I'm trying to create script that I can input a set of prefixes, which will then list all IP addresses within the prefixes (including network/host/broadcast).
An example would be:
./convert-prefix-to-IPs.sh 192.168.0.0/23 203.20.0.0/16
192.168.0.0
192.168.0.1
...
192.168.0.255
192.168.1.0
..
192.168.1.255
203.20.0.0
..
203.20.255.255
There are some python/perl scripts which can do this, but I'm hoping to have a simple bash script, as it may be used on systems without perl/python (yes.. i know.. )
Here is what I use to generate all the IP addresses in a given CIDR block
nmap -sL -n 10.10.64.0/27 | awk '/Nmap scan report/{print $NF}'
From the nmap man page, the flags are:
-sL: List Scan - simply list targets to scan
-n: Never do DNS resolution
Just that simple
The above command outputs this
10.10.64.0
10.10.64.1
10.10.64.2
10.10.64.3
10.10.64.4
10.10.64.5
10.10.64.6
10.10.64.7
10.10.64.8
10.10.64.9
10.10.64.10
10.10.64.11
10.10.64.12
10.10.64.13
10.10.64.14
10.10.64.15
10.10.64.16
10.10.64.17
10.10.64.18
10.10.64.19
10.10.64.20
10.10.64.21
10.10.64.22
10.10.64.23
10.10.64.24
10.10.64.25
10.10.64.26
10.10.64.27
10.10.64.28
10.10.64.29
10.10.64.30
10.10.64.31
I too was looking for this solution and found that #scherand script worked great. I also have added to this script to give you more option. Help File below.
THIS SCRIPT WILL EXPAND A CIDR ADDRESS.
SYNOPSIS
./cidr-to-ip.sh [OPTION(only one)] [STRING/FILENAME]
DESCRIPTION
-h Displays this help screen
-f Forces a check for network boundary when given a STRING(s)
-i Will read from an Input file (file should contain one CIDR per line) (no network boundary check)
-b Will do the same as –i but with network boundary check
EXAMPLES
./cidr-to-ip.sh 192.168.0.1/24
./cidr-to-ip.sh 192.168.0.1/24 10.10.0.0/28
./cidr-to-ip.sh -f 192.168.0.0/16
./cidr-to-ip.sh -i inputfile.txt
./cidr-to-ip.sh -b inputfile.txt
#!/bin/bash
############################
## Methods
############################
prefix_to_bit_netmask() {
prefix=$1;
shift=$(( 32 - prefix ));
bitmask=""
for (( i=0; i < 32; i++ )); do
num=0
if [ $i -lt $prefix ]; then
num=1
fi
space=
if [ $(( i % 8 )) -eq 0 ]; then
space=" ";
fi
bitmask="${bitmask}${space}${num}"
done
echo $bitmask
}
bit_netmask_to_wildcard_netmask() {
bitmask=$1;
wildcard_mask=
for octet in $bitmask; do
wildcard_mask="${wildcard_mask} $(( 255 - 2#$octet ))"
done
echo $wildcard_mask;
}
check_net_boundary() {
net=$1;
wildcard_mask=$2;
is_correct=1;
for (( i = 1; i <= 4; i++ )); do
net_octet=$(echo $net | cut -d '.' -f $i)
mask_octet=$(echo $wildcard_mask | cut -d ' ' -f $i)
if [ $mask_octet -gt 0 ]; then
if [ $(( $net_octet&$mask_octet )) -ne 0 ]; then
is_correct=0;
fi
fi
done
echo $is_correct;
}
#######################
## MAIN
#######################
OPTIND=1;
getopts "fibh" force;
shift $((OPTIND-1))
if [ $force = 'h' ]; then
echo ""
echo -e "THIS SCRIPT WILL EXPAND A CIDR ADDRESS.\n\nSYNOPSIS\n ./cidr-to-ip.sh [OPTION(only one)] [STRING/FILENAME]\nDESCRIPTION\n -h Displays this help screen\n -f Forces a check for network boundary when given a STRING(s)\n -i Will read from an Input file (no network boundary check)\n -b Will do the same as –i but with network boundary check\n\nEXAMPLES\n ./cidr-to-ip.sh 192.168.0.1/24\n ./cidr-to-ip.sh 192.168.0.1/24 10.10.0.0/28\n ./cidr-to-ip.sh -f 192.168.0.0/16\n ./cidr-to-ip.sh -i inputfile.txt\n ./cidr-to-ip.sh -b inputfile.txt\n"
exit
fi
if [ $force = 'i' ] || [ $force = 'b' ]; then
old_IPS=$IPS
IPS=$'\n'
lines=($(cat $1)) # array
IPS=$old_IPS
else
lines=$#
fi
for ip in ${lines[#]}; do
net=$(echo $ip | cut -d '/' -f 1);
prefix=$(echo $ip | cut -d '/' -f 2);
do_processing=1;
bit_netmask=$(prefix_to_bit_netmask $prefix);
wildcard_mask=$(bit_netmask_to_wildcard_netmask "$bit_netmask");
is_net_boundary=$(check_net_boundary $net "$wildcard_mask");
if [ $force = 'f' ] && [ $is_net_boundary -ne 1 ] || [ $force = 'b' ] && [ $is_net_boundary -ne 1 ] ; then
read -p "Not a network boundary! Continue anyway (y/N)? " -n 1 -r
echo ## move to a new line
if [[ $REPLY =~ ^[Yy]$ ]]; then
do_processing=1;
else
do_processing=0;
fi
fi
if [ $do_processing -eq 1 ]; then
str=
for (( i = 1; i <= 4; i++ )); do
range=$(echo $net | cut -d '.' -f $i)
mask_octet=$(echo $wildcard_mask | cut -d ' ' -f $i)
if [ $mask_octet -gt 0 ]; then
range="{$range..$(( $range | $mask_octet ))}";
fi
str="${str} $range"
done
ips=$(echo $str | sed "s, ,\\.,g"); ## replace spaces with periods, a join...
