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-rw-r--r--arch/x86/net/bpf_jit_comp32.c2419
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diff --git a/arch/x86/net/bpf_jit_comp32.c b/arch/x86/net/bpf_jit_comp32.c
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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Just-In-Time compiler for eBPF filters on IA32 (32bit x86)
4 *
5 * Author: Wang YanQing (udknight@gmail.com)
6 * The code based on code and ideas from:
7 * Eric Dumazet (eric.dumazet@gmail.com)
8 * and from:
9 * Shubham Bansal <illusionist.neo@gmail.com>
10 */
11
12#include <linux/netdevice.h>
13#include <linux/filter.h>
14#include <linux/if_vlan.h>
15#include <asm/cacheflush.h>
16#include <asm/set_memory.h>
17#include <asm/nospec-branch.h>
18#include <linux/bpf.h>
19
20/*
21 * eBPF prog stack layout:
22 *
23 * high
24 * original ESP => +-----+
25 * | | callee saved registers
26 * +-----+
27 * | ... | eBPF JIT scratch space
28 * BPF_FP,IA32_EBP => +-----+
29 * | ... | eBPF prog stack
30 * +-----+
31 * |RSVD | JIT scratchpad
32 * current ESP => +-----+
33 * | |
34 * | ... | Function call stack
35 * | |
36 * +-----+
37 * low
38 *
39 * The callee saved registers:
40 *
41 * high
42 * original ESP => +------------------+ \
43 * | ebp | |
44 * current EBP => +------------------+ } callee saved registers
45 * | ebx,esi,edi | |
46 * +------------------+ /
47 * low
48 */
49
50static u8 *emit_code(u8 *ptr, u32 bytes, unsigned int len)
51{
52 if (len == 1)
53 *ptr = bytes;
54 else if (len == 2)
55 *(u16 *)ptr = bytes;
56 else {
57 *(u32 *)ptr = bytes;
58 barrier();
59 }
60 return ptr + len;
61}
62
63#define EMIT(bytes, len) \
64 do { prog = emit_code(prog, bytes, len); cnt += len; } while (0)
65
66#define EMIT1(b1) EMIT(b1, 1)
67#define EMIT2(b1, b2) EMIT((b1) + ((b2) << 8), 2)
68#define EMIT3(b1, b2, b3) EMIT((b1) + ((b2) << 8) + ((b3) << 16), 3)
69#define EMIT4(b1, b2, b3, b4) \
70 EMIT((b1) + ((b2) << 8) + ((b3) << 16) + ((b4) << 24), 4)
71
72#define EMIT1_off32(b1, off) \
73 do { EMIT1(b1); EMIT(off, 4); } while (0)
74#define EMIT2_off32(b1, b2, off) \
75 do { EMIT2(b1, b2); EMIT(off, 4); } while (0)
76#define EMIT3_off32(b1, b2, b3, off) \
77 do { EMIT3(b1, b2, b3); EMIT(off, 4); } while (0)
78#define EMIT4_off32(b1, b2, b3, b4, off) \
79 do { EMIT4(b1, b2, b3, b4); EMIT(off, 4); } while (0)
80
81#define jmp_label(label, jmp_insn_len) (label - cnt - jmp_insn_len)
82
83static bool is_imm8(int value)
84{
85 return value <= 127 && value >= -128;
86}
87
88static bool is_simm32(s64 value)
89{
90 return value == (s64) (s32) value;
91}
92
93#define STACK_OFFSET(k) (k)
94#define TCALL_CNT (MAX_BPF_JIT_REG + 0) /* Tail Call Count */
95
96#define IA32_EAX (0x0)
97#define IA32_EBX (0x3)
98#define IA32_ECX (0x1)
99#define IA32_EDX (0x2)
100#define IA32_ESI (0x6)
101#define IA32_EDI (0x7)
102#define IA32_EBP (0x5)
103#define IA32_ESP (0x4)
104
105/*
106 * List of x86 cond jumps opcodes (. + s8)
107 * Add 0x10 (and an extra 0x0f) to generate far jumps (. + s32)
108 */
109#define IA32_JB 0x72
110#define IA32_JAE 0x73
111#define IA32_JE 0x74
112#define IA32_JNE 0x75
113#define IA32_JBE 0x76
114#define IA32_JA 0x77
115#define IA32_JL 0x7C
116#define IA32_JGE 0x7D
117#define IA32_JLE 0x7E
118#define IA32_JG 0x7F
119
120/*
121 * Map eBPF registers to IA32 32bit registers or stack scratch space.
122 *
123 * 1. All the registers, R0-R10, are mapped to scratch space on stack.
124 * 2. We need two 64 bit temp registers to do complex operations on eBPF
125 * registers.
126 * 3. For performance reason, the BPF_REG_AX for blinding constant, is
127 * mapped to real hardware register pair, IA32_ESI and IA32_EDI.
128 *
129 * As the eBPF registers are all 64 bit registers and IA32 has only 32 bit
130 * registers, we have to map each eBPF registers with two IA32 32 bit regs
131 * or scratch memory space and we have to build eBPF 64 bit register from those.
132 *
133 * We use IA32_EAX, IA32_EDX, IA32_ECX, IA32_EBX as temporary registers.
134 */
135static const u8 bpf2ia32[][2] = {
136 /* Return value from in-kernel function, and exit value from eBPF */
137 [BPF_REG_0] = {STACK_OFFSET(0), STACK_OFFSET(4)},
138
139 /* The arguments from eBPF program to in-kernel function */
140 /* Stored on stack scratch space */
141 [BPF_REG_1] = {STACK_OFFSET(8), STACK_OFFSET(12)},
142 [BPF_REG_2] = {STACK_OFFSET(16), STACK_OFFSET(20)},
143 [BPF_REG_3] = {STACK_OFFSET(24), STACK_OFFSET(28)},
144 [BPF_REG_4] = {STACK_OFFSET(32), STACK_OFFSET(36)},
145 [BPF_REG_5] = {STACK_OFFSET(40), STACK_OFFSET(44)},
146
147 /* Callee saved registers that in-kernel function will preserve */
148 /* Stored on stack scratch space */
149 [BPF_REG_6] = {STACK_OFFSET(48), STACK_OFFSET(52)},
150 [BPF_REG_7] = {STACK_OFFSET(56), STACK_OFFSET(60)},
151 [BPF_REG_8] = {STACK_OFFSET(64), STACK_OFFSET(68)},
152 [BPF_REG_9] = {STACK_OFFSET(72), STACK_OFFSET(76)},
153
154 /* Read only Frame Pointer to access Stack */
155 [BPF_REG_FP] = {STACK_OFFSET(80), STACK_OFFSET(84)},
156
157 /* Temporary register for blinding constants. */
158 [BPF_REG_AX] = {IA32_ESI, IA32_EDI},
159
160 /* Tail call count. Stored on stack scratch space. */
161 [TCALL_CNT] = {STACK_OFFSET(88), STACK_OFFSET(92)},
162};
163
164#define dst_lo dst[0]
165#define dst_hi dst[1]
166#define src_lo src[0]
167#define src_hi src[1]
168
169#define STACK_ALIGNMENT 8
170/*
171 * Stack space for BPF_REG_1, BPF_REG_2, BPF_REG_3, BPF_REG_4,
172 * BPF_REG_5, BPF_REG_6, BPF_REG_7, BPF_REG_8, BPF_REG_9,
173 * BPF_REG_FP, BPF_REG_AX and Tail call counts.
174 */
175#define SCRATCH_SIZE 96
176
177/* Total stack size used in JITed code */
178#define _STACK_SIZE (stack_depth + SCRATCH_SIZE)
179
180#define STACK_SIZE ALIGN(_STACK_SIZE, STACK_ALIGNMENT)
181
182/* Get the offset of eBPF REGISTERs stored on scratch space. */
183#define STACK_VAR(off) (off)
184
185/* Encode 'dst_reg' register into IA32 opcode 'byte' */
186static u8 add_1reg(u8 byte, u32 dst_reg)
187{
188 return byte + dst_reg;
189}
190
191/* Encode 'dst_reg' and 'src_reg' registers into IA32 opcode 'byte' */
192static u8 add_2reg(u8 byte, u32 dst_reg, u32 src_reg)
193{
194 return byte + dst_reg + (src_reg << 3);
195}
196
197static void jit_fill_hole(void *area, unsigned int size)
198{
199 /* Fill whole space with int3 instructions */
200 memset(area, 0xcc, size);
201}
202
203static inline void emit_ia32_mov_i(const u8 dst, const u32 val, bool dstk,
204 u8 **pprog)
205{
206 u8 *prog = *pprog;
207 int cnt = 0;
208
209 if (dstk) {
210 if (val == 0) {
211 /* xor eax,eax */
212 EMIT2(0x33, add_2reg(0xC0, IA32_EAX, IA32_EAX));
213 /* mov dword ptr [ebp+off],eax */
214 EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EAX),
215 STACK_VAR(dst));
216 } else {
217 EMIT3_off32(0xC7, add_1reg(0x40, IA32_EBP),
218 STACK_VAR(dst), val);
219 }
220 } else {
221 if (val == 0)
222 EMIT2(0x33, add_2reg(0xC0, dst, dst));
223 else
224 EMIT2_off32(0xC7, add_1reg(0xC0, dst),
225 val);
226 }
227 *pprog = prog;
228}
229
230/* dst = imm (4 bytes)*/
231static inline void emit_ia32_mov_r(const u8 dst, const u8 src, bool dstk,
232 bool sstk, u8 **pprog)
233{
234 u8 *prog = *pprog;
235 int cnt = 0;
236 u8 sreg = sstk ? IA32_EAX : src;
237
238 if (sstk)
239 /* mov eax,dword ptr [ebp+off] */
240 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX), STACK_VAR(src));
241 if (dstk)
242 /* mov dword ptr [ebp+off],eax */
243 EMIT3(0x89, add_2reg(0x40, IA32_EBP, sreg), STACK_VAR(dst));
244 else
245 /* mov dst,sreg */
246 EMIT2(0x89, add_2reg(0xC0, dst, sreg));
247
248 *pprog = prog;
249}
250
251/* dst = src */
252static inline void emit_ia32_mov_r64(const bool is64, const u8 dst[],
253 const u8 src[], bool dstk,
254 bool sstk, u8 **pprog)
255{
256 emit_ia32_mov_r(dst_lo, src_lo, dstk, sstk, pprog);
257 if (is64)
258 /* complete 8 byte move */
259 emit_ia32_mov_r(dst_hi, src_hi, dstk, sstk, pprog);
260 else
261 /* zero out high 4 bytes */
262 emit_ia32_mov_i(dst_hi, 0, dstk, pprog);
263}
264
265/* Sign extended move */
266static inline void emit_ia32_mov_i64(const bool is64, const u8 dst[],
267 const u32 val, bool dstk, u8 **pprog)
268{
269 u32 hi = 0;
270
271 if (is64 && (val & (1<<31)))
272 hi = (u32)~0;
273 emit_ia32_mov_i(dst_lo, val, dstk, pprog);
274 emit_ia32_mov_i(dst_hi, hi, dstk, pprog);
275}
276
277/*
278 * ALU operation (32 bit)
279 * dst = dst * src
280 */
281static inline void emit_ia32_mul_r(const u8 dst, const u8 src, bool dstk,
282 bool sstk, u8 **pprog)
283{
284 u8 *prog = *pprog;
285 int cnt = 0;
286 u8 sreg = sstk ? IA32_ECX : src;
287
288 if (sstk)
289 /* mov ecx,dword ptr [ebp+off] */
290 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_ECX), STACK_VAR(src));
