- dev - passt

[PATCH v8 00/27] Unified flow table
by David Gibson 20 Jul '24

20 Jul '24

This is the seventh draft of an implementation of more general "connection" tracking, as described at: https://pad.passt.top/p/NewForwardingModel This series changes the TCP connection table and hash table into a more general flow table that can track other protocols as well. Each flow uniformly keeps track of all the relevant addresses and ports, which will allow for more robust control of NAT and port forwarding. ICMP and UDP are converted to use the new flow table. This is based on the recent series of UDP flow table preliminaries. Caveats: * We roughly double the size of a connection/flow entry * We don't yet record the local address of flows initiated from a socket, even in cases where it's bound to a specific address. Changes since v7: * Rebase * Fix unintended regression in forwarding logic (we weren't applying map_gw logic to DNS packets, if they didn't hit explicit DNS forwarding rules). * Remove return value from pif_sockaddr(), in turned out not to be very useful. * More robust discarding of datagrams received between bind() and connect() on UDP reply sockets. * Avoid the name 'fside' for variables which was confusing in some contexts * Assorted minor changes based on feedback. Changes since v6: * Complete redesign of the UDP flow handling * Rebased (handling the change to bind() probing for local addresses was surprisingly fiddly) * Replace sockaddr_from_inany() with pif_sockaddr() which can correctly handle scope_id for different interfaces, and returns whether the address is non-trivial for convenience * Preserve specific loopback addresses in forwarding logic Changes since v5: * flowside_from_af() is now static * Small fixes to state verification * Pass protocol specific types into deferred/timer callbacks * No longer require complete forwarding address info for the hash table (we won't have it for UDP) * Fix bugs with logging of flow addresses * Make sure to initialise sin_zero field sockaddr_from_inany * Added patch better typing parameters to flow type specific callbacks * Terminology change "forwarded side" to "target side" * Assorted wording and style tweaks based on Stefano's review * Fold introduction of struct flowside and populating the initiating side together * Manage outbound addresses via the flow table as well * Support for UDP * Correct type of 'b' in flowside_lookup() (was a signed int) Changes since v4: * flowside_from_af() no longer fills in unspecified addresses when passed NULL * Split and rename flow hash lookup function * Clarified flow state transitions, and enforced where practical * Made side 0 always the initiating side of a flow, rather than letting the protocol specific code decide * Separated pifs from flowside addresses to allow better structure packing Changes since v3: * Complex rebase on top of the many things that have happened upstream since v2. * Assorted other changes. * Replace TAPFSIDE() and SOCKFSIDE() macros with local variables. Changes since v2: * Cosmetic fixes based on review * Extra doc comments for enum flow_type * Rename flowside to flowaddrs which turns out to make more sense in light of future changes * Fix bug where the socket flowaddrs for tap initiated connections wasn't initialised to match the socket address we were using in the case of map-gw NAT * New flowaddrs_from_sock() helper used in most cases which is cleaner and should avoid bugs like the above * Using newer centralised workarounds for clang-tidy issue 58992 * Remove duplicate definition of FLOW_MAX as maximum flow type and maximum number of tracked flows * Rebased on newer versions of preliminary work (ICMP, flow based dispatch and allocation, bind/address cleanups) * Unified hash table as well as base flow table * Integrated ICMP Changes since v1: * Terminology changes - "Endpoint" address/port instead of "correspondent" address/port - "flowside" instead of "demiflow" * Actually move the connection table to a new flow table structure in new files * Significant rearrangement of earlier patchs on top of that new table, to reduce churn David Gibson (27): flow: Common address information for initiating side flow: Common address information for target side tcp, flow: Remove redundant information, repack connection structures tcp: Obtain guest address from flowside tcp: Manage outbound address via flow table tcp: Simplify endpoint validation using flowside information tcp_splice: Eliminate SPLICE_V6 flag tcp, flow: Replace TCP specific hash function with general flow hash flow, tcp: Generalise TCP hash table to general flow hash table tcp: Re-use flow hash for initial sequence number generation icmp: Remove redundant id field from flow table entry icmp: Obtain destination addresses from the flowsides icmp: Look up ping flows using flow hash icmp: Eliminate icmp_id_map flow: Helper to create sockets based on flowside icmp: Manage outbound socket address via flow table flow, tcp: Flow based NAT and port forwarding for TCP flow, icmp: Use general flow forwarding rules for ICMP fwd: Update flow forwarding logic for UDP udp: Create flows for datagrams from originating sockets udp: Handle "spliced" datagrams with per-flow sockets udp: Remove obsolete splice tracking udp: Find or create flows for datagrams from tap interface udp: Direct datagrams from host to guest via flow table udp: Remove obsolete socket tracking udp: Remove rdelta port forwarding maps udp: Rename UDP listening sockets Makefile | 4 +- conf.c | 14 +- epoll_type.h | 6 +- flow.c | 483 +++++++++++++++++++++- flow.h | 47 +++ flow_table.h | 45 +- fwd.c | 187 ++++++++- fwd.h | 9 + icmp.c | 105 ++--- icmp_flow.h | 2 - inany.h | 2 - passt.c | 10 +- passt.h | 5 +- pif.c | 40 ++ pif.h | 17 + tap.c | 11 - tap.h | 1 - tcp.c | 522 ++++++----------------- tcp_buf.c | 6 +- tcp_conn.h | 47 +-- tcp_internal.h | 10 +- tcp_splice.c | 98 +---- tcp_splice.h | 5 +- udp.c | 1079 ++++++++++++++++++++---------------------------- udp.h | 35 +- udp_flow.h | 27 ++ util.c | 9 +- util.h | 3 + 28 files changed, 1563 insertions(+), 1266 deletions(-) create mode 100644 udp_flow.h -- 2.45.2

