No safe ciphers supported

[RubenKelevra]

Actual behaviour

No connections possible with secure ciphers

Expected behaviour

Secure ciphers supported

Steps to reproduce

1. create a server with safe ciphers
2. start android app
3. try to connect

Environment data

Android version: latest stable

Device model: exchangeable

Stock or customized system: native android

Nextcloud app version: latest today

Nextcloud server version: 9.0.51

Nginx cipher config

ssl_ciphers ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-SHA384:ECDHE-RSA-AES128-SHA256:!MD5:!aNULL:!EDH:!RC4:!DSS;
ssl_prefer_server_ciphers on;

[AndyScherzinger]

cc @LukasReschke

Do we have any environments to test this scenario Lukas or could you @RubenKelevra provide us with a test account so we can debug this matter?
Another things is that I am not sure if this is a client matter since many people in the forums had client problems while using nginx since it seems the nginx configuration has to be rather specific.

[LukasReschke]

Please provide us with a link to your domain, @RubenKelevra.

[RubenKelevra]

@LukasReschke
https://cloud.itu2015.de

Just enter this as domain and the Android App says "SSL connection error" or similar.

This domain entered on chrome on the same device works. After removing my explicit ssl-ciphers this works also in the app.

[LukasReschke]

What Android version are you using?

[AndyScherzinger]

@LukasReschke and @RubenKelevra here is the stack trace I get when trying the URL and to me this seems to be a configuration issue to some extend:

08-30 18:07:25.201 25775-25831/com.nextcloud.android.beta E/GetRemoteStatusOperation: Connection check at https://cloud.itu2015.de: SSL exception
  javax.net.ssl.SSLHandshakeException: Handshake failed
      at com.android.org.conscrypt.OpenSSLSocketImpl.startHandshake(OpenSSLSocketImpl.java:429)
      at com.owncloud.android.lib.common.network.AdvancedSslSocketFactory.verifyPeerIdentity(AdvancedSslSocketFactory.java:248)
      at com.owncloud.android.lib.common.network.AdvancedSslSocketFactory.createSocket(AdvancedSslSocketFactory.java:185)
      at org.apache.commons.httpclient.HttpConnection.open(HttpConnection.java:707)
      at org.apache.commons.httpclient.MultiThreadedHttpConnectionManager$HttpConnectionAdapter.open(MultiThreadedHttpConnectionManager.java:1361)
      at org.apache.commons.httpclient.HttpMethodDirector.executeWithRetry(HttpMethodDirector.java:387)
      at org.apache.commons.httpclient.HttpMethodDirector.executeMethod(HttpMethodDirector.java:171)
      at org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:397)
      at org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:323)
      at com.owncloud.android.lib.common.OwnCloudClient.executeMethod(OwnCloudClient.java:222)
      at com.owncloud.android.lib.common.OwnCloudClient.executeMethod(OwnCloudClient.java:192)
      at com.owncloud.android.lib.resources.status.GetRemoteStatusOperation.tryConnection(GetRemoteStatusOperation.java:89)
      at com.owncloud.android.lib.resources.status.GetRemoteStatusOperation.run(GetRemoteStatusOperation.java:194)
      at com.owncloud.android.lib.common.operations.RemoteOperation.execute(RemoteOperation.java:136)
      at com.owncloud.android.operations.GetServerInfoOperation.run(GetServerInfoOperation.java:81)
      at com.owncloud.android.lib.common.operations.RemoteOperation.execute(RemoteOperation.java:136)
      at com.owncloud.android.services.OperationsService$ServiceHandler.nextOperation(OperationsService.java:489)
      at com.owncloud.android.services.OperationsService$ServiceHandler.handleMessage(OperationsService.java:425)
      at android.os.Handler.dispatchMessage(Handler.java:102)
      at android.os.Looper.loop(Looper.java:154)
      at android.os.HandlerThread.run(HandlerThread.java:61)
   Caused by: javax.net.ssl.SSLProtocolException: SSL handshake terminated: ssl=0x75c5e0c1c0: Failure in SSL library, usually a protocol error
  error:10000410:SSL routines:OPENSSL_internal:SSLV3_ALERT_HANDSHAKE_FAILURE (external/boringssl/src/ssl/s3_pkt.c:610 0x75d494eca0:0x00000001)
  error:1000009a:SSL routines:OPENSSL_internal:HANDSHAKE_FAILURE_ON_CLIENT_HELLO (external/boringssl/src/ssl/s3_clnt.c:764 0x75d720ef76:0x00000000)
      at com.android.org.conscrypt.NativeCrypto.SSL_do_handshake(Native Method)
      at com.android.org.conscrypt.OpenSSLSocketImpl.startHandshake(OpenSSLSocketImpl.java:357)
        ... 20 more

Or the SSL library can't handle this, don't know since I am not an SSL expert. My test is latest beta run on an Nexus5X with Android 7.0

[RubenKelevra]

@LukasReschke none, this was done on a phone of a friend which runs on android 7

[RubenKelevra]

@AndyScherzinger which infos do you need additional? :)

[AndyScherzinger]

@RubenKelevra I don't need any, the URL is fine for me looking at it from a client perspective, to try to further debug this matter. Not sure if anyone from the server/core team can support this matter, so cc @MorrisJobke @rullzer @nickvergessen

[rullzer]

I can't reproduce this on my android (with the same cipher list for nginx) it is running android 6.