291
292 if (dstk)
293 /* mov eax,dword ptr [ebp+off] */
294 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX), STACK_VAR(dst));
295 else
296 /* mov eax,dst */
297 EMIT2(0x8B, add_2reg(0xC0, dst, IA32_EAX));
298
299
300 EMIT2(0xF7, add_1reg(0xE0, sreg));
301
302 if (dstk)
303 /* mov dword ptr [ebp+off],eax */
304 EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EAX),
305 STACK_VAR(dst));
306 else
307 /* mov dst,eax */
308 EMIT2(0x89, add_2reg(0xC0, dst, IA32_EAX));
309
310 *pprog = prog;
311}
312
313static inline void emit_ia32_to_le_r64(const u8 dst[], s32 val,
314 bool dstk, u8 **pprog)
315{
316 u8 *prog = *pprog;
317 int cnt = 0;
318 u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
319 u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
320
321 if (dstk && val != 64) {
322 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
323 STACK_VAR(dst_lo));
324 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
325 STACK_VAR(dst_hi));
326 }
327 switch (val) {
328 case 16:
329 /*
330 * Emit 'movzwl eax,ax' to zero extend 16-bit
331 * into 64 bit
332 */
333 EMIT2(0x0F, 0xB7);
334 EMIT1(add_2reg(0xC0, dreg_lo, dreg_lo));
335 /* xor dreg_hi,dreg_hi */
336 EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
337 break;
338 case 32:
339 /* xor dreg_hi,dreg_hi */
340 EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
341 break;
342 case 64:
343 /* nop */
344 break;
345 }
346
347 if (dstk && val != 64) {
348 /* mov dword ptr [ebp+off],dreg_lo */
349 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_lo),
350 STACK_VAR(dst_lo));
351 /* mov dword ptr [ebp+off],dreg_hi */
352 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_hi),
353 STACK_VAR(dst_hi));
354 }
355 *pprog = prog;
356}
357
358static inline void emit_ia32_to_be_r64(const u8 dst[], s32 val,
359 bool dstk, u8 **pprog)
360{
361 u8 *prog = *pprog;
362 int cnt = 0;
363 u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
364 u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
365
366 if (dstk) {
367 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
368 STACK_VAR(dst_lo));
369 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
370 STACK_VAR(dst_hi));
371 }
372 switch (val) {
373 case 16:
374 /* Emit 'ror %ax, 8' to swap lower 2 bytes */
375 EMIT1(0x66);
376 EMIT3(0xC1, add_1reg(0xC8, dreg_lo), 8);
377
378 EMIT2(0x0F, 0xB7);
379 EMIT1(add_2reg(0xC0, dreg_lo, dreg_lo));
380
381 /* xor dreg_hi,dreg_hi */
382 EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
383 break;
384 case 32:
385 /* Emit 'bswap eax' to swap lower 4 bytes */
386 EMIT1(0x0F);
387 EMIT1(add_1reg(0xC8, dreg_lo));
388
389 /* xor dreg_hi,dreg_hi */
390 EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
391 break;
392 case 64:
393 /* Emit 'bswap eax' to swap lower 4 bytes */
394 EMIT1(0x0F);
395 EMIT1(add_1reg(0xC8, dreg_lo));
396
397 /* Emit 'bswap edx' to swap lower 4 bytes */
398 EMIT1(0x0F);
399 EMIT1(add_1reg(0xC8, dreg_hi));
400
401 /* mov ecx,dreg_hi */
402 EMIT2(0x89, add_2reg(0xC0, IA32_ECX, dreg_hi));
403 /* mov dreg_hi,dreg_lo */
404 EMIT2(0x89, add_2reg(0xC0, dreg_hi, dreg_lo));
405 /* mov dreg_lo,ecx */
406 EMIT2(0x89, add_2reg(0xC0, dreg_lo, IA32_ECX));
407
408 break;
409 }
410 if (dstk) {
411 /* mov dword ptr [ebp+off],dreg_lo */
412 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_lo),
413 STACK_VAR(dst_lo));
414 /* mov dword ptr [ebp+off],dreg_hi */
415 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_hi),
416 STACK_VAR(dst_hi));
417 }
418 *pprog = prog;
419}
420
421/*
422 * ALU operation (32 bit)
423 * dst = dst (div|mod) src
424 */
425static inline void emit_ia32_div_mod_r(const u8 op, const u8 dst, const u8 src,
426 bool dstk, bool sstk, u8 **pprog)
427{
428 u8 *prog = *pprog;
429 int cnt = 0;
430
431 if (sstk)
432 /* mov ecx,dword ptr [ebp+off] */
433 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_ECX),
434 STACK_VAR(src));
435 else if (src != IA32_ECX)
436 /* mov ecx,src */
437 EMIT2(0x8B, add_2reg(0xC0, src, IA32_ECX));
438
439 if (dstk)
440 /* mov eax,dword ptr [ebp+off] */
441 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
442 STACK_VAR(dst));
443 else
444 /* mov eax,dst */
445 EMIT2(0x8B, add_2reg(0xC0, dst, IA32_EAX));
446
447 /* xor edx,edx */
448 EMIT2(0x31, add_2reg(0xC0, IA32_EDX, IA32_EDX));
449 /* div ecx */
450 EMIT2(0xF7, add_1reg(0xF0, IA32_ECX));
451
452 if (op == BPF_MOD) {
453 if (dstk)
454 EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EDX),
455 STACK_VAR(dst));
456 else
457 EMIT2(0x89, add_2reg(0xC0, dst, IA32_EDX));
458 } else {
459 if (dstk)
460 EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EAX),
461 STACK_VAR(dst));
462 else
463 EMIT2(0x89, add_2reg(0xC0, dst, IA32_EAX));
464 }
465 *pprog = prog;
466}
467
468/*
469 * ALU operation (32 bit)
470 * dst = dst (shift) src
471 */
472static inline void emit_ia32_shift_r(const u8 op, const u8 dst, const u8 src,
473 bool dstk, bool sstk, u8 **pprog)
474{
475 u8 *prog = *pprog;
476 int cnt = 0;
477 u8 dreg = dstk ? IA32_EAX : dst;
478 u8 b2;
479
480 if (dstk)
481 /* mov eax,dword ptr [ebp+off] */
482 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX), STACK_VAR(dst));
483
484 if (sstk)
485 /* mov ecx,dword ptr [ebp+off] */
486 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_ECX), STACK_VAR(src));
487 else if (src != IA32_ECX)
488 /* mov ecx,src */
489 EMIT2(0x8B, add_2reg(0xC0, src, IA32_ECX));
490
491 switch (op) {
492 case BPF_LSH:
493 b2 = 0xE0; break;
494 case BPF_RSH:
495 b2 = 0xE8; break;
496 case BPF_ARSH:
497 b2 = 0xF8; break;
498 default:
499 return;
500 }
501 EMIT2(0xD3, add_1reg(b2, dreg));
502
503 if (dstk)
504 /* mov dword ptr [ebp+off],dreg */
505 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg), STACK_VAR(dst));
506 *pprog = prog;
507}
508
509/*
510 * ALU operation (32 bit)
511 * dst = dst (op) src
512 */
513static inline void emit_ia32_alu_r(const bool is64, const bool hi, const u8 op,
514 const u8 dst, const u8 src, bool dstk,
515 bool sstk, u8 **pprog)
516{
517 u8 *prog = *pprog;
518 int cnt = 0;
519 u8 sreg = sstk ? IA32_EAX : src;
520 u8 dreg = dstk ? IA32_EDX : dst;
521
522 if (sstk)
523 /* mov eax,dword ptr [ebp+off] */
524 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX), STACK_VAR(src));
525
526 if (dstk)
527 /* mov eax,dword ptr [ebp+off] */
528 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX), STACK_VAR(dst));
529
530 switch (BPF_OP(op)) {
531 /* dst = dst + src */
532 case BPF_ADD:
533 if (hi && is64)
534 EMIT2(0x11, add_2reg(0xC0, dreg, sreg));
535 else
536 EMIT2(0x01, add_2reg(0xC0, dreg, sreg));
537 break;
538 /* dst = dst - src */
539 case BPF_SUB:
540 if (hi && is64)
541 EMIT2(0x19, add_2reg(0xC0, dreg, sreg));
542 else
543 EMIT2(0x29, add_2reg(0xC0, dreg, sreg));
544 break;
545 /* dst = dst | src */
546 case BPF_OR:
547 EMIT2(0x09, add_2reg(0xC0, dreg, sreg));
548 break;
549 /* dst = dst & src */
550 case BPF_AND:
551 EMIT2(0x21, add_2reg(0xC0, dreg, sreg));
552 break;
553 /* dst = dst ^ src */
554 case BPF_XOR:
555 EMIT2(0x31, add_2reg(0xC0, dreg, sreg));
556 break;
557 }
558
559 if (dstk)
560 /* mov dword ptr [ebp+off],dreg */
561 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg),
562 STACK_VAR(dst));
563 *pprog = prog;
564}
565
566/* ALU operation (64 bit) */
567static inline void emit_ia32_alu_r64(const bool is64, const u8 op,
568 const u8 dst[], const u8 src[],
569 bool dstk, bool sstk,
570 u8 **pprog)
571{
572 u8 *prog = *pprog;
573
574 emit_ia32_alu_r(is64, false, op, dst_lo, src_lo, dstk, sstk, &prog);
575 if (is64)
576 emit_ia32_alu_r(is64, true, op, dst_hi, src_hi, dstk, sstk,
577 &prog);
578 else
579 emit_ia32_mov_i(dst_hi, 0, dstk, &prog);
580 *pprog = prog;
581}
582
583/*
584 * ALU operation (32 bit)
585 * dst = dst (op) val
586 */
587static inline void emit_ia32_alu_i(const bool is64, const bool hi, const u8 op,
588 const u8 dst, const s32 val, bool dstk,
589 u8 **pprog)
590{
591 u8 *prog = *pprog;
592 int cnt = 0;
593 u8 dreg = dstk ? IA32_EAX : dst;
594 u8 sreg = IA32_EDX;
595
596 if (dstk)
597 /* mov eax,dword ptr [ebp+off] */
598 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX), STACK_VAR(dst));
599
600 if (!is_imm8(val))
601 /* mov edx,imm32*/
602 EMIT2_off32(0xC7, add_1reg(0xC0, IA32_EDX), val);
603
604 switch (op) {
605 /* dst = dst + val */
606 case BPF_ADD:
607 if (hi && is64) {
608 if (is_imm8(val))
609 EMIT3(0x83, add_1reg(0xD0, dreg), val);
610 else
611 EMIT2(0x11, add_2reg(0xC0, dreg, sreg));
612 } else {
613 if (is_imm8(val))
614 EMIT3(0x83, add_1reg(0xC0, dreg), val);
615 else
616 EMIT2(0x01, add_2reg(0xC0, dreg, sreg));
617 }
618 break;
619 /* dst = dst - val */
620 case BPF_SUB:
