I'm trying to enable TLS in my ProFTPD server.
I created self signed certificate for that and configured tls as below,
<IfModule mod_tls.c>
TLSEngine on
TLSLog /var/log/proftpd/tls.log
TLSProtocol SSLv23
TLSRSACertificateFile /etc/ssl/certs/proftpd.crt
TLSRSACertificateKeyFile /etc/ssl/private/proftpd.key
TLSOptions NoSessionReuseRequired
TLSRequired on
</IfModule>
Now I'm getting below error when trying to connect using TLS.
2022-08-03 17:45:05,073 mod_tls/2.7[26337]: TLS/TLS-C requested, starting TLS handshake
2022-08-03 17:45:05,243 mod_tls/2.7[26337]: unable to accept TLS connection: protocol error: (1) error:14201076:SSL routines:tls_choose_sigalg:no suitable signature algorithm
2022-08-03 17:45:05,244 mod_tls/2.7[26337]: TLS/TLS-C negotiation failed on control channel
I have installed openssl version 1.1.1 and openssl list -cipher-algorithms give below list,
AES-128-CBC
AES-128-CBC-HMAC-SHA1
AES-128-CBC-HMAC-SHA256
id-aes128-CCM
AES-128-CFB
AES-128-CFB1
AES-128-CFB8
AES-128-CTR
AES-128-ECB
id-aes128-GCM
AES-128-OCB
AES-128-OFB
AES-128-XTS
AES-192-CBC
id-aes192-CCM
AES-192-CFB
AES-192-CFB1
AES-192-CFB8
AES-192-CTR
AES-192-ECB
id-aes192-GCM
AES-192-OCB
AES-192-OFB
AES-256-CBC
AES-256-CBC-HMAC-SHA1
AES-256-CBC-HMAC-SHA256
id-aes256-CCM
AES-256-CFB
AES-256-CFB1
AES-256-CFB8
AES-256-CTR
AES-256-ECB
id-aes256-GCM
AES-256-OCB
AES-256-OFB
AES-256-XTS
aes128 => AES-128-CBC
aes128-wrap => id-aes128-wrap
aes192 => AES-192-CBC
aes192-wrap => id-aes192-wrap
aes256 => AES-256-CBC
aes256-wrap => id-aes256-wrap
ARIA-128-CBC
ARIA-128-CCM
ARIA-128-CFB
ARIA-128-CFB1
ARIA-128-CFB8
ARIA-128-CTR
ARIA-128-ECB
ARIA-128-GCM
ARIA-128-OFB
ARIA-192-CBC
ARIA-192-CCM
ARIA-192-CFB
ARIA-192-CFB1
ARIA-192-CFB8
ARIA-192-CTR
ARIA-192-ECB
ARIA-192-GCM
ARIA-192-OFB
ARIA-256-CBC
ARIA-256-CCM
ARIA-256-CFB
ARIA-256-CFB1
ARIA-256-CFB8
ARIA-256-CTR
ARIA-256-ECB
ARIA-256-GCM
ARIA-256-OFB
aria128 => ARIA-128-CBC
aria192 => ARIA-192-CBC
aria256 => ARIA-256-CBC
bf => BF-CBC
BF-CBC
BF-CFB
BF-ECB
BF-OFB
blowfish => BF-CBC
CAMELLIA-128-CBC
CAMELLIA-128-CFB
CAMELLIA-128-CFB1
CAMELLIA-128-CFB8
CAMELLIA-128-CTR
CAMELLIA-128-ECB
CAMELLIA-128-OFB
CAMELLIA-192-CBC
CAMELLIA-192-CFB
CAMELLIA-192-CFB1
CAMELLIA-192-CFB8
CAMELLIA-192-CTR
CAMELLIA-192-ECB
CAMELLIA-192-OFB
CAMELLIA-256-CBC
CAMELLIA-256-CFB
CAMELLIA-256-CFB1
CAMELLIA-256-CFB8
CAMELLIA-256-CTR
CAMELLIA-256-ECB
CAMELLIA-256-OFB
camellia128 => CAMELLIA-128-CBC
camellia192 => CAMELLIA-192-CBC
camellia256 => CAMELLIA-256-CBC
cast => CAST5-CBC
cast-cbc => CAST5-CBC
CAST5-CBC
CAST5-CFB
CAST5-ECB
CAST5-OFB
ChaCha20
ChaCha20-Poly1305
des => DES-CBC
DES-CBC
DES-CFB
DES-CFB1
DES-CFB8
DES-ECB
DES-EDE
DES-EDE-CBC
DES-EDE-CFB
des-ede-ecb => DES-EDE
DES-EDE-OFB
DES-EDE3
DES-EDE3-CBC
DES-EDE3-CFB
DES-EDE3-CFB1
DES-EDE3-CFB8
des-ede3-ecb => DES-EDE3
DES-EDE3-OFB
DES-OFB
des3 => DES-EDE3-CBC
des3-wrap => id-smime-alg-CMS3DESwrap
desx => DESX-CBC
DESX-CBC
id-aes128-CCM
id-aes128-GCM
id-aes128-wrap
id-aes128-wrap-pad
id-aes192-CCM
id-aes192-GCM
id-aes192-wrap
id-aes192-wrap-pad
id-aes256-CCM
id-aes256-GCM
id-aes256-wrap
id-aes256-wrap-pad
id-smime-alg-CMS3DESwrap
rc2 => RC2-CBC
rc2-128 => RC2-CBC
rc2-40 => RC2-40-CBC
RC2-40-CBC
rc2-64 => RC2-64-CBC
RC2-64-CBC
RC2-CBC
RC2-CFB
RC2-ECB
RC2-OFB
RC4
RC4-40
RC4-HMAC-MD5
seed => SEED-CBC
SEED-CBC
SEED-CFB
SEED-ECB
SEED-OFB
sm4 => SM4-CBC
SM4-CBC
SM4-CFB
SM4-CTR
SM4-ECB
SM4-OFB
I cannot figure out what I'm missing here. Hope TLS experts can help me here.
Thank you!
CodePudding user response：
This kind of error happens if the signature on the certificate is using an old algorithm, like MD5 or SHA-1. Make sure to use SHA-2, i.e. SHA-256, SHA-284, .. instead.
Some tools still default to the default algorithm when creating certificates or some instructions found on the internet still show these algorithms. Modern TLS stacks instead enforce more secure defaults and then will complain that the signature algorithm on the certificate is too weak.