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[PATCH 0/4] RFC: Proof-of-concept based exeter+Avocado tests
by David Gibson 19 Jul '24

19 Jul '24

Here's a rough proof of concept showing how we could run tests for passt with Avocado and the exeter library I recently created. It includes Cleber's patch adding some basic Avocado tests and builds on that. The current draft is pretty janky: * The build rules to download and install the necessary pieces are messy * We create the Avocado job files from the exeter sources in the Makefile. Ideally Avocado would eventually be extended to handle this itself * We have more ugly make rules to mangle the right venv path into the exeter based python script * The names that Avocado sees for each test are terrible (nondescriptive and duplicated). This is the point I made in an earlier reply to Cleber's patch - we need some way of setting the test name from the job files. * There's some hacks to make sure things are executed from the right working directory But, it's a starting point. Stefano, I'm hoping most of the jank in the setup can be cleaned up. The bit I really want your opinion on is how the test scripts themslves look: test/build/static_checkers.exeter (shell) and test/build/build.exeter.in (Python). Cleber, I hope this concrete example makes it a bit clearer how I'm thinking about running tests from Avocado, without making the test themselves inherently tied to Avocado. Cleber Rosa (1): test: run static checkers with Avocado and JSON definitions David Gibson (3): test: Extend make targets to run Avocado tests test: Exeter based static tests test: Add exeter+Avocado based build tests test/.gitignore | 2 + test/Makefile | 33 +++++++++++- test/avocado/static_checkers.json | 16 ++++++ test/build/.gitignore | 2 + test/build/build.exeter.in | 89 +++++++++++++++++++++++++++++++ test/build/static_checkers.exeter | 17 ++++++ test/run_avocado | 49 +++++++++++++++++ 7 files changed, 207 insertions(+), 1 deletion(-) create mode 100644 test/avocado/static_checkers.json create mode 100644 test/build/.gitignore create mode 100644 test/build/build.exeter.in create mode 100755 test/build/static_checkers.exeter create mode 100755 test/run_avocado -- 2.45.2

