help! matching ciphers, but SSL3_GET_CLIENT_HELLO:no shared cipher shown in log

aoshea

Hi Guru's,

think I'm now out my depth, this was working, but changed UDP port as was getting hacked (shown 1194 in files, but this has been changed), additionally I've masked my ip with W.X.Y.Z

summary; openvpn connections from iPhone fail to OpenVPN, which is installed on a QNAP TS-269 Pro, log below:

[~] # telnet localhost 7505
>INFO:OpenVPN Management Interface Version 1 -- type 'help' for more info
?
ERROR: unknown command, enter 'help' for more options
help
Management Interface for OpenVPN 2.3.6 i686-pc-linux-gnu [SSL (OpenSSL)] [LZO] [EPOLL] [MH] [IPv6] built on Mar 11 2016
Commands:
auth-retry t : Auth failure retry mode (none,interact,nointeract).
bytecount n : Show bytes in/out, update every n secs (0=off).
echo [on|off] [N|all] : Like log, but only show messages in echo buffer.
exit|quit : Close management session.
forget-passwords : Forget passwords entered so far.
help : Print this message.
hold [on|off|release] : Set/show hold flag to on/off state, or
release current hold and start tunnel.
kill cn : Kill the client instance(s) having common name cn.
kill IP:port : Kill the client instance connecting from IP:port.
load-stats : Show global server load stats.
log [on|off] [N|all] : Turn on/off realtime log display
+ show last N lines or 'all' for entire history.
mute [n] : Set log mute level to n, or show level if n is absent.
needok type action : Enter confirmation for NEED-OK request of 'type',
where action = 'ok' or 'cancel'.
needstr type action : Enter confirmation for NEED-STR request of 'type',
where action is reply string.
net : (Windows only) Show network info and routing table.
password type p : Enter password p for a queried OpenVPN password.
remote type [host port] : Override remote directive, type=ACCEPT|MOD|SKIP.
proxy type [host port flags] : Enter dynamic proxy server info.
pid : Show process ID of the current OpenVPN process.
client-auth CID KID : Authenticate client-id/key-id CID/KID (MULTILINE)
client-auth-nt CID KID : Authenticate client-id/key-id CID/KID
client-deny CID KID R [CR] : Deny auth client-id/key-id CID/KID with log reason
text R and optional client reason text CR
client-kill CID [M] : Kill client instance CID with message M (def=RESTART)
env-filter [level] : Set env-var filter level
client-pf CID : Define packet filter for client CID (MULTILINE)
rsa-sig : Enter an RSA signature in response to >RSA_SIGN challenge
Enter signature base64 on subsequent lines followed by END
signal s : Send signal s to daemon,
s = SIGHUP|SIGTERM|SIGUSR1|SIGUSR2.
state [on|off] [N|all] : Like log, but show state history.
status [n] : Show current daemon status info using format #n.
test n : Produce n lines of output for testing/debugging.
username type u : Enter username u for a queried OpenVPN username.
verb [n] : Set log verbosity level to n, or show if n is absent.
version : Show current version number.
END
log on
SUCCESS: real-time log notification set to ON
>LOG:1468335369,,W.X.Y.Z:53610 TLS: Initial packet from [AF_INET]W.X.Y.Z:53610, sid=d1711c78 963beadc
>LOG:1468335369,N,W.X.Y.Z:53610 TLS_ERROR: BIO read tls_read_plaintext error: error:1408A0C1:SSL routines:SSL3_GET_CLIENT_HELLO:no shared cipher
>LOG:1468335369,N,W.X.Y.Z:53610 TLS Error: TLS object -> incoming plaintext read error
>LOG:1468335369,N,W.X.Y.Z:53610 TLS Error: TLS handshake failed
>LOG:1468335369,,W.X.Y.Z:53610 SIGUSR1[soft,tls-error] received, client-instance restarting
>LOG:1468335371,,W.X.Y.Z:53610 TLS: Initial packet from [AF_INET]W.X.Y.Z:53610, sid=d1711c78 963beadc
>LOG:1468335371,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335373,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335375,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335377,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335379,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335381,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335383,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335385,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335387,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335389,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335391,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335393,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335395,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335397,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335399,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335401,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335403,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335405,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335407,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335409,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335411,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335413,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335415,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335417,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335419,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335421,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335423,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335425,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335427,N,W.X.Y.Z:53610 TLS Error: reading acknowledgement record from packet
>LOG:1468335431,N,W.X.Y.Z:53610 TLS Error: TLS key negotiation failed to occur within 60 seconds (check your network connectivity)
>LOG:1468335431,N,W.X.Y.Z:53610 TLS Error: TLS handshake failed
>LOG:1468335431,,W.X.Y.Z:53610 SIGUSR1[soft,tls-error] received, client-instance restarting

