[IPSEC] Add complete xfrm event notification

Heres the final patch.
What this patch provides

- netlink xfrm events
- ability to have events generated by netlink propagated to pfkey
  and vice versa.
- fixes the acquire lets-be-happy-with-one-success issue

Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 267 insertions, 5 deletions

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 97509011c274..bd8e6882c083 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -277,6 +277,7 @@ static int xfrm_add_sa(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfrma)
 	struct xfrm_usersa_info *p = NLMSG_DATA(nlh);
 	struct xfrm_state *x;
 	int err;
+	struct km_event c;
 
 	err = verify_newsa_info(p, (struct rtattr **) xfrma);
 	if (err)
@@ -286,6 +287,7 @@ static int xfrm_add_sa(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfrma)
 	if (!x)
 		return err;
 
+	xfrm_state_hold(x);
 	if (nlh->nlmsg_type == XFRM_MSG_NEWSA)
 		err = xfrm_state_add(x);
 	else
@@ -294,14 +296,27 @@ static int xfrm_add_sa(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfrma)
 	if (err < 0) {
 		x->km.state = XFRM_STATE_DEAD;
 		xfrm_state_put(x);
+		return err;
 	}
 
+	c.seq = nlh->nlmsg_seq;
+	c.pid = nlh->nlmsg_pid;
+	if (nlh->nlmsg_type == XFRM_MSG_NEWSA)
+		c.event = XFRM_SAP_ADDED;
+	else
+		c.event = XFRM_SAP_UPDATED;
+
+	km_state_notify(x, &c);
+	xfrm_state_put(x);
+
 	return err;
 }
 
 static int xfrm_del_sa(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfrma)
 {
 	struct xfrm_state *x;
+	int err;
+	struct km_event c;
 	struct xfrm_usersa_id *p = NLMSG_DATA(nlh);
 
 	x = xfrm_state_lookup(&p->daddr, p->spi, p->proto, p->family);
@@ -313,10 +328,19 @@ static int xfrm_del_sa(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfrma)
 		return -EPERM;
 	}
 
-	xfrm_state_delete(x);
+	err = xfrm_state_delete(x);
+	if (err < 0) {
+		xfrm_state_put(x);
+		return err;
+	}
+
+	c.seq = nlh->nlmsg_seq;
+	c.pid = nlh->nlmsg_pid;
+	c.event = XFRM_SAP_DELETED;
+	km_state_notify(x, &c);
 	xfrm_state_put(x);
 
-	return 0;
+	return err;
 }
 
 static void copy_to_user_state(struct xfrm_state *x, struct xfrm_usersa_info *p)
@@ -681,6 +705,7 @@ static int xfrm_add_policy(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfr
 {
 	struct xfrm_userpolicy_info *p = NLMSG_DATA(nlh);
 	struct xfrm_policy *xp;
+	struct km_event c;
 	int err;
 	int excl;
 
@@ -692,6 +717,10 @@ static int xfrm_add_policy(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfr
 	if (!xp)
 		return err;
 
+	/* shouldnt excl be based on nlh flags??
+	 * Aha! this is anti-netlink really i.e  more pfkey derived
+	 * in netlink excl is a flag and you wouldnt need
+	 * a type XFRM_MSG_UPDPOLICY - JHS */
 	excl = nlh->nlmsg_type == XFRM_MSG_NEWPOLICY;
 	err = xfrm_policy_insert(p->dir, xp, excl);
 	if (err) {
@@ -699,6 +728,15 @@ static int xfrm_add_policy(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfr
 		return err;
 	}
 