621 if (hi && is64) {
622 if (is_imm8(val))
623 EMIT3(0x83, add_1reg(0xD8, dreg), val);
624 else
625 EMIT2(0x19, add_2reg(0xC0, dreg, sreg));
626 } else {
627 if (is_imm8(val))
628 EMIT3(0x83, add_1reg(0xE8, dreg), val);
629 else
630 EMIT2(0x29, add_2reg(0xC0, dreg, sreg));
631 }
632 break;
633 /* dst = dst | val */
634 case BPF_OR:
635 if (is_imm8(val))
636 EMIT3(0x83, add_1reg(0xC8, dreg), val);
637 else
638 EMIT2(0x09, add_2reg(0xC0, dreg, sreg));
639 break;
640 /* dst = dst & val */
641 case BPF_AND:
642 if (is_imm8(val))
643 EMIT3(0x83, add_1reg(0xE0, dreg), val);
644 else
645 EMIT2(0x21, add_2reg(0xC0, dreg, sreg));
646 break;
647 /* dst = dst ^ val */
648 case BPF_XOR:
649 if (is_imm8(val))
650 EMIT3(0x83, add_1reg(0xF0, dreg), val);
651 else
652 EMIT2(0x31, add_2reg(0xC0, dreg, sreg));
653 break;
654 case BPF_NEG:
655 EMIT2(0xF7, add_1reg(0xD8, dreg));
656 break;
657 }
658
659 if (dstk)
660 /* mov dword ptr [ebp+off],dreg */
661 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg),
662 STACK_VAR(dst));
663 *pprog = prog;
664}
665
666/* ALU operation (64 bit) */
667static inline void emit_ia32_alu_i64(const bool is64, const u8 op,
668 const u8 dst[], const u32 val,
669 bool dstk, u8 **pprog)
670{
671 u8 *prog = *pprog;
672 u32 hi = 0;
673
674 if (is64 && (val & (1<<31)))
675 hi = (u32)~0;
676
677 emit_ia32_alu_i(is64, false, op, dst_lo, val, dstk, &prog);
678 if (is64)
679 emit_ia32_alu_i(is64, true, op, dst_hi, hi, dstk, &prog);
680 else
681 emit_ia32_mov_i(dst_hi, 0, dstk, &prog);
682
683 *pprog = prog;
684}
685
686/* dst = ~dst (64 bit) */
687static inline void emit_ia32_neg64(const u8 dst[], bool dstk, u8 **pprog)
688{
689 u8 *prog = *pprog;
690 int cnt = 0;
691 u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
692 u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
693
694 if (dstk) {
695 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
696 STACK_VAR(dst_lo));
697 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
698 STACK_VAR(dst_hi));
699 }
700
701 /* xor ecx,ecx */
702 EMIT2(0x31, add_2reg(0xC0, IA32_ECX, IA32_ECX));
703 /* sub dreg_lo,ecx */
704 EMIT2(0x2B, add_2reg(0xC0, dreg_lo, IA32_ECX));
705 /* mov dreg_lo,ecx */
706 EMIT2(0x89, add_2reg(0xC0, dreg_lo, IA32_ECX));
707
708 /* xor ecx,ecx */
709 EMIT2(0x31, add_2reg(0xC0, IA32_ECX, IA32_ECX));
710 /* sbb dreg_hi,ecx */
711 EMIT2(0x19, add_2reg(0xC0, dreg_hi, IA32_ECX));
712 /* mov dreg_hi,ecx */
713 EMIT2(0x89, add_2reg(0xC0, dreg_hi, IA32_ECX));
714
715 if (dstk) {
716 /* mov dword ptr [ebp+off],dreg_lo */
717 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_lo),
718 STACK_VAR(dst_lo));
719 /* mov dword ptr [ebp+off],dreg_hi */
720 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_hi),
721 STACK_VAR(dst_hi));
722 }
723 *pprog = prog;
724}
725
726/* dst = dst << src */
727static inline void emit_ia32_lsh_r64(const u8 dst[], const u8 src[],
728 bool dstk, bool sstk, u8 **pprog)
729{
730 u8 *prog = *pprog;
731 int cnt = 0;
732 static int jmp_label1 = -1;
733 static int jmp_label2 = -1;
734 static int jmp_label3 = -1;
735 u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
736 u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
737
738 if (dstk) {
739 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
740 STACK_VAR(dst_lo));
741 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
742 STACK_VAR(dst_hi));
743 }
744
745 if (sstk)
746 /* mov ecx,dword ptr [ebp+off] */
747 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_ECX),
748 STACK_VAR(src_lo));
749 else
750 /* mov ecx,src_lo */
751 EMIT2(0x8B, add_2reg(0xC0, src_lo, IA32_ECX));
752
753 /* cmp ecx,32 */
754 EMIT3(0x83, add_1reg(0xF8, IA32_ECX), 32);
755 /* Jumps when >= 32 */
756 if (is_imm8(jmp_label(jmp_label1, 2)))
757 EMIT2(IA32_JAE, jmp_label(jmp_label1, 2));
758 else
759 EMIT2_off32(0x0F, IA32_JAE + 0x10, jmp_label(jmp_label1, 6));
760
761 /* < 32 */
762 /* shl dreg_hi,cl */
763 EMIT2(0xD3, add_1reg(0xE0, dreg_hi));
764 /* mov ebx,dreg_lo */
765 EMIT2(0x8B, add_2reg(0xC0, dreg_lo, IA32_EBX));
766 /* shl dreg_lo,cl */
767 EMIT2(0xD3, add_1reg(0xE0, dreg_lo));
768
769 /* IA32_ECX = -IA32_ECX + 32 */
770 /* neg ecx */
771 EMIT2(0xF7, add_1reg(0xD8, IA32_ECX));
772 /* add ecx,32 */
773 EMIT3(0x83, add_1reg(0xC0, IA32_ECX), 32);
774
775 /* shr ebx,cl */
776 EMIT2(0xD3, add_1reg(0xE8, IA32_EBX));
777 /* or dreg_hi,ebx */
778 EMIT2(0x09, add_2reg(0xC0, dreg_hi, IA32_EBX));
779
780 /* goto out; */
781 if (is_imm8(jmp_label(jmp_label3, 2)))
782 EMIT2(0xEB, jmp_label(jmp_label3, 2));
783 else
784 EMIT1_off32(0xE9, jmp_label(jmp_label3, 5));
785
786 /* >= 32 */
787 if (jmp_label1 == -1)
788 jmp_label1 = cnt;
789
790 /* cmp ecx,64 */
791 EMIT3(0x83, add_1reg(0xF8, IA32_ECX), 64);
792 /* Jumps when >= 64 */
793 if (is_imm8(jmp_label(jmp_label2, 2)))
794 EMIT2(IA32_JAE, jmp_label(jmp_label2, 2));
795 else
796 EMIT2_off32(0x0F, IA32_JAE + 0x10, jmp_label(jmp_label2, 6));
797
798 /* >= 32 && < 64 */
799 /* sub ecx,32 */
800 EMIT3(0x83, add_1reg(0xE8, IA32_ECX), 32);
801 /* shl dreg_lo,cl */
802 EMIT2(0xD3, add_1reg(0xE0, dreg_lo));
803 /* mov dreg_hi,dreg_lo */
804 EMIT2(0x89, add_2reg(0xC0, dreg_hi, dreg_lo));
805
806 /* xor dreg_lo,dreg_lo */
807 EMIT2(0x33, add_2reg(0xC0, dreg_lo, dreg_lo));
808
809 /* goto out; */
810 if (is_imm8(jmp_label(jmp_label3, 2)))
811 EMIT2(0xEB, jmp_label(jmp_label3, 2));
812 else
813 EMIT1_off32(0xE9, jmp_label(jmp_label3, 5));
814
815 /* >= 64 */
816 if (jmp_label2 == -1)
817 jmp_label2 = cnt;
818 /* xor dreg_lo,dreg_lo */
819 EMIT2(0x33, add_2reg(0xC0, dreg_lo, dreg_lo));
820 /* xor dreg_hi,dreg_hi */
821 EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
822
823 if (jmp_label3 == -1)
824 jmp_label3 = cnt;
825
826 if (dstk) {
827 /* mov dword ptr [ebp+off],dreg_lo */
828 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_lo),
829 STACK_VAR(dst_lo));
830 /* mov dword ptr [ebp+off],dreg_hi */
831 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_hi),
832 STACK_VAR(dst_hi));
833 }
834 /* out: */
835 *pprog = prog;
836}
837
838/* dst = dst >> src (signed)*/
839static inline void emit_ia32_arsh_r64(const u8 dst[], const u8 src[],
840 bool dstk, bool sstk, u8 **pprog)
841{
842 u8 *prog = *pprog;
843 int cnt = 0;
844 static int jmp_label1 = -1;
845 static int jmp_label2 = -1;
846 static int jmp_label3 = -1;
847 u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
848 u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
849
850 if (dstk) {
851 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
852 STACK_VAR(dst_lo));
853 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
854 STACK_VAR(dst_hi));
855 }
856
857 if (sstk)
858 /* mov ecx,dword ptr [ebp+off] */
859 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_ECX),
860 STACK_VAR(src_lo));
861 else
862 /* mov ecx,src_lo */
863 EMIT2(0x8B, add_2reg(0xC0, src_lo, IA32_ECX));
864
865 /* cmp ecx,32 */
866 EMIT3(0x83, add_1reg(0xF8, IA32_ECX), 32);
867 /* Jumps when >= 32 */
868 if (is_imm8(jmp_label(jmp_label1, 2)))
869 EMIT2(IA32_JAE, jmp_label(jmp_label1, 2));
870 else
871 EMIT2_off32(0x0F, IA32_JAE + 0x10, jmp_label(jmp_label1, 6));
872
873 /* < 32 */
874 /* lshr dreg_lo,cl */
875 EMIT2(0xD3, add_1reg(0xE8, dreg_lo));
876 /* mov ebx,dreg_hi */
877 EMIT2(0x8B, add_2reg(0xC0, dreg_hi, IA32_EBX));
878 /* ashr dreg_hi,cl */
879 EMIT2(0xD3, add_1reg(0xF8, dreg_hi));
880
881 /* IA32_ECX = -IA32_ECX + 32 */
882 /* neg ecx */
883 EMIT2(0xF7, add_1reg(0xD8, IA32_ECX));
884 /* add ecx,32 */
885 EMIT3(0x83, add_1reg(0xC0, IA32_ECX), 32);
886
887 /* shl ebx,cl */
888 EMIT2(0xD3, add_1reg(0xE0, IA32_EBX));
889 /* or dreg_lo,ebx */
890 EMIT2(0x09, add_2reg(0xC0, dreg_lo, IA32_EBX));
891
892 /* goto out; */
893 if (is_imm8(jmp_label(jmp_label3, 2)))
894 EMIT2(0xEB, jmp_label(jmp_label3, 2));
895 else
896 EMIT1_off32(0xE9, jmp_label(jmp_label3, 5));
897
898 /* >= 32 */
899 if (jmp_label1 == -1)
900 jmp_label1 = cnt;
901
902 /* cmp ecx,64 */
903 EMIT3(0x83, add_1reg(0xF8, IA32_ECX), 64);
904 /* Jumps when >= 64 */
905 if (is_imm8(jmp_label(jmp_label2, 2)))
906 EMIT2(IA32_JAE, jmp_label(jmp_label2, 2));
907 else
908 EMIT2_off32(0x0F, IA32_JAE + 0x10, jmp_label(jmp_label2, 6));
909
910 /* >= 32 && < 64 */
911 /* sub ecx,32 */
912 EMIT3(0x83, add_1reg(0xE8, IA32_ECX), 32);
913 /* ashr dreg_hi,cl */
914 EMIT2(0xD3, add_1reg(0xF8, dreg_hi));
915 /* mov dreg_lo,dreg_hi */
916 EMIT2(0x89, add_2reg(0xC0, dreg_lo, dreg_hi));
917
918 /* ashr dreg_hi,imm8 */
919 EMIT3(0xC1, add_1reg(0xF8, dreg_hi), 31);
920
921 /* goto out; */
922 if (is_imm8(jmp_label(jmp_label3, 2)))
923 EMIT2(0xEB, jmp_label(jmp_label3, 2));
924 else
925 EMIT1_off32(0xE9, jmp_label(jmp_label3, 5));
926
