I have a question about uploading a file (text.txt) securely in PHP
using the SFTP protocol and a public/private key pair.
I have posted this question is several fora, but no one seems to know
for sure how to do it. Although I've received much advice, none of the
actual published examples (including those in the PHP Manual) are known
to work, and do not work for me. I know my parameters are okay, since
they work in CoreFTP and PuTTY, two manual applications that implement
SFTP with private keys. Also, the short FTP insecure example in the PHP
Manual works perfectly for me. There seem to be many subtle undocumented
issues with getting any of the published example code using private keys
to work. I'm inexperienced with SFTP and other advanced features of PHP
and am hoping to find a working example.
So far I have tried a number of examples using the ssh2 PHP extension
and the cURL PHP extension. They fail, and the error messages, if any,
are uninformative.
A little background:
I do website development work for two small companies on a Windows
computer (Apache/PHP 7), uploading to a remote production server
(VPS/cPanel/Centos). My local software versions are: Windows 10
Hone/2004, Bitnami WAMP/7.4.13-0, Apache/2.4.46 (Win64), OpenSSL/1.1.1h,
PHP/7.4.13, libssh2/1.9.0.
Where I am now is that I used cPanel on the remote server to install an
SSH/SFTP public key for a particular account. I then copied the
generated encrypted x.key and x.ppk private key files to my local
computer. Now I am ready to upload files securely, if only PHP made the
task easy. Unfortunately, it does not.
I know that phpseclib is available and is said to work well, but it is a
very large PHP source code library, so I'd rather use the php_ssh2.dll
or cURL PHP extension, or something similar.
In summary, I'm looking for someone who has successfully used SFTP file
upload with private key in PHP to share their code with me. I pledge to
test the code and post it further to help others with this difficult but
increasingly important and useful problem.
David Spector
Springtime Software
