Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next

Steffen Klassert says:

====================
1) Refactor selftests to use an array of structs in xfrm_fill_key().
   From Gautam Menghani.

2) Drop an unused argument from xfrm_policy_match.
   From Hongbin Wang.

3) Support collect metadata mode for xfrm interfaces.
   From Eyal Birger.

4) Add netlink extack support to xfrm.
   From Sabrina Dubroca.

Please note, there is a merge conflict in:

include/net/dst_metadata.h

between commit:

0a28bfd4 ("net/macsec: Add MACsec skb_metadata_dst Tx Data path support")

from the net-next tree and commit:

5182a5d4 ("net: allow storing xfrm interface metadata in metadata_dst")

from the ipsec-next tree.

Can be solved as done in linux-next.

Please pull or let me know if there are problems.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/dst_metadata.h

@@ -11,6 +11,7 @@ enum metadata_type {
 	METADATA_IP_TUNNEL,
 	METADATA_HW_PORT_MUX,
 	METADATA_MACSEC,
+	METADATA_XFRM,
 };
 
 struct hw_port_info {
@@ -22,6 +23,11 @@ struct macsec_info {
 	sci_t sci;
 };
 
+struct xfrm_md_info {
+	u32 if_id;
+	int link;
+};
+
 struct metadata_dst {
 	struct dst_entry		dst;
 	enum metadata_type		type;
@@ -29,6 +35,7 @@ struct metadata_dst {
 		struct ip_tunnel_info	tun_info;
 		struct hw_port_info	port_info;
 		struct macsec_info	macsec_info;
+		struct xfrm_md_info	xfrm_info;
 	} u;
 };
 
@@ -60,6 +67,27 @@ skb_tunnel_info(const struct sk_buff *skb)
 	return NULL;
 }
 
+static inline struct xfrm_md_info *lwt_xfrm_info(struct lwtunnel_state *lwt)
+{
+	return (struct xfrm_md_info *)lwt->data;
+}
+
+static inline struct xfrm_md_info *skb_xfrm_md_info(const struct sk_buff *skb)
+{
+	struct metadata_dst *md_dst = skb_metadata_dst(skb);
+	struct dst_entry *dst;
+
+	if (md_dst && md_dst->type == METADATA_XFRM)
+		return &md_dst->u.xfrm_info;
+
+	dst = skb_dst(skb);
+	if (dst && dst->lwtstate &&
+	    dst->lwtstate->type == LWTUNNEL_ENCAP_XFRM)
+		return lwt_xfrm_info(dst->lwtstate);
+
+	return NULL;
+}
+
 static inline bool skb_valid_dst(const struct sk_buff *skb)
 {
 	struct dst_entry *dst = skb_dst(skb);
@@ -92,6 +120,9 @@ static inline int skb_metadata_dst_cmp(const struct sk_buff *skb_a,
 	case METADATA_MACSEC:
 		return memcmp(&a->u.macsec_info, &b->u.macsec_info,
 			      sizeof(a->u.macsec_info));
+	case METADATA_XFRM:
+		return memcmp(&a->u.xfrm_info, &b->u.xfrm_info,
+			      sizeof(a->u.xfrm_info));
 	default:
 		return 1;
 	}

include/net/ipcomp.h

@@ -22,7 +22,7 @@ struct xfrm_state;
 int ipcomp_input(struct xfrm_state *x, struct sk_buff *skb);
 int ipcomp_output(struct xfrm_state *x, struct sk_buff *skb);
 void ipcomp_destroy(struct xfrm_state *x);
-int ipcomp_init_state(struct xfrm_state *x);
+int ipcomp_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack);
 
 static inline struct ip_comp_hdr *ip_comp_hdr(const struct sk_buff *skb)
 {

include/net/xfrm.h

@@ -312,9 +312,15 @@ struct km_event {
 	struct net *net;
 };
 
+struct xfrm_if_decode_session_result {
+	struct net *net;
+	u32 if_id;
+};
+
 struct xfrm_if_cb {
-	struct xfrm_if	*(*decode_session)(struct sk_buff *skb,
-					   unsigned short family);
+	bool (*decode_session)(struct sk_buff *skb,
+			       unsigned short family,
+			       struct xfrm_if_decode_session_result *res);
 };
 
 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb);
@@ -399,7 +405,8 @@ struct xfrm_type {
 #define XFRM_TYPE_LOCAL_COADDR	4
 #define XFRM_TYPE_REMOTE_COADDR	8
 
-	int			(*init_state)(struct xfrm_state *x);
+	int			(*init_state)(struct xfrm_state *x,
+					      struct netlink_ext_ack *extack);
 	void			(*destructor)(struct xfrm_state *);
 	int			(*input)(struct xfrm_state *, struct sk_buff *skb);
 	int			(*output)(struct xfrm_state *, struct sk_buff *pskb);
@@ -985,6 +992,7 @@ void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev);
 struct xfrm_if_parms {
 	int link;		/* ifindex of underlying L2 interface */
 	u32 if_id;		/* interface identifyer */
+	bool collect_md;
 };
 
 struct xfrm_if {
@@ -1573,9 +1581,10 @@ int xfrm_dev_state_flush(struct net *net, struct net_device *dev, bool task_vali
 void xfrm_sad_getinfo(struct net *net, struct xfrmk_sadinfo *si);
 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si);
 u32 xfrm_replay_seqhi(struct xfrm_state *x, __be32 net_seq);
-int xfrm_init_replay(struct xfrm_state *x);
+int xfrm_init_replay(struct xfrm_state *x, struct netlink_ext_ack *extack);
 u32 xfrm_state_mtu(struct xfrm_state *x, int mtu);
-int __xfrm_init_state(struct xfrm_state *x, bool init_replay, bool offload);
+int __xfrm_init_state(struct xfrm_state *x, bool init_replay, bool offload,
+		      struct netlink_ext_ack *extack);
 int xfrm_init_state(struct xfrm_state *x);
 int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type);
 int xfrm_input_resume(struct sk_buff *skb, int nexthdr);
@@ -1879,7 +1888,8 @@ void xfrm_dev_resume(struct sk_buff *skb);
 void xfrm_dev_backlog(struct softnet_data *sd);
 struct sk_buff *validate_xmit_xfrm(struct sk_buff *skb, netdev_features_t features, bool *again);
 int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
-		       struct xfrm_user_offload *xuo);
+		       struct xfrm_user_offload *xuo,
+		       struct netlink_ext_ack *extack);
 bool xfrm_dev_offload_ok(struct sk_buff *skb, struct xfrm_state *x);
 
 static inline void xfrm_dev_state_advance_esn(struct xfrm_state *x)
@@ -1942,7 +1952,7 @@ static inline struct sk_buff *validate_xmit_xfrm(struct sk_buff *skb, netdev_fea
 	return skb;
 }
 
-static inline int xfrm_dev_state_add(struct net *net, struct xfrm_state *x, struct xfrm_user_offload *xuo)
+static inline int xfrm_dev_state_add(struct net *net, struct xfrm_state *x, struct xfrm_user_offload *xuo, struct netlink_ext_ack *extack)
 {
 	return 0;
 }

include/uapi/linux/if_link.h

@@ -695,6 +695,7 @@ enum {
 	IFLA_XFRM_UNSPEC,
 	IFLA_XFRM_LINK,
 	IFLA_XFRM_IF_ID,
+	IFLA_XFRM_COLLECT_METADATA,
 	__IFLA_XFRM_MAX
 };
 

include/uapi/linux/lwtunnel.h

@@ -15,6 +15,7 @@ enum lwtunnel_encap_types {
 	LWTUNNEL_ENCAP_SEG6_LOCAL,
 	LWTUNNEL_ENCAP_RPL,
 	LWTUNNEL_ENCAP_IOAM6,
+	LWTUNNEL_ENCAP_XFRM,
 	__LWTUNNEL_ENCAP_MAX,
 };
 