+	if (!excl)
+		c.event = XFRM_SAP_UPDATED;
+	else
+		c.event = XFRM_SAP_ADDED;
+
+	c.seq = nlh->nlmsg_seq;
+	c.pid = nlh->nlmsg_pid;
+	km_policy_notify(xp, p->dir, &c);
+
 	xfrm_pol_put(xp);
 
 	return 0;
@@ -816,6 +854,7 @@ static int xfrm_get_policy(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfr
 	struct xfrm_policy *xp;
 	struct xfrm_userpolicy_id *p;
 	int err;
+	struct km_event c;
 	int delete;
 
 	p = NLMSG_DATA(nlh);
@@ -843,6 +882,11 @@ static int xfrm_get_policy(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfr
 					      NETLINK_CB(skb).pid,
 					      MSG_DONTWAIT);
 		}
+	} else {
+		c.event = XFRM_SAP_DELETED;
+		c.seq = nlh->nlmsg_seq;
+		c.pid = nlh->nlmsg_pid;
+		km_policy_notify(xp, p->dir, &c);
 	}
 
 	xfrm_pol_put(xp);
@@ -852,15 +896,28 @@ static int xfrm_get_policy(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfr
 
 static int xfrm_flush_sa(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfrma)
 {
+	struct km_event c;
 	struct xfrm_usersa_flush *p = NLMSG_DATA(nlh);
 
 	xfrm_state_flush(p->proto);
+	c.data = p->proto;
+	c.event = XFRM_SAP_FLUSHED;
+	c.seq = nlh->nlmsg_seq;
+	c.pid = nlh->nlmsg_pid;
+	km_state_notify(NULL, &c);
+
 	return 0;
 }
 
 static int xfrm_flush_policy(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfrma)
 {
+	struct km_event c;
+
 	xfrm_policy_flush();
+	c.event = XFRM_SAP_FLUSHED;
+	c.seq = nlh->nlmsg_seq;
+	c.pid = nlh->nlmsg_pid;
+	km_policy_notify(NULL, 0, &c);
 	return 0;
 }
 
@@ -1069,10 +1126,12 @@ nlmsg_failure:
 	return -1;
 }
 
-static int xfrm_send_state_notify(struct xfrm_state *x, int hard)
+static int xfrm_exp_state_notify(struct xfrm_state *x, struct km_event *c)
 {
 	struct sk_buff *skb;
+	int hard = c ->data;
 
+	/* fix to do alloc using NLM macros */
 	skb = alloc_skb(sizeof(struct xfrm_user_expire) + 16, GFP_ATOMIC);
 	if (skb == NULL)
 		return -ENOMEM;
@@ -1085,6 +1144,122 @@ static int xfrm_send_state_notify(struct xfrm_state *x, int hard)
 	return netlink_broadcast(xfrm_nl, skb, 0, XFRMGRP_EXPIRE, GFP_ATOMIC);
 }
 
