Re: ssh_pki_export_privkey_file for SSH_KEYTYPE_RSA key returns SSH_ERROR

[Jakub Jelen <jjelen@xxxxxxxxxx>]

On Mon, 2019-12-16 at 23:39 +0100, Torsten Kuehnel wrote:
> I'm new to programming using libssh. 
> 
> When i take the keygen.c example file in the examples directory, it
> fails during execution when i change the keytype.
> 
> [tdkuehnel@ multiboot examples]$ ./keygen 
> Failed to write private key file[tdkuehnel@ multiboot examples]$ 
> 
> /*    rv = ssh_pki_generate(SSH_KEYTYPE_ED25519, 0, &key);*/
>     rv = ssh_pki_generate(SSH_KEYTYPE_RSA, 1024, &key);
> 
> Do i miss additional steps in preparing the rsa key to be exported ?
> 
> Complete code:
> 
> #include <libssh/libssh.h>
> #include <stdio.h>
> 
> int main(void)
> {
>     ssh_key key = NULL;
>     int rv;
> 
>     /* Generate a new ED25519 private key file */
> /*    rv = ssh_pki_generate(SSH_KEYTYPE_ED25519, 0, &key);*/
>     rv = ssh_pki_generate(SSH_KEYTYPE_RSA, 1024, &key);
>     if (rv != SSH_OK) {
>         fprintf(stderr, "Failed to generate private key");
> 	return -1;
>     }
> 
>     /* Write it to a file testkey in the current dirrectory */
>     rv = ssh_pki_export_privkey_file(key, NULL, NULL, NULL,
> "testkey");
>     if (rv != SSH_OK) {
>         fprintf(stderr, "Failed to write private key file");
> 	return -1;
>     }
> 
>     return 0;
> }

This exact code works for me just fine and generates the testkey file
without any problem (with libssh-0.9.2-1.fc31.x86_64). Are you getting
the error from the key generation or export function?

$ gcc -lssh keygen.c -o keygen
$ ./keygen 
$ echo $?
0
$ cat testkey 
-----BEGIN PRIVATE KEY-----
[...]


Regards,
-- 
Jakub Jelen
Senior Software Engineer
Security Technologies
Red Hat, Inc.