@@ -111,4 +112,13 @@ enum {
 
 #define LWT_BPF_MAX_HEADROOM 256
 
+enum {
+	LWT_XFRM_UNSPEC,
+	LWT_XFRM_IF_ID,
+	LWT_XFRM_LINK,
+	__LWT_XFRM_MAX,
+};
+
+#define LWT_XFRM_MAX (__LWT_XFRM_MAX - 1)
+
 #endif /* _UAPI_LWTUNNEL_H_ */

net/core/lwtunnel.c

@@ -50,6 +50,7 @@ static const char *lwtunnel_encap_str(enum lwtunnel_encap_types encap_type)
 		return "IOAM6";
 	case LWTUNNEL_ENCAP_IP6:
 	case LWTUNNEL_ENCAP_IP:
+	case LWTUNNEL_ENCAP_XFRM:
 	case LWTUNNEL_ENCAP_NONE:
 	case __LWTUNNEL_ENCAP_MAX:
 		/* should not have got here */

net/ipv4/ah4.c

@@ -471,30 +471,38 @@ static int ah4_err(struct sk_buff *skb, u32 info)
 	return 0;
 }
 
-static int ah_init_state(struct xfrm_state *x)
+static int ah_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	struct ah_data *ahp = NULL;
 	struct xfrm_algo_desc *aalg_desc;
 	struct crypto_ahash *ahash;
 
-	if (!x->aalg)
+	if (!x->aalg) {
+		NL_SET_ERR_MSG(extack, "AH requires a state with an AUTH algorithm");
 		goto error;
+	}
 
-	if (x->encap)
+	if (x->encap) {
+		NL_SET_ERR_MSG(extack, "AH is not compatible with encapsulation");
 		goto error;
+	}
 
 	ahp = kzalloc(sizeof(*ahp), GFP_KERNEL);
 	if (!ahp)
 		return -ENOMEM;
 
 	ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0);
-	if (IS_ERR(ahash))
+	if (IS_ERR(ahash)) {
+		NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 		goto error;
+	}
 
 	ahp->ahash = ahash;
 	if (crypto_ahash_setkey(ahash, x->aalg->alg_key,
-				(x->aalg->alg_key_len + 7) / 8))
+				(x->aalg->alg_key_len + 7) / 8)) {
+		NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 		goto error;
+	}
 
 	/*
 	 * Lookup the algorithm description maintained by xfrm_algo,
@@ -507,10 +515,7 @@ static int ah_init_state(struct xfrm_state *x)
 
 	if (aalg_desc->uinfo.auth.icv_fullbits/8 !=
 	    crypto_ahash_digestsize(ahash)) {
-		pr_info("%s: %s digestsize %u != %u\n",
-			__func__, x->aalg->alg_name,
-			crypto_ahash_digestsize(ahash),
-			aalg_desc->uinfo.auth.icv_fullbits / 8);
+		NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 		goto error;
 	}
 

net/ipv4/esp4.c

@@ -1008,16 +1008,17 @@ static void esp_destroy(struct xfrm_state *x)
 	crypto_free_aead(aead);
 }
 
-static int esp_init_aead(struct xfrm_state *x)
+static int esp_init_aead(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	char aead_name[CRYPTO_MAX_ALG_NAME];
 	struct crypto_aead *aead;
 	int err;
 
-	err = -ENAMETOOLONG;
 	if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
-		     x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME)
-		goto error;
+		     x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME) {
+		NL_SET_ERR_MSG(extack, "Algorithm name is too long");
+		return -ENAMETOOLONG;
+	}
 
 	aead = crypto_alloc_aead(aead_name, 0, 0);
 	err = PTR_ERR(aead);
@@ -1035,11 +1036,15 @@ static int esp_init_aead(struct xfrm_state *x)
 	if (err)
 		goto error;
 
+	return 0;
+
 error:
+	NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 	return err;
 }
 
-static int esp_init_authenc(struct xfrm_state *x)
+static int esp_init_authenc(struct xfrm_state *x,
+			    struct netlink_ext_ack *extack)
 {
 	struct crypto_aead *aead;
 	struct crypto_authenc_key_param *param;
@@ -1050,10 +1055,6 @@ static int esp_init_authenc(struct xfrm_state *x)
 	unsigned int keylen;
 	int err;
 
-	err = -EINVAL;
-	if (!x->ealg)
-		goto error;
-
 	err = -ENAMETOOLONG;
 
 	if ((x->props.flags & XFRM_STATE_ESN)) {
@@ -1062,22 +1063,28 @@ static int esp_init_authenc(struct xfrm_state *x)
 			     x->geniv ?: "", x->geniv ? "(" : "",
 			     x->aalg ? x->aalg->alg_name : "digest_null",
 			     x->ealg->alg_name,
-			     x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME)
+			     x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) {
+			NL_SET_ERR_MSG(extack, "Algorithm name is too long");
 			goto error;
+		}
 	} else {
 		if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME,
 			     "%s%sauthenc(%s,%s)%s",
 			     x->geniv ?: "", x->geniv ? "(" : "",
 			     x->aalg ? x->aalg->alg_name : "digest_null",
 			     x->ealg->alg_name,
-			     x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME)
+			     x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) {
+			NL_SET_ERR_MSG(extack, "Algorithm name is too long");
 			goto error;
 		}
+	}
 
 	aead = crypto_alloc_aead(authenc_name, 0, 0);
 	err = PTR_ERR(aead);
-	if (IS_ERR(aead))
+	if (IS_ERR(aead)) {
+		NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 		goto error;
+	}
 
 	x->data = aead;
 
@@ -1107,18 +1114,17 @@ static int esp_init_authenc(struct xfrm_state *x)
 		err = -EINVAL;
 		if (aalg_desc->uinfo.auth.icv_fullbits / 8 !=
 		    crypto_aead_authsize(aead)) {
-			pr_info("ESP: %s digestsize %u != %u\n",
-				x->aalg->alg_name,
-				crypto_aead_authsize(aead),
-				aalg_desc->uinfo.auth.icv_fullbits / 8);
+			NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 			goto free_key;
 		}
 
 		err = crypto_aead_setauthsize(
 			aead, x->aalg->alg_trunc_len / 8);
-		if (err)
+		if (err) {
+			NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 			goto free_key;
 		}
+	}
 
 	param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8);
 	memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8);
@@ -1132,7 +1138,7 @@ static int esp_init_authenc(struct xfrm_state *x)
 	return err;
 }
 
-static int esp_init_state(struct xfrm_state *x)
+static int esp_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	struct crypto_aead *aead;
 	u32 align;
@@ -1140,10 +1146,14 @@ static int esp_init_state(struct xfrm_state *x)
 
 	x->data = NULL;
 
-	if (x->aead)
-		err = esp_init_aead(x);
-	else
-		err = esp_init_authenc(x);
+	if (x->aead) {
+		err = esp_init_aead(x, extack);
+	} else if (x->ealg) {
+		err = esp_init_authenc(x, extack);
+	} else {
+		NL_SET_ERR_MSG(extack, "ESP: AEAD or CRYPT must be provided");
+		err = -EINVAL;
+	}
 
 	if (err)
 		goto error;
@@ -1161,6 +1171,7 @@ static int esp_init_state(struct xfrm_state *x)
 
 		switch (encap->encap_type) {
 		default:
+			NL_SET_ERR_MSG(extack, "Unsupported encapsulation type for ESP");
 			err = -EINVAL;
 			goto error;
 		case UDP_ENCAP_ESPINUDP:

net/ipv4/ipcomp.c

@@ -117,7 +117,8 @@ static int ipcomp_tunnel_attach(struct xfrm_state *x)
 	return err;
 }
 
