GO中的SCP信宿实现

Question

我正在尝试在GO中实现SSH服务器，它充当SCP接收器(无需调用外部scp命令(
我最终得到了部分工作代码：https://gist.github.com/Seitanas/ad02158e8d5d2acedd9e7973ae44c77c.问题是，当我尝试将文件scp到此服务时，本地scp客户端正确复制数据，但返回1。
我认为通道关闭时发生了一些事情。也许我在SCP协议中遗漏了什么？我猜ssh返回-1，然后scp以1退出测试结果：

echo "contents"> test.txt
scp -v -P2222 test.txt foo@127.0.0.1:/
Executing: program /usr/bin/ssh host 127.0.0.1, user foo, command scp -v -t /
...
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: password
debug1: Next authentication method: password
foo@127.0.0.1's password:
debug1: Authentication succeeded (password).
Authenticated to 127.0.0.1 ([127.0.0.1]:2222).
debug1: channel 0: new [client-session]
debug1: Requesting [e-mail]
debug1: Entering interactive session.
debug1: pledge: network
debug1: Sending environment.
debug1: Sending env LC_TERMINAL_VERSION = 3.4.12
debug1: Sending env LC_CTYPE = en_US.UTF-8
debug1: Sending env LC_TERMINAL = iTerm2
debug1: Sending command: scp -v -t /
Sending file modes: C0644 9 test.txt
test.txt                                                                                                                                                                                                    0%    0     0.0KB/s   --:-- ETAdebug1: channel 0: free: client-session, nchannels 1
test.txt                                                                                                                                                                                                  100%    9    21.4KB/s   00:00
debug1: fd 0 clearing O_NONBLOCK
Transferred: sent 2032, received 1116 bytes, in 0.0 seconds
Bytes per second: sent 1245098.0, received 683823.5
debug1: Exit status -1
echo $?
1

go代码输出：

go run test.go
2022/02/15 17:17:21 Command: C
2022/02/15 17:17:21 File info: 0644 9 test.txt
2022/02/15 17:17:21 File size: 9
2022/02/15 17:17:21 Content: contents

谢谢你的意见。

Answer 1

好的，我发现了问题所在。我忘了我在模拟SCP二进制蚂蚁服务器端，所以我也需要模拟它的退出代码。所以我在末尾添加了一行：

channel.SendRequest("exit-status", false, []byte{0, 0, 0, 0})

这将通过通道发送exit 0状态。如果没有它，客户端的SCP正在等待远程传输完成，但套接字在传输后立即关闭，没有退出代码。

现在一切如预期：

debug1: Sending command: scp -v -t /
Sending file modes: C0644 9 test.txt
test.txt                                                                                                                                                                                                    0%    0     0.0KB/s   --:-- ETAdebug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug1: channel 0: free: client-session, nchannels 1
test.txt                                                                                                                                                                                                  100%    9    14.1KB/s   00:00
debug1: fd 0 clearing O_NONBLOCK
Transferred: sent 2152, received 1172 bytes, in 0.0 seconds
Bytes per second: sent 1391979.3, received 758085.4
debug1: Exit status 0