diff options
Diffstat (limited to 'net/hsr/hsr_framereg.c')
| -rw-r--r-- | net/hsr/hsr_framereg.c | 99 |
1 files changed, 96 insertions, 3 deletions
diff --git a/net/hsr/hsr_framereg.c b/net/hsr/hsr_framereg.c index 73bc6f659812..4ce471a2f387 100644 --- a/net/hsr/hsr_framereg.c +++ b/net/hsr/hsr_framereg.c @@ -35,6 +35,7 @@ static bool seq_nr_after(u16 a, u16 b) #define seq_nr_before(a, b) seq_nr_after((b), (a)) #define seq_nr_before_or_eq(a, b) (!seq_nr_after((a), (b))) +#define PRP_DROP_WINDOW_LEN 32768 bool hsr_addr_is_redbox(struct hsr_priv *hsr, unsigned char *addr) { @@ -176,8 +177,11 @@ static struct hsr_node *hsr_add_node(struct hsr_priv *hsr, new_node->time_in[i] = now; new_node->time_out[i] = now; } - for (i = 0; i < HSR_PT_PORTS; i++) + for (i = 0; i < HSR_PT_PORTS; i++) { new_node->seq_out[i] = seq_out; + new_node->seq_expected[i] = seq_out + 1; + new_node->seq_start[i] = seq_out + 1; + } if (san && hsr->proto_ops->handle_san_frame) hsr->proto_ops->handle_san_frame(san, rx_port, new_node); @@ -482,9 +486,11 @@ void hsr_register_frame_in(struct hsr_node *node, struct hsr_port *port, * 0 otherwise, or * negative error code on error */ -int hsr_register_frame_out(struct hsr_port *port, struct hsr_node *node, - u16 sequence_nr) +int hsr_register_frame_out(struct hsr_port *port, struct hsr_frame_info *frame) { + struct hsr_node *node = frame->node_src; + u16 sequence_nr = frame->sequence_nr; + spin_lock_bh(&node->seq_out_lock); if (seq_nr_before_or_eq(sequence_nr, node->seq_out[port->type]) && time_is_after_jiffies(node->time_out[port->type] + @@ -499,6 +505,93 @@ int hsr_register_frame_out(struct hsr_port *port, struct hsr_node *node, return 0; } +/* Adaptation of the PRP duplicate discard algorithm described in wireshark + * wiki (https://wiki.wireshark.org/PRP) + * + * A drop window is maintained for both LANs with start sequence set to the + * first sequence accepted on the LAN that has not been seen on the other LAN, + * and expected sequence set to the latest received sequence number plus one. + * + * When a frame is received on either LAN it is compared against the received + * frames on the other LAN. If it is outside the drop window of the other LAN + * the frame is accepted and the drop window is updated. + * The drop window for the other LAN is reset. + * + * 'port' is the outgoing interface + * 'frame' is the frame to be sent + * + * Return: + * 1 if frame can be shown to have been sent recently on this interface, + * 0 otherwise + */ +int prp_register_frame_out(struct hsr_port *port, struct hsr_frame_info *frame) +{ + enum hsr_port_type other_port; + enum hsr_port_type rcv_port; + struct hsr_node *node; + u16 sequence_diff; + u16 sequence_exp; + u16 sequence_nr; + + /* out-going frames are always in order + * and can be checked the same way as for HSR + */ + if (frame->port_rcv->type == HSR_PT_MASTER) + return hsr_register_frame_out(port, frame); + + /* for PRP we should only forward frames from the slave ports + * to the master port + */ + if (port->type != HSR_PT_MASTER) + return 1; + + node = frame->node_src; + sequence_nr = frame->sequence_nr; + sequence_exp = sequence_nr + 1; + rcv_port = frame->port_rcv->type; + other_port = rcv_port == HSR_PT_SLAVE_A ? HSR_PT_SLAVE_B : + HSR_PT_SLAVE_A; + + spin_lock_bh(&node->seq_out_lock); + if (time_is_before_jiffies(node->time_out[port->type] + + msecs_to_jiffies(HSR_ENTRY_FORGET_TIME)) || + (node->seq_start[rcv_port] == node->seq_expected[rcv_port] && + node->seq_start[other_port] == node->seq_expected[other_port])) { + /* the node hasn't been sending for a while + * or both drop windows are empty, forward the frame + */ + node->seq_start[rcv_port] = sequence_nr; + } else if (seq_nr_before(sequence_nr, node->seq_expected[other_port]) && + seq_nr_before_or_eq(node->seq_start[other_port], sequence_nr)) { + /* drop the frame, update the drop window for the other port + * and reset our drop window + */ + node->seq_start[other_port] = sequence_exp; + node->seq_expected[rcv_port] = sequence_exp; + node->seq_start[rcv_port] = node->seq_expected[rcv_port]; + spin_unlock_bh(&node->seq_out_lock); + return 1; + } + + /* update the drop window for the port where this frame was received + * and clear the drop window for the other port + */ + node->seq_start[other_port] = node->seq_expected[other_port]; + node->seq_expected[rcv_port] = sequence_exp; + sequence_diff = sequence_exp - node->seq_start[rcv_port]; + if (sequence_diff > PRP_DROP_WINDOW_LEN) + node->seq_start[rcv_port] = sequence_exp - PRP_DROP_WINDOW_LEN; + + node->time_out[port->type] = jiffies; + node->seq_out[port->type] = sequence_nr; + spin_unlock_bh(&node->seq_out_lock); + return 0; +} + +#if IS_MODULE(CONFIG_PRP_DUP_DISCARD_KUNIT_TEST) +EXPORT_SYMBOL(prp_register_frame_out); +#endif + static struct hsr_port *get_late_port(struct hsr_priv *hsr, struct hsr_node *node) { |