summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
Diffstat
-rw-r--r--Documentation/netlink/specs/ethtool.yaml4
-rw-r--r--Documentation/networking/ethtool-netlink.rst6
-rw-r--r--Documentation/networking/scaling.rst15
-rw-r--r--include/linux/ethtool.h6
-rw-r--r--include/uapi/linux/ethtool.h13
-rw-r--r--include/uapi/linux/ethtool_netlink.h1
-rw-r--r--net/ethtool/ioctl.c30
-rw-r--r--net/ethtool/rss.c5
8 files changed, 74 insertions, 6 deletions
diff --git a/Documentation/netlink/specs/ethtool.yaml b/Documentation/netlink/specs/ethtool.yaml
index 5c7a65b009b4..197208f419dc 100644
--- a/Documentation/netlink/specs/ethtool.yaml
+++ b/Documentation/netlink/specs/ethtool.yaml
@@ -908,6 +908,9 @@ attribute-sets:
-
name: hkey
type: binary
+ -
+ name: input_xfrm
+ type: u32
-
name: plca
attributes:
@@ -1598,6 +1601,7 @@ operations:
- hfunc
- indir
- hkey
+ - input_xfrm
dump: *rss-get-op
-
name: plca-get-cfg
diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
index 6a49624a9cbf..d583d9abf2f8 100644
--- a/Documentation/networking/ethtool-netlink.rst
+++ b/Documentation/networking/ethtool-netlink.rst
@@ -1774,12 +1774,16 @@ Kernel response contents:
``ETHTOOL_A_RSS_HFUNC`` u32 RSS hash func
``ETHTOOL_A_RSS_INDIR`` binary Indir table bytes
``ETHTOOL_A_RSS_HKEY`` binary Hash key bytes
+ ``ETHTOOL_A_RSS_INPUT_XFRM`` u32 RSS input data transformation
===================================== ====== ==========================
ETHTOOL_A_RSS_HFUNC attribute is bitmap indicating the hash function
being used. Current supported options are toeplitz, xor or crc32.
-ETHTOOL_A_RSS_INDIR attribute returns RSS indrection table where each byte
+ETHTOOL_A_RSS_INDIR attribute returns RSS indirection table where each byte
indicates queue number.
+ETHTOOL_A_RSS_INPUT_XFRM attribute is a bitmap indicating the type of
+transformation applied to the input protocol fields before given to the RSS
+hfunc. Current supported option is symmetric-xor.
PLCA_GET_CFG
============
diff --git a/Documentation/networking/scaling.rst b/Documentation/networking/scaling.rst
index 03ae19a689fc..4eb50bcb9d42 100644
--- a/Documentation/networking/scaling.rst
+++ b/Documentation/networking/scaling.rst
@@ -44,6 +44,21 @@ by masking out the low order seven bits of the computed hash for the
packet (usually a Toeplitz hash), taking this number as a key into the
indirection table and reading the corresponding value.
+Some NICs support symmetric RSS hashing where, if the IP (source address,
+destination address) and TCP/UDP (source port, destination port) tuples
+are swapped, the computed hash is the same. This is beneficial in some
+applications that monitor TCP/IP flows (IDS, firewalls, ...etc) and need
+both directions of the flow to land on the same Rx queue (and CPU). The
+"Symmetric-XOR" is a type of RSS algorithms that achieves this hash
+symmetry by XORing the input source and destination fields of the IP
+and/or L4 protocols. This, however, results in reduced input entropy and
+could potentially be exploited. Specifically, the algorithm XORs the input
+as follows::
+
+ # (SRC_IP ^ DST_IP, SRC_IP ^ DST_IP, SRC_PORT ^ DST_PORT, SRC_PORT ^ DST_PORT)
+
+The result is then fed to the underlying RSS algorithm.
+
Some advanced NICs allow steering packets to queues based on
programmable filters. For example, webserver bound TCP port 80 packets
can be directed to their own receive queue. Such “n-tuple” filters can
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 66fe254c3e51..cfcd952a1d4f 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -615,6 +615,8 @@ struct ethtool_mm_stats {
* to allocate a new RSS context; on return this field will
* contain the ID of the newly allocated context.
* @rss_delete: Set to non-ZERO to remove the @rss_context context.
+ * @input_xfrm: Defines how the input data is transformed. Valid values are one
+ * of %RXH_XFRM_*.
