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| author | Daniel Borkmann <dxchgb@gmail.com> | 2012-09-24 02:23:59 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-09-24 16:49:21 -0400 |
| commit | 9e49e88958feb41ec701fa34b44723dabadbc28c (patch) | |
| tree | ab17d7738505ade25a0a16bf442086cbf07d0f22 | |
| parent | 718cffc4ac65f01c6f1efd6baec8b4b5ff0c76b5 (diff) | |
| download | linux-9e49e88958feb41ec701fa34b44723dabadbc28c.tar.gz linux-9e49e88958feb41ec701fa34b44723dabadbc28c.tar.bz2 linux-9e49e88958feb41ec701fa34b44723dabadbc28c.zip | |
filter: add XOR instruction for use with X/K
SKF_AD_ALU_XOR_X has been added a while ago, but as an 'ancillary'
operation that is invoked through a negative offset in K within BPF
load operations. Since BPF_MOD has recently been added, BPF_XOR should
also be part of the common ALU operations. Removing SKF_AD_ALU_XOR_X
might not be an option since this is exposed to user space.
Signed-off-by: Daniel Borkmann <daniel.borkmann@tik.ee.ethz.ch>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/linux/filter.h | 3 | ||||
| -rw-r--r-- | net/core/filter.c | 12 |
2 files changed, 12 insertions, 3 deletions
diff --git a/include/linux/filter.h b/include/linux/filter.h index 3cf5fd561d86..2ded090e10f4 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -75,6 +75,7 @@ struct sock_fprog { /* Required for SO_ATTACH_FILTER. */ #define BPF_RSH 0x70 #define BPF_NEG 0x80 #define BPF_MOD 0x90 +#define BPF_XOR 0xa0 #define BPF_JA 0x00 #define BPF_JEQ 0x10 @@ -204,6 +205,8 @@ enum { BPF_S_ALU_AND_X, BPF_S_ALU_OR_K, BPF_S_ALU_OR_X, + BPF_S_ALU_XOR_K, + BPF_S_ALU_XOR_X, BPF_S_ALU_LSH_K, BPF_S_ALU_LSH_X, BPF_S_ALU_RSH_K, diff --git a/net/core/filter.c b/net/core/filter.c index fbe3a8d12570..3d92ebb7fbcf 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -187,6 +187,13 @@ unsigned int sk_run_filter(const struct sk_buff *skb, case BPF_S_ALU_OR_K: A |= K; continue; + case BPF_S_ANC_ALU_XOR_X: + case BPF_S_ALU_XOR_X: + A ^= X; + continue; + case BPF_S_ALU_XOR_K: + A ^= K; + continue; case BPF_S_ALU_LSH_X: A <<= X; continue; @@ -334,9 +341,6 @@ load_b: case BPF_S_ANC_CPU: A = raw_smp_processor_id(); continue; - case BPF_S_ANC_ALU_XOR_X: - A ^= X; - continue; case BPF_S_ANC_NLATTR: { struct nlattr *nla; @@ -483,6 +487,8 @@ int sk_chk_filter(struct sock_filter *filter, unsigned int flen) [BPF_ALU|BPF_AND|BPF_X] = BPF_S_ALU_AND_X, [BPF_ALU|BPF_OR|BPF_K] = BPF_S_ALU_OR_K, [BPF_ALU|BPF_OR|BPF_X] = BPF_S_ALU_OR_X, + [BPF_ALU|BPF_XOR|BPF_K] = BPF_S_ALU_XOR_K, + [BPF_ALU|BPF_XOR|BPF_X] = BPF_S_ALU_XOR_X, [BPF_ALU|BPF_LSH|BPF_K] = BPF_S_ALU_LSH_K, [BPF_ALU|BPF_LSH|BPF_X] = BPF_S_ALU_LSH_X, [BPF_ALU|BPF_RSH|BPF_K] = BPF_S_ALU_RSH_K, |