ckarich

on my gentoo box, the update to curl-7.35 did the trick like I said above. had to restart apache though before it took effect (the version overview/information page in backWpup-Settings helped me noticing that)

but like i said before – there is no need for those 3 lines in the code. enforcing SSLv3 does not make sense to me from a security point of view. you should be fine commenting out the 3 occurences of that CURLOPT_SSLVERSION (see above). the connection still gets secured – the handshake should be done via tls instead.

so .. curl 7.35.0 installed on my machine and like suspected – the error ‘(35) Unsupported SSL protocol version’ is gone

anyhow – why is the plugin trying to enforce SSLv3? TLSv1 should be favourable since its an upgrade of the older SSLv3.

you cant? thats odd .. because here i can replicate the error with 7.34.0:

ckarich@xt ~ $ curl -v -I -3 https://www.google.com/
* Hostname was NOT found in DNS cache
* Trying 173.194.112.209…
* Adding handle: conn: 0x6585b0
* Adding handle: send: 0
* Adding handle: recv: 0
* Curl_addHandleToPipeline: length: 1
* – Conn 0 (0x6585b0) send_pipe: 1, recv_pipe: 0
* Connected to https://www.google.com (173.194.112.209) port 443 (#0)
* Unsupported SSL protocol version
* Closing connection 0
curl: (35) Unsupported SSL protocol version

curl 7.35.0 has been released (https://curl.haxx.se/changes.html#7_35_0)

couldnt try it out yet, because it not yet in my distros package management system.

it should fix the error 35 problem without any workarounds (filters, plugins, commenting out sections) – atleast thats my understanding of the underlying curl-problem. maybe anyone could test it and report back.

i temporarily commented out all occurences of

curl_setopt( $ch, CURLOPT_SSLVERSION, 3 )

in inc/class-destination-dropbox.php

this made the errormsg with unsupported ssl version go away but brings me to a new error message after the dropbox login:

Dropbox API: (77) error setting certificate verify locations: CAfile: /var/www/localhost/htdocs/_wp/wp-content/plugins/backwpup-master/vendor/dropbox-trusted-cert.crt CApath: /var/www/localhost/htdocs/_wp/wp-content/plugins/backwpup-master/vendor/

Using:

• WordPress version 3.8.1
• BackWPup version 3.1.2-beta3
• PHP version 5.5.7-pl0-gentoo
• MySQL version 5.1.70
• cURL version 7.34.0
• cURL SSL version OpenSSL/1.0.1e

Edit:
After copying the dropbox-trusted-cert.crt to ./vendor it worked.
File seems to be missing in 3.1.2-beta3 but is included in 3.1.2-beta2.

seems to be a known bug in the latest curl update – see https://sourceforge.net/p/curl/bugs/1319/

maybe its gone with the next release

hi Daniel,
I tried 3.1.2-bet2.
still the same error ??

Dropbox API: (35) Unsupported SSL protocol version

isnt there a usefull way to debug the error?