49 lines
883 B
C
49 lines
883 B
C
// SPDX-License-Identifier: GPL-2.0
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#include "vmlinux.h"
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#include <bpf/bpf_helpers.h>
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int xdpf_sz;
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int sinfo_sz;
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int data_len;
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int pull_len;
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#define XDP_PACKET_HEADROOM 256
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SEC("xdp.frags")
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int xdp_find_sizes(struct xdp_md *ctx)
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{
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xdpf_sz = sizeof(struct xdp_frame);
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sinfo_sz = __PAGE_SIZE - XDP_PACKET_HEADROOM -
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(ctx->data_end - ctx->data);
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return XDP_PASS;
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}
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SEC("xdp.frags")
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int xdp_pull_data_prog(struct xdp_md *ctx)
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{
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__u8 *data_end = (void *)(long)ctx->data_end;
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__u8 *data = (void *)(long)ctx->data;
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__u8 *val_p;
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int err;
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if (data_len != data_end - data)
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return XDP_DROP;
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err = bpf_xdp_pull_data(ctx, pull_len);
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if (err)
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return XDP_DROP;
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val_p = (void *)(long)ctx->data + 1024;
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if (val_p + 1 > (void *)(long)ctx->data_end)
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return XDP_DROP;
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if (*val_p != 0xbb)
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return XDP_DROP;
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return XDP_PASS;
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}
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char _license[] SEC("license") = "GPL";
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