Curl

SNI header

curl -k -I 
curl --connect-to www.example.com:443:example.a:443 https://www.example.com
curl -sv   --resolve $host:443:$ip https://$host
curl --resolve example.com:443:127.0.0.1 https://example.com/
curl -vik --resolve example.com:443:198.18.110.10 https://example.com/

curl.exe --connect-to api.example.com:443:myapp.azurewebsites.net https://api.example.com/mypath/health

curl.exe -w "%{time_total}" --connect-to api.example.com:443:myapp.azurewebsites.net https://api.example.com/mypath/health

 tshark -l -i F5_Internal -f 'dst port ( 443 )' -Y 'ssl.handshake.extension.type == "server_name" || http.host' -T fields -e ip.src -e ip.dst -e tcp.dstport -e ssl.handshake.extensions_server_name -e http.host | grep example

Non sni header (port 80 unencrypted header)

curl --header "Host: example.com" http://127.0.0.1/

https://daniel.haxx.se/blog/2018/04/05/curl-another-host/

Testing ciphers

# curl https://www.example.com -k -v --location-trusted --sslv2
curl https://www.example.com -k -v --location-trusted --tlsv1.1
curl https://www.example.com -k -v --location-trusted --tlsv1.2
curl https://www.example.com -k -v --location-trusted --tlsv1.3

for host in 10.1.1.10 10.1.1.52 10.1.1.16 10.1.1.16; do echo $host; curl --header "Host: www.example.org" http://$host/downloads/myfile.png --output /dev/null; done

SNI Spoofing for HTTPS

https://everything.curl.dev/usingcurl/connections/name

https://daniel.haxx.se/blog/2018/04/05/curl-another-host/

BASH Wrapper

#!/usr/bin/env bash

if [[ "$#" -lt 3 ]]; then
  echo "Usage: $0 <type> <curl metric> <url>"
  echo "Example: $0 url time_connect https://google.com"
echo "
====URL Type Metrics====
time_namelookup
time_connect
time_appconnec
time_pretransfer
time_redirect
time_starttransfer
time_total
"
  exit
fi
curltype=$1
metric=$2
url=$3

if [[ "$curltype" == "url" ]]; then
  cmd="/usr/bin/curl -w \" %{$metric}\" -o /dev/null -s \"$url\""
  metric_value=$(eval "$cmd")
elif [[ "$curltype" == "resolve" ]]; then
  if [[ "$#" -lt 4 ]]; then
    echo "Usage: $0 <type> <curl metric> <url> <spoof ipaddr>"
    echo "Example: $0 resolve time_total https://example.org 127.0.0.1"
    exit
  fi
   ipaddr=$4
   host=$(echo "$url" | awk -F/ '{print $3}')
   cmd="/usr/bin/curl -w \"%{time_total}\" -o /dev/null -s --resolve $host:443:$ipaddr \"$url\""
   metric_value=$(eval "$cmd")
elif [[ "$curltype" == "connect-to" ]]; then
  if [[ "$#" -lt 4 ]]; then
    echo "Usage: $0 <type> <curl metric> <url> <fqdn>"
    echo "Example: $0 connect-to time_total https://example.org myapp-svc.azurewebsites.net"
    exit
  fi
   dstadc_fqdn=$4
   host=$(echo "$url" | awk -F/ '{print $3}')
   cmd="/usr/bin/curl -w \"%{time_total}\" -o /dev/null -s --resolve $host:443:$dstadc_fqdn \"$url\""
   metric_value=$(eval "$cmd")
else
  echo "E: Unsupported type of check."
fi

code=$?
if [[ "$code" != 0 ]]; then
   # echo error
    echo "$metric_value"
else
    echo "$metric_value"
fi

load generator using curl

#!/usr/bin/env bash
set -eu
# max_time=.1
max_time=2
# --connect-timeout
# connection_timeout=1
load_url(){
  url=$1
  adc=$2
  text=$3
  count=$4
  host=$(echo "$url" | awk -F/ '{print $3}')

  a=()
  for i in $(seq $count); do
    curl -m $max_time -s --resolve $host:443:$adc $url | grep -i $text > /dev/null
    if [[ $? == 0 ]]; then
       a+=(0)
    else
       a+=(1)
    fi
    echo $a
  done
}

count=5
url="https://example.com/path/health"
adc="myapp.azurewebsites.net"
text="Healthy"
r=$(load_url $url $adc $text $count)
echo $r

adc="lb.example.com"
r=$(load_url $url $adc $text $count)
echo $r


# for value in "${a[@]}"; do
#   echo $value
# done

Parallel

xargs -I % -P 5 curl -I "https://linuxways.net" < <(printf '%s\n' {1..10})
seq 1 10 | xargs -I % -P 5 curl -I "https://linuxways.net"
xargs -P 5 -n 1 curl -O < download.txt



xargs -I % -P 8 curl -X POST --header "http://localhost:5000/example" \
< <(printf '%s\n' {1..400})
This will run give curl command 400 times with max 8 jobs in parallel.

https://linuxhint.com/execute-multiple-curl-requests-parallel/ https://stackoverflow.com/questions/46362284/run-multiple-curl-commands-in-parallel

#!/bin/bash
set -eu
if [[ "$#" -lt 7 ]]; then
  echo "Usage: $0 <action> <entry-host> <url> <count> <tcount> <env> <text>"
  echo "Example: $0 load1 appservice.azurewebsites.net  https://www.example.com/path/health 1 5 dev Healthy"
  exit
fi
  action=$1
  entry_host=$2
  url=$3
  count=$4
  tcount=$5
  env=$6
  text=$7
  host=$(echo "$url" | awk -F/ '{print $3}')
  # echo $env

  a=()
get_url(){
  action=$1
  entry_host=$2
  url=$3
  count=$4
  tcount=$5
  env=$6
  text=$7
  host=$8
  if [[ "$env" == "dev" ]]; then
    env_abrv="d"; append=".dev"  #dev
  elif [[ $env == "prod" ]]; then
    env_abrv="p"; append=""  # prod
  else
    echo E: invalid env!
  fi
  r=$(curl -s --resolve $host:443:$entry_host $url | grep $text > /dev/null || echo 1)
  echo -n "$r "
}


load1(){
  export -f get_url
  start_time=$(date +%s%N)
  # seq $tcount  | xargs -n 1 -P $count -I {} bash -c "get_url $1"
  seq $tcount  | xargs -n 1 -P $count -I {} bash -c "get_url $action $entry_host $url $count $tcount $env $text $host"
  end_time=$(date +%s%N)
  diff_nanoseconds=$((end_time-start_time))
  # diff_seconds=$(($diff_nanoseconds / 1000000000))
  diff_seconds=$(bc <<< "scale=3; $diff_nanoseconds / 1000000000")
  echo ""
  echo seconds:$diff_seconds
}

load1