[crypto 3/8] chtls: ulp for Inline TLS processing

[Atul Gupta <atul.gupta@chelsio.com>]

Register chtls as another tcp ULP, Based on a similar infrastructure
in tcp_cong. proto_ops are defined to handle CPL to send/receive
crypto request to hw.

Signed-off-by: Atul Gupta <atul.gupta@chelsio.com>
---
 drivers/crypto/chelsio/chtls/chtls_main.c | 585 ++++++++++++++++++++++++++++++
 1 file changed, 585 insertions(+)
 create mode 100644 drivers/crypto/chelsio/chtls/chtls_main.c

diff --git a/drivers/crypto/chelsio/chtls/chtls_main.c b/drivers/crypto/chelsio/chtls/chtls_main.c
new file mode 100644
index 0000000..e951b4e
--- /dev/null
+++ b/drivers/crypto/chelsio/chtls/chtls_main.c
@@ -0,0 +1,585 @@
+/*
+ * Copyright (c) 2017 Chelsio Communications, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Written by: Atul Gupta (atul.gupta@chelsio.com)
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/socket.h>
+#include <linux/hash.h>
+#include <linux/in.h>
+#include <linux/net.h>
+#include <linux/ip.h>
+#include <linux/tcp.h>
+#include <net/tcp.h>
+#include <net/tls.h>
+
+#include "chtls.h"
+#include "chtls_cm.h"
+
+#define DRV_NAME "chtls"
+
+/*
+ * chtls device management
+ * maintains a list of the chtls devices
+ */
+static LIST_HEAD(cdev_list);
+static DEFINE_MUTEX(cdev_mutex);
+static DEFINE_MUTEX(cdev_list_lock);
+
+static struct proto chtls_base_prot;
+static struct proto chtls_cpl_prot;
+static DEFINE_MUTEX(notify_mutex);
+static RAW_NOTIFIER_HEAD(listen_notify_list);
+struct request_sock_ops chtls_rsk_ops;
+static uint send_page_order = (14 - PAGE_SHIFT < 0) ? 0 : 14 - PAGE_SHIFT;
+
+int register_listen_notifier(struct notifier_block *nb)
+{
+	int err;
+
+	mutex_lock(&notify_mutex);
+	err = raw_notifier_chain_register(&listen_notify_list, nb);
+	mutex_unlock(&notify_mutex);
+	return err;
+}
+
+int unregister_listen_notifier(struct notifier_block *nb)
+{
+	int err;
+
+	mutex_lock(&notify_mutex);
+	err = raw_notifier_chain_unregister(&listen_notify_list, nb);
+	mutex_unlock(&notify_mutex);
+	return err;
+}
+
+int listen_notify_handler(struct notifier_block *this,
+			  unsigned long event, void *data)
+{
+	struct sock *sk = data;
+	struct chtls_dev *cdev;
+	int ret =  NOTIFY_DONE;
+
+	switch (event) {
+	case CHTLS_LISTEN_START:
+	case CHTLS_LISTEN_STOP:
+		mutex_lock(&cdev_list_lock);
+		list_for_each_entry(cdev, &cdev_list, list) {
+			if (event == CHTLS_LISTEN_START)
+				ret = chtls_listen_start(cdev, sk);
+			else
+				chtls_listen_stop(cdev, sk);
+		}
+		mutex_unlock(&cdev_list_lock);
+		break;
+	}
+	return ret;
+}
+
+static struct notifier_block listen_notifier = {
+	.notifier_call = listen_notify_handler
+};
+
+static int listen_backlog_rcv(struct sock *sk, struct sk_buff *skb)
+{
+	if (likely(skb_transport_header(skb) != skb_network_header(skb)))
+		return tcp_v4_do_rcv(sk, skb);
+	BLOG_SKB_CB(skb)->backlog_rcv(sk, skb);
+	return 0;
+}
+
+static int chtls_start_listen(struct sock *sk)
+{
+	int err;
+
