twx-linux/include/linux/filter.h
Eric Dumazet 164954454a filter: do not output bpf image address for security reason
Do not leak starting address of BPF JIT code for non root users,
as it might help intruders to perform an attack.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-19 23:56:41 -07:00

147 lines
3.3 KiB
C

/*
* Linux Socket Filter Data Structures
*/
#ifndef __LINUX_FILTER_H__
#define __LINUX_FILTER_H__
#include <linux/atomic.h>
#include <linux/compat.h>
#include <uapi/linux/filter.h>
#ifdef CONFIG_COMPAT
/*
* A struct sock_filter is architecture independent.
*/
struct compat_sock_fprog {
u16 len;
compat_uptr_t filter; /* struct sock_filter * */
};
#endif
struct sk_buff;
struct sock;
struct sk_filter
{
atomic_t refcnt;
unsigned int len; /* Number of filter blocks */
unsigned int (*bpf_func)(const struct sk_buff *skb,
const struct sock_filter *filter);
struct rcu_head rcu;
struct sock_filter insns[0];
};
static inline unsigned int sk_filter_len(const struct sk_filter *fp)
{
return fp->len * sizeof(struct sock_filter) + sizeof(*fp);
}
extern int sk_filter(struct sock *sk, struct sk_buff *skb);
extern unsigned int sk_run_filter(const struct sk_buff *skb,
const struct sock_filter *filter);
extern int sk_unattached_filter_create(struct sk_filter **pfp,
struct sock_fprog *fprog);
extern void sk_unattached_filter_destroy(struct sk_filter *fp);
extern int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
extern int sk_detach_filter(struct sock *sk);
extern int sk_chk_filter(struct sock_filter *filter, unsigned int flen);
extern int sk_get_filter(struct sock *sk, struct sock_filter __user *filter, unsigned len);
#ifdef CONFIG_BPF_JIT
#include <stdarg.h>
#include <linux/linkage.h>
#include <linux/printk.h>
extern void bpf_jit_compile(struct sk_filter *fp);
extern void bpf_jit_free(struct sk_filter *fp);
static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen,
u32 pass, void *image)
{
pr_err("flen=%u proglen=%u pass=%u image=%pK\n",
flen, proglen, pass, image);
if (image)
print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET,
16, 1, image, proglen, false);
}
#define SK_RUN_FILTER(FILTER, SKB) (*FILTER->bpf_func)(SKB, FILTER->insns)
#else
static inline void bpf_jit_compile(struct sk_filter *fp)
{
}
static inline void bpf_jit_free(struct sk_filter *fp)
{
}
#define SK_RUN_FILTER(FILTER, SKB) sk_run_filter(SKB, FILTER->insns)
#endif
enum {
BPF_S_RET_K = 1,
BPF_S_RET_A,
BPF_S_ALU_ADD_K,
BPF_S_ALU_ADD_X,
BPF_S_ALU_SUB_K,
BPF_S_ALU_SUB_X,
BPF_S_ALU_MUL_K,
BPF_S_ALU_MUL_X,
BPF_S_ALU_DIV_X,
BPF_S_ALU_MOD_K,
BPF_S_ALU_MOD_X,
BPF_S_ALU_AND_K,
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,
BPF_S_ALU_RSH_X,
BPF_S_ALU_NEG,
BPF_S_LD_W_ABS,
BPF_S_LD_H_ABS,
BPF_S_LD_B_ABS,
BPF_S_LD_W_LEN,
BPF_S_LD_W_IND,
BPF_S_LD_H_IND,
BPF_S_LD_B_IND,
BPF_S_LD_IMM,
BPF_S_LDX_W_LEN,
BPF_S_LDX_B_MSH,
BPF_S_LDX_IMM,
BPF_S_MISC_TAX,
BPF_S_MISC_TXA,
BPF_S_ALU_DIV_K,
BPF_S_LD_MEM,
BPF_S_LDX_MEM,
BPF_S_ST,
BPF_S_STX,
BPF_S_JMP_JA,
BPF_S_JMP_JEQ_K,
BPF_S_JMP_JEQ_X,
BPF_S_JMP_JGE_K,
BPF_S_JMP_JGE_X,
BPF_S_JMP_JGT_K,
BPF_S_JMP_JGT_X,
BPF_S_JMP_JSET_K,
BPF_S_JMP_JSET_X,
/* Ancillary data */
BPF_S_ANC_PROTOCOL,
BPF_S_ANC_PKTTYPE,
BPF_S_ANC_IFINDEX,
BPF_S_ANC_NLATTR,
BPF_S_ANC_NLATTR_NEST,
BPF_S_ANC_MARK,
BPF_S_ANC_QUEUE,
BPF_S_ANC_HATYPE,
BPF_S_ANC_RXHASH,
BPF_S_ANC_CPU,
BPF_S_ANC_ALU_XOR_X,
BPF_S_ANC_SECCOMP_LD_W,
BPF_S_ANC_VLAN_TAG,
BPF_S_ANC_VLAN_TAG_PRESENT,
BPF_S_ANC_PAY_OFFSET,
};
#endif /* __LINUX_FILTER_H__ */