From f2a6ee924d26527dc55a745dc917a820f34e64e5 Mon Sep 17 00:00:00 2001 From: Prankur Gupta Date: Tue, 17 Aug 2021 15:42:21 -0700 Subject: selftests/bpf: Add tests for {set|get} socket option from setsockopt BPF Adding selftests for the newly added functionality to call bpf_setsockopt() and bpf_getsockopt() from setsockopt BPF programs. Test Details: 1. BPF Program Checks for changes in IPV6_TCLASS(SOL_IPV6) via setsockopt If the cca for the socket is not cubic do nothing If the newly set value for IPV6_TCLASS is 45 (0x2d) (as per our use-case) then change the cc from cubic to reno 2. User Space Program Creates an AF_INET6 socket and set the cca for that to be "cubic" Attach the program and set the IPV6_TCLASS to 0x2d using setsockopt Verify the cca for the socket changed to reno Signed-off-by: Prankur Gupta Signed-off-by: Daniel Borkmann Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20210817224221.3257826-3-prankgup@fb.com --- .../selftests/bpf/progs/sockopt_qos_to_cc.c | 39 ++++++++++++++++++++++ 1 file changed, 39 insertions(+) create mode 100644 tools/testing/selftests/bpf/progs/sockopt_qos_to_cc.c (limited to 'tools/testing/selftests/bpf/progs/sockopt_qos_to_cc.c') diff --git a/tools/testing/selftests/bpf/progs/sockopt_qos_to_cc.c b/tools/testing/selftests/bpf/progs/sockopt_qos_to_cc.c new file mode 100644 index 000000000000..1bce83b6e3a7 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/sockopt_qos_to_cc.c @@ -0,0 +1,39 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2021 Facebook */ +#include +#include +#include +#include +#include +#include "bpf_tcp_helpers.h" + +char _license[] SEC("license") = "GPL"; + +SEC("cgroup/setsockopt") +int sockopt_qos_to_cc(struct bpf_sockopt *ctx) +{ + void *optval_end = ctx->optval_end; + int *optval = ctx->optval; + char buf[TCP_CA_NAME_MAX]; + char cc_reno[TCP_CA_NAME_MAX] = "reno"; + char cc_cubic[TCP_CA_NAME_MAX] = "cubic"; + + if (ctx->level != SOL_IPV6 || ctx->optname != IPV6_TCLASS) + return 1; + + if (optval + 1 > optval_end) + return 0; /* EPERM, bounds check */ + + if (bpf_getsockopt(ctx->sk, SOL_TCP, TCP_CONGESTION, &buf, sizeof(buf))) + return 0; + + if (!tcp_cc_eq(buf, cc_cubic)) + return 0; + + if (*optval == 0x2d) { + if (bpf_setsockopt(ctx->sk, SOL_TCP, TCP_CONGESTION, &cc_reno, + sizeof(cc_reno))) + return 0; + } + return 1; +} -- cgit v1.2.3