Support for dissecting IPSEC field SPI (which is
32bits in size) for ESP and AH packets.
This implementation does not support NAT-T
(encapsulation of ESP packets over UDP).
Signed-off-by: Ratheesh Kannoth <[email protected]>
---
include/net/flow_dissector.h | 9 ++++++
include/net/flow_offload.h | 6 ++++
include/uapi/linux/pkt_cls.h | 3 ++
net/core/flow_dissector.c | 53 +++++++++++++++++++++++++++++++++++-
net/core/flow_offload.c | 7 +++++
net/sched/cls_flower.c | 18 ++++++++++++
6 files changed, 95 insertions(+), 1 deletion(-)
diff --git a/include/net/flow_dissector.h b/include/net/flow_dissector.h
index 8664ed4fbbdf..ffec739f049a 100644
--- a/include/net/flow_dissector.h
+++ b/include/net/flow_dissector.h
@@ -301,6 +301,14 @@ struct flow_dissector_key_l2tpv3 {
__be32 session_id;
};
+/**
+ * struct flow_dissector_key_ipsec:
+ * @spi: identifier for a ipsec connection
+ */
+struct flow_dissector_key_ipsec {
+ __be32 spi;
+};
+
/**
* struct flow_dissector_key_cfm
* @mdl_ver: maintenance domain level (mdl) and cfm protocol version
@@ -353,6 +361,7 @@ enum flow_dissector_key_id {
FLOW_DISSECTOR_KEY_NUM_OF_VLANS, /* struct flow_dissector_key_num_of_vlans */
FLOW_DISSECTOR_KEY_PPPOE, /* struct flow_dissector_key_pppoe */
FLOW_DISSECTOR_KEY_L2TPV3, /* struct flow_dissector_key_l2tpv3 */
+ FLOW_DISSECTOR_KEY_IPSEC, /* struct flow_dissector_key_ipsec */
FLOW_DISSECTOR_KEY_CFM, /* struct flow_dissector_key_cfm */
FLOW_DISSECTOR_KEY_MAX,
diff --git a/include/net/flow_offload.h b/include/net/flow_offload.h
index 118082eae48c..9efa9a59e81f 100644
--- a/include/net/flow_offload.h
+++ b/include/net/flow_offload.h
@@ -64,6 +64,10 @@ struct flow_match_tcp {
struct flow_dissector_key_tcp *key, *mask;
};
+struct flow_match_ipsec {
+ struct flow_dissector_key_ipsec *key, *mask;
+};
+
struct flow_match_mpls {
struct flow_dissector_key_mpls *key, *mask;
};
@@ -116,6 +120,8 @@ void flow_rule_match_ports_range(const struct flow_rule *rule,
struct flow_match_ports_range *out);
void flow_rule_match_tcp(const struct flow_rule *rule,
struct flow_match_tcp *out);
+void flow_rule_match_ipsec(const struct flow_rule *rule,
+ struct flow_match_ipsec *out);
void flow_rule_match_icmp(const struct flow_rule *rule,
struct flow_match_icmp *out);
void flow_rule_match_mpls(const struct flow_rule *rule,
diff --git a/include/uapi/linux/pkt_cls.h b/include/uapi/linux/pkt_cls.h
index 7865f5a9885b..a90b0e3d351f 100644
--- a/include/uapi/linux/pkt_cls.h
+++ b/include/uapi/linux/pkt_cls.h
@@ -594,6 +594,9 @@ enum {
TCA_FLOWER_KEY_L2TPV3_SID, /* be32 */
+ TCA_FLOWER_KEY_SPI, /* be32 */
+ TCA_FLOWER_KEY_SPI_MASK, /* be32 */
+
TCA_FLOWER_L2_MISS, /* u8 */
TCA_FLOWER_KEY_CFM, /* nested */
diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index 85a2d0d9bd39..7162594d7940 100644
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -205,6 +205,50 @@ static void __skb_flow_dissect_icmp(const struct sk_buff *skb,
skb_flow_get_icmp_tci(skb, key_icmp, data, thoff, hlen);
}
+static void __skb_flow_dissect_ah(const struct sk_buff *skb,
+ struct flow_dissector *flow_dissector,
+ void *target_container, const void *data,
+ int nhoff, int hlen)
+{
+ struct flow_dissector_key_ipsec *key_ah;
+ struct ip_auth_hdr _hdr, *hdr;
+
+ if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IPSEC))
+ return;
+
+ hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
+ if (!hdr)
+ return;
+
+ key_ah = skb_flow_dissector_target(flow_dissector,
+ FLOW_DISSECTOR_KEY_IPSEC,
+ target_container);
+
+ key_ah->spi = hdr->spi;
+}
+
+static void __skb_flow_dissect_esp(const struct sk_buff *skb,
+ struct flow_dissector *flow_dissector,
+ void *target_container, const void *data,
+ int nhoff, int hlen)
+{
+ struct flow_dissector_key_ipsec *key_esp;
+ struct ip_esp_hdr _hdr, *hdr;
+
+ if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IPSEC))
+ return;
+
+ hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
+ if (!hdr)
+ return;
+
+ key_esp = skb_flow_dissector_target(flow_dissector,
+ FLOW_DISSECTOR_KEY_IPSEC,
+ target_container);
+
+ key_esp->spi = hdr->spi;
+}
+
static void __skb_flow_dissect_l2tpv3(const struct sk_buff *skb,
struct flow_dissector *flow_dissector,
void *target_container, const void *data,
@@ -1571,7 +1615,14 @@ bool __skb_flow_dissect(const struct net *net,
__skb_flow_dissect_l2tpv3(skb, flow_dissector, target_container,
data, nhoff, hlen);
break;
-
+ case IPPROTO_ESP:
+ __skb_flow_dissect_esp(skb, flow_dissector, target_container,
+ data, nhoff, hlen);
+ break;
+ case IPPROTO_AH:
+ __skb_flow_dissect_ah(skb, flow_dissector, target_container,
+ data, nhoff, hlen);
+ break;
default:
break;
}
diff --git a/net/core/flow_offload.c b/net/core/flow_offload.c
index acfc1f88ea79..bc5169482710 100644
--- a/net/core/flow_offload.c
+++ b/net/core/flow_offload.c
@@ -146,6 +146,13 @@ void flow_rule_match_tcp(const struct flow_rule *rule,
}
EXPORT_SYMBOL(flow_rule_match_tcp);
+void flow_rule_match_ipsec(const struct flow_rule *rule,
+ struct flow_match_ipsec *out)
+{
+ FLOW_DISSECTOR_MATCH(rule, FLOW_DISSECTOR_KEY_IPSEC, out);
+}
+EXPORT_SYMBOL(flow_rule_match_ipsec);
+
void flow_rule_match_icmp(const struct flow_rule *rule,
struct flow_match_icmp *out)
{
diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c
index 8da9d039d964..7ba839057d3c 100644
--- a/net/sched/cls_flower.c
+++ b/net/sched/cls_flower.c
@@ -72,6 +72,7 @@ struct fl_flow_key {
struct flow_dissector_key_num_of_vlans num_of_vlans;
struct flow_dissector_key_pppoe pppoe;
struct flow_dissector_key_l2tpv3 l2tpv3;
+ struct flow_dissector_key_ipsec ipsec;
struct flow_dissector_key_cfm cfm;
} __aligned(BITS_PER_LONG / 8); /* Ensure that we can do comparisons as longs. */
@@ -726,6 +727,8 @@ static const struct nla_policy fl_policy[TCA_FLOWER_MAX + 1] = {
[TCA_FLOWER_KEY_PPPOE_SID] = { .type = NLA_U16 },
[TCA_FLOWER_KEY_PPP_PROTO] = { .type = NLA_U16 },
[TCA_FLOWER_KEY_L2TPV3_SID] = { .type = NLA_U32 },
+ [TCA_FLOWER_KEY_SPI] = { .type = NLA_U32 },
+ [TCA_FLOWER_KEY_SPI_MASK] = { .type = NLA_U32 },
[TCA_FLOWER_L2_MISS] = NLA_POLICY_MAX(NLA_U8, 1),
[TCA_FLOWER_KEY_CFM] = { .type = NLA_NESTED },
};
@@ -1894,6 +1897,13 @@ static int fl_set_key(struct net *net, struct nlattr **tb,
return ret;
}
+ if (tb[TCA_FLOWER_KEY_SPI]) {
+ fl_set_key_val(tb, &key->ipsec.spi,
+ TCA_FLOWER_KEY_SPI,
+ &mask->ipsec.spi, TCA_FLOWER_KEY_SPI_MASK,
+ sizeof(key->ipsec.spi));
+ }
+
if (tb[TCA_FLOWER_KEY_ENC_IPV4_SRC] ||
tb[TCA_FLOWER_KEY_ENC_IPV4_DST]) {
key->enc_control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
@@ -2066,6 +2076,8 @@ static void fl_init_dissector(struct flow_dissector *dissector,
FLOW_DISSECTOR_KEY_PPPOE, pppoe);
FL_KEY_SET_IF_MASKED(mask, keys, cnt,
FLOW_DISSECTOR_KEY_L2TPV3, l2tpv3);
+ FL_KEY_SET_IF_MASKED(mask, keys, cnt,
+ FLOW_DISSECTOR_KEY_IPSEC, ipsec);
FL_KEY_SET_IF_MASKED(mask, keys, cnt,
FLOW_DISSECTOR_KEY_CFM, cfm);
@@ -3364,6 +3376,12 @@ static int fl_dump_key(struct sk_buff *skb, struct net *net,
sizeof(key->l2tpv3.session_id)))
goto nla_put_failure;
+ if (key->ipsec.spi &&
+ fl_dump_key_val(skb, &key->ipsec.spi, TCA_FLOWER_KEY_SPI,
+ &mask->ipsec.spi, TCA_FLOWER_KEY_SPI_MASK,
+ sizeof(key->ipsec.spi)))
+ goto nla_put_failure;
+
if ((key->basic.ip_proto == IPPROTO_TCP ||
key->basic.ip_proto == IPPROTO_UDP ||
key->basic.ip_proto == IPPROTO_SCTP) &&
--
2.25.1
On Tue, Jul 25, 2023 at 08:54:51AM +0530, Ratheesh Kannoth wrote:
> Support for dissecting IPSEC field SPI (which is
> 32bits in size) for ESP and AH packets.
Please don't add extra space in the beginning of lines.
>
> This implementation does not support NAT-T
> (encapsulation of ESP packets over UDP).
And how will user distinguish kernel which supports flow_dissector with
NAT-T vs. without NAT-T?