eval echo $ips | tr ' ' '\n'
else
exit
fi
done
nmap is useful, but an overkill.
You can use prips instead. Saves you the hassle of grepping out the extra output from nmap and using awk.
Calling prips 192.168.0.0/23 will print what you need.
I use the following to skip the network address and broadcast: prips "$subnet" | sed -e '1d; $d'
Prips also has other useful options, e.g. being able to sample every n-th IP.
It's available via apt,brew,rpm and as tar.gz.
This short script will print all the IP addresses in a CIDR range in a few lines of Bash. (I named it prips after the Ubuntu command of the same name. Obviously, if that command is available, use that.)
prips() {
local cidr="$1" ; local lo hi a b c d e f g h
# range is bounded by network (-n) & broadcast (-b) addresses.
lo="$(ipcalc -n "$cidr" | cut -f2 -d=)"
hi="$(ipcalc -b "$cidr" | cut -f2 -d=)"
IFS=. read -r a b c d <<< "$lo"
IFS=. read -r e f g h <<< "$hi"
eval "echo {$a..$e}.{$b..$f}.{$c..$g}.{$d..$h}"
}
Note that I assume the RedHat Linux (Erik Troan, Preston Brown) version of ipcalc, not the Krischan Jodies version that is installed on some platforms (e.g. Mac OS X).
Examples:
$ prips 10.0.0.128/27
10.0.0.128 10.0.0.129 10.0.0.130 10.0.0.131 10.0.0.132 10.0.0.133 10.0.0.134 10.0.0.135 10.0.0.136 10.0.0.137 10.0.0.138 10.0.0.139 10.0.0.140 10.0.0.141 10.0.0.142 10.0.0.143 10.0.0.144 10.0.0.145 10.0.0.146 10.0.0.147 10.0.0.148 10.0.0.149 10.0.0.150 10.0.0.151 10.0.0.152 10.0.0.153 10.0.0.154 10.0.0.155 10.0.0.156 10.0.0.157 10.0.0.158 10.0.0.159
Calculates correct number of addresses in a /23 networks:
$ prips 10.0.0.0/23 | wc -w
512
Inspecting a few of those addresses using cut:
$ prips 10.0.0.0/23 | cut -f1-10,256-266 -d' '
10.0.0.0 10.0.0.1 10.0.0.2 10.0.0.3 10.0.0.4 10.0.0.5 10.0.0.6 10.0.0.7 10.0.0.8 10.0.0.9 10.0.0.255 10.0.1.0 10.0.1.1 10.0.1.2 10.0.1.3 10.0.1.4 10.0.1.5 10.0.1.6 10.0.1.7 10.0.1.8 10.0.1.9
And maybe too slow but also correctly generates the 16 million addresses in a /8 network:
$ date ; prips 10.0.0.0/8 | wc -w ; date
Sat May 20 18:06:00 AEST 2017
16777216
Sat May 20 18:06:41 AEST 2017
I recently wrote a function to generate all IP addresses from a given network address. The function takes the network address as argument and accepts CIDR and subnet masks. The script then stores all IPs in the array variable $ips.