-static int ipcomp4_init_state(struct xfrm_state *x)
+static int ipcomp4_init_state(struct xfrm_state *x,
+			      struct netlink_ext_ack *extack)
 {
 	int err = -EINVAL;
 
@@ -129,18 +130,21 @@ static int ipcomp4_init_state(struct xfrm_state *x)
 		x->props.header_len += sizeof(struct iphdr);
 		break;
 	default:
+		NL_SET_ERR_MSG(extack, "Unsupported XFRM mode for IPcomp");
 		goto out;
 	}
 
-	err = ipcomp_init_state(x);
+	err = ipcomp_init_state(x, extack);
 	if (err)
 		goto out;
 
 	if (x->props.mode == XFRM_MODE_TUNNEL) {
 		err = ipcomp_tunnel_attach(x);
-		if (err)
+		if (err) {
+			NL_SET_ERR_MSG(extack, "Kernel error: failed to initialize the associated state");
 			goto out;
 		}
+	}
 
 	err = 0;
 out:

net/ipv4/xfrm4_tunnel.c

@@ -22,13 +22,17 @@ static int ipip_xfrm_rcv(struct xfrm_state *x, struct sk_buff *skb)
 	return ip_hdr(skb)->protocol;
 }
 
-static int ipip_init_state(struct xfrm_state *x)
+static int ipip_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
-	if (x->props.mode != XFRM_MODE_TUNNEL)
+	if (x->props.mode != XFRM_MODE_TUNNEL) {
+		NL_SET_ERR_MSG(extack, "IPv4 tunnel can only be used with tunnel mode");
 		return -EINVAL;
+	}
 
-	if (x->encap)
+	if (x->encap) {
+		NL_SET_ERR_MSG(extack, "IPv4 tunnel is not compatible with encapsulation");
 		return -EINVAL;
+	}
 
 	x->props.header_len = sizeof(struct iphdr);
 

net/ipv6/ah6.c

@@ -666,30 +666,38 @@ static int ah6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 	return 0;
 }
 
-static int ah6_init_state(struct xfrm_state *x)
+static int ah6_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	struct ah_data *ahp = NULL;
 	struct xfrm_algo_desc *aalg_desc;
 	struct crypto_ahash *ahash;
 
-	if (!x->aalg)
+	if (!x->aalg) {
+		NL_SET_ERR_MSG(extack, "AH requires a state with an AUTH algorithm");
 		goto error;
+	}
 
-	if (x->encap)
+	if (x->encap) {
+		NL_SET_ERR_MSG(extack, "AH is not compatible with encapsulation");
 		goto error;
+	}
 
 	ahp = kzalloc(sizeof(*ahp), GFP_KERNEL);
 	if (!ahp)
 		return -ENOMEM;
 
 	ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0);
-	if (IS_ERR(ahash))
+	if (IS_ERR(ahash)) {
+		NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 		goto error;
+	}
 
 	ahp->ahash = ahash;
 	if (crypto_ahash_setkey(ahash, x->aalg->alg_key,
-			       (x->aalg->alg_key_len + 7) / 8))
+			       (x->aalg->alg_key_len + 7) / 8)) {
+		NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 		goto error;
+	}
 
 	/*
 	 * Lookup the algorithm description maintained by xfrm_algo,
@@ -702,9 +710,7 @@ static int ah6_init_state(struct xfrm_state *x)
 
 	if (aalg_desc->uinfo.auth.icv_fullbits/8 !=
 	    crypto_ahash_digestsize(ahash)) {
-		pr_info("AH: %s digestsize %u != %u\n",
-			x->aalg->alg_name, crypto_ahash_digestsize(ahash),
-			aalg_desc->uinfo.auth.icv_fullbits/8);
+		NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 		goto error;
 	}
 
@@ -721,6 +727,7 @@ static int ah6_init_state(struct xfrm_state *x)
 		x->props.header_len += sizeof(struct ipv6hdr);
 		break;
 	default:
+		NL_SET_ERR_MSG(extack, "Invalid mode requested for AH, must be one of TRANSPORT, TUNNEL, BEET");
 		goto error;
 	}
 	x->data = ahp;

net/ipv6/esp6.c

@@ -1051,16 +1051,17 @@ static void esp6_destroy(struct xfrm_state *x)
 	crypto_free_aead(aead);
 }
 
-static int esp_init_aead(struct xfrm_state *x)
+static int esp_init_aead(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	char aead_name[CRYPTO_MAX_ALG_NAME];
 	struct crypto_aead *aead;
 	int err;
 
-	err = -ENAMETOOLONG;
 	if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
-		     x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME)
-		goto error;
+		     x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME) {
+		NL_SET_ERR_MSG(extack, "Algorithm name is too long");
+		return -ENAMETOOLONG;
+	}
 
 	aead = crypto_alloc_aead(aead_name, 0, 0);
 	err = PTR_ERR(aead);
@@ -1078,11 +1079,15 @@ static int esp_init_aead(struct xfrm_state *x)
 	if (err)
 		goto error;
 
+	return 0;
+
 error:
+	NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 	return err;
 }
 
-static int esp_init_authenc(struct xfrm_state *x)
+static int esp_init_authenc(struct xfrm_state *x,
+			    struct netlink_ext_ack *extack)
 {
 	struct crypto_aead *aead;
 	struct crypto_authenc_key_param *param;
@@ -1093,10 +1098,6 @@ static int esp_init_authenc(struct xfrm_state *x)
 	unsigned int keylen;
 	int err;
 
-	err = -EINVAL;
-	if (!x->ealg)
-		goto error;
-
 	err = -ENAMETOOLONG;
 
 	if ((x->props.flags & XFRM_STATE_ESN)) {
@@ -1105,22 +1106,28 @@ static int esp_init_authenc(struct xfrm_state *x)
 			     x->geniv ?: "", x->geniv ? "(" : "",
 			     x->aalg ? x->aalg->alg_name : "digest_null",
 			     x->ealg->alg_name,
-			     x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME)
+			     x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) {
+			NL_SET_ERR_MSG(extack, "Algorithm name is too long");
 			goto error;
+		}
 	} else {
 		if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME,
 			     "%s%sauthenc(%s,%s)%s",
 			     x->geniv ?: "", x->geniv ? "(" : "",
 			     x->aalg ? x->aalg->alg_name : "digest_null",
 			     x->ealg->alg_name,
-			     x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME)
+			     x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) {
+			NL_SET_ERR_MSG(extack, "Algorithm name is too long");
 			goto error;
 		}
+	}
 
 	aead = crypto_alloc_aead(authenc_name, 0, 0);
 	err = PTR_ERR(aead);
-	if (IS_ERR(aead))
+	if (IS_ERR(aead)) {
+		NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 		goto error;
+	}
 
 	x->data = aead;
 