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[PATCH 0/6] Of course there are more flow table preliminaries
by David Gibson 17 Jul '24

17 Jul '24

This series has some further preliminaries for the flow table. Specifically this is focused on some clean ups to handling of indicies for flows and sides. We also add some additional test programs for platform requirements. This is based on the series adding UDP error handling. David Gibson (6): flow, icmp, tcp: Clean up helpers for getting flow from index flow, tcp_splice: Prefer 'sidei' for variables referring to side index flow: Introduce flow_foreach_sidei() macro tcp_splice: Use parameterised macros for per-side event/flag bits doc: Test behaviour of closing duplicate UDP sockets doc: Extend zero-recv test with methods using msghdr doc/platform-requirements/.gitignore | 1 + doc/platform-requirements/Makefile | 4 +- doc/platform-requirements/recv-zero.c | 60 +++++++-- doc/platform-requirements/udp-close-dup.c | 105 +++++++++++++++ flow.h | 16 +-- flow_table.h | 48 +++++-- icmp.c | 22 +++- tcp.c | 28 +++- tcp_conn.h | 15 +-- tcp_splice.c | 152 ++++++++++++---------- 10 files changed, 332 insertions(+), 119 deletions(-) create mode 100644 doc/platform-requirements/udp-close-dup.c -- 2.45.2

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[PATCH v2 0/5] Handle error events on UDP sockets
by David Gibson 17 Jul '24

17 Jul '24

Add handling of the error queue for UDP sockets. We certainly need this for the flow table: this is the cause of the epoll loop that Stefano noticed. Even without the flow table it should improve robustness and debugability. Along the way we make a few other clean ups. Changes from v1: * Assorted minor changes based on Stefano's review David Gibson (5): conf: Don't configure port forwarding for a disabled protocol udp: Make udp_sock_recv static udp, tcp: Tweak handling of no_udp and no_tcp flags util: Add AF_UNSPEC support to sockaddr_ntop() udp: Handle errors on UDP sockets conf.c | 5 ++++ tcp.c | 14 ++++++++--- udp.c | 77 +++++++++++++++++++++++++++++++++++++++++++++++++++++++--- util.c | 33 +++++++++++++++++++++++++ util.h | 3 +++ 5 files changed, 125 insertions(+), 7 deletions(-) -- 2.45.2

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[PATCH v7 00/27] Unified flow table
by David Gibson 17 Jul '24

