X-Git-Url: https://git.karo-electronics.de/?a=blobdiff_plain;f=net%2Fdccp%2Fipv4.c;h=4a83978aa660dd9a628bb9134af6bd853de1353d;hb=c9eaf17341834de00351bf79f16b2d879c8aea96;hp=91bffaa761a63b650ac95fe292e6cb75c08d99c1;hpb=d83ca5accb256de1b44835cd222bfdc3207bd7dc;p=mv-sheeva.git diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c index 91bffaa761a..4a83978aa66 100644 --- a/net/dccp/ipv4.c +++ b/net/dccp/ipv4.c @@ -72,7 +72,7 @@ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) tmp = ip_route_connect(&rt, nexthop, inet->saddr, RT_CONN_FLAGS(sk), sk->sk_bound_dev_if, IPPROTO_DCCP, - inet->sport, usin->sin_port, sk); + inet->sport, usin->sin_port, sk, 1); if (tmp < 0) return tmp; @@ -106,20 +106,15 @@ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) goto failure; err = ip_route_newports(&rt, IPPROTO_DCCP, inet->sport, inet->dport, - sk); + sk); if (err != 0) goto failure; /* OK, now commit destination to socket. */ sk_setup_caps(sk, &rt->u.dst); - dp->dccps_gar = - dp->dccps_iss = secure_dccp_sequence_number(inet->saddr, - inet->daddr, - inet->sport, - usin->sin_port); - dccp_update_gss(sk, dp->dccps_iss); - + dp->dccps_iss = secure_dccp_sequence_number(inet->saddr, inet->daddr, + inet->sport, inet->dport); inet->id = dp->dccps_iss ^ jiffies; err = dccp_connect(sk); @@ -162,7 +157,7 @@ static inline void dccp_do_pmtu_discovery(struct sock *sk, /* We don't check in the destentry if pmtu discovery is forbidden * on this route. We just assume that no packet_to_big packets * are send back when pmtu discovery is not active. - * There is a small race when the user changes this flag in the + * There is a small race when the user changes this flag in the * route, but I think that's acceptable. */ if ((dst = __sk_dst_check(sk, 0)) == NULL) @@ -249,7 +244,7 @@ static void dccp_v4_err(struct sk_buff *skb, u32 info) seq = dccp_hdr_seq(skb); if (sk->sk_state != DCCP_LISTEN && !between48(seq, dp->dccps_swl, dp->dccps_swh)) { - NET_INC_STATS(LINUX_MIB_OUTOFWINDOWICMPS); + NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS); goto out; } @@ -349,19 +344,24 @@ out: sock_put(sk); } -/* This routine computes an IPv4 DCCP checksum. */ -void dccp_v4_send_check(struct sock *sk, int len, struct sk_buff *skb) +static inline __sum16 dccp_v4_csum_finish(struct sk_buff *skb, + __be32 src, __be32 dst) +{ + return csum_tcpudp_magic(src, dst, skb->len, IPPROTO_DCCP, skb->csum); +} + +void dccp_v4_send_check(struct sock *sk, int unused, struct sk_buff *skb) { const struct inet_sock *inet = inet_sk(sk); struct dccp_hdr *dh = dccp_hdr(skb); - dh->dccph_checksum = dccp_v4_checksum(skb, inet->saddr, inet->daddr); + dccp_csum_outgoing(skb); + dh->dccph_checksum = dccp_v4_csum_finish(skb, inet->saddr, inet->daddr); } EXPORT_SYMBOL_GPL(dccp_v4_send_check); -static inline u64 dccp_v4_init_sequence(const struct sock *sk, - const struct sk_buff *skb) +static inline u64 dccp_v4_init_sequence(const struct sk_buff *skb) { return secure_dccp_sequence_number(skb->nh.iph->daddr, skb->nh.iph->saddr, @@ -454,47 +454,6 @@ static struct sock *dccp_v4_hnd_req(struct sock *sk, struct sk_buff *skb) return sk; } -int dccp_v4_checksum(const struct sk_buff *skb, const __be32 saddr, - const __be32 daddr) -{ - const struct dccp_hdr* dh = dccp_hdr(skb); - int checksum_len; - u32 tmp; - - if (dh->dccph_cscov == 0) - checksum_len = skb->len; - else { - checksum_len = (dh->dccph_cscov + dh->dccph_x) * sizeof(u32); - checksum_len = checksum_len < skb->len ? checksum_len : - skb->len; - } - - tmp = csum_partial((unsigned char *)dh, checksum_len, 0); - return csum_tcpudp_magic(saddr, daddr, checksum_len, - IPPROTO_DCCP, tmp); -} - -EXPORT_SYMBOL_GPL(dccp_v4_checksum); - -static int dccp_v4_verify_checksum(struct sk_buff *skb, - const __be32 saddr, const __be32 daddr) -{ - struct dccp_hdr *dh = dccp_hdr(skb); - int checksum_len; - u32 tmp; - - if (dh->dccph_cscov == 0) - checksum_len = skb->len; - else { - checksum_len = (dh->dccph_cscov + dh->dccph_x) * sizeof(u32); - checksum_len = checksum_len < skb->len ? checksum_len : - skb->len; - } - tmp = csum_partial((unsigned char *)dh, checksum_len, 0); - return csum_tcpudp_magic(saddr, daddr, checksum_len, - IPPROTO_DCCP, tmp) == 0 ? 0 : -1; -} - static struct dst_entry* dccp_v4_route_skb(struct sock *sk, struct sk_buff *skb) { @@ -508,7 +467,7 @@ static struct dst_entry* dccp_v4_route_skb(struct sock *sk, .uli_u = { .ports = { .sport = dccp_hdr(skb)->dccph_dport, .dport = dccp_hdr(skb)->dccph_sport } - } + } }; security_skb_classify_flow(skb, &fl); @@ -527,7 +486,7 @@ static int dccp_v4_send_response(struct sock *sk, struct request_sock *req, struct sk_buff *skb; /* First, grab a route. */ - + if (dst == NULL && (dst = inet_csk_route_req(sk, req)) == NULL) goto out; @@ -536,14 +495,13 @@ static int dccp_v4_send_response(struct sock *sk, struct request_sock *req, const struct inet_request_sock *ireq = inet_rsk(req); struct dccp_hdr *dh = dccp_hdr(skb); - dh->dccph_checksum = dccp_v4_checksum(skb, ireq->loc_addr, - ireq->rmt_addr); + dh->dccph_checksum = dccp_v4_csum_finish(skb, ireq->loc_addr, + ireq->rmt_addr); memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); err = ip_build_and_send_pkt(skb, sk, ireq->loc_addr, ireq->rmt_addr, ireq->opt); - if (err == NET_XMIT_CN) - err = 0; + err = net_xmit_eval(err); } out: @@ -551,7 +509,7 @@ out: return err; } -static void dccp_v4_ctl_send_reset(struct sk_buff *rxskb) +static void dccp_v4_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb) { int err; struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh; @@ -560,7 +518,7 @@ static void dccp_v4_ctl_send_reset(struct sk_buff *rxskb) sizeof(struct dccp_hdr_reset); struct sk_buff *skb; struct dst_entry *dst; - u64 seqno; + u64 seqno = 0; /* Never send a reset in response to a reset. */ if (rxdh->dccph_type == DCCP_PKT_RESET) @@ -594,16 +552,15 @@ static void dccp_v4_ctl_send_reset(struct sk_buff *rxskb) DCCP_SKB_CB(rxskb)->dccpd_reset_code; /* See "8.3.1. Abnormal Termination" in RFC 4340 */ - seqno = 0; if (DCCP_SKB_CB(rxskb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ) dccp_set_seqno(&seqno, 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_hdr_set_ack(dccp_hdr_ack_bits(skb), DCCP_SKB_CB(rxskb)->dccpd_seq); - dh->dccph_checksum = dccp_v4_checksum(skb, rxskb->nh.iph->saddr, - rxskb->nh.iph->daddr); + dccp_csum_outgoing(skb); + dh->dccph_checksum = dccp_v4_csum_finish(skb, rxskb->nh.iph->saddr, + rxskb->nh.iph->daddr); bh_lock_sock(dccp_v4_ctl_socket->sk); err = ip_build_and_send_pkt(skb, dccp_v4_ctl_socket->sk, @@ -611,7 +568,7 @@ static void dccp_v4_ctl_send_reset(struct sk_buff *rxskb) rxskb->nh.iph->saddr, NULL); bh_unlock_sock(dccp_v4_ctl_socket->sk); - if (err == NET_XMIT_CN || err == 0) { + if (net_xmit_eval(err) == 0) { DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS); DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS); } @@ -638,7 +595,7 @@ int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb) struct