ipv6: sr: add core files for SR HMAC support
This patch adds the necessary functions to compute and check the HMAC signature
of an SR-enabled packet. Two HMAC algorithms are supported: hmac(sha1) and
hmac(sha256).
In order to avoid dynamic memory allocation for each HMAC computation,
a per-cpu ring buffer is allocated for this purpose.
A new per-interface sysctl called seg6_require_hmac is added, allowing a
user-defined policy for processing HMAC-signed SR-enabled packets.
A value of -1 means that the HMAC field will always be ignored.
A value of 0 means that if an HMAC field is present, its validity will
be enforced (the packet is dropped is the signature is incorrect).
Finally, a value of 1 means that any SR-enabled packet that does not
contain an HMAC signature or whose signature is incorrect will be dropped.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/Kconfig b/net/ipv6/Kconfig
index 1123a00..0f00811 100644
--- a/net/ipv6/Kconfig
+++ b/net/ipv6/Kconfig
@@ -301,4 +301,16 @@
If unsure, say N.
+config IPV6_SEG6_HMAC
+ bool "IPv6: Segment Routing HMAC support"
+ depends on IPV6
+ select CRYPTO_HMAC
+ select CRYPTO_SHA1
+ select CRYPTO_SHA256
+ ---help---
+ Support for HMAC signature generation and verification
+ of SR-enabled packets.
+
+ If unsure, say N.
+
endif # IPV6