This seems to be something not related to the server part but to the webserver config.

[RubenKelevra]

@rullzer I quoted the full full ssl-config of this server. I think it's might be related to "ssl_ecdh_curve secp384r1;" or a 4096 bit dhkey might be to large ... Actually Android since 4.x should support this options. :)

ssl_protocols TLSv1.2;
ssl_ecdh_curve secp384r1;
resolver 8.8.8.8;
ssl_stapling on;
ssl_stapling_verify on;

ssl_session_cache shared:SSL:10m;
ssl_session_timeout 10m;

ssl_certificate /etc/nginx/certs/cloud.itu2015.de.crt;
ssl_certificate_key /etc/nginx/certs/cloud.itu2015.de.key;

ssl_dhparam /etc/nginx/certs/cloud.itu2015.de.dh4096.pem;
ssl_trusted_certificate /etc/nginx/certs/startssl-ca-certs.pem;

ssl_ciphers ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-SHA384:ECDHE-RSA-AES128-SHA256:EECDH+AESGCM:EDH+AESGCM:AES256+EECDH:AES256+EDH:!MD5:!aNULL:!EDH:!RC4:!DSS;
ssl_prefer_server_ciphers on;

add_header Strict-Transport-Security "max-age=15768000; includeSubDomains; preload";
add_header X-Content-Type-Options nosniff;
add_header X-Frame-Options "SAMEORIGIN";
add_header X-XSS-Protection "1; mode=block";
add_header X-Robots-Tag none;
add_header X-Download-Options noopen;
add_header X-Permitted-Cross-Domain-Policies none;
add_header Public-Key-Pins 'max-age=5184000; pin-sha256="5C8kvU039KouVrl52D0eZSGf4Onjo4Khs8tmyTlV3nU="; pin-sha256="YLh1dUR9y6Kja30RrAn7JKnbQG/uEtLMkBgFF2Fuihg="';

[RubenKelevra]

@rullzer if you run your nginx with openssl please confirm the very latest version is installed, I use LibreSSL on all Servers because OpenSSL had no support for ChaCha20 until the very last version.

[rullzer]

I'm runnig dev-libs/openssl-1.0.2h-r2 (gentoo).
I could debug more but then I'll need to setup stuff in a docker/VM since I don't want to mess with my life instance ;)

[RubenKelevra]

@rullzer allright, feel free if to ask if you need some further infos :)

[hucste]

Hi...
I confirm this bad bogue. :(
Please, see all this nextcloud thread where i wroted informations.

It appear app android need SSLv3 connections and SHA1 cipher to connect at server NC.
If the server NC is correctly setted with ultra secured ciphers as 'EECDH+AES:+AES128:+AES256', those app Android can not connect. It's necessary to downgrade security SSL by adding ':SHA' as 'EECDH+AES:+AES128:+AES256:+SHA' to obtain connections!
But...

# openssl ciphers -v 'EECDH+AES:+AES128:+AES256:+SHA'
ECDHE-RSA-AES128-GCM-SHA256 TLSv1.2 Kx=ECDH     Au=RSA  Enc=AESGCM(128) Mac=AEAD
ECDHE-ECDSA-AES128-GCM-SHA256 TLSv1.2 Kx=ECDH     Au=ECDSA Enc=AESGCM(128) Mac=AEAD
ECDHE-RSA-AES128-SHA256 TLSv1.2 Kx=ECDH     Au=RSA  Enc=AES(128)  Mac=SHA256
ECDHE-ECDSA-AES128-SHA256 TLSv1.2 Kx=ECDH     Au=ECDSA Enc=AES(128)  Mac=SHA256
ECDHE-RSA-AES256-GCM-SHA384 TLSv1.2 Kx=ECDH     Au=RSA  Enc=AESGCM(256) Mac=AEAD
ECDHE-ECDSA-AES256-GCM-SHA384 TLSv1.2 Kx=ECDH     Au=ECDSA Enc=AESGCM(256) Mac=AEAD
ECDHE-RSA-AES256-SHA384 TLSv1.2 Kx=ECDH     Au=RSA  Enc=AES(256)  Mac=SHA384
ECDHE-ECDSA-AES256-SHA384 TLSv1.2 Kx=ECDH     Au=ECDSA Enc=AES(256)  Mac=SHA384
ECDHE-RSA-AES128-SHA    SSLv3 Kx=ECDH     Au=RSA  Enc=AES(128)  Mac=SHA1
ECDHE-ECDSA-AES128-SHA  SSLv3 Kx=ECDH     Au=ECDSA Enc=AES(128)  Mac=SHA1
ECDHE-RSA-AES256-SHA    SSLv3 Kx=ECDH     Au=RSA  Enc=AES(256)  Mac=SHA1
ECDHE-ECDSA-AES256-SHA  SSLv3 Kx=ECDH     Au=ECDSA Enc=AES(256)  Mac=SHA1

App Android can communicate only with 'ECDHE-RSA-AES128-SHA'.

I explain in other NC post why it's very bad.