xfrm: Define new XFRM netlink auth attribute with specified truncation bits

The new XFRMA_ALG_AUTH_TRUNC attribute taking a xfrm_algo_auth as
argument allows the installation of authentication algorithms with
a truncation length specified in userspace, i.e. SHA256 with 128 bit
instead of 96 bit truncation.

Signed-off-by: Martin Willi <martin@strongswan.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 8 insertions, 0 deletions

diff --git a/include/linux/xfrm.h b/include/linux/xfrm.h
index 3246f0e66bcc..29e04beb1fc9 100644
--- a/include/linux/xfrm.h
+++ b/include/linux/xfrm.h
@@ -90,6 +90,13 @@ struct xfrm_algo {
         char            alg_key[0];
 };
 
+struct xfrm_algo_auth {
+        char            alg_name[64];
+        unsigned int    alg_key_len;    /* in bits */
+        unsigned int    alg_trunc_len;  /* in bits */
+        char            alg_key[0];
+};
+
 struct xfrm_algo_aead {
         char            alg_name[64];
         unsigned int    alg_key_len;    /* in bits */
@@ -274,6 +281,7 @@ enum xfrm_attr_type_t {
         XFRMA_MIGRATE,
         XFRMA_ALG_AEAD,         /* struct xfrm_algo_aead */
         XFRMA_KMADDRESS,        /* struct xfrm_user_kmaddress */
+        XFRMA_ALG_AUTH_TRUNC,   /* struct xfrm_algo_auth */
         __XFRMA_MAX
 
 #define XFRMA_MAX (__XFRMA_MAX - 1)