血的教训--kail系统免密centos7的坑【高版本ssh免密低版本ssh的坑】

血的教训–kail系统免密centos7的坑【高版本ssh免密低版本ssh的坑】

最近下载了一个2023版本的kail系统，但是经过几次设置免密后，ssh过去一直让提供密码，所以就仔细的分析了一下，果然还是发现了点猫腻

接上一个博客，大家可以看看，ssh免密之间的坑
入侵redis之准备—linux之间的免密通信原来是这么的简单

ssh免密其实很简单，但是没想到还是有一些坑
出现免密失败的情况，我也是百度了好多，都是让更改目录的权限，但是都失败了，其实这跟权限有关系，但是我们基本上也不会动这些目录的权限，如果你的权限没有问题，那就可以往我这个方向考虑了，那就是高版本的ssh加密方式和低版本ssh啊hi见的加密方式不一样，大家知道最近ssh低于9版本有漏洞，所以ssh版本都升级到9以上了，但是部分还是9一下版本，这个就是免密失败的原因。

关键报错：

debug2: we did not send a packet, disable method
debug3: authmethod_lookup publickey
debug3: remaining preferred: keyboard-interactive,password
debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey
debug1: Trying private key: /home/liushuai/.ssh/id_rsa
debug3: no such identity: /home/liushuai/.ssh/id_rsa: No such file or directory
debug1: Trying private key: /home/liushuai/.ssh/id_ecdsa
debug3: no such identity: /home/liushuai/.ssh/id_ecdsa: No such file or directory
debug1: Trying private key: /home/liushuai/.ssh/id_ecdsa_sk
debug3: no such identity: /home/liushuai/.ssh/id_ecdsa_sk: No such file or directory
debug1: Trying private key: /home/liushuai/.ssh/id_ed25519
debug3: no such identity: /home/liushuai/.ssh/id_ed25519: No such file or directory
debug1: Trying private key: /home/liushuai/.ssh/id_ed25519_sk
debug3: no such identity: /home/liushuai/.ssh/id_ed25519_sk: No such file or directory
debug1: Trying private key: /home/liushuai/.ssh/id_xmss
debug3: no such identity: /home/liushuai/.ssh/id_xmss: No such file or directory
debug2: we did not send a packet, disable method
debug3: authmethod_lookup password
debug3: remaining preferred: ,password
debug3: authmethod_is_enabled password
debug1: Next authentication method: password

其他文章：

入侵redis并实现反弹shell控制【实战一】

• 学习大概步骤如下
• 第一步:先学习怎么安装部署kail系统服务器
  入侵redis之准备—VMware安装部署kail镜像服务器【详细包含云盘镜像】
• 第二步：再学习怎么安装部署centos系统服务器
  入侵redis之准备—VMware上面安装部署centos7镜像系统【详细含云盘镜像】
• 再学习下linux下面的定时任务crontab相关知识打下基础
  入侵redis之准备—Linux关于定时任务crontab相关知识了解配合理解shell反弹远程控制
• 再学习下centos7上面部署redis，毕竟咱们还是要入侵他的哈
  入侵redis之准备—Centos7上面部署redis
• 再学习下如何使用python来破解下redis的密码
  血的教训------入侵redis之利用python来破解redis密码
• 最后就是我们精彩的入侵redis并远程控制你的机器复现
  血的教训—入侵redis并远程控制你的机器场景复现

入侵redis并实现免密登录服务器【实战二】

• 学习大概步骤如下
• 第一步:先学习怎么安装部署kail系统服务器
  入侵redis之准备—VMware安装部署kail镜像服务器【详细包含云盘镜像】
• 第二步：再学习怎么安装部署centos系统服务器
  入侵redis之准备—VMware上面安装部署centos7镜像系统【详细含云盘镜像】
• 再学习下linux之间的免密通信原来是这么的简单
  入侵redis之准备—linux之间的免密通信原来是这么的简单
• 再学习下ssh免密登录的一些坑，ssh高版本免密低版本的坑
  血的教训–kail系统免密centos7的坑【高版本ssh免密低版本ssh的坑】
• 再学习下centos7上面部署redis，毕竟咱们还是要入侵他的哈
  入侵redis之准备—Centos7上面部署redis
• 再学习下如何使用python来破解下redis的密码
  血的教训------入侵redis之利用python来破解redis密码
• 最后就是我们精彩的入侵redis并免密登录redis所在服务器
  血的教训—入侵redis并免密登录redis所在服务器

废话不多说，直接开干

系统	ip	介绍
kail系统	192.168.126.132	生成公钥，并推送到centos7上
centos7	192.168.126.133	接受免密，实现kail往centos7方向免密

先按照老的免密方式搞一波

生成密钥

┌──(liushuai㉿bogon)-[~]
└─$ ssh-keygen -t dsa   ###注意看，咱这边的加密方式是dsa，这个就是坑
Generating public/private dsa key pair.
Enter file in which to save the key (/home/liushuai/.ssh/id_dsa): 
Created directory '/home/liushuai/.ssh'.
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in /home/liushuai/.ssh/id_dsa
Your public key has been saved in /home/liushuai/.ssh/id_dsa.pub
The key fingerprint is:
SHA256:k47VhY43db0GBtwHoUvZIVgnPDYui3QtT4vsGgBXewQ liushuai@bogon
The key's randomart image is:
+---[DSA 1024]----+
|       E..==.=o  |
|      . o. BO..o |
|   . . . .=+=+o .|
|    o  ..O.*o.. .|
|     .. S %..  o |
|      .= * +  .  |
|      ..o        |
|        ..       |
|       ..        |
+----[SHA256]-----+

拷贝密钥

┌──(liushuai㉿bogon)-[~]
└─$ ssh-copy-id root@192.168.196.133
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/home/liushuai/.ssh/id_dsa.pub"
The authenticity of host '192.168.196.133 (192.168.196.133)' can't be established.
ED25519 key fingerprint is SHA256:ieG7iUYRDYyuZcBk5f2ABb9S2us0LzsIZEJqzhQwdFM.
This key is not known by any other names.
Are you sure you want to continue connecting (yes/no/[fingerprint])? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@192.168.196.133's password: Number of key(s) added: 1Now try logging into the machine, with:   "ssh 'root@192.168.196.133'"
and check to make sure that only the key(s) you wanted were added.

测试免密登录

┌──(liushuai㉿bogon)-[~]
└─$ ssh root@192.168.196.133        
root@192.168.196.133's password:             ####还是需要密码的，为什么的接着往下看

原因分析

经过排查，是因为两台主机的ssh版本问题

kail系统的版本：OpenSSH_9.3p2 Debian-1

┌──(liushuai㉿bogon)-[~]
└─$ ssh -V                                                     
OpenSSH_9.3p2 Debian-1, OpenSSL 3.0.10 1 Aug 2023

centos的版本：7.4P1

进一步分析

利用ssh -vvv的功能，查看问题出现在哪里

                                                                             
┌──(liushuai㉿bogon)-[~]
└─$ ssh root@192.168.196.133
root@192.168.196.133's password: 
Last login: Wed Nov 29 07:52:35 2023
[root@bogon ~]# exit
logout
Connection to 192.168.196.133 closed.┌──(liushuai㉿bogon)-[~]
└─$ ssh root@192.168.196.133 -vvv
OpenSSH_9.3p2 Debian-1, OpenSSL 3.0.10 1 Aug 2023
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: include /etc/ssh/ssh_config.d/*.conf matched no files
debug1: /etc/ssh/ssh_config line 21: Applying options for *
debug2: resolve_canonicalize: hostname 192.168.196.133 is address
debug3: expanded UserKnownHostsFile '~/.ssh/known_hosts' -> '/home/liushuai/.ssh/known_hosts'
debug3: expanded UserKnownHostsFile '~/.ssh/known_hosts2' -> '/home/liushuai/.ssh/known_hosts2'
debug3: ssh_connect_direct: entering
debug1: Connecting to 192.168.196.133 [192.168.196.133] port 22.
debug3: set_sock_tos: set socket 3 IP_TOS 0x10
debug1: Connection established.
debug1: identity file /home/liushuai/.ssh/id_rsa type -1
debug1: identity file /home/liushuai/.ssh/id_rsa-cert type -1
debug1: identity file /home/liushuai/.ssh/id_ecdsa type -1
debug1: identity file /home/liushuai/.ssh/id_ecdsa-cert type -1
debug1: identity file /home/liushuai/.ssh/id_ecdsa_sk type -1
debug1: identity file /home/liushuai/.ssh/id_ecdsa_sk-cert type -1
debug1: identity file /home/liushuai/.ssh/id_ed25519 type -1
debug1: identity file /home/liushuai/.ssh/id_ed25519-cert type -1
debug1: identity file /home/liushuai/.ssh/id_ed25519_sk type -1
debug1: identity file /home/liushuai/.ssh/id_ed25519_sk-cert type -1
debug1: identity file /home/liushuai/.ssh/id_xmss type -1
debug1: identity file /home/liushuai/.ssh/id_xmss-cert type -1
debug1: identity file /home/liushuai/.ssh/id_dsa type 1
debug1: identity file /home/liushuai/.ssh/id_dsa-cert type -1
debug1: Local version string SSH-2.0-OpenSSH_9.3p2 Debian-1
debug1: Remote protocol version 2.0, remote software version OpenSSH_7.4
debug1: compat_banner: match: OpenSSH_7.4 pat OpenSSH_7.4* compat 0x04000006
debug2: fd 3 setting O_NONBLOCK
debug1: Authenticating to 192.168.196.133:22 as 'root'
debug3: record_hostkey: found key type ED25519 in file /home/liushuai/.ssh/known_hosts:1
debug3: record_hostkey: found key type ECDSA in file /home/liushuai/.ssh/known_hosts:2
debug3: load_hostkeys_file: loaded 2 keys from 192.168.196.133
debug1: load_hostkeys: fopen /home/liushuai/.ssh/known_hosts2: No such file or directory
debug1: load_hostkeys: fopen /etc/ssh/ssh_known_hosts: No such file or directory
debug1: load_hostkeys: fopen /etc/ssh/ssh_known_hosts2: No such file or directory
debug3: order_hostkeyalgs: have matching best-preference key type [e-mail], using HostkeyAlgorithms verbatim
debug3: send packet: type 20
debug1: SSH2_MSG_KEXINIT sent
debug3: receive packet: type 20
debug1: SSH2_MSG_KEXINIT received
debug2: local client KEXINIT proposal
debug2: KEX algorithms: [e-mail],curve25519-sha256,[e-mail],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,diffie-hellman-group14-sha256,ext-info-c
debug2: host key algorithms: [e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],ssh-ed25519,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,[e-mail],[e-mail],rsa-sha2-512,rsa-sha2-256
debug2: ciphers ctos: [e-mail],aes128-ctr,aes192-ctr,aes256-ctr,[e-mail],[e-mail]
debug2: ciphers stoc: [e-mail],aes128-ctr,aes192-ctr,aes256-ctr,[e-mail],[e-mail]
debug2: MACs ctos: [e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: MACs stoc: [e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: compression ctos: none,[e-mail],zlib
debug2: compression stoc: none,[e-mail],zlib
debug2: languages ctos: 
debug2: languages stoc: 
debug2: first_kex_follows 0 
debug2: reserved 0 
debug2: peer server KEXINIT proposal
debug2: KEX algorithms: curve25519-sha256,[e-mail],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha256,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: host key algorithms: ssh-rsa,rsa-sha2-512,rsa-sha2-256,ecdsa-sha2-nistp256,ssh-ed25519
debug2: ciphers ctos: [e-mail],aes128-ctr,aes192-ctr,aes256-ctr,[e-mail],[e-mail],aes128-cbc,aes192-cbc,aes256-cbc,blowfish-cbc,cast128-cbc,3des-cbc
debug2: ciphers stoc: [e-mail],aes128-ctr,aes192-ctr,aes256-ctr,[e-mail],[e-mail],aes128-cbc,aes192-cbc,aes256-cbc,blowfish-cbc,cast128-cbc,3des-cbc
debug2: MACs ctos: [e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: MACs stoc: [e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: compression ctos: none,[e-mail]
debug2: compression stoc: none,[e-mail]
debug2: languages ctos: 
debug2: languages stoc: 
debug2: first_kex_follows 0 
debug2: reserved 0 
debug1: kex: algorithm: curve25519-sha256
debug1: kex: host key algorithm: ssh-ed25519
debug1: kex: server->client cipher: [e-mail] MAC: <implicit> compression: none
debug1: kex: client->server cipher: [e-mail] MAC: <implicit> compression: none
debug3: send packet: type 30
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug3: receive packet: type 31
debug1: SSH2_MSG_KEX_ECDH_REPLY received
debug1: Server host key: ssh-ed25519 SHA256:ieG7iUYRDYyuZcBk5f2ABb9S2us0LzsIZEJqzhQwdFM
debug3: record_hostkey: found key type ED25519 in file /home/liushuai/.ssh/known_hosts:1
debug3: record_hostkey: found key type ECDSA in file /home/liushuai/.ssh/known_hosts:2
debug3: load_hostkeys_file: loaded 2 keys from 192.168.196.133
debug1: load_hostkeys: fopen /home/liushuai/.ssh/known_hosts2: No such file or directory
debug1: load_hostkeys: fopen /etc/ssh/ssh_known_hosts: No such file or directory
debug1: load_hostkeys: fopen /etc/ssh/ssh_known_hosts2: No such file or directory
debug1: Host '192.168.196.133' is known and matches the ED25519 host key.
debug1: Found key in /home/liushuai/.ssh/known_hosts:1
debug3: send packet: type 21
debug2: ssh_set_newkeys: mode 1
debug1: rekey out after 134217728 blocks
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug3: receive packet: type 21
debug1: SSH2_MSG_NEWKEYS received
debug2: ssh_set_newkeys: mode 0
debug1: rekey in after 134217728 blocks
debug3: ssh_get_authentication_socket_path: path '/tmp/ssh-6WK2JhuI1VHD/agent.1125'
debug1: get_agent_identities: bound agent to hostkey
debug1: get_agent_identities: ssh_fetch_identitylist: agent contains no identities
debug1: Skipping ssh-dss key /home/liushuai/.ssh/id_dsa - corresponding algo not in PubkeyAcceptedAlgorithms
debug1: Will attempt key: /home/liushuai/.ssh/id_rsa 
debug1: Will attempt key: /home/liushuai/.ssh/id_ecdsa 
debug1: Will attempt key: /home/liushuai/.ssh/id_ecdsa_sk 
debug1: Will attempt key: /home/liushuai/.ssh/id_ed25519 
debug1: Will attempt key: /home/liushuai/.ssh/id_ed25519_sk 
debug1: Will attempt key: /home/liushuai/.ssh/id_xmss 
debug2: pubkey_prepare: done
debug3: send packet: type 5
debug3: receive packet: type 7
debug1: SSH2_MSG_EXT_INFO received
debug1: kex_input_ext_info: server-sig-algs=<rsa-sha2-256,rsa-sha2-512>
debug3: receive packet: type 6
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug3: send packet: type 50
debug3: receive packet: type 51
debug1: Authentications that can continue: publickey,gssapi-keyex,gssapi-with-mic,password
debug3: start over, passed a different list publickey,gssapi-keyex,gssapi-with-mic,password
debug3: preferred gssapi-with-mic,publickey,keyboard-interactive,password
debug3: authmethod_lookup gssapi-with-mic
debug3: remaining preferred: publickey,keyboard-interactive,password
debug3: authmethod_is_enabled gssapi-with-mic
debug1: Next authentication method: gssapi-with-mic
debug1: No credentials were supplied, or the credentials were unavailable or inaccessible
No Kerberos credentials available (default cache: FILE:/tmp/krb5cc_1000)debug1: No credentials were supplied, or the credentials were unavailable or inaccessible
No Kerberos credentials available (default cache: FILE:/tmp/krb5cc_1000)debug1: Unspecified GSS failure.  Minor code may provide more information
No such file or directorydebug2: we did not send a packet, disable method
debug3: authmethod_lookup publickey
debug3: remaining preferred: keyboard-interactive,password
debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey
debug1: Trying private key: /home/liushuai/.ssh/id_rsa   ###出现找不到文件
debug3: no such identity: /home/liushuai/.ssh/id_rsa: No such file or directory
debug1: Trying private key: /home/liushuai/.ssh/id_ecdsa  ###出现找不到文件
debug3: no such identity: /home/liushuai/.ssh/id_ecdsa: No such file or directory
debug1: Trying private key: /home/liushuai/.ssh/id_ecdsa_sk  ###出现找不到文件
debug3: no such identity: /home/liushuai/.ssh/id_ecdsa_sk: No such file or directory
debug1: Trying private key: /home/liushuai/.ssh/id_ed25519  ###出现找不到文件
debug3: no such identity: /home/liushuai/.ssh/id_ed25519: No such file or directory
debug1: Trying private key: /home/liushuai/.ssh/id_ed25519_sk  ###出现找不到文件
debug3: no such identity: /home/liushuai/.ssh/id_ed25519_sk: No such file or directory
debug1: Trying private key: /home/liushuai/.ssh/id_xmss  ###出现找不到文件
debug3: no such identity: /home/liushuai/.ssh/id_xmss: No such file or directory
debug2: we did not send a packet, disable method
debug3: authmethod_lookup password
debug3: remaining preferred: ,password
debug3: authmethod_is_enabled password
debug1: Next authentication method: password
root@192.168.196.133's password: 

