Quelle  verifier_lwt.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0
/* Converted from tools/testing/selftests/bpf/verifier/lwt.c */

#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include "bpf_misc.h"

SEC("lwt_in")
__description("invalid direct packet write for LWT_IN")
__failure __msg("cannot write into packet")
__naked void packet_write_for_lwt_in(void)
{
 asm volatile (" \
 r2 = *(u32*)(r1 + %[__sk_buff_data]);  \
 r3 = *(u32*)(r1 + %[__sk_buff_data_end]); \
 r0 = r2;     \
 r0 += 8;     \
 if r0 > r3 goto l0_%=;    \
 *(u8*)(r2 + 0) = r2;    \
l0_%=: r0 = 0;      \
 exit;      \
" :
 : __imm_const(__sk_buff_data, offsetof(struct __sk_buff, data)),
   __imm_const(__sk_buff_data_end, offsetof(struct __sk_buff, data_end))
 : __clobber_all);
}

SEC("lwt_out")
__description("invalid direct packet write for LWT_OUT")
__failure __msg("cannot write into packet")
__naked void packet_write_for_lwt_out(void)
{
 asm volatile (" \
 r2 = *(u32*)(r1 + %[__sk_buff_data]);  \
 r3 = *(u32*)(r1 + %[__sk_buff_data_end]); \
 r0 = r2;     \
 r0 += 8;     \
 if r0 > r3 goto l0_%=;    \
 *(u8*)(r2 + 0) = r2;    \
l0_%=: r0 = 0;      \
 exit;      \
" :
 : __imm_const(__sk_buff_data, offsetof(struct __sk_buff, data)),
   __imm_const(__sk_buff_data_end, offsetof(struct __sk_buff, data_end))
 : __clobber_all);
}

SEC("lwt_xmit")
__description("direct packet write for LWT_XMIT")
__success __retval(0)
__naked void packet_write_for_lwt_xmit(void)
{
 asm volatile (" \
 r2 = *(u32*)(r1 + %[__sk_buff_data]);  \
 r3 = *(u32*)(r1 + %[__sk_buff_data_end]); \
 r0 = r2;     \
 r0 += 8;     \
 if r0 > r3 goto l0_%=;    \
 *(u8*)(r2 + 0) = r2;    \
l0_%=: r0 = 0;      \
 exit;      \
" :
 : __imm_const(__sk_buff_data, offsetof(struct __sk_buff, data)),
   __imm_const(__sk_buff_data_end, offsetof(struct __sk_buff, data_end))
 : __clobber_all);
}

SEC("lwt_in")
__description("direct packet read for LWT_IN")
__success __retval(0)
__naked void packet_read_for_lwt_in(void)
{
 asm volatile (" \
 r2 = *(u32*)(r1 + %[__sk_buff_data]);  \
 r3 = *(u32*)(r1 + %[__sk_buff_data_end]); \
 r0 = r2;     \
 r0 += 8;     \
 if r0 > r3 goto l0_%=;    \
 r0 = *(u8*)(r2 + 0);    \
l0_%=: r0 = 0;      \
 exit;      \
" :
 : __imm_const(__sk_buff_data, offsetof(struct __sk_buff, data)),
   __imm_const(__sk_buff_data_end, offsetof(struct __sk_buff, data_end))
 : __clobber_all);
}

SEC("lwt_out")
__description("direct packet read for LWT_OUT")
__success __retval(0)
__naked void packet_read_for_lwt_out(void)
{
 asm volatile (" \
 r2 = *(u32*)(r1 + %[__sk_buff_data]);  \
 r3 = *(u32*)(r1 + %[__sk_buff_data_end]); \
 r0 = r2;     \
 r0 += 8;     \
 if r0 > r3 goto l0_%=;    \
 r0 = *(u8*)(r2 + 0);    \
l0_%=: r0 = 0;      \
 exit;      \
" :
 : __imm_const(__sk_buff_data, offsetof(struct __sk_buff, data)),
   __imm_const(__sk_buff_data_end, offsetof(struct __sk_buff, data_end))
 : __clobber_all);
}