aoshea

Client config file:
client
dev tun
script-security 3
proto udp
remote W.X.Y.Z 1194
resolv-retry infinite
nobind
ca ca.crt
auth-user-pass
reneg-sec 0
cipher AES-128-CBC
tls-cipher TLS-SRP-SHA-RSA-WITH-3DES-EDE-CBC-SHA:TLS-DHE-RSA-WITH-AES-128-CBC-SHA:TLS-DHE-RSA-WITH-AES-256-CBC-SHA
comp-lzo

server config file:
[/mnt/ext/opt/vpnopenvpn/etc/openvpn] # more server.conf
port 1194
proto udp
dev tun
ca /etc/openvpn/keys/ca.crt
cert /etc/openvpn/keys/myserver.crt
key /etc/openvpn/keys/myserver.key
auth-user-pass-verify /usr/sbin/vpn_check_account via-env
client-cert-not-required
username-as-common-name
no-name-remapping
dh /etc/openvpn/keys/dh1024.pem
server 172.16.30.0 255.255.255.0
ifconfig-pool-persist /var/log/ipp.txt
push "redirect-gateway def1"
push "dhcp-option DNS 8.8.8.8"
client-to-client
duplicate-cn
keepalive 10 60
reneg-sec 0
cipher AES-128-CBC
tls-cipher TLS-SRP-SHA-RSA-WITH-3DES-EDE-CBC-SHA:TLS-DHE-RSA-WITH-AES-128-CBC-SHA:TLS-DHE-RSA-WITH-AES-256-CBC-SHA
comp-lzo
max-clients 5
client-connect /etc/openvpn/connect.sh
client-disconnect /etc/openvpn/disconnect.sh
management localhost 7505
persist-key
persist-tun
status /var/log/openvpn-status.log
#log /tmp/openvpn.log
verb 3
[/mnt/ext/opt/vpnopenvpn/etc/openvpn] #

[/mnt/ext/opt/vpnopenvpn/etc/openvpn] # openvpn --show-tls | grep TLS-SRP-SHA-RSA
TLS-SRP-SHA-RSA-WITH-AES-256-CBC-SHA
TLS-SRP-SHA-RSA-WITH-AES-128-CBC-SHA
TLS-SRP-SHA-RSA-WITH-3DES-EDE-CBC-SHA

aoshea

[/mnt/ext/opt/vpnopenvpn/etc/openvpn] # openvpn --version
OpenVPN 2.3.6 i686-pc-linux-gnu [SSL (OpenSSL)] [LZO] [EPOLL] [MH] [IPv6] built on Mar 11 2016
library versions: OpenSSL 1.0.1s 1 Mar 2016, LZO 2.05
Originally developed by James Yonan
Copyright (C) 2002-2010 OpenVPN Technologies, Inc. <sales@openvpn.net>
Compile time defines: enable_crypto=yes enable_crypto_ofb_cfb=yes enable_debug=yes enable_def_auth=yes enable_dlopen=unknown enable_dlopen_self=unknown enable_dlopen_self_static=unknown enable_fast_install=yes enable_fragment=yes enable_http_proxy=yes enable_iproute2=no enable_libtool_lock=yes enable_lzo=yes enable_lzo_stub=no enable_management=yes enable_multi=yes enable_multihome=yes enable_pam_dlopen=no enable_password_save=yes enable_pedantic=no enable_pf=yes enable_pkcs11=no enable_plugin_auth_pam=yes enable_plugin_down_root=yes enable_plugins=yes enable_port_share=yes enable_selinux=no enable_server=yes enable_shared=yes enable_shared_with_static_runtimes=no enable_small=no enable_socks=yes enable_ssl=yes enable_static=yes enable_strict=no enable_strict_options=no enable_systemd=no enable_win32_dll=yes enable_x509_alt_username=no with_crypto_library=openssl with_gnu_ld=yes with_mem_check=no with_plugindir='$(libdir)/openvpn/plugins' with_sysroot=no
[/mnt/ext/opt/vpnopenvpn/etc/openvpn] #

[/mnt/ext/opt/vpnopenvpn/etc/openvpn] # openssl
OpenSSL> version
OpenSSL 1.0.1s 1 Mar 2016
OpenSSL>

TinCanTech

openvpn wrote$ openvpn --show-tls
Available TLS Ciphers,
listed in order of preference:

< etc >

Be aware that that whether a cipher suite in this list can actually work
depends on the specific setup of both peers. See the man page entries of
--tls-cipher and --show-tls for more details.

If you do not specify a cipher openvpn will select the best matching ciphers of both peers ..

aoshea

many thanks for responding TinCanTech, but unfortunately I'm none the wiser, the client.conf (openvpn.ovpn) & server.conf match;
openvpn.ovpn
cipher AES-128-CBC
tls-cipher TLS-SRP-SHA-RSA-WITH-3DES-EDE-CBC-SHA:TLS-DHE-RSA-WITH-AES-128-CBC-SHA:TLS-DHE-RSA-WITH-AES-256-CBC-SHA
server.conf
cipher AES-128-CBC
tls-cipher TLS-SRP-SHA-RSA-WITH-3DES-EDE-CBC-SHA:TLS-DHE-RSA-WITH-AES-128-CBC-SHA:TLS-DHE-RSA-WITH-AES-256-CBC-SHA

so haven't got a clue why when the iphone initiates the connection, the server says it hasn't a matching cipher; "no shared cipher"

not sure what I'm doing wrong.

thanks, Adrian

TinCanTech

aoshea wrotethe client.conf (openvpn.ovpn) & server.conf match;
openvpn.ovpn
cipher AES-128-CBC
tls-cipher TLS-SRP-SHA-RSA-WITH-3DES-EDE-CBC-SHA:TLS-DHE-RSA-WITH-AES-128-CBC-SHA:TLS-DHE-RSA-WITH-AES-256-CBC-SHA
server.conf
cipher AES-128-CBC
tls-cipher TLS-SRP-SHA-RSA-WITH-3DES-EDE-CBC-SHA:TLS-DHE-RSA-WITH-AES-128-CBC-SHA:TLS-DHE-RSA-WITH-AES-256-CBC-SHA

Openvpn relies on Openssl for these ciphers and so it is the openssl version that you have a problem with.

