diff options
Diffstat (limited to 'net/phonet/af_phonet.c')
| -rw-r--r-- | net/phonet/af_phonet.c | 96 |
1 files changed, 92 insertions, 4 deletions
diff --git a/net/phonet/af_phonet.c b/net/phonet/af_phonet.c index 50dc258d5aa2..1d8df6b7e3df 100644 --- a/net/phonet/af_phonet.c +++ b/net/phonet/af_phonet.c @@ -132,7 +132,7 @@ EXPORT_SYMBOL(phonet_header_ops); * Prepends an ISI header and sends a datagram. */ static int pn_send(struct sk_buff *skb, struct net_device *dev, - u16 dst, u16 src, u8 res) + u16 dst, u16 src, u8 res, u8 irq) { struct phonethdr *ph; int err; @@ -163,7 +163,10 @@ static int pn_send(struct sk_buff *skb, struct net_device *dev, skb_reset_mac_header(skb); skb->pkt_type = PACKET_LOOPBACK; skb_orphan(skb); - netif_rx_ni(skb); + if (irq) + netif_rx(skb); + else + netif_rx_ni(skb); err = 0; } else { err = dev_hard_header(skb, dev, ntohs(skb->protocol), @@ -181,6 +184,19 @@ drop: return err; } +static int pn_raw_send(const void *data, int len, struct net_device *dev, + u16 dst, u16 src, u8 res) +{ + struct sk_buff *skb = alloc_skb(MAX_PHONET_HEADER + len, GFP_ATOMIC); + if (skb == NULL) + return -ENOMEM; + + skb_reserve(skb, MAX_PHONET_HEADER); + __skb_put(skb, len); + skb_copy_to_linear_data(skb, data, len); + return pn_send(skb, dev, dst, src, res, 1); +} + /* * Create a Phonet header for the skb and send it out. Returns * non-zero error code if failed. The skb is freed then. @@ -211,7 +227,7 @@ int pn_skb_send(struct sock *sk, struct sk_buff *skb, src = pn_object(saddr, pn_obj(src)); err = pn_send(skb, dev, pn_sockaddr_get_object(target), - src, pn_sockaddr_get_resource(target)); + src, pn_sockaddr_get_resource(target), 0); dev_put(dev); return err; @@ -223,6 +239,73 @@ drop: } EXPORT_SYMBOL(pn_skb_send); +/* Do not send an error message in response to an error message */ +static inline int can_respond(struct sk_buff *skb) +{ + const struct phonethdr *ph; + const struct phonetmsg *pm; + u8 submsg_id; + + if (!pskb_may_pull(skb, 3)) + return 0; + + ph = pn_hdr(skb); + if (phonet_address_get(skb->dev, ph->pn_rdev) != ph->pn_rdev) + return 0; /* we are not the destination */ + if (ph->pn_res == PN_PREFIX && !pskb_may_pull(skb, 5)) + return 0; + + ph = pn_hdr(skb); /* re-acquires the pointer */ + pm = pn_msg(skb); + if (pm->pn_msg_id != PN_COMMON_MESSAGE) + return 1; + submsg_id = (ph->pn_res == PN_PREFIX) + ? pm->pn_e_submsg_id : pm->pn_submsg_id; + if (submsg_id != PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP && + pm->pn_e_submsg_id != PN_COMM_SERVICE_NOT_IDENTIFIED_RESP) + return 1; + return 0; +} + +static int send_obj_unreachable(struct sk_buff *rskb) +{ + const struct phonethdr *oph = pn_hdr(rskb); + const struct phonetmsg *opm = pn_msg(rskb); + struct phonetmsg resp; + + memset(&resp, 0, sizeof(resp)); + resp.pn_trans_id = opm->pn_trans_id; + resp.pn_msg_id = PN_COMMON_MESSAGE; + if (oph->pn_res == PN_PREFIX) { + resp.pn_e_res_id = opm->pn_e_res_id; + resp.pn_e_submsg_id = PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP; + resp.pn_e_orig_msg_id = opm->pn_msg_id; + resp.pn_e_status = 0; + } else { + resp.pn_submsg_id = PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP; + resp.pn_orig_msg_id = opm->pn_msg_id; + resp.pn_status = 0; + } + return pn_raw_send(&resp, sizeof(resp), rskb->dev, + pn_object(oph->pn_sdev, oph->pn_sobj), + pn_object(oph->pn_rdev, oph->pn_robj), + oph->pn_res); +} + +static int send_reset_indications(struct sk_buff *rskb) +{ + struct phonethdr *oph = pn_hdr(rskb); + static const u8 data[4] = { + 0x00 /* trans ID */, 0x10 /* subscribe msg */, + 0x00 /* subscription count */, 0x00 /* dummy */ + }; + + return pn_raw_send(data, sizeof(data), rskb->dev, + pn_object(oph->pn_sdev, 0x00), + pn_object(oph->pn_rdev, oph->pn_robj), 0x10); +} + + /* packet type functions */ /* @@ -260,8 +343,13 @@ static int phonet_rcv(struct sk_buff *skb, struct net_device *dev, goto out; /* currently, we cannot be device 0 */ sk = pn_find_sock_by_sa(&sa); - if (sk == NULL) + if (sk == NULL) { + if (can_respond(skb)) { + send_obj_unreachable(skb); + send_reset_indications(skb); + } goto out; + } /* Push data to the socket (or other sockets connected to it). */ return sk_receive_skb(sk, skb, 0); |