46 lines
840 B
C
46 lines
840 B
C
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// SPDX-License-Identifier: GPL-2.0
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#include <linux/stddef.h>
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#include <linux/bpf.h>
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <bpf/bpf_helpers.h>
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#include <bpf/bpf_endian.h>
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static __always_inline int bind_prog(struct bpf_sock_addr *ctx, int family)
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{
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struct bpf_sock *sk;
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sk = ctx->sk;
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if (!sk)
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return 0;
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if (sk->family != family)
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return 0;
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if (ctx->type != SOCK_STREAM)
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return 0;
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/* Return 1 OR'ed with the first bit set to indicate
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* that CAP_NET_BIND_SERVICE should be bypassed.
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*/
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if (ctx->user_port == bpf_htons(111))
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return (1 | 2);
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return 1;
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}
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SEC("cgroup/bind4")
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int bind_v4_prog(struct bpf_sock_addr *ctx)
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{
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return bind_prog(ctx, AF_INET);
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}
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SEC("cgroup/bind6")
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int bind_v6_prog(struct bpf_sock_addr *ctx)
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{
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return bind_prog(ctx, AF_INET6);
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}
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char _license[] SEC("license") = "GPL";
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