sctp: Change defaults on cookie hmac selection

Recently I posted commit 3c68198e75 which made selection of the cookie hmac
algorithm selectable.  This is all well and good, but Linus noted that it
changes the default config:
http://marc.info/?l=linux-netdev&m=135536629004808&w=2

I've modified the sctp Kconfig file to reflect the recommended way of making
this choice, using the thermal driver example specified, and brought the
defaults back into line with the way they were prior to my origional patch

Also, on Linus' suggestion, re-adding ability to select default 'none' hmac
algorithm, so we don't needlessly bloat the kernel by forcing a non-none
default.  This also led me to note that we won't honor the default none
condition properly because of how sctp_net_init is encoded.  Fix that up as
well.

Tested by myself (allbeit fairly quickly).  All configuration combinations seems
to work soundly.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: David Miller <davem@davemloft.net>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: linux-sctp@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Neil Horman 2012-12-14 15:22:01 +00:00 committed by David S. Miller
parent 999a7c5776
commit 0d0863b020
2 changed files with 27 additions and 4 deletions

View File

@ -66,12 +66,36 @@ config SCTP_DBG_OBJCNT
'cat /proc/net/sctp/sctp_dbg_objcnt'
If unsure, say N
choice
prompt "Default SCTP cookie HMAC encoding"
default SCTP_COOKIE_HMAC_MD5
help
This option sets the default sctp cookie hmac algorithm
when in doubt select 'md5'
config SCTP_DEFAULT_COOKIE_HMAC_MD5
bool "Enable optional MD5 hmac cookie generation"
help
Enable optional MD5 hmac based SCTP cookie generation
select SCTP_COOKIE_HMAC_MD5
config SCTP_DEFAULT_COOKIE_HMAC_SHA1
bool "Enable optional SHA1 hmac cookie generation"
help
Enable optional SHA1 hmac based SCTP cookie generation
select SCTP_COOKIE_HMAC_SHA1
config SCTP_DEFAULT_COOKIE_HMAC_NONE
bool "Use no hmac alg in SCTP cookie generation"
help
Use no hmac algorithm in SCTP cookie generation
endchoice
config SCTP_COOKIE_HMAC_MD5
bool "Enable optional MD5 hmac cookie generation"
help
Enable optional MD5 hmac based SCTP cookie generation
default y
select CRYPTO_HMAC if SCTP_COOKIE_HMAC_MD5
select CRYPTO_MD5 if SCTP_COOKIE_HMAC_MD5
@ -79,7 +103,6 @@ config SCTP_COOKIE_HMAC_SHA1
bool "Enable optional SHA1 hmac cookie generation"
help
Enable optional SHA1 hmac based SCTP cookie generation
default y
select CRYPTO_HMAC if SCTP_COOKIE_HMAC_SHA1
select CRYPTO_SHA1 if SCTP_COOKIE_HMAC_SHA1

View File

@ -1191,9 +1191,9 @@ static int __net_init sctp_net_init(struct net *net)
net->sctp.cookie_preserve_enable = 1;
/* Default sctp sockets to use md5 as their hmac alg */
#if defined (CONFIG_CRYPTO_MD5)
#if defined (CONFIG_SCTP_DEFAULT_COOKIE_HMAC_MD5)
net->sctp.sctp_hmac_alg = "md5";
#elif defined (CONFIG_CRYPTO_SHA1)
#elif defined (CONFIG_SCTP_DEFAULT_COOKIE_HMAC_SHA1)
net->sctp.sctp_hmac_alg = "sha1";
#else
net->sctp.sctp_hmac_alg = NULL;