hi
I want to use ECC(ellyptic curve cryptography) for SSL-connections but somehow dovecot doesn't like my ECC-certificates :(
I tried to test using following scenario:
machine: debian 6 (x64) dovecot 2.0.15-0~auto+21 ((f6a2c0e8bc03) from http://xi.rename-it.nl/debian openssl 1.0.0e-2 from testing (as the default 0.9.8o-4squeeze3 needs also the parameter -cipher ECCdraft for testing)
creating keys+cert for ecc (i.e. curves prime192v1, secp521r1) # openssl ecparam -name prime192v1 -genkey -out prime192v1.key # openssl req -new -key prime192v1.key -out prime192v1.csr # openssl req -x509 -in prime192v1.csr -key prime192v1.key -out prime192v1.crt
testing these in 2 windows # openssl s_server -cert prime192v1.crt -key prime192v1.key -www # openssl s_client note: when using the default openssl version 0.9.8o-4squeeze3 you need to append -cipher ECCdraft
output (cut) ... New, TLSv1/SSLv3, Cipher is ECDHE-ECDSA-AES256-SHA Server public key is 192 bit Secure Renegotiation IS supported Compression: zlib compression Expansion: zlib compression SSL-Session: Protocol : SSLv3 Cipher : ECDHE-ECDSA-AES256-SHA Session-ID: xxxxx Session-ID-ctx: Master-Key: xxxxx Key-Arg : None PSK identity: None PSK identity hint: None Compression: 1 (zlib compression) Start Time: xxxxx Timeout : 7200 (sec) Verify return code: 18 (self signed certificate)
looks promising - also for the secp521r1 curve
but when changing dovecot.conf to use these keys and certificates it won't use them and return errors
# openssl s_client -port 993 CONNECTED(00000003) 140543456835240:error:14094410:SSL routines:SSL3_READ_BYTES:sslv3 alert handshake failure:s3_pkt.c:1195:SSL alert number 40 140543456835240:error:1409E0E5:SSL routines:SSL3_WRITE_BYTES:ssl handshake failure:s3_pkt.c:591:
no peer certificate available
No client certificate CA names sent
SSL handshake has read 7 bytes and written 0 bytes
New, (NONE), Cipher is (NONE) Secure Renegotiation IS NOT supported Compression: NONE Expansion: NONE SSL-Session: Protocol : SSLv3 Cipher : 0000 Session-ID: Session-ID-ctx: Master-Key: Key-Arg : None PSK identity: None PSK identity hint: None Start Time: xxxxx Timeout : 7200 (sec) Verify return code: 0 (ok)
and the log gives (using verbose_ssl = yes in dovecot.conf)
==> /var/log/mail.log <== dovecot: imap-login: Warning: SSL: where=0x10, ret=1: before/accept initialization [127.0.0.1]
==> /var/log/mail.info <== dovecot: imap-login: Warning: SSL: where=0x10, ret=1: before/accept initialization [127.0.0.1]
==> /var/log/mail.warn <== dovecot: imap-login: Warning: SSL: where=0x10, ret=1: before/accept initialization [127.0.0.1]
==> /var/log/mail.log <== dovecot: imap-login: Warning: SSL: where=0x2001, ret=1: before/accept initialization [127.0.0.1]
==> /var/log/mail.info <== dovecot: imap-login: Warning: SSL: where=0x2001, ret=1: before/accept initialization [127.0.0.1]
==> /var/log/mail.warn <== dovecot: imap-login: Warning: SSL: where=0x2001, ret=1: before/accept initialization [127.0.0.1]
==> /var/log/mail.log <== dovecot: imap-login: Warning: SSL alert: where=0x4008, ret=552: fatal handshake failure [127.0.0.1]
==> /var/log/mail.info <== dovecot: imap-login: Warning: SSL alert: where=0x4008, ret=552: fatal handshake failure [127.0.0.1]
==> /var/log/mail.warn <== dovecot: imap-login: Warning: SSL alert: where=0x4008, ret=552: fatal handshake failure [127.0.0.1]
==> /var/log/mail.log <== dovecot: imap-login: Warning: SSL: where=0x2002, ret=-1: SSLv3 read client hello C [127.0.0.1]
==> /var/log/mail.info <== dovecot: imap-login: Warning: SSL: where=0x2002, ret=-1: SSLv3 read client hello C [127.0.0.1]
==> /var/log/mail.warn <== dovecot: imap-login: Warning: SSL: where=0x2002, ret=-1: SSLv3 read client hello C [127.0.0.1]
==> /var/log/mail.log <== dovecot: imap-login: Warning: SSL: where=0x2002, ret=-1: SSLv3 read client hello C [127.0.0.1] dovecot: imap-login: Disconnected (no auth attempts): rip=127.0.0.1, lip=127.0.0.1, TLS handshaking: SSL_accept() failed: error:1408A0C1:SSL routines:SSL3_GET_CLIENT_HELLO:no shared cipher
==> /var/log/mail.info <== dovecot: imap-login: Warning: SSL: where=0x2002, ret=-1: SSLv3 read client hello C [127.0.0.1] dovecot: imap-login: Disconnected (no auth attempts): rip=127.0.0.1, lip=127.0.0.1, TLS handshaking: SSL_accept() failed: error:1408A0C1:SSL routines:SSL3_GET_CLIENT_HELLO:no shared cipher
==> /var/log/mail.warn <== dovecot: imap-login: Warning: SSL: where=0x2002, ret=-1: SSLv3 read client hello C [127.0.0.1]
from doveconf -a: ssl = required ssl_ca = ssl_cert =
Has anybody already tested this and made it working? Or do i have just to recompile everything to make it work?
Greetings
Mike