10a14842fSEric Dumazet /* bpf_jit_comp.c : BPF JIT compiler 20a14842fSEric Dumazet * 33b58908aSEric Dumazet * Copyright (C) 2011-2013 Eric Dumazet (eric.dumazet@gmail.com) 462258278SAlexei Starovoitov * Internal BPF Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com 50a14842fSEric Dumazet * 60a14842fSEric Dumazet * This program is free software; you can redistribute it and/or 70a14842fSEric Dumazet * modify it under the terms of the GNU General Public License 80a14842fSEric Dumazet * as published by the Free Software Foundation; version 2 90a14842fSEric Dumazet * of the License. 100a14842fSEric Dumazet */ 110a14842fSEric Dumazet #include <linux/netdevice.h> 120a14842fSEric Dumazet #include <linux/filter.h> 13855ddb56SEric Dumazet #include <linux/if_vlan.h> 14738cbe72SDaniel Borkmann #include <asm/cacheflush.h> 15d1163651SLaura Abbott #include <asm/set_memory.h> 16b52f00e6SAlexei Starovoitov #include <linux/bpf.h> 170a14842fSEric Dumazet 180a14842fSEric Dumazet /* 190a14842fSEric Dumazet * assembly code in arch/x86/net/bpf_jit.S 200a14842fSEric Dumazet */ 2162258278SAlexei Starovoitov extern u8 sk_load_word[], sk_load_half[], sk_load_byte[]; 22a998d434SJan Seiffert extern u8 sk_load_word_positive_offset[], sk_load_half_positive_offset[]; 2362258278SAlexei Starovoitov extern u8 sk_load_byte_positive_offset[]; 24a998d434SJan Seiffert extern u8 sk_load_word_negative_offset[], sk_load_half_negative_offset[]; 2562258278SAlexei Starovoitov extern u8 sk_load_byte_negative_offset[]; 260a14842fSEric Dumazet 275cccc702SJoe Perches static u8 *emit_code(u8 *ptr, u32 bytes, unsigned int len) 280a14842fSEric Dumazet { 290a14842fSEric Dumazet if (len == 1) 300a14842fSEric Dumazet *ptr = bytes; 310a14842fSEric Dumazet else if (len == 2) 320a14842fSEric Dumazet *(u16 *)ptr = bytes; 330a14842fSEric Dumazet else { 340a14842fSEric Dumazet *(u32 *)ptr = bytes; 350a14842fSEric Dumazet barrier(); 360a14842fSEric Dumazet } 370a14842fSEric Dumazet return ptr + len; 380a14842fSEric Dumazet } 390a14842fSEric Dumazet 40b52f00e6SAlexei Starovoitov #define EMIT(bytes, len) \ 41b52f00e6SAlexei Starovoitov do { prog = emit_code(prog, bytes, len); cnt += len; } while (0) 420a14842fSEric Dumazet 430a14842fSEric Dumazet #define EMIT1(b1) EMIT(b1, 1) 440a14842fSEric Dumazet #define EMIT2(b1, b2) EMIT((b1) + ((b2) << 8), 2) 450a14842fSEric Dumazet #define EMIT3(b1, b2, b3) EMIT((b1) + ((b2) << 8) + ((b3) << 16), 3) 460a14842fSEric Dumazet #define EMIT4(b1, b2, b3, b4) EMIT((b1) + ((b2) << 8) + ((b3) << 16) + ((b4) << 24), 4) 4762258278SAlexei Starovoitov #define EMIT1_off32(b1, off) \ 4862258278SAlexei Starovoitov do {EMIT1(b1); EMIT(off, 4); } while (0) 4962258278SAlexei Starovoitov #define EMIT2_off32(b1, b2, off) \ 5062258278SAlexei Starovoitov do {EMIT2(b1, b2); EMIT(off, 4); } while (0) 5162258278SAlexei Starovoitov #define EMIT3_off32(b1, b2, b3, off) \ 5262258278SAlexei Starovoitov do {EMIT3(b1, b2, b3); EMIT(off, 4); } while (0) 5362258278SAlexei Starovoitov #define EMIT4_off32(b1, b2, b3, b4, off) \ 5462258278SAlexei Starovoitov do {EMIT4(b1, b2, b3, b4); EMIT(off, 4); } while (0) 550a14842fSEric Dumazet 565cccc702SJoe Perches static bool is_imm8(int value) 570a14842fSEric Dumazet { 580a14842fSEric Dumazet return value <= 127 && value >= -128; 590a14842fSEric Dumazet } 600a14842fSEric Dumazet 615cccc702SJoe Perches static bool is_simm32(s64 value) 620a14842fSEric Dumazet { 6362258278SAlexei Starovoitov return