tls: create an internal header

include/net/tls.h is getting a little long, and is probably hard
for driver authors to navigate. Split out the internals into a
header which will live under net/tls/. While at it move some
static inlines with a single user into the source files, add
a few tls_ prefixes and fix spelling of 'proccess'.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/tls/tls.h

+/*
+ * Copyright (c) 2016-2017, Mellanox Technologies. All rights reserved.
+ * Copyright (c) 2016-2017, Dave Watson <davejwatson@fb.com>. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef _TLS_INT_H
+#define _TLS_INT_H
+
+#include <asm/byteorder.h>
+#include <linux/types.h>
+#include <linux/skmsg.h>
+#include <net/tls.h>
+
+#define __TLS_INC_STATS(net, field)				\
+	__SNMP_INC_STATS((net)->mib.tls_statistics, field)
+#define TLS_INC_STATS(net, field)				\
+	SNMP_INC_STATS((net)->mib.tls_statistics, field)
+#define TLS_DEC_STATS(net, field)				\
+	SNMP_DEC_STATS((net)->mib.tls_statistics, field)
+
+/* TLS records are maintained in 'struct tls_rec'. It stores the memory pages
+ * allocated or mapped for each TLS record. After encryption, the records are
+ * stores in a linked list.
+ */
+struct tls_rec {
+	struct list_head list;
+	int tx_ready;
+	int tx_flags;
+
+	struct sk_msg msg_plaintext;
+	struct sk_msg msg_encrypted;
+
+	/* AAD | msg_plaintext.sg.data | sg_tag */
+	struct scatterlist sg_aead_in[2];
+	/* AAD | msg_encrypted.sg.data (data contains overhead for hdr & iv & tag) */
+	struct scatterlist sg_aead_out[2];
+
+	char content_type;
+	struct scatterlist sg_content_type;
+
+	char aad_space[TLS_AAD_SPACE_SIZE];
+	u8 iv_data[MAX_IV_SIZE];
+	struct aead_request aead_req;
+	u8 aead_req_ctx[];
+};
+
+int __net_init tls_proc_init(struct net *net);
+void __net_exit tls_proc_fini(struct net *net);
+
+struct tls_context *tls_ctx_create(struct sock *sk);
+void tls_ctx_free(struct sock *sk, struct tls_context *ctx);
+void update_sk_prot(struct sock *sk, struct tls_context *ctx);
+
+int wait_on_pending_writer(struct sock *sk, long *timeo);
+int tls_sk_query(struct sock *sk, int optname, char __user *optval,
+		 int __user *optlen);
+int tls_sk_attach(struct sock *sk, int optname, char __user *optval,
+		  unsigned int optlen);
+void tls_err_abort(struct sock *sk, int err);
+
+int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx);
+void tls_update_rx_zc_capable(struct tls_context *tls_ctx);
+void tls_sw_strparser_arm(struct sock *sk, struct tls_context *ctx);
+void tls_sw_strparser_done(struct tls_context *tls_ctx);
+int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size);
+int tls_sw_sendpage_locked(struct sock *sk, struct page *page,
+			   int offset, size_t size, int flags);
+int tls_sw_sendpage(struct sock *sk, struct page *page,
+		    int offset, size_t size, int flags);
+void tls_sw_cancel_work_tx(struct tls_context *tls_ctx);
+void tls_sw_release_resources_tx(struct sock *sk);
+void tls_sw_free_ctx_tx(struct tls_context *tls_ctx);
+void tls_sw_free_resources_rx(struct sock *sk);
+void tls_sw_release_resources_rx(struct sock *sk);
+void tls_sw_free_ctx_rx(struct tls_context *tls_ctx);
+int tls_sw_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
+		   int flags, int *addr_len);
+bool tls_sw_sock_is_readable(struct sock *sk);
+ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos,
+			   struct pipe_inode_info *pipe,
+			   size_t len, unsigned int flags);
+
+int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size);
+int tls_device_sendpage(struct sock *sk, struct page *page,
+			int offset, size_t size, int flags);
+int tls_tx_records(struct sock *sk, int flags);
+
+void tls_sw_write_space(struct sock *sk, struct tls_context *ctx);
+void tls_device_write_space(struct sock *sk, struct tls_context *ctx);
+
+int tls_process_cmsg(struct sock *sk, struct msghdr *msg,
+		     unsigned char *record_type);
+int decrypt_skb(struct sock *sk, struct sk_buff *skb,
+		struct scatterlist *sgout);
+
+int tls_sw_fallback_init(struct sock *sk,
+			 struct tls_offload_context_tx *offload_ctx,
+			 struct tls_crypto_info *crypto_info);
+
+static inline struct tls_msg *tls_msg(struct sk_buff *skb)
+{
+	struct sk_skb_cb *scb = (struct sk_skb_cb *)skb->cb;
+
