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* ipcpd: Use 64-bit flow endpoint IDs for DTDimitri Staessens2020-12-071-33/+87
| | | | | | | | | | | | | 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 <[email protected]> Signed-off-by: Sander Vrijders <[email protected]>
* ipcpd: Remove DT-FA bypass on receiver sideDimitri Staessens2020-12-071-11/+65
| | | | | | | | | | | | | | | | | | | | | | | | | | The DT will now post all packets for N+1 flows through the flow allocator component. This means that N+1 flows can be monitored through the flow allocator stats, and N-1 flows through the DT stats. The DT component still keeps stats for the local components (FA and DHT), but this can be removed once the DHT has its own RIB output. The flow allocator show statistics for Sent packets: total packets that were presented for sending on this specific flow Send failed: packets that were unable to be sent Received packets: total packets that were presented by the DT component on this specific flow Received failed: packets that were unable to be delivered These stats are presented as both packet counts and byte counts. To know how many were successful, the values for failed need to be subtracted from the values for total. Signed-off-by: Dimitri Staessens <[email protected]> Signed-off-by: Sander Vrijders <[email protected]>
* ipcpd: Add RIB statistics for flow allocatorDimitri Staessens2020-12-051-7/+188
| | | | | | | | | | The RIB will now show some stats for the flow allocator, including congestion avoidance statistics. This is needed before decoupling the data transfer component and the flow allocator as some current stats show in DT will move to FA. Signed-off-by: Dimitri Staessens <[email protected]> Signed-off-by: Sander Vrijders <[email protected]>
* ipcpd: Don't update for deallocated flowsDimitri Staessens2020-12-021-0/+5
| | | | | | | | | | | The dt component bypasses the flow allocator on the receiver side, and may try to update congestion context when the flow has already been deallocated by the receiver. I will fix this bypass and always pass through the flow allocator sometime soon; for now, I added a check in the flow allocator call to avoid the SEGV. Signed-off-by: Dimitri Staessens <[email protected]> Signed-off-by: Sander Vrijders <[email protected]>
* ipcpd: Add congestion avoidance policiesDimitri Staessens2020-12-021-52/+170
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <[email protected]> Signed-off-by: Sander Vrijders <[email protected]>
* ipcpd: Fix condition variable in flow allocatorDimitri Staessens2020-10-111-2/+13
| | | | | | | | The condition variable was not initialized correctly and using the wrong clock for pthread_cond_timedwait. Signed-off-by: Dimitri Staessens <[email protected]> Signed-off-by: Sander Vrijders <[email protected]>
* lib, ipcpd: piggyback ECDHE on flow allocationDimitri Staessens2020-02-251-23/+37
| | | | | | | | | | | The initial implementation for the ECDHE key exchange was doing the key exchange after a flow was established. The public keys are now sent allowg on the flow allocation messages, so that an encrypted tunnel can be created within 1 RTT. The flow allocation steps had to be extended to pass the opaque data ('piggybacking'). Signed-off-by: Dimitri Staessens <[email protected]> Signed-off-by: Sander Vrijders <[email protected]>
* build: Update copyright to 20200.16.0Dimitri Staessens2020-01-021-1/+1
| | | | | Signed-off-by: Dimitri Staessens <[email protected]> Signed-off-by: Sander Vrijders <[email protected]>
* lib: Add per-message encryption with OpenSSLDimitri Staessens2019-08-031-0/+3
| | | | | | | | | | | | | | | | | | | This adds a per-message symmetric encryption using the OpenSSL library. At flow allocation, an Elliptic Curve Diffie-Hellman exchange is performed to derive a shared secret, which is then hashed using SHA3-256 to be used as a key for symmetric AES-256 encryption. Each message on an encrypted flow adds a small crypto header that includes a random 128-bit Initialization Vector (IV). If the server does not have OpenSSL enabled, the flow allocation will fail with an -ECRYPT error. Future optimizations are to piggyback the public keys on the flow allocation message, and to enable per-flow encryption that maintains the context of the encryption over multiple packets and doesn't require sending IVs. Signed-off-by: Dimitri Staessens <[email protected]> Signed-off-by: Sander Vrijders <[email protected]>
* build: Refactor normal to unicastDimitri Staessens2019-07-291-0/+491
This completes the renaming of the normal IPCP to the unicast IPCP in the sources, to get everything consistent with the documentation. Signed-off-by: Dimitri Staessens <[email protected]> Signed-off-by: Sander Vrijders <[email protected]>