"No shared cipher" error but listed in preferred ciphers

[Nicolas Godbert]

Hello,

I try to recycle some old HPE switches as radius client using EAP-TLS 
based protocols for test only.
They are using old deprecated ciphers, so i rebuild openssl for legacy 
suites on a raspbian (I know, it's bad idea and not secure).

# openssl ciphers -v ALL | grep RC4
RC4-MD5                        SSLv3   Kx=RSA      Au=RSA  Enc=RC4(128)  
              Mac=MD5

So, when the server freeradius and the switch try to negociate, i can 
see in the logs that the cipher RC4-MD5 is now common for the two devices.

...
Thu Nov 20 15:11:44 2025 : Debug: (26) eap_ttls: Authenticate
Thu Nov 20 15:11:44 2025 : Debug: (26) eap_ttls: (TLS) EAP Continuing ...
Thu Nov 20 15:11:44 2025 : Debug: (26) eap_ttls: (TLS) EAP Peer sent 
flags ---
Thu Nov 20 15:11:44 2025 : Debug: (26) eap_ttls: (TLS) EAP Verification 
says ok
Thu Nov 20 15:11:44 2025 : Debug: (26) eap_ttls: (TLS) EAP Done initial 
handshake
Thu Nov 20 15:11:44 2025 : Debug: (26) eap_ttls: (TLS) TTLS - Handshake 
state [PINIT] - before SSL initialization (0)
Thu Nov 20 15:11:44 2025 : Debug: (26) eap_ttls: (TLS) TTLS - Handshake 
state [PINIT] - Server before SSL initialization (0)
Thu Nov 20 15:11:44 2025 : Debug: (TLS) Ignoring cbtls_msg call with 
pseudo content type 256, version 00000301
Thu Nov 20 15:11:44 2025 : Debug: (26) eap_ttls: (TLS) TTLS - Handshake 
state [PINIT] - Server before SSL initialization (0)
Thu Nov 20 15:11:44 2025 : Debug: (TLS) Received 58 bytes of TLS data
Thu Nov 20 15:11:44 2025 : Debug: (TLS)        01 00 00 36 03 01 cf 30 
f0 07 73 5d 30 36 71 27
Thu Nov 20 15:11:44 2025 : Debug: (TLS)        65 2c ce 16 e6 41 0c 35 
b4 d3 4c 9d 3a d2 8e 78
Thu Nov 20 15:11:44 2025 : Debug: (TLS)        a9 5b 3d ac a5 a9 00 00 
04 00 04 00 ff 01 00 00
Thu Nov 20 15:11:44 2025 : Debug: (TLS)        09 00 23 00 00 00 0f 00 
01 01
Thu Nov 20 15:11:44 2025 : Debug: (26) eap_ttls: (TLS) TTLS - recv TLS 
1.3 Handshake, ClientHello
Thu Nov 20 15:11:44 2025 : Debug: (TLS) Ignoring cbtls_msg call with 
pseudo content type 256, version 00000301
Thu Nov 20 15:11:44 2025 : Debug: (TLS) Received 2 bytes of TLS data
Thu Nov 20 15:11:44 2025 : Debug: (TLS)        02 28
Thu Nov 20 15:11:44 2025 : Debug: (26) eap_ttls: (TLS) TTLS - send TLS 
1.0 Alert, fatal handshake_failure
Thu Nov 20 15:11:44 2025 : ERROR: (26) eap_ttls: (TLS) TTLS - Alert 
write:fatal:handshake failure
Thu Nov 20 15:11:44 2025 : ERROR: (26) eap_ttls: (TLS) TTLS - Server : 
Error in error
Thu Nov 20 15:11:44 2025 : Debug: (26) eap_ttls: Server preferred 
ciphers (by priority)
Thu Nov 20 15:11:44 2025 : Debug: (26) eap_ttls: (TLS)    [0] 
TLS_AES_256_GCM_SHA384
Thu Nov 20 15:11:44 2025 : Debug: (26) eap_ttls: (TLS)    [1] 
TLS_CHACHA20_POLY1305_SHA256
...
Thu Nov 20 15:11:44 2025 : Debug: (26) eap_ttls: (TLS)    [166] RC4-MD5
Thu Nov 20 15:11:44 2025 : Debug: (26) eap_ttls: (TLS)    [167] PSK-RC4-SHA
Thu Nov 20 15:11:44 2025 : Debug: (26) eap_ttls: (TLS) TTLS - Client 
preferred ciphers (by priority)
Thu Nov 20 15:11:44 2025 : Debug: (26) eap_ttls: (TLS)    [0] RC4-MD5
...

But i still got an error "no shared cipher"

...
Thu Nov 20 15:11:44 2025 : ERROR: (26) eap_ttls: (TLS) Failed reading 
from OpenSSL: ../ssl/statem/statem_srvr.c[2333]:error:0A0000C1:SSL 
routines::no shared cipher
Thu Nov 20 15:11:44 2025 : ERROR: (26) eap_ttls: (TLS) System call (I/O) 
error (-1)
Thu Nov 20 15:11:44 2025 : ERROR: (26) eap_ttls: (TLS) EAP Receive 
handshake failed during operation
Thu Nov 20 15:11:44 2025 : ERROR: (26) eap_ttls: [eaptls process] = fail
Thu Nov 20 15:11:44 2025 : ERROR: (26) eap: Failed continuing EAP TTLS 
(21) session.  EAP sub-module failed
...

Below, some samples of my configuration:

## cat /etc/os-release
PRETTY_NAME="Raspbian GNU/Linux 13 (trixie)"

## dpkg -l | grep freeradius
ii  freeradius                           3.2.7+dfsg-1+deb13u1+rpt1

## mods-available/eap ##
eap {
     default_eap_type = tls
     ...
     tls-config tls-common {
         ...
         cipher_list = "ALL at SECLEVEL=0"
         cipher_server_preference = no
         tls_min_version = "1.0"
         tls_max_version = "1.3"
         ecdh_curve = ""
     ...
...

## /etc/ssl/openssl_legacy.cnf ##
[openssl_init]
providers = provider_sect

[provider_sect]
default = system_default_sect
legacy = legacy_sect

[legacy_sect]
activate = 1
MinProtocol = SSLv3
CipherString = ALL at SECLEVEL=0

[system_default_sect]
activate = 1
MinProtocol = SSLv3
CipherString = ALL at SECLEVEL=0

Is this mandatory to use tls_min_version/max options since the 
deprecated cipher i try to use belong to SSLv3 suite ?

Do you have some hints to help debug further please ?
Thank you in advance.

Best regards,

-- 
Nicolas Godbert