+	if (sk->sk_protocol != IPPROTO_TCP)
+		return -EPROTONOSUPPORT;
+
+	if (sk->sk_family == PF_INET &&
+	    LOOPBACK(inet_sk(sk)->inet_rcv_saddr))
+		return -EADDRNOTAVAIL;
+
+	sk->sk_backlog_rcv = listen_backlog_rcv;
+	mutex_lock(&notify_mutex);
+	err = raw_notifier_call_chain(&listen_notify_list, 0, sk);
+	mutex_unlock(&notify_mutex);
+	return err;
+}
+
+static int chtls_hash(struct sock *sk)
+{
+	int err;
+
+	err = tcp_prot.hash(sk);
+	if (sk->sk_state == TCP_LISTEN)
+		err |= chtls_start_listen(sk);
+
+	if (err)
+		tcp_prot.unhash(sk);
+	return err;
+}
+
+int chtls_stop_listen(struct sock *sk)
+{
+	if (sk->sk_protocol != IPPROTO_TCP)
+		return -EPROTONOSUPPORT;
+
+	mutex_lock(&notify_mutex);
+	raw_notifier_call_chain(&listen_notify_list, 1, sk);
+	mutex_unlock(&notify_mutex);
+	return 0;
+}
+
+static void chtls_unhash(struct sock *sk)
+{
+	if (sk->sk_state == TCP_LISTEN)
+		chtls_stop_listen(sk);
+	tcp_prot.unhash(sk);
+}
+
+static void chtls_lsk_close(struct sock *sk, long timeout)
+{
+	struct tls_context *ctx = tls_get_ctx(sk);
+	void (*sk_proto_close)(struct sock *sk, long timeout);
+
+	lock_sock(sk);
+	sk_proto_close = ctx->sk_proto_close;
+	kfree(ctx);
+
+	release_sock(sk);
+	sk_proto_close(sk, timeout);
+}
+
+static void process_deferq(struct work_struct *task_param)
+{
+	struct sk_buff *skb;
+	struct chtls_dev *cdev = container_of(task_param,
+				struct chtls_dev, deferq_task);
+
+	spin_lock_bh(&cdev->deferq.lock);
+	while ((skb = __skb_dequeue(&cdev->deferq)) != NULL) {
+		spin_unlock_bh(&cdev->deferq.lock);
+		DEFERRED_SKB_CB(skb)->handler(cdev, skb);
+		spin_lock_bh(&cdev->deferq.lock);
+	}
+	spin_unlock_bh(&cdev->deferq.lock);
+}
+
+static int chtls_get_skb(struct chtls_dev *cdev)
+{
+	cdev->askb = alloc_skb(sizeof(struct tcphdr), GFP_KERNEL);
+	if (!cdev->askb)
+		return 1;
+
+	skb_put(cdev->askb, sizeof(struct tcphdr));
+	skb_reset_transport_header(cdev->askb);
+	memset(cdev->askb->data, 0, cdev->askb->len);
+	return 0;
+}
+
+static void *chtls_uld_add(const struct cxgb4_lld_info *info)
+{
+	struct chtls_dev *cdev;
+	struct cxgb4_lld_info *lldi;
+	int i;
+
+	cdev = kzalloc(sizeof(*cdev) + info->nports *
+		      (sizeof(struct net_device *)), GFP_KERNEL);
+	if (!cdev)
+		return NULL;
+
+	lldi = kzalloc(sizeof(*lldi), GFP_KERNEL);
+	if (!lldi) {
+		kfree(cdev);
+		return NULL;
+	}
+
+	if (chtls_get_skb(cdev)) {
+		kfree(lldi);
+		kfree(cdev);
+		return NULL;
+	}
+	*lldi = *info;
+	cdev->lldi = lldi;
+	cdev->pdev = lldi->pdev;
+	cdev->tids = lldi->tids;
+	cdev->ports = (struct net_device **)(cdev + 1);
+	cdev->ports = lldi->ports;
+	cdev->mtus = lldi->mtus;
+	cdev->tids = lldi->tids;
+	cdev->pfvf = FW_VIID_PFN_G(cxgb4_port_viid(lldi->ports[0]))
+			<< FW_VIID_PFN_S;
+
+	for (i = 0; i < (1 << RSPQ_HASH_BITS); i++) {
+		unsigned int size = 64 - sizeof(struct rsp_ctrl) - 8;
+
+		cdev->rspq_skb_cache[i] = __alloc_skb(size,
+						      gfp_any(), 0,
+						      lldi->nodeid);
+	}
+
+	idr_init(&cdev->aidr);
