This series consolidates and modernizes the lists of crypto algorithms
that are selected by the IPsec kconfig options, and adds CRYPTO_SEQIV
since it no longer gets selected automatically by other things.
See previous discussion at
https://lkml.kernel.org/netdev/[email protected]/T/#u
Changed v3 => v4:
- Don't say that AH is "NOT RECOMMENDED" by RFC 8221.
- Updated commit messages (added Acked-by tags, fixed a bad Fixes tag,
added some more explanation to patch 3).
Eric Biggers (3):
esp, ah: consolidate the crypto algorithm selections
esp: select CRYPTO_SEQIV
esp, ah: modernize the crypto algorithm selections
net/ipv4/Kconfig | 34 ++++++++++++++++++----------------
net/ipv6/Kconfig | 34 ++++++++++++++++++----------------
net/xfrm/Kconfig | 24 ++++++++++++++++++++++++
3 files changed, 60 insertions(+), 32 deletions(-)
base-commit: 89dc68533b190117e1a2fb4298d88b96b3580abf
--
2.26.2
From: Eric Biggers <[email protected]>
The crypto algorithms selected by the ESP and AH kconfig options are
out-of-date with the guidance of RFC 8221, which lists the legacy
algorithms MD5 and DES as "MUST NOT" be implemented, and some more
modern algorithms like AES-GCM and HMAC-SHA256 as "MUST" be implemented.
But the options select the legacy algorithms, not the modern ones.
Therefore, modify these options to select the MUST algorithms --
and *only* the MUST algorithms.
Also improve the help text.
Note that other algorithms may still be explicitly enabled in the
kconfig, and the choice of which to actually use is still controlled by
userspace. This change only modifies the list of algorithms for which
kernel support is guaranteed to be present.
Suggested-by: Herbert Xu <[email protected]>
Suggested-by: Steffen Klassert <[email protected]>
Acked-by: Herbert Xu <[email protected]>
Cc: Corentin Labbe <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Eric Biggers <[email protected]>
---
net/ipv4/Kconfig | 18 ++++++++++++++++--
net/ipv6/Kconfig | 18 ++++++++++++++++--
net/xfrm/Kconfig | 15 +++++++++------
3 files changed, 41 insertions(+), 10 deletions(-)
diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig
index 39a7a21744dc03..dc9dfaef77e5a4 100644
--- a/net/ipv4/Kconfig
+++ b/net/ipv4/Kconfig
@@ -342,7 +342,14 @@ config INET_AH
tristate "IP: AH transformation"
select XFRM_AH
---help---
- Support for IPsec AH.
+ Support for IPsec AH (Authentication Header).
+
+ AH can be used with various authentication algorithms. Besides
+ enabling AH support itself, this option enables the generic
+ implementations of the algorithms that RFC 8221 lists as MUST be
+ implemented. If you need any other algorithms, you'll need to enable
+ them in the crypto API. You should also enable accelerated
+ implementations of any needed algorithms when available.
If unsure, say Y.
@@ -350,7 +357,14 @@ config INET_ESP
tristate "IP: ESP transformation"
select XFRM_ESP
---help---
- Support for IPsec ESP.
+ Support for IPsec ESP (Encapsulating Security Payload).
+
+ ESP can be used with various encryption and authentication algorithms.
+ Besides enabling ESP support itself, this option enables the generic
+ implementations of the algorithms that RFC 8221 lists as MUST be
+ implemented. If you need any other algorithms, you'll need to enable
+ them in the crypto API. You should also enable accelerated
+ implementations of any needed algorithms when available.
If unsure, say Y.
diff --git a/net/ipv6/Kconfig b/net/ipv6/Kconfig
index 70313f16319dd2..414a68b16869ec 100644
--- a/net/ipv6/Kconfig
+++ b/net/ipv6/Kconfig
@@ -51,7 +51,14 @@ config INET6_AH
tristate "IPv6: AH transformation"
select XFRM_AH
---help---
- Support for IPsec AH.
+ Support for IPsec AH (Authentication Header).
+
+ AH can be used with various authentication algorithms. Besides
+ enabling AH support itself, this option enables the generic
+ implementations of the algorithms that RFC 8221 lists as MUST be
+ implemented. If you need any other algorithms, you'll need to enable
+ them in the crypto API. You should also enable accelerated
+ implementations of any needed algorithms when available.
If unsure, say Y.
@@ -59,7 +66,14 @@ config INET6_ESP
tristate "IPv6: ESP transformation"
select XFRM_ESP
---help---
- Support for IPsec ESP.
+ Support for IPsec ESP (Encapsulating Security Payload).
+
+ ESP can be used with various encryption and authentication algorithms.
+ Besides enabling ESP support itself, this option enables the generic
+ implementations of the algorithms that RFC 8221 lists as MUST be
+ implemented. If you need any other algorithms, you'll need to enable
+ them in the crypto API. You should also enable accelerated
+ implementations of any needed algorithms when available.
If unsure, say Y.
diff --git a/net/xfrm/Kconfig b/net/xfrm/Kconfig
index b2ff8df2c836ef..e77ba529229cf5 100644
--- a/net/xfrm/Kconfig
+++ b/net/xfrm/Kconfig
@@ -67,26 +67,29 @@ config XFRM_STATISTICS
If unsure, say N.
+# This option selects XFRM_ALGO along with the AH authentication algorithms that
+# RFC 8221 lists as MUST be implemented.
config XFRM_AH
tristate
select XFRM_ALGO
select CRYPTO
select CRYPTO_HMAC
- select CRYPTO_MD5
- select CRYPTO_SHA1
+ select CRYPTO_SHA256
+# This option selects XFRM_ALGO along with the ESP encryption and authentication
+# algorithms that RFC 8221 lists as MUST be implemented.
config XFRM_ESP
tristate
select XFRM_ALGO
select CRYPTO
+ select CRYPTO_AES
select CRYPTO_AUTHENC
- select CRYPTO_HMAC
- select CRYPTO_MD5
select CRYPTO_CBC
- select CRYPTO_SHA1
- select CRYPTO_DES
select CRYPTO_ECHAINIV
+ select CRYPTO_GCM
+ select CRYPTO_HMAC
select CRYPTO_SEQIV
+ select CRYPTO_SHA256
config XFRM_IPCOMP
tristate
--
2.26.2
On Wed, Jun 10, 2020 at 09:14:34AM -0700, Eric Biggers wrote:
> This series consolidates and modernizes the lists of crypto algorithms
> that are selected by the IPsec kconfig options, and adds CRYPTO_SEQIV
> since it no longer gets selected automatically by other things.
>
> See previous discussion at
> https://lkml.kernel.org/netdev/[email protected]/T/#u
>
> Changed v3 => v4:
> - Don't say that AH is "NOT RECOMMENDED" by RFC 8221.
> - Updated commit messages (added Acked-by tags, fixed a bad Fixes tag,
> added some more explanation to patch 3).
Series applied to the ipsec tree, thanks a lot Eric!