exec-on-board

Single-binary easy-to-use tool for downloading files via Telnet + TFTP written in pure C.

Usually, embedded devices have Telnet and TFTP servers installed for command line access and file downloading/uploading, respectively. You can use this tool to ease the manual task of downloading some files from your target device or executing arbitrary commands on the device.

Setup

Build with make and you're good to go.

Usage

• Replace .command with the command you want to execute on the remote Telnet server, then build with make.

static telnet_cmd_data tmp_get_backup_cmd = {
    .command            = "tftp -g -l sample_file 192.168.1.3 12345",
    .error_substr       = "tftp:",
};

I was using this tool for only one task (downloading sample_file from the router), but you can easily extend this program by reading the command from the file, for example.

• Run ./exec_on_board (probably on your device's LAN host)

-h, --help                                 Display this message.
-q, --quiet                                Produce no output.
-u, --username=<username>                  Specify username for telnet server. Default value is "admin".
-p, --password=<password>                  Specify password for telnet server. Default value is "admin".
-a, --addr=<[ipaddr][:port]>               Specify board address and telnet port. Default value is "192.168.1.1:23".
-t, --tftp-addr=<[ipaddr][:port]>          Specify address and port for tftp server. Default value is "192.168.1.3:12345".
    --tftp-dir=<dir>                       Specify directory for tftp server. Default value is ".".
    --cl-prompt=<str>                      Specify command line prompt. Default value is "root@rtr:~#".
    --login-prompt=<str>                   Specify login prompt. Default value is "login:".
    --pwd-prompt=<str>                     Specify password prompt. Default value is "Password:".