value == (s64) (s32) value; 640a14842fSEric Dumazet } 650a14842fSEric Dumazet 66e430f34eSAlexei Starovoitov /* mov dst, src */ 67e430f34eSAlexei Starovoitov #define EMIT_mov(DST, SRC) \ 68e430f34eSAlexei Starovoitov do {if (DST != SRC) \ 69e430f34eSAlexei Starovoitov EMIT3(add_2mod(0x48, DST, SRC), 0x89, add_2reg(0xC0, DST, SRC)); \ 700a14842fSEric Dumazet } while (0) 710a14842fSEric Dumazet 7262258278SAlexei Starovoitov static int bpf_size_to_x86_bytes(int bpf_size) 7362258278SAlexei Starovoitov { 7462258278SAlexei Starovoitov if (bpf_size == BPF_W) 7562258278SAlexei Starovoitov return 4; 7662258278SAlexei Starovoitov else if (bpf_size == BPF_H) 7762258278SAlexei Starovoitov return 2; 7862258278SAlexei Starovoitov else if (bpf_size == BPF_B) 7962258278SAlexei Starovoitov return 1; 8062258278SAlexei Starovoitov else if (bpf_size == BPF_DW) 8162258278SAlexei Starovoitov return 4; /* imm32 */ 8262258278SAlexei Starovoitov else 8362258278SAlexei Starovoitov return 0; 8462258278SAlexei Starovoitov } 8562258278SAlexei Starovoitov 860a14842fSEric Dumazet /* list of x86 cond jumps opcodes (. + s8) 870a14842fSEric Dumazet * Add 0x10 (and an extra 0x0f) to generate far jumps (. + s32) 880a14842fSEric Dumazet */ 890a14842fSEric Dumazet #define X86_JB 0x72 900a14842fSEric Dumazet #define X86_JAE 0x73 910a14842fSEric Dumazet #define X86_JE 0x74 920a14842fSEric Dumazet #define X86_JNE 0x75 930a14842fSEric Dumazet #define X86_JBE 0x76 940a14842fSEric Dumazet #define X86_JA 0x77 9552afc51eSDaniel Borkmann #define X86_JL 0x7C 9662258278SAlexei Starovoitov #define X86_JGE 0x7D 9752afc51eSDaniel Borkmann #define X86_JLE 0x7E 9862258278SAlexei Starovoitov #define X86_JG 0x7F 990a14842fSEric Dumazet 1005cccc702SJoe Perches static void bpf_flush_icache(void *start, void *end) 1010a14842fSEric Dumazet { 1020a14842fSEric Dumazet mm_segment_t old_fs = get_fs(); 1030a14842fSEric Dumazet 1040a14842fSEric Dumazet set_fs(KERNEL_DS); 1050a14842fSEric Dumazet smp_wmb(); 1060a14842fSEric Dumazet flush_icache_range((unsigned long)start, (unsigned long)end); 1070a14842fSEric Dumazet set_fs(old_fs); 1080a14842fSEric Dumazet } 1090a14842fSEric Dumazet 110a998d434SJan Seiffert #define CHOOSE_LOAD_FUNC(K, func) \ 111a998d434SJan Seiffert ((int)K < 0 ? ((int)K >= SKF_LL_OFF ? func##_negative_offset : func) : func##_positive_offset) 1120a14842fSEric Dumazet 11362258278SAlexei Starovoitov /* pick a register outside of BPF range for JIT internal work */ 114959a7579SDaniel Borkmann #define AUX_REG (MAX_BPF_JIT_REG + 1) 11562258278SAlexei Starovoitov 116959a7579SDaniel Borkmann /* The following table maps BPF registers to x64 registers. 117959a7579SDaniel Borkmann * 118959a7579SDaniel Borkmann * x64 register r12 is unused, since if used as base address 119959a7579SDaniel Borkmann * register in load/store instructions, it always needs an 120959a7579SDaniel Borkmann * extra byte of encoding and is callee saved. 121959a7579SDaniel Borkmann * 122959a7579SDaniel Borkmann * r9 caches skb->len - skb->data_len 123959a7579SDaniel Borkmann * r10 caches skb->data, and used for blinding (if enabled) 12462258278SAlexei Starovoitov */ 12562258278SAlexei Starovoitov static const int reg2hex[] = { 12662258278SAlexei Starovoitov [BPF_REG_0] = 0, /* rax */ 12762258278SAlexei Starovoitov [BPF_REG_1] = 7, /* rdi */ 12862258278SAlexei Starovoitov [BPF_REG_2] = 6, /* rsi */ 12962258278SAlexei Starovoitov [BPF_REG_3] = 2, /* rdx */ 13062258278SAlexei