From 855ddb56d81fcdc76ab60b80062359ea09a1515d Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sat, 27 Oct 2012 02:26:22 +0000 Subject: [PATCH] x86: bpf_jit_comp: add vlan tag support This patch is a follow-up for patch "net: filter: add vlan tag access" to support the new VLAN_TAG/VLAN_TAG_PRESENT accessors in BPF JIT. Signed-off-by: Eric Dumazet Cc: Ani Sinha Cc: Daniel Borkmann Signed-off-by: David S. Miller --- arch/x86/net/bpf_jit_comp.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index 520d2bd0b9c5..d11a47099d33 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -11,6 +11,7 @@ #include #include #include +#include /* * Conventions : @@ -212,6 +213,8 @@ void bpf_jit_compile(struct sk_filter *fp) case BPF_S_ANC_MARK: case BPF_S_ANC_RXHASH: case BPF_S_ANC_CPU: + case BPF_S_ANC_VLAN_TAG: + case BPF_S_ANC_VLAN_TAG_PRESENT: case BPF_S_ANC_QUEUE: case BPF_S_LD_W_ABS: case BPF_S_LD_H_ABS: @@ -515,6 +518,24 @@ void bpf_jit_compile(struct sk_filter *fp) CLEAR_A(); #endif break; + case BPF_S_ANC_VLAN_TAG: + case BPF_S_ANC_VLAN_TAG_PRESENT: + BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_tci) != 2); + if (is_imm8(offsetof(struct sk_buff, vlan_tci))) { + /* movzwl off8(%rdi),%eax */ + EMIT4(0x0f, 0xb7, 0x47, offsetof(struct sk_buff, vlan_tci)); + } else { + EMIT3(0x0f, 0xb7, 0x87); /* movzwl off32(%rdi),%eax */ + EMIT(offsetof(struct sk_buff, vlan_tci), 4); + } + BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000); + if (filter[i].code == BPF_S_ANC_VLAN_TAG) { + EMIT3(0x80, 0xe4, 0xef); /* and $0xef,%ah */ + } else { + EMIT3(0xc1, 0xe8, 0x0c); /* shr $0xc,%eax */ + EMIT3(0x83, 0xe0, 0x01); /* and $0x1,%eax */ + } + break; case BPF_S_LD_W_ABS: func = CHOOSE_LOAD_FUNC(K, sk_load_word); common_load: seen |= SEEN_DATAREF; -- 2.30.2