Summary: Is there a known problem with SSH and RSA keys with 4096 bits? Recently I noticed that using the SFTP plugin of my favorite editor jedit wasn't working anymore. To make a long story short: I've drilled down the problem to the library JSch (jsch-0.1.54.jar) and compiled one of your example:
I'm using UserAuthPubKey.java (http://www.jcraft.com/jsch/examples/UserAuthPubKey.java.html) example with a 2 different keys: % ssh-keygen -lf ~/.ssh/id_rsa-2048 2048 SHA256:e8G+h4MsuUMZYUbk2jhk18FGQ88JNB/Lpxzpw/kfAeY erik.was...@namm.de (RSA) % ssh-keygen -lf ~/.ssh/id_rsa-4096 4096 SHA256:3M4Mx6KUodWqWfdVWOr0cavdapf8y+zIH3bXcl7umbo erik.was...@namm.de (RSA) The first one is working fine, that last one returns the following message > com.jcraft.jsch.JSchException: invalid privatekey: [B@f5f2bb7 throwing from the code snippet > jsch.addIdentity(chooser.getSelectedFile().getAbsolutePath()); If've modified UserAuthPubKey.java a little bit to drill down the JSchException. Here's the relevant part: if(returnVal == JFileChooser.APPROVE_OPTION) { System.out.println("You chose "+ chooser.getSelectedFile().getAbsolutePath()+"."); System.out.println("before jsch.addIdentity()"); jsch.addIdentity(chooser.getSelectedFile().getAbsolutePath()); System.out.println("after jsch.addIdentity()"); } Compiling (using the oracle JDK 1.8.0_101): % javac -classpath jsch.jar UserAuthPubKey.java Starting and using the 2048 bit key: % java -classpath jsch.jar:. UserAuthPubKey You chose /home/brassel/.ssh/id_rsa-2048. before jsch.addIdentity() after jsch.addIdentity() ...Program goes on... Starting and using the 4096 bit key: % java -classpath jsch.jar:. UserAuthPubKey You chose /home/brassel/.ssh/id_rsa-4096. before jsch.addIdentity() com.jcraft.jsch.JSchException: invalid privatekey: [B@48140564 ...Program ends here... Why is that? Why are 4096 bits RSA keys invalid? How can I fix this issue? -- So long... Erik ------------------------------------------------------------------------------ Developer Access Program for Intel Xeon Phi Processors Access to Intel Xeon Phi processor-based developer platforms. With one year of Intel Parallel Studio XE. Training and support from Colfax. Order your platform today. http://sdm.link/xeonphi _______________________________________________ JSch-users mailing list JSch-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/jsch-users