Code
network_address_to_ips() {
# create array containing network address and subnet
local network=(${1//\// })
# split network address by dot
local iparr=(${network[0]//./ })
# if no mask given it's the same as /32
local mask=32
[[ $((${#network[#]})) -gt 1 ]] && mask=${network[1]}
# convert dot-notation subnet mask or convert CIDR to an array like (255 255 255 0)
local maskarr
if [[ ${mask} =~ '.' ]]; then # already mask format like 255.255.255.0
maskarr=(${mask//./ })
else # assume CIDR like /24, convert to mask
if [[ $((mask)) -lt 8 ]]; then
maskarr=($((256-2**(8-mask))) 0 0 0)
elif [[ $((mask)) -lt 16 ]]; then
maskarr=(255 $((256-2**(16-mask))) 0 0)
elif [[ $((mask)) -lt 24 ]]; then
maskarr=(255 255 $((256-2**(24-mask))) 0)
elif [[ $((mask)) -lt 32 ]]; then
maskarr=(255 255 255 $((256-2**(32-mask))))
elif [[ ${mask} == 32 ]]; then
maskarr=(255 255 255 255)
fi
fi
# correct wrong subnet masks (e.g. 240.192.255.0 to 255.255.255.0)
[[ ${maskarr[2]} == 255 ]] && maskarr[1]=255
[[ ${maskarr[1]} == 255 ]] && maskarr[0]=255
# generate list of ip addresses
local bytes=(0 0 0 0)
for i in $(seq 0 $((255-maskarr[0]))); do
bytes[0]="$(( i+(iparr[0] & maskarr[0]) ))"
for j in $(seq 0 $((255-maskarr[1]))); do
bytes[1]="$(( j+(iparr[1] & maskarr[1]) ))"
for k in $(seq 0 $((255-maskarr[2]))); do
bytes[2]="$(( k+(iparr[2] & maskarr[2]) ))"
for l in $(seq 1 $((255-maskarr[3]))); do
bytes[3]="$(( l+(iparr[3] & maskarr[3]) ))"
printf "%d.%d.%d.%d\n" "${bytes[#]}"
done
done
done
done
}
Example
network_address_to_ips 10.0.1.0/255.255.255.240
network_address_to_ips 10.1.0.0/24
This script should do. It's (almost) pure Bash. The seq part can be replaced if a completely pure bash is required.
Since Bash apparently uses signed two-complement 4-byte integers, the script is limited to /8 mask maximum. I found ranges larger than /16 impractical anyway so this doesn't bother me at all. If someone knows a simple way to overcome this, please share :)
#!/usr/bin/env bash
BASE_IP=${1%/*}
IP_CIDR=${1#*/}
if [ ${IP_CIDR} -lt 8 ]; then
echo "Max range is /8."
exit
fi
IP_MASK=$((0xFFFFFFFF << (32 - ${IP_CIDR})))
IFS=. read a b c d <<<${BASE_IP}
ip=$((($b << 16) + ($c << 8) + $d))
ipstart=$((${ip} & ${IP_MASK}))
ipend=$(((${ipstart} | ~${IP_MASK}) & 0x7FFFFFFF))
seq ${ipstart} ${ipend} | while read i; do
echo $a.$((($i & 0xFF0000) >> 16)).$((($i & 0xFF00) >> 8)).$(($i & 0x00FF))
done
Usage:
./script.sh 192.168.13.55/22
Tested with Bash version 4.4.23. YMMV.
I think this little script I hacked together does the trick. If not, it's definitely a starting point! Good luck.
#!/bin/bash
############################
## Methods
############################
prefix_to_bit_netmask() {
prefix=$1;
shift=$(( 32 - prefix ));
bitmask=""
for (( i=0; i < 32; i++ )); do
num=0
if [ $i -lt $prefix ]; then
num=1
fi
space=
if [ $(( i % 8 )) -eq 0 ]; then
space=" ";
fi
bitmask="${bitmask}${space}${num}"
done
echo $bitmask
}
bit_netmask_to_wildcard_netmask() {
bitmask=$1;
wildcard_mask=
for octet in $bitmask; do
wildcard_mask="${wildcard_mask} $(( 255 - 2#$octet ))"
done
echo $wildcard_mask;
}
#######################
## MAIN
#######################
for ip in $#; do
net=$(echo $ip | cut -d '/' -f 1);
prefix=$(echo $ip | cut -d '/' -f 2);
bit_netmask=$(prefix_to_bit_netmask $prefix);
wildcard_mask=$(bit_netmask_to_wildcard_netmask "$bit_netmask");
str=
for (( i = 1; i <= 4; i++ )); do
range=$(echo $net | cut -d '.' -f $i)
mask_octet=$(echo $wildcard_mask | cut -d ' ' -f $i)
if [ $mask_octet -gt 0 ]; then
range="{0..$mask_octet}";
fi
str="${str} $range"
done
ips=$(echo $str | sed "s, ,\\.,g"); ## replace spaces with periods, a join...
eval echo $ips | tr ' ' '\012'
done
I have extended #rberg script a little.
check if the "network" you provide really is a network (use -f to skip the check)
handle netmasks greater than /24
Maybe this is of use for someone.