>
> Signed-off-by: Ratheesh Kannoth <[email protected]>
> ---
> include/net/flow_dissector.h | 9 ++++++
> include/net/flow_offload.h | 6 ++++
> include/uapi/linux/pkt_cls.h | 3 ++
> net/core/flow_dissector.c | 53 +++++++++++++++++++++++++++++++++++-
> net/core/flow_offload.c | 7 +++++
> net/sched/cls_flower.c | 18 ++++++++++++
> 6 files changed, 95 insertions(+), 1 deletion(-)
>
> diff --git a/include/net/flow_dissector.h b/include/net/flow_dissector.h
> index 8664ed4fbbdf..ffec739f049a 100644
> --- a/include/net/flow_dissector.h
> +++ b/include/net/flow_dissector.h
> @@ -301,6 +301,14 @@ struct flow_dissector_key_l2tpv3 {
> __be32 session_id;
> };
>
> +/**
> + * struct flow_dissector_key_ipsec:
> + * @spi: identifier for a ipsec connection
> + */
> +struct flow_dissector_key_ipsec {
> + __be32 spi;
> +};
> +
> /**
> * struct flow_dissector_key_cfm
> * @mdl_ver: maintenance domain level (mdl) and cfm protocol version
> @@ -353,6 +361,7 @@ enum flow_dissector_key_id {
> FLOW_DISSECTOR_KEY_NUM_OF_VLANS, /* struct flow_dissector_key_num_of_vlans */
> FLOW_DISSECTOR_KEY_PPPOE, /* struct flow_dissector_key_pppoe */
> FLOW_DISSECTOR_KEY_L2TPV3, /* struct flow_dissector_key_l2tpv3 */
> + FLOW_DISSECTOR_KEY_IPSEC, /* struct flow_dissector_key_ipsec */
> FLOW_DISSECTOR_KEY_CFM, /* struct flow_dissector_key_cfm */
>
> FLOW_DISSECTOR_KEY_MAX,
> diff --git a/include/net/flow_offload.h b/include/net/flow_offload.h
> index 118082eae48c..9efa9a59e81f 100644
> --- a/include/net/flow_offload.h
> +++ b/include/net/flow_offload.h
> @@ -64,6 +64,10 @@ struct flow_match_tcp {
> struct flow_dissector_key_tcp *key, *mask;
> };
>
> +struct flow_match_ipsec {
> + struct flow_dissector_key_ipsec *key, *mask;
> +};
> +
> struct flow_match_mpls {
> struct flow_dissector_key_mpls *key, *mask;
> };
> @@ -116,6 +120,8 @@ void flow_rule_match_ports_range(const struct flow_rule *rule,
> struct flow_match_ports_range *out);
> void flow_rule_match_tcp(const struct flow_rule *rule,
> struct flow_match_tcp *out);
> +void flow_rule_match_ipsec(const struct flow_rule *rule,
> + struct flow_match_ipsec *out);
> void flow_rule_match_icmp(const struct flow_rule *rule,
> struct flow_match_icmp *out);
> void flow_rule_match_mpls(const struct flow_rule *rule,
> diff --git a/include/uapi/linux/pkt_cls.h b/include/uapi/linux/pkt_cls.h
> index 7865f5a9885b..a90b0e3d351f 100644
> --- a/include/uapi/linux/pkt_cls.h
> +++ b/include/uapi/linux/pkt_cls.h
> @@ -594,6 +594,9 @@ enum {
>
> TCA_FLOWER_KEY_L2TPV3_SID, /* be32 */
>
> + TCA_FLOWER_KEY_SPI, /* be32 */
> + TCA_FLOWER_KEY_SPI_MASK, /* be32 */
> +
> TCA_FLOWER_L2_MISS, /* u8 */
>
> TCA_FLOWER_KEY_CFM, /* nested */
> diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
> index 85a2d0d9bd39..7162594d7940 100644
> --- a/net/core/flow_dissector.c
> +++ b/net/core/flow_dissector.c
> @@ -205,6 +205,50 @@ static void __skb_flow_dissect_icmp(const struct sk_buff *skb,
> skb_flow_get_icmp_tci(skb, key_icmp, data, thoff, hlen);
> }
>
> +static void __skb_flow_dissect_ah(const struct sk_buff *skb,
> + struct flow_dissector *flow_dissector,
> + void *target_container, const void *data,
> + int nhoff, int hlen)
> +{
> + struct flow_dissector_key_ipsec *key_ah;
> + struct ip_auth_hdr _hdr, *hdr;
In tunnel mode, this struct is ip_esp_hdr and not ip_auth_hdr.
