ouroboros/src/tools, branch 0.18.0

ipcpd: Single UDP port for the ipcpd-udp

2021-01-03T10:59:59+00:00

The UDP layer will now use a single (configurable) UDP port, default 3435. This makes it easer to allocate flows as a client from behind a NAT firewall without having to configure port forwarding rules. So basically, from now on Ouroboros traffic is transported over a bidirectional : UDP tunnel. The reason for not using/allowing different client/server ports is that it would require reading from different sockets using select() or something similar, but since we need the EID anyway (mgmt packets arrive on the same server UDP port), there's not a lot of benefit in doing it. Now the operation is similar to the ipcpd-eth, with the port somewhat functioning as a "layer name", where in UDP, the Ethertype functions as a "layer name". Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

build: Update email addresses

2021-01-03T10:57:05+00:00

The ugent email addresses are shut down, updated to Ouroboros mail addresses. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

build: Update copyright to 2021

2021-01-03T10:56:28+00:00

Happy New Year, Ouroboros! Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

ipcpd: Use 64-bit flow endpoint IDs for DT

2020-12-07T17:39:48+00:00

The EIDs are now 64-bit. This makes it a tad harder to guess them (think of port scanning). The implementation has only the most significant 32 bits random to quickly map EIDs to N+1 flows. While this is equivalent to a random cookie as a check on flows, the rationale is that valid endpoint IDs should be pretty hard to guess (and thus be 64-bit random at least). Ideally one would use content-addressable memory for this kind of mapping. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

ipcpd: Add congestion avoidance policies

2020-12-02T18:21:29+00:00

This adds congestion avoidance policies to the unicast IPCP. The default policy is a multi-bit explicit congestion avoidance algorithm based on data-center TCP congestion avoidance (DCTCP) to relay information about the maximum queue depth that packets experienced to the receiver. There's also a "nop" policy to disable congestion avoidance for testing and benchmarking purposes. The (initial) API for congestion avoidance policies is: void * (* ctx_create)(void); void (* ctx_destroy)(void * ctx); These calls create / and or destroy a context for congestion control for a specific flow. Thread-safety of the context is the responsability of the flow allocator (operations on the ctx should be performed under a lock). ca_wnd_t (* ctx_update_snd)(void * ctx, size_t len); This is the sender call to update the context, and should be called for every packet that is sent on the flow. The len parameter in this API is the packet length, which allows calculating the bandwidth. It returns an opaque union type that is used for the call to check/wait if the congestion window is open or closed (and allowing to release locks before waiting). bool (* ctx_update_rcv)(void * ctx, size_t len, uint8_t ecn, uint16_t * ece); This is the call to update the flow congestion context on the receiver side. It should be called for every received packet. It gets the ecn value from the packet and its length, and returns the ECE (explicit congestion experienced) value to be sent to the sender in case of congestion. The boolean returned signals whether or not a congestion update needs to be sent. void (* ctx_update_ece)(void * ctx, uint16_t ece); This is the call for the sending side top update the context when it receives an ECE update from the receiver. void (* wnd_wait)(ca_wnd_t wnd); This is a (blocking) call that waits for the congestion window to clear. It should be stateless (to avoid waiting under locks). This may change later on if passing the context is needed for different algorithms. uint8_t (* calc_ecn)(int fd, size_t len); This is the call that intermediate IPCPs(routers) should use to update the ECN field on passing packets. The multi-bit ECN policy bases the value for the ECN field on the depth of the rbuff queue packets will be sent on. I created another call to grab the queue depth as fccntl is write-locking the application. We can further optimize this to avoid most locking on the rbuff. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

tools: Default ocbr to sleep and add --spin option

2020-12-02T18:21:25+00:00

The ocbr client was spinning the CPU by default, which made sense on lab servers with dual xeons, but not so much for average users. Now sleeping becomes the default. Busy waiting can be enabled using --spin if needed. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

tools: Use read timeouts in ocbr server

2020-11-25T14:35:31+00:00

The ocbr server was using non-blocking reads (probably because we didn't have read timeouts when we wrote it) and was using a whole CPU core per thread. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

tools: Fix error handling in oping write thread

2020-10-11T12:10:18+00:00

The function was returning under a cleanup handler, which is not allowed. We don't do anything with the return value if the write thread ends, so just stopping the thread is fine. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

tools: Improve locking in oping server

2020-09-25T11:20:02+00:00

There was a dealloc() call in oping server under mutex, which could leave that mutex locked when the thread was cancelled, causing oping to hang on exit. This avoids calling dealloc under lock. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

ipcpd: Remove some unused variables

2020-05-02T09:52:54+00:00

The compiler spotted some variables that weren't really used. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders