Criar alias para conexão ssh

Question

Gostaria de acelerar a conexão a servidores específicos.

Eu tenho os servidores, digamos:

123.123.123.1
123.123.123.2
123.123.123.3

Eu normalmente me conecto com o seguinte:

ssh -p 12345 [email protected]

Isso é uma dor, porque a única diferença entre os servidores é o último número do ip.

Eu tentei o seguinte código:

alias ssht='{ ip=$(cat -); ssh -p 12345 my_user@"123.123.123.$ip"; }<<<'

No entanto, recebo um erro:

karl@karls-laptop ~/scripts $ ssht 1
Pseudo-terminal will not be allocated because stdin is not a terminal.

Existe uma maneira de fazer isso funcionar?

    

Answer 1

Isso exige uma função - simples e robusta, enquanto um alias nesse caso seria frágil.

Algo como isso deve ser feito:

function ssht () {
    [[  =~ ^(1|2|3)$ ]] || { echo 'Not a valid last octet value !!' && return ;}
    ip=123.123.123.
    ssh my_user@"$ip" -p 12345
}

A condição [[ =~ ^(1|2|3)$ ]] garante que você tenha inserido 1, 2, 3 como primeiro argumento (qualquer argumento posterior será ignorado).

Agora, você pode dar o último octeto desejado como o primeiro argumento:

ssht 1
ssht 2
ssht 3

Coloque isso no seu ~/.bashrc para disponibilizá-lo em qualquer sessão interativa.

    

Answer 2

Use o caminho pretendido e escreva as opções e aliases em ~/.ssh/config :

Host 1
  Port 12345
  User my_user
  HostName 123.123.123.1

Host 2
  Port 12345
  User my_user
  HostName 123.123.123.2

e assim por diante ...

E, em seguida, conecte apenas usando

ssh 1
ssh 2
...

    

Answer 3

Você pode usar padrões em ~/.ssh/config . De man ssh_config :

PATTERNS
     A pattern consists of zero or more non-whitespace characters, ‘*’ (a
     wildcard that matches zero or more characters), or ‘?’ (a wildcard that
     matches exactly one character).  For example, to specify a set of
     declarations for any host in the “.co.uk” set of domains, the following
     pattern could be used:

           Host *.co.uk

     The following pattern would match any host in the 192.168.0.[0-9] network
     range:

           Host 192.168.0.?

Combinado com:

HostName
    Specifies the real host name to log into.  This can be used to
    specify nicknames or abbreviations for hosts.  If the hostname
    contains the character sequence ‘%h’, then this will be replaced
    with the host name specified on the command line (this is useful
    for manipulating unqualified names).  The character sequence ‘%%’
    will be replaced by a single ‘%’ character, which may be used
    when specifying IPv6 link-local addresses.

Então, no seu ~/.ssh/config , coloque:

Host ?
    Hostname 123.123.123.%h
    Port 12345
    User my_user

Então:

$ ssh -v 1
OpenSSH_7.4p1, LibreSSL 2.5.0
debug1: Reading configuration data /home/muru/.ssh/config
debug1: /home/muru/.ssh/config line 41: Applying options for ?
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Connecting to 123.123.123.1 [123.123.123.1] port 12345.
debug1: connect to address 123.123.123.1 port 12345: Connection refused
ssh: connect to host 123.123.123.1 port 12345: Connection refused

    

Answer 4

Use uma função:

function ssht(){
 ssh -p 12345 [email protected].
}

$ ssht 1
$ ssht 2
$ ...

Uma solução melhor é usar um arquivo ssh config :

touch ~/.ssh/config

com algumas linhas semelhantes a:

Host some-name
    HostName 123.123.123.1
    User your_user
    Port 22

Você também pode usar as teclas ssh para melhorar a velocidade; finalmente, você só executa:

ssh some-name

e você está conectado a esse servidor.

    

O

Answer 5

Você nem precisa usar um nome como ssht. Nomes começando com dígitos, mesmo apenas dígitos são nomes de host válidos no arquivo de configuração ssh.

Abaixo, funciona no Xubuntu Xenial

Parte do meu ~ / .ssh / config

Host 1
        Hostname bastion.example.me
        User said
        Port 22
        IdentityFile ~/.ssh/id_rsa
        ForwardAgent yes

Comando que eu executo (abaixo eu adicionei -vv para log detalhado a STDOUT a.k.a sua tela por padrão)

