v4.19.13 snapshot.
diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c
new file mode 100644
index 0000000..261995d
--- /dev/null
+++ b/net/xfrm/xfrm_output.c
@@ -0,0 +1,296 @@
+/*
+ * xfrm_output.c - Common IPsec encapsulation code.
+ *
+ * Copyright (c) 2007 Herbert Xu <herbert@gondor.apana.org.au>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/netfilter.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <net/dst.h>
+#include <net/xfrm.h>
+
+static int xfrm_output2(struct net *net, struct sock *sk, struct sk_buff *skb);
+
+static int xfrm_skb_check_space(struct sk_buff *skb)
+{
+ struct dst_entry *dst = skb_dst(skb);
+ int nhead = dst->header_len + LL_RESERVED_SPACE(dst->dev)
+ - skb_headroom(skb);
+ int ntail = dst->dev->needed_tailroom - skb_tailroom(skb);
+
+ if (nhead <= 0) {
+ if (ntail <= 0)
+ return 0;
+ nhead = 0;
+ } else if (ntail < 0)
+ ntail = 0;
+
+ return pskb_expand_head(skb, nhead, ntail, GFP_ATOMIC);
+}
+
+/* Children define the path of the packet through the
+ * Linux networking. Thus, destinations are stackable.
+ */
+
+static struct dst_entry *skb_dst_pop(struct sk_buff *skb)
+{
+ struct dst_entry *child = dst_clone(xfrm_dst_child(skb_dst(skb)));
+
+ skb_dst_drop(skb);
+ return child;
+}
+
+static int xfrm_output_one(struct sk_buff *skb, int err)
+{
+ struct dst_entry *dst = skb_dst(skb);
+ struct xfrm_state *x = dst->xfrm;
+ struct net *net = xs_net(x);
+
+ if (err <= 0)
+ goto resume;
+
+ do {
+ err = xfrm_skb_check_space(skb);
+ if (err) {
+ XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTERROR);
+ goto error_nolock;
+ }
+
+ skb->mark = xfrm_smark_get(skb->mark, x);
+
+ err = x->outer_mode->output(x, skb);
+ if (err) {
+ XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTSTATEMODEERROR);
+ goto error_nolock;
+ }
+
+ spin_lock_bh(&x->lock);
+
+ if (unlikely(x->km.state != XFRM_STATE_VALID)) {
+ XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTSTATEINVALID);
+ err = -EINVAL;
+ goto error;
+ }
+
+ err = xfrm_state_check_expire(x);
+ if (err) {
+ XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTSTATEEXPIRED);
+ goto error;
+ }
+
+ err = x->repl->overflow(x, skb);
+ if (err) {
+ XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTSTATESEQERROR);
+ goto error;
+ }
+
+ x->curlft.bytes += skb->len;
+ x->curlft.packets++;
+
+ spin_unlock_bh(&x->lock);
+
+ skb_dst_force(skb);
+ if (!skb_dst(skb)) {
+ XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTERROR);
+ goto error_nolock;
+ }
+
+ if (xfrm_offload(skb)) {
+ x->type_offload->encap(x, skb);
+ } else {
+ /* Inner headers are invalid now. */
+ skb->encapsulation = 0;
+
+ err = x->type->output(x, skb);
+ if (err == -EINPROGRESS)
+ goto out;
+ }
+
+resume:
+ if (err) {
+ XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTSTATEPROTOERROR);
+ goto error_nolock;
+ }
+
+ dst = skb_dst_pop(skb);
+ if (!dst) {
+ XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTERROR);
+ err = -EHOSTUNREACH;
+ goto error_nolock;
+ }
+ skb_dst_set(skb, dst);
+ x = dst->xfrm;
+ } while (x && !(x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL));
+
+ return 0;
+
+error:
+ spin_unlock_bh(&x->lock);
+error_nolock:
+ kfree_skb(skb);
+out:
+ return err;
+}
+
+int xfrm_output_resume(struct sk_buff *skb, int err)