Starovoitov [BPF_REG_4] = 1, /* rcx */ 13162258278SAlexei Starovoitov [BPF_REG_5] = 0, /* r8 */ 13262258278SAlexei Starovoitov [BPF_REG_6] = 3, /* rbx callee saved */ 13362258278SAlexei Starovoitov [BPF_REG_7] = 5, /* r13 callee saved */ 13462258278SAlexei Starovoitov [BPF_REG_8] = 6, /* r14 callee saved */ 13562258278SAlexei Starovoitov [BPF_REG_9] = 7, /* r15 callee saved */ 13662258278SAlexei Starovoitov [BPF_REG_FP] = 5, /* rbp readonly */ 137959a7579SDaniel Borkmann [BPF_REG_AX] = 2, /* r10 temp register */ 13862258278SAlexei Starovoitov [AUX_REG] = 3, /* r11 temp register */ 13962258278SAlexei Starovoitov }; 14062258278SAlexei Starovoitov 14162258278SAlexei Starovoitov /* is_ereg() == true if BPF register 'reg' maps to x64 r8..r15 14262258278SAlexei Starovoitov * which need extra byte of encoding. 14362258278SAlexei Starovoitov * rax,rcx,...,rbp have simpler encoding 14462258278SAlexei Starovoitov */ 1455cccc702SJoe Perches static bool is_ereg(u32 reg) 14662258278SAlexei Starovoitov { 147d148134bSJoe Perches return (1 << reg) & (BIT(BPF_REG_5) | 148d148134bSJoe Perches BIT(AUX_REG) | 149d148134bSJoe Perches BIT(BPF_REG_7) | 150d148134bSJoe Perches BIT(BPF_REG_8) | 151959a7579SDaniel Borkmann BIT(BPF_REG_9) | 152959a7579SDaniel Borkmann BIT(BPF_REG_AX)); 15362258278SAlexei Starovoitov } 15462258278SAlexei Starovoitov 155de0a444dSDaniel Borkmann static bool is_axreg(u32 reg) 156de0a444dSDaniel Borkmann { 157de0a444dSDaniel Borkmann return reg == BPF_REG_0; 158de0a444dSDaniel Borkmann } 159de0a444dSDaniel Borkmann 16062258278SAlexei Starovoitov /* add modifiers if 'reg' maps to x64 registers r8..r15 */ 1615cccc702SJoe Perches static u8 add_1mod(u8 byte, u32 reg) 16262258278SAlexei Starovoitov { 16362258278SAlexei Starovoitov if (is_ereg(reg)) 16462258278SAlexei Starovoitov byte |= 1; 16562258278SAlexei Starovoitov return byte; 16662258278SAlexei Starovoitov } 16762258278SAlexei Starovoitov 1685cccc702SJoe Perches static u8 add_2mod(u8 byte, u32 r1, u32 r2) 16962258278SAlexei Starovoitov { 17062258278SAlexei Starovoitov if (is_ereg(r1)) 17162258278SAlexei Starovoitov byte |= 1; 17262258278SAlexei Starovoitov if (is_ereg(r2)) 17362258278SAlexei Starovoitov byte |= 4; 17462258278SAlexei Starovoitov return byte; 17562258278SAlexei Starovoitov } 17662258278SAlexei Starovoitov 177e430f34eSAlexei Starovoitov /* encode 'dst_reg' register into x64 opcode 'byte' */ 1785cccc702SJoe Perches static u8 add_1reg(u8 byte, u32 dst_reg) 17962258278SAlexei Starovoitov { 180e430f34eSAlexei Starovoitov return byte + reg2hex[dst_reg]; 18162258278SAlexei Starovoitov } 18262258278SAlexei Starovoitov 183e430f34eSAlexei Starovoitov /* encode 'dst_reg' and 'src_reg' registers into x64 opcode 'byte' */ 1845cccc702SJoe Perches static u8 add_2reg(u8 byte, u32 dst_reg, u32 src_reg) 18562258278SAlexei Starovoitov { 186e430f34eSAlexei Starovoitov return byte + reg2hex[dst_reg] + (reg2hex[src_reg] << 3); 18762258278SAlexei Starovoitov } 18862258278SAlexei Starovoitov 189738cbe72SDaniel Borkmann static void jit_fill_hole(void *area, unsigned int size) 190738cbe72SDaniel Borkmann { 191738cbe72SDaniel Borkmann /* fill whole space with int3 instructions */ 192738cbe72SDaniel Borkmann memset(area, 0xcc, size); 193738cbe72SDaniel Borkmann } 194738cbe72SDaniel Borkmann 195f3c2af7bSAlexei Starovoitov struct jit_context { 196769e0de6SAlexei Starovoitov int cleanup_addr; /* epilogue code offset */ 19762258278SAlexei Starovoitov bool seen_ld_abs; 198959a7579SDaniel Borkmann bool seen_ax_reg; 199f3c2af7bSAlexei Starovoitov }; 200f3c2af7bSAlexei Starovoitov 201e0ee9c12SAlexei Starovoitov /* maximum number of bytes emitted while JITing one eBPF insn */ 202e0ee9c12SAlexei Starovoitov #define BPF_MAX_INSN_SIZE 128 203e0ee9c12SAlexei Starovoitov #define BPF_INSN_SAFETY 64 204e0ee9c12SAlexei Starovoitov 205177366bfSAlexei Starovoitov #define AUX_STACK_SPACE \ 206177366bfSAlexei Starovoitov (32 /* space for rbx, r13, r14, r15 */ + \ 207b52f00e6SAlexei Starovoitov 8 /* space for skb_copy_bits() buffer */) 208b52f00e6SAlexei Starovoitov 209177366bfSAlexei Starovoitov #define PROLOGUE_SIZE 37 210b52f00e6SAlexei Starovoitov 211b52f00e6SAlexei Starovoitov /* emit x64 prologue code for BPF program and check it's size. 212b52f00e6SAlexei Starovoitov * bpf_tail_call helper will skip it while jumping into another program 213b52f00e6SAlexei Starovoitov */ 2142960ae48SAlexei Starovoitov static void emit_prologue(u8 **pprog, u32 stack_depth) 2150a14842fSEric Dumazet { 216b52f00e6SAlexei Starovoitov u8 *prog = *pprog; 217b52f00e6SAlexei Starovoitov int cnt = 0; 2180a14842fSEric Dumazet 21962258278SAlexei Starovoitov EMIT1(0x55); /* push rbp */ 22062258278SAlexei Starovoitov EMIT3(0x48, 0x89, 0xE5); /* mov rbp,rsp */ 2210a14842fSEric Dumazet 2222960ae48SAlexei Starovoitov /* sub rsp, rounded_stack_depth + AUX_STACK_SPACE */ 2232960ae48SAlexei Starovoitov EMIT3_off32(0x48, 0x81, 0xEC, 2242960ae48SAlexei Starovoitov round_up(stack_depth, 8) + AUX_STACK_SPACE); 225177366bfSAlexei Starovoitov 226177366bfSAlexei Starovoitov /* sub rbp, AUX_STACK_SPACE */ 227177366bfSAlexei Starovoitov EMIT4(0x48, 0x83, 0xED, AUX_STACK_SPACE); 2280a14842fSEric Dumazet 22962258278SAlexei Starovoitov /* all classic BPF filters use R6(rbx) save it */ 23062258278SAlexei Starovoitov 231177366bfSAlexei Starovoitov /* mov qword ptr [rbp+0],rbx */ 232177366bfSAlexei Starovoitov EMIT4(0x48, 0x89, 0x5D, 0); 23362258278SAlexei Starovoitov 2348fb575caSAlexei Starovoitov /* bpf_convert_filter() maps classic BPF register X to R7 and uses R8 23562258278SAlexei Starovoitov * as temporary, so all tcpdump filters need to spill/fill R7(r13) and 23662258278SAlexei Starovoitov * R8(r14). R9(r15) spill could be made conditional, but there is only 23762258278SAlexei Starovoitov * one 'bpf_error' return path out of helper functions inside bpf_jit.S 23862258278SAlexei Starovoitov * The overhead of extra spill is negligible for any filter other 23962258278SAlexei Starovoitov * than synthetic ones. Therefore not worth adding complexity. 2400a14842fSEric Dumazet */ 24162258278SAlexei Starovoitov 242177366bfSAlexei Starovoitov /* mov qword ptr [rbp+8],r13 */ 243177366bfSAlexei Starovoitov EMIT4(0x4C, 0x89, 0x6D, 8); 244177366bfSAlexei Starovoitov /* mov qword ptr [rbp+16],r14 */ 245177366bfSAlexei Starovoitov EMIT4(0x4C, 0x89, 0x75, 16); 246177366bfSAlexei Starovoitov /* mov qword ptr [rbp+24],r15 */ 247177366bfSAlexei Starovoitov EMIT4(0x4C, 0x89, 0x7D, 24); 24862258278SAlexei Starovoitov 2498b614aebSDaniel Borkmann /* Clear the tail call counter (tail_call_cnt): for eBPF tail calls 2508b614aebSDaniel Borkmann * we need to reset the counter to 0. It's done in two instructions, 2518b614aebSDaniel Borkmann * resetting rax register to 0 (xor on eax gets 0 extended), and 2528b614aebSDaniel Borkmann * moving it to the counter location. 