17 Jul '24

This is the seventh draft of an implementation of more general "connection" tracking, as described at: https://pad.passt.top/p/NewForwardingModel This series changes the TCP connection table and hash table into a more general flow table that can track other protocols as well. Each flow uniformly keeps track of all the relevant addresses and ports, which will allow for more robust control of NAT and port forwarding. ICMP and UDP are converted to use the new flow table. This is based on the recent series of UDP flow table preliminaries. Caveats: * We roughly double the size of a connection/flow entry * We don't yet record the local address of flows initiated from a socket, even in cases where it's bound to a specific address. Changes since v6: * Complete redesign of the UDP flow handling * Rebased (handling the change to bind() probing for local addresses was surprisingly fiddly) * Replace sockaddr_from_inany() with pif_sockaddr() which can correctly handle scope_id for different interfaces, and returns whether the address is non-trivial for convenience * Preserve specific loopback addresses in forwarding logic Changes since v5: * flowside_from_af() is now static * Small fixes to state verification * Pass protocol specific types into deferred/timer callbacks * No longer require complete forwarding address info for the hash table (we won't have it for UDP) * Fix bugs with logging of flow addresses * Make sure to initialise sin_zero field sockaddr_from_inany * Added patch better typing parameters to flow type specific callbacks * Terminology change "forwarded side" to "target side" * Assorted wording and style tweaks based on Stefano's review * Fold introduction of struct flowside and populating the initiating side together * Manage outbound addresses via the flow table as well * Support for UDP * Correct type of 'b' in flowside_lookup() (was a signed int) Changes since v4: * flowside_from_af() no longer fills in unspecified addresses when passed NULL * Split and rename flow hash lookup function * Clarified flow state transitions, and enforced where practical * Made side 0 always the initiating side of a flow, rather than letting the protocol specific code decide * Separated pifs from flowside addresses to allow better structure packing Changes since v3: * Complex rebase on top of the many things that have happened upstream since v2. * Assorted other changes. * Replace TAPFSIDE() and SOCKFSIDE() macros with local variables. Changes since v2: * Cosmetic fixes based on review * Extra doc comments for enum flow_type * Rename flowside to flowaddrs which turns out to make more sense in light of future changes * Fix bug where the socket flowaddrs for tap initiated connections wasn't initialised to match the socket address we were using in the case of map-gw NAT * New flowaddrs_from_sock() helper used in most cases which is cleaner and should avoid bugs like the above * Using newer centralised workarounds for clang-tidy issue 58992 * Remove duplicate definition of FLOW_MAX as maximum flow type and maximum number of tracked flows * Rebased on newer versions of preliminary work (ICMP, flow based dispatch and allocation, bind/address cleanups) * Unified hash table as well as base flow table * Integrated ICMP Changes since v1: * Terminology changes - "Endpoint" address/port instead of "correspondent" address/port - "flowside" instead of "demiflow" * Actually move the connection table to a new flow table structure in new files * Significant rearrangement of earlier patchs on top of that new table, to reduce churn David Gibson (27): flow: Common address information for initiating side flow: Common address information for target side tcp, flow: Remove redundant information, repack connection structures tcp: Obtain guest address from flowside tcp: Manage outbound address via flow table tcp: Simplify endpoint validation using flowside information tcp_splice: Eliminate SPLICE_V6 flag tcp, flow: Replace TCP specific hash function with general flow hash flow, tcp: Generalise TCP hash table to general flow hash table tcp: Re-use flow hash for initial sequence number generation icmp: Remove redundant id field from flow table entry icmp: Obtain destination addresses from the flowsides icmp: Look up ping flows using flow hash icmp: Eliminate icmp_id_map flow: Helper to create sockets based on flowside icmp: Manage outbound socket address via flow table flow, tcp: Flow based NAT and port forwarding for TCP flow, icmp: Use general flow forwarding rules for ICMP fwd: Update flow forwarding logic for UDP udp: Create flows for datagrams from originating sockets udp: Handle "spliced" datagrams with per-flow sockets udp: Remove obsolete splice tracking udp: Find or create flows for datagrams from tap interface udp: Direct datagrams from host to guest via flow table udp: Remove obsolete socket tracking udp: Remove rdelta port forwarding maps udp: Rename UDP listening sockets Makefile | 4 +- conf.c | 14 +- epoll_type.h | 6 +- flow.c | 481 +++++++++++++++++++++- flow.h | 47 +++ flow_table.h | 57 ++- fwd.c | 184 ++++++++- fwd.h | 9 + icmp.c | 105 ++--- icmp_flow.h | 2 - inany.h | 2 - passt.c | 10 +- passt.h | 5 +- pif.c | 45 +++ pif.h | 17 + tap.c | 11 - tap.h | 1 - tcp.c | 521 ++++++------------------ tcp_buf.c | 6 +- tcp_conn.h | 51 +-- tcp_internal.h | 10 +- tcp_splice.c | 98 +---- tcp_splice.h | 5 +- udp.c | 1055 +++++++++++++++++++----------------------------- udp.h | 33 +- udp_flow.h | 27 ++ util.c | 9 +- util.h | 3 + 28 files changed, 1549 insertions(+), 1269 deletions(-) create mode 100644 udp_flow.h -- 2.45.2