@@ -1150,18 +1157,17 @@ static int esp_init_authenc(struct xfrm_state *x)
 		err = -EINVAL;
 		if (aalg_desc->uinfo.auth.icv_fullbits / 8 !=
 		    crypto_aead_authsize(aead)) {
-			pr_info("ESP: %s digestsize %u != %u\n",
-				x->aalg->alg_name,
-				crypto_aead_authsize(aead),
-				aalg_desc->uinfo.auth.icv_fullbits / 8);
+			NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 			goto free_key;
 		}
 
 		err = crypto_aead_setauthsize(
 			aead, x->aalg->alg_trunc_len / 8);
-		if (err)
+		if (err) {
+			NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
 			goto free_key;
 		}
+	}
 
 	param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8);
 	memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8);
@@ -1175,7 +1181,7 @@ static int esp_init_authenc(struct xfrm_state *x)
 	return err;
 }
 
-static int esp6_init_state(struct xfrm_state *x)
+static int esp6_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	struct crypto_aead *aead;
 	u32 align;
@@ -1183,10 +1189,14 @@ static int esp6_init_state(struct xfrm_state *x)
 
 	x->data = NULL;
 
-	if (x->aead)
-		err = esp_init_aead(x);
-	else
-		err = esp_init_authenc(x);
+	if (x->aead) {
+		err = esp_init_aead(x, extack);
+	} else if (x->ealg) {
+		err = esp_init_authenc(x, extack);
+	} else {
+		NL_SET_ERR_MSG(extack, "ESP: AEAD or CRYPT must be provided");
+		err = -EINVAL;
+	}
 
 	if (err)
 		goto error;
@@ -1214,6 +1224,7 @@ static int esp6_init_state(struct xfrm_state *x)
 
 		switch (encap->encap_type) {
 		default:
+			NL_SET_ERR_MSG(extack, "Unsupported encapsulation type for ESP");
 			err = -EINVAL;
 			goto error;
 		case UDP_ENCAP_ESPINUDP:

net/ipv6/ipcomp6.c

@@ -136,7 +136,8 @@ static int ipcomp6_tunnel_attach(struct xfrm_state *x)
 	return err;
 }
 
-static int ipcomp6_init_state(struct xfrm_state *x)
+static int ipcomp6_init_state(struct xfrm_state *x,
+			      struct netlink_ext_ack *extack)
 {
 	int err = -EINVAL;
 
@@ -148,18 +149,21 @@ static int ipcomp6_init_state(struct xfrm_state *x)
 		x->props.header_len += sizeof(struct ipv6hdr);
 		break;
 	default:
+		NL_SET_ERR_MSG(extack, "Unsupported XFRM mode for IPcomp");
 		goto out;
 	}
 
-	err = ipcomp_init_state(x);
+	err = ipcomp_init_state(x, extack);
 	if (err)
 		goto out;
 
 	if (x->props.mode == XFRM_MODE_TUNNEL) {
 		err = ipcomp6_tunnel_attach(x);
-		if (err)
+		if (err) {
+			NL_SET_ERR_MSG(extack, "Kernel error: failed to initialize the associated state");
 			goto out;
 		}
+	}
 
 	err = 0;
 out:

net/ipv6/mip6.c

@@ -247,15 +247,14 @@ static int mip6_destopt_reject(struct xfrm_state *x, struct sk_buff *skb,
 	return err;
 }
 
-static int mip6_destopt_init_state(struct xfrm_state *x)
+static int mip6_destopt_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	if (x->id.spi) {
-		pr_info("%s: spi is not 0: %u\n", __func__, x->id.spi);
+		NL_SET_ERR_MSG(extack, "SPI must be 0");
 		return -EINVAL;
 	}
 	if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
-		pr_info("%s: state's mode is not %u: %u\n",
-			__func__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
+		NL_SET_ERR_MSG(extack, "XFRM mode must be XFRM_MODE_ROUTEOPTIMIZATION");
 		return -EINVAL;
 	}
 
@@ -333,15 +332,14 @@ static int mip6_rthdr_output(struct xfrm_state *x, struct sk_buff *skb)
 	return 0;
 }
 
-static int mip6_rthdr_init_state(struct xfrm_state *x)
+static int mip6_rthdr_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	if (x->id.spi) {
-		pr_info("%s: spi is not 0: %u\n", __func__, x->id.spi);
+		NL_SET_ERR_MSG(extack, "SPI must be 0");
 		return -EINVAL;
 	}
 	if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
-		pr_info("%s: state's mode is not %u: %u\n",
-			__func__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
+		NL_SET_ERR_MSG(extack, "XFRM mode must be XFRM_MODE_ROUTEOPTIMIZATION");
 		return -EINVAL;
 	}
 

net/ipv6/xfrm6_tunnel.c

@@ -270,13 +270,17 @@ static int xfrm6_tunnel_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 	return 0;
 }
 
-static int xfrm6_tunnel_init_state(struct xfrm_state *x)
+static int xfrm6_tunnel_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
-	if (x->props.mode != XFRM_MODE_TUNNEL)
+	if (x->props.mode != XFRM_MODE_TUNNEL) {
+		NL_SET_ERR_MSG(extack, "IPv6 tunnel can only be used with tunnel mode");
 		return -EINVAL;
+	}
 
-	if (x->encap)
+	if (x->encap) {
+		NL_SET_ERR_MSG(extack, "IPv6 tunnel is not compatible with encapsulation");
 		return -EINVAL;
+	}
 
 	x->props.header_len = sizeof(struct ipv6hdr);
 

net/xfrm/xfrm_device.c

@@ -207,7 +207,8 @@ struct sk_buff *validate_xmit_xfrm(struct sk_buff *skb, netdev_features_t featur
 EXPORT_SYMBOL_GPL(validate_xmit_xfrm);
 
 int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
-		       struct xfrm_user_offload *xuo)
+		       struct xfrm_user_offload *xuo,
+		       struct netlink_ext_ack *extack)
 {
 	int err;
 	struct dst_entry *dst;
@@ -216,15 +217,21 @@ int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
 	xfrm_address_t *saddr;
 	xfrm_address_t *daddr;
 
-	if (!x->type_offload)
+	if (!x->type_offload) {
+		NL_SET_ERR_MSG(extack, "Type doesn't support offload");
 		return -EINVAL;
+	}
 
 	/* We don't yet support UDP encapsulation and TFC padding. */
-	if (x->encap || x->tfcpad)
+	if (x->encap || x->tfcpad) {
+		NL_SET_ERR_MSG(extack, "Encapsulation and TFC padding can't be offloaded");
 		return -EINVAL;
+	}
 
-	if (xuo->flags & ~(XFRM_OFFLOAD_IPV6 | XFRM_OFFLOAD_INBOUND))
+	if (xuo->flags & ~(XFRM_OFFLOAD_IPV6 | XFRM_OFFLOAD_INBOUND)) {
+		NL_SET_ERR_MSG(extack, "Unrecognized flags in offload request");
 		return -EINVAL;
+	}
 
 	dev = dev_get_by_index(net, xuo->ifindex);
 	if (!dev) {
@@ -256,6 +263,7 @@ int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
 
 	if (x->props.flags & XFRM_STATE_ESN &&
 	    !dev->xfrmdev_ops->xdo_dev_state_advance_esn) {
+		NL_SET_ERR_MSG(extack, "Device doesn't support offload with ESN");
 		xso->dev = NULL;
 		dev_put(dev);
 		return -EINVAL;
@@ -277,9 +285,11 @@ int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
 		xso->real_dev = NULL;
 		netdev_put(dev, &xso->dev_tracker);
 
-		if (err != -EOPNOTSUPP)
+		if (err != -EOPNOTSUPP) {
+			NL_SET_ERR_MSG(extack, "Device failed to offload this state");
 			return err;
 		}
+	}
 
 	return 0;
 }

net/xfrm/xfrm_input.c

@@ -20,6 +20,7 @@
 #include <net/xfrm.h>
 #include <net/ip_tunnels.h>
 #include <net/ip6_tunnel.h>
+#include <net/dst_metadata.h>
 