*/
struct ethtool_rxfh_param {
u8 hfunc;
@@ -624,6 +626,7 @@ struct ethtool_rxfh_param {
u8 *key;
u32 rss_context;
u8 rss_delete;
+ u8 input_xfrm;
};
/**
@@ -632,6 +635,8 @@ struct ethtool_rxfh_param {
* parameter.
* @cap_rss_ctx_supported: indicates if the driver supports RSS
* contexts.
+ * @cap_rss_sym_xor_supported: indicates if the driver supports symmetric-xor
+ * RSS.
* @supported_coalesce_params: supported types of interrupt coalescing.
* @supported_ring_params: supported ring params.
* @get_drvinfo: Report driver/device information. Modern drivers no
@@ -811,6 +816,7 @@ struct ethtool_rxfh_param {
struct ethtool_ops {
u32 cap_link_lanes_supported:1;
u32 cap_rss_ctx_supported:1;
+ u32 cap_rss_sym_xor_supported:1;
u32 supported_coalesce_params;
u32 supported_ring_params;
void (*get_drvinfo)(struct net_device *, struct ethtool_drvinfo *);
diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index f7fba0dc87e5..0787d561ace0 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -1266,6 +1266,8 @@ struct ethtool_rxfh_indir {
* hardware hash key.
* @hfunc: Defines the current RSS hash function used by HW (or to be set to).
* Valid values are one of the %ETH_RSS_HASH_*.
+ * @input_xfrm: Defines how the input data is transformed. Valid values are one
+ * of %RXH_XFRM_*.
* @rsvd8: Reserved for future use; see the note on reserved space.
* @rsvd32: Reserved for future use; see the note on reserved space.
* @rss_config: RX ring/queue index for each hash value i.e., indirection table
@@ -1285,7 +1287,8 @@ struct ethtool_rxfh {
__u32 indir_size;
__u32 key_size;
__u8 hfunc;
- __u8 rsvd8[3];
+ __u8 input_xfrm;
+ __u8 rsvd8[2];
__u32 rsvd32;
__u32 rss_config[];
};
@@ -1992,6 +1995,14 @@ static inline int ethtool_validate_duplex(__u8 duplex)
#define WOL_MODE_COUNT 8
+/* RSS hash function data
+ * XOR the corresponding source and destination fields of each specified
+ * protocol. Both copies of the XOR'ed fields are fed into the RSS and RXHASH
+ * calculation. Note that this XORing reduces the input set entropy and could
+ * be exploited to reduce the RSS queue spread.
+ */
+#define RXH_XFRM_SYM_XOR (1 << 0)
+
/* L2-L4 network traffic flow types */
#define TCP_V4_FLOW 0x01 /* hash or spec (tcp_ip4_spec) */
#define UDP_V4_FLOW 0x02 /* hash or spec (udp_ip4_spec) */
diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index 73e2c10dc2cc..3f89074aa06c 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -908,6 +908,7 @@ enum {
ETHTOOL_A_RSS_HFUNC, /* u32 */
ETHTOOL_A_RSS_INDIR, /* binary */
ETHTOOL_A_RSS_HKEY, /* binary */
+ ETHTOOL_A_RSS_INPUT_XFRM, /* u32 */
__ETHTOOL_A_RSS_CNT,
ETHTOOL_A_RSS_MAX = (__ETHTOOL_A_RSS_CNT - 1),
diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c
index 86e5fc64b711..86d47425038b 100644
--- a/net/ethtool/ioctl.c
+++ b/net/ethtool/ioctl.c
@@ -972,18 +972,35 @@ static int ethtool_rxnfc_copy_to_user(void __user *useraddr,
static noinline_for_stack int ethtool_set_rxnfc(struct net_device *dev,
u32 cmd, void __user *useraddr)
{
+ const struct ethtool_ops *ops = dev->ethtool_ops;
+ struct ethtool_rxfh_param rxfh = {};
struct ethtool_rxnfc info;
size_t info_size = sizeof(info);
int rc;
- if (!dev->ethtool_ops->set_rxnfc)
+ if (!ops->set_rxnfc || !ops->get_rxfh)
return -EOPNOTSUPP;