SEC("lwt_xmit")
__description("direct packet read for LWT_XMIT")
__success __retval(0)
__naked void packet_read_for_lwt_xmit(void)
{
 asm volatile (" \
 r2 = *(u32*)(r1 + %[__sk_buff_data]);  \
 r3 = *(u32*)(r1 + %[__sk_buff_data_end]); \
 r0 = r2;     \
 r0 += 8;     \
 if r0 > r3 goto l0_%=;    \
 r0 = *(u8*)(r2 + 0);    \
l0_%=: r0 = 0;      \
 exit;      \
" :
 : __imm_const(__sk_buff_data, offsetof(struct __sk_buff, data)),
   __imm_const(__sk_buff_data_end, offsetof(struct __sk_buff, data_end))
 : __clobber_all);
}

SEC("lwt_xmit")
__description("overlapping checks for direct packet access")
__success __retval(0)
__naked void checks_for_direct_packet_access(void)
{
 asm volatile (" \
 r2 = *(u32*)(r1 + %[__sk_buff_data]);  \
 r3 = *(u32*)(r1 + %[__sk_buff_data_end]); \
 r0 = r2;     \
 r0 += 8;     \
 if r0 > r3 goto l0_%=;    \
 r1 = r2;     \
 r1 += 6;     \
 if r1 > r3 goto l0_%=;    \
 r0 = *(u16*)(r2 + 6);    \
l0_%=: r0 = 0;      \
 exit;      \
" :
 : __imm_const(__sk_buff_data, offsetof(struct __sk_buff, data)),
   __imm_const(__sk_buff_data_end, offsetof(struct __sk_buff, data_end))
 : __clobber_all);
}

SEC("lwt_xmit")
__description("make headroom for LWT_XMIT")
__success __retval(0)
__naked void make_headroom_for_lwt_xmit(void)
{
 asm volatile (" \
 r6 = r1;     \
 r2 = 34;     \
 r3 = 0;      \
 call %[bpf_skb_change_head];   \
 /* split for s390 to succeed */ \
 r1 = r6;     \
 r2 = 42;     \
 r3 = 0;      \
 call %[bpf_skb_change_head];   \
 r0 = 0;      \
 exit;      \
" :
 : __imm(bpf_skb_change_head)
 : __clobber_all);
}

SEC("socket")
__description("invalid access of tc_classid for LWT_IN")
__failure __msg("invalid bpf_context access")
__failure_unpriv
__naked void tc_classid_for_lwt_in(void)
{
 asm volatile (" \
 r0 = *(u32*)(r1 + %[__sk_buff_tc_classid]); \
 exit;      \
" :
 : __imm_const(__sk_buff_tc_classid, offsetof(struct __sk_buff, tc_classid))
 : __clobber_all);
}

SEC("socket")
__description("invalid access of tc_classid for LWT_OUT")
__failure __msg("invalid bpf_context access")
__failure_unpriv
__naked void tc_classid_for_lwt_out(void)
{
 asm volatile (" \
 r0 = *(u32*)(r1 + %[__sk_buff_tc_classid]); \
 exit;      \
" :
 : __imm_const(__sk_buff_tc_classid, offsetof(struct __sk_buff, tc_classid))
 : __clobber_all);
}

SEC("socket")
__description("invalid access of tc_classid for LWT_XMIT")
__failure __msg("invalid bpf_context access")
__failure_unpriv
__naked void tc_classid_for_lwt_xmit(void)
{
 asm volatile (" \
 r0 = *(u32*)(r1 + %[__sk_buff_tc_classid]); \
 exit;      \
" :
 : __imm_const(__sk_buff_tc_classid, offsetof(struct __sk_buff, tc_classid))
 : __clobber_all);
}

SEC("lwt_in")
__description("check skb->tc_classid half load not permitted for lwt prog")
__failure __msg("invalid bpf_context access")
__naked void not_permitted_for_lwt_prog(void)
{
 asm volatile (
 "r0 = 0;"
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 "r0 = *(u16*)(r1 + %[__sk_buff_tc_classid]);"
#else
 "r0 = *(u16*)(r1 + %[__imm_0]);"
#endif
 "exit;"
 :
 : __imm_const(__imm_0, offsetof(struct __sk_buff, tc_classid) + 2),
   __imm_const(__sk_buff_tc_classid, offsetof(struct __sk_buff, tc_classid))
 : __clobber_all);
}

char _license[] SEC("license") = "GPL";