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[PATCH 0/5] Handle error events on UDP sockets
by David Gibson 17 Jul '24

17 Jul '24

Add handling of the error queue for UDP sockets. We certainly need this for the flow table: this is the cause of the epoll loop that Stefano noticed. Even without the flow table it should improve robustness and debugability. Along the way we make a few other clean ups. David Gibson (5): conf: Don't configure port forwarding for a disabled protocol udp: Make udp_sock_recv static udp, tcp: Tweak handling of no_udp and no_tcp flags util: Add AF_UNSPEC support to sockaddr_ntop() udp: Handle errors on UDP sockets conf.c | 5 ++++ tcp.c | 14 ++++++++--- udp.c | 76 ++++++++++++++++++++++++++++++++++++++++++++++++++++++---- util.c | 33 +++++++++++++++++++++++++ util.h | 3 +++ 5 files changed, 124 insertions(+), 7 deletions(-) -- 2.45.2

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[PATCH v9 0/2] Add support for SO_PEEK_OFF
by Jon Maloy 15 Jul '24

15 Jul '24

We add support for the SO_PEEK_OFF option, plus work around a kernel bug discovered along the way. Jon Maloy (2): tcp: leverage support of SO_PEEK_OFF socket option when available tcp: handle shrunk window advertisemenst from guest tcp.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++++++++--- tcp.h | 3 +++ tcp_buf.c | 25 ++++++++++++++++------ 3 files changed, 81 insertions(+), 9 deletions(-) -- 2.45.2

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[PATCH] doc: Trivial fix for reuseaddr-priority
by David Gibson 15 Jul '24

15 Jul '24

This test program checks for particular behaviour regardless of order of operations. So, we step through the test with all possible orders for a number of different of parts. Or at least, we're supposed to, a copy pasta error led to using the same order for two things which should be independent. Fixes: 299c40750 ("doc: Add program to document and test assumptions...") Reported-by: David Taylor <davidt(a)yadt.co.uk> Signed-off-by: David Gibson <david(a)gibson.dropbear.id.au> --- doc/platform-requirements/reuseaddr-priority.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/doc/platform-requirements/reuseaddr-priority.c b/doc/platform-requirements/reuseaddr-priority.c index 644553f8..701b6fff 100644 --- a/doc/platform-requirements/reuseaddr-priority.c +++ b/doc/platform-requirements/reuseaddr-priority.c @@ -222,7 +222,7 @@ static void check_all_orders(void) for (k = 0; k < norders; k++) for (l = 0; l < norders; l++) check_one_order(orders[i], orders[j], - orders[j], orders[l]); + orders[k], orders[l]); } int main(int argc, char *argv[]) -- 2.45.2

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[PATCH/RFC] test: run static checkers with Avocado and JSON definitions
by Cleber Rosa 15 Jul '24

