// SPDX-License-Identifier: GPL-2.0 #include <linux/ip.h>#include <linux/skbuff.h>#include <net/ip6_checksum.h>#include <net/psp.h>#include <net/sock.h> #include "netdevsim.h" void nsim_psp_handle_ext(struct sk_buff *skb, struct skb_ext *psp_ext){	if (psp_ext)		__skb_ext_set(skb, SKB_EXT_PSP, psp_ext);} enum skb_drop_reasonnsim_do_psp(struct sk_buff *skb, struct netdevsim *ns,	    struct netdevsim *peer_ns, struct skb_ext **psp_ext){	enum skb_drop_reason rc = 0;	struct psp_dev *peer_psd;	struct psp_assoc *pas;	struct net *net;	int psp_len;	void **ptr; 	rcu_read_lock();	pas = psp_skb_get_assoc_rcu(skb);	if (!pas) {		rc = SKB_NOT_DROPPED_YET;		goto out_unlock;	} 	if (!skb_transport_header_was_set(skb)) {		rc = SKB_DROP_REASON_PSP_OUTPUT;		goto out_unlock;	} 	ptr = psp_assoc_drv_data(pas);	if (*ptr != ns) {		rc = SKB_DROP_REASON_PSP_OUTPUT;		goto out_unlock;	} 	net = sock_net(skb->sk);	if (!psp_dev_encapsulate(net, skb, pas->tx.spi, pas->version, 0)) {		rc = SKB_DROP_REASON_PSP_OUTPUT;		goto out_unlock;	} 	psp_len = skb->len - skb_inner_transport_offset(skb);	atomic64_inc(&ns->psp.tx_packets);	atomic64_add(psp_len, &ns->psp.tx_bytes); 	/* Now pretend we just received this frame */	peer_psd = rcu_dereference(peer_ns->psp.dev);	if (peer_psd && peer_psd->config.versions & (1 << pas->version)) {		bool strip_icv = false;		u8 generation; 		/* We cheat a bit and put the generation in the key.		 * In real life if generation was too old, then decryption would		 * fail. Here, we just make it so a bad key causes a bad		 * generation too, and psp_sk_rx_policy_check() will fail.		 */		generation = pas->tx.key[0]; 		skb_ext_reset(skb);		skb->mac_len = ETH_HLEN;		if (psp_dev_rcv(skb, peer_psd->id, generation, strip_icv)) {			rc = SKB_DROP_REASON_PSP_OUTPUT;			goto out_unlock;		} 		*psp_ext = skb->extensions;		refcount_inc(&(*psp_ext)->refcnt);		skb->decrypted = 1; 		atomic64_inc(&peer_ns->psp.rx_packets);		atomic64_add(psp_len, &peer_ns->psp.rx_bytes);	} else {		struct ipv6hdr *ip6h __maybe_unused;		struct iphdr *iph;		struct udphdr *uh;		__wsum csum;		int udplen; 		/* Do not decapsulate. Receive the skb with the udp and psp		 * headers still there as if this is a normal udp packet.		 * psp_dev_encapsulate() sets udp checksum to 0, so we need to		 * provide a valid checksum here, so the skb isn't dropped.		 */		uh = udp_hdr(skb);		udplen = udp_get_len(skb, uh, skb_transport_offset(skb));		csum = skb_checksum(skb, skb_transport_offset(skb),				    udplen, 0); 		switch (skb->protocol) {		case htons(ETH_P_IP):			iph = ip_hdr(skb);			uh->check = udp_v4_check(udplen, iph->saddr,						 iph->daddr, csum);			break;#if IS_ENABLED(CONFIG_IPV6)		case htons(ETH_P_IPV6):			ip6h = ipv6_hdr(skb);			uh->check = udp_v6_check(udplen, &ip6h->saddr,						 &ip6h->daddr, csum);			break;#endif		} 		uh->check	= uh->check ?: CSUM_MANGLED_0;		skb->ip_summed	= CHECKSUM_NONE;	} out_unlock:	rcu_read_unlock();	return rc;} static intnsim_psp_set_config(struct psp_dev *psd, struct psp_dev_config *conf,		    struct netlink_ext_ack *extack){	return 0;} static intnsim_rx_spi_alloc(struct psp_dev *psd, u32 version,		  struct psp_key_parsed *assoc,		  struct netlink_ext_ack *extack){	struct netdevsim *ns = psd->drv_priv;	int i; 	/* Check if incrementing the spi would change the phase bit */	if ((ns->psp.spi & PSP_SPI_KEY_ID) == PSP_SPI_KEY_ID) {		NL_SET_ERR_MSG(extack, "SPI space exhausted");		return -ENOSPC;	} 	assoc->spi = cpu_to_be32(++ns->psp.spi);	assoc->key[0] = psd->generation;	for (i = 1; i < PSP_MAX_KEY; i++)		assoc->key[i] = ns->psp.spi + i; 	return 0;} static int nsim_assoc_add(struct psp_dev *psd, struct psp_assoc *pas,			  struct netlink_ext_ack *extack){	struct netdevsim *ns = psd->drv_priv;	void **ptr = psp_assoc_drv_data(pas); 	/* Copy drv_priv from psd to assoc */	*ptr = psd->drv_priv;	ns->psp.assoc_cnt++; 	return 0;} static int nsim_key_rotate(struct psp_dev *psd, struct netlink_ext_ack *extack){	struct netdevsim *ns = psd->drv_priv; 	/* Flip key phase and reset SPI to 0 within that space	 * (will be pre-incremented, as 0 is an invalid SPI).	 */	if (ns->psp.spi & PSP_SPI_KEY_PHASE)		ns->psp.spi = 0;	else		ns->psp.spi = PSP_SPI_KEY_PHASE; 	return 0;} static void nsim_assoc_del(struct psp_dev *psd, struct psp_assoc *pas){	struct netdevsim *ns = psd->drv_priv;	void **ptr = psp_assoc_drv_data(pas); 	*ptr = NULL;	ns->psp.assoc_cnt--;} static void nsim_get_stats(struct psp_dev *psd, struct psp_dev_stats *stats){	struct netdevsim *ns = psd->drv_priv; 	/* WARNING: do *not* blindly zero stats in real drivers!	 * All required stats must be reported by the device!	 */	memset(stats, 0, sizeof(struct psp_dev_stats)); 	stats->rx_bytes = atomic64_read(&ns->psp.rx_bytes);	stats->rx_packets = atomic64_read(&ns->psp.rx_packets);	stats->tx_bytes = atomic64_read(&ns->psp.tx_bytes);	stats->tx_packets = atomic64_read(&ns->psp.tx_packets);} static struct psp_dev_ops nsim_psp_ops = {	.set_config	= nsim_psp_set_config,	.rx_spi_alloc	= nsim_rx_spi_alloc,	.tx_key_add	= nsim_assoc_add,	.tx_key_del	= nsim_assoc_del,	.key_rotate	= nsim_key_rotate,	.get_stats	= nsim_get_stats,}; static struct psp_dev_caps nsim_psp_caps = {	.versions = 1 << PSP_VERSION_HDR0_AES_GCM_128 |		    1 << PSP_VERSION_HDR0_AES_GMAC_128 |		    1 << PSP_VERSION_HDR0_AES_GCM_256 |		    1 << PSP_VERSION_HDR0_AES_GMAC_256,	.assoc_drv_spc = sizeof(void *),}; static void __nsim_psp_uninit(struct netdevsim *ns, bool teardown){	struct psp_dev *psd; 	psd = rcu_dereference_protected(ns->psp.dev,					teardown ||					lockdep_is_held(&ns->psp.rereg_lock));	if (psd) {		rcu_assign_pointer(ns->psp.dev, NULL);		synchronize_rcu();		psp_dev_unregister(psd);	}	WARN_ON(ns->psp.assoc_cnt);} void nsim_psp_uninit(struct netdevsim *ns){	debugfs_remove(ns->psp.rereg);	mutex_destroy(&ns->psp.rereg_lock);	__nsim_psp_uninit(ns, true);} static ssize_tnsim_psp_rereg_write(struct file *file, const char __user *data, size_t count,		     loff_t *ppos){	struct netdevsim *ns = file->private_data;	struct psp_dev *psd;	ssize_t ret; 	mutex_lock(&ns->psp.rereg_lock);	__nsim_psp_uninit(ns, false); 	psd = psp_dev_create(ns->netdev, &nsim_psp_ops, &nsim_psp_caps, ns);	if (IS_ERR(psd)) {		ret = PTR_ERR(psd);		goto out;	} 	rcu_assign_pointer(ns->psp.dev, psd);	ret = count;out:	mutex_unlock(&ns->psp.rereg_lock);	return ret;} static const struct file_operations nsim_psp_rereg_fops = {	.open = simple_open,	.write = nsim_psp_rereg_write,	.llseek = generic_file_llseek,	.owner = THIS_MODULE,}; int nsim_psp_init(struct netdevsim *ns){	struct dentry *ddir = ns->nsim_dev_port->ddir;	struct psp_dev *psd; 	psd = psp_dev_create(ns->netdev, &nsim_psp_ops, &nsim_psp_caps, ns);	if (IS_ERR(psd))		return PTR_ERR(psd); 	rcu_assign_pointer(ns->psp.dev, psd); 	mutex_init(&ns->psp.rereg_lock);	ns->psp.rereg = debugfs_create_file("psp_rereg", 0200, ddir, ns,					    &nsim_psp_rereg_fops);	return 0;}