I have this problem with Exim. DKIM fails on signing outgoing mails.
This is the /var/log/exim4/mainlog output (Debian Squeeze):
2012-08-02 17:11:33 1Sx1k5-0004Tk-9D <= me@my_domain.com U=me P=local S=399
2012-08-02 17:11:33 1Sx1k5-0004Tk-9D DKIM: signing failed (RC -101)
2012-08-02 17:11:33 1Sx1k5-0004Tk-9D => [email protected] R=dnslookup T=remote_smtp H=gmail-smtp-in.l.google.com [173.194.77.27] X=TLS1.0:RSA_ARCFOUR_SHA1:16 DN="C=US,ST=California,L=Mountain View,O=Google Inc,CN=mx.google.com"
The version of Exim running is: Exim version 4.72 Berkeley DB: Berkeley DB 4.8.30: (April 9, 2010) Support for: crypteq iconv() IPv6 GnuTLS move_frozen_messages DKIM
As I've readed here:
Hey Jon, The error: “DKIM: signing failed (RC -101)” is the error code PDKIM_ERR_RSA_PRIVKEY (from src/pdkim/pdkim.h)
/* Function success / error codes */ #define PDKIM_OK 0 #define PDKIM_FAIL -1 #define PDKIM_ERR_OOM -100 #define PDKIM_ERR_RSA_PRIVKEY -101 #define PDKIM_ERR_RSA_SIGNING -102 #define PDKIM_ERR_LONG_LINE -103 #define PDKIM_ERR_BUFFER_TOO_SMALL -104
and is only returned in one place – in src/pdkim/pdkim.c
/* Perform private key operation */ if(rsa_parse_key(&rsa, (unsigned char *)sig->rsa_privkey, strlen(sig->rsa_privkey), NULL, 0) != 0) { return PDKIM_ERR_RSA_PRIVKEY; }
So it looks like there is a problem parsing the RSA key that you generated for Exim. This could be because the key generation failed, or because exim doesn’t have access to the file (file permissions). I would start by trying to re-generate your certificates.
So the problem is in the private key.
I've tried generating different keys but no matter what private key I use, Exim still logging: DKIM: signing failed (RC -101).
I've tried:
# openssl genrsa -out dkim.private.key 768
then
# openssl genrsa -out dkim.private.key 1024
then
# openssl genrsa -out private.key 768
or
# openssl genrsa -out private.key 1024
even I've tried this DKIM Key Generation Wizard but the error is still there.
This is the Exim config section for DKIM (from /etc/exim4/exim4.conf.template):
remote_smtp:
debug_print = "T: remote_smtp for $local_part@$domain"
driver = smtp
dkim_domain = my_domain.com
dkim_selector = dkim
dkim_private_key = private.key
dkim_canon = relaxed
the keys I'm using are in /etc/exim4 to avoid permissions issues
Has anyone any idea? How can I solve this and get my outgoing mails signed
sudo su -l -s /bin/bash -c 'cat /etc/exim4/private.key' exim
chmod 400
) and refuses to use it if it's world-readable. Try turning off group and world permissions for the key.