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[NET]: Consolidate common code in net/core/filter.c

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Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Patrick McHardy 2005-07-05 14:10:21 -07:00 committed by David S. Miller
parent 6935d46c2d
commit 0b05b2a49e
1 changed files with 33 additions and 57 deletions
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82
net/core/filter.c
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@ -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;
@ -168,68 +181,29 @@ 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);
ptr = load_pointer(skb, k, 4, &tmp);
if (ptr != NULL) {
A = ntohl(*(u32 *)ptr);
continue;
}
} else {
u32 _tmp, *p;
p = skb_header_pointer(skb, k, 4, &_tmp);
if (p != NULL) {
A = ntohl(*p);
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);
ptr = load_pointer(skb, k, 2, &tmp);
if (ptr != NULL) {
A = ntohs(*(u16 *)ptr);
continue;
}
} else {
u16 _tmp, *p;
p = skb_header_pointer(skb, k, 2, &_tmp);
if (p != NULL) {
A = ntohs(*p);
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;
ptr = load_pointer(skb, k, 1, &tmp);
if (ptr != NULL) {
A = *(u8 *)ptr;
continue;
}
} else {
u8 _tmp, *p;
p = skb_header_pointer(skb, k, 1, &_tmp);
if (p != NULL) {
A = *p;
continue;
}
}
return 0;
case BPF_LD|BPF_W|BPF_LEN:
A = 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;
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;