From 0b05b2a49e430220876f8faa7e4778dc7497033c Mon Sep 17 00:00:00 2001
From: Patrick McHardy <kaber@trash.net>
Date: Tue, 5 Jul 2005 14:10:21 -0700
Subject: [NET]: Consolidate common code in net/core/filter.c
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/core/filter.c | 90 ++++++++++++++++++++-----------------------------------
1 file changed, 33 insertions(+), 57 deletions(-)
(limited to 'net')
diff --git a/net/core/filter.c b/net/core/filter.c
index e1267b465d..3923428a84 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -36,7 +36,7 @@
#include <linux/filter.h>
/* No hurry in this branch */
-static u8 *load_pointer(struct sk_buff *skb, int k)
+static void *__load_pointer(struct sk_buff *skb, int k)
{
u8 *ptr = NULL;
@@ -50,6 +50,18 @@ static u8 *load_pointer(struct sk_buff *skb, int k)
return NULL;
}
+static inline void *load_pointer(struct sk_buff *skb, int k,
+ unsigned int size, void *buffer)
+{
+ if (k >= 0)
+ return skb_header_pointer(skb, k, size, buffer);
+ else {
+ if (k >= SKF_AD_OFF)
+ return NULL;
+ return __load_pointer(skb, k);
+ }
+}
+
/**
* sk_run_filter - run a filter on a socket
* @skb: buffer to run the filter on
@@ -64,15 +76,16 @@ static u8 *load_pointer(struct sk_buff *skb, int k)
int sk_run_filter(struct sk_buff *skb, struct sock_filter *filter, int flen)
{
- unsigned char *data = skb->data;
/* len is UNSIGNED. Byte wide insns relies only on implicit
type casts to prevent reading arbitrary memory locations.
*/
unsigned int len = skb->len-skb->data_len;
struct sock_filter *fentry; /* We walk down these */
+ void *ptr;
u32 A = 0; /* Accumulator */
u32 X = 0; /* Index Register */
u32 mem[BPF_MEMWORDS]; /* Scratch Memory Store */
+ u32 tmp;
int k;
int pc;
@@ -168,67 +181,28 @@ int sk_run_filter(struct sk_buff *skb, struct sock_filter *filter, int flen)
case BPF_LD|BPF_W|BPF_ABS:
k = fentry->k;
load_w:
- if (k < 0) {
- u8 *ptr;
-
- if (k >= SKF_AD_OFF)
- break;
- ptr = load_pointer(skb, k);
- if (ptr) {
- A = ntohl(*(u32*)ptr);
- continue;
- }
- } else {
- u32 _tmp, *p;
- p = skb_header_pointer(skb, k, 4, &_tmp);
- if (p != NULL) {
- A = ntohl(*p);
- continue;
- }
+ ptr = load_pointer(skb, k, 4, &tmp);
+ if (ptr != NULL) {
+ A = ntohl(*(u32 *)ptr);
+ continue;
}
return 0;
case BPF_LD|BPF_H|BPF_ABS:
k = fentry->k;
load_h:
- if (k < 0) {
- u8 *ptr;
-
- if (k >= SKF_AD_OFF)
- break;
- ptr = load_pointer(skb, k);
- if (ptr) {
- A = ntohs(*(u16*)ptr);
- continue;
- }
- } else {
- u16 _tmp, *p;
- p = skb_header_pointer(skb, k, 2, &_tmp);
- if (p != NULL) {
- A = ntohs(*p);
- continue;
- }
+ ptr = load_pointer(skb, k, 2, &tmp);
+ if (ptr != NULL) {
+ A = ntohs(*(u16 *)ptr);
+ continue;
}
return 0;
case BPF_LD|BPF_B|BPF_ABS:
k = fentry->k;
load_b:
- if (k < 0) {
- u8 *ptr;
-
- if (k >= SKF_AD_OFF)
- break;
- ptr = load_pointer(skb, k);
- if (ptr) {
- A = *ptr;
- continue;
- }
- } else {
- u8 _tmp, *p;
- p = skb_header_pointer(skb, k, 1, &_tmp);
- if (p != NULL) {
- A = *p;
- continue;
- }
+ ptr = load_pointer(skb, k, 1, &tmp);
+ if (ptr != NULL) {
+ A = *(u8 *)ptr;
+ continue;
}
return 0;
case BPF_LD|BPF_W|BPF_LEN:
@@ -247,10 +221,12 @@ load_b:
k = X + fentry->k;
goto load_b;
case BPF_LDX|BPF_B|BPF_MSH:
- if (fentry->k >= len)
- return 0;
- X = (data[fentry->k] & 0xf) << 2;
- continue;
+ ptr = load_pointer(skb, fentry->k, 1, &tmp);
+ if (ptr != NULL) {
+ X = (*(u8 *)ptr & 0xf) << 2;
+ continue;
+ }
+ return 0;
case BPF_LD|BPF_IMM:
A = fentry->k;
continue;
--
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