Thanks
> +
> + if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IPSEC))
> + return;
> +
> + hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
> + if (!hdr)
> + return;
> +
> + key_ah = skb_flow_dissector_target(flow_dissector,
> + FLOW_DISSECTOR_KEY_IPSEC,
> + target_container);
> +
> + key_ah->spi = hdr->spi;
> +}
> +
> +static void __skb_flow_dissect_esp(const struct sk_buff *skb,
> + struct flow_dissector *flow_dissector,
> + void *target_container, const void *data,
> + int nhoff, int hlen)
> +{
> + struct flow_dissector_key_ipsec *key_esp;
> + struct ip_esp_hdr _hdr, *hdr;
> +
> + if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IPSEC))
> + return;
> +
> + hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
> + if (!hdr)
> + return;
> +
> + key_esp = skb_flow_dissector_target(flow_dissector,
> + FLOW_DISSECTOR_KEY_IPSEC,
> + target_container);
> +
> + key_esp->spi = hdr->spi;
> +}
> +
> static void __skb_flow_dissect_l2tpv3(const struct sk_buff *skb,
> struct flow_dissector *flow_dissector,
> void *target_container, const void *data,
> @@ -1571,7 +1615,14 @@ bool __skb_flow_dissect(const struct net *net,
> __skb_flow_dissect_l2tpv3(skb, flow_dissector, target_container,
> data, nhoff, hlen);
> break;
> -
> + case IPPROTO_ESP:
> + __skb_flow_dissect_esp(skb, flow_dissector, target_container,
> + data, nhoff, hlen);
> + break;
> + case IPPROTO_AH:
> + __skb_flow_dissect_ah(skb, flow_dissector, target_container,
> + data, nhoff, hlen);
> + break;
> default:
> break;
> }
> diff --git a/net/core/flow_offload.c b/net/core/flow_offload.c
> index acfc1f88ea79..bc5169482710 100644
> --- a/net/core/flow_offload.c
> +++ b/net/core/flow_offload.c
> @@ -146,6 +146,13 @@ void flow_rule_match_tcp(const struct flow_rule *rule,
> }
> EXPORT_SYMBOL(flow_rule_match_tcp);
>
> +void flow_rule_match_ipsec(const struct flow_rule *rule,
> + struct flow_match_ipsec *out)
> +{
> + FLOW_DISSECTOR_MATCH(rule, FLOW_DISSECTOR_KEY_IPSEC, out);
> +}
> +EXPORT_SYMBOL(flow_rule_match_ipsec);
> +
> void flow_rule_match_icmp(const struct flow_rule *rule,
> struct flow_match_icmp *out)
> {
> diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c
> index 8da9d039d964..7ba839057d3c 100644
> --- a/net/sched/cls_flower.c
> +++ b/net/sched/cls_flower.c
> @@ -72,6 +72,7 @@ struct fl_flow_key {
> struct flow_dissector_key_num_of_vlans num_of_vlans;
> struct flow_dissector_key_pppoe pppoe;
> struct flow_dissector_key_l2tpv3 l2tpv3;
> + struct flow_dissector_key_ipsec ipsec;
> struct flow_dissector_key_cfm cfm;
> } __aligned(BITS_PER_LONG / 8); /* Ensure that we can do comparisons as longs. */
>
> @@ -726,6 +727,8 @@ static const struct nla_policy fl_policy[TCA_FLOWER_MAX + 1] = {
> [TCA_FLOWER_KEY_PPPOE_SID] = { .type = NLA_U16 },
> [TCA_FLOWER_KEY_PPP_PROTO] = { .type = NLA_U16 },
> [TCA_FLOWER_KEY_L2TPV3_SID] = { .type = NLA_U32 },
> + [TCA_FLOWER_KEY_SPI] = { .type = NLA_U32 },
> + [TCA_FLOWER_KEY_SPI_MASK] = { .type = NLA_U32 },
> [TCA_FLOWER_L2_MISS] = NLA_POLICY_MAX(NLA_U8, 1),
> [TCA_FLOWER_KEY_CFM] = { .type = NLA_NESTED },
> };
> @@ -1894,6 +1897,13 @@ static int fl_set_key(struct net *net, struct nlattr **tb,
> return ret;
> }
>
> + if (tb[TCA_FLOWER_KEY_SPI]) {
> + fl_set_key_val(tb, &key->ipsec.spi,
> + TCA_FLOWER_KEY_SPI,
> + &mask->ipsec.spi, TCA_FLOWER_KEY_SPI_MASK,
> + sizeof(key->ipsec.spi));
> + }
> +
> if (tb[TCA_FLOWER_KEY_ENC_IPV4_SRC] ||
> tb[TCA_FLOWER_KEY_ENC_IPV4_DST]) {
> key->enc_control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
> @@ -2066,6 +2076,8 @@ static void fl_init_dissector(struct flow_dissector *dissector,
> FLOW_DISSECTOR_KEY_PPPOE, pppoe);
> FL_KEY_SET_IF_MASKED(mask, keys, cnt,
> FLOW_DISSECTOR_KEY_L2TPV3, l2tpv3);
> + FL_KEY_SET_IF_MASKED(mask, keys, cnt,
> + FLOW_DISSECTOR_KEY_IPSEC, ipsec);
> FL_KEY_SET_IF_MASKED(mask, keys, cnt,
> FLOW_DISSECTOR_KEY_CFM, cfm);
>
> @@ -3364,6 +3376,12 @@ static int fl_dump_key(struct sk_buff *skb, struct net *net,
> sizeof(key->l2tpv3.session_id)))
> goto nla_put_failure;
>
> + if (key->ipsec.spi &&
> + fl_dump_key_val(skb, &key->ipsec.spi, TCA_FLOWER_KEY_SPI,
> + &mask->ipsec.spi, TCA_FLOWER_KEY_SPI_MASK,
> + sizeof(key->ipsec.spi)))
> + goto nla_put_failure;
> +
> if ((key->basic.ip_proto == IPPROTO_TCP ||
> key->basic.ip_proto == IPPROTO_UDP ||
> key->basic.ip_proto == IPPROTO_SCTP) &&
> --
> 2.25.1
>
>
On Tue, Jul 25, 2023 at 08:54:51AM +0530, Ratheesh Kannoth wrote:
> Support for dissecting IPSEC field SPI (which is
> 32bits in size) for ESP and AH packets.
>
> This implementation does not support NAT-T
> (encapsulation of ESP packets over UDP).
>
> Signed-off-by: Ratheesh Kannoth <[email protected]>
> ---
> include/net/flow_dissector.h | 9 ++++++
> include/net/flow_offload.h | 6 ++++
> include/uapi/linux/pkt_cls.h | 3 ++
> net/core/flow_dissector.c | 53 +++++++++++++++++++++++++++++++++++-
> net/core/flow_offload.c | 7 +++++
> net/sched/cls_flower.c | 18 ++++++++++++
Please split flow dissector and flower changes into separate patches.
