net/bpf: split VLAN_PRESENT bit handling from VLAN_TCI

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Michał Mirosław 2018-11-10 19:58:35 +01:00 committed by David S. Miller
parent 5109f9fd6a
commit 9c21225597
1 changed files with 21 additions and 19 deletions

View File

@ -296,22 +296,21 @@ static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg,
break;
case SKF_AD_VLAN_TAG:
case SKF_AD_VLAN_TAG_PRESENT:
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_tci) != 2);
BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);
/* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */
*insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
offsetof(struct sk_buff, vlan_tci));
if (skb_field == SKF_AD_VLAN_TAG) {
*insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg,
~VLAN_TAG_PRESENT);
} else {
/* dst_reg >>= 12 */
*insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 12);
/* dst_reg &= 1 */
#ifdef VLAN_TAG_PRESENT
*insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, ~VLAN_TAG_PRESENT);
#endif
break;
case SKF_AD_VLAN_TAG_PRESENT:
*insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_VLAN_PRESENT_OFFSET());
if (PKT_VLAN_PRESENT_BIT)
*insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, PKT_VLAN_PRESENT_BIT);
if (PKT_VLAN_PRESENT_BIT < 7)
*insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 1);
}
break;
}
@ -6140,19 +6139,22 @@ static u32 bpf_convert_ctx_access(enum bpf_access_type type,
break;
case offsetof(struct __sk_buff, vlan_present):
case offsetof(struct __sk_buff, vlan_tci):
BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);
*target_size = 1;
*insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg,
PKT_VLAN_PRESENT_OFFSET());
if (PKT_VLAN_PRESENT_BIT)
*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, PKT_VLAN_PRESENT_BIT);
if (PKT_VLAN_PRESENT_BIT < 7)
*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 1);
break;
case offsetof(struct __sk_buff, vlan_tci):
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, vlan_tci, 2,
target_size));
if (si->off == offsetof(struct __sk_buff, vlan_tci)) {
*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg,
~VLAN_TAG_PRESENT);
} else {
*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 12);
*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 1);
}
#ifdef VLAN_TAG_PRESENT
*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, ~VLAN_TAG_PRESENT);
#endif
break;
case offsetof(struct __sk_buff, cb[0]) ...