+static int xfrm_notify_sa_flush(struct km_event *c)
+{
+	struct xfrm_usersa_flush *p;
+	struct nlmsghdr *nlh;
+	struct sk_buff *skb;
+	unsigned char *b;
+	int len = NLMSG_LENGTH(sizeof(struct xfrm_usersa_flush));
+
+	skb = alloc_skb(len, GFP_ATOMIC);
+	if (skb == NULL)
+		return -ENOMEM;
+	b = skb->tail;
+
+	nlh = NLMSG_PUT(skb, c->pid, c->seq,
+			XFRM_MSG_FLUSHSA, sizeof(*p));
+	nlh->nlmsg_flags = 0;
+
+	p = NLMSG_DATA(nlh);
+	p->proto = c->data;
+
+	nlh->nlmsg_len = skb->tail - b;
+
+	return netlink_broadcast(xfrm_nl, skb, 0, XFRMGRP_SA, GFP_ATOMIC);
+
+nlmsg_failure:
+	kfree_skb(skb);
+	return -1;
+}
+
+static int inline xfrm_sa_len(struct xfrm_state *x)
+{
+	int l = NLMSG_LENGTH(sizeof(struct xfrm_usersa_info));
+	if (x->aalg)
+		l += RTA_SPACE(sizeof(*x->aalg) + (x->aalg->alg_key_len+7)/8);
+	if (x->ealg)
+		l += RTA_SPACE(sizeof(*x->ealg) + (x->ealg->alg_key_len+7)/8);
+	if (x->calg)
+		l += RTA_SPACE(sizeof(*x->calg));
+	if (x->encap)
+		l += RTA_SPACE(sizeof(*x->encap));
+
+	return l;
+}
+
+static int xfrm_notify_sa(struct xfrm_state *x, struct km_event *c)
+{
+	struct xfrm_usersa_info *p;
+	struct nlmsghdr *nlh;
+	struct sk_buff *skb;
+	u32 nlt;
+	unsigned char *b;
+	int len = xfrm_sa_len(x);
+
+	skb = alloc_skb(len, GFP_ATOMIC);
+	if (skb == NULL)
+		return -ENOMEM;
+	b = skb->tail;
+
+	if (c->event == XFRM_SAP_ADDED)
+		nlt = XFRM_MSG_NEWSA;
+	else if (c->event == XFRM_SAP_UPDATED)
+		nlt = XFRM_MSG_UPDSA;
+	else if (c->event == XFRM_SAP_DELETED)
+		nlt = XFRM_MSG_DELSA;
+	else
+		goto nlmsg_failure;
+
+	nlh = NLMSG_PUT(skb, c->pid, c->seq, nlt, sizeof(*p));
+	nlh->nlmsg_flags = 0;
+
+	p = NLMSG_DATA(nlh);
+	copy_to_user_state(x, p);
+
+	if (x->aalg)
+		RTA_PUT(skb, XFRMA_ALG_AUTH,
+			sizeof(*(x->aalg))+(x->aalg->alg_key_len+7)/8, x->aalg);
+	if (x->ealg)
+		RTA_PUT(skb, XFRMA_ALG_CRYPT,
+			sizeof(*(x->ealg))+(x->ealg->alg_key_len+7)/8, x->ealg);
+	if (x->calg)
+		RTA_PUT(skb, XFRMA_ALG_COMP, sizeof(*(x->calg)), x->calg);
+
+	if (x->encap)
+		RTA_PUT(skb, XFRMA_ENCAP, sizeof(*x->encap), x->encap);
+
+	nlh->nlmsg_len = skb->tail - b;
+
+	return netlink_broadcast(xfrm_nl, skb, 0, XFRMGRP_SA, GFP_ATOMIC);
+
+nlmsg_failure:
+rtattr_failure:
+	kfree_skb(skb);
+	return -1;
+}
+
+static int xfrm_send_state_notify(struct xfrm_state *x, struct km_event *c)
+{
+
+	switch (c->event) {
+	case XFRM_SAP_EXPIRED:
+		return xfrm_exp_state_notify(x, c);
+	case XFRM_SAP_DELETED:
+	case XFRM_SAP_UPDATED:
+	case XFRM_SAP_ADDED:
+		return xfrm_notify_sa(x, c);
+	case XFRM_SAP_FLUSHED:
+		return xfrm_notify_sa_flush(c);
+	default:
+		 printk("xfrm_user: Unknown SA event %d\n", c->event);
+		 break;
+	}
+
+	return 0;
+
+}
+
 static int build_acquire(struct sk_buff *skb, struct xfrm_state *x,
 			 struct xfrm_tmpl *xt, struct xfrm_policy *xp,
 			 int dir)
@@ -1218,7 +1393,7 @@ nlmsg_failure:
 	return -1;
 }
 
-static int xfrm_send_policy_notify(struct xfrm_policy *xp, int dir, int hard)
+static int xfrm_exp_policy_notify(struct xfrm_policy *xp, int dir, struct km_event *c)
 {
 	struct sk_buff *skb;
 	size_t len;
@@ -1229,7 +1404,7 @@ static int xfrm_send_policy_notify(struct xfrm_policy *xp, int dir, int hard)
 	if (skb == NULL)
 		return -ENOMEM;
 
