libssh crypt_set_algorithms2 error

Question

Hi everyone I am trying to establish a simple ssh connection between a windows app (a program I wrote) and a ssh server. In my code I use libssh and I have an error like that: crypt_set_algorithms2: no crypto algorithm function found for 3des-cbc

The code I am using is:

#include <libssh/libssh.h>
#include <stdlib.h>
#include <stdio.h> 
int main()
{
    ssh_session my_ssh_session;
    int rc;
    int port = 22;
    int verbosity = SSH_LOG_PROTOCOL;
    char *password;
    // Open session and set options
    my_ssh_session = ssh_new();
    if (my_ssh_session == NULL)
        exit(-1);
    ssh_options_set(my_ssh_session, SSH_OPTIONS_HOST, "192.168.1.6");
    ssh_options_set(my_ssh_session, SSH_OPTIONS_USER, "john");
    ssh_options_set(my_ssh_session, SSH_OPTIONS_LOG_VERBOSITY, &verbosity);
    ssh_options_set(my_ssh_session, SSH_OPTIONS_CIPHERS_C_S,"aes128-ctr");

    //ssh_options_set(my_ssh_session, SSH_OPTIONS_PORT, &port);
    // Connect to server
    rc = ssh_connect(my_ssh_session);
    if (rc != SSH_OK)  
    {
        fprintf(stderr, "Error: %s\n", ssh_get_error(my_ssh_session)); //HERE IS WHERE I GET THE ERROR 
        ssh_free(my_ssh_session);
        exit(-1);
    }
    // Verify the server's identity
    // For the source code of verify_knowhost(), check previous example
/*  if (verify_knownhost(my_ssh_session) < 0)
    {
        ssh_disconnect(my_ssh_session);
        ssh_free(my_ssh_session);
        exit(-1);
    }
*/  
    // Authenticate ourselves
    password = "pass";
    rc = ssh_userauth_password(my_ssh_session, NULL, password);
    if (rc != SSH_AUTH_SUCCESS)
    {
        fprintf(stderr, "Error authenticating with password: %s\n",
            ssh_get_error(my_ssh_session));
        ssh_disconnect(my_ssh_session);
        ssh_free(my_ssh_session);
        exit(-1);
    }


        ssh_disconnect(my_ssh_session);
    ssh_free(my_ssh_session);
}

score 1 · Answer 1 · answered Nov 22 '15 at 14:41

Your programm specifies that the connection must use the aes128-ctr cipher, and does not list any alternatives. The error message you are getting suggest that the server does not support this cipher. Trying commenting out the SSH_OPTIONS_CIPHERS_C_S line, or change the argument to a list which includes a cipher supported by the server (based on what you say, 3des-cbc might work). To specify a list of ciphers, use a strings with comma seperated cipher names, e.g. "aes128-ctr,aes256-ctr,3des-cbc"

But unless you know what you are doing, just stick to the defaults, and do not specify any explicit ciphers.

libssh crypt_set_algorithms2 error

1 Answers1