+	idr_init(&cdev->hwtid_idr);
+	INIT_WORK(&cdev->deferq_task, process_deferq);
+	spin_lock_init(&cdev->listen_lock);
+	spin_lock_init(&cdev->idr_lock);
+	spin_lock_init(&cdev->aidr_lock);
+	cdev->send_page_order = min_t(uint, get_order(32768),
+				      send_page_order);
+
+	if (lldi->vr->key.size)
+		chtls_init_kmap(cdev, lldi);
+
+	mutex_lock(&cdev_mutex);
+	list_add_tail(&cdev->list, &cdev_list);
+	mutex_unlock(&cdev_mutex);
+
+	return cdev;
+}
+
+static void chtls_free_uld(struct chtls_dev *cdev)
+{
+	int i;
+
+	mutex_lock(&cdev_mutex);
+	list_del(&cdev->list);
+	mutex_unlock(&cdev_mutex);
+	chtls_free_kmap(cdev);
+	idr_destroy(&cdev->hwtid_idr);
+	idr_destroy(&cdev->aidr);
+	for (i = 0; i < (1 << RSPQ_HASH_BITS); i++) {
+		kfree_skb(cdev->rspq_skb_cache[i]);
+		cdev->rspq_skb_cache[i] = NULL;
+	}
+	kfree(cdev->lldi);
+	if (cdev->askb)
+		kfree_skb(cdev->askb);
+	kfree(cdev);
+}
+
+static void chtls_free_all_uld(void)
+{
+	struct chtls_dev *cdev, *tmp;
+
+	list_for_each_entry_safe(cdev, tmp, &cdev_list, list)
+		chtls_free_uld(cdev);
+}
+
+static int chtls_uld_state_change(void *handle, enum cxgb4_state new_state)
+{
+	struct chtls_dev *cdev = handle;
+
+	switch (new_state) {
+	case CXGB4_STATE_UP:
+		break;
+	case CXGB4_STATE_DOWN:
+		break;
+	case CXGB4_STATE_START_RECOVERY:
+		break;
+	case CXGB4_STATE_DETACH:
+		chtls_free_uld(cdev);
+		break;
+	}
+	return 0;
+}
+
+struct sk_buff *copy_gl_to_skb_pkt(const struct pkt_gl *gl,
+				   const __be64 *rsp,
+				   u32 pktshift)
+{
+	struct sk_buff *skb;
+
+	/* Allocate space for cpl_pass_accpet_req which will be synthesized by
+	 * driver. Once driver synthesizes cpl_pass_accpet_req the skb will go
+	 * through the regular cpl_pass_accept_req processing in TOM.
+	 */
+	skb = alloc_skb(gl->tot_len + sizeof(struct cpl_pass_accept_req)
+			- pktshift, GFP_ATOMIC);
+	if (unlikely(!skb))
+		return NULL;
+	__skb_put(skb, gl->tot_len + sizeof(struct cpl_pass_accept_req)
+		   - pktshift);
+	/* For now we will copy  cpl_rx_pkt in the skb */
+	skb_copy_to_linear_data(skb, rsp, sizeof(struct cpl_rx_pkt));
+	skb_copy_to_linear_data_offset(skb, sizeof(struct cpl_pass_accept_req)
+				       , gl->va + pktshift,
+				       gl->tot_len - pktshift);
+
+	return skb;
+}
+
+int chtls_recv_packet(struct chtls_dev *cdev,
+		      const struct pkt_gl *gl, const __be64 *rsp)
+{
+	unsigned int opcode = *(u8 *)rsp;
+	struct sk_buff *skb;
+	int ret;
+
+	skb = copy_gl_to_skb_pkt(gl, rsp, cdev->lldi->sge_pktshift);
+	if (!skb)
+		return -ENOMEM;
+
+	ret = chtls_handlers[opcode](cdev, skb);
+	if (ret & CPL_RET_BUF_DONE)
+		kfree_skb(skb);
+
+	return 0;
+}
+
+static int chtls_recv_rsp(struct chtls_dev *cdev, const __be64 *rsp)
+{
+	unsigned int opcode = *(u8 *)rsp;
+	unsigned int len = 64 - sizeof(struct rsp_ctrl) - 8;
+	struct sk_buff *skb;
+	unsigned long rspq_bin;
+	int ret;
+
+	rspq_bin = hash_ptr((void *)rsp, RSPQ_HASH_BITS);
+	skb = cdev->rspq_skb_cache[rspq_bin];
+	if (skb && !skb_is_nonlinear(skb) &&