927 /* >= 64 */
928 if (jmp_label2 == -1)
929 jmp_label2 = cnt;
930 /* ashr dreg_hi,imm8 */
931 EMIT3(0xC1, add_1reg(0xF8, dreg_hi), 31);
932 /* mov dreg_lo,dreg_hi */
933 EMIT2(0x89, add_2reg(0xC0, dreg_lo, dreg_hi));
934
935 if (jmp_label3 == -1)
936 jmp_label3 = cnt;
937
938 if (dstk) {
939 /* mov dword ptr [ebp+off],dreg_lo */
940 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_lo),
941 STACK_VAR(dst_lo));
942 /* mov dword ptr [ebp+off],dreg_hi */
943 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_hi),
944 STACK_VAR(dst_hi));
945 }
946 /* out: */
947 *pprog = prog;
948}
949
950/* dst = dst >> src */
951static inline void emit_ia32_rsh_r64(const u8 dst[], const u8 src[], bool dstk,
952 bool sstk, u8 **pprog)
953{
954 u8 *prog = *pprog;
955 int cnt = 0;
956 static int jmp_label1 = -1;
957 static int jmp_label2 = -1;
958 static int jmp_label3 = -1;
959 u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
960 u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
961
962 if (dstk) {
963 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
964 STACK_VAR(dst_lo));
965 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
966 STACK_VAR(dst_hi));
967 }
968
969 if (sstk)
970 /* mov ecx,dword ptr [ebp+off] */
971 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_ECX),
972 STACK_VAR(src_lo));
973 else
974 /* mov ecx,src_lo */
975 EMIT2(0x8B, add_2reg(0xC0, src_lo, IA32_ECX));
976
977 /* cmp ecx,32 */
978 EMIT3(0x83, add_1reg(0xF8, IA32_ECX), 32);
979 /* Jumps when >= 32 */
980 if (is_imm8(jmp_label(jmp_label1, 2)))
981 EMIT2(IA32_JAE, jmp_label(jmp_label1, 2));
982 else
983 EMIT2_off32(0x0F, IA32_JAE + 0x10, jmp_label(jmp_label1, 6));
984
985 /* < 32 */
986 /* lshr dreg_lo,cl */
987 EMIT2(0xD3, add_1reg(0xE8, dreg_lo));
988 /* mov ebx,dreg_hi */
989 EMIT2(0x8B, add_2reg(0xC0, dreg_hi, IA32_EBX));
990 /* shr dreg_hi,cl */
991 EMIT2(0xD3, add_1reg(0xE8, dreg_hi));
992
993 /* IA32_ECX = -IA32_ECX + 32 */
994 /* neg ecx */
995 EMIT2(0xF7, add_1reg(0xD8, IA32_ECX));
996 /* add ecx,32 */
997 EMIT3(0x83, add_1reg(0xC0, IA32_ECX), 32);
998
999 /* shl ebx,cl */
1000 EMIT2(0xD3, add_1reg(0xE0, IA32_EBX));
1001 /* or dreg_lo,ebx */
1002 EMIT2(0x09, add_2reg(0xC0, dreg_lo, IA32_EBX));
1003
1004 /* goto out; */
1005 if (is_imm8(jmp_label(jmp_label3, 2)))
1006 EMIT2(0xEB, jmp_label(jmp_label3, 2));
1007 else
1008 EMIT1_off32(0xE9, jmp_label(jmp_label3, 5));
1009
1010 /* >= 32 */
1011 if (jmp_label1 == -1)
1012 jmp_label1 = cnt;
1013 /* cmp ecx,64 */
1014 EMIT3(0x83, add_1reg(0xF8, IA32_ECX), 64);
1015 /* Jumps when >= 64 */
1016 if (is_imm8(jmp_label(jmp_label2, 2)))
1017 EMIT2(IA32_JAE, jmp_label(jmp_label2, 2));
1018 else
1019 EMIT2_off32(0x0F, IA32_JAE + 0x10, jmp_label(jmp_label2, 6));
1020
1021 /* >= 32 && < 64 */
1022 /* sub ecx,32 */
1023 EMIT3(0x83, add_1reg(0xE8, IA32_ECX), 32);
1024 /* shr dreg_hi,cl */
1025 EMIT2(0xD3, add_1reg(0xE8, dreg_hi));
1026 /* mov dreg_lo,dreg_hi */
1027 EMIT2(0x89, add_2reg(0xC0, dreg_lo, dreg_hi));
1028 /* xor dreg_hi,dreg_hi */
1029 EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
1030
1031 /* goto out; */
1032 if (is_imm8(jmp_label(jmp_label3, 2)))
1033 EMIT2(0xEB, jmp_label(jmp_label3, 2));
1034 else
1035 EMIT1_off32(0xE9, jmp_label(jmp_label3, 5));
1036
1037 /* >= 64 */
1038 if (jmp_label2 == -1)
1039 jmp_label2 = cnt;
1040 /* xor dreg_lo,dreg_lo */
1041 EMIT2(0x33, add_2reg(0xC0, dreg_lo, dreg_lo));
1042 /* xor dreg_hi,dreg_hi */
1043 EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
1044
1045 if (jmp_label3 == -1)
1046 jmp_label3 = cnt;
1047
1048 if (dstk) {
1049 /* mov dword ptr [ebp+off],dreg_lo */
1050 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_lo),
1051 STACK_VAR(dst_lo));
1052 /* mov dword ptr [ebp+off],dreg_hi */
1053 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_hi),
1054 STACK_VAR(dst_hi));
1055 }
1056 /* out: */
1057 *pprog = prog;
1058}
1059
1060/* dst = dst << val */
1061static inline void emit_ia32_lsh_i64(const u8 dst[], const u32 val,
1062 bool dstk, u8 **pprog)
1063{
1064 u8 *prog = *pprog;
1065 int cnt = 0;
1066 u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
1067 u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
1068
1069 if (dstk) {
1070 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
1071 STACK_VAR(dst_lo));
1072 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
1073 STACK_VAR(dst_hi));
1074 }
1075 /* Do LSH operation */
1076 if (val < 32) {
1077 /* shl dreg_hi,imm8 */
1078 EMIT3(0xC1, add_1reg(0xE0, dreg_hi), val);
1079 /* mov ebx,dreg_lo */
1080 EMIT2(0x8B, add_2reg(0xC0, dreg_lo, IA32_EBX));
1081 /* shl dreg_lo,imm8 */
1082 EMIT3(0xC1, add_1reg(0xE0, dreg_lo), val);
1083
1084 /* IA32_ECX = 32 - val */
1085 /* mov ecx,val */
1086 EMIT2(0xB1, val);
1087 /* movzx ecx,ecx */
1088 EMIT3(0x0F, 0xB6, add_2reg(0xC0, IA32_ECX, IA32_ECX));
1089 /* neg ecx */
1090 EMIT2(0xF7, add_1reg(0xD8, IA32_ECX));
1091 /* add ecx,32 */
1092 EMIT3(0x83, add_1reg(0xC0, IA32_ECX), 32);
1093
1094 /* shr ebx,cl */
1095 EMIT2(0xD3, add_1reg(0xE8, IA32_EBX));
1096 /* or dreg_hi,ebx */
1097 EMIT2(0x09, add_2reg(0xC0, dreg_hi, IA32_EBX));
1098 } else if (val >= 32 && val < 64) {
1099 u32 value = val - 32;
1100
1101 /* shl dreg_lo,imm8 */
1102 EMIT3(0xC1, add_1reg(0xE0, dreg_lo), value);
1103 /* mov dreg_hi,dreg_lo */
1104 EMIT2(0x89, add_2reg(0xC0, dreg_hi, dreg_lo));
1105 /* xor dreg_lo,dreg_lo */
1106 EMIT2(0x33, add_2reg(0xC0, dreg_lo, dreg_lo));
1107 } else {
1108 /* xor dreg_lo,dreg_lo */
1109 EMIT2(0x33, add_2reg(0xC0, dreg_lo, dreg_lo));
1110 /* xor dreg_hi,dreg_hi */
1111 EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
1112 }
1113
1114 if (dstk) {
1115 /* mov dword ptr [ebp+off],dreg_lo */
1116 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_lo),
1117 STACK_VAR(dst_lo));
1118 /* mov dword ptr [ebp+off],dreg_hi */
1119 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_hi),
1120 STACK_VAR(dst_hi));
1121 }
1122 *pprog = prog;
1123}
1124
1125/* dst = dst >> val */
1126static inline void emit_ia32_rsh_i64(const u8 dst[], const u32 val,
1127 bool dstk, u8 **pprog)
1128{
1129 u8 *prog = *pprog;
1130 int cnt = 0;
1131 u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
1132 u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
1133
1134 if (dstk) {
1135 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
1136 STACK_VAR(dst_lo));
1137 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
1138 STACK_VAR(dst_hi));
1139 }
1140
1141 /* Do RSH operation */
1142 if (val < 32) {
1143 /* shr dreg_lo,imm8 */
1144 EMIT3(0xC1, add_1reg(0xE8, dreg_lo), val);
1145 /* mov ebx,dreg_hi */
1146 EMIT2(0x8B, add_2reg(0xC0, dreg_hi, IA32_EBX));
1147 /* shr dreg_hi,imm8 */
1148 EMIT3(0xC1, add_1reg(0xE8, dreg_hi), val);
1149
1150 /* IA32_ECX = 32 - val */
1151 /* mov ecx,val */
1152 EMIT2(0xB1, val);
1153 /* movzx ecx,ecx */
1154 EMIT3(0x0F, 0xB6, add_2reg(0xC0, IA32_ECX, IA32_ECX));
1155 /* neg ecx */
1156 EMIT2(0xF7, add_1reg(0xD8, IA32_ECX));
1157 /* add ecx,32 */
1158 EMIT3(0x83, add_1reg(0xC0, IA32_ECX), 32);
1159
1160 /* shl ebx,cl */
1161 EMIT2(0xD3, add_1reg(0xE0, IA32_EBX));
1162 /* or dreg_lo,ebx */
1163 EMIT2(0x09, add_2reg(0xC0, dreg_lo, IA32_EBX));
1164 } else if (val >= 32 && val < 64) {
1165 u32 value = val - 32;
1166
1167 /* shr dreg_hi,imm8 */
1168 EMIT3(0xC1, add_1reg(0xE8, dreg_hi), value);
1169 /* mov dreg_lo,dreg_hi */
1170 EMIT2(0x89, add_2reg(0xC0, dreg_lo, dreg_hi));
1171 /* xor dreg_hi,dreg_hi */
1172 EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
1173 } else {
1174 /* xor dreg_lo,dreg_lo */
1175 EMIT2(0x33, add_2reg(0xC0, dreg_lo, dreg_lo));
1176 /* xor dreg_hi,dreg_hi */
1177 EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
1178 }
1179
1180 if (dstk) {
1181 /* mov dword ptr [ebp+off],dreg_lo */
1182 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_lo),
1183 STACK_VAR(dst_lo));
1184 /* mov dword ptr [ebp+off],dreg_hi */
1185 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_hi),
1186 STACK_VAR(dst_hi));
1187 }
1188 *pprog = prog;
1189}
1190
1191/* dst = dst >> val (signed) */
1192static inline void emit_ia32_arsh_i64(const u8 dst[], const u32 val,
1193 bool dstk, u8 **pprog)
1194{
1195 u8 *prog = *pprog;
1196 int cnt = 0;
1197 u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
1198 u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
1199
1200 if (dstk) {
1201 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
1202 STACK_VAR(dst_lo));
1203 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
1204 STACK_VAR(dst_hi));
1205 }
1206 /* Do RSH operation */
1207 if (val < 32) {
1208 /* shr dreg_lo,imm8 */
1209 EMIT3(0xC1, add_1reg(0xE8, dreg_lo), val);
