secp521r1 → javax.net.ssl.SSLHandshakeException: Handshake failed
GuilleW last edited by rfc2822
Hi. I’m using Nextcloud and DAVx⁵ to sync.
Since DAVx⁵ 2.5.x, it doesn’t work due to modern cyphers. So I try new updates and downgrade to 2.4.x each time if it doesn’t work.
But 2.4.x versions are not available anymore on F-droid, and now I can’t sync my cals anymore.
Here’s the log.
Please set your server to correct TLS ciphers (according to TLS specs), then it should work.
If you really need an old DAVx⁵ version (which should only be necessary for Android <4.4): https://www.davx5.com/faq/can-i-use-davdroid-with-an-old-android-version
Hi, and thank you for the fast reply.
I think I already do that, but in that case how to find cyphers missing in my conf ?
@GuilleW Hard to say… Conscrypt provides those protocols/ciphers: https://github.com/google/conscrypt/blob/master/CAPABILITIES.md
Which protocols/ciphers does your server allow/require?
Is your server publicly accessible?
devvv4ever last edited by
@GuilleW Also try to change the network method (WiFi / mobile) and try again. Maybe some firewall or so interrupts the connection.
@devvv4ever Already tested, Wifi at home and 4G at work, same issue.
I’m using Samsung Galaxy Note 3 (SM-N9005) on Android 5.0
Tested and working versions of DAVx⁵
I have just used your nginx config on our server for testing and it syncs without problems with DAVx⁵ 2.5.1 (Android 4.4 + 8)…
@rfc2822 It’s good to know that my server config is right.
But if the problem comes from my Samsung device…
The log file (davx5-info.txt) talk about a
I don’t understand why JAVA wants to use this protocol and not others available.
Unfortunately, I won’t be able to provide any additional info unless I can give a try on the server myself…
I updated my nextcloud instance to “Nextcloud 15.0.10” and try the last update “DAVx⁵ 2.5.2-ose”.
Still not work, so… back to “DAVx⁵ 184.108.40.206-ose”.
I prefer keep my server private, but can I send you a shared calendar on my Nextcloud in PM ?
@GuilleW Of course
Link sent in PM !
Thanks! Can you send your Web server configuration (SSL parameters), too? For some reason, the server denies new DAVx⁵ requests with “Handshake failure”, but there is no more information. I have checked ciphers etc. and they don’t seem to be the problem.
GuilleW last edited by GuilleW
My Nginx config is online on my Gitlab repo :
All about SSL is in /etc/nginx/conf.d/ssl.conf file
And Nextcloud domain config is here /etc/nginx/sites-available/nextcloud
Does it work when you use the secp384r1 curve (
Seems that Google doesn’t consider secp521r1 to be part of recommended curves (anymore), why it has been removed from Chrome and also from Conscrypt. Strange thing… but it should work with x25519, secp256r1 and secp384r1.
Thank you for advices.
I removed data of DAVx⁵ app, then uninstalled it.
I did a clean install of DAVx⁵ 2.5.2-ose.
Now, sync works perfectly ! (Yey!) but … now when I tap the + button on S planer (Samsung app for calendar) to add an event on Test calendar, it crash.
Back to “DAVx⁵ 220.127.116.11-ose”, S Planner still crash.
I’ll update nextcloud to Nextcloud 16.0.3.