#!/bin/bash
############################
## Methods
############################
prefix_to_bit_netmask() {
prefix=$1;
shift=$(( 32 - prefix ));
bitmask=""
for (( i=0; i < 32; i++ )); do
num=0
if [ $i -lt $prefix ]; then
num=1
fi
space=
if [ $(( i % 8 )) -eq 0 ]; then
space=" ";
fi
bitmask="${bitmask}${space}${num}"
done
echo $bitmask
}
bit_netmask_to_wildcard_netmask() {
bitmask=$1;
wildcard_mask=
for octet in $bitmask; do
wildcard_mask="${wildcard_mask} $(( 255 - 2#$octet ))"
done
echo $wildcard_mask;
}
check_net_boundary() {
net=$1;
wildcard_mask=$2;
is_correct=1;
for (( i = 1; i <= 4; i++ )); do
net_octet=$(echo $net | cut -d '.' -f $i)
mask_octet=$(echo $wildcard_mask | cut -d ' ' -f $i)
if [ $mask_octet -gt 0 ]; then
if [ $(( $net_octet&$mask_octet )) -ne 0 ]; then
is_correct=0;
fi
fi
done
echo $is_correct;
}
#######################
## MAIN
#######################
OPTIND=1;
getopts "f" force;
shift $(( OPTIND-1 ));
for ip in $#; do
net=$(echo $ip | cut -d '/' -f 1);
prefix=$(echo $ip | cut -d '/' -f 2);
do_processing=1;
bit_netmask=$(prefix_to_bit_netmask $prefix);
wildcard_mask=$(bit_netmask_to_wildcard_netmask "$bit_netmask");
is_net_boundary=$(check_net_boundary $net "$wildcard_mask");
if [ $force != 'f' ] && [ $is_net_boundary -ne 1 ]; then
read -p "Not a network boundary! Continue anyway (y/N)? " -n 1 -r
echo ## move to a new line
if [[ $REPLY =~ ^[Yy]$ ]]; then
do_processing=1;
else
do_processing=0;
fi
fi
if [ $do_processing -eq 1 ]; then
str=
for (( i = 1; i <= 4; i++ )); do
range=$(echo $net | cut -d '.' -f $i)
mask_octet=$(echo $wildcard_mask | cut -d ' ' -f $i)
if [ $mask_octet -gt 0 ]; then
range="{$range..$(( $range | $mask_octet ))}";
fi
str="${str} $range"
done
ips=$(echo $str | sed "s, ,\\.,g"); ## replace spaces with periods, a join...
eval echo $ips | tr ' ' '\012'
fi
done
Wanted to comment on an answer above but don't have the rep yet.
Using the top solution with NMAP I added this to my .bashrc
expand-ip() {
nmap -sL -n -iL "$1" | awk '/Nmap scan report/{print $NF}'
}
Now I can use this with just expand-ip targs.
You can use this script (you need to have "bc" installed on your system):
for ip in $# ;do
net=$(echo $ip | cut -d '/' -f 1);
prefix=$(echo $ip | cut -d '/' -f 2);
o1=$(echo $net | cut -d '.' -f4);
o2=$(echo $net | cut -d '.' -f3);
o3=$(echo $net | cut -d '.' -f2);
o4=$(echo $net | cut -d '.' -f1);
len=$(echo "2^(32 - $prefix)"|bc);
for i in `seq $len`;do
echo "$o4.$o3.$o2.$o1";
o1=$(echo "$o1+1"|bc);
if [ $o1 -eq 256 ]; then
o1=0;
o2=$(echo "$o2+1"|bc);
if [ $o2 -eq 256 ]; then
o2=0;
o3=$(echo "$o3+1"|bc);
if [ $o3 -eq 256 ]; then
o3=0;
o4=$(echo "$o4+1"|bc);
fi
fi
fi
done
done
fping -Aaqgr 1 10.1.1.0/24
Simplicity works best
Related
In the first if we want the hostname to appear, which is the 5th field from a file. Then if the IP we give to the host command does not exist, then the command returns message 3 (NXDOMAIN). The script should recognize if the command was "not found". In this case it will
must simply print (-).
#!/bin/bash
ip="$1"
if [ "$ip" ] ; then
host "$ip" | cut -d' ' -f5
elif
[[ "$ip" =~ "[3(NXDOMAIN)]$" ]] ; then
echo "-"
fi
Do u have any solution on this exercise?
You're not testing the result of the host command, you're testing the value of the original $ip variable.