15 Jul '24

This adds a script and configuration to use the Avocado Testing Framework to run, at this time, the static checkers. The actual tests are defined using (JSON based) files, that are known to Avocado as "recipes". The JSON files are parsed and "resolved" into tests by Avocado's "runnables-recipe" resolver. The syntax allows for any kind of test supported by Avocado to be defined there, including a mix of different test types. By the nature of Avocado's default configuration, those will run in parallel in the host system. For more complex tests or different use cases, Avocado could help in future versions by running those in different environments such as containers. The entry point ("test/run_avocado") is intended to be an optional tool at this point, coexisting with the current implementation to run tests. It uses Avocado's Job API to create a job with, at this point, the static checkers suite. The installation of Avocado itself is left to users, given that the details on how to install it (virtual environments and specific tooling) can be a very different and long discussion. Signed-off-by: Cleber Rosa <crosa(a)redhat.com> --- test/avocado/static_checkers.json | 16 ++++++++++ test/run_avocado | 49 +++++++++++++++++++++++++++++++ 2 files changed, 65 insertions(+) create mode 100644 test/avocado/static_checkers.json create mode 100755 test/run_avocado diff --git a/test/avocado/static_checkers.json b/test/avocado/static_checkers.json new file mode 100644 index 0000000..5fae43e --- /dev/null +++ b/test/avocado/static_checkers.json @@ -0,0 +1,16 @@ +[ + { + "kind": "exec-test", + "uri": "make", + "args": [ + "clang-tidy" + ] + }, + { + "kind": "exec-test", + "uri": "make", + "args": [ + "cppcheck" + ] + } +] diff --git a/test/run_avocado b/test/run_avocado new file mode 100755 index 0000000..37db17c --- /dev/null +++ b/test/run_avocado @@ -0,0 +1,49 @@ +#!/usr/bin/env python3 + +import os +import sys + + +def check_avocado_version(): + minimum_version = 106.0 + + def error_out(): + print( + f"Avocado version {minimum_version} or later is required.\n" + f"You may install it with: \n" + f" python3 -m pip install avocado-framework", + file=sys.stderr, + ) + sys.exit(1) + + try: + from avocado import VERSION + + if (float(VERSION)) < minimum_version: + error_out() + except ImportError: + error_out() + + +check_avocado_version() +from avocado.core.job import Job +from avocado.core.suite import TestSuite + + +def main(): + repo_root_path = os.path.abspath( + os.path.dirname(os.path.dirname(os.path.dirname(__file__))) + ) + config = { + "resolver.references": [ + os.path.join(repo_root_path, "test", "avocado", "static_checkers.json") + ], + "runner.identifier_format": "{args[0]}", + } + suite = TestSuite.from_config(config, name="static_checkers") + with Job(config, [suite]) as j: + return j.run() + + +if __name__ == "__main__": + sys.exit(main()) -- 2.45.2

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[PATCH v2 00/11] Preliminaries for UDP flow support
by David Gibson 15 Jul '24

15 Jul '24

The redesign of UDP flows required (or at least, suggested) a new batch of prelininary changes that don't rely on the core of the flow table rework. Changes since v1: * Assorted minor fixes based on Stefano's feedback * Moved test programs from contrib/ to doc/ David Gibson (11): util: sock_l4() determine protocol from epoll type rather than the reverse flow: Add flow_sidx_valid() helper udp: Pass full epoll reference through more of sock handler path udp: Rename IOV and mmsghdr arrays udp: Unify udp[46]_mh_splice udp: Unify udp[46]_l2_iov udp: Don't repeatedly initialise udp[46]_eth_hdr udp: Move some more of sock_handler tasks into sub-functions udp: Consolidate datagram batching doc: Add program to document and test assumptions about SO_REUSEADDR doc: Test behaviour of zero length datagram recv()s doc/platform-requirements/.gitignore | 2 + doc/platform-requirements/Makefile | 45 +++ doc/platform-requirements/README | 18 + doc/platform-requirements/common.c | 66 ++++ doc/platform-requirements/common.h | 47 +++ doc/platform-requirements/recv-zero.c | 74 ++++ .../reuseaddr-priority.c | 240 ++++++++++++ epoll_type.h | 41 ++ flow.h | 11 + flow_table.h | 2 +- icmp.c | 2 +- passt.h | 32 -- tcp.c | 17 +- udp.c | 365 +++++++++--------- util.c | 48 +-- util.h | 3 +- 16 files changed, 756 insertions(+), 257 deletions(-) create mode 100644 doc/platform-requirements/.gitignore create mode 100644 doc/platform-requirements/Makefile create mode 100644 doc/platform-requirements/README create mode 100644 doc/platform-requirements/common.c create mode 100644 doc/platform-requirements/common.h create mode 100644 doc/platform-requirements/recv-zero.c create mode 100644 doc/platform-requirements/reuseaddr-priority.c create mode 100644 epoll_type.h -- 2.45.2

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