+{
+ struct net *net = xs_net(skb_dst(skb)->xfrm);
+
+ while (likely((err = xfrm_output_one(skb, err)) == 0)) {
+ nf_reset(skb);
+
+ err = skb_dst(skb)->ops->local_out(net, skb->sk, skb);
+ if (unlikely(err != 1))
+ goto out;
+
+ if (!skb_dst(skb)->xfrm)
+ return dst_output(net, skb->sk, skb);
+
+ err = nf_hook(skb_dst(skb)->ops->family,
+ NF_INET_POST_ROUTING, net, skb->sk, skb,
+ NULL, skb_dst(skb)->dev, xfrm_output2);
+ if (unlikely(err != 1))
+ goto out;
+ }
+
+ if (err == -EINPROGRESS)
+ err = 0;
+
+out:
+ return err;
+}
+EXPORT_SYMBOL_GPL(xfrm_output_resume);
+
+static int xfrm_output2(struct net *net, struct sock *sk, struct sk_buff *skb)
+{
+ return xfrm_output_resume(skb, 1);
+}
+
+static int xfrm_output_gso(struct net *net, struct sock *sk, struct sk_buff *skb)
+{
+ struct sk_buff *segs;
+
+ BUILD_BUG_ON(sizeof(*IPCB(skb)) > SKB_SGO_CB_OFFSET);
+ BUILD_BUG_ON(sizeof(*IP6CB(skb)) > SKB_SGO_CB_OFFSET);
+ segs = skb_gso_segment(skb, 0);
+ kfree_skb(skb);
+ if (IS_ERR(segs))
+ return PTR_ERR(segs);
+ if (segs == NULL)
+ return -EINVAL;
+
+ do {
+ struct sk_buff *nskb = segs->next;
+ int err;
+
+ segs->next = NULL;
+ err = xfrm_output2(net, sk, segs);
+
+ if (unlikely(err)) {
+ kfree_skb_list(nskb);
+ return err;
+ }
+
+ segs = nskb;
+ } while (segs);
+
+ return 0;
+}
+
+int xfrm_output(struct sock *sk, struct sk_buff *skb)
+{
+ struct net *net = dev_net(skb_dst(skb)->dev);
+ struct xfrm_state *x = skb_dst(skb)->xfrm;
+ int err;
+
+ secpath_reset(skb);
+
+ if (xfrm_dev_offload_ok(skb, x)) {
+ struct sec_path *sp;
+
+ sp = secpath_dup(skb->sp);
+ if (!sp) {
+ XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTERROR);
+ kfree_skb(skb);
+ return -ENOMEM;
+ }
+ if (skb->sp)
+ secpath_put(skb->sp);
+ skb->sp = sp;
+ skb->encapsulation = 1;
+
+ sp->olen++;
+ sp->xvec[skb->sp->len++] = x;
+ xfrm_state_hold(x);
+
+ if (skb_is_gso(skb)) {
+ skb_shinfo(skb)->gso_type |= SKB_GSO_ESP;
+
+ return xfrm_output2(net, sk, skb);
+ }
+
+ if (x->xso.dev && x->xso.dev->features & NETIF_F_HW_ESP_TX_CSUM)
+ goto out;
+ }
+
+ if (skb_is_gso(skb))
+ return xfrm_output_gso(net, sk, skb);
+
+ if (skb->ip_summed == CHECKSUM_PARTIAL) {
+ err = skb_checksum_help(skb);
+ if (err) {
+ XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTERROR);
+ kfree_skb(skb);
+ return err;
+ }
+ }
+
+out:
+ return xfrm_output2(net, sk, skb);
+}
+EXPORT_SYMBOL_GPL(xfrm_output);
+
+int xfrm_inner_extract_output(struct xfrm_state *x, struct sk_buff *skb)
+{
+ struct xfrm_mode *inner_mode;
+ if (x->sel.family == AF_UNSPEC)
+ inner_mode = xfrm_ip2inner_mode(x,
+ xfrm_af2proto(skb_dst(skb)->ops->family));
+ else
+ inner_mode = x->inner_mode;
+
+ if (inner_mode == NULL)
+ return -EAFNOSUPPORT;
+ return inner_mode->afinfo->extract_output(x, skb);
+}
+EXPORT_SYMBOL_GPL(xfrm_inner_extract_output);
+
+void xfrm_local_error(struct sk_buff *skb, int mtu)
+{
+ unsigned int proto;
+ struct xfrm_state_afinfo *afinfo;
+
+ if (skb->protocol == htons(ETH_P_IP))
+ proto = AF_INET;
+ else if (skb->protocol == htons(ETH_P_IPV6))
+ proto = AF_INET6;
+ else
+ return;
+
+ afinfo = xfrm_state_get_afinfo(proto);
+ if (afinfo) {
+ afinfo->local_error(skb, mtu);
+ rcu_read_unlock();
+ }
+}
+EXPORT_SYMBOL_GPL(xfrm_local_error);