Save the output to a variable, test that variable, then either print the output or - depending on the test.
You don't need to do a regexp match, just match the exact string.
#!/bin/bash
ip="$1"
if [ "$ip" ] ; then
result=$(host "$ip" | cut -d" " -f5)
if [[ $result = "3(NXDOMAIN)" ]] ; then
echo "-"
else
echo "$result"
fi
fi
The answer is much simpler than you think, you don't need to do any matching. You can just use the return code from host
#!/bin/bash
ip="$1"
if domain=$(host "$1"); then
echo "${domain##* }"
else
echo "-"
fi
Proof of Concept
$ testHost(){ if domain=$(host "$1"); then echo "${domain##* }"; else echo "-"; fi }
$ testHost 172.217.6.46
sfo03s08-in-f14.1e100.net.
$ testHost 172.217.6.466
-
#!/bin/bash
if [ -n "$1" ] && [[ $1 =~ ^[[:digit:]]+\.[[:digit:]]+\.[[:digit:]]+\.[[:digit:]]+$ ]] ;then
res=$(host "$1" | cut -d' ' -f5)
if [ "$res" != "3(NXDOMAIN)" ]; then
echo "$res"
else
echo "-"
fi
else
echo "please enter a valid ip"
fi
if you want to cover also ipv6 then I think this will cover it
#!/bin/bash
# ipv4
if [[ $1 =~ ^([[:digit:]]{1,2}|1[[:digit:]][[:digit:]]|2[0-4][[:digit:]]|25[0-5])\.([[:digit:]]{1,2}|1[[:digit:]][[:digit:]]|2[0-4][[:digit:]]|25[0-5])\.([[:digit:]]{1,2}|1[[:digit:]][[:digit:]]|2[0-4][[:digit:]]|25[0-5])\.([[:digit:]]{1,2}|1[[:digit:]][[:digit:]]|2[0-4][[:digit:]]|25[0-5])$ ]]; then
res=`host "$1" | cut -d' ' -f5`
if [ "$res" != "3(NXDOMAIN)" ]; then
echo "$res"
else
# valid ipv4 IP but not connected
echo "-"
fi
# ipv6
elif [[ $1 =~ ^(([[:xdigit:]]{1,4}:){7,7}[[:xdigit:]]{1,4}|([[:xdigit:]]{1,4}:){1,7}:|([[:xdigit:]]{1,4}:){1,6}:[[:xdigit:]]{1,4}|([[:xdigit:]]{1,4}:){1,5}(:[[:xdigit:]]{1,4}){1,2}|([[:xdigit:]]{1,4}:){1,4}(:[[:xdigit:]]{1,4}){1,3}|([[:xdigit:]]{1,4}:){1,3}(:[[:xdigit:]]{1,4}){1,4}|([[:xdigit:]]{1,4}:){1,2}(:[[:xdigit:]]{1,4}){1,5}|[[:xdigit:]]{1,4}:((:[[:xdigit:]]{1,4}){1,6})|:((:[[:xdigit:]]{1,4}){1,7}|:)|fe80:(:[[:xdigit:]]{0,4}){0,4}%[0-9a-zA-Z]{1,}|::(ffff(:0{1,4}){0,1}:){0,1}((25[0-5]|(2[0-4]|1{0,1}[[:digit:]]){0,1}[[:digit:]])\.){3,3}(25[0-5]|(2[0-4]|1{0,1}[[:digit:]]){0,1}[[:digit:]])|([[:xdigit:]]{1,4}:){1,4}:((25[0-5]|(2[0-4]|1{0,1}[[:digit:]]){0,1}[[:digit:]])\.){3,3}(25[0-5]|(2[0-4]|1{0,1}[[:digit:]]){0,1}[[:digit:]]))$ ]]; then
res=`host "$1" | cut -d' ' -f5`
if [ "$res" != "3(NXDOMAIN)" ]; then
echo "1. $res"
else
# valid ipv6 IP but not connected
echo "2. -"
fi
else
echo "Please enter a valid IP"
fi
Note: For some versions of bash the -4 and -6 options do not work.
Thanks to Léa Gris for pointing out the locales problem.
Inspired from https://helloacm.com/how-to-valid-ipv6-addresses-using-bash-and-regex/
I want to input two and three digit numbers into a function and output a case range, i.e., input 33 and 66 and output 3[3-9] | [4-5][0-9] | 6[0-6] or input 33 and 666 and output 3[3-9] | [4-9][0-9] | [1-5][0-9][0-9] | 6[0-5][0-9] | 66[0-6]
What are some ideas as to how? Thanks!