 #include "xfrm_inout.h"
 
@@ -719,6 +720,7 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 		sp = skb_sec_path(skb);
 		if (sp)
 			sp->olen = 0;
+		if (skb_valid_dst(skb))
 			skb_dst_drop(skb);
 		gro_cells_receive(&gro_cells, skb);
 		return 0;
@@ -737,6 +739,7 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 			sp = skb_sec_path(skb);
 			if (sp)
 				sp->olen = 0;
+			if (skb_valid_dst(skb))
 				skb_dst_drop(skb);
 			gro_cells_receive(&gro_cells, skb);
 			return err;

net/xfrm/xfrm_interface.c

@@ -41,6 +41,7 @@
 #include <net/addrconf.h>
 #include <net/xfrm.h>
 #include <net/net_namespace.h>
+#include <net/dst_metadata.h>
 #include <net/netns/generic.h>
 #include <linux/etherdevice.h>
 
@@ -56,6 +57,89 @@ static const struct net_device_ops xfrmi_netdev_ops;
 struct xfrmi_net {
 	/* lists for storing interfaces in use */
 	struct xfrm_if __rcu *xfrmi[XFRMI_HASH_SIZE];
+	struct xfrm_if __rcu *collect_md_xfrmi;
+};
+
+static const struct nla_policy xfrm_lwt_policy[LWT_XFRM_MAX + 1] = {
+	[LWT_XFRM_IF_ID]	= NLA_POLICY_MIN(NLA_U32, 1),
+	[LWT_XFRM_LINK]		= NLA_POLICY_MIN(NLA_U32, 1),
+};
+
+static void xfrmi_destroy_state(struct lwtunnel_state *lwt)
+{
+}
+
+static int xfrmi_build_state(struct net *net, struct nlattr *nla,
+			     unsigned int family, const void *cfg,
+			     struct lwtunnel_state **ts,
+			     struct netlink_ext_ack *extack)
+{
+	struct nlattr *tb[LWT_XFRM_MAX + 1];
+	struct lwtunnel_state *new_state;
+	struct xfrm_md_info *info;
+	int ret;
+
+	ret = nla_parse_nested(tb, LWT_XFRM_MAX, nla, xfrm_lwt_policy, extack);
+	if (ret < 0)
+		return ret;
+
+	if (!tb[LWT_XFRM_IF_ID]) {
+		NL_SET_ERR_MSG(extack, "if_id must be set");
+		return -EINVAL;
+	}
+
+	new_state = lwtunnel_state_alloc(sizeof(*info));
+	if (!new_state) {
+		NL_SET_ERR_MSG(extack, "failed to create encap info");
+		return -ENOMEM;
+	}
+
+	new_state->type = LWTUNNEL_ENCAP_XFRM;
+
+	info = lwt_xfrm_info(new_state);
+
+	info->if_id = nla_get_u32(tb[LWT_XFRM_IF_ID]);
+
+	if (tb[LWT_XFRM_LINK])
+		info->link = nla_get_u32(tb[LWT_XFRM_LINK]);
+
+	*ts = new_state;
+	return 0;
+}
+
+static int xfrmi_fill_encap_info(struct sk_buff *skb,
+				 struct lwtunnel_state *lwt)
+{
+	struct xfrm_md_info *info = lwt_xfrm_info(lwt);
+
+	if (nla_put_u32(skb, LWT_XFRM_IF_ID, info->if_id) ||
+	    (info->link && nla_put_u32(skb, LWT_XFRM_LINK, info->link)))
+		return -EMSGSIZE;
+
+	return 0;
+}
+
+static int xfrmi_encap_nlsize(struct lwtunnel_state *lwtstate)
+{
+	return nla_total_size(sizeof(u32)) + /* LWT_XFRM_IF_ID */
+		nla_total_size(sizeof(u32)); /* LWT_XFRM_LINK */
+}
+
+static int xfrmi_encap_cmp(struct lwtunnel_state *a, struct lwtunnel_state *b)
+{
+	struct xfrm_md_info *a_info = lwt_xfrm_info(a);
+	struct xfrm_md_info *b_info = lwt_xfrm_info(b);
+
+	return memcmp(a_info, b_info, sizeof(*a_info));
+}
+
+static const struct lwtunnel_encap_ops xfrmi_encap_ops = {
+	.build_state	= xfrmi_build_state,
+	.destroy_state	= xfrmi_destroy_state,
+	.fill_encap	= xfrmi_fill_encap_info,
+	.get_encap_size = xfrmi_encap_nlsize,
+	.cmp_encap	= xfrmi_encap_cmp,
+	.owner		= THIS_MODULE,
 };
 
 #define for_each_xfrmi_rcu(start, xi) \
@@ -77,17 +161,23 @@ static struct xfrm_if *xfrmi_lookup(struct net *net, struct xfrm_state *x)
 			return xi;
 	}
 
+	xi = rcu_dereference(xfrmn->collect_md_xfrmi);
+	if (xi && (xi->dev->flags & IFF_UP))
+		return xi;
+
 	return NULL;
 }
 
-static struct xfrm_if *xfrmi_decode_session(struct sk_buff *skb,
-					    unsigned short family)
+static bool xfrmi_decode_session(struct sk_buff *skb,
+				 unsigned short family,
+				 struct xfrm_if_decode_session_result *res)
 {
 	struct net_device *dev;
+	struct xfrm_if *xi;
 	int ifindex = 0;
 
 	if (!secpath_exists(skb) || !skb->dev)
-		return NULL;
+		return false;
 
 	switch (family) {
 	case AF_INET6:
@@ -107,11 +197,18 @@ static struct xfrm_if *xfrmi_decode_session(struct sk_buff *skb,
 	}
 
 	if (!dev || !(dev->flags & IFF_UP))
-		return NULL;
+		return false;
 	if (dev->netdev_ops != &xfrmi_netdev_ops)
-		return NULL;
+		return false;
+
+	xi = netdev_priv(dev);
+	res->net = xi->net;
 
-	return netdev_priv(dev);
+	if (xi->p.collect_md)
+		res->if_id = xfrm_input_state(skb)->if_id;
+	else
+		res->if_id = xi->p.if_id;
+	return true;
 }
 
 static void xfrmi_link(struct xfrmi_net *xfrmn, struct xfrm_if *xi)
@@ -157,6 +254,9 @@ static int xfrmi_create(struct net_device *dev)
 	if (err < 0)
 		goto out;
 
+	if (xi->p.collect_md)
+		rcu_assign_pointer(xfrmn->collect_md_xfrmi, xi);
+	else
 		xfrmi_link(xfrmn, xi);
 
 	return 0;
@@ -185,6 +285,9 @@ static void xfrmi_dev_uninit(struct net_device *dev)
 	struct xfrm_if *xi = netdev_priv(dev);
 	struct xfrmi_net *xfrmn = net_generic(xi->net, xfrmi_net_id);
 
+	if (xi->p.collect_md)
+		RCU_INIT_POINTER(xfrmn->collect_md_xfrmi, NULL);
+	else
 		xfrmi_unlink(xfrmn, xi);
 }
 
@@ -214,6 +317,7 @@ static int xfrmi_rcv_cb(struct sk_buff *skb, int err)
 	struct xfrm_state *x;
 	struct xfrm_if *xi;
 	bool xnet;
+	int link;
 
 	if (err && !secpath_exists(skb))
 		return 0;
@@ -224,6 +328,7 @@ static int xfrmi_rcv_cb(struct sk_buff *skb, int err)
 	if (!xi)
 		return 1;
 
