eBPF

Jan 1, 0001

Definition

eBPF (extended Berkeley Packet Filter) is a technology that allows the execution of sandboxed programs in the Linux kernel without changing kernel source code or loading kernel modules. It is used for a variety of purposes, including network performance monitoring, security enforcement, and tracing. eBPF programs are verified for safety before execution, ensuring they do not compromise kernel stability.

Secure Settings Example

// eBPF program to monitor network packets securely
SEC("socket")
int bpf_prog(struct __sk_buff *skb) {
    // Ensure the program only reads packet headers
    if (bpf_skb_load_bytes(skb, 0, &hdr, sizeof(hdr)) < 0)
        return 0;
    // Additional logic for packet inspection
    return 0;
}

Insecure Settings Example

// eBPF program with potential security risks
SEC("socket")
int bpf_prog(struct __sk_buff *skb) {
    // Directly accessing packet data without bounds checking
    char *data = (char *)(long)skb->data;
    // Unsafe operations on packet data
    if (data[0] == 'A') {
        // Potentially unsafe logic
    }
    return 0;
}