Quelle  wide_access.c   Sprache: C

#define BPF_SOCK_ADDR_STORE(field, off, res, err, flgs) \
{ \
 "wide store to bpf_sock_addr." #field "[" #off "]", \
 .insns = { \
 BPF_MOV64_IMM(BPF_REG_0, 1), \
 BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, \
      offsetof(struct bpf_sock_addr, field[off])), \
 BPF_EXIT_INSN(), \
 }, \
 .result = res, \
 .prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR, \
 .expected_attach_type = BPF_CGROUP_UDP6_SENDMSG, \
 .errstr = err, \
 .flags = flgs, \
}

/* user_ip6[0] is u64 aligned */
BPF_SOCK_ADDR_STORE(user_ip6, 0, ACCEPT,
      NULL, 0),
BPF_SOCK_ADDR_STORE(user_ip6, 1, REJECT,
      "invalid bpf_context access off=12 size=8",
      F_NEEDS_EFFICIENT_UNALIGNED_ACCESS),
BPF_SOCK_ADDR_STORE(user_ip6, 2, ACCEPT,
      NULL, 0),
BPF_SOCK_ADDR_STORE(user_ip6, 3, REJECT,
      "invalid bpf_context access off=20 size=8",
      F_NEEDS_EFFICIENT_UNALIGNED_ACCESS),

/* msg_src_ip6[0] is _not_ u64 aligned */
BPF_SOCK_ADDR_STORE(msg_src_ip6, 0, REJECT,
      "invalid bpf_context access off=44 size=8",
      F_NEEDS_EFFICIENT_UNALIGNED_ACCESS),
BPF_SOCK_ADDR_STORE(msg_src_ip6, 1, ACCEPT,
      NULL, 0),
BPF_SOCK_ADDR_STORE(msg_src_ip6, 2, REJECT,
      "invalid bpf_context access off=52 size=8",
      F_NEEDS_EFFICIENT_UNALIGNED_ACCESS),
BPF_SOCK_ADDR_STORE(msg_src_ip6, 3, REJECT,
      "invalid bpf_context access off=56 size=8", 0),

#undef BPF_SOCK_ADDR_STORE

#define BPF_SOCK_ADDR_LOAD(field, off, res, err, flgs) \
{ \
 "wide load from bpf_sock_addr." #field "[" #off "]", \
 .insns = { \
 BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, \
      offsetof(struct bpf_sock_addr, field[off])), \
 BPF_MOV64_IMM(BPF_REG_0, 1), \
 BPF_EXIT_INSN(), \
 }, \
 .result = res, \
 .prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR, \
 .expected_attach_type = BPF_CGROUP_UDP6_SENDMSG, \
 .errstr = err, \
 .flags = flgs, \
}

/* user_ip6[0] is u64 aligned */
BPF_SOCK_ADDR_LOAD(user_ip6, 0, ACCEPT,
     NULL, 0),
BPF_SOCK_ADDR_LOAD(user_ip6, 1, REJECT,
     "invalid bpf_context access off=12 size=8",
      F_NEEDS_EFFICIENT_UNALIGNED_ACCESS),
BPF_SOCK_ADDR_LOAD(user_ip6, 2, ACCEPT,
     NULL, 0),
BPF_SOCK_ADDR_LOAD(user_ip6, 3, REJECT,
     "invalid bpf_context access off=20 size=8",
      F_NEEDS_EFFICIENT_UNALIGNED_ACCESS),

/* msg_src_ip6[0] is _not_ u64 aligned */
BPF_SOCK_ADDR_LOAD(msg_src_ip6, 0, REJECT,
     "invalid bpf_context access off=44 size=8",
      F_NEEDS_EFFICIENT_UNALIGNED_ACCESS),
BPF_SOCK_ADDR_LOAD(msg_src_ip6, 1, ACCEPT,
     NULL, 0),
BPF_SOCK_ADDR_LOAD(msg_src_ip6, 2, REJECT,
     "invalid bpf_context access off=52 size=8",
      F_NEEDS_EFFICIENT_UNALIGNED_ACCESS),
BPF_SOCK_ADDR_LOAD(msg_src_ip6, 3, REJECT,
     "invalid bpf_context access off=56 size=8", 0),

#undef BPF_SOCK_ADDR_LOAD