+	link = skb->dev->ifindex;
 	dev = xi->dev;
 	skb->dev = dev;
 
@@ -254,6 +359,17 @@ static int xfrmi_rcv_cb(struct sk_buff *skb, int err)
 	}
 
 	xfrmi_scrub_packet(skb, xnet);
+	if (xi->p.collect_md) {
+		struct metadata_dst *md_dst;
+
+		md_dst = metadata_dst_alloc(0, METADATA_XFRM, GFP_ATOMIC);
+		if (!md_dst)
+			return -ENOMEM;
+
+		md_dst->u.xfrm_info.if_id = x->if_id;
+		md_dst->u.xfrm_info.link = link;
+		skb_dst_set(skb, (struct dst_entry *)md_dst);
+	}
 	dev_sw_netstats_rx_add(dev, skb->len);
 
 	return 0;
@@ -269,10 +385,23 @@ xfrmi_xmit2(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
 	struct net_device *tdev;
 	struct xfrm_state *x;
 	int err = -1;
+	u32 if_id;
 	int mtu;
 
+	if (xi->p.collect_md) {
+		struct xfrm_md_info *md_info = skb_xfrm_md_info(skb);
+
+		if (unlikely(!md_info))
+			return -EINVAL;
+
+		if_id = md_info->if_id;
+		fl->flowi_oif = md_info->link;
+	} else {
+		if_id = xi->p.if_id;
+	}
+
 	dst_hold(dst);
-	dst = xfrm_lookup_with_ifid(xi->net, dst, fl, NULL, 0, xi->p.if_id);
+	dst = xfrm_lookup_with_ifid(xi->net, dst, fl, NULL, 0, if_id);
 	if (IS_ERR(dst)) {
 		err = PTR_ERR(dst);
 		dst = NULL;
@@ -283,7 +412,7 @@ xfrmi_xmit2(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
 	if (!x)
 		goto tx_err_link_failure;
 
-	if (x->if_id != xi->p.if_id)
+	if (x->if_id != if_id)
 		goto tx_err_link_failure;
 
 	tdev = dst->dev;
@@ -633,6 +762,9 @@ static void xfrmi_netlink_parms(struct nlattr *data[],
 
 	if (data[IFLA_XFRM_IF_ID])
 		parms->if_id = nla_get_u32(data[IFLA_XFRM_IF_ID]);
+
+	if (data[IFLA_XFRM_COLLECT_METADATA])
+		parms->collect_md = true;
 }
 
 static int xfrmi_newlink(struct net *src_net, struct net_device *dev,
@@ -645,6 +777,18 @@ static int xfrmi_newlink(struct net *src_net, struct net_device *dev,
 	int err;
 
 	xfrmi_netlink_parms(data, &p);
+	if (p.collect_md) {
+		struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
+
+		if (p.link || p.if_id) {
+			NL_SET_ERR_MSG(extack, "link and if_id must be zero");
+			return -EINVAL;
+		}
+
+		if (rtnl_dereference(xfrmn->collect_md_xfrmi))
+			return -EEXIST;
+
+	} else {
 		if (!p.if_id) {
 			NL_SET_ERR_MSG(extack, "if_id must be non zero");
 			return -EINVAL;
@@ -653,6 +797,7 @@ static int xfrmi_newlink(struct net *src_net, struct net_device *dev,
 		xi = xfrmi_locate(net, &p);
 		if (xi)
 			return -EEXIST;
+	}
 
 	xi = netdev_priv(dev);
 	xi->p = p;
@@ -682,12 +827,22 @@ static int xfrmi_changelink(struct net_device *dev, struct nlattr *tb[],
 		return -EINVAL;
 	}
 
+	if (p.collect_md) {
+		NL_SET_ERR_MSG(extack, "collect_md can't be changed");
+		return -EINVAL;
+	}
+
 	xi = xfrmi_locate(net, &p);
 	if (!xi) {
 		xi = netdev_priv(dev);
 	} else {
 		if (xi->dev != dev)
 			return -EEXIST;
+		if (xi->p.collect_md) {
+			NL_SET_ERR_MSG(extack,
+				       "device can't be changed to collect_md");
+			return -EINVAL;
+		}
 	}
 
 	return xfrmi_update(xi, &p);
@@ -700,6 +855,8 @@ static size_t xfrmi_get_size(const struct net_device *dev)
 		nla_total_size(4) +
 		/* IFLA_XFRM_IF_ID */
 		nla_total_size(4) +
+		/* IFLA_XFRM_COLLECT_METADATA */
+		nla_total_size(0) +
 		0;
 }
 
@@ -709,7 +866,8 @@ static int xfrmi_fill_info(struct sk_buff *skb, const struct net_device *dev)
 	struct xfrm_if_parms *parm = &xi->p;
 
 	if (nla_put_u32(skb, IFLA_XFRM_LINK, parm->link) ||
-	    nla_put_u32(skb, IFLA_XFRM_IF_ID, parm->if_id))
+	    nla_put_u32(skb, IFLA_XFRM_IF_ID, parm->if_id) ||
+	    (xi->p.collect_md && nla_put_flag(skb, IFLA_XFRM_COLLECT_METADATA)))
 		goto nla_put_failure;
 	return 0;
 
@@ -725,8 +883,10 @@ static struct net *xfrmi_get_link_net(const struct net_device *dev)
 }
 
 static const struct nla_policy xfrmi_policy[IFLA_XFRM_MAX + 1] = {
+	[IFLA_XFRM_UNSPEC]		= { .strict_start_type = IFLA_XFRM_COLLECT_METADATA },
 	[IFLA_XFRM_LINK]		= { .type = NLA_U32 },
 	[IFLA_XFRM_IF_ID]		= { .type = NLA_U32 },
+	[IFLA_XFRM_COLLECT_METADATA]	= { .type = NLA_FLAG },
 };
 
 static struct rtnl_link_ops xfrmi_link_ops __read_mostly = {
@@ -762,6 +922,9 @@ static void __net_exit xfrmi_exit_batch_net(struct list_head *net_exit_list)
 			     xip = &xi->next)
 				unregister_netdevice_queue(xi->dev, &list);
 		}
+		xi = rtnl_dereference(xfrmn->collect_md_xfrmi);
+		if (xi)
+			unregister_netdevice_queue(xi->dev, &list);
 	}
 	unregister_netdevice_many(&list);
 	rtnl_unlock();
@@ -999,6 +1162,8 @@ static int __init xfrmi_init(void)
 	if (err < 0)
 		goto rtnl_link_failed;
 
+	lwtunnel_encap_add_ops(&xfrmi_encap_ops, LWTUNNEL_ENCAP_XFRM);
+
 	xfrm_if_register_cb(&xfrm_if_cb);
 
 	return err;
@@ -1017,6 +1182,7 @@ static int __init xfrmi_init(void)
 static void __exit xfrmi_fini(void)
 {
 	xfrm_if_unregister_cb();
+	lwtunnel_encap_del_ops(&xfrmi_encap_ops, LWTUNNEL_ENCAP_XFRM);
 	rtnl_link_unregister(&xfrmi_link_ops);
 	xfrmi4_fini();
 	xfrmi6_fini();

net/xfrm/xfrm_ipcomp.c

@@ -325,18 +325,22 @@ void ipcomp_destroy(struct xfrm_state *x)
 }
 EXPORT_SYMBOL_GPL(ipcomp_destroy);
 