Also, you can't add the flow offload bits without a corresponding driver
change. Nobody calls the exported flow_rule_match_ipsec() function.
[...]
> diff --git a/include/uapi/linux/pkt_cls.h b/include/uapi/linux/pkt_cls.h
> index 7865f5a9885b..a90b0e3d351f 100644
> --- a/include/uapi/linux/pkt_cls.h
> +++ b/include/uapi/linux/pkt_cls.h
> @@ -594,6 +594,9 @@ enum {
>
> TCA_FLOWER_KEY_L2TPV3_SID, /* be32 */
>
> + TCA_FLOWER_KEY_SPI, /* be32 */
> + TCA_FLOWER_KEY_SPI_MASK, /* be32 */
> +
This will break existing user space on new kernels. New attributes must
be added at the end.
> TCA_FLOWER_L2_MISS, /* u8 */
>
> TCA_FLOWER_KEY_CFM, /* nested */
On Tue, Jul 25, 2023 at 08:54:51AM +0530, Ratheesh Kannoth wrote:
...
> diff --git a/include/net/flow_dissector.h b/include/net/flow_dissector.h
> index 8664ed4fbbdf..ffec739f049a 100644
> --- a/include/net/flow_dissector.h
> +++ b/include/net/flow_dissector.h
> @@ -301,6 +301,14 @@ struct flow_dissector_key_l2tpv3 {
> __be32 session_id;
> };
>
> +/**
> + * struct flow_dissector_key_ipsec:
> + * @spi: identifier for a ipsec connection
> + */
> +struct flow_dissector_key_ipsec {
> + __be32 spi;
> +};
> +
> /**
> * struct flow_dissector_key_cfm
> * @mdl_ver: maintenance domain level (mdl) and cfm protocol version
> @@ -353,6 +361,7 @@ enum flow_dissector_key_id {
> FLOW_DISSECTOR_KEY_NUM_OF_VLANS, /* struct flow_dissector_key_num_of_vlans */
> FLOW_DISSECTOR_KEY_PPPOE, /* struct flow_dissector_key_pppoe */
> FLOW_DISSECTOR_KEY_L2TPV3, /* struct flow_dissector_key_l2tpv3 */
> + FLOW_DISSECTOR_KEY_IPSEC, /* struct flow_dissector_key_ipsec */
> FLOW_DISSECTOR_KEY_CFM, /* struct flow_dissector_key_cfm */
>
> FLOW_DISSECTOR_KEY_MAX,
...
Hi Ratheesh,
With this change, this enum now has 33 values, excluding
FLOW_DISSECTOR_KEY_MAX. I.e the range of values is from 0 to 32.
But dissector_uses_key() looks like this:
static inline bool dissector_uses_key(const struct flow_dissector *flow_dissector,
enum flow_dissector_key_id key_id)
{
return flow_dissector->used_keys & (1 << key_id);
}
And the type of the used_keys field of struct flow_dissector
is unsigned int, a 32bit entity.
So an overflow will now occur if key_id is FLOW_DISSECTOR_KEY_CFM.
This is flagged by Sparse.
--
pw-bot: changes-requested
> From: Leon Romanovsky <[email protected]>
> Subject: Re: [PATCH net-next] flow_dissector: Add IPSEC dissectors
> > Support for dissecting IPSEC field SPI (which is 32bits in size) for
> > ESP and AH packets.
>
> Please don't add extra space in the beginning of lines.
>
Ack.
> >
> > This implementation does not support NAT-T (encapsulation of ESP
> > packets over UDP).
>
> And how will user distinguish kernel which supports flow_dissector with
> NAT-T vs. without NAT-T?
Ack, will modify code to return error if ip protocol is neither ESP nor AH.