+	    !skb_shared(skb) && !skb_cloned(skb)) {
+		refcount_inc(&skb->users);
+		if (refcount_read(&skb->users) == 2) {
+			__skb_trim(skb, 0);
+			if (skb_tailroom(skb) >= len)
+				goto copy_out;
+		}
+		refcount_dec(&skb->users);
+	}
+	skb = alloc_skb(len, GFP_ATOMIC);
+	if (unlikely(!skb))
+		return 1;
+
+copy_out:
+	__skb_put(skb, len);
+	skb_copy_to_linear_data(skb, rsp, len);
+	skb_reset_network_header(skb);
+	skb_reset_transport_header(skb);
+	ret = chtls_handlers[opcode](cdev, skb);
+
+	if (ret & CPL_RET_BUF_DONE)
+		kfree_skb(skb);
+	return 0;
+}
+
+static int chtls_recv(struct chtls_dev *cdev,
+		      struct sk_buff **skbs, const __be64 *rsp)
+{
+	struct sk_buff *skb = *skbs;
+	unsigned int opcode = *(u8 *)rsp;
+	int ret;
+
+	__skb_push(skb, sizeof(struct rss_header));
+	skb_copy_to_linear_data(skb, rsp, sizeof(struct rss_header));
+
+	ret = chtls_handlers[opcode](cdev, skb);
+	if (ret & CPL_RET_BUF_DONE)
+		kfree_skb(skb);
+
+	return 0;
+}
+
+static int chtls_uld_rx_handler(void *handle, const __be64 *rsp,
+				const struct pkt_gl *gl)
+{
+	struct chtls_dev *cdev = handle;
+	struct sk_buff *skb;
+	unsigned int opcode = *(u8 *)rsp;
+
+	if (unlikely(opcode == CPL_RX_PKT)) {
+		if (chtls_recv_packet(cdev, gl, rsp) < 0)
+			goto nomem;
+		return 0;
+	}
+
+	if (!gl)
+		return chtls_recv_rsp(cdev, rsp);
+
+#define RX_PULL_LEN 128
+	skb = cxgb4_pktgl_to_skb(gl, RX_PULL_LEN, RX_PULL_LEN);
+	if (unlikely(!skb))
+		goto nomem;
+	chtls_recv(cdev, &skb, rsp);
+	return 0;
+
+nomem:
+	return 1;
+}
+
+static int do_chtls_getsockopt(struct sock *sk, char __user *optval,
+			       int __user *optlen)
+{
+	struct tls_crypto_info crypto_info;
+
+	crypto_info.version = TLS_1_2_VERSION;
+	if (copy_to_user(optval, &crypto_info, sizeof(struct tls_crypto_info)))
+		return -EFAULT;
+	return 0;
+}
+
+static int chtls_getsockopt(struct sock *sk, int level, int optname,
+			    char __user *optval, int __user *optlen)
+{
+	struct tls_context *ctx = tls_get_ctx(sk);
+
+	if (level != SOL_TLS)
+		return ctx->getsockopt(sk, level, optname, optval, optlen);
+
+	return do_chtls_getsockopt(sk, optval, optlen);
+}
+
+static int do_chtls_setsockopt(struct sock *sk, int optname,
+			       char __user *optval, unsigned int optlen)
+{
+	struct chtls_sock *csk = rcu_dereference_sk_user_data(sk);
+	struct tls_crypto_info *crypto_info, tmp_crypto_info;
+	int keylen;
+	int rc = 0;
+
+	if (!optval || optlen < sizeof(*crypto_info)) {
+		rc = -EINVAL;
+		goto out;
+	}
+
+	rc = copy_from_user(&tmp_crypto_info, optval, sizeof(*crypto_info));
+	if (rc) {
+		rc = -EFAULT;
+		goto out;
+	}
+
+	/* check version */
+	if (tmp_crypto_info.version != TLS_1_2_VERSION) {
+		rc = -ENOTSUPP;
+		goto out;
+	}
+
+	crypto_info = (struct tls_crypto_info *)&csk->tlshws.crypto_info;
+
+	switch (tmp_crypto_info.cipher_type) {
+	case TLS_CIPHER_AES_GCM_128: {
+		rc = copy_from_user(crypto_info, optval,
+				    sizeof(struct
+					   tls12_crypto_info_aes_gcm_128));
+
+		if (rc) {
+			rc = -EFAULT;
+			goto out;
+		}
+
+		keylen = TLS_CIPHER_AES_GCM_128_KEY_SIZE;
+		chtls_setkey(csk, crypto_info, keylen, optname);
+		break;
+	}
+	default:
+		rc = -EINVAL;
+		goto out;
+	}
+out:
+	return rc;
+}
+
+static int chtls_setsockopt(struct sock *sk, int level, int optname,
+			    char __user *optval, unsigned int optlen)
+{
+	struct tls_context *ctx = tls_get_ctx(sk);
+
+	if (level != SOL_TLS)
+		return ctx->setsockopt(sk, level, optname, optval, optlen);
+
+	return do_chtls_setsockopt(sk, optname, optval, optlen);
+}
+
+static int chtls_init(struct sock *sk)
+{
+	struct inet_connection_sock *icsk = inet_csk(sk);
+	struct tls_context *ctx;
+	int rc = 0;
+
+	/* allocate tls context */
+	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+	if (!ctx) {
+		rc = -ENOMEM;
+		goto out;
+	}
+	icsk->icsk_ulp_data = ctx;
+	ctx->setsockopt = sk->sk_prot->setsockopt;
+	ctx->getsockopt = sk->sk_prot->getsockopt;
+	ctx->sk_proto_close = sk->sk_prot->close;
+	sk->sk_prot = &chtls_base_prot;
+out:
+	return rc;
+}
+
+static struct cxgb4_uld_info chtls_uld_info = {
+	.name = DRV_NAME,
+	.nrxq = MAX_ULD_QSETS,
+	.ntxq = MAX_ULD_QSETS,
+	.rxq_size = 1024,
+	.add = chtls_uld_add,
+	.state_change = chtls_uld_state_change,
+	.rx_handler = chtls_uld_rx_handler,
+};
+
+static struct tcp_ulp_ops tcp_chtls_ulp_ops __read_mostly = {
+	.name                   = "chtls",
+	.owner                  = THIS_MODULE,
+	.init                   = chtls_init,
+};
+
+void chtls_install_cpl_ops(struct sock *sk)
+{
+	sk->sk_prot = &chtls_cpl_prot;
+}
+
+static void __init chtls_init_ulp_ops(void)
+{
+	chtls_base_prot			= tcp_prot;
+	chtls_base_prot.hash		= chtls_hash;
+	chtls_base_prot.unhash		= chtls_unhash;
+	chtls_base_prot.close		= chtls_lsk_close;
+
+	chtls_cpl_prot			= chtls_base_prot;
+	chtls_init_rsk_ops(&chtls_cpl_prot, &chtls_rsk_ops,
+			   &tcp_prot, PF_INET);
+	get_tcp_symbol();
+	chtls_cpl_prot.close		= chtls_close;
+	chtls_cpl_prot.disconnect	= chtls_disconnect;
+	chtls_cpl_prot.destroy		= chtls_destroy_sock;
+	chtls_cpl_prot.shutdown		= chtls_shutdown;
+	chtls_cpl_prot.sendmsg		= chtls_sendmsg;
+	chtls_cpl_prot.recvmsg		= chtls_recvmsg;
+	chtls_cpl_prot.sendpage		= chtls_sendpage;
+	chtls_cpl_prot.setsockopt	= chtls_setsockopt;
+	chtls_cpl_prot.getsockopt	= chtls_getsockopt;
+}
+
+static int __init chtls_register(void)
+{
+	chtls_init_ulp_ops();
+	register_listen_notifier(&listen_notifier);
+	cxgb4_register_uld(CXGB4_ULD_TLS, &chtls_uld_info);
+	tcp_register_ulp(&tcp_chtls_ulp_ops);
+	return 0;
+}
+
+static void __exit chtls_unregister(void)
+{
+	unregister_listen_notifier(&listen_notifier);
+	tcp_unregister_ulp(&tcp_chtls_ulp_ops);
+	chtls_free_all_uld();
+	cxgb4_unregister_uld(CXGB4_ULD_TLS);
+}
+
+module_init(chtls_register);
+module_exit(chtls_unregister);
+
+MODULE_DESCRIPTION("Chelsio TLS Inline driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Chelsio Communications");
+MODULE_VERSION(DRV_VERSION);
-- 
1.8.3.1