Add a quick (?) note for users who may be having sendmail interoperability issues

due to the recent (FreeBSD-SA-15:10.openssl) OpenSSL change to reject 512 bit
DH parameters.  Affects 11-CURRENT and 10-STABLE.
This commit is contained in:
Gregory Neil Shapiro 2015-06-15 04:18:29 +00:00
parent 3e58ee7cf3
commit 2259642454

View File

@ -31,6 +31,30 @@ NOTE TO PEOPLE WHO THINK THAT FreeBSD 11.x IS SLOW:
disable the most expensive debugging functionality run
"ln -s 'abort:false,junk:false' /etc/malloc.conf".)
20150614:
The import of openssl to address the FreeBSD-SA-15:10.openssl
security advisory includes a change which rejects handshakes
with DH parameters below 768 bits. sendmail releases prior
to 8.15.2 (not yet released), defaulted to a 512 bit
DH parameter setting for client connections. To work around
this interoperability, sendmail can be configured to use a
2048 bit DH parameter by:
1. Edit /etc/mail/`hostname`.mc
2. If a setting for confDH_PARAMETERS does not exist or
exists and is set to a string beginning with '5',
replace it with '2'.
3. If a setting for confDH_PARAMETERS exists and is set to
a file path, create a new file with:
openssl dhparam -out /path/to/file 2048
4. Rebuild the .cf file:
cd /etc/mail/; make; make install
5. Restart sendmail:
cd /etc/mail/; make restart
A sendmail patch is coming, at which time this file will be
updated.
20150604:
Generation of legacy formatted entries have been disabled by default
in pwd_mkdb(8), as all base system consumers of the legacy formatted