net: Eliminate no_check from protosw

It doesn't seem like an protocols are setting anything other
than the default, and allowing to arbitrarily disable checksums
for a whole protocol seems dangerous. This can be done on a per
socket basis.

Signed-off-by: Tom Herbert <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

include/net/protocol.h

···
 	struct proto	 *prot;
 	const struct proto_ops *ops;
   
-	char             no_check;   /* checksum on rcv/xmit/none? */
 	unsigned char	 flags;      /* See INET_PROTOSW_* below.  */
 };
 #define INET_PROTOSW_REUSE 0x01	     /* Are ports automatically reusable? */

net/dccp/ipv4.c

···
 	.protocol	= IPPROTO_DCCP,
 	.prot		= &dccp_v4_prot,
 	.ops		= &inet_dccp_ops,
-	.no_check	= 0,
 	.flags		= INET_PROTOSW_ICSK,
 };
 

net/ipv4/af_inet.c

···
 	struct inet_sock *inet;
 	struct proto *answer_prot;
 	unsigned char answer_flags;
-	char answer_no_check;
 	int try_loading_module = 0;
 	int err;
 
···
 
 	sock->ops = answer->ops;
 	answer_prot = answer->prot;
-	answer_no_check = answer->no_check;
 	answer_flags = answer->flags;
 	rcu_read_unlock();
 
···
 		goto out;
 
 	err = 0;
-	sk->sk_no_check = answer_no_check;
 	if (INET_PROTOSW_REUSE & answer_flags)
 		sk->sk_reuse = SK_CAN_REUSE;
 
···
 		.protocol =   IPPROTO_TCP,
 		.prot =       &tcp_prot,
 		.ops =        &inet_stream_ops,
-		.no_check =   0,
 		.flags =      INET_PROTOSW_PERMANENT |
 			      INET_PROTOSW_ICSK,
 	},
···
 		.protocol =   IPPROTO_UDP,
 		.prot =       &udp_prot,
 		.ops =        &inet_dgram_ops,
-		.no_check =   UDP_CSUM_DEFAULT,
 		.flags =      INET_PROTOSW_PERMANENT,
        },
 
···
 		.protocol =   IPPROTO_ICMP,
 		.prot =       &ping_prot,
 		.ops =        &inet_dgram_ops,
-		.no_check =   UDP_CSUM_DEFAULT,
 		.flags =      INET_PROTOSW_REUSE,
        },
 
···
 	       .protocol =   IPPROTO_IP,	/* wild card */
 	       .prot =       &raw_prot,
 	       .ops =        &inet_sockraw_ops,
-	       .no_check =   UDP_CSUM_DEFAULT,
 	       .flags =      INET_PROTOSW_REUSE,
        }
 };

net/ipv4/udplite.c

···
 	.protocol	=  IPPROTO_UDPLITE,
 	.prot		=  &udplite_prot,
 	.ops		=  &inet_dgram_ops,
-	.no_check	=  0,		/* must checksum (RFC 3828) */
 	.flags		=  INET_PROTOSW_PERMANENT,
 };
 

net/ipv6/af_inet6.c

···
 	struct inet_protosw *answer;
 	struct proto *answer_prot;
 	unsigned char answer_flags;
-	char answer_no_check;
 	int try_loading_module = 0;
 	int err;
 
···
 
 	sock->ops = answer->ops;
 	answer_prot = answer->prot;
-	answer_no_check = answer->no_check;
 	answer_flags = answer->flags;
 	rcu_read_unlock();
 
···
 	sock_init_data(sock, sk);
 
 	err = 0;
-	sk->sk_no_check = answer_no_check;
 	if (INET_PROTOSW_REUSE & answer_flags)
 		sk->sk_reuse = SK_CAN_REUSE;
 

net/ipv6/ping.c

···
 	.protocol =  IPPROTO_ICMPV6,
 	.prot =      &pingv6_prot,
 	.ops =       &inet6_dgram_ops,
-	.no_check =  UDP_CSUM_DEFAULT,
 	.flags =     INET_PROTOSW_REUSE,
 };
 

net/ipv6/raw.c

···
 	.protocol	= IPPROTO_IP,	/* wild card */
 	.prot		= &rawv6_prot,
 	.ops		= &inet6_sockraw_ops,
-	.no_check	= UDP_CSUM_DEFAULT,
 	.flags		= INET_PROTOSW_REUSE,
 };
 

net/ipv6/tcp_ipv6.c

···
 	.protocol	=	IPPROTO_TCP,
 	.prot		=	&tcpv6_prot,
 	.ops		=	&inet6_stream_ops,
-	.no_check	=	0,
 	.flags		=	INET_PROTOSW_PERMANENT |
 				INET_PROTOSW_ICSK,
 };

net/ipv6/udp.c

···
 	.protocol =  IPPROTO_UDP,
 	.prot =      &udpv6_prot,
 	.ops =       &inet6_dgram_ops,
-	.no_check =  UDP_CSUM_DEFAULT,
 	.flags =     INET_PROTOSW_PERMANENT,
 };
 

net/ipv6/udplite.c

···
 	.protocol	= IPPROTO_UDPLITE,
 	.prot		= &udplitev6_prot,
 	.ops		= &inet6_dgram_ops,
-	.no_check	= 0,
 	.flags		= INET_PROTOSW_PERMANENT,
 };
 

net/l2tp/l2tp_ip.c

···
 	.protocol	= IPPROTO_L2TP,
 	.prot		= &l2tp_ip_prot,
 	.ops		= &l2tp_ip_ops,
-	.no_check	= 0,
 };
 
 static struct net_protocol l2tp_ip_protocol __read_mostly = {

net/l2tp/l2tp_ip6.c

···
 	.protocol	= IPPROTO_L2TP,
 	.prot		= &l2tp_ip6_prot,
 	.ops		= &l2tp_ip6_ops,
-	.no_check	= 0,
 };
 
 static struct inet6_protocol l2tp_ip6_protocol __read_mostly = {

net/sctp/ipv6.c

···
 	.protocol      = IPPROTO_SCTP,
 	.prot 	       = &sctpv6_prot,
 	.ops           = &inet6_seqpacket_ops,
-	.no_check      = 0,
 	.flags         = SCTP_PROTOSW_FLAG
 };
 static struct inet_protosw sctpv6_stream_protosw = {
···
 	.protocol      = IPPROTO_SCTP,
 	.prot 	       = &sctpv6_prot,
 	.ops           = &inet6_seqpacket_ops,
-	.no_check      = 0,
 	.flags         = SCTP_PROTOSW_FLAG,
 };
 

net/sctp/protocol.c

···
 	.protocol   = IPPROTO_SCTP,
 	.prot       = &sctp_prot,
 	.ops        = &inet_seqpacket_ops,
-	.no_check   = 0,
 	.flags      = SCTP_PROTOSW_FLAG
 };
 static struct inet_protosw sctp_stream_protosw = {
···
 	.protocol   = IPPROTO_SCTP,
 	.prot       = &sctp_prot,
 	.ops        = &inet_seqpacket_ops,
-	.no_check   = 0,
 	.flags      = SCTP_PROTOSW_FLAG
 };