2538b614aebSDaniel Borkmann */ 25462258278SAlexei Starovoitov 2558b614aebSDaniel Borkmann /* xor eax, eax */ 2568b614aebSDaniel Borkmann EMIT2(0x31, 0xc0); 257177366bfSAlexei Starovoitov /* mov qword ptr [rbp+32], rax */ 258177366bfSAlexei Starovoitov EMIT4(0x48, 0x89, 0x45, 32); 259b52f00e6SAlexei Starovoitov 260b52f00e6SAlexei Starovoitov BUILD_BUG_ON(cnt != PROLOGUE_SIZE); 261b52f00e6SAlexei Starovoitov *pprog = prog; 262b52f00e6SAlexei Starovoitov } 263b52f00e6SAlexei Starovoitov 264b52f00e6SAlexei Starovoitov /* generate the following code: 265b52f00e6SAlexei Starovoitov * ... bpf_tail_call(void *ctx, struct bpf_array *array, u64 index) ... 266b52f00e6SAlexei Starovoitov * if (index >= array->map.max_entries) 267b52f00e6SAlexei Starovoitov * goto out; 268b52f00e6SAlexei Starovoitov * if (++tail_call_cnt > MAX_TAIL_CALL_CNT) 269b52f00e6SAlexei Starovoitov * goto out; 2702a36f0b9SWang Nan * prog = array->ptrs[index]; 271b52f00e6SAlexei Starovoitov * if (prog == NULL) 272b52f00e6SAlexei Starovoitov * goto out; 273b52f00e6SAlexei Starovoitov * goto *(prog->bpf_func + prologue_size); 274b52f00e6SAlexei Starovoitov * out: 275b52f00e6SAlexei Starovoitov */ 276b52f00e6SAlexei Starovoitov static void emit_bpf_tail_call(u8 **pprog) 277b52f00e6SAlexei Starovoitov { 278b52f00e6SAlexei Starovoitov u8 *prog = *pprog; 279b52f00e6SAlexei Starovoitov int label1, label2, label3; 280b52f00e6SAlexei Starovoitov int cnt = 0; 281b52f00e6SAlexei Starovoitov 282b52f00e6SAlexei Starovoitov /* rdi - pointer to ctx 283b52f00e6SAlexei Starovoitov * rsi - pointer to bpf_array 284b52f00e6SAlexei Starovoitov * rdx - index in bpf_array 285b52f00e6SAlexei Starovoitov */ 286b52f00e6SAlexei Starovoitov 287b52f00e6SAlexei Starovoitov /* if (index >= array->map.max_entries) 288b52f00e6SAlexei Starovoitov * goto out; 289b52f00e6SAlexei Starovoitov */ 29090caccddSAlexei Starovoitov EMIT2(0x89, 0xD2); /* mov edx, edx */ 29190caccddSAlexei Starovoitov EMIT3(0x39, 0x56, /* cmp dword ptr [rsi + 16], edx */ 292b52f00e6SAlexei Starovoitov offsetof(struct bpf_array, map.max_entries)); 29384ccac6eSEric Dumazet #define OFFSET1 43 /* number of bytes to jump */ 294b52f00e6SAlexei Starovoitov EMIT2(X86_JBE, OFFSET1); /* jbe out */ 295b52f00e6SAlexei Starovoitov label1 = cnt; 296b52f00e6SAlexei Starovoitov 297b52f00e6SAlexei Starovoitov /* if (tail_call_cnt > MAX_TAIL_CALL_CNT) 298b52f00e6SAlexei Starovoitov * goto out; 299b52f00e6SAlexei Starovoitov */ 300177366bfSAlexei Starovoitov EMIT2_off32(0x8B, 0x85, 36); /* mov eax, dword ptr [rbp + 36] */ 301b52f00e6SAlexei Starovoitov EMIT3(0x83, 0xF8, MAX_TAIL_CALL_CNT); /* cmp eax, MAX_TAIL_CALL_CNT */ 30284ccac6eSEric Dumazet #define OFFSET2 32 303b52f00e6SAlexei Starovoitov EMIT2(X86_JA, OFFSET2); /* ja out */ 304b52f00e6SAlexei Starovoitov label2 = cnt; 305b52f00e6SAlexei Starovoitov EMIT3(0x83, 0xC0, 0x01); /* add eax, 1 */ 306177366bfSAlexei Starovoitov EMIT2_off32(0x89, 0x85, 36); /* mov dword ptr [rbp + 36], eax */ 307b52f00e6SAlexei Starovoitov 3082a36f0b9SWang Nan /* prog = array->ptrs[index]; */ 30984ccac6eSEric Dumazet EMIT4_off32(0x48, 0x8B, 0x84, 0xD6, /* mov rax, [rsi + rdx * 8 + offsetof(...)] */ 3102a36f0b9SWang Nan offsetof(struct bpf_array, ptrs)); 311b52f00e6SAlexei Starovoitov 312b52f00e6SAlexei Starovoitov /* if (prog == NULL) 313b52f00e6SAlexei Starovoitov * goto out; 314b52f00e6SAlexei Starovoitov */ 31584ccac6eSEric Dumazet EMIT3(0x48, 0x85, 0xC0); /* test rax,rax */ 316b52f00e6SAlexei Starovoitov #define OFFSET3 10 317b52f00e6SAlexei