更改加密方式为rsa

清理掉之前的密钥文件

──(liushuai㉿bogon)-[~]
└─$ cd .ssh ┌──(liushuai㉿bogon)-[~/.ssh]
└─$ ls    
id_dsa  id_dsa.pub  known_hosts  known_hosts.old┌──(liushuai㉿bogon)-[~/.ssh]   ###直接在.ssh目录下，清理即可，如有需要建议备份
└─$ rm -rf *
zsh: sure you want to delete all 4 files in /home/liushuai/.ssh [yn]? y┌──(liushuai㉿bogon)-[~/.ssh]
└─$ ls

### 重新生成密钥

┌──(liushuai㉿bogon)-[~/.ssh]
└─$ ssh-keygen -t rsa              ##更换了加密算法为rsa 
Generating public/private rsa key pair.
Enter file in which to save the key (/home/liushuai/.ssh/id_rsa): 
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in /home/liushuai/.ssh/id_rsa
Your public key has been saved in /home/liushuai/.ssh/id_rsa.pub
The key fingerprint is:
SHA256:VvO9A4ARor8FdlPJ2n6mpUy0ZOp3jRQpaitbqKTGTRI liushuai@bogon
The key's randomart image is:
+---[RSA 3072]----+
|      . oo..     |
|     . . +o      |
|    . o +o+  .   |
|  E  o o.o*+o.   |
|   .  . SB oo..  |
|  . .  =+ + =. . |
| . +. oo.+ B oo  |
|  oo....o = o .. |
| .. . .o . .     |
+----[SHA256]-----+

推送密钥

──(liushuai㉿bogon)-[~/.ssh]
└─$ ssh-copy-id root@192.168.196.133   ###推送方式不变
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/home/liushuai/.ssh/id_rsa.pub"
The authenticity of host '192.168.196.133 (192.168.196.133)' can't be established.
ED25519 key fingerprint is SHA256:ieG7iUYRDYyuZcBk5f2ABb9S2us0LzsIZEJqzhQwdFM.
This key is not known by any other names.
Are you sure you want to continue connecting (yes/no/[fingerprint])? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@192.168.196.133's password: Number of key(s) added: 1Now try logging into the machine, with:   "ssh 'root@192.168.196.133'"
and check to make sure that only the key(s) you wanted were added.

测试免密效果

└─$ ssh root@192.168.196.133                                   
Last login: Wed Nov 29 07:58:29 2023 from 192.168.196.132
[root@bogon ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00inet 127.0.0.1/8 scope host lovalid_lft forever preferred_lft foreverinet6 ::1/128 scope host valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000link/ether 00:0c:29:96:4f:10 brd ff:ff:ff:ff:ff:ffinet 192.168.196.133/24 brd 192.168.196.255 scope global noprefixroute dynamic ens33valid_lft 1416sec preferred_lft 1416secinet6 fe80::bbeb:becc:8125:c52f/64 scope link noprefixroute valid_lft forever preferred_lft forever
[root@bogon ~]# exit
logout                                                                                                                                                                                                     
Connection to 192.168.196.133 closed.

结束语

没有随随便便的成功，只有不断的努力