-int ipcomp_init_state(struct xfrm_state *x)
+int ipcomp_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	int err;
 	struct ipcomp_data *ipcd;
 	struct xfrm_algo_desc *calg_desc;
 
 	err = -EINVAL;
-	if (!x->calg)
+	if (!x->calg) {
+		NL_SET_ERR_MSG(extack, "Missing required compression algorithm");
 		goto out;
+	}
 
-	if (x->encap)
+	if (x->encap) {
+		NL_SET_ERR_MSG(extack, "IPComp is not compatible with encapsulation");
 		goto out;
+	}
 
 	err = -ENOMEM;
 	ipcd = kzalloc(sizeof(*ipcd), GFP_KERNEL);

net/xfrm/xfrm_policy.c

@@ -1889,7 +1889,7 @@ EXPORT_SYMBOL(xfrm_policy_walk_done);
  */
 static int xfrm_policy_match(const struct xfrm_policy *pol,
 			     const struct flowi *fl,
-			     u8 type, u16 family, int dir, u32 if_id)
+			     u8 type, u16 family, u32 if_id)
 {
 	const struct xfrm_selector *sel = &pol->selector;
 	int ret = -ESRCH;
@@ -2014,7 +2014,7 @@ static struct xfrm_policy *
 __xfrm_policy_eval_candidates(struct hlist_head *chain,
 			      struct xfrm_policy *prefer,
 			      const struct flowi *fl,
-			      u8 type, u16 family, int dir, u32 if_id)
+			      u8 type, u16 family, u32 if_id)
 {
 	u32 priority = prefer ? prefer->priority : ~0u;
 	struct xfrm_policy *pol;
@@ -2028,7 +2028,7 @@ __xfrm_policy_eval_candidates(struct hlist_head *chain,
 		if (pol->priority > priority)
 			break;
 
-		err = xfrm_policy_match(pol, fl, type, family, dir, if_id);
+		err = xfrm_policy_match(pol, fl, type, family, if_id);
 		if (err) {
 			if (err != -ESRCH)
 				return ERR_PTR(err);
@@ -2053,7 +2053,7 @@ static struct xfrm_policy *
 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand,
 			    struct xfrm_policy *prefer,
 			    const struct flowi *fl,
-			    u8 type, u16 family, int dir, u32 if_id)
+			    u8 type, u16 family, u32 if_id)
 {
 	struct xfrm_policy *tmp;
 	int i;
@@ -2061,8 +2061,7 @@ xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand,
 	for (i = 0; i < ARRAY_SIZE(cand->res); i++) {
 		tmp = __xfrm_policy_eval_candidates(cand->res[i],
 						    prefer,
-						    fl, type, family, dir,
-						    if_id);
+						    fl, type, family, if_id);
 		if (!tmp)
 			continue;
 
@@ -2101,7 +2100,7 @@ static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
 
 	ret = NULL;
 	hlist_for_each_entry_rcu(pol, chain, bydst) {
-		err = xfrm_policy_match(pol, fl, type, family, dir, if_id);
+		err = xfrm_policy_match(pol, fl, type, family, if_id);
 		if (err) {
 			if (err == -ESRCH)
 				continue;
@@ -2120,7 +2119,7 @@ static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
 		goto skip_inexact;
 
 	pol = xfrm_policy_eval_candidates(&cand, ret, fl, type,
-					  family, dir, if_id);
+					  family, if_id);
 	if (pol) {
 		ret = pol;
 		if (IS_ERR(pol))
@@ -3516,17 +3515,17 @@ int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
 	int xerr_idx = -1;
 	const struct xfrm_if_cb *ifcb;
 	struct sec_path *sp;
-	struct xfrm_if *xi;
 	u32 if_id = 0;
 
 	rcu_read_lock();
 	ifcb = xfrm_if_get_cb();
 
 	if (ifcb) {
-		xi = ifcb->decode_session(skb, family);
-		if (xi) {
-			if_id = xi->p.if_id;
-			net = xi->net;
+		struct xfrm_if_decode_session_result r;
+
+		if (ifcb->decode_session(skb, family, &r)) {
+			if_id = r.if_id;
+			net = r.net;
 		}
 	}
 	rcu_read_unlock();

net/xfrm/xfrm_replay.c

@@ -766,18 +766,22 @@ int xfrm_replay_overflow(struct xfrm_state *x, struct sk_buff *skb)
 }
 #endif
 
-int xfrm_init_replay(struct xfrm_state *x)
+int xfrm_init_replay(struct xfrm_state *x, struct netlink_ext_ack *extack)
 {
 	struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
 
 	if (replay_esn) {
 		if (replay_esn->replay_window >
-		    replay_esn->bmp_len * sizeof(__u32) * 8)
+		    replay_esn->bmp_len * sizeof(__u32) * 8) {
+			NL_SET_ERR_MSG(extack, "ESN replay window is too large for the chosen bitmap size");
 			return -EINVAL;
+		}
 
 		if (x->props.flags & XFRM_STATE_ESN) {
-			if (replay_esn->replay_window == 0)
+			if (replay_esn->replay_window == 0) {
+				NL_SET_ERR_MSG(extack, "ESN replay window must be > 0");
 				return -EINVAL;
+			}
 			x->repl_mode = XFRM_REPLAY_MODE_ESN;
 		} else {
 			x->repl_mode = XFRM_REPLAY_MODE_BMP;

net/xfrm/xfrm_state.c

@@ -2611,7 +2611,8 @@ u32 xfrm_state_mtu(struct xfrm_state *x, int mtu)
 }
 EXPORT_SYMBOL_GPL(xfrm_state_mtu);
 
-int __xfrm_init_state(struct xfrm_state *x, bool init_replay, bool offload)
+int __xfrm_init_state(struct xfrm_state *x, bool init_replay, bool offload,
+		      struct netlink_ext_ack *extack)
 {
 	const struct xfrm_mode *inner_mode;
 	const struct xfrm_mode *outer_mode;
@@ -2626,12 +2627,16 @@ int __xfrm_init_state(struct xfrm_state *x, bool init_replay, bool offload)
 
 	if (x->sel.family != AF_UNSPEC) {
 		inner_mode = xfrm_get_mode(x->props.mode, x->sel.family);
-		if (inner_mode == NULL)
+		if (inner_mode == NULL) {
+			NL_SET_ERR_MSG(extack, "Requested mode not found");
 			goto error;
+		}
 
 		if (!(inner_mode->flags & XFRM_MODE_FLAG_TUNNEL) &&
-		    family != x->sel.family)
+		    family != x->sel.family) {
+			NL_SET_ERR_MSG(extack, "Only tunnel modes can accommodate a change of family");
 			goto error;
+		}
 
 		x->inner_mode = *inner_mode;
 	} else {
@@ -2639,11 +2644,15 @@ int __xfrm_init_state(struct xfrm_state *x, bool init_replay, bool offload)
 		int iafamily = AF_INET;
 
 		inner_mode = xfrm_get_mode(x->props.mode, x->props.family);
-		if (inner_mode == NULL)
+		if (inner_mode == NULL) {
+			NL_SET_ERR_MSG(extack, "Requested mode not found");
 			goto error;
+		}
 
-		if (!(inner_mode->flags & XFRM_MODE_FLAG_TUNNEL))
+		if (!(inner_mode->flags & XFRM_MODE_FLAG_TUNNEL)) {
+			NL_SET_ERR_MSG(extack, "Only tunnel modes can accommodate an AF_UNSPEC selector");
 			goto error;
+		}
 
 		x->inner_mode = *inner_mode;
 
