if: Add ioctls to get RSS key and hash type/function.

It will be needed by hn(4) to configure its RSS key and hash
type/function in the transparent VF mode in order to match VF's
RSS settings. The description of the transparent VF mode and
the RSS hash value issue are here:
https://svnweb.freebsd.org/base?view=revision&revision=322299
https://svnweb.freebsd.org/base?view=revision&revision=322485

These are generic enough to promise two independent IOCs instead
of abusing SIOCGDRVSPEC.

Setting RSS key and hash type/function is a different story,
which probably requires more discussion.

Comment about UDP_{IPV4,IPV6,IPV6_EX} were only in the patch
in the review request; these hash types are standardized now.

Reviewed by:	gallatin
MFC after:	1 week
Sponsored by:	Microsoft
Differential Revision:	https://reviews.freebsd.org/D12174

2 files changed, 38 insertions, 0 deletions

diff --git a/sys/net/if.c b/sys/net/if.c
index 3e018a61f28d..bc6c5a2cfa80 100644
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -2661,6 +2661,8 @@ ifhwioctl(u_long cmd, struct ifnet *ifp, caddr_t data, struct thread *td)
 	case SIOCGIFMEDIA:
 	case SIOCGIFXMEDIA:
 	case SIOCGIFGENERIC:
+	case SIOCGIFRSSKEY:
+	case SIOCGIFRSSHASH:
 		if (ifp->if_ioctl == NULL)
 			return (EOPNOTSUPP);
 		error = (*ifp->if_ioctl)(ifp, cmd, data);
diff --git a/sys/net/if.h b/sys/net/if.h
index e3b801b8b9c5..91a6786d4fec 100644
--- a/sys/net/if.h
+++ b/sys/net/if.h
@@ -526,6 +526,42 @@ struct ifi2creq {
 	uint8_t data[8];	/* read buffer */
 }; 
 
+/*
+ * RSS hash.
+ */
+
+#define	RSS_FUNC_NONE		0		/* RSS disabled */
+#define	RSS_FUNC_PRIVATE	1		/* non-standard */
+#define	RSS_FUNC_TOEPLITZ	2
+
+#define	RSS_TYPE_IPV4		0x00000001
+#define	RSS_TYPE_TCP_IPV4	0x00000002
+#define	RSS_TYPE_IPV6		0x00000004
+#define	RSS_TYPE_IPV6_EX	0x00000008
+#define	RSS_TYPE_TCP_IPV6	0x00000010
+#define	RSS_TYPE_TCP_IPV6_EX	0x00000020
+#define	RSS_TYPE_UDP_IPV4	0x00000040
+#define	RSS_TYPE_UDP_IPV6	0x00000080
+#define	RSS_TYPE_UDP_IPV6_EX	0x00000100
+
+#define	RSS_KEYLEN		128
+
+struct ifrsskey {
+	char		ifrk_name[IFNAMSIZ];	/* if name, e.g. "en0" */
+	uint8_t		ifrk_func;		/* RSS_FUNC_ */
+	uint8_t		ifrk_spare0;
+	uint16_t	ifrk_keylen;
+	uint8_t		ifrk_key[RSS_KEYLEN];
+};
+
+struct ifrsshash {
+	char		ifrh_name[IFNAMSIZ];	/* if name, e.g. "en0" */
+	uint8_t		ifrh_func;		/* RSS_FUNC_ */
+	uint8_t		ifrh_spare0;
+	uint16_t	ifrh_spare1;
+	uint32_t	ifrh_types;		/* RSS_TYPE_ */
+};
+
 #endif /* __BSD_VISIBLE */
 
 #ifdef _KERNEL