Starovoitov EMIT2(X86_JE, OFFSET3); /* je out */ 318b52f00e6SAlexei Starovoitov label3 = cnt; 319b52f00e6SAlexei Starovoitov 320b52f00e6SAlexei Starovoitov /* goto *(prog->bpf_func + prologue_size); */ 321b52f00e6SAlexei Starovoitov EMIT4(0x48, 0x8B, 0x40, /* mov rax, qword ptr [rax + 32] */ 322b52f00e6SAlexei Starovoitov offsetof(struct bpf_prog, bpf_func)); 323b52f00e6SAlexei Starovoitov EMIT4(0x48, 0x83, 0xC0, PROLOGUE_SIZE); /* add rax, prologue_size */ 324b52f00e6SAlexei Starovoitov 325b52f00e6SAlexei Starovoitov /* now we're ready to jump into next BPF program 326b52f00e6SAlexei Starovoitov * rdi == ctx (1st arg) 327b52f00e6SAlexei Starovoitov * rax == prog->bpf_func + prologue_size 328b52f00e6SAlexei Starovoitov */ 329b52f00e6SAlexei Starovoitov EMIT2(0xFF, 0xE0); /* jmp rax */ 330b52f00e6SAlexei Starovoitov 331b52f00e6SAlexei Starovoitov /* out: */ 332b52f00e6SAlexei Starovoitov BUILD_BUG_ON(cnt - label1 != OFFSET1); 333b52f00e6SAlexei Starovoitov BUILD_BUG_ON(cnt - label2 != OFFSET2); 334b52f00e6SAlexei Starovoitov BUILD_BUG_ON(cnt - label3 != OFFSET3); 335b52f00e6SAlexei Starovoitov *pprog = prog; 336b52f00e6SAlexei Starovoitov } 337b52f00e6SAlexei Starovoitov 3384e10df9aSAlexei Starovoitov 3394e10df9aSAlexei Starovoitov static void emit_load_skb_data_hlen(u8 **pprog) 3404e10df9aSAlexei Starovoitov { 3414e10df9aSAlexei Starovoitov u8 *prog = *pprog; 3424e10df9aSAlexei Starovoitov int cnt = 0; 3434e10df9aSAlexei Starovoitov 3444e10df9aSAlexei Starovoitov /* r9d = skb->len - skb->data_len (headlen) 3454e10df9aSAlexei Starovoitov * r10 = skb->data 3464e10df9aSAlexei Starovoitov */ 3474e10df9aSAlexei Starovoitov /* mov %r9d, off32(%rdi) */ 3484e10df9aSAlexei Starovoitov EMIT3_off32(0x44, 0x8b, 0x8f, offsetof(struct sk_buff, len)); 3494e10df9aSAlexei Starovoitov 3504e10df9aSAlexei Starovoitov /* sub %r9d, off32(%rdi) */ 3514e10df9aSAlexei Starovoitov EMIT3_off32(0x44, 0x2b, 0x8f, offsetof(struct sk_buff, data_len)); 3524e10df9aSAlexei Starovoitov 3534e10df9aSAlexei Starovoitov /* mov %r10, off32(%rdi) */ 3544e10df9aSAlexei Starovoitov EMIT3_off32(0x4c, 0x8b, 0x97, offsetof(struct sk_buff, data)); 3554e10df9aSAlexei Starovoitov *pprog = prog; 3564e10df9aSAlexei Starovoitov } 3574e10df9aSAlexei Starovoitov 358b52f00e6SAlexei Starovoitov static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image, 359b52f00e6SAlexei Starovoitov int oldproglen, struct jit_context *ctx) 360b52f00e6SAlexei Starovoitov { 361b52f00e6SAlexei Starovoitov struct bpf_insn *insn = bpf_prog->insnsi; 362b52f00e6SAlexei Starovoitov int insn_cnt = bpf_prog->len; 363b52f00e6SAlexei Starovoitov bool seen_ld_abs = ctx->seen_ld_abs | (oldproglen == 0); 364959a7579SDaniel Borkmann bool seen_ax_reg = ctx->seen_ax_reg | (oldproglen == 0); 365b52f00e6SAlexei Starovoitov bool seen_exit = false; 366b52f00e6SAlexei Starovoitov u8 temp[BPF_MAX_INSN_SIZE + BPF_INSN_SAFETY]; 367b52f00e6SAlexei Starovoitov int i, cnt = 0; 368b52f00e6SAlexei Starovoitov int proglen = 0; 369b52f00e6SAlexei Starovoitov u8 *prog = temp; 370b52f00e6SAlexei Starovoitov 3712960ae48SAlexei Starovoitov emit_prologue(&prog, bpf_prog->aux->stack_depth); 372b52f00e6SAlexei Starovoitov 3734e10df9aSAlexei Starovoitov if (seen_ld_abs) 3744e10df9aSAlexei Starovoitov emit_load_skb_data_hlen(&prog); 37562258278SAlexei Starovoitov 37662258278SAlexei Starovoitov for (i = 0; i < insn_cnt; i++, insn++) { 377e430f34eSAlexei Starovoitov const s32 imm32 = insn->imm; 378e430f34eSAlexei Starovoitov u32 dst_reg = insn->dst_reg; 379e430f34eSAlexei Starovoitov u32 src_reg = insn->src_reg; 38062258278SAlexei Starovoitov u8 b1 = 0, b2 = 0, b3 = 0; 38162258278SAlexei Starovoitov s64 jmp_offset; 38262258278SAlexei Starovoitov u8 jmp_cond; 3834e10df9aSAlexei Starovoitov bool reload_skb_data; 38462258278SAlexei Starovoitov int ilen; 38562258278SAlexei Starovoitov u8 *func; 38662258278SAlexei Starovoitov 387959a7579SDaniel Borkmann if (dst_reg == BPF_REG_AX || src_reg == BPF_REG_AX) 388959a7579SDaniel Borkmann ctx->seen_ax_reg = seen_ax_reg = true; 389959a7579SDaniel Borkmann 39062258278SAlexei Starovoitov switch (insn->code) { 39162258278SAlexei Starovoitov /* ALU */ 39262258278SAlexei Starovoitov case BPF_ALU | BPF_ADD | BPF_X: 39362258278SAlexei Starovoitov case BPF_ALU | BPF_SUB | BPF_X: 39462258278SAlexei Starovoitov case BPF_ALU | BPF_AND | BPF_X: 39562258278SAlexei Starovoitov case BPF_ALU | BPF_OR | BPF_X: 39662258278SAlexei Starovoitov case BPF_ALU | BPF_XOR | BPF_X: 39762258278SAlexei Starovoitov case BPF_ALU64 | BPF_ADD | BPF_X: 39862258278SAlexei Starovoitov case BPF_ALU64 | BPF_SUB | BPF_X: 39962258278SAlexei Starovoitov case BPF_ALU64 | BPF_AND | BPF_X: 40062258278SAlexei Starovoitov case BPF_ALU64 | BPF_OR | BPF_X: 40162258278SAlexei Starovoitov case BPF_ALU64 | BPF_XOR | BPF_X: 40262258278SAlexei Starovoitov switch (BPF_OP(insn->code)) { 40362258278SAlexei Starovoitov case BPF_ADD: b2 = 0x01; break; 40462258278SAlexei Starovoitov case BPF_SUB: b2 = 0x29; break; 40562258278SAlexei Starovoitov case BPF_AND: b2 = 0x21; break; 40662258278SAlexei Starovoitov case BPF_OR: b2 = 0x09; break; 40762258278SAlexei Starovoitov case BPF_XOR: b2 = 0x31; break; 40862258278SAlexei Starovoitov } 40962258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 410e430f34eSAlexei Starovoitov EMIT1(add_2mod(0x48, dst_reg, src_reg)); 411e430f34eSAlexei Starovoitov else if (is_ereg(dst_reg) || is_ereg(src_reg)) 412e430f34eSAlexei Starovoitov EMIT1(add_2mod(0x40, dst_reg, src_reg)); 413e430f34eSAlexei Starovoitov EMIT2(b2, add_2reg(0xC0, dst_reg, src_reg)); 4140a14842fSEric Dumazet break; 41562258278SAlexei Starovoitov 416e430f34eSAlexei Starovoitov /* mov dst, src */ 41762258278SAlexei Starovoitov case BPF_ALU64 | BPF_MOV | BPF_X: 418e430f34eSAlexei Starovoitov EMIT_mov(dst_reg, src_reg); 41962258278SAlexei Starovoitov break; 42062258278SAlexei Starovoitov 421e430f34eSAlexei Starovoitov /* mov32 dst, src */ 42262258278SAlexei Starovoitov case BPF_ALU | BPF_MOV | BPF_X: 423e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 424e430f34eSAlexei Starovoitov EMIT1(add_2mod(0x40, dst_reg, src_reg)); 425e430f34eSAlexei Starovoitov EMIT2(0x89, add_2reg(0xC0, dst_reg, src_reg)); 42662258278SAlexei Starovoitov break; 42762258278SAlexei Starovoitov 428e430f34eSAlexei Starovoitov /* neg dst */ 42962258278SAlexei Starovoitov case BPF_ALU | BPF_NEG: 43062258278SAlexei Starovoitov case BPF_ALU64 | BPF_NEG: 43162258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 432e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 433e430f34eSAlexei Starovoitov else if (is_ereg(dst_reg)) 434e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x40, dst_reg)); 435e430f34eSAlexei Starovoitov EMIT2(0xF7, add_1reg(0xD8, dst_reg)); 43662258278SAlexei Starovoitov break; 43762258278SAlexei Starovoitov 43862258278SAlexei Starovoitov case BPF_ALU | BPF_ADD | BPF_K: 43962258278SAlexei Starovoitov