@@ -2658,24 +2667,27 @@ int __xfrm_init_state(struct xfrm_state *x, bool init_replay, bool offload)
 	}
 
 	x->type = xfrm_get_type(x->id.proto, family);
-	if (x->type == NULL)
+	if (x->type == NULL) {
+		NL_SET_ERR_MSG(extack, "Requested type not found");
 		goto error;
+	}
 
 	x->type_offload = xfrm_get_type_offload(x->id.proto, family, offload);
 
-	err = x->type->init_state(x);
+	err = x->type->init_state(x, extack);
 	if (err)
 		goto error;
 
 	outer_mode = xfrm_get_mode(x->props.mode, family);
 	if (!outer_mode) {
+		NL_SET_ERR_MSG(extack, "Requested mode not found");
 		err = -EPROTONOSUPPORT;
 		goto error;
 	}
 
 	x->outer_mode = *outer_mode;
 	if (init_replay) {
-		err = xfrm_init_replay(x);
+		err = xfrm_init_replay(x, extack);
 		if (err)
 			goto error;
 	}
@@ -2690,7 +2702,7 @@ int xfrm_init_state(struct xfrm_state *x)
 {
 	int err;
 
-	err = __xfrm_init_state(x, true, false);
+	err = __xfrm_init_state(x, true, false, NULL);
 	if (!err)
 		x->km.state = XFRM_STATE_VALID;
 

tools/testing/selftests/net/ipsec.c

@@ -58,6 +58,8 @@
 #define VETH_FMT	"ktst-%d"
 #define VETH_LEN	12
 
+#define XFRM_ALGO_NR_KEYS 29
+
 static int nsfd_parent	= -1;
 static int nsfd_childa	= -1;
 static int nsfd_childb	= -1;
@@ -75,6 +77,43 @@ const unsigned int ping_timeout		= 300;
 const unsigned int ping_count		= 100;
 const unsigned int ping_success		= 80;
 
+struct xfrm_key_entry {
+	char algo_name[35];
+	int key_len;
+};
+
+struct xfrm_key_entry xfrm_key_entries[] = {
+	{"digest_null", 0},
+	{"ecb(cipher_null)", 0},
+	{"cbc(des)", 64},
+	{"hmac(md5)", 128},
+	{"cmac(aes)", 128},
+	{"xcbc(aes)", 128},
+	{"cbc(cast5)", 128},
+	{"cbc(serpent)", 128},
+	{"hmac(sha1)", 160},
+	{"hmac(rmd160)", 160},
+	{"cbc(des3_ede)", 192},
+	{"hmac(sha256)", 256},
+	{"cbc(aes)", 256},
+	{"cbc(camellia)", 256},
+	{"cbc(twofish)", 256},
+	{"rfc3686(ctr(aes))", 288},
+	{"hmac(sha384)", 384},
+	{"cbc(blowfish)", 448},
+	{"hmac(sha512)", 512},
+	{"rfc4106(gcm(aes))-128", 160},
+	{"rfc4543(gcm(aes))-128", 160},
+	{"rfc4309(ccm(aes))-128", 152},
+	{"rfc4106(gcm(aes))-192", 224},
+	{"rfc4543(gcm(aes))-192", 224},
+	{"rfc4309(ccm(aes))-192", 216},
+	{"rfc4106(gcm(aes))-256", 288},
+	{"rfc4543(gcm(aes))-256", 288},
+	{"rfc4309(ccm(aes))-256", 280},
+	{"rfc7539(chacha20,poly1305)-128", 0}
+};
+
 static void randomize_buffer(void *buf, size_t buflen)
 {
 	int *p = (int *)buf;
@@ -767,65 +806,12 @@ static int do_ping(int cmd_fd, char *buf, size_t buf_len, struct in_addr from,
 static int xfrm_fill_key(char *name, char *buf,
 		size_t buf_len, unsigned int *key_len)
 {
-	/* TODO: use set/map instead */
-	if (strncmp(name, "digest_null", ALGO_LEN) == 0)
-		*key_len = 0;
-	else if (strncmp(name, "ecb(cipher_null)", ALGO_LEN) == 0)
-		*key_len = 0;
-	else if (strncmp(name, "cbc(des)", ALGO_LEN) == 0)
-		*key_len = 64;
-	else if (strncmp(name, "hmac(md5)", ALGO_LEN) == 0)
-		*key_len = 128;
-	else if (strncmp(name, "cmac(aes)", ALGO_LEN) == 0)
-		*key_len = 128;
-	else if (strncmp(name, "xcbc(aes)", ALGO_LEN) == 0)
-		*key_len = 128;
-	else if (strncmp(name, "cbc(cast5)", ALGO_LEN) == 0)
-		*key_len = 128;
-	else if (strncmp(name, "cbc(serpent)", ALGO_LEN) == 0)
-		*key_len = 128;
-	else if (strncmp(name, "hmac(sha1)", ALGO_LEN) == 0)
-		*key_len = 160;
-	else if (strncmp(name, "hmac(rmd160)", ALGO_LEN) == 0)
-		*key_len = 160;
-	else if (strncmp(name, "cbc(des3_ede)", ALGO_LEN) == 0)
-		*key_len = 192;
-	else if (strncmp(name, "hmac(sha256)", ALGO_LEN) == 0)
-		*key_len = 256;
-	else if (strncmp(name, "cbc(aes)", ALGO_LEN) == 0)
-		*key_len = 256;
-	else if (strncmp(name, "cbc(camellia)", ALGO_LEN) == 0)
-		*key_len = 256;
-	else if (strncmp(name, "cbc(twofish)", ALGO_LEN) == 0)
-		*key_len = 256;
-	else if (strncmp(name, "rfc3686(ctr(aes))", ALGO_LEN) == 0)
-		*key_len = 288;
-	else if (strncmp(name, "hmac(sha384)", ALGO_LEN) == 0)
-		*key_len = 384;
-	else if (strncmp(name, "cbc(blowfish)", ALGO_LEN) == 0)
-		*key_len = 448;
-	else if (strncmp(name, "hmac(sha512)", ALGO_LEN) == 0)
-		*key_len = 512;
-	else if (strncmp(name, "rfc4106(gcm(aes))-128", ALGO_LEN) == 0)
-		*key_len = 160;
-	else if (strncmp(name, "rfc4543(gcm(aes))-128", ALGO_LEN) == 0)
-		*key_len = 160;
-	else if (strncmp(name, "rfc4309(ccm(aes))-128", ALGO_LEN) == 0)
-		*key_len = 152;
-	else if (strncmp(name, "rfc4106(gcm(aes))-192", ALGO_LEN) == 0)
-		*key_len = 224;
-	else if (strncmp(name, "rfc4543(gcm(aes))-192", ALGO_LEN) == 0)
-		*key_len = 224;
-	else if (strncmp(name, "rfc4309(ccm(aes))-192", ALGO_LEN) == 0)
-		*key_len = 216;
-	else if (strncmp(name, "rfc4106(gcm(aes))-256", ALGO_LEN) == 0)
-		*key_len = 288;
-	else if (strncmp(name, "rfc4543(gcm(aes))-256", ALGO_LEN) == 0)
-		*key_len = 288;
-	else if (strncmp(name, "rfc4309(ccm(aes))-256", ALGO_LEN) == 0)
-		*key_len = 280;
-	else if (strncmp(name, "rfc7539(chacha20,poly1305)-128", ALGO_LEN) == 0)
-		*key_len = 0;
+	int i;
+
+	for (i = 0; i < XFRM_ALGO_NR_KEYS; i++) {
+		if (strncmp(name, xfrm_key_entries[i].algo_name, ALGO_LEN) == 0)
+			*key_len = xfrm_key_entries[i].key_len;
+	}
 
 	if (*key_len > buf_len) {
 		printk("Can't pack a key - too big for buffer");