[PATCH net-next v9 03/19] net: modify core data structures for PSP datapath support

[Daniel Zahka <daniel.zahka@gmail.com>]

From: Jakub Kicinski <kuba@kernel.org>

Add pointers to psp data structures to core networking structs,
and an SKB extension to carry the PSP information from the drivers
to the socket layer.

Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Co-developed-by: Daniel Zahka <daniel.zahka@gmail.com>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
---

Notes:
    v2:
    - Add dev_id field to psp_skb_ext
    - Move psp_assoc from struct tcp_timewait_sock to struct
      inet_timewait_sock
    - Move psp_sk_assoc_free() from sk_common_release() to
      inet_sock_destruct()
    v1:
      - https://lore.kernel.org/netdev/20240510030435.120935-4-kuba@kernel.org/

 include/linux/skbuff.h           | 3 +++
 include/net/inet_timewait_sock.h | 3 +++
 include/net/psp/functions.h      | 6 ++++++
 include/net/psp/types.h          | 7 +++++++
 include/net/sock.h               | 4 ++++
 net/core/skbuff.c                | 4 ++++
 net/ipv4/af_inet.c               | 2 ++
 net/ipv4/tcp_minisocks.c         | 2 ++
 8 files changed, 31 insertions(+)

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index ca8be45dd8be..4b77b856f025 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -4899,6 +4899,9 @@ enum skb_ext_id {
 #endif
 #if IS_ENABLED(CONFIG_MCTP_FLOWS)
 	SKB_EXT_MCTP,
+#endif
+#if IS_ENABLED(CONFIG_INET_PSP)
+	SKB_EXT_PSP,
 #endif
 	SKB_EXT_NUM, /* must be last */
 };
diff --git a/include/net/inet_timewait_sock.h b/include/net/inet_timewait_sock.h
index 67a313575780..c1295246216c 100644
--- a/include/net/inet_timewait_sock.h
+++ b/include/net/inet_timewait_sock.h
@@ -81,6 +81,9 @@ struct inet_timewait_sock {
 	struct timer_list	tw_timer;
 	struct inet_bind_bucket	*tw_tb;
 	struct inet_bind2_bucket	*tw_tb2;
+#if IS_ENABLED(CONFIG_INET_PSP)
+	struct psp_assoc __rcu	  *psp_assoc;
+#endif
 };
 #define tw_tclass tw_tos
 
diff --git a/include/net/psp/functions.h b/include/net/psp/functions.h
index 074f9df9afc3..d0043bd14299 100644
--- a/include/net/psp/functions.h
+++ b/include/net/psp/functions.h
@@ -5,10 +5,16 @@
 
 #include <net/psp/types.h>
 
+struct inet_timewait_sock;
+
 /* Driver-facing API */
 struct psp_dev *
 psp_dev_create(struct net_device *netdev, struct psp_dev_ops *psd_ops,
 	       struct psp_dev_caps *psd_caps, void *priv_ptr);
 void psp_dev_unregister(struct psp_dev *psd);
 
+/* Kernel-facing API */
+static inline void psp_sk_assoc_free(struct sock *sk) { }
+static inline void psp_twsk_assoc_free(struct inet_timewait_sock *tw) { }
+
 #endif /* __NET_PSP_HELPERS_H */
diff --git a/include/net/psp/types.h b/include/net/psp/types.h
index d242b1ecee7d..4922fc8d42fd 100644
--- a/include/net/psp/types.h
+++ b/include/net/psp/types.h
@@ -84,6 +84,13 @@ struct psp_dev_caps {
 
 #define PSP_MAX_KEY	32
 
+struct psp_skb_ext {
+	__be32 spi;
+	u16 dev_id;
+	u8 generation;
+	u8 version;
+};
+
 /**
  * struct psp_dev_ops - netdev driver facing PSP callbacks
  */
diff --git a/include/net/sock.h b/include/net/sock.h
index 63a6a48afb48..e589eef6ce0f 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -249,6 +249,7 @@ struct sk_filter;
   *	@sk_dst_cache: destination cache
   *	@sk_dst_pending_confirm: need to confirm neighbour
   *	@sk_policy: flow policy
+  *	@psp_assoc: PSP association, if socket is PSP-secured
   *	@sk_receive_queue: incoming packets
   *	@sk_wmem_alloc: transmit queue bytes committed
   *	@sk_tsq_flags: TCP Small Queues flags
@@ -448,6 +449,9 @@ struct sock {
 #endif
 #ifdef CONFIG_XFRM
 	struct xfrm_policy __rcu *sk_policy[2];
+#endif
+#if IS_ENABLED(CONFIG_INET_PSP)
+	struct psp_assoc __rcu	*psp_assoc;
 #endif
 	__cacheline_group_end(sock_read_rxtx);
 
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 23b776cd9879..d331e607edfb 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -79,6 +79,7 @@
 #include <net/mptcp.h>
 #include <net/mctp.h>
 #include <net/page_pool/helpers.h>
+#include <net/psp/types.h>
 #include <net/dropreason.h>
 
 #include <linux/uaccess.h>
@@ -5062,6 +5063,9 @@ static const u8 skb_ext_type_len[] = {
 #if IS_ENABLED(CONFIG_MCTP_FLOWS)
 	[SKB_EXT_MCTP] = SKB_EXT_CHUNKSIZEOF(struct mctp_flow),
 #endif
+#if IS_ENABLED(CONFIG_INET_PSP)
+	[SKB_EXT_PSP] = SKB_EXT_CHUNKSIZEOF(struct psp_skb_ext),
+#endif
 };
 
 static __always_inline unsigned int skb_ext_total_length(void)
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 76e38092cd8a..e298dacb4a06 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -102,6 +102,7 @@
 #include <net/gro.h>
 #include <net/gso.h>
 #include <net/tcp.h>
+#include <net/psp.h>
 #include <net/udp.h>
 #include <net/udplite.h>
 #include <net/ping.h>
@@ -158,6 +159,7 @@ void inet_sock_destruct(struct sock *sk)
 	kfree(rcu_dereference_protected(inet->inet_opt, 1));
 	dst_release(rcu_dereference_protected(sk->sk_dst_cache, 1));
 	dst_release(rcu_dereference_protected(sk->sk_rx_dst, 1));
+	psp_sk_assoc_free(sk);
 }
 EXPORT_SYMBOL(inet_sock_destruct);
 
diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c
index d1c9e4088646..17ecdbc66f05 100644
--- a/net/ipv4/tcp_minisocks.c
+++ b/net/ipv4/tcp_minisocks.c
@@ -23,6 +23,7 @@
 #include <net/xfrm.h>
 #include <net/busy_poll.h>
 #include <net/rstreason.h>
+#include <net/psp.h>
 
 static bool tcp_in_window(u32 seq, u32 end_seq, u32 s_win, u32 e_win)
 {
@@ -400,6 +401,7 @@ void tcp_twsk_destructor(struct sock *sk)
 	}
 #endif
 	tcp_ao_destroy_sock(sk, true);
+	psp_twsk_assoc_free(inet_twsk(sk));
 }
 
 void tcp_twsk_purge(struct list_head *net_exit_list)
-- 
2.47.3