From e356d37a096a990ea1a74c44c15640122e56110b Mon Sep 17 00:00:00 2001 From: Gerrit Renker Date: Wed, 26 Sep 2007 14:35:19 -0300 Subject: [DCCP]: Factor out common code for generating Resets This factors code common to dccp_v{4,6}_ctl_send_reset into a separate function, and adds support for filling in the Data 1 ... Data 3 fields from RFC 4340, 5.6. It is useful to have this separate, since the following Reset codes will always be generated from the control socket rather than via dccp_send_reset: * Code 3, "No Connection", cf. 8.3.1; * Code 4, "Packet Error" (identification for Data 1 added); * Code 5, "Option Error" (identification for Data 1..3 added, will be used later); * Code 6, "Mandatory Error" (same as Option Error); * Code 7, "Connection Refused" (what on Earth is the difference to "No Connection"?); * Code 8, "Bad Service Code"; * Code 9, "Too Busy"; * Code 10, "Bad Init Cookie" (not used). Code 0 is not recommended by the RFC, the following codes would be used in dccp_send_reset() instead, since they all relate to an established DCCP connection: * Code 1, "Closed"; * Code 2, "Aborted"; * Code 11, "Aggression Penalty" (12.3). Signed-off-by: Gerrit Renker Signed-off-by: Arnaldo Carvalho de Melo --- net/dccp/ipv4.c | 38 +++++--------------------------------- 1 file changed, 5 insertions(+), 33 deletions(-) (limited to 'net/dccp/ipv4.c') diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c index 58a79c2ae55..2312b9f4d7a 100644 --- a/net/dccp/ipv4.c +++ b/net/dccp/ipv4.c @@ -510,17 +510,12 @@ out: static void dccp_v4_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb) { int err; - struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh; const struct iphdr *rxiph; - const int dccp_hdr_reset_len = sizeof(struct dccp_hdr) + - sizeof(struct dccp_hdr_ext) + - sizeof(struct dccp_hdr_reset); struct sk_buff *skb; struct dst_entry *dst; - u64 seqno = 0; /* Never send a reset in response to a reset. */ - if (rxdh->dccph_type == DCCP_PKT_RESET) + if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET) return; if (((struct rtable *)rxskb->dst)->rt_type != RTN_LOCAL) @@ -530,37 +525,14 @@ static void dccp_v4_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb) if (dst == NULL) return; - skb = alloc_skb(dccp_v4_ctl_socket->sk->sk_prot->max_header, - GFP_ATOMIC); + skb = dccp_ctl_make_reset(dccp_v4_ctl_socket, rxskb); if (skb == NULL) goto out; - /* Reserve space for headers. */ - skb_reserve(skb, dccp_v4_ctl_socket->sk->sk_prot->max_header); - skb->dst = dst_clone(dst); - - dh = dccp_zeroed_hdr(skb, dccp_hdr_reset_len); - - /* Build DCCP header and checksum it. */ - dh->dccph_type = DCCP_PKT_RESET; - dh->dccph_sport = rxdh->dccph_dport; - dh->dccph_dport = rxdh->dccph_sport; - dh->dccph_doff = dccp_hdr_reset_len / 4; - dh->dccph_x = 1; - dccp_hdr_reset(skb)->dccph_reset_code = - DCCP_SKB_CB(rxskb)->dccpd_reset_code; - - /* See "8.3.1. Abnormal Termination" in RFC 4340 */ - if (DCCP_SKB_CB(rxskb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ) - seqno = ADD48(DCCP_SKB_CB(rxskb)->dccpd_ack_seq, 1); - - dccp_hdr_set_seq(dh, seqno); - dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), DCCP_SKB_CB(rxskb)->dccpd_seq); - - dccp_csum_outgoing(skb); rxiph = ip_hdr(rxskb); - dh->dccph_checksum = dccp_v4_csum_finish(skb, rxiph->saddr, - rxiph->daddr); + dccp_hdr(skb)->dccph_checksum = dccp_v4_csum_finish(skb, rxiph->saddr, + rxiph->daddr); + skb->dst = dst_clone(dst); bh_lock_sock(dccp_v4_ctl_socket->sk); err = ip_build_and_send_pkt(skb, dccp_v4_ctl_socket->sk, -- cgit v1.2.3