Just want to share the final code: https://gist.github.com/zaydek/1627329f88c444f6d71d5cbc0cda616f :)
function enc {
a=${1: -3:1}; b=${1: -2:1}; c=${1: -1}
d=${2: -3:1}; e=${2: -2:1}; f=${2: -1}
if (( $[a] < $[d] )); then
if (( $b$c == 00 && $e$f == 99 )); then echo [$a-$d][0-9][0-9]
elif (( $b$c == 00 )); then if (( $[a+1] < $d )); then echo [$a-$[d-1]][0-9][0-9] "|"; echo $(enc $[d]00 $d$e$f)
else echo $a[0-9][0-9] "|"; echo $(enc $[a+1]00 $d$e$f); fi
else echo $(enc $a$b$c $[a]99) "|"; echo $(enc $[a+1]00 $d$e$f); fi
elif (( $b < $e )); then
if (( $c == 0 && $f == 9 )); then echo $a[$b-$e][0-9]
elif (( $c == 0 )); then if (( $[b+1] < $e )); then echo $a[$b-$[e-1]][0-9] "|"; echo $(enc $a$[e]0 $d$e$f)
else echo $a$b[0-9] "|"; echo $(enc $a$[e]0 $d$e$f); fi
else echo $(enc $a$b$c $a$[b]9) "|"; echo $(enc $a$[b+1]0 $d$e$f); fi
else
if (( $c == $f )); then echo $a$b$c
else echo $a$b[$c-$f]; fi; fi
}
function int {
if [[ $1 = *.* ]]; then
integer=${1%.*}
decimal=${1#*.}
if (( ${decimal:0:1} >= 5 )); then integer=$[integer+1]; fi
echo $integer
else echo $1; fi
}
function cse {
minimum=$(int $(echo $1 $2 | awk '{ print ($1/$2)*( 90) }'))
maximum=$(int $(echo $1 $2 | awk '{ print ($1/$2)*(110) }'))
echo $(enc $minimum $maximum)
}
cse $1 $2
cse takes two inputs, converts them to decimals, and multiples each from a range, i.e., 90 and 110 for -10% and +10% error range, then passes off the minimum and maximum outputs as inputs to enc which is a recursive function that generates case range syntax (with syntax optimization).
Please note, bash does not appear to handle expressions for case ranges as expected or intended. Though, this code can be used to generate case ranges for all 2 to 3 digit numbers and then copied and pasted as inline code.
Here is the max 2 digits case for 0-99, I'd not used character's operations indeed I'd tried math arithmetic.
The following are some output:
./range.sh 1 39 -> 0[1-9] | [1-2][0-9] | 3[0-9]
./range.sh 21 49 -> 2[1-9] | [3-4][0-9]
./range.sh 33 66 -> 3[3-9] | [4-5][0-9] | 6[0-6]
./range.sh 33 99 -> 3[3-9] | [4-8][0-9] | 9[0-9]
Here is my code: range.sh, hope it can provide some help for you:
#!/bin/bash
LHS=$1
RHS=$2
B2=10
D2=$(echo "($RHS-$LHS)/$B2" | bc)
if [[ ${D2} -gt 0 ]]; then
S2=(`seq $(echo "$LHS/$B2" | bc) $(echo "$LHS/$B2+$D2" | bc)`)
#echo ${S2[#]}
C=${#S2[#]}
#echo $C
L1=$(echo "$LHS%$B2" | bc)
if [[ ${L1} -lt 9 ]]; then
L1R="[${L1}-9]"
else
L1R="9"
fi
R1=$(echo "$RHS%$B2" | bc)
if [[ ${R1} -gt 0 ]]; then
R1R="[0-${R1}]"
else
R1R="[0-9]"
fi
if [[ ${C} -gt 3 ]]; then
echo -n $(echo "$LHS/$B2" | bc)$L1R
echo -n " | "[${S2[1]}-${S2[$C-2]}][0-9]
echo -n " | "${S2[$C-1]}$R1R
elif [[ ${C} -eq 3 ]]; then
if [[ ${S2[0]} -eq 0 ]]; then
echo -n 0$L1R
else
echo -n $(echo "$LHS/$B2" | bc)$L1R
fi
echo -n " | "[${S2[1]}-${S2[$C-1]}][0-9]
fi
else
echo [$LHS-$RHS]
fi
echo
Here is the logic for 2 digit numbers:
#!/bin/bash
l=$1
h=$2
function get_nearest_upper_10th_mutlitple()
{
v=$(($1+10))
echo "${v%?}0"
}
function get_nearest_lower_10th_mutlitple()
{
v=$1
echo "${v%?}0"
}
temp="$(printf '%d' $l | wc -m)$(printf '%d' $h | wc -m)"
case $temp in
11) echo "[$l-$h]" ;;
22|12)
a=$([[ $(($l%10)) -eq 0 ]] && echo $l || echo $(($(get_nearest_upper_10th_mutlitple $l)-1)))