+	return &scb->tls;
+}
+
+#ifdef CONFIG_TLS_DEVICE
+void tls_device_init(void);
+void tls_device_cleanup(void);
+int tls_set_device_offload(struct sock *sk, struct tls_context *ctx);
+void tls_device_free_resources_tx(struct sock *sk);
+int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx);
+void tls_device_offload_cleanup_rx(struct sock *sk);
+void tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq);
+int tls_device_decrypted(struct sock *sk, struct tls_context *tls_ctx,
+			 struct sk_buff *skb, struct strp_msg *rxm);
+#else
+static inline void tls_device_init(void) {}
+static inline void tls_device_cleanup(void) {}
+
+static inline int
+tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline void tls_device_free_resources_tx(struct sock *sk) {}
+
+static inline int
+tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline void tls_device_offload_cleanup_rx(struct sock *sk) {}
+static inline void
+tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq) {}
+
+static inline int
+tls_device_decrypted(struct sock *sk, struct tls_context *tls_ctx,
+		     struct sk_buff *skb, struct strp_msg *rxm)
+{
+	return 0;
+}
+#endif
+
+int tls_push_sg(struct sock *sk, struct tls_context *ctx,
+		struct scatterlist *sg, u16 first_offset,
+		int flags);
+int tls_push_partial_record(struct sock *sk, struct tls_context *ctx,
+			    int flags);
+void tls_free_partial_record(struct sock *sk, struct tls_context *ctx);
+
+static inline bool tls_is_partially_sent_record(struct tls_context *ctx)
+{
+	return !!ctx->partially_sent_record;
+}
+
+static inline bool tls_is_pending_open_record(struct tls_context *tls_ctx)
+{
+	return tls_ctx->pending_open_record_frags;
+}
+
+static inline bool tls_bigint_increment(unsigned char *seq, int len)
+{
+	int i;
+
+	for (i = len - 1; i >= 0; i--) {
+		++seq[i];
+		if (seq[i] != 0)
+			break;
+	}
+
+	return (i == -1);
+}
+
+static inline void tls_bigint_subtract(unsigned char *seq, int  n)
+{
+	u64 rcd_sn;
+	__be64 *p;
+
+	BUILD_BUG_ON(TLS_MAX_REC_SEQ_SIZE != 8);
+
+	p = (__be64 *)seq;
+	rcd_sn = be64_to_cpu(*p);
+	*p = cpu_to_be64(rcd_sn - n);
+}
+
+static inline void
+tls_advance_record_sn(struct sock *sk, struct tls_prot_info *prot,
+		      struct cipher_context *ctx)
+{
+	if (tls_bigint_increment(ctx->rec_seq, prot->rec_seq_size))
+		tls_err_abort(sk, -EBADMSG);
+
+	if (prot->version != TLS_1_3_VERSION &&
+	    prot->cipher_type != TLS_CIPHER_CHACHA20_POLY1305)
+		tls_bigint_increment(ctx->iv + prot->salt_size,
+				     prot->iv_size);
+}
+
+static inline void
+tls_xor_iv_with_seq(struct tls_prot_info *prot, char *iv, char *seq)
+{
+	int i;
+
+	if (prot->version == TLS_1_3_VERSION ||
+	    prot->cipher_type == TLS_CIPHER_CHACHA20_POLY1305) {
+		for (i = 0; i < 8; i++)
+			iv[i + 4] ^= seq[i];
+	}
+}
+
+static inline void
+tls_fill_prepend(struct tls_context *ctx, char *buf, size_t plaintext_len,
+		 unsigned char record_type)
+{
+	struct tls_prot_info *prot = &ctx->prot_info;
+	size_t pkt_len, iv_size = prot->iv_size;
+
+	pkt_len = plaintext_len + prot->tag_size;
+	if (prot->version != TLS_1_3_VERSION &&
+	    prot->cipher_type != TLS_CIPHER_CHACHA20_POLY1305) {
+		pkt_len += iv_size;
+
+		memcpy(buf + TLS_NONCE_OFFSET,
+		       ctx->tx.iv + prot->salt_size, iv_size);
+	}
+
+	/* we cover nonce explicit here as well, so buf should be of
+	 * size KTLS_DTLS_HEADER_SIZE + KTLS_DTLS_NONCE_EXPLICIT_SIZE
+	 */
+	buf[0] = prot->version == TLS_1_3_VERSION ?
+		   TLS_RECORD_TYPE_DATA : record_type;
+	/* Note that VERSION must be TLS_1_2 for both TLS1.2 and TLS1.3 */
+	buf[1] = TLS_1_2_VERSION_MINOR;
+	buf[2] = TLS_1_2_VERSION_MAJOR;
+	/* we can use IV for nonce explicit according to spec */
+	buf[3] = pkt_len >> 8;
+	buf[4] = pkt_len & 0xFF;
+}
+
+static inline
+void tls_make_aad(char *buf, size_t size, char *record_sequence,
+		  unsigned char record_type, struct tls_prot_info *prot)
+{
+	if (prot->version != TLS_1_3_VERSION) {
+		memcpy(buf, record_sequence, prot->rec_seq_size);
+		buf += 8;
+	} else {
+		size += prot->tag_size;
+	}
+
+	buf[0] = prot->version == TLS_1_3_VERSION ?
+		  TLS_RECORD_TYPE_DATA : record_type;
+	buf[1] = TLS_1_2_VERSION_MAJOR;
+	buf[2] = TLS_1_2_VERSION_MINOR;
+	buf[3] = size >> 8;
+	buf[4] = size & 0xFF;
+}
+
+#endif