ssh -vv 1

Saída

OpenSSH_7.2p2 Ubuntu-4ubuntu2.2, OpenSSL 1.0.2g  1 Mar 2016
debug1: Reading configuration data /home/said/.ssh/config
debug1: /home/said/.ssh/config line 24: Applying options for 1
debug1: /home/said/.ssh/config line 540: Applying options for *
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug2: resolving "bastion.example.me" port 22
debug2: ssh_connect_direct: needpriv 0
debug1: Connecting to bastion.example.me [XXX.YYY.120.51] port 22.
debug1: Connection established.
debug1: identity file /home/said/.ssh/id_rsa type 1
debug1: key_load_public: No such file or directory
debug1: identity file /home/said/.ssh/id_rsa-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_7.2p2 Ubuntu-4ubuntu2.2
debug1: Remote protocol version 2.0, remote software version OpenSSH_7.2p2 Ubuntu-4ubuntu2.2
debug1: match: OpenSSH_7.2p2 Ubuntu-4ubuntu2.2 pat OpenSSH* compat 0x04000000
debug2: fd 3 setting O_NONBLOCK
debug1: Authenticating to bastion.example.me:22 as 'said'
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug2: local client KEXINIT proposal
debug2: KEX algorithms: [email protected],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,ext-info-c
debug2: host key algorithms: [email protected],[email protected],[email protected],ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,[email protected],[email protected],ssh-ed25519,rsa-sha2-512,rsa-sha2-256,ssh-rsa
debug2: ciphers ctos: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected],aes128-cbc,aes192-cbc,aes256-cbc,3des-cbc
debug2: ciphers stoc: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected],aes128-cbc,aes192-cbc,aes256-cbc,3des-cbc
debug2: MACs ctos: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: MACs stoc: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: compression ctos: none,[email protected],zlib
debug2: compression stoc: none,[email protected],zlib
debug2: languages ctos: 
debug2: languages stoc: 
debug2: first_kex_follows 0 
debug2: reserved 0 
debug2: peer server KEXINIT proposal
debug2: KEX algorithms: [email protected],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha1
debug2: host key algorithms: ssh-rsa,rsa-sha2-512,rsa-sha2-256,ecdsa-sha2-nistp256,ssh-ed25519
debug2: ciphers ctos: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected]
debug2: ciphers stoc: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected]
debug2: MACs ctos: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: MACs stoc: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: compression ctos: none,[email protected]
debug2: compression stoc: none,[email protected]
debug2: languages ctos: 
debug2: languages stoc: 
debug2: first_kex_follows 0 
debug2: reserved 0 
debug1: kex: algorithm: [email protected]
debug1: kex: host key algorithm: ecdsa-sha2-nistp256
debug1: kex: server->client cipher: [email protected] MAC: <implicit> compression: none
debug1: kex: client->server cipher: [email protected] MAC: <implicit> compression: none
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: ecdsa-sha2-nistp256 SHA256:44tChrTUMwuRcOi6laiYlf6VM3qAD+PEn9EdNMribFw
debug1: Host 'bastion.example.me' is known and matches the ECDSA host key.
debug1: Found key in /home/said/.ssh/known_hosts:69
debug2: set_newkeys: mode 1
debug1: rekey after 134217728 blocks
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug2: set_newkeys: mode 0
debug1: rekey after 134217728 blocks
debug1: SSH2_MSG_NEWKEYS received
debug2: key: /home/said/.ssh/id_rsa (0x562c764294f0), explicit, agent
debug1: SSH2_MSG_EXT_INFO received
debug1: kex_input_ext_info: server-sig-algs=<rsa-sha2-256,rsa-sha2-512>
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey
debug1: Next authentication method: publickey
debug1: Offering RSA public key: /home/said/.ssh/id_rsa
debug2: we sent a publickey packet, wait for reply
debug1: Server accepts key: pkalg rsa-sha2-512 blen 279
debug2: input_userauth_pk_ok: fp SHA256:KQNLYiJICyNbKmIxVVgc67RF+qRKjNi3w+0iXz/YDyk
debug1: Authentication succeeded (publickey).
Authenticated to bastion.example.me ([XXX.YYY.120.51]:22).
debug1: channel 0: new [client-session]
debug2: channel 0: send open
debug1: Requesting [email protected]
debug1: Entering interactive session.
debug1: pledge: network
debug1: client_input_global_request: rtype [email protected] want_reply 0
debug2: callback start
debug1: Requesting authentication agent forwarding.
debug2: channel 0: request [email protected] confirm 0
debug2: fd 3 setting TCP_NODELAY
debug2: client_session2_setup: id 0
debug2: channel 0: request pty-req confirm 1
debug2: channel 0: request shell confirm 1
debug2: callback done
debug2: channel 0: open confirm rwindow 0 rmax 32768
debug2: channel_input_status_confirm: type 99 id 0
debug2: PTY allocation request accepted on channel 0
debug2: channel 0: rcvd adjust 2097152
debug2: channel_input_status_confirm: type 99 id 0
debug2: shell request accepted on channel 0
Welcome to Ubuntu 16.04.2 LTS (GNU/Linux 4.8.0-42-lowlatency x86_64)
<TRUNCATED CUSTOM MOTD>
$

Atualização - abaixo está uma solução alternativa hackeada, leve-a apenas para exercícios basistas, talvez para coisas rápidas e sujas:

alias ssht='f(){ ssh -p 22 [email protected].$@;unset -f f;}&&f'

O que faz

• Criar função temporária
• Passar todos os argumentos para ele
• Faça a conexão SSH
• Quando a sessão terminar, desative a função para que ela não fique por perto
• Pode levar argumentos adicionais, o que significa que você pode acoplar opções adicionais de ssh como tunelamento ( -L , -R , -D ), modo detalhado ( -vv ), não-TTY ( -T ) etc.

Por exemplo, quero iniciar um proxy de meias sem terminal

$ ssht 2 -vv -D 1080 -T
OpenSSH_7.2p2 Ubuntu-4ubuntu2.2, OpenSSL 1.0.2g  1 Mar 2016
debug1: Reading configuration data /home/said/.ssh/config
debug1: /home/said/.ssh/config line 540: Applying options for *
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug2: resolving "192.168.0.2" port 22
debug2: ssh_connect_direct: needpriv 0
debug1: Connecting to 192.168.0.2 [192.168.0.2] port 22.
debug1: Connection established.
<TRUNCATED>
Welcome to Linux Mint 18.1 Serena (GNU/Linux 4.4.0-81-generic x86_64)

 * Documentation:  https://www.linuxmint.com

98 packages can be updated.
0 updates are security updates.

Como você pode ver, nenhum prompt de comando foi executado com -vv , -T , -D 1080 arguments.

Eu posso verificar o túnel (basicamente o proxy SOCKS5) na minha máquina, também

$ ss -ltnp | grep 1080
LISTEN     0      128    127.0.0.1:1080                     *:*                   users:(("ssh",pid=17038,fd=6))