if [[ $(printf '%d' $a | wc -m) -eq 1 ]]; then
echo [$l-$a]
else
[[ $a -gt $l ]] && echo "${l%?}[${l#?}-${a#?}]" || echo $a
fi
b=$([[ $(($h%10)) -eq 0 ]] && echo $h || get_nearest_lower_10th_mutlitple $h)
x=$((a+1))
y=$((b-1))
echo "[$(echo ${x%?}~${y%?} | sed 's/~/\n/g' | sort -n | uniq | paste -s -d '-')][${x#?}-${y#?}]"
[[ $b -lt $h ]] && echo "${h%?}[${b#?}-${h#?}]" || echo $b
esac
Here are sample outputs:
$ ./script.bash 2 8
[2-8]
$ ./script.bash 2 6
[2-6]
$ ./script.bash 2 68
[2-9]
[1-5][0-9]
6[0-8]
$ ./script.bash 23 68
2[3-9]
[3-5][0-9]
6[0-8]
$ ./script.bash 23 99
2[3-9]
[3-8][0-9]
9[0-9]
$ ./script.bash 23 80
2[3-9]
[3-7][0-9]
80
$ ./script.bash 40 80
40
[4-7][1-9]
80
$ ./script.bash 40 80 | paste -s -d '|'
40|[4-7][1-9]|80
$ ./script.bash 35 55
3[5-9]
[4][0-9]
5[0-5]
You can use paste -s -d '|' to combine the individual ranges into a single ORed range.
You can use the existing functions which I've made to extend it for 3 digit numbers (I'll post the 3 digit version too after some time with different cases for 13 and 12).
It is possible to write this script in another way to increment ip address whitout loops like this? Script, a port scanner, works fine and mine is only a question about efficiency. Sorry for my english and thanks for your answers.
#!/bin/bash
ip=$1
IFS=. read i1 i2 i3 i4 <<< "$ip"
port=$2
max=255
while [ $i1 -le $max ];do
while [ $i2 -le $max ]; do
while [ $i3 -le $max ]; do
while [ $i4 -le $max ]; do
timeout 0.4 bash -c "echo >/dev/tcp/$i1.$i2.$i3.$i4/$port" && echo "on $i1.$i2.$i3.$i4 port $port is open"
i4=$(($i4+1))
done
i4=0
i3=$(($i3+1))
done
i3=0
i2=$(($i2+1))
done
i2=0
i1=$(($i1+1))
done
This function just prints next ip:
nextip(){
IP=$1
IP_HEX=$(printf '%.2X%.2X%.2X%.2X\n' `echo $IP | sed -e 's/\./ /g'`)
NEXT_IP_HEX=$(printf %.8X `echo $(( 0x$IP_HEX + 1 ))`)
NEXT_IP=$(printf '%d.%d.%d.%d\n' `echo $NEXT_IP_HEX | sed -r 's/(..)/0x\1 /g'`)
echo "$NEXT_IP"
}
So you can increment it like:
FIRST_IP=192.168.1.250
NUM=10
IP=$FIRST_IP
for i in $(seq 1 $NUM); do
echo $IP
IP=$(nextip $IP)
done
Sample output:
192.168.1.250
192.168.1.251
192.168.1.252
192.168.1.253
192.168.1.254
192.168.1.255
192.168.2.0
192.168.2.1
192.168.2.2
192.168.2.3
Take a look at:
i1=0; i2=0; i3=0; i4=0
max=255
eval printf -v ip "%s\ " {$i1..$max}.{$i2..$max}.{$i3..$max}.{$i4..$max}
for i in $ip; do
# do here somthing with $i
done
I'm trying to imitate the bash file completion.
Suppose I have the following files:
test1
test2
With an input string of "te" I would like to get the output "test"
This is my current attempt ($c is the input string):
l=1
q="$c"
for j in $(ls -A | grep "^$c"); do
if [ "${j/$c}" != "$j" ]; then
n=$(ls -A | grep ^$j | wc -l)
if [ $n -gt $l ]; then
q="$j"
fi
fi
done
c="$q"
echo $c
Thanks for any help
I tend to think there is no a way to get this from completion engine since it’s not a part of GNU Bash but Readline. But at least we can get list of possible completions with compgen. And an inmplementaion of finding longest common prefix should not be problem. So...
#!/bin/bash
SCRIPTNAME="${0##*/}"
USAGE="Usage: $SCRIPTNAME <prefix>
Print common prefix of possible file name completions. Like <TAB> but to
stdout."
