SSH登录的预期步骤 [英] Expect Procedure for SSH Login
问题描述
我是Expect脚本的新手.我正在尝试创建一个程序，该程序将通过SSH连接到路由器/交换机，并在失败时回退至telnet.在将其放入过程之前，我拥有的代码可以正常工作.我确定我对程序的工作方式不了解.当我将其作为过程调用时，它确实通过SSH进行连接，该SSH收到连接被拒绝"并按预期方式回退至telnet，但它从未使用密码登录.当我启用调试模式时，我看到它发送了密码，但是由于某种原因，路由器似乎并没有收到它.它只是位于密码:"提示下，直到超时为止.
I'm new to Expect scripting. I'm trying to create a procedure that will connect to routers/switches over SSH and fall back to telnet if that fails. The code that I have works fine before I put it inside a procedure. I'm sure there's something I'm not understanding about how procedures work. When I call it as a procedure it does connect via SSH which receives "Connection refused" and falls back to telnet like it is supposed to, it just never logs in with the password. When I enable debug mode I see it sends the password but for some reason the router doesn't seem like it receives it. It just sits at the Password: prompt until it times out.
proc connectToTerminal { username hostname password } {
# Run ssh, don't display key warning
spawn ssh -o StrictHostKeyChecking=no $username\@$hostname
# Allow this script to handle ssh connection issues, fall back to telnet
expect {
timeout { send_user "\nTimeout Exceeded - Check Host\n"; exit 1 }
eof { send_user "\nSSH Connection To $hostname Failed\n"; exit 1 }
# If we have the correct prompt, continue
"*#" {}
# If it's asking for the password, it can have it
"*assword:" { send "$password\n" }
# Fall back to telnet if connection refused
"Connection refused" {
spawn telnet $hostname
#expect "username:"
#send "$username\n"
expect "*assword:"
send "$password\n"
}
# Fall back to telnet if connection is closed by [ip address]
-re {closed by \d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}} {
spawn telnet $hostname
#expect "username:"
#send "$username\n"
expect "*assword:"
send "$password\n"
}
# Use SSH v1 if the device is only accepting v1
"2 vs. 1" {
spawn ssh -1 -o StrictHostKeyChecking=no $username\@$hostname
expect {
"*assword:" { send "$password\n" }
timeout {
spawn telnet $hostname
#expect "username:"
#send "$username\n"
expect "*assword:"
send "$password\n"
}
}
}
}
}
connectToTerminal $username $hostname $password
下面是我运行脚本时的调试输出
Below is the debug output when I run the script
spawn ssh -o StrictHostKeyChecking=no wmh@172.16.1.195
parent: waiting for sync byte
parent: telling child to go ahead
parent: now unsynchronized from child
spawn: returns {7726}
Gate keeper glob pattern for 'closed by \d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}' is 'closed by *'. Activating booster.
expect: does "" (spawn_id exp6) match glob pattern "*#"? no
"*assword:"? no
"Connection refused"? no
"closed by \d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}"? Gate "closed by *"? gate=no
"2 vs. 1"? no
ssh: connect to host 172.16.1.195 port 22: Connection refused
expect: does "ssh: connect to host 172.16.1.195 port 22: Connection refused\r\r\n" (spawn_id exp6) match glob pattern "*#"? no
"*assword:"? no
"Connection refused"? yes
expect: set expect_out(0,string) "Connection refused"
expect: set expect_out(spawn_id) "exp6"
expect: set expect_out(buffer) "ssh: connect to host 172.16.1.195 port 22: Connection refused"
spawn telnet 172.16.1.195
parent: waiting for sync byte
parent: telling child to go ahead
parent: now unsynchronized from child
spawn: returns {7730}
expect: does "" (spawn_id exp7) match glob pattern "*assword:"? no
Trying 172.16.1.195...
expect: does "Trying 172.16.1.195...\r\n" (spawn_id exp7) match glob pattern "*assword:"? no
Connected to 172.16.1.195.
expect: does "Trying 172.16.1.195...\r\nConnected to 172.16.1.195." (spawn_id exp7) match glob pattern "*assword:"? no
expect: does "Trying 172.16.1.195...\r\nConnected to 172.16.1.195.\r\n" (spawn_id exp7) match glob pattern "*assword:"? no
Escape character is '^]'.