> >
> > Signed-off-by: Ratheesh Kannoth <[email protected]>
> > ---
> > include/net/flow_dissector.h | 9 ++++++
> > include/net/flow_offload.h | 6 ++++
> > include/uapi/linux/pkt_cls.h | 3 ++
> > net/core/flow_dissector.c | 53
> +++++++++++++++++++++++++++++++++++-
> > net/core/flow_offload.c | 7 +++++
> > net/sched/cls_flower.c | 18 ++++++++++++
> > 6 files changed, 95 insertions(+), 1 deletion(-)
> >
> > diff --git a/include/net/flow_dissector.h
> > b/include/net/flow_dissector.h index 8664ed4fbbdf..ffec739f049a 100644
> > --- a/include/net/flow_dissector.h
> > +++ b/include/net/flow_dissector.h
> > @@ -301,6 +301,14 @@ struct flow_dissector_key_l2tpv3 {
> > __be32 session_id;
> > };
> >
> > +/**
> > + * struct flow_dissector_key_ipsec:
> > + * @spi: identifier for a ipsec connection */ struct
> > +flow_dissector_key_ipsec {
> > + __be32 spi;
> > +};
> > +
> > /**
> > * struct flow_dissector_key_cfm
> > * @mdl_ver: maintenance domain level (mdl) and cfm protocol version
> > @@ -353,6 +361,7 @@ enum flow_dissector_key_id {
> > FLOW_DISSECTOR_KEY_NUM_OF_VLANS, /* struct
> flow_dissector_key_num_of_vlans */
> > FLOW_DISSECTOR_KEY_PPPOE, /* struct flow_dissector_key_pppoe
> */
> > FLOW_DISSECTOR_KEY_L2TPV3, /* struct flow_dissector_key_l2tpv3
> */
> > + FLOW_DISSECTOR_KEY_IPSEC, /* struct flow_dissector_key_ipsec */
> > FLOW_DISSECTOR_KEY_CFM, /* struct flow_dissector_key_cfm */
> >
> > FLOW_DISSECTOR_KEY_MAX,
> > diff --git a/include/net/flow_offload.h b/include/net/flow_offload.h
> > index 118082eae48c..9efa9a59e81f 100644
> > --- a/include/net/flow_offload.h
> > +++ b/include/net/flow_offload.h
> > @@ -64,6 +64,10 @@ struct flow_match_tcp {
> > struct flow_dissector_key_tcp *key, *mask; };
> >
> > +struct flow_match_ipsec {
> > + struct flow_dissector_key_ipsec *key, *mask; };
> > +
> > struct flow_match_mpls {
> > struct flow_dissector_key_mpls *key, *mask; }; @@ -116,6 +120,8
> @@
> > void flow_rule_match_ports_range(const struct flow_rule *rule,
> > struct flow_match_ports_range *out); void
> > flow_rule_match_tcp(const struct flow_rule *rule,
> > struct flow_match_tcp *out);
> > +void flow_rule_match_ipsec(const struct flow_rule *rule,
> > + struct flow_match_ipsec *out);
> > void flow_rule_match_icmp(const struct flow_rule *rule,
> > struct flow_match_icmp *out);
> > void flow_rule_match_mpls(const struct flow_rule *rule, diff --git
> > a/include/uapi/linux/pkt_cls.h b/include/uapi/linux/pkt_cls.h index
> > 7865f5a9885b..a90b0e3d351f 100644
> > --- a/include/uapi/linux/pkt_cls.h
> > +++ b/include/uapi/linux/pkt_cls.h
> > @@ -594,6 +594,9 @@ enum {
> >
> > TCA_FLOWER_KEY_L2TPV3_SID, /* be32 */
> >
> > + TCA_FLOWER_KEY_SPI, /* be32 */
> > + TCA_FLOWER_KEY_SPI_MASK, /* be32 */
> > +
> > TCA_FLOWER_L2_MISS, /* u8 */
> >
> > TCA_FLOWER_KEY_CFM, /* nested */
> > diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
> > index 85a2d0d9bd39..7162594d7940 100644
> > --- a/net/core/flow_dissector.c
> > +++ b/net/core/flow_dissector.c
> > @@ -205,6 +205,50 @@ static void __skb_flow_dissect_icmp(const struct
> sk_buff *skb,
> > skb_flow_get_icmp_tci(skb, key_icmp, data, thoff, hlen); }
> >
> > +static void __skb_flow_dissect_ah(const struct sk_buff *skb,
> > + struct flow_dissector *flow_dissector,
> > + void *target_container, const void *data,
> > + int nhoff, int hlen)
> > +{
> > + struct flow_dissector_key_ipsec *key_ah;
> > + struct ip_auth_hdr _hdr, *hdr;
>
> In tunnel mode, this struct is ip_esp_hdr and not ip_auth_hdr.
>
> Thanks
>
> > +
> > + if (!dissector_uses_key(flow_dissector,
> FLOW_DISSECTOR_KEY_IPSEC))
> > + return;
> > +
> > + hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen,
> &_hdr);
> > + if (!hdr)
> > + return;
> > +
> > + key_ah = skb_flow_dissector_target(flow_dissector,
> > + FLOW_DISSECTOR_KEY_IPSEC,
> > + target_container);
> > +
> > + key_ah->spi = hdr->spi;
> > +}
> > +
> > +static void __skb_flow_dissect_esp(const struct sk_buff *skb,
> > + struct flow_dissector *flow_dissector,
> > + void *target_container, const void *data,
> > + int nhoff, int hlen)
> > +{
> > + struct flow_dissector_key_ipsec *key_esp;
> > + struct ip_esp_hdr _hdr, *hdr;
> > +
> > + if (!dissector_uses_key(flow_dissector,
> FLOW_DISSECTOR_KEY_IPSEC))
> > + return;
> > +
> > + hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen,
> &_hdr);
> > + if (!hdr)
> > + return;
> > +
> > + key_esp = skb_flow_dissector_target(flow_dissector,
> > + FLOW_DISSECTOR_KEY_IPSEC,