1210 /* mov ebx,dreg_hi */
1211 EMIT2(0x8B, add_2reg(0xC0, dreg_hi, IA32_EBX));
1212 /* ashr dreg_hi,imm8 */
1213 EMIT3(0xC1, add_1reg(0xF8, dreg_hi), val);
1214
1215 /* IA32_ECX = 32 - val */
1216 /* mov ecx,val */
1217 EMIT2(0xB1, val);
1218 /* movzx ecx,ecx */
1219 EMIT3(0x0F, 0xB6, add_2reg(0xC0, IA32_ECX, IA32_ECX));
1220 /* neg ecx */
1221 EMIT2(0xF7, add_1reg(0xD8, IA32_ECX));
1222 /* add ecx,32 */
1223 EMIT3(0x83, add_1reg(0xC0, IA32_ECX), 32);
1224
1225 /* shl ebx,cl */
1226 EMIT2(0xD3, add_1reg(0xE0, IA32_EBX));
1227 /* or dreg_lo,ebx */
1228 EMIT2(0x09, add_2reg(0xC0, dreg_lo, IA32_EBX));
1229 } else if (val >= 32 && val < 64) {
1230 u32 value = val - 32;
1231
1232 /* ashr dreg_hi,imm8 */
1233 EMIT3(0xC1, add_1reg(0xF8, dreg_hi), value);
1234 /* mov dreg_lo,dreg_hi */
1235 EMIT2(0x89, add_2reg(0xC0, dreg_lo, dreg_hi));
1236
1237 /* ashr dreg_hi,imm8 */
1238 EMIT3(0xC1, add_1reg(0xF8, dreg_hi), 31);
1239 } else {
1240 /* ashr dreg_hi,imm8 */
1241 EMIT3(0xC1, add_1reg(0xF8, dreg_hi), 31);
1242 /* mov dreg_lo,dreg_hi */
1243 EMIT2(0x89, add_2reg(0xC0, dreg_lo, dreg_hi));
1244 }
1245
1246 if (dstk) {
1247 /* mov dword ptr [ebp+off],dreg_lo */
1248 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_lo),
1249 STACK_VAR(dst_lo));
1250 /* mov dword ptr [ebp+off],dreg_hi */
1251 EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_hi),
1252 STACK_VAR(dst_hi));
1253 }
1254 *pprog = prog;
1255}
1256
1257static inline void emit_ia32_mul_r64(const u8 dst[], const u8 src[], bool dstk,
1258 bool sstk, u8 **pprog)
1259{
1260 u8 *prog = *pprog;
1261 int cnt = 0;
1262
1263 if (dstk)
1264 /* mov eax,dword ptr [ebp+off] */
1265 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
1266 STACK_VAR(dst_hi));
1267 else
1268 /* mov eax,dst_hi */
1269 EMIT2(0x8B, add_2reg(0xC0, dst_hi, IA32_EAX));
1270
1271 if (sstk)
1272 /* mul dword ptr [ebp+off] */
1273 EMIT3(0xF7, add_1reg(0x60, IA32_EBP), STACK_VAR(src_lo));
1274 else
1275 /* mul src_lo */
1276 EMIT2(0xF7, add_1reg(0xE0, src_lo));
1277
1278 /* mov ecx,eax */
1279 EMIT2(0x89, add_2reg(0xC0, IA32_ECX, IA32_EAX));
1280
1281 if (dstk)
1282 /* mov eax,dword ptr [ebp+off] */
1283 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
1284 STACK_VAR(dst_lo));
1285 else
1286 /* mov eax,dst_lo */
1287 EMIT2(0x8B, add_2reg(0xC0, dst_lo, IA32_EAX));
1288
1289 if (sstk)
1290 /* mul dword ptr [ebp+off] */
1291 EMIT3(0xF7, add_1reg(0x60, IA32_EBP), STACK_VAR(src_hi));
1292 else
1293 /* mul src_hi */
1294 EMIT2(0xF7, add_1reg(0xE0, src_hi));
1295
1296 /* add eax,eax */
1297 EMIT2(0x01, add_2reg(0xC0, IA32_ECX, IA32_EAX));
1298
1299 if (dstk)
1300 /* mov eax,dword ptr [ebp+off] */
1301 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
1302 STACK_VAR(dst_lo));
1303 else
1304 /* mov eax,dst_lo */
1305 EMIT2(0x8B, add_2reg(0xC0, dst_lo, IA32_EAX));
1306
1307 if (sstk)
1308 /* mul dword ptr [ebp+off] */
1309 EMIT3(0xF7, add_1reg(0x60, IA32_EBP), STACK_VAR(src_lo));
1310 else
1311 /* mul src_lo */
1312 EMIT2(0xF7, add_1reg(0xE0, src_lo));
1313
1314 /* add ecx,edx */
1315 EMIT2(0x01, add_2reg(0xC0, IA32_ECX, IA32_EDX));
1316
1317 if (dstk) {
1318 /* mov dword ptr [ebp+off],eax */
1319 EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EAX),
1320 STACK_VAR(dst_lo));
1321 /* mov dword ptr [ebp+off],ecx */
1322 EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_ECX),
1323 STACK_VAR(dst_hi));
1324 } else {
1325 /* mov dst_lo,eax */
1326 EMIT2(0x89, add_2reg(0xC0, dst_lo, IA32_EAX));
1327 /* mov dst_hi,ecx */
1328 EMIT2(0x89, add_2reg(0xC0, dst_hi, IA32_ECX));
1329 }
1330
1331 *pprog = prog;
1332}
1333
1334static inline void emit_ia32_mul_i64(const u8 dst[], const u32 val,
1335 bool dstk, u8 **pprog)
1336{
1337 u8 *prog = *pprog;
1338 int cnt = 0;
1339 u32 hi;
1340
1341 hi = val & (1<<31) ? (u32)~0 : 0;
1342 /* movl eax,imm32 */
1343 EMIT2_off32(0xC7, add_1reg(0xC0, IA32_EAX), val);
1344 if (dstk)
1345 /* mul dword ptr [ebp+off] */
1346 EMIT3(0xF7, add_1reg(0x60, IA32_EBP), STACK_VAR(dst_hi));
1347 else
1348 /* mul dst_hi */
1349 EMIT2(0xF7, add_1reg(0xE0, dst_hi));
1350
1351 /* mov ecx,eax */
1352 EMIT2(0x89, add_2reg(0xC0, IA32_ECX, IA32_EAX));
1353
1354 /* movl eax,imm32 */
1355 EMIT2_off32(0xC7, add_1reg(0xC0, IA32_EAX), hi);
1356 if (dstk)
1357 /* mul dword ptr [ebp+off] */
1358 EMIT3(0xF7, add_1reg(0x60, IA32_EBP), STACK_VAR(dst_lo));
1359 else
1360 /* mul dst_lo */
1361 EMIT2(0xF7, add_1reg(0xE0, dst_lo));
1362 /* add ecx,eax */
1363 EMIT2(0x01, add_2reg(0xC0, IA32_ECX, IA32_EAX));
1364
1365 /* movl eax,imm32 */
1366 EMIT2_off32(0xC7, add_1reg(0xC0, IA32_EAX), val);
1367 if (dstk)
1368 /* mul dword ptr [ebp+off] */
1369 EMIT3(0xF7, add_1reg(0x60, IA32_EBP), STACK_VAR(dst_lo));
1370 else
1371 /* mul dst_lo */
1372 EMIT2(0xF7, add_1reg(0xE0, dst_lo));
1373
1374 /* add ecx,edx */
1375 EMIT2(0x01, add_2reg(0xC0, IA32_ECX, IA32_EDX));
1376
1377 if (dstk) {
1378 /* mov dword ptr [ebp+off],eax */
1379 EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EAX),
1380 STACK_VAR(dst_lo));
1381 /* mov dword ptr [ebp+off],ecx */
1382 EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_ECX),
1383 STACK_VAR(dst_hi));
1384 } else {
1385 /* mov dword ptr [ebp+off],eax */
1386 EMIT2(0x89, add_2reg(0xC0, dst_lo, IA32_EAX));
1387 /* mov dword ptr [ebp+off],ecx */
1388 EMIT2(0x89, add_2reg(0xC0, dst_hi, IA32_ECX));
1389 }
1390
1391 *pprog = prog;
1392}
1393
1394static int bpf_size_to_x86_bytes(int bpf_size)
1395{
1396 if (bpf_size == BPF_W)
1397 return 4;
1398 else if (bpf_size == BPF_H)
1399 return 2;
1400 else if (bpf_size == BPF_B)
1401 return 1;
1402 else if (bpf_size == BPF_DW)
1403 return 4; /* imm32 */
1404 else
1405 return 0;
1406}
1407
1408struct jit_context {
1409 int cleanup_addr; /* Epilogue code offset */
1410};
1411
1412/* Maximum number of bytes emitted while JITing one eBPF insn */
1413#define BPF_MAX_INSN_SIZE 128
1414#define BPF_INSN_SAFETY 64
1415
1416#define PROLOGUE_SIZE 35
1417
1418/*
1419 * Emit prologue code for BPF program and check it's size.
1420 * bpf_tail_call helper will skip it while jumping into another program.
1421 */
1422static void emit_prologue(u8 **pprog, u32 stack_depth)
1423{
1424 u8 *prog = *pprog;
1425 int cnt = 0;
1426 const u8 *r1 = bpf2ia32[BPF_REG_1];
1427 const u8 fplo = bpf2ia32[BPF_REG_FP][0];
1428 const u8 fphi = bpf2ia32[BPF_REG_FP][1];
1429 const u8 *tcc = bpf2ia32[TCALL_CNT];
1430
1431 /* push ebp */
1432 EMIT1(0x55);
1433 /* mov ebp,esp */
1434 EMIT2(0x89, 0xE5);
1435 /* push edi */
1436 EMIT1(0x57);
1437 /* push esi */
1438 EMIT1(0x56);
1439 /* push ebx */
1440 EMIT1(0x53);
1441
1442 /* sub esp,STACK_SIZE */
1443 EMIT2_off32(0x81, 0xEC, STACK_SIZE);
1444 /* sub ebp,SCRATCH_SIZE+4+12*/
1445 EMIT3(0x83, add_1reg(0xE8, IA32_EBP), SCRATCH_SIZE + 16);
1446 /* xor ebx,ebx */
1447 EMIT2(0x31, add_2reg(0xC0, IA32_EBX, IA32_EBX));
1448
1449 /* Set up BPF prog stack base register */
1450 EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EBP), STACK_VAR(fplo));
1451 EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EBX), STACK_VAR(fphi));
1452
1453 /* Move BPF_CTX (EAX) to BPF_REG_R1 */
1454 /* mov dword ptr [ebp+off],eax */
1455 EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EAX), STACK_VAR(r1[0]));
1456 EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EBX), STACK_VAR(r1[1]));
1457
1458 /* Initialize Tail Count */
1459 EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EBX), STACK_VAR(tcc[0]));
1460 EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EBX), STACK_VAR(tcc[1]));
1461
1462 BUILD_BUG_ON(cnt != PROLOGUE_SIZE);
1463 *pprog = prog;
1464}
1465
1466/* Emit epilogue code for BPF program */
1467static void emit_epilogue(u8 **pprog, u32 stack_depth)
1468{
1469 u8 *prog = *pprog;
1470 const u8 *r0 = bpf2ia32[BPF_REG_0];
1471 int cnt = 0;
1472
1473 /* mov eax,dword ptr [ebp+off]*/
1474 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX), STACK_VAR(r0[0]));
1475 /* mov edx,dword ptr [ebp+off]*/
1476 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX), STACK_VAR(r0[1]));
1477
1478 /* add ebp,SCRATCH_SIZE+4+12*/
1479 EMIT3(0x83, add_1reg(0xC0, IA32_EBP), SCRATCH_SIZE + 16);
1480
1481 /* mov ebx,dword ptr [ebp-12]*/
1482 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EBX), -12);
1483 /* mov esi,dword ptr [ebp-8]*/
1484 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_ESI), -8);
1485 /* mov edi,dword ptr [ebp-4]*/
1486 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDI), -4);
1487
1488 EMIT1(0xC9); /* leave */
1489 EMIT1(0xC3); /* ret */
1490 *pprog = prog;
1491}
1492
1493/*
1494 * Generate the following code:
1495 * ... bpf_tail_call(void *ctx, struct bpf_array *array, u64 index) ...