expect: does "Trying 172.16.1.195...\r\nConnected to 172.16.1.195.\r\nEscape character is '^]'." (spawn_id exp7) match glob pattern "*assword:"? no
expect: does "Trying 172.16.1.195...\r\nConnected to 172.16.1.195.\r\nEscape character is '^]'.\r\n" (spawn_id exp7) match glob pattern "*assword:"? no
C
*********************************************************************
* *
* *
* *
* THIS COMPUTER IS FOR PRIVATE USE ONLY *
* ------------------------------------- *
* *
* UNAUTHORIZED access to and/or use of this computer syst
expect: does "Trying 172.16.1.195...\r\nConnected to 172.16.1.195.\r\nEscape character is '^]'.\r\nC\r\n*********************************************************************\r\n* *\r\n* *\r\n* *\r\n* THIS COMPUTER IS FOR PRIVATE USE ONLY *\r\n* ------------------------------------- *\r\n* *\r\n* UNAUTHORIZED access to and/or use of this computer syst" (spawn_id exp7) match glob pattern "*assword:"? no
em *
* is a violation of law and is punishable under provisions of *
* 19 USC 1029 and 18 USC 1030, and applicable statutes. Use *
* of this system constitutes consent to security testing and *
* monitoring. *
* *
* 11-12-13 *
*********************************************************************
User Access Verification
Password:
expect: does "Trying 172.16.1.195...\r\nConnected to 172.16.1.195.\r\nEscape character is '^]'.\r\nC\r\n*********************************************************************\r\n* *\r\n* *\r\n* *\r\n* THIS COMPUTER IS FOR PRIVATE USE ONLY *\r\n* ------------------------------------- *\r\n* *\r\n* UNAUTHORIZED access to and/or use of this computer system *\r\n* is a violation of law and is punishable under provisions of *\r\n* 19 USC 1029 and 18 USC 1030, and applicable statutes. Use *\r\n* of this system constitutes consent to security testing and *\r\n* monitoring. *\r\n* *\r\n* 11-12-13 *\r\n*********************************************************************\r\n\r\n\r\nUser Access Verification\r\n\r\nPassword: " (spawn_id exp7) match glob pattern "*assword:"? yes
expect: set expect_out(0,string) "Trying 172.16.1.195...\r\nConnected to 172.16.1.195.\r\nEscape character is '^]'.\r\nC\r\n*********************************************************************\r\n* *\r\n* *\r\n* *\r\n* THIS COMPUTER IS FOR PRIVATE USE ONLY *\r\n* ------------------------------------- *\r\n* *\r\n* UNAUTHORIZED access to and/or use of this computer system *\r\n* is a violation of law and is punishable under provisions of *\r\n* 19 USC 1029 and 18 USC 1030, and applicable statutes. Use *\r\n* of this system constitutes consent to security testing and *\r\n* monitoring. *\r\n* *\r\n* 11-12-13 *\r\n*********************************************************************\r\n\r\n\r\nUser Access Verification\r\n\r\nPassword:"
expect: set expect_out(spawn_id) "exp7"
expect: set expect_out(buffer) "Trying 172.16.1.195...\r\nConnected to 172.16.1.195.\r\nEscape character is '^]'.\r\nC\r\n*********************************************************************\r\n* *\r\n* *\r\n* *\r\n* THIS COMPUTER IS FOR PRIVATE USE ONLY *\r\n* ------------------------------------- *\r\n* *\r\n* UNAUTHORIZED access to and/or use of this computer system *\r\n* is a violation of law and is punishable under provisions of *\r\n* 19 USC 1029 and 18 USC 1030, and applicable statutes. Use *\r\n* of this system constitutes consent to security testing and *\r\n* monitoring. *\r\n* *\r\n* 11-12-13 *\r\n*********************************************************************\r\n\r\n\r\nUser Access Verification\r\n\r\nPassword:"
send: sending "cisco\n" to { exp7 }
expect: does "" (spawn_id exp0) match glob pattern "*#"? no
"*>"? no
expect: timed out
推荐答案
发送密码后，只需再添加一个expect语句即可.
After sending the password, just add one more expect statement.
set prompt "#"
send "$password \r"
expect "$prompt"
除非我们明确告知Expect等待它，否则会话中不会有任何期望.
Unless we explicitly tell Expect to wait for it, it won't expect anything from the session.
更新:
我不确定您是否错过了expect语句或在调用程序中未正确放置它.如果仍然无法解决，请更新您的问题.
I'm not sure if you have missed the expect statement or misplaced it in the caller procedure. Update your issues if still not solved.
如果将expect语句放置在另一个proc中，则应将spawn_id传递给它，以便Expect可以正确等待它.否则，如果spawn_id为空，则将恢复默认行为.也就是说，它应该来自stdin.
If you have placed the expect statement in another proc, then the spawn_id should be passed on to it, so that Expect can wait for it properly. Else, the default behavior will be restored if spawn_id is empty. i.e. it will expect from the stdin.
从您的调试输出中可以明显地看到
It is evident from your debug output
expect: does "" (spawn_id exp0) match glob pattern "*#"? no
其中exp0除了stdin外什么都没有.在该过程内部，生成telnet之后，可以将spawn_id保存到另一个变量中，并将其返回到可以使用它的调用者过程.
where exp0 is nothing but the stdin. Inside that procedure, after spawning the telnet , you can save the spawn_id in to another variable and return it to caller procedure where it can be used.
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