> > + target_container);
> > +
> > + key_esp->spi = hdr->spi;
> > +}
> > +
> > static void __skb_flow_dissect_l2tpv3(const struct sk_buff *skb,
> > struct flow_dissector *flow_dissector,
> > void *target_container, const void *data,
> @@ -1571,7
> > +1615,14 @@ bool __skb_flow_dissect(const struct net *net,
> > __skb_flow_dissect_l2tpv3(skb, flow_dissector,
> target_container,
> > data, nhoff, hlen);
> > break;
> > -
> > + case IPPROTO_ESP:
> > + __skb_flow_dissect_esp(skb, flow_dissector,
> target_container,
> > + data, nhoff, hlen);
> > + break;
> > + case IPPROTO_AH:
> > + __skb_flow_dissect_ah(skb, flow_dissector,
> target_container,
> > + data, nhoff, hlen);
> > + break;
> > default:
> > break;
> > }
> > diff --git a/net/core/flow_offload.c b/net/core/flow_offload.c index
> > acfc1f88ea79..bc5169482710 100644
> > --- a/net/core/flow_offload.c
> > +++ b/net/core/flow_offload.c
> > @@ -146,6 +146,13 @@ void flow_rule_match_tcp(const struct flow_rule
> > *rule, } EXPORT_SYMBOL(flow_rule_match_tcp);
> >
> > +void flow_rule_match_ipsec(const struct flow_rule *rule,
> > + struct flow_match_ipsec *out)
> > +{
> > + FLOW_DISSECTOR_MATCH(rule, FLOW_DISSECTOR_KEY_IPSEC, out);
> }
> > +EXPORT_SYMBOL(flow_rule_match_ipsec);
> > +
> > void flow_rule_match_icmp(const struct flow_rule *rule,
> > struct flow_match_icmp *out)
> > {
> > diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c index
> > 8da9d039d964..7ba839057d3c 100644
> > --- a/net/sched/cls_flower.c
> > +++ b/net/sched/cls_flower.c
> > @@ -72,6 +72,7 @@ struct fl_flow_key {
> > struct flow_dissector_key_num_of_vlans num_of_vlans;
> > struct flow_dissector_key_pppoe pppoe;
> > struct flow_dissector_key_l2tpv3 l2tpv3;
> > + struct flow_dissector_key_ipsec ipsec;
> > struct flow_dissector_key_cfm cfm;
> > } __aligned(BITS_PER_LONG / 8); /* Ensure that we can do comparisons
> > as longs. */
> >
> > @@ -726,6 +727,8 @@ static const struct nla_policy
> fl_policy[TCA_FLOWER_MAX + 1] = {
> > [TCA_FLOWER_KEY_PPPOE_SID] = { .type = NLA_U16 },
> > [TCA_FLOWER_KEY_PPP_PROTO] = { .type = NLA_U16 },
> > [TCA_FLOWER_KEY_L2TPV3_SID] = { .type = NLA_U32 },
> > + [TCA_FLOWER_KEY_SPI] = { .type = NLA_U32 },
> > + [TCA_FLOWER_KEY_SPI_MASK] = { .type = NLA_U32 },
> > [TCA_FLOWER_L2_MISS] =
> NLA_POLICY_MAX(NLA_U8, 1),
> > [TCA_FLOWER_KEY_CFM] = { .type = NLA_NESTED },
> > };
> > @@ -1894,6 +1897,13 @@ static int fl_set_key(struct net *net, struct nlattr
> **tb,
> > return ret;
> > }
> >
> > + if (tb[TCA_FLOWER_KEY_SPI]) {
> > + fl_set_key_val(tb, &key->ipsec.spi,
> > + TCA_FLOWER_KEY_SPI,
> > + &mask->ipsec.spi, TCA_FLOWER_KEY_SPI_MASK,
> > + sizeof(key->ipsec.spi));
> > + }
> > +
> > if (tb[TCA_FLOWER_KEY_ENC_IPV4_SRC] ||
> > tb[TCA_FLOWER_KEY_ENC_IPV4_DST]) {
> > key->enc_control.addr_type =
> FLOW_DISSECTOR_KEY_IPV4_ADDRS; @@
> > -2066,6 +2076,8 @@ static void fl_init_dissector(struct flow_dissector
> *dissector,
> > FLOW_DISSECTOR_KEY_PPPOE, pppoe);
> > FL_KEY_SET_IF_MASKED(mask, keys, cnt,
> > FLOW_DISSECTOR_KEY_L2TPV3, l2tpv3);
> > + FL_KEY_SET_IF_MASKED(mask, keys, cnt,
> > + FLOW_DISSECTOR_KEY_IPSEC, ipsec);
> > FL_KEY_SET_IF_MASKED(mask, keys, cnt,
> > FLOW_DISSECTOR_KEY_CFM, cfm);
> >
> > @@ -3364,6 +3376,12 @@ static int fl_dump_key(struct sk_buff *skb,
> struct net *net,
> > sizeof(key->l2tpv3.session_id)))
> > goto nla_put_failure;
> >
> > + if (key->ipsec.spi &&
> > + fl_dump_key_val(skb, &key->ipsec.spi, TCA_FLOWER_KEY_SPI,
> > + &mask->ipsec.spi, TCA_FLOWER_KEY_SPI_MASK,
> > + sizeof(key->ipsec.spi)))
> > + goto nla_put_failure;
> > +
> > if ((key->basic.ip_proto == IPPROTO_TCP ||
> > key->basic.ip_proto == IPPROTO_UDP ||
> > key->basic.ip_proto == IPPROTO_SCTP) &&
> > --
> > 2.25.1
> >
> >
> From: Ido Schimmel <[email protected]>
> Sent: Tuesday, July 25, 2023 3:43 PM
> Subject: [EXT] Re: [PATCH net-next] flow_dissector: Add IPSEC dissectors
> > include/net/flow_dissector.h | 9 ++++++
> > include/net/flow_offload.h | 6 ++++
> > include/uapi/linux/pkt_cls.h | 3 ++
> > net/core/flow_dissector.c | 53
> +++++++++++++++++++++++++++++++++++-
> > net/core/flow_offload.c | 7 +++++
> > net/sched/cls_flower.c | 18 ++++++++++++
>
> Please split flow dissector and flower changes into separate patches.
> Also, you can't add the flow offload bits without a corresponding driver
> change. Nobody calls the exported flow_rule_match_ipsec() function.
>
Ack, will remove offload related code from this patch.
> [...]