net/tls/tls_device.c

@@ -38,6 +38,7 @@
 #include <net/tcp.h>
 #include <net/tls.h>
 
+#include "tls.h"
 #include "trace.h"
 
 /* device_offload_lock is used to synchronize tls_dev_add
@@ -562,7 +563,7 @@ int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
 	lock_sock(sk);
 
 	if (unlikely(msg->msg_controllen)) {
-		rc = tls_proccess_cmsg(sk, msg, &record_type);
+		rc = tls_process_cmsg(sk, msg, &record_type);
 		if (rc)
 			goto out;
 	}

net/tls/tls_device_fallback.c

@@ -34,6 +34,8 @@
 #include <crypto/scatterwalk.h>
 #include <net/ip6_checksum.h>
 
+#include "tls.h"
+
 static void chain_to_walk(struct scatterlist *sg, struct scatter_walk *walk)
 {
 	struct scatterlist *src = walk->sg;

net/tls/tls_main.c

@@ -45,6 +45,8 @@
 #include <net/tls.h>
 #include <net/tls_toe.h>
 
+#include "tls.h"
+
 MODULE_AUTHOR("Mellanox Technologies");
 MODULE_DESCRIPTION("Transport Layer Security Support");
 MODULE_LICENSE("Dual BSD/GPL");
@@ -164,7 +166,7 @@ static int tls_handle_open_record(struct sock *sk, int flags)
 	return 0;
 }
 
-int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg,
+int tls_process_cmsg(struct sock *sk, struct msghdr *msg,
 		     unsigned char *record_type)
 {
 	struct cmsghdr *cmsg;
@@ -1003,6 +1005,23 @@ static void tls_update(struct sock *sk, struct proto *p,
 	}
 }
 
+static u16 tls_user_config(struct tls_context *ctx, bool tx)
+{
+	u16 config = tx ? ctx->tx_conf : ctx->rx_conf;
+
+	switch (config) {
+	case TLS_BASE:
+		return TLS_CONF_BASE;
+	case TLS_SW:
+		return TLS_CONF_SW;
+	case TLS_HW:
+		return TLS_CONF_HW;
+	case TLS_HW_RECORD:
+		return TLS_CONF_HW_RECORD;
+	}
+	return 0;
+}
+
 static int tls_get_info(const struct sock *sk, struct sk_buff *skb)
 {
 	u16 version, cipher_type;

net/tls/tls_proc.c

@@ -6,6 +6,8 @@
 #include <net/snmp.h>
 #include <net/tls.h>
 
+#include "tls.h"
+
 #ifdef CONFIG_PROC_FS
 static const struct snmp_mib tls_mib_list[] = {
 	SNMP_MIB_ITEM("TlsCurrTxSw", LINUX_MIB_TLSCURRTXSW),

net/tls/tls_sw.c

@@ -44,6 +44,8 @@
 #include <net/strparser.h>
 #include <net/tls.h>
 
+#include "tls.h"
+
 struct tls_decrypt_arg {
 	bool zc;
 	bool async;
@@ -524,7 +526,8 @@ static int tls_do_encryption(struct sock *sk,
 	memcpy(&rec->iv_data[iv_offset], tls_ctx->tx.iv,
 	       prot->iv_size + prot->salt_size);
 
-	xor_iv_with_seq(prot, rec->iv_data + iv_offset, tls_ctx->tx.rec_seq);
+	tls_xor_iv_with_seq(prot, rec->iv_data + iv_offset,
+			    tls_ctx->tx.rec_seq);
 
 	sge->offset += prot->prepend_size;
 	sge->length -= prot->prepend_size;
@@ -961,7 +964,7 @@ int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
 	lock_sock(sk);
 
 	if (unlikely(msg->msg_controllen)) {
-		ret = tls_proccess_cmsg(sk, msg, &record_type);
+		ret = tls_process_cmsg(sk, msg, &record_type);
 		if (ret) {
 			if (ret == -EINPROGRESS)
 				num_async++;
@@ -1495,7 +1498,7 @@ static int decrypt_internal(struct sock *sk, struct sk_buff *skb,
 			goto exit_free;
 		memcpy(&dctx->iv[iv_offset], tls_ctx->rx.iv, prot->salt_size);
 	}
-	xor_iv_with_seq(prot, &dctx->iv[iv_offset], tls_ctx->rx.rec_seq);
+	tls_xor_iv_with_seq(prot, &dctx->iv[iv_offset], tls_ctx->rx.rec_seq);
 
 	/* Prepare AAD */
 	tls_make_aad(dctx->aad, rxm->full_len - prot->overhead_size +
@@ -2267,12 +2270,23 @@ static void tx_work_handler(struct work_struct *work)
 	mutex_unlock(&tls_ctx->tx_lock);
 }
 
+static bool tls_is_tx_ready(struct tls_sw_context_tx *ctx)
+{
+	struct tls_rec *rec;
+
+	rec = list_first_entry(&ctx->tx_list, struct tls_rec, list);
+	if (!rec)
+		return false;
+
+	return READ_ONCE(rec->tx_ready);
+}
+
 void tls_sw_write_space(struct sock *sk, struct tls_context *ctx)
 {
 	struct tls_sw_context_tx *tx_ctx = tls_sw_ctx_tx(ctx);
 
 	/* Schedule the transmission if tx list is ready */
-	if (is_tx_ready(tx_ctx) &&
+	if (tls_is_tx_ready(tx_ctx) &&
 	    !test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx->tx_bitmask))
 		schedule_delayed_work(&tx_ctx->tx_work.work, 0);
 }

net/tls/tls_toe.c

@@ -38,6 +38,8 @@
 #include <net/tls.h>
 #include <net/tls_toe.h>
 
+#include "tls.h"
+
 static LIST_HEAD(device_list);
 static DEFINE_SPINLOCK(device_spinlock);