// SPDX-License-Identifier: GPL-2.0 /* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ #include "vmlinux.h" #include <string.h> #include <bpf/bpf_helpers.h> #include <bpf/bpf_core_read.h> #include "bpf_kfuncs.h" __u8 SERVUN_REWRITE_ADDRESS[] = "\0bpf_cgroup_unix_test_rewrite"; SEC("cgroup/sendmsg_unix") int sendmsg_unix_prog(struct bpf_sock_addr *ctx) { struct bpf_sock_addr_kern *sa_kern = bpf_cast_to_kern_ctx(ctx); struct sockaddr_un *sa_kern_unaddr; __u32 unaddrlen = offsetof(struct sockaddr_un, sun_path) + sizeof(SERVUN_REWRITE_ADDRESS) - 1; int ret; /* Rewrite destination. */ ret = bpf_sock_addr_set_sun_path(sa_kern, SERVUN_REWRITE_ADDRESS, sizeof(SERVUN_REWRITE_ADDRESS) - 1); if (ret) return 0; if (sa_kern->uaddrlen != unaddrlen) return 0; sa_kern_unaddr = bpf_rdonly_cast(sa_kern->uaddr, bpf_core_type_id_kernel(struct sockaddr_un)); if (memcmp(sa_kern_unaddr->sun_path, SERVUN_REWRITE_ADDRESS, sizeof(SERVUN_REWRITE_ADDRESS) - 1) != 0) return 0; return 1; } char _license[] SEC("license") = "GPL";