tls: rx: wrap decryption arguments in a structure

We pass zc as a pointer to bool a few functions down as an in/out
argument. This is error prone since C will happily evalue a pointer
as a boolean (IOW forgetting *zc and writing zc leads to loss of
developer time..). Wrap the arguments into a structure.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/tls/tls_sw.c

@@ -44,6 +44,11 @@
 #include <net/strparser.h>
 #include <net/tls.h>
 
+struct tls_decrypt_arg {
+	bool zc;
+	bool async;
+};
+
 noinline void tls_err_abort(struct sock *sk, int err)
 {
 	WARN_ON_ONCE(err >= 0);
@@ -1412,7 +1417,7 @@ static int tls_setup_from_iter(struct iov_iter *from,
 static int decrypt_internal(struct sock *sk, struct sk_buff *skb,
 			    struct iov_iter *out_iov,
 			    struct scatterlist *out_sg,
-			    bool *zc, bool async)
+			    struct tls_decrypt_arg *darg)
 {
 	struct tls_context *tls_ctx = tls_get_ctx(sk);
 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
@@ -1429,7 +1434,7 @@ static int decrypt_internal(struct sock *sk, struct sk_buff *skb,
 			     prot->tail_size;
 	int iv_offset = 0;
 
-	if (*zc && (out_iov || out_sg)) {
+	if (darg->zc && (out_iov || out_sg)) {
 		if (out_iov)
 			n_sgout = 1 +
 				iov_iter_npages_cap(out_iov, INT_MAX, data_len);
@@ -1439,7 +1444,7 @@ static int decrypt_internal(struct sock *sk, struct sk_buff *skb,
 				 rxm->full_len - prot->prepend_size);
 	} else {
 		n_sgout = 0;
-		*zc = false;
+		darg->zc = false;
 		n_sgin = skb_cow_data(skb, 0, &unused);
 	}
 
@@ -1535,12 +1540,12 @@ static int decrypt_internal(struct sock *sk, struct sk_buff *skb,
 fallback_to_reg_recv:
 		sgout = sgin;
 		pages = 0;
-		*zc = false;
+		darg->zc = false;
 	}
 
 	/* Prepare and submit AEAD request */
 	err = tls_do_decryption(sk, skb, sgin, sgout, iv,
-				data_len, aead_req, async);
+				data_len, aead_req, darg->async);
 	if (err == -EINPROGRESS)
 		return err;
 
@@ -1553,7 +1558,8 @@ static int decrypt_internal(struct sock *sk, struct sk_buff *skb,
 }
 
 static int decrypt_skb_update(struct sock *sk, struct sk_buff *skb,
-			      struct iov_iter *dest, bool *zc, bool async)
+			      struct iov_iter *dest,
+			      struct tls_decrypt_arg *darg)
 {
 	struct tls_context *tls_ctx = tls_get_ctx(sk);
 	struct tls_prot_info *prot = &tls_ctx->prot_info;
@@ -1562,7 +1568,7 @@ static int decrypt_skb_update(struct sock *sk, struct sk_buff *skb,
 	int pad, err;
 
 	if (tlm->decrypted) {
-		*zc = false;
+		darg->zc = false;
 		return 0;
 	}
 
@@ -1572,12 +1578,12 @@ static int decrypt_skb_update(struct sock *sk, struct sk_buff *skb,
 			return err;
 		if (err > 0) {
 			tlm->decrypted = 1;
-			*zc = false;
+			darg->zc = false;
 			goto decrypt_done;
 		}
 	}
 
-	err = decrypt_internal(sk, skb, dest, NULL, zc, async);
+	err = decrypt_internal(sk, skb, dest, NULL, darg);
 	if (err < 0) {
 		if (err == -EINPROGRESS)
 			tls_advance_record_sn(sk, prot, &tls_ctx->rx);
@@ -1603,9 +1609,9 @@ static int decrypt_skb_update(struct sock *sk, struct sk_buff *skb,
 int decrypt_skb(struct sock *sk, struct sk_buff *skb,
 		struct scatterlist *sgout)
 {
-	bool zc = true;
+	struct tls_decrypt_arg darg = { .zc = true, };
 
-	return decrypt_internal(sk, skb, NULL, sgout, &zc, false);
+	return decrypt_internal(sk, skb, NULL, sgout, &darg);
 }
 
 static bool tls_sw_advance_skb(struct sock *sk, struct sk_buff *skb,
@@ -1794,11 +1800,10 @@ int tls_sw_recvmsg(struct sock *sk,
 	decrypted = 0;
 	num_async = 0;
 	while (len && (decrypted + copied < target || ctx->recv_pkt)) {
+		struct tls_decrypt_arg darg = {};
 		bool retain_skb = false;
 		int to_decrypt, chunk;
-		bool zc = false;
-		bool async_capable;
-		bool async = false;
+		bool async;
 
 		skb = tls_wait_data(sk, psock, flags & MSG_DONTWAIT, timeo, &err);
 		if (!skb) {
@@ -1824,16 +1829,15 @@ int tls_sw_recvmsg(struct sock *sk,
 		    tlm->control == TLS_RECORD_TYPE_DATA &&
 		    prot->version != TLS_1_3_VERSION &&
 		    !bpf_strp_enabled)
-			zc = true;
+			darg.zc = true;
 
 		/* Do not use async mode if record is non-data */
 		if (tlm->control == TLS_RECORD_TYPE_DATA && !bpf_strp_enabled)
-			async_capable = ctx->async_capable;
+			darg.async = ctx->async_capable;
 		else
-			async_capable = false;
+			darg.async = false;
 
-		err = decrypt_skb_update(sk, skb, &msg->msg_iter,
-					 &zc, async_capable);
+		err = decrypt_skb_update(sk, skb, &msg->msg_iter, &darg);
 		if (err < 0 && err != -EINPROGRESS) {
 			tls_err_abort(sk, -EBADMSG);
 			goto recv_end;
@@ -1879,7 +1883,7 @@ int tls_sw_recvmsg(struct sock *sk,
 		/* TLS 1.3 may have updated the length by more than overhead */
 		chunk = rxm->full_len;
 
-		if (!zc) {
+		if (!darg.zc) {
 			if (bpf_strp_enabled) {
 				err = sk_psock_tls_strp_read(psock, skb);
 				if (err != __SK_PASS) {
@@ -1996,7 +2000,6 @@ ssize_t tls_sw_splice_read(struct socket *sock,  loff_t *ppos,
 	int err = 0;
 	long timeo;
 	int chunk;
-	bool zc = false;
 
 	lock_sock(sk);
 
@@ -2006,12 +2009,14 @@ ssize_t tls_sw_splice_read(struct socket *sock,  loff_t *ppos,
 	if (from_queue) {
 		skb = __skb_dequeue(&ctx->rx_list);
 	} else {
+		struct tls_decrypt_arg darg = {};
+
 		skb = tls_wait_data(sk, NULL, flags & SPLICE_F_NONBLOCK, timeo,
 				    &err);
 		if (!skb)
 			goto splice_read_end;
 
-		err = decrypt_skb_update(sk, skb, NULL, &zc, false);
+		err = decrypt_skb_update(sk, skb, NULL, &darg);
 		if (err < 0) {
 			tls_err_abort(sk, -EBADMSG);
 			goto splice_read_end;