lib: Add np1_flow_read and np1_flow_write calls

Reading/writing to (N + 1)-flows from the IPCP was using a raw QoS flow
to bypass some functions in the ipcp_flow_read call. But this call was
broken for keepalive packets.  Fixing the ipcp_flow_read call for
(N - 1) flows causes the IPCPs to drop 0-byte keepalive packets coming from
(N + 1) client flows.

>From now on, there is a dedicated call for (N + 1) reads/writes from
the IPCPs that's more efficient and cleaner. The (N + 1) flow internal
QoS is now also defaulted to a qos_np1 qosspec, instead of tampering
with the qosspec requested by the (N + 1) client.

Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>

1 files changed, 15 insertions, 5 deletions

diff --git a/src/ipcpd/udp/main.c b/src/ipcpd/udp/main.c
index d3104163..6e32638d 100644
--- a/src/ipcpd/udp/main.c
+++ b/src/ipcpd/udp/main.c
@@ -450,9 +450,11 @@ static void * ipcp_udp_packet_reader(void * o)
         eid_p = (uint32_t *) buf;
 
         while (true) {
-                struct mgmt_frame * frame;
-                struct sockaddr_in  r_saddr;
-                socklen_t           len;
+                struct mgmt_frame *  frame;
+                struct sockaddr_in   r_saddr;
+                socklen_t            len;
+                struct shm_du_buff * sdb;
+                uint8_t *            head;
 
                 len = sizeof(r_saddr);
 
@@ -493,7 +495,15 @@ static void * ipcp_udp_packet_reader(void * o)
                         continue;
                 }
 
-                flow_write(eid, data, n - sizeof(eid));
+                n-= sizeof(eid);
+
+                if (ipcp_sdb_reserve(&sdb, n))
+                        continue;
+
+                head = shm_du_buff_head(sdb);
+                memcpy(head, data, n);
+                if (np1_flow_write(eid, sdb) < 0)
+                        ipcp_sdb_release(sdb);
         }
 
         return 0;
@@ -536,7 +546,7 @@ static void * ipcp_udp_packet_writer(void * o)
                         if (fqueue_type(fq) != FLOW_PKT)
                                 continue;
 
-                        if (ipcp_flow_read(fd, &sdb)) {
+                        if (np1_flow_read(fd, &sdb)) {
                                 log_dbg("Bad read from fd %d.", fd);
                                 continue;
                         }