inet_request_sock *ireq; struct request_sock *req; struct dccp_request_sock *dreq; - const __be32 service = dccp_hdr_request(skb)->dccph_req_service; + const __be32 service = dccp_hdr_request(skb)->dccph_req_service; struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); __u8 reset_code = DCCP_RESET_CODE_TOO_BUSY; @@ -652,7 +609,7 @@ int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb) if (dccp_bad_service_code(sk, service)) { reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE; goto drop; - } + } /* * TW buckets are converted to open requests without * limitations, they conserve resources and peer is @@ -685,10 +642,9 @@ int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb) ireq = inet_rsk(req); ireq->loc_addr = skb->nh.iph->daddr; ireq->rmt_addr = skb->nh.iph->saddr; - req->rcv_wnd = dccp_feat_default_sequence_window; ireq->opt = NULL; - /* + /* * Step 3: Process LISTEN state * * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie @@ -698,7 +654,7 @@ int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb) */ dreq = dccp_rsk(req); dreq->dreq_isr = dcb->dccpd_seq; - dreq->dreq_iss = dccp_v4_init_sequence(sk, skb); + dreq->dreq_iss = dccp_v4_init_sequence(skb); dreq->dreq_service = service; if (dccp_v4_send_response(sk, req, NULL)) @@ -768,7 +724,7 @@ int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) return 0; reset: - dccp_v4_ctl_send_reset(skb); + dccp_v4_ctl_send_reset(sk, skb); discard: kfree_skb(skb); return 0; @@ -776,60 +732,74 @@ discard: EXPORT_SYMBOL_GPL(dccp_v4_do_rcv); +/** + * dccp_invalid_packet - check for malformed packets + * Implements RFC 4340, 8.5: Step 1: Check header basics + * Packets that fail these checks are ignored and do not receive Resets. + */ int dccp_invalid_packet(struct sk_buff *skb) { const struct dccp_hdr *dh; + unsigned int cscov; if (skb->pkt_type != PACKET_HOST) return 1; + /* If the packet is shorter than 12 bytes, drop packet and return */ if (!pskb_may_pull(skb, sizeof(struct dccp_hdr))) { - LIMIT_NETDEBUG(KERN_WARNING "DCCP: pskb_may_pull failed\n"); + DCCP_WARN("pskb_may_pull failed\n"); return 1; } dh = dccp_hdr(skb); - /* If the packet type is not understood, drop packet and return */ + /* If P.type is not understood, drop packet and return */ if (dh->dccph_type >= DCCP_PKT_INVALID) { - LIMIT_NETDEBUG(KERN_WARNING "DCCP: invalid packet type\n"); + DCCP_WARN("invalid packet type\n"); return 1; } /* - * If P.Data Offset is too small for packet type, or too large for - * packet, drop packet and return + * If P.Data Offset is too small for packet type, drop packet and return */ if (dh->dccph_doff < dccp_hdr_len(skb) / sizeof(u32)) { - LIMIT_NETDEBUG(KERN_WARNING "DCCP: P.Data Offset(%u) " - "too small 1\n", - dh->dccph_doff); + DCCP_WARN("P.Data Offset(%u) too small\n", dh->dccph_doff); return 1; } - + /* + * If P.Data Offset is too too large for packet, drop packet and return + */ if (!pskb_may_pull(skb, dh->dccph_doff * sizeof(u32))) { - LIMIT_NETDEBUG(KERN_WARNING "DCCP: P.Data Offset(%u) " - "too small 2\n", - dh->dccph_doff); + DCCP_WARN("P.Data Offset(%u) too large\n", dh->dccph_doff); return 1; } - dh = dccp_hdr(skb); - /* * If P.type is not Data, Ack, or DataAck and P.X == 0 (the packet * has short sequence numbers), drop packet and return */ - if (dh->dccph_x == 0 && - dh->dccph_type != DCCP_PKT_DATA && - dh->dccph_type != DCCP_PKT_ACK && - dh->dccph_type != DCCP_PKT_DATAACK) { - LIMIT_NETDEBUG(KERN_WARNING "DCCP: P.type (%s) not Data, Ack " - "nor DataAck and P.X == 0\n", - dccp_packet_name(dh->dccph_type)); + if (dh->dccph_type >= DCCP_PKT_DATA && + dh->dccph_type <= DCCP_PKT_DATAACK && dh->dccph_x == 0) { + DCCP_WARN("P.type (%s) not Data || [Data]Ack, while P.X == 0\n", + dccp_packet_name(dh->dccph_type)); + return 1; + } + + /* + * If P.CsCov is too large for the packet size, drop packet and return. + * This must come _before_ checksumming (not as RFC 4340 suggests). + */ + cscov = dccp_csum_coverage(skb); + if (cscov > skb->len) { + DCCP_WARN("P.CsCov %u exceeds packet length %d\n", + dh->dccph_cscov, skb->len); return 1; } + /* If header checksum is incorrect, drop packet and return. + * (This step is completed in the AF-dependent functions.) */ + skb->csum = skb_checksum(skb, 0, cscov, 0); + return 0; } @@ -840,17 +810,16 @@ static int dccp_v4_rcv(struct sk_buff *skb) { const struct dccp_hdr *dh; struct sock *sk; + int min_cov; - /* Step 1: Check header basics: */ + /* Step 1: Check header basics */ if (dccp_invalid_packet(skb)) goto discard_it; - /* If the header checksum is incorrect, drop packet and return */ - if (dccp_v4_verify_checksum(skb, skb->nh.iph->saddr, - skb->nh.iph->daddr) < 0) { - LIMIT_NETDEBUG(KERN_WARNING "%s: incorrect header checksum\n", - __FUNCTION__); + /* Step 1: If header checksum is incorrect, drop packet and return */ + if (dccp_v4_csum_finish(skb, skb->nh.iph->saddr, skb->nh.iph->daddr)) { + DCCP_WARN("dropped packet with invalid checksum\n"); goto discard_it; } @@ -877,15 +846,15 @@ static int dccp_v4_rcv(struct sk_buff *skb) } /* Step 2: - * Look up flow ID in table and get corresponding socket */ + * Look up flow ID in table and get corresponding socket */ sk = __inet_lookup(&dccp_hashinfo, skb->nh.iph->saddr, dh->dccph_sport, skb->nh.iph->daddr, dh->dccph_dport, inet_iif(skb)); - /* + /* * Step 2: - * If no socket ... + * If no socket ... */ if (sk == NULL) { dccp_pr_debug("failed to look up flow ID in table and " @@ -893,9 +862,9 @@ static int dccp_v4_rcv(struct sk_buff *skb) goto no_dccp_socket; } - /* + /* * Step 2: - * ... or S.state == TIMEWAIT, + * ... or S.state == TIMEWAIT, * Generate Reset(No Connection) unless P.type == Reset * Drop packet and return */ @@ -905,25 +874,40 @@ static int dccp_v4_rcv(struct sk_buff *skb) goto no_dccp_socket; } + /* + * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage + * o if MinCsCov = 0, only packets with CsCov = 0 are accepted + * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov + */ + min_cov = dccp_sk(sk)->dccps_pcrlen; + if (dh->dccph_cscov && (min_cov == 0 || dh->dccph_cscov < min_cov)) { + dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n", + dh->dccph_cscov, min_cov); + /* FIXME: "Such packets SHOULD be reported using Data Dropped + * options (Section 11.7) with Drop Code 0, Protocol + * Constraints." */ + goto discard_and_relse; + } + if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) goto discard_and_relse; nf_reset(skb); - return sk_receive_skb(sk, skb); + return sk_receive_skb(sk, skb, 1); no_dccp_socket: if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) goto discard_it; /* * Step 2: - * If no socket ... + * If no socket ... * Generate Reset(No Connection) unless P.type == Reset * Drop packet and return */ if (dh->dccph_type != DCCP_PKT_RESET) { DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_NO_CONNECTION; - dccp_v4_ctl_send_reset(skb); + dccp_v4_ctl_send_reset(sk, skb); } discard_it: