c++ - LibSSH C++ 包装器 - 离开范围时的基本远程连接段错误

Question

我是 libssh 的新手，正在尝试连接到远程机器以运行一些命令。所有的连接和命令都没有错误地返回，但是程序在离开作用域时会出现段错误。我究竟做错了什么？

代码

#include <string>
#include <iostream>
using namespace std;

#define SSH_NO_CPP_EXCEPTIONS
#include <libssh/libsshpp.hpp>

int main()
{
    ssh::Session session;

    //Set options
    session.setOption(SSH_OPTIONS_HOST, "192.168.200.101");
    session.setOption( SSH_OPTIONS_USER, "user" );

    //Connect to host
    session.connect();

    //Authenticate user
    session.userauthPassword( "password" );

    //Open channel
    ssh::Channel channel( session );
    channel.openSession();

    //Do something
    channel.requestExec( "ps_aux" );

    //Close channel
    channel.sendEof();
    channel.close();

    //Disconnect
    session.disconnect();

    return 0;
}

GDB 跟踪

Program received signal SIGSEGV, Segmentation fault.
0x00007ffff3a70a2f in ssh_channel_free () from /usr/local/lib/libssh.so.4
(gdb) where
#0  0x00007ffff3a70a2f in ssh_channel_free () from /usr/local/lib/libssh.so.4
#1  0x000000000059f436 in ssh::Channel::~Channel() ()
#2  0x000000000059e603 in main ()

Answer 1

经过一段时间的努力，我们有了一个可行的解决方案。第一个障碍是识别远程主机必须是“已知主机”。之后，对我来说，有必要在运行我的可执行文件之前获取环境。最后，我需要给它一些时间来处理 sleep( 1 )。享受吧。

#include <iostream>
using namespace std;

#include <libssh/libsshpp.hpp>

int main()
{
    int port = 22;

    //Can use SSH_LOG_PROTOCOL here for verbose output
    int verbosity = SSH_LOG_NOLOG;

    ssh::Session session;

    try
    {
        session.setOption( SSH_OPTIONS_LOG_VERBOSITY, &verbosity );
        session.setOption( SSH_OPTIONS_PORT, &port );
        session.setOption( SSH_OPTIONS_USER, "user" );
        session.setOption( SSH_OPTIONS_HOST, "192.168.52.101" );

        session.connect();

        if( session.isServerKnown() != SSH_SERVER_KNOWN_OK )
        {
            if( session.writeKnownhost() != SSH_OK )
            {
                cout << "writeKnownHost failed" << endl;
            }
            else
            {
                session.connect();
            }
        }

        if( session.userauthPassword( "password" ) != SSH_AUTH_SUCCESS )
        {
            cout << "failed auth" << endl;
        }

        ssh::Channel channel( session );
        channel.openSession();
        //Source environment if necessary, run executable
        channel.requestExec( "source /path/to/set_env.sh; /path/to/executable/..." );
        channel.close();
        channel.sendEof();

        //Unfortunate brute force step, the exec call needed some time
        sleep( 1 );

    }
    catch( ssh::SshException e )
    {
        std::cout << "Error during connection : ";
        std::cout << e.getError() << std::endl;
    }

    return 0;
}