>
> > diff --git a/include/uapi/linux/pkt_cls.h
> > b/include/uapi/linux/pkt_cls.h index 7865f5a9885b..a90b0e3d351f 100644
> > --- a/include/uapi/linux/pkt_cls.h
> > +++ b/include/uapi/linux/pkt_cls.h
> > @@ -594,6 +594,9 @@ enum {
> >
> > TCA_FLOWER_KEY_L2TPV3_SID, /* be32 */
> >
> > + TCA_FLOWER_KEY_SPI, /* be32 */
> > + TCA_FLOWER_KEY_SPI_MASK, /* be32 */
> > +
>
> This will break existing user space on new kernels. New attributes must be
> added at the end.
>
> > TCA_FLOWER_L2_MISS, /* u8 */
> >
> > TCA_FLOWER_KEY_CFM, /* nested */
> From: Simon Horman <[email protected]>
> Sent: Wednesday, July 26, 2023 1:21 AM
> Subject: [EXT] Re: [PATCH net-next] flow_dissector: Add IPSEC dissectors
> > FLOW_DISSECTOR_KEY_NUM_OF_VLANS, /* struct
> flow_dissector_key_num_of_vlans */
> > FLOW_DISSECTOR_KEY_PPPOE, /* struct flow_dissector_key_pppoe
> */
> > FLOW_DISSECTOR_KEY_L2TPV3, /* struct flow_dissector_key_l2tpv3
> */
> > + FLOW_DISSECTOR_KEY_IPSEC, /* struct flow_dissector_key_ipsec */
> > FLOW_DISSECTOR_KEY_CFM, /* struct flow_dissector_key_cfm */
> >
> > FLOW_DISSECTOR_KEY_MAX,
>
> ...
>
> Hi Ratheesh,
>
> With this change, this enum now has 33 values, excluding
> FLOW_DISSECTOR_KEY_MAX. I.e the range of values is from 0 to 32.
>
> But dissector_uses_key() looks like this:
>
>
> static inline bool dissector_uses_key(const struct flow_dissector
> *flow_dissector,
> enum flow_dissector_key_id key_id) {
> return flow_dissector->used_keys & (1 << key_id); }
>
> And the type of the used_keys field of struct flow_dissector is unsigned int, a
> 32bit entity.
>
> So an overflow will now occur if key_id is FLOW_DISSECTOR_KEY_CFM.
>
> This is flagged by Sparse.
>
Thank you !
1) How did you run sparse to detect this error. When I ran below command, it did not throw this error/warning ?
make C=2 net/core/ V=s
sparse version is 0.6.4
2) Is it okay to change variable type of "used_keys" from "unsigned int" to "unsigned long long" to accommodate this.
This variable is used at lot of places in the code.
-Ratheesh
> --
> pw-bot: changes-requested
On Wed, Jul 26, 2023 at 06:34:34AM +0000, Ratheesh Kannoth wrote:
> > From: Simon Horman <[email protected]>
> > Sent: Wednesday, July 26, 2023 1:21 AM
> > Subject: [EXT] Re: [PATCH net-next] flow_dissector: Add IPSEC dissectors
>
>
> > > FLOW_DISSECTOR_KEY_NUM_OF_VLANS, /* struct
> > flow_dissector_key_num_of_vlans */
> > > FLOW_DISSECTOR_KEY_PPPOE, /* struct flow_dissector_key_pppoe
> > */
> > > FLOW_DISSECTOR_KEY_L2TPV3, /* struct flow_dissector_key_l2tpv3
> > */
> > > + FLOW_DISSECTOR_KEY_IPSEC, /* struct flow_dissector_key_ipsec */
> > > FLOW_DISSECTOR_KEY_CFM, /* struct flow_dissector_key_cfm */
> > >
> > > FLOW_DISSECTOR_KEY_MAX,
> >
> > ...
> >
> > Hi Ratheesh,
> >
> > With this change, this enum now has 33 values, excluding
> > FLOW_DISSECTOR_KEY_MAX. I.e the range of values is from 0 to 32.
> >
> > But dissector_uses_key() looks like this:
> >
> >
> > static inline bool dissector_uses_key(const struct flow_dissector
> > *flow_dissector,
> > enum flow_dissector_key_id key_id) {
> > return flow_dissector->used_keys & (1 << key_id); }
> >
> > And the type of the used_keys field of struct flow_dissector is unsigned int, a
> > 32bit entity.
> >
> > So an overflow will now occur if key_id is FLOW_DISSECTOR_KEY_CFM.
> >
> > This is flagged by Sparse.
> >
Hi Ratheesh,
> Thank you !
> 1) How did you run sparse to detect this error. When I ran below command, it did not throw this error/warning ?
> make C=2 net/core/ V=s
I ran:
make C=2 net/core/flow_dissector.o
FWIIW, I also saw the warning using make C=2 net/core/ V=s
> sparse version is 0.6.4
I am using sparse git commit ce1a6720f69e, because at one point that
was the newest revision at a time the packaged version I had wasn't working
for me, and that was the latest commit at the time.
https://git.kernel.org/pub/scm/devel/sparse/sparse.git/commit/ce1a6720f69e
> 2) Is it okay to change variable type of "used_keys" from "unsigned int" to "unsigned long long" to accommodate this.
> This variable is used at lot of places in the code.
I might go for u64.
But yes, I suspect making the variable wider is a viable solution.
Given that it is widely used it would be good to inspect
how it is used to make sure this change makes sense.
I would make this change a separate patch if it is more than one line.
Also, while you are there, can you fix the spelling mistake in
the comment on the 'used_keys' line in struct flow_dissector ?
It's the same line that needs to be changed to change the type of 'used_keys'.