(( $# == 1 )) || { printf >&2 '%s\n' "$USAGE"; exit 1; }
PREFIX="$1"
commonprefix() {
(( $# >= 2 )) || {
echo "$1"
return 0
}
local -i i N M
for ((i=0; i<=${#1}; i++)); do
for ((N=1; N<=$#-1; N++)); do
let M=$N+1
[[ ${!N:i:1} == ${!M:i:1} ]] || break 2
done
done
echo "${1:0:i}"
}
readarray -t COMPLETIONS < <(compgen -f "$PREFIX")
commonprefix "${COMPLETIONS[#]}"
Although Dmitry Alexandrov already provided a better solution, I still would like to post my own one which I made while waiting for the answers:
l=1
while [ -n $l ]; do
l=${#c}
a=$(ls -A | grep "^$c" | wc -l)
q=$c
for i in $(ls -A | grep "^$q"); do
if [ $i == $q ]; then
unset l
break
else
v=$(ls -A | grep "^$q${i:$l:1}" | wc -l)
if [ $v == $a ]; then
q="$c${i:$l:1}"
break
fi
fi
done
if [ $c == $q ]; then break; fi
c=$q
done
echo $c
It works with all of my tests, but it's slow (although it could be optimized).
Just to show that you were thinking in correct direction, I made your code work:
#!/bin/bash
c=$1
q="$c"
for j in $c*; do
if [ "${j/$c}" != "$j" ]; then
startn=$(ls -1A | grep -c "^${j:0:$((${#c} + 1))}")
for (( i=${#c}; i <= ${#j}; i++ )); do
n=$(ls -1A | grep -c "^${j:0:$i}")
if [ "$n" -lt "$startn" ]; then
q="${j:0:$((i - 1))}"
elif [ "$n" -le "$startn" ]; then
q="${j:0:$i}"
fi
done
fi
done
c="$q"
echo "$c"
But, it's just a proof of concept, don't use it. See answer by Dmitry Alexandrov for a good solution.
I am receiving numeric variables sometimes with 2, other times with 3 digits, like '321' and '32'. And I want to put a dot among each of the numbers. So if I receive '32', I got to echo '3.2' and if I receive '321' I echo '3.2.1'.
This is what I did:
S='321'
SL="${#S}" #string lentgh
n1=`echo $S | cut -c 1-1`
n2=`echo $S | cut -c 2-2`
if [ "$SL" -eq 2 ]; then
echo $n1.$n2
elif [ "$SL" -eq 3 ]; then
n3=`echo $S | cut -c 3-3`
echo $n1.$n2.$n3
else
die 'Works only with 2 or 3 digits'
fi
My question is: is there any shorter way of doing the same thing?
UPDATE:
Shorter but still verbose:
SL="${#1}" #string lentgh
S=$1
if [ "$1" -eq 3 ]; then
$n3=".${S:2:1}"
fi
if [ "$SL" -lt 2 ] && [ "$SL" -gt 3 ]; then
die 'Works only with 2 or 3 digits'
fi
echo "${S:0:1}.${S:1:1}$n3"
UPDATE 1:
If I include the if block, the sed+regex version will be quite as long as the pure bash version:
SL="${#1}" #string lentgh
S=$1
N=$(echo $S | sed -r "s/([0-9])/\1./g")
echo ${N%%.}
if [ "$SL" -lt 2 ] && [ "$SL" -gt 3 ]; then
die 'Works only with 2 or 3 digits'
fi
Or, using a one line sed+regex with two expressions:
SL="${#1}" #string lentgh
echo $1 | sed -e 's/\([[:digit:]]\)/.\1/g' -e 's/^\.//'
if [ "$SL" -lt 2 ] && [ "$SL" -gt 3 ]; then
die 'Works only with 2 or 3 digits'
fi
Thanks.
I prefer also the sed for that:
echo 321 | sed -e 's/\([[:digit:]]\)/.\1/g' | cut -b2- -> 3.2.1
echo 32 | sed -e 's/\([[:digit:]]\)/.\1/g' | cut -b2- -> 3.2
Or without cut it looks like this
echo 321 | sed -e 's/\([[:digit:]]\)/.\1/g' -e 's/^\.//'
Here is one. This will work for any string length.
#!/bin/bash
#s is the string
#fs is the final string
echo "Enter string"
read s
n="${#s}"
fs=""
i=0
for ((i=0; i<n; i++))
do
fs="$fs.${s:i:1}"
done
#find the length of the final string and
#remove the leading '.'
n="${#fs}"
fs="${fs:1}"
echo "$fs"
It's not that pretty, but at least it's short:
num=$(echo $S | sed -r "s/([0-9])/\1./g")
echo ${num%%.}
S='321'
perl -e "print join '.', split //, shift" "$S"