diff options
author | Daniel Borkmann <dborkman@redhat.com> | 2013-03-19 16:36:10 +0100 |
---|---|---|
committer | Daniel Borkmann <dborkman@redhat.com> | 2013-03-19 16:36:10 +0100 |
commit | ceae98914962e4375a98db2622b65ecf44b0232a (patch) | |
tree | 1560778e9ea194247c1cec6d827dde882a860b58 /bpf_parser.y | |
parent | e4c98bb91e35dba56a077e8e5b9c70556fdd4e24 (diff) |
bpfc: filter: add poff ancillary operation
In preparation for [1], add the #poff operation, so that users can
dynamically truncate packets on the payload start offset. This is
useful for several reasons: privacy, speed, ...
Example for bpfc:
ld #poff
ret a
[1] http://thread.gmane.org/gmane.linux.network/262512
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Diffstat (limited to 'bpf_parser.y')
-rw-r--r-- | bpf_parser.y | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/bpf_parser.y b/bpf_parser.y index 7f6bcc8..459ea99 100644 --- a/bpf_parser.y +++ b/bpf_parser.y @@ -132,7 +132,7 @@ static int find_intr_offset_or_panic(char *label_to_search) %token OP_LDXI %token K_PKT_LEN K_PROTO K_TYPE K_NLATTR K_NLATTR_NEST K_MARK K_QUEUE K_HATYPE -%token K_RXHASH K_CPU K_IFIDX K_VLANT K_VLANP +%token K_RXHASH K_CPU K_IFIDX K_VLANT K_VLANP K_POFF %token ':' ',' '[' ']' '(' ')' 'x' 'a' '+' 'M' '*' '&' '#' @@ -235,6 +235,9 @@ ldb | OP_LDB K_VLANP { set_curr_instr(BPF_LD | BPF_B | BPF_ABS, 0, 0, SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT); } + | OP_LDB K_POFF { + set_curr_instr(BPF_LD | BPF_B | BPF_ABS, 0, 0, + SKF_AD_OFF + SKF_AD_PAY_OFFSET); } ; ldh @@ -278,6 +281,9 @@ ldh | OP_LDH K_VLANP { set_curr_instr(BPF_LD | BPF_H | BPF_ABS, 0, 0, SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT); } + | OP_LDH K_POFF { + set_curr_instr(BPF_LD | BPF_H | BPF_ABS, 0, 0, + SKF_AD_OFF + SKF_AD_PAY_OFFSET); } ; ldi @@ -326,6 +332,9 @@ ld | OP_LD K_VLANP { set_curr_instr(BPF_LD | BPF_W | BPF_ABS, 0, 0, SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT); } + | OP_LD K_POFF { + set_curr_instr(BPF_LD | BPF_W | BPF_ABS, 0, 0, + SKF_AD_OFF + SKF_AD_PAY_OFFSET); } | OP_LD 'M' '[' number ']' { set_curr_instr(BPF_LD | BPF_MEM, 0, 0, $4); } | OP_LD '[' 'x' '+' number ']' { |