm okay with perl or python being used, as long as it doesn't require extra modules to be installed.
I thought I had come across a way that someone converted IPs like this using sed but can't seem to find that tutorial anymore. Any help would be appreciated.

Answer 1

If you have gnu awk installed (for the RT variable), you could use this one-liner:
awk -F. -v RS='[\n,]' '{printf "%d%s", (($1*256+$2)*256+$3)*256+$4, RT}' file
18874368,18939903
88604672,88866815
95682560,95944703
3732923414,3732923415
3732923416,3732923416

Answer 2

Here it is python solution, that use only standard modules (re, sys):
import re
import sys
def multiplier_generator():
""" Cyclic generator of powers of 256 (from 256**3 down to 256**0)
The mulitpliers tupple could be replaced by inline calculation
of power, but this approach has better performance.
"""
multipliers = (
256**3,
256**2,
256**1,
256**0,
)
idx = 0
while 1 == 1:
yield multipliers[idx]
idx = (idx + 1) % 4
def replacer(match_object):
"""re.sub replacer for ip group"""
multiplier = multiplier_generator()
res = 0
for i in xrange(1,5):
res += multiplier.next()*int(match_object.group(i))
return str(res)
if __name__ == "__main__":
std_in = ""
if len(sys.argv) > 1:
with open(sys.argv[1],'r') as f:
std_in = f.read()
else:
std_in = sys.stdin.read()
print re.sub(r"([0-9]+)\.([0-9]+)\.([0-9]+)\.([0-9]+)", replacer, std_in )
This solution replace every ip address, that can be found in text from standard input or from file passed as first parameter, i.e:
python convert.py < input_file.txt, or
python convert.py file.txt, or
echo "1.2.3.4, 5.6.7.8" | python convert.py.

Answer 3

With bash:
ip2dec() {
set -- ${1//./ } # split $1 with "." to $1 $2 $3 $4
declare -i dec # set integer attribute
dec=$1*256*256*256+$2*256*256+$3*256+$4
echo -n $dec
}
while IFS=, read -r a b; do ip2dec $a; echo -n ,; ip2dec $b; echo; done < file
Output:
18874368,18939903
88604672,88866815
95682560,95944703
3732923414,3732923415
3732923416,3732923416

Answer 4

With bash and using shift (one CPU instruction) instead of multiply (a lot of instructions):
ip2dec() { local IFS=.
set -- $1 # split $1 with "." to $1 $2 $3 $4
printf '%s' "$(($1<<24+$2<<16+$3<<8+$4))"
}
while IFS=, read -r a b; do
printf '%s,%s\n' "$(ip2dec $a)" "$(ip2dec $b)"
done < file