-	if (build_polexpire(skb, xp, dir, hard) < 0)
+	if (build_polexpire(skb, xp, dir, c->data) < 0)
 		BUG();
 
 	NETLINK_CB(skb).dst_groups = XFRMGRP_EXPIRE;
@@ -1237,6 +1412,93 @@ static int xfrm_send_policy_notify(struct xfrm_policy *xp, int dir, int hard)
 	return netlink_broadcast(xfrm_nl, skb, 0, XFRMGRP_EXPIRE, GFP_ATOMIC);
 }
 
+static int xfrm_notify_policy(struct xfrm_policy *xp, int dir, struct km_event *c)
+{
+	struct xfrm_userpolicy_info *p;
+	struct nlmsghdr *nlh;
+	struct sk_buff *skb;
+	u32 nlt = 0 ;
+	unsigned char *b;
+	int len = RTA_SPACE(sizeof(struct xfrm_user_tmpl) * xp->xfrm_nr);
+	len += NLMSG_SPACE(sizeof(struct xfrm_userpolicy_info));
+
+	skb = alloc_skb(len, GFP_ATOMIC);
+	if (skb == NULL)
+		return -ENOMEM;
+	b = skb->tail;
+
+	if (c->event == XFRM_SAP_ADDED)
+		nlt = XFRM_MSG_NEWPOLICY;
+	else if (c->event == XFRM_SAP_UPDATED)
+		nlt = XFRM_MSG_UPDPOLICY;
+	else if (c->event == XFRM_SAP_DELETED)
+		nlt = XFRM_MSG_DELPOLICY;
+	else
+		goto nlmsg_failure;
+
+	nlh = NLMSG_PUT(skb, c->pid, c->seq, nlt, sizeof(*p));
+
+	p = NLMSG_DATA(nlh);
+
+	nlh->nlmsg_flags = 0;
+
+	copy_to_user_policy(xp, p, dir);
+	if (copy_to_user_tmpl(xp, skb) < 0)
+		goto nlmsg_failure;
+
+	nlh->nlmsg_len = skb->tail - b;
+
+	return netlink_broadcast(xfrm_nl, skb, 0, XFRMGRP_POLICY, GFP_ATOMIC);
+
+nlmsg_failure:
+	kfree_skb(skb);
+	return -1;
+}
+
+static int xfrm_notify_policy_flush(struct km_event *c)
+{
+	struct nlmsghdr *nlh;
+	struct sk_buff *skb;
+	unsigned char *b;
+	int len = NLMSG_LENGTH(0);
+
+	skb = alloc_skb(len, GFP_ATOMIC);
+	if (skb == NULL)
+		return -ENOMEM;
+	b = skb->tail;
+
+
+	nlh = NLMSG_PUT(skb, c->pid, c->seq, XFRM_MSG_FLUSHPOLICY, 0);
+
+	nlh->nlmsg_len = skb->tail - b;
+
+	return netlink_broadcast(xfrm_nl, skb, 0, XFRMGRP_POLICY, GFP_ATOMIC);
+
+nlmsg_failure:
+	kfree_skb(skb);
+	return -1;
+}
+
+static int xfrm_send_policy_notify(struct xfrm_policy *xp, int dir, struct km_event *c)
+{
+
+	switch (c->event) {
+	case XFRM_SAP_ADDED:
+	case XFRM_SAP_UPDATED:
+	case XFRM_SAP_DELETED:
+		return xfrm_notify_policy(xp, dir, c);
+	case XFRM_SAP_FLUSHED:
+		return xfrm_notify_policy_flush(c);
+	case XFRM_SAP_EXPIRED:
+		return xfrm_exp_policy_notify(xp, dir, c);
+	default:
+		printk("xfrm_user: Unknown Policy event %d\n", c->event);
+	}
+
+	return 0;
+
+}
+
 static struct xfrm_mgr netlink_mgr = {
 	.id		= "netlink",
 	.notify		= xfrm_send_state_notify,