diff options
Diffstat (limited to 'net/dccp')
| -rw-r--r-- | net/dccp/dccp.h | 2 | ||||
| -rw-r--r-- | net/dccp/ipv4.c | 38 | ||||
| -rw-r--r-- | net/dccp/ipv6.c | 39 | ||||
| -rw-r--r-- | net/dccp/output.c | 52 |
4 files changed, 65 insertions, 66 deletions
diff --git a/net/dccp/dccp.h b/net/dccp/dccp.h index a602d9212c64..ee97950d77d1 100644 --- a/net/dccp/dccp.h +++ b/net/dccp/dccp.h @@ -294,6 +294,8 @@ extern unsigned int dccp_poll(struct file *file, struct socket *sock, extern int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); +extern struct sk_buff *dccp_ctl_make_reset(struct socket *ctl, + struct sk_buff *skb); extern int dccp_send_reset(struct sock *sk, enum dccp_reset_codes code); extern void dccp_send_close(struct sock *sk, const int active); extern int dccp_invalid_packet(struct sk_buff *skb); diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c index 58a79c2ae55c..2312b9f4d7af 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, diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c index d954e8319dbd..b7c0f66e2834 100644 --- a/net/dccp/ipv6.c +++ b/net/dccp/ipv6.c @@ -301,50 +301,23 @@ static void dccp_v6_reqsk_destructor(struct request_sock *req) static void dccp_v6_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb) { - struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh; struct ipv6hdr *rxip6h; - const u32 dccp_hdr_reset_len = sizeof(struct dccp_hdr) + - sizeof(struct dccp_hdr_ext) + - sizeof(struct dccp_hdr_reset); struct sk_buff *skb; struct flowi fl; - u64 seqno = 0; - if (rxdh->dccph_type == DCCP_PKT_RESET) + if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET) return; if (!ipv6_unicast_destination(rxskb)) return; - skb = alloc_skb(dccp_v6_ctl_socket->sk->sk_prot->max_header, - GFP_ATOMIC); + skb = dccp_ctl_make_reset(dccp_v6_ctl_socket, rxskb); if (skb == NULL) return; - skb_reserve(skb, dccp_v6_ctl_socket->sk->sk_prot->max_header); - - dh = dccp_zeroed_hdr(skb, dccp_hdr_reset_len); - - /* Swap the send and the receive. */ - 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); rxip6h = ipv6_hdr(rxskb); - dh->dccph_checksum = dccp_v6_csum_finish(skb, &rxip6h->saddr, - &rxip6h->daddr); + dccp_hdr(skb)->dccph_checksum = dccp_v6_csum_finish(skb, &rxip6h->saddr, + &rxip6h->daddr); memset(&fl, 0, sizeof(fl)); ipv6_addr_copy(&fl.fl6_dst, &rxip6h->saddr); @@ -352,8 +325,8 @@ static void dccp_v6_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb) fl.proto = IPPROTO_DCCP; fl.oif = inet6_iif(rxskb); - fl.fl_ip_dport = dh->dccph_dport; - fl.fl_ip_sport = dh->dccph_sport; + fl.fl_ip_dport = dccp_hdr(skb)->dccph_dport; + fl.fl_ip_sport = dccp_hdr(skb)->dccph_sport; security_skb_classify_flow(rxskb, &fl); /* sk = NULL, but it is safe for now. RST socket required. */ diff --git a/net/dccp/output.c b/net/dccp/output.c index f4bde2056204..6a334ed5e9d6 100644 --- a/net/dccp/output.c +++ b/net/dccp/output.c @@ -327,6 +327,58 @@ struct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst, EXPORT_SYMBOL_GPL(dccp_make_response); +/* answer offending packet in @rcv_skb with Reset from control socket @ctl */ +struct sk_buff *dccp_ctl_make_reset(struct socket *ctl, struct sk_buff *rcv_skb) +{ + struct dccp_hdr *rxdh = dccp_hdr(rcv_skb), *dh; + struct dccp_skb_cb *dcb = DCCP_SKB_CB(rcv_skb); + const u32 dccp_hdr_reset_len = sizeof(struct dccp_hdr) + + sizeof(struct dccp_hdr_ext) + + sizeof(struct dccp_hdr_reset); + struct dccp_hdr_reset *dhr; + struct sk_buff *skb; + + skb = alloc_skb(ctl->sk->sk_prot->max_header, GFP_ATOMIC); + if (skb == NULL) + return NULL; + + skb_reserve(skb, ctl->sk->sk_prot->max_header); + + /* Swap the send and the receive. */ + dh = dccp_zeroed_hdr(skb, dccp_hdr_reset_len); + 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; + + dhr = dccp_hdr_reset(skb); + dhr->dccph_reset_code = dcb->dccpd_reset_code; + + switch (dcb->dccpd_reset_code) { + case DCCP_RESET_CODE_PACKET_ERROR: + dhr->dccph_reset_data[0] = rxdh->dccph_type; + break; + case DCCP_RESET_CODE_OPTION_ERROR: /* fall through */ + case DCCP_RESET_CODE_MANDATORY_ERROR: + memcpy(dhr->dccph_reset_data, dcb->dccpd_reset_data, 3); + break; + } + /* + * From RFC 4340, 8.3.1: + * If P.ackno exists, set R.seqno := P.ackno + 1. + * Else set R.seqno := 0. + */ + if (dcb->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ) + dccp_hdr_set_seq(dh, ADD48(dcb->dccpd_ack_seq, 1)); + dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), dcb->dccpd_seq); + + dccp_csum_outgoing(skb); + return skb; +} + +EXPORT_SYMBOL_GPL(dccp_ctl_make_reset); + /* send Reset on established socket, to close or abort the connection */ int dccp_send_reset(struct sock *sk, enum dccp_reset_codes code) { |
