批量SSH key-gen无密码登陆认证脚本

使用为了让linux之间使用ssh不需要密码，可以采用了数字签名RSA或者DSA来完成。主要使用ssh-key-gen实现。

1.通过 ssh-key-gen 来创建 public and private keys

2.使用ssh-copy-id复制public key 到远程主机

3.无密码登陆远程主机

但对于大规模集群，人工使用ssh-key-gen生成key，再使用ssh-copy-id显然费时费力。对于N台主机，需要进行N次ssh-key-gen，N*N次ssh-copy-id。

为此，写了一个批量SSH key-gen脚本，脚本包括四个文件：keygen_master.sh、keygen_slave.sh、hosts.conf、slaves.conf

项目参见https://github.com/Beckham007/b_keygen

使用方法比较简单。把这四个文件拷贝到主节点上，设置hosts.conf和slaves.conf，然后执行keygen_master.sh即可。

keygen_master.sh在主节点上执行。

#!/bin/sh
this="$0"
while [ -h "$this" ]; do
  ls=`ls -ld "$this"`
  link=`expr "$ls" : '.*-> \(.*\)$'`
  if expr "$link" : '.*/.*' > /dev/null; then
    this="$link"
else
    this=`dirname "$this"`/"$link"
  fi
done

# init base path
base=`dirname "$this"`
script=`basename "$this"`
base=`cd "$base"; pwd`
this="$base/$script"
slavesh="keygen_slave.sh"
slavescript="$base/$slavesh"
slaves="$base/slaves.conf"
hosts="$base/hosts.conf"

# install ssh
yum install -y openssh* expect

eval `ssh-agent`

if [ ! -s ~/.ssh/id_dsa ]; then
  expect -c "
  spawn ssh-keygen -t dsa
    expect {
      \"*y/n*\" {send \"y\r\"; exp_continue}
      \"*key*\" {send \"\r\"; exp_continue}
      \"*passphrase*\" {send \"\r\"; exp_continue}
      \"*again*\" {send \"\r\";}
    }
  "
fi

ssh-add $HOME/.ssh/id_dsa # Add private key

# batch ssh   
if [ -s $hosts ]; then
  for p in $(cat $hosts)  # 
  do
    username=$(echo "$p"|cut -f1 -d":") # Get username 
    ip=$(echo "$p"|cut -f2 -d":")       # Get ip  
    password=$(echo "$p"|cut -f3 -d":") # Get password 
    id=$HOME/.ssh/id_dsa.pub

    echo "ssh-copy-id -i $id  $username@$ip -P $password"
    # ssh-copy-id
    expect -c "
    spawn ssh-copy-id -i $id  $username@$ip
      expect {
        \"*yes/no*\" {send \"yes\r\"; exp_continue}
        \"*password*\" {send \"$password\r\"; exp_continue}
        \"*Password*\" {send \"$password\r\";}
      }
    "
  done
fi

# dispath   
if [ -s $slaves ]; then
  for p in $(cat $slaves)  # 
  do
    username=$(echo "$p"|cut -f1 -d":") # Get username 
    ip=$(echo "$p"|cut -f2 -d":")       # Get ip  
    password=$(echo "$p"|cut -f3 -d":") # Get password 
    id=$HOME/.ssh/id_dsa.pub

    ssh $username@$ip 'yum install -y openssh*'
    
    echo "scp $slavescript $hosts $username@$ip:~/ -P $password"
    # Dispath to clients
    expect -c "
    spawn scp $slavescript $hosts $username@$ip:~/
      expect {
        \"*yes/no*\" {send \"yes\r\"; exp_continue}
        \"*password*\" {send \"$password\r\"; exp_continue}
        \"*Password*\" {send \"$password\r\";}
      }
    "

    # ssh to clients
    echo "ssh $username@$ip 'sh $HOME/keygen_slave.sh'"
    ssh $username@$ip 'sh $HOME/keygen_slave.sh'
  done
fi

keygen_slave.sh在所有从节点执行。

#!/bin/sh
this="$0"
while [ -h "$this" ]; do
  ls=`ls -ld "$this"`
  link=`expr "$ls" : '.*-> \(.*\)$'`
  if expr "$link" : '.*/.*' > /dev/null; then
    this="$link"
else
    this=`dirname "$this"`/"$link"
  fi
done

# init base path
base=`dirname "$this"`
script=`basename "$this"`
base=`cd "$base"; pwd`
this="$base/$script"
hosts="$base/hosts.conf"

echo $base
echo $script
echo $this
echo $hosts

# install ssh
yum install -y openssh* expect

eval `ssh-agent`

if [ ! -s ~/.ssh/id_dsa ]; then
  expect -c "
  spawn ssh-keygen -t dsa
    expect {
      \"*y/n*\" {send \"y\r\"; exp_continue}
      \"*key*\" {send \"\r\"; exp_continue}
      \"*passphrase*\" {send \"\r\"; exp_continue}
      \"*again*\" {send \"\r\";}
    }
  "
fi

ssh-add $HOME/.ssh/id_dsa # Add private key

# batch ssh   
if [ -s $hosts ]; then
  for p in $(cat $hosts)  # 
  do
    username=$(echo "$p"|cut -f1 -d":") # Get username 
    ip=$(echo "$p"|cut -f2 -d":")       # Get ip  
    password=$(echo "$p"|cut -f3 -d":") # Get password 
    id=$HOME/.ssh/id_dsa.pub

    echo $username
    echo $ip
    echo $password
    echo $id

    # ssh-copy-id    
    expect -c "
    spawn ssh-copy-id -i $id  $username@$ip
      expect {
        \"*yes/no*\" {send \"yes\r\"; exp_continue}
        \"*password*\" {send \"$password\r\"; exp_continue}
        \"*Password*\" {send \"$password\r\";}
      }
    "
  done
fi

hosts.conf中设置所有主机（主节点+从节点），格式为用户名:主机IP:用户密码。

username:master_ip:passwd
username:client1_ip:passwd
username:client2_ip:passwd

#root:localhost:000000

slaves.conf中设置所有从主机，格式同hosts.conf用户名:主机IP:用户密码。

username:client1_ip:passwd
username:client2_ip:passwd

#root:192.168.1.12:000000

下载地址https://github.com/Beckham007/b_keygen/archive/master.zip

以上脚本在天翼云主机 CentOS 6.4 64位上测试成功。