Remove --tls-cipher from both your client and server configs and let openvpn select the best match for you.
This should also show up in your log files so you can decide what to do next.

aoshea

many thanks for responding TinCanTech, it seems we were both investigating same issue at same time ;-)

I disabled encryption on server side, and ran client up and it connects, as below;
>LOG:1468352858,,W.X.Y.Z:55725 TLS: Initial packet from [AF_INET]W.X.Y.Z:55725, sid=ea087224 037161b6
>LOG:1468352865,I,my-secret-account/W.X.Y.Z:56802 [my-secret-account] Inactivity timeout (--ping-restart), restarting
>LOG:1468352865,,my-secret-account/W.X.Y.Z:56802 SIGUSR1[soft,ping-restart] received, client-instance restarting
>LOG:1468352872,,W.X.Y.Z:55725 TLS: Username/Password authentication succeeded for username 'my-secret-account' [CN SET]
>LOG:1468352872,W,W.X.Y.Z:55725 WARNING: 'link-mtu' is used inconsistently, local='link-mtu 1526', remote='link-mtu 1558'
>LOG:1468352872,W,W.X.Y.Z:55725 WARNING: 'cipher' is used inconsistently, local='cipher [null-cipher]', remote='cipher AES-128-CBC'
>LOG:1468352872,W,W.X.Y.Z:55725 WARNING: 'keysize' is used inconsistently, local='keysize 0', remote='keysize 128'
>LOG:1468352872,,W.X.Y.Z:55725 Data Channel Encrypt: Using 160 bit message hash 'SHA1' for HMAC authentication
>LOG:1468352872,,W.X.Y.Z:55725 Data Channel Decrypt: Using 160 bit message hash 'SHA1' for HMAC authentication
>LOG:1468352872,,W.X.Y.Z:55725 Control Channel: TLSv1, cipher TLSv1/SSLv3 EDH-RSA-DES-CBC3-SHA
>LOG:1468352872,I,W.X.Y.Z:55725 [my-secret-account] Peer Connection Initiated with [AF_INET]W.X.Y.Z:55725
>LOG:1468352872,I,my-secret-account/W.X.Y.Z:55725 MULTI_sva: pool returned IPv4=172.16.30.6, IPv6=(Not enabled)
>LOG:1468352886,,my-secret-account/W.X.Y.Z:55725 OPTIONS IMPORT: reading client specific options from: /tmp/openvpn_cc_af0581baddcc45e8e3cc5cf750c2a7ec.tmp
>LOG:1468352886,,my-secret-account/W.X.Y.Z:55725 MULTI: Learn: 172.16.30.6 -> my-secret-account/W.X.Y.Z:55725
>LOG:1468352886,,my-secret-account/W.X.Y.Z:55725 MULTI: primary virtual IP for my-secret-account/W.X.Y.Z:55725: 172.16.30.6
>CLIENT:ESTABLISHED,2
>CLIENT:ENV,n_clients=2

it does moan later on though;
>LOG:1468352785,N,my-secret-account/W.X.Y.Z:62543 Authenticate/Decrypt packet error: bad packet ID (may be a replay): [ #133570842 ] -- see the man page entry for --no-replay and --replay-window for more info or silence this warning with --mute-replay-warnings

will have a thorough look tomorrow (laptop with iTunes on it is elsewhere at moment and need that to push new profile to phone).

thanks again.

cheers Adrian

TinCanTech

This looks to me like you are running two very different versions of openvpn ..

Please see the Forum rules (top of this page) which explains what we need to know.
See --log and --verb in The Manual v23x

aoshea

many thanks for your help TinCanTech, problem is now resolved, I did a test with a win8 tablet I had and that worked, so knew it was the iPhone, for some reason there is a settings option which needed changing;

https://docs.openvpn.net/docs/openvpn-connect/openvpn-connect-ios-faq.html
Q: I cannot connect to the server (client times out), and the server log file shows "TLS_ERROR: BIO read tls_read_plaintext error: error:1408A0C1:SSL routines:SSL3_GET_CLIENT_HELLO:no shared cipher".
This is usually remedied by going to the OpenVPN section of the iOS Settings app and selecting "Force AES-CBC ciphersuites".

couldn't find this article yesterday when I googled it, but all is good now.

suspect I now need to find out how to generate new DH/RSA keys, as did the cardinal sin and emailed myself the cert/profile.

thanks again, cheers Adrian