rc = ethtool_rxnfc_copy_struct(cmd, &info, &info_size, useraddr);
if (rc)
return rc;
- rc = dev->ethtool_ops->set_rxnfc(dev, &info);
+ rc = ops->get_rxfh(dev, &rxfh);
+ if (rc)
+ return rc;
+
+ /* Sanity check: if symmetric-xor is set, then:
+ * 1 - no other fields besides IP src/dst and/or L4 src/dst
+ * 2 - If src is set, dst must also be set
+ */
+ if ((rxfh.input_xfrm & RXH_XFRM_SYM_XOR) &&
+ ((info.data & ~(RXH_IP_SRC | RXH_IP_DST |
+ RXH_L4_B_0_1 | RXH_L4_B_2_3)) ||
+ (!!(info.data & RXH_IP_SRC) ^ !!(info.data & RXH_IP_DST)) ||
+ (!!(info.data & RXH_L4_B_0_1) ^ !!(info.data & RXH_L4_B_2_3))))
+ return -EINVAL;
+
+ rc = ops->set_rxnfc(dev, &info);
if (rc)
return rc;
@@ -1198,7 +1215,7 @@ static noinline_for_stack int ethtool_get_rxfh(struct net_device *dev,
user_key_size = rxfh.key_size;
/* Check that reserved fields are 0 for now */
- if (rxfh.rsvd8[0] || rxfh.rsvd8[1] || rxfh.rsvd8[2] || rxfh.rsvd32)
+ if (rxfh.rsvd8[0] || rxfh.rsvd8[1] || rxfh.rsvd32)
return -EINVAL;
/* Most drivers don't handle rss_context, check it's 0 as well */
if (rxfh.rss_context && !ops->cap_rss_ctx_supported)
@@ -1271,11 +1288,15 @@ static noinline_for_stack int ethtool_set_rxfh(struct net_device *dev,
return -EFAULT;
/* Check that reserved fields are 0 for now */
- if (rxfh.rsvd8[0] || rxfh.rsvd8[1] || rxfh.rsvd8[2] || rxfh.rsvd32)
+ if (rxfh.rsvd8[0] || rxfh.rsvd8[1] || rxfh.rsvd32)
return -EINVAL;
/* Most drivers don't handle rss_context, check it's 0 as well */
if (rxfh.rss_context && !ops->cap_rss_ctx_supported)
return -EOPNOTSUPP;
+ /* Check input data transformation capabilities */
+ if ((rxfh.input_xfrm & RXH_XFRM_SYM_XOR) &&
+ !ops->cap_rss_sym_xor_supported)
+ return -EOPNOTSUPP;
/* If either indir, hash key or function is valid, proceed further.
* Must request at least one change: indir size, hash key or function.
@@ -1341,6 +1362,7 @@ static noinline_for_stack int ethtool_set_rxfh(struct net_device *dev,
rxfh_dev.hfunc = rxfh.hfunc;
rxfh_dev.rss_context = rxfh.rss_context;
+ rxfh_dev.input_xfrm = rxfh.input_xfrm;
ret = ops->set_rxfh(dev, &rxfh_dev, extack);
if (ret)
diff --git a/net/ethtool/rss.c b/net/ethtool/rss.c
index efc9f4409e40..71679137eff2 100644
--- a/net/ethtool/rss.c
+++ b/net/ethtool/rss.c
@@ -13,6 +13,7 @@ struct rss_reply_data {
u32 indir_size;
u32 hkey_size;
u32 hfunc;
+ u32 input_xfrm;
u32 *indir_table;
u8 *hkey;
};
@@ -97,6 +98,7 @@ rss_prepare_data(const struct ethnl_req_info *req_base,
goto out_ops;
data->hfunc = rxfh.hfunc;
+ data->input_xfrm = rxfh.input_xfrm;
out_ops:
ethnl_ops_complete(dev);
return ret;
@@ -110,6 +112,7 @@ rss_reply_size(const struct ethnl_req_info *req_base,
int len;
len = nla_total_size(sizeof(u32)) + /* _RSS_HFUNC */
+ nla_total_size(sizeof(u32)) + /* _RSS_INPUT_XFRM */
nla_total_size(sizeof(u32) * data->indir_size) + /* _RSS_INDIR */
nla_total_size(data->hkey_size); /* _RSS_HKEY */
@@ -124,6 +127,8 @@ rss_fill_reply(struct sk_buff *skb, const struct ethnl_req_info *req_base,
if ((data->hfunc &&
nla_put_u32(skb, ETHTOOL_A_RSS_HFUNC, data->hfunc)) ||
+ (data->input_xfrm &&
+ nla_put_u32(skb, ETHTOOL_A_RSS_INPUT_XFRM, data->input_xfrm)) ||
(data->indir_size &&
nla_put(skb, ETHTOOL_A_RSS_INDIR,
sizeof(u32) * data->indir_size, data->indir_table)) ||
generated by cgit (git 2.34.1) at 2024-06-02 20:32:13 +0000