1496 * if (index >= array->map.max_entries)
1497 * goto out;
1498 * if (++tail_call_cnt > MAX_TAIL_CALL_CNT)
1499 * goto out;
1500 * prog = array->ptrs[index];
1501 * if (prog == NULL)
1502 * goto out;
1503 * goto *(prog->bpf_func + prologue_size);
1504 * out:
1505 */
1506static void emit_bpf_tail_call(u8 **pprog)
1507{
1508 u8 *prog = *pprog;
1509 int cnt = 0;
1510 const u8 *r1 = bpf2ia32[BPF_REG_1];
1511 const u8 *r2 = bpf2ia32[BPF_REG_2];
1512 const u8 *r3 = bpf2ia32[BPF_REG_3];
1513 const u8 *tcc = bpf2ia32[TCALL_CNT];
1514 u32 lo, hi;
1515 static int jmp_label1 = -1;
1516
1517 /*
1518 * if (index >= array->map.max_entries)
1519 * goto out;
1520 */
1521 /* mov eax,dword ptr [ebp+off] */
1522 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX), STACK_VAR(r2[0]));
1523 /* mov edx,dword ptr [ebp+off] */
1524 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX), STACK_VAR(r3[0]));
1525
1526 /* cmp dword ptr [eax+off],edx */
1527 EMIT3(0x39, add_2reg(0x40, IA32_EAX, IA32_EDX),
1528 offsetof(struct bpf_array, map.max_entries));
1529 /* jbe out */
1530 EMIT2(IA32_JBE, jmp_label(jmp_label1, 2));
1531
1532 /*
1533 * if (tail_call_cnt > MAX_TAIL_CALL_CNT)
1534 * goto out;
1535 */
1536 lo = (u32)MAX_TAIL_CALL_CNT;
1537 hi = (u32)((u64)MAX_TAIL_CALL_CNT >> 32);
1538 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_ECX), STACK_VAR(tcc[0]));
1539 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EBX), STACK_VAR(tcc[1]));
1540
1541 /* cmp edx,hi */
1542 EMIT3(0x83, add_1reg(0xF8, IA32_EBX), hi);
1543 EMIT2(IA32_JNE, 3);
1544 /* cmp ecx,lo */
1545 EMIT3(0x83, add_1reg(0xF8, IA32_ECX), lo);
1546
1547 /* ja out */
1548 EMIT2(IA32_JAE, jmp_label(jmp_label1, 2));
1549
1550 /* add eax,0x1 */
1551 EMIT3(0x83, add_1reg(0xC0, IA32_ECX), 0x01);
1552 /* adc ebx,0x0 */
1553 EMIT3(0x83, add_1reg(0xD0, IA32_EBX), 0x00);
1554
1555 /* mov dword ptr [ebp+off],eax */
1556 EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_ECX), STACK_VAR(tcc[0]));
1557 /* mov dword ptr [ebp+off],edx */
1558 EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EBX), STACK_VAR(tcc[1]));
1559
1560 /* prog = array->ptrs[index]; */
1561 /* mov edx, [eax + edx * 4 + offsetof(...)] */
1562 EMIT3_off32(0x8B, 0x94, 0x90, offsetof(struct bpf_array, ptrs));
1563
1564 /*
1565 * if (prog == NULL)
1566 * goto out;
1567 */
1568 /* test edx,edx */
1569 EMIT2(0x85, add_2reg(0xC0, IA32_EDX, IA32_EDX));
1570 /* je out */
1571 EMIT2(IA32_JE, jmp_label(jmp_label1, 2));
1572
1573 /* goto *(prog->bpf_func + prologue_size); */
1574 /* mov edx, dword ptr [edx + 32] */
1575 EMIT3(0x8B, add_2reg(0x40, IA32_EDX, IA32_EDX),
1576 offsetof(struct bpf_prog, bpf_func));
1577 /* add edx,prologue_size */
1578 EMIT3(0x83, add_1reg(0xC0, IA32_EDX), PROLOGUE_SIZE);
1579
1580 /* mov eax,dword ptr [ebp+off] */
1581 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX), STACK_VAR(r1[0]));
1582
1583 /*
1584 * Now we're ready to jump into next BPF program:
1585 * eax == ctx (1st arg)
1586 * edx == prog->bpf_func + prologue_size
1587 */
1588 RETPOLINE_EDX_BPF_JIT();
1589
1590 if (jmp_label1 == -1)
1591 jmp_label1 = cnt;
1592
1593 /* out: */
1594 *pprog = prog;
1595}
1596
1597/* Push the scratch stack register on top of the stack. */
1598static inline void emit_push_r64(const u8 src[], u8 **pprog)
1599{
1600 u8 *prog = *pprog;
1601 int cnt = 0;
1602
1603 /* mov ecx,dword ptr [ebp+off] */
1604 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_ECX), STACK_VAR(src_hi));
1605 /* push ecx */
1606 EMIT1(0x51);
1607
1608 /* mov ecx,dword ptr [ebp+off] */
1609 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_ECX), STACK_VAR(src_lo));
1610 /* push ecx */
1611 EMIT1(0x51);
1612
1613 *pprog = prog;
1614}
1615
1616static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image,
1617 int oldproglen, struct jit_context *ctx)
1618{
1619 struct bpf_insn *insn = bpf_prog->insnsi;
1620 int insn_cnt = bpf_prog->len;
1621 bool seen_exit = false;
1622 u8 temp[BPF_MAX_INSN_SIZE + BPF_INSN_SAFETY];
1623 int i, cnt = 0;
1624 int proglen = 0;
1625 u8 *prog = temp;
1626
1627 emit_prologue(&prog, bpf_prog->aux->stack_depth);
1628
1629 for (i = 0; i < insn_cnt; i++, insn++) {
1630 const s32 imm32 = insn->imm;
1631 const bool is64 = BPF_CLASS(insn->code) == BPF_ALU64;
1632 const bool dstk = insn->dst_reg == BPF_REG_AX ? false : true;
1633 const bool sstk = insn->src_reg == BPF_REG_AX ? false : true;
1634 const u8 code = insn->code;
1635 const u8 *dst = bpf2ia32[insn->dst_reg];
1636 const u8 *src = bpf2ia32[insn->src_reg];
1637 const u8 *r0 = bpf2ia32[BPF_REG_0];
1638 s64 jmp_offset;
1639 u8 jmp_cond;
1640 int ilen;
1641 u8 *func;
1642
1643 switch (code) {
1644 /* ALU operations */
1645 /* dst = src */
1646 case BPF_ALU | BPF_MOV | BPF_K:
1647 case BPF_ALU | BPF_MOV | BPF_X:
1648 case BPF_ALU64 | BPF_MOV | BPF_K:
1649 case BPF_ALU64 | BPF_MOV | BPF_X:
1650 switch (BPF_SRC(code)) {
1651 case BPF_X:
1652 emit_ia32_mov_r64(is64, dst, src, dstk,
1653 sstk, &prog);
1654 break;
1655 case BPF_K:
1656 /* Sign-extend immediate value to dst reg */
1657 emit_ia32_mov_i64(is64, dst, imm32,
1658 dstk, &prog);
1659 break;
1660 }
1661 break;
1662 /* dst = dst + src/imm */
1663 /* dst = dst - src/imm */
1664 /* dst = dst | src/imm */
1665 /* dst = dst & src/imm */
1666 /* dst = dst ^ src/imm */
1667 /* dst = dst * src/imm */
1668 /* dst = dst << src */
1669 /* dst = dst >> src */
1670 case BPF_ALU | BPF_ADD | BPF_K:
1671 case BPF_ALU | BPF_ADD | BPF_X:
1672 case BPF_ALU | BPF_SUB | BPF_K:
1673 case BPF_ALU | BPF_SUB | BPF_X:
1674 case BPF_ALU | BPF_OR | BPF_K:
1675 case BPF_ALU | BPF_OR | BPF_X:
1676 case BPF_ALU | BPF_AND | BPF_K:
1677 case BPF_ALU | BPF_AND | BPF_X:
1678 case BPF_ALU | BPF_XOR | BPF_K:
1679 case BPF_ALU | BPF_XOR | BPF_X:
1680 case BPF_ALU64 | BPF_ADD | BPF_K:
1681 case BPF_ALU64 | BPF_ADD | BPF_X:
1682 case BPF_ALU64 | BPF_SUB | BPF_K:
1683 case BPF_ALU64 | BPF_SUB | BPF_X:
1684 case BPF_ALU64 | BPF_OR | BPF_K:
1685 case BPF_ALU64 | BPF_OR | BPF_X:
1686 case BPF_ALU64 | BPF_AND | BPF_K:
1687 case BPF_ALU64 | BPF_AND | BPF_X:
1688 case BPF_ALU64 | BPF_XOR | BPF_K:
1689 case BPF_ALU64 | BPF_XOR | BPF_X:
1690 switch (BPF_SRC(code)) {
1691 case BPF_X:
1692 emit_ia32_alu_r64(is64, BPF_OP(code), dst,
1693 src, dstk, sstk, &prog);
1694 break;
1695 case BPF_K:
1696 emit_ia32_alu_i64(is64, BPF_OP(code), dst,
1697 imm32, dstk, &prog);
1698 break;
1699 }
1700 break;
1701 case BPF_ALU | BPF_MUL | BPF_K:
1702 case BPF_ALU | BPF_MUL | BPF_X:
1703 switch (BPF_SRC(code)) {
1704 case BPF_X:
1705 emit_ia32_mul_r(dst_lo, src_lo, dstk,
1706 sstk, &prog);
1707 break;
1708 case BPF_K:
1709 /* mov ecx,imm32*/
1710 EMIT2_off32(0xC7, add_1reg(0xC0, IA32_ECX),
1711 imm32);
1712 emit_ia32_mul_r(dst_lo, IA32_ECX, dstk,
1713 false, &prog);
1714 break;
1715 }
1716 emit_ia32_mov_i(dst_hi, 0, dstk, &prog);
1717 break;
1718 case BPF_ALU | BPF_LSH | BPF_X:
1719 case BPF_ALU | BPF_RSH | BPF_X:
1720 case BPF_ALU | BPF_ARSH | BPF_K:
1721 case BPF_ALU | BPF_ARSH | BPF_X:
1722 switch (BPF_SRC(code)) {
1723 case BPF_X:
1724 emit_ia32_shift_r(BPF_OP(code), dst_lo, src_lo,
1725 dstk, sstk, &prog);
1726 break;
1727 case BPF_K:
1728 /* mov ecx,imm32*/
1729 EMIT2_off32(0xC7, add_1reg(0xC0, IA32_ECX),
1730 imm32);
1731 emit_ia32_shift_r(BPF_OP(code), dst_lo,
1732 IA32_ECX, dstk, false,
1733 &prog);
1734 break;
1735 }
1736 emit_ia32_mov_i(dst_hi, 0, dstk, &prog);
1737 break;
1738 /* dst = dst / src(imm) */
1739 /* dst = dst % src(imm) */
1740 case BPF_ALU | BPF_DIV | BPF_K:
1741 case BPF_ALU | BPF_DIV | BPF_X:
1742 case BPF_ALU | BPF_MOD | BPF_K:
1743 case BPF_ALU | BPF_MOD | BPF_X:
1744 switch (BPF_SRC(code)) {
1745 case BPF_X:
1746 emit_ia32_div_mod_r(BPF_OP(code), dst_lo,
1747 src_lo, dstk, sstk, &prog);
1748 break;
1749 case BPF_K:
1750 /* mov ecx,imm32*/
1751 EMIT2_off32(0xC7, add_1reg(0xC0, IA32_ECX),
1752 imm32);
1753 emit_ia32_div_mod_r(BPF_OP(code), dst_lo,
1754 IA32_ECX, dstk, false,
1755 &prog);
1756 break;
1757 }
1758 emit_ia32_mov_i(dst_hi, 0, dstk, &prog);
1759 break;
1760 case BPF_ALU64 | BPF_DIV | BPF_K:
1761 case BPF_ALU64 | BPF_DIV | BPF_X:
1762 case BPF_ALU64 | BPF_MOD | BPF_K:
1763 case BPF_ALU64 | BPF_MOD | BPF_X:
1764 goto notyet;
1765 /* dst = dst >> imm */
1766 /* dst = dst << imm */
1767 case BPF_ALU | BPF_RSH | BPF_K:
1768 case BPF_ALU | BPF_LSH | BPF_K:
1769 if (unlikely(imm32 > 31))
1770 return -EINVAL;
1771 /* mov ecx,imm32*/
1772 EMIT2_off32(0xC7, add_1reg(0xC0, IA32_ECX), imm32);
1773 emit_ia32_shift_r(BPF_OP(code), dst_lo, IA32_ECX, dstk,
1774 false, &prog);
1775 emit_ia32_mov_i(dst_hi, 0, dstk, &prog);
1776 break;
1777 /* dst = dst << imm */
1778 case BPF_ALU64 | BPF_LSH | BPF_K:
1779 if (unlikely(imm32 > 63))
1780 return -EINVAL;
1781 emit_ia32_lsh_i64(dst, imm32, dstk, &prog);
1782 break;
1783 /* dst = dst >> imm */
1784 case BPF_ALU64 | BPF_RSH | BPF_K:
1785 if (unlikely(imm32 > 63))
1786 return -EINVAL;
1787 emit_ia32_rsh_i64(dst, imm32, dstk, &prog);
1788 break;
1789 /* dst = dst << src */
1790 case BPF_ALU64 | BPF_LSH | BPF_X:
1791 emit_ia32_lsh_r64(dst, src, dstk, sstk, &prog);
1792 break;
1793 /* dst = dst >> src */
1794 case BPF_ALU64 | BPF_RSH | BPF_X:
1795 emit_ia32_rsh_r64(dst, src, dstk, sstk, &prog);
1796 break;
1797 /* dst = dst >> src (signed) */
1798 case BPF_ALU64 | BPF_ARSH | BPF_X:
1799 emit_ia32_arsh_r64(dst, src, dstk, sstk, &prog);
1800 break;
1801 /* dst = dst >> imm (signed) */
1802 case BPF_ALU64 | BPF_ARSH | BPF_K:
1803 if (unlikely(imm32 > 63))
1804 return -EINVAL;
1805 emit_ia32_arsh_i64(dst, imm32, dstk, &prog);
1806 break;
1807 /* dst = ~dst */
1808 case BPF_ALU | BPF_NEG:
1809 emit_ia32_alu_i(is64, false, BPF_OP(code),
1810 dst_lo, 0, dstk, &prog);
1811 emit_ia32_mov_i(dst_hi, 0, dstk, &prog);
1812 break;
1813 /* dst = ~dst (64 bit) */
1814 case BPF_ALU64 | BPF_NEG:
1815 emit_ia32_neg64(dst, dstk, &prog);
1816 break;
1817 /* dst = dst * src/imm */
1818 case BPF_ALU64 | BPF_MUL | BPF_X:
1819 case BPF_ALU64 | BPF_MUL | BPF_K:
1820 switch (BPF_SRC(code)) {
1821 case BPF_X:
1822 emit_ia32_mul_r64(dst, src, dstk, sstk, &prog);
1823 break;
1824 case BPF_K:
1825 emit_ia32_mul_i64(dst, imm32, dstk, &prog);
1826 break;
1827 }
1828 break;
1829 /* dst = htole(dst) */
1830 case BPF_ALU | BPF_END | BPF_FROM_LE:
1831 emit_ia32_to_le_r64(dst, imm32, dstk, &prog);
1832 break;
1833 /* dst = htobe(dst) */
1834 case BPF_ALU | BPF_END | BPF_FROM_BE:
1835 emit_ia32_to_be_r64(dst, imm32, dstk, &prog);
1836 break;
1837 /* dst = imm64 */
1838 case BPF_LD | BPF_IMM | BPF_DW: {
1839 s32 hi, lo = imm32;
1840
1841 hi = insn[1].imm;
1842 emit_ia32_mov_i(dst_lo, lo, dstk, &prog);
1843 emit_ia32_mov_i(dst_hi, hi, dstk, &prog);
1844 insn++;
1845 i++;
1846 break;
1847 }
1848 /* ST: *(u8*)(dst_reg + off) = imm */
1849 case BPF_ST | BPF_MEM | BPF_H:
1850 case BPF_ST | BPF_MEM | BPF_B:
1851 case BPF_ST | BPF_MEM | BPF_W:
1852 case BPF_ST | BPF_MEM | BPF_DW:
1853 if (dstk)
1854 /* mov eax,dword ptr [ebp+off] */
1855 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
1856 STACK_VAR(dst_lo));
1857 else
1858 /* mov eax,dst_lo */
1859 EMIT2(0x8B, add_2reg(0xC0, dst_lo, IA32_EAX));
1860
1861 switch (BPF_SIZE(code)) {
1862 case BPF_B:
1863 EMIT(0xC6, 1); break;
1864 case BPF_H:
1865 EMIT2(0x66, 0xC7); break;
1866 case BPF_W:
1867 case BPF_DW:
1868 EMIT(0xC7, 1); break;
1869 }
1870
1871 if (is_imm8(insn->off))
1872 EMIT2(add_1reg(0x40, IA32_EAX), insn->off);
1873 else
1874 EMIT1_off32(add_1reg(0x80, IA32_EAX),
1875 insn->off);
1876 EMIT(imm32, bpf_size_to_x86_bytes(BPF_SIZE(code)));
1877
1878 if (BPF_SIZE(code) == BPF_DW) {
1879 u32 hi;
1880
1881 hi = imm32 & (1<<31) ? (u32)~0 : 0;
1882 EMIT2_off32(0xC7, add_1reg(0x80, IA32_EAX),
1883 insn->off + 4);
1884 EMIT(hi, 4);
1885 }
1886 break;
1887
1888 /* STX: *(u8*)(dst_reg + off) = src_reg */
1889 case BPF_STX | BPF_MEM | BPF_B:
1890 case BPF_STX | BPF_MEM | BPF_H:
1891 case BPF_STX | BPF_MEM | BPF_W:
1892 case BPF_STX | BPF_MEM | BPF_DW:
1893 if (dstk)
1894 /* mov eax,dword ptr [ebp+off] */
1895 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
1896 STACK_VAR(dst_lo));
1897 else
1898 /* mov eax,dst_lo */
1899 EMIT2(0x8B, add_2reg(0xC0, dst_lo, IA32_EAX));
1900
1901 if (sstk)
1902 /* mov edx,dword ptr [ebp+off] */
1903 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
1904 STACK_VAR(src_lo));
1905 else
1906 /* mov edx,src_lo */
1907 EMIT2(0x8B, add_2reg(0xC0, src_lo, IA32_EDX));
1908
1909 switch (BPF_SIZE(code)) {
1910 case BPF_B:
1911 EMIT(0x88, 1); break;
1912 case BPF_H:
1913 EMIT2(0x66, 0x89); break;
1914 case BPF_W:
1915 case BPF_DW:
1916 EMIT(0x89, 1); break;
1917 }
1918
1919 if (is_imm8(insn->off))
1920 EMIT2(add_2reg(0x40, IA32_EAX, IA32_EDX),
1921 insn->off);
1922 else
1923 EMIT1_off32(add_2reg(0x80, IA32_EAX, IA32_EDX),
1924 insn->off);
1925
1926 if (BPF_SIZE(code) == BPF_DW) {
1927 if (sstk)
1928 /* mov edi,dword ptr [ebp+off] */
1929 EMIT3(0x8B, add_2reg(0x40, IA32_EBP,
1930 IA32_EDX),
1931 STACK_VAR(src_hi));
1932 else
1933 /* mov edi,src_hi */
1934 EMIT2(0x8B, add_2reg(0xC0, src_hi,
1935 IA32_EDX));
1936 EMIT1(0x89);
1937 if (is_imm8(insn->off + 4)) {
1938 EMIT2(add_2reg(0x40, IA32_EAX,
1939 IA32_EDX),
1940 insn->off + 4);
1941 } else {
1942 EMIT1(add_2reg(0x80, IA32_EAX,
1943 IA32_EDX));
1944 EMIT(insn->off + 4, 4);
1945 }
1946 }
1947 break;
1948
1949 /* LDX: dst_reg = *(u8*)(src_reg + off) */
1950 case BPF_LDX | BPF_MEM | BPF_B:
1951 case BPF_LDX | BPF_MEM | BPF_H:
1952 case BPF_LDX | BPF_MEM | BPF_W:
1953 case BPF_LDX | BPF_MEM | BPF_DW:
1954 if (sstk)
1955 /* mov eax,dword ptr [ebp+off] */
1956 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
1957 STACK_VAR(src_lo));
1958 else
1959 /* mov eax,dword ptr [ebp+off] */
1960 EMIT2(0x8B, add_2reg(0xC0, src_lo, IA32_EAX));
1961
1962 switch (BPF_SIZE(code)) {
1963 case BPF_B:
1964 EMIT2(0x0F, 0xB6); break;
1965 case BPF_H:
1966 EMIT2(0x0F, 0xB7); break;
1967 case BPF_W:
1968 case BPF_DW:
1969 EMIT(0x8B, 1); break;
1970 }
1971
1972 if (is_imm8(insn->off))
1973 EMIT2(add_2reg(0x40, IA32_EAX, IA32_EDX),
1974 insn->off);
1975 else
1976 EMIT1_off32(add_2reg(0x80, IA32_EAX, IA32_EDX),
1977 insn->off);
1978
1979 if (dstk)
1980 /* mov dword ptr [ebp+off],edx */
1981 EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EDX),
1982 STACK_VAR(dst_lo));
1983 else
1984 /* mov dst_lo,edx */
1985 EMIT2(0x89, add_2reg(0xC0, dst_lo, IA32_EDX));
1986 switch (BPF_SIZE(code)) {
1987 case BPF_B:
1988 case BPF_H:
1989 case BPF_W:
1990 if (dstk) {
1991 EMIT3(0xC7, add_1reg(0x40, IA32_EBP),
1992 STACK_VAR(dst_hi));
1993 EMIT(0x0, 4);
1994 } else {
1995 EMIT3(0xC7, add_1reg(0xC0, dst_hi), 0);
1996 }
1997 break;
1998 case BPF_DW:
1999 EMIT2_off32(0x8B,
2000 add_2reg(0x80, IA32_EAX, IA32_EDX),
2001 insn->off + 4);
2002 if (dstk)
2003 EMIT3(0x89,
2004 add_2reg(0x40, IA32_EBP,
2005 IA32_EDX),
2006 STACK_VAR(dst_hi));
2007 else
2008 EMIT2(0x89,
2009 add_2reg(0xC0, dst_hi, IA32_EDX));
2010 break;
2011 default:
2012 break;
2013 }
2014 break;
2015 /* call */
2016 case BPF_JMP | BPF_CALL:
2017 {
2018 const u8 *r1 = bpf2ia32[BPF_REG_1];
2019 const u8 *r2 = bpf2ia32[BPF_REG_2];
2020 const u8 *r3 = bpf2ia32[BPF_REG_3];
2021 const u8 *r4 = bpf2ia32[BPF_REG_4];
2022 const u8 *r5 = bpf2ia32[BPF_REG_5];
2023
2024 if (insn->src_reg == BPF_PSEUDO_CALL)
2025 goto notyet;
2026
2027 func = (u8 *) __bpf_call_base + imm32;
2028 jmp_offset = func - (image + addrs[i]);
2029
2030 if (!imm32 || !is_simm32(jmp_offset)) {
2031 pr_err("unsupported BPF func %d addr %p image %p\n",
2032 imm32, func, image);
2033 return -EINVAL;
2034 }
2035
2036 /* mov eax,dword ptr [ebp+off] */
2037 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
2038 STACK_VAR(r1[0]));
2039 /* mov edx,dword ptr [ebp+off] */
2040 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
2041 STACK_VAR(r1[1]));
2042
2043 emit_push_r64(r5, &prog);
2044 emit_push_r64(r4, &prog);
2045 emit_push_r64(r3, &prog);
2046 emit_push_r64(r2, &prog);
2047
2048 EMIT1_off32(0xE8, jmp_offset + 9);
2049
2050 /* mov dword ptr [ebp+off],eax */
2051 EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EAX),
2052 STACK_VAR(r0[0]));
2053 /* mov dword ptr [ebp+off],edx */
2054 EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EDX),
2055 STACK_VAR(r0[1]));
2056
2057 /* add esp,32 */
2058 EMIT3(0x83, add_1reg(0xC0, IA32_ESP), 32);
2059 break;
2060 }
2061 case BPF_JMP | BPF_TAIL_CALL:
2062 emit_bpf_tail_call(&prog);
2063 break;
2064
2065 /* cond jump */
2066 case BPF_JMP | BPF_JEQ | BPF_X:
2067 case BPF_JMP | BPF_JNE | BPF_X:
2068 case BPF_JMP | BPF_JGT | BPF_X:
2069 case BPF_JMP | BPF_JLT | BPF_X:
2070 case BPF_JMP | BPF_JGE | BPF_X:
2071 case BPF_JMP | BPF_JLE | BPF_X:
2072 case BPF_JMP | BPF_JSGT | BPF_X:
2073 case BPF_JMP | BPF_JSLE | BPF_X:
2074 case BPF_JMP | BPF_JSLT | BPF_X:
2075 case BPF_JMP | BPF_JSGE | BPF_X: {
2076 u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
2077 u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
2078 u8 sreg_lo = sstk ? IA32_ECX : src_lo;
2079 u8 sreg_hi = sstk ? IA32_EBX : src_hi;
2080
2081 if (dstk) {
2082 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
2083 STACK_VAR(dst_lo));
2084 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
2085 STACK_VAR(dst_hi));
2086 }
2087
2088 if (sstk) {
2089 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_ECX),
2090 STACK_VAR(src_lo));
2091 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EBX),
2092 STACK_VAR(src_hi));
2093 }
2094
2095 /* cmp dreg_hi,sreg_hi */
2096 EMIT2(0x39, add_2reg(0xC0, dreg_hi, sreg_hi));
2097 EMIT2(IA32_JNE, 2);
2098 /* cmp dreg_lo,sreg_lo */
2099 EMIT2(0x39, add_2reg(0xC0, dreg_lo, sreg_lo));
2100 goto emit_cond_jmp;
2101 }
2102 case BPF_JMP | BPF_JSET | BPF_X: {
