rxrpc: Don't pick values out of the wire header when setting up security

Don't pick values out of the wire header in rxkad when setting up DATA
packet security, but rather use other sources.  This makes it easier to get
rid of txb->wire.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: linux-afs@lists.infradead.org
cc: netdev@vger.kernel.org

net/rxrpc/rxkad.c

@@ -259,7 +259,7 @@ static int rxkad_secure_packet_auth(const struct rxrpc_call *call,
 
 	_enter("");
 
-	check = txb->seq ^ ntohl(txb->wire.callNumber);
+	check = txb->seq ^ call->call_id;
 	hdr->data_size = htonl((u32)check << 16 | txb->len);
 
 	txb->len += sizeof(struct rxkad_level1_hdr);
@@ -302,7 +302,7 @@ static int rxkad_secure_packet_encrypt(const struct rxrpc_call *call,
 
 	_enter("");
 
-	check = txb->seq ^ ntohl(txb->wire.callNumber);
+	check = txb->seq ^ call->call_id;
 
 	rxkhdr->data_size = htonl(txb->len | (u32)check << 16);
 	rxkhdr->checksum = 0;
@@ -362,9 +362,9 @@ static int rxkad_secure_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb)
 	memcpy(&iv, call->conn->rxkad.csum_iv.x, sizeof(iv));
 
 	/* calculate the security checksum */
-	x = (ntohl(txb->wire.cid) & RXRPC_CHANNELMASK) << (32 - RXRPC_CIDSHIFT);
+	x = (call->cid & RXRPC_CHANNELMASK) << (32 - RXRPC_CIDSHIFT);
 	x |= txb->seq & 0x3fffffff;
-	crypto.buf[0] = txb->wire.callNumber;
+	crypto.buf[0] = htonl(call->call_id);
 	crypto.buf[1] = htonl(x);
 
 	sg_init_one(&sg, crypto.buf, 8);