ipsec: add support of limited SA dump
The goal of this patch is to allow userland to dump only a part of SA by
specifying a filter during the dump.
The kernel is in charge to filter SA, this avoids to generate useless netlink
traffic (it save also some cpu cycles). This is particularly useful when there
is a big number of SA set on the system.
Note that I removed the union in struct xfrm_state_walk to fix a problem on arm.
struct netlink_callback->args is defined as a array of 6 long and the first long
is used in xfrm code to flag the cb as initialized. Hence, we must have:
sizeof(struct xfrm_state_walk) <= sizeof(long) * 5.
With the union, it was false on arm (sizeof(struct xfrm_state_walk) was
sizeof(long) * 7), due to the padding.
In fact, whatever the arch is, this union seems useless, there will be always
padding after it. Removing it will not increase the size of this struct (and
reduce it on arm).
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
diff --git a/include/uapi/linux/pfkeyv2.h b/include/uapi/linux/pfkeyv2.h
index 0b80c80..ada7f01 100644
--- a/include/uapi/linux/pfkeyv2.h
+++ b/include/uapi/linux/pfkeyv2.h
@@ -235,6 +235,18 @@
} __attribute__((packed));
/* sizeof(struct sadb_x_kmaddress) == 8 */
+/* To specify the SA dump filter */
+struct sadb_x_filter {
+ __u16 sadb_x_filter_len;
+ __u16 sadb_x_filter_exttype;
+ __u32 sadb_x_filter_saddr[4];
+ __u32 sadb_x_filter_daddr[4];
+ __u16 sadb_x_filter_family;
+ __u8 sadb_x_filter_splen;
+ __u8 sadb_x_filter_dplen;
+} __attribute__((packed));
+/* sizeof(struct sadb_x_filter) == 40 */
+
/* Message types */
#define SADB_RESERVED 0
#define SADB_GETSPI 1
@@ -358,7 +370,8 @@
#define SADB_X_EXT_SEC_CTX 24
/* Used with MIGRATE to pass @ to IKE for negotiation */
#define SADB_X_EXT_KMADDRESS 25
-#define SADB_EXT_MAX 25
+#define SADB_X_EXT_FILTER 26
+#define SADB_EXT_MAX 26
/* Identity Extension values */
#define SADB_IDENTTYPE_RESERVED 0