2103 u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
2104 u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
2105 u8 sreg_lo = sstk ? IA32_ECX : src_lo;
2106 u8 sreg_hi = sstk ? IA32_EBX : src_hi;
2107
2108 if (dstk) {
2109 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
2110 STACK_VAR(dst_lo));
2111 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
2112 STACK_VAR(dst_hi));
2113 }
2114
2115 if (sstk) {
2116 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_ECX),
2117 STACK_VAR(src_lo));
2118 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EBX),
2119 STACK_VAR(src_hi));
2120 }
2121 /* and dreg_lo,sreg_lo */
2122 EMIT2(0x23, add_2reg(0xC0, sreg_lo, dreg_lo));
2123 /* and dreg_hi,sreg_hi */
2124 EMIT2(0x23, add_2reg(0xC0, sreg_hi, dreg_hi));
2125 /* or dreg_lo,dreg_hi */
2126 EMIT2(0x09, add_2reg(0xC0, dreg_lo, dreg_hi));
2127 goto emit_cond_jmp;
2128 }
2129 case BPF_JMP | BPF_JSET | BPF_K: {
2130 u32 hi;
2131 u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
2132 u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
2133 u8 sreg_lo = IA32_ECX;
2134 u8 sreg_hi = IA32_EBX;
2135
2136 if (dstk) {
2137 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
2138 STACK_VAR(dst_lo));
2139 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
2140 STACK_VAR(dst_hi));
2141 }
2142 hi = imm32 & (1<<31) ? (u32)~0 : 0;
2143
2144 /* mov ecx,imm32 */
2145 EMIT2_off32(0xC7, add_1reg(0xC0, IA32_ECX), imm32);
2146 /* mov ebx,imm32 */
2147 EMIT2_off32(0xC7, add_1reg(0xC0, IA32_EBX), hi);
2148
2149 /* and dreg_lo,sreg_lo */
2150 EMIT2(0x23, add_2reg(0xC0, sreg_lo, dreg_lo));
2151 /* and dreg_hi,sreg_hi */
2152 EMIT2(0x23, add_2reg(0xC0, sreg_hi, dreg_hi));
2153 /* or dreg_lo,dreg_hi */
2154 EMIT2(0x09, add_2reg(0xC0, dreg_lo, dreg_hi));
2155 goto emit_cond_jmp;
2156 }
2157 case BPF_JMP | BPF_JEQ | BPF_K:
2158 case BPF_JMP | BPF_JNE | BPF_K:
2159 case BPF_JMP | BPF_JGT | BPF_K:
2160 case BPF_JMP | BPF_JLT | BPF_K:
2161 case BPF_JMP | BPF_JGE | BPF_K:
2162 case BPF_JMP | BPF_JLE | BPF_K:
2163 case BPF_JMP | BPF_JSGT | BPF_K:
2164 case BPF_JMP | BPF_JSLE | BPF_K:
2165 case BPF_JMP | BPF_JSLT | BPF_K:
2166 case BPF_JMP | BPF_JSGE | BPF_K: {
2167 u32 hi;
2168 u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
2169 u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
2170 u8 sreg_lo = IA32_ECX;
2171 u8 sreg_hi = IA32_EBX;
2172
2173 if (dstk) {
2174 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
2175 STACK_VAR(dst_lo));
2176 EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
2177 STACK_VAR(dst_hi));
2178 }
2179
2180 hi = imm32 & (1<<31) ? (u32)~0 : 0;
2181 /* mov ecx,imm32 */
2182 EMIT2_off32(0xC7, add_1reg(0xC0, IA32_ECX), imm32);
2183 /* mov ebx,imm32 */
2184 EMIT2_off32(0xC7, add_1reg(0xC0, IA32_EBX), hi);
2185
2186 /* cmp dreg_hi,sreg_hi */
2187 EMIT2(0x39, add_2reg(0xC0, dreg_hi, sreg_hi));
2188 EMIT2(IA32_JNE, 2);
2189 /* cmp dreg_lo,sreg_lo */
2190 EMIT2(0x39, add_2reg(0xC0, dreg_lo, sreg_lo));
2191
2192emit_cond_jmp: /* Convert BPF opcode to x86 */
2193 switch (BPF_OP(code)) {
2194 case BPF_JEQ:
2195 jmp_cond = IA32_JE;
2196 break;
2197 case BPF_JSET:
2198 case BPF_JNE:
2199 jmp_cond = IA32_JNE;
2200 break;
2201 case BPF_JGT:
2202 /* GT is unsigned '>', JA in x86 */
2203 jmp_cond = IA32_JA;
2204 break;
2205 case BPF_JLT:
2206 /* LT is unsigned '<', JB in x86 */
2207 jmp_cond = IA32_JB;
2208 break;
2209 case BPF_JGE:
2210 /* GE is unsigned '>=', JAE in x86 */
2211 jmp_cond = IA32_JAE;
2212 break;
2213 case BPF_JLE:
2214 /* LE is unsigned '<=', JBE in x86 */
2215 jmp_cond = IA32_JBE;
2216 break;
2217 case BPF_JSGT:
2218 /* Signed '>', GT in x86 */
2219 jmp_cond = IA32_JG;
2220 break;
2221 case BPF_JSLT:
2222 /* Signed '<', LT in x86 */
2223 jmp_cond = IA32_JL;
2224 break;
2225 case BPF_JSGE:
2226 /* Signed '>=', GE in x86 */
2227 jmp_cond = IA32_JGE;
2228 break;
2229 case BPF_JSLE:
2230 /* Signed '<=', LE in x86 */
2231 jmp_cond = IA32_JLE;
2232 break;
2233 default: /* to silence GCC warning */
2234 return -EFAULT;
2235 }
2236 jmp_offset = addrs[i + insn->off] - addrs[i];
2237 if (is_imm8(jmp_offset)) {
2238 EMIT2(jmp_cond, jmp_offset);
2239 } else if (is_simm32(jmp_offset)) {
2240 EMIT2_off32(0x0F, jmp_cond + 0x10, jmp_offset);
2241 } else {
2242 pr_err("cond_jmp gen bug %llx\n", jmp_offset);
2243 return -EFAULT;
2244 }
2245
2246 break;
2247 }
2248 case BPF_JMP | BPF_JA:
2249 if (insn->off == -1)
2250 /* -1 jmp instructions will always jump
2251 * backwards two bytes. Explicitly handling
2252 * this case avoids wasting too many passes
2253 * when there are long sequences of replaced
2254 * dead code.
2255 */
2256 jmp_offset = -2;
2257 else
2258 jmp_offset = addrs[i + insn->off] - addrs[i];
2259
2260 if (!jmp_offset)
2261 /* Optimize out nop jumps */
2262 break;
2263emit_jmp:
2264 if (is_imm8(jmp_offset)) {
2265 EMIT2(0xEB, jmp_offset);
2266 } else if (is_simm32(jmp_offset)) {
2267 EMIT1_off32(0xE9, jmp_offset);
2268 } else {
2269 pr_err("jmp gen bug %llx\n", jmp_offset);
2270 return -EFAULT;
2271 }
2272 break;
2273 /* STX XADD: lock *(u32 *)(dst + off) += src */
2274 case BPF_STX | BPF_XADD | BPF_W:
2275 /* STX XADD: lock *(u64 *)(dst + off) += src */
2276 case BPF_STX | BPF_XADD | BPF_DW:
2277 goto notyet;
2278 case BPF_JMP | BPF_EXIT:
2279 if (seen_exit) {
2280 jmp_offset = ctx->cleanup_addr - addrs[i];
2281 goto emit_jmp;
2282 }
2283 seen_exit = true;
2284 /* Update cleanup_addr */
2285 ctx->cleanup_addr = proglen;
2286 emit_epilogue(&prog, bpf_prog->aux->stack_depth);
2287 break;
2288notyet:
2289 pr_info_once("*** NOT YET: opcode %02x ***\n", code);
2290 return -EFAULT;
2291 default:
2292 /*
2293 * This error will be seen if new instruction was added
2294 * to interpreter, but not to JIT or if there is junk in
2295 * bpf_prog
2296 */
2297 pr_err("bpf_jit: unknown opcode %02x\n", code);
2298 return -EINVAL;
2299 }
2300
2301 ilen = prog - temp;
2302 if (ilen > BPF_MAX_INSN_SIZE) {
2303 pr_err("bpf_jit: fatal insn size error\n");
2304 return -EFAULT;
2305 }
2306
2307 if (image) {
2308 if (unlikely(proglen + ilen > oldproglen)) {
2309 pr_err("bpf_jit: fatal error\n");
2310 return -EFAULT;
2311 }
2312 memcpy(image + proglen, temp, ilen);
2313 }
2314 proglen += ilen;
2315 addrs[i] = proglen;
2316 prog = temp;
2317 }
2318 return proglen;
2319}
2320
2321struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
2322{
2323 struct bpf_binary_header *header = NULL;
2324 struct bpf_prog *tmp, *orig_prog = prog;
2325 int proglen, oldproglen = 0;
2326 struct jit_context ctx = {};
2327 bool tmp_blinded = false;
2328 u8 *image = NULL;
2329 int *addrs;
2330 int pass;
2331 int i;
2332
2333 if (!prog->jit_requested)
2334 return orig_prog;
2335
2336 tmp = bpf_jit_blind_constants(prog);
2337 /*
2338 * If blinding was requested and we failed during blinding,
2339 * we must fall back to the interpreter.
2340 */
2341 if (IS_ERR(tmp))
2342 return orig_prog;
2343 if (tmp != prog) {
2344 tmp_blinded = true;
2345 prog = tmp;
2346 }
2347
2348 addrs = kmalloc(prog->len * sizeof(*addrs), GFP_KERNEL);
2349 if (!addrs) {
2350 prog = orig_prog;
2351 goto out;
2352 }
2353
2354 /*
2355 * Before first pass, make a rough estimation of addrs[]
2356 * each BPF instruction is translated to less than 64 bytes
2357 */
2358 for (proglen = 0, i = 0; i < prog->len; i++) {
2359 proglen += 64;
2360 addrs[i] = proglen;
2361 }
2362 ctx.cleanup_addr = proglen;
2363
2364 /*
2365 * JITed image shrinks with every pass and the loop iterates
2366 * until the image stops shrinking. Very large BPF programs
2367 * may converge on the last pass. In such case do one more
2368 * pass to emit the final image.
2369 */
2370 for (pass = 0; pass < 20 || image; pass++) {
2371 proglen = do_jit(prog, addrs, image, oldproglen, &ctx);
2372 if (proglen <= 0) {
2373out_image:
2374 image = NULL;
2375 if (header)
2376 bpf_jit_binary_free(header);
2377 prog = orig_prog;
2378 goto out_addrs;
2379 }
2380 if (image) {
2381 if (proglen != oldproglen) {
2382 pr_err("bpf_jit: proglen=%d != oldproglen=%d\n",
2383 proglen, oldproglen);
2384 goto out_image;
2385 }
2386 break;
2387 }
2388 if (proglen == oldproglen) {
2389 header = bpf_jit_binary_alloc(proglen, &image,
2390 1, jit_fill_hole);
2391 if (!header) {
2392 prog = orig_prog;
2393 goto out_addrs;
2394 }
2395 }
2396 oldproglen = proglen;
2397 cond_resched();
2398 }
2399
2400 if (bpf_jit_enable > 1)
2401 bpf_jit_dump(prog->len, proglen, pass + 1, image);
2402
2403 if (image) {
2404 bpf_jit_binary_lock_ro(header);
2405 prog->bpf_func = (void *)image;
2406 prog->jited = 1;
2407 prog->jited_len = proglen;
2408 } else {
2409 prog = orig_prog;
2410 }
2411
2412out_addrs:
2413 kfree(addrs);
2414out:
2415 if (tmp_blinded)
2416 bpf_jit_prog_release_other(prog, prog == orig_prog ?
2417 tmp : orig_prog);
2418 return prog;
2419}
generated by cgit v1.2.2 (git 2.25.0) at 2026-01-04 16:58:11 -0500