case BPF_ALU | BPF_SUB | BPF_K: 44062258278SAlexei Starovoitov case BPF_ALU | BPF_AND | BPF_K: 44162258278SAlexei Starovoitov case BPF_ALU | BPF_OR | BPF_K: 44262258278SAlexei Starovoitov case BPF_ALU | BPF_XOR | BPF_K: 44362258278SAlexei Starovoitov case BPF_ALU64 | BPF_ADD | BPF_K: 44462258278SAlexei Starovoitov case BPF_ALU64 | BPF_SUB | BPF_K: 44562258278SAlexei Starovoitov case BPF_ALU64 | BPF_AND | BPF_K: 44662258278SAlexei Starovoitov case BPF_ALU64 | BPF_OR | BPF_K: 44762258278SAlexei Starovoitov case BPF_ALU64 | BPF_XOR | BPF_K: 44862258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 449e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 450e430f34eSAlexei Starovoitov else if (is_ereg(dst_reg)) 451e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x40, dst_reg)); 45262258278SAlexei Starovoitov 453de0a444dSDaniel Borkmann /* b3 holds 'normal' opcode, b2 short form only valid 454de0a444dSDaniel Borkmann * in case dst is eax/rax. 455de0a444dSDaniel Borkmann */ 45662258278SAlexei Starovoitov switch (BPF_OP(insn->code)) { 457de0a444dSDaniel Borkmann case BPF_ADD: 458de0a444dSDaniel Borkmann b3 = 0xC0; 459de0a444dSDaniel Borkmann b2 = 0x05; 460de0a444dSDaniel Borkmann break; 461de0a444dSDaniel Borkmann case BPF_SUB: 462de0a444dSDaniel Borkmann b3 = 0xE8; 463de0a444dSDaniel Borkmann b2 = 0x2D; 464de0a444dSDaniel Borkmann break; 465de0a444dSDaniel Borkmann case BPF_AND: 466de0a444dSDaniel Borkmann b3 = 0xE0; 467de0a444dSDaniel Borkmann b2 = 0x25; 468de0a444dSDaniel Borkmann break; 469de0a444dSDaniel Borkmann case BPF_OR: 470de0a444dSDaniel Borkmann b3 = 0xC8; 471de0a444dSDaniel Borkmann b2 = 0x0D; 472de0a444dSDaniel Borkmann break; 473de0a444dSDaniel Borkmann case BPF_XOR: 474de0a444dSDaniel Borkmann b3 = 0xF0; 475de0a444dSDaniel Borkmann b2 = 0x35; 476de0a444dSDaniel Borkmann break; 47762258278SAlexei Starovoitov } 47862258278SAlexei Starovoitov 479e430f34eSAlexei Starovoitov if (is_imm8(imm32)) 480e430f34eSAlexei Starovoitov EMIT3(0x83, add_1reg(b3, dst_reg), imm32); 481de0a444dSDaniel Borkmann else if (is_axreg(dst_reg)) 482de0a444dSDaniel Borkmann EMIT1_off32(b2, imm32); 48362258278SAlexei Starovoitov else 484e430f34eSAlexei Starovoitov EMIT2_off32(0x81, add_1reg(b3, dst_reg), imm32); 48562258278SAlexei Starovoitov break; 48662258278SAlexei Starovoitov 48762258278SAlexei Starovoitov case BPF_ALU64 | BPF_MOV | BPF_K: 48862258278SAlexei Starovoitov /* optimization: if imm32 is positive, 48962258278SAlexei Starovoitov * use 'mov eax, imm32' (which zero-extends imm32) 49062258278SAlexei Starovoitov * to save 2 bytes 491d00a9dd2SEric Dumazet */ 492e430f34eSAlexei Starovoitov if (imm32 < 0) { 49362258278SAlexei Starovoitov /* 'mov rax, imm32' sign extends imm32 */ 494e430f34eSAlexei Starovoitov b1 = add_1mod(0x48, dst_reg); 49562258278SAlexei Starovoitov b2 = 0xC7; 49662258278SAlexei Starovoitov b3 = 0xC0; 497e430f34eSAlexei Starovoitov EMIT3_off32(b1, b2, add_1reg(b3, dst_reg), imm32); 498aee636c4SEric Dumazet break; 499aee636c4SEric Dumazet } 5003b58908aSEric Dumazet 50162258278SAlexei Starovoitov case BPF_ALU | BPF_MOV | BPF_K: 502606c88a8SDaniel Borkmann /* optimization: if imm32 is zero, use 'xor <dst>,<dst>' 503606c88a8SDaniel Borkmann * to save 3 bytes. 504606c88a8SDaniel Borkmann */ 505606c88a8SDaniel Borkmann if (imm32 == 0) { 506606c88a8SDaniel Borkmann if (is_ereg(dst_reg)) 507606c88a8SDaniel Borkmann EMIT1(add_2mod(0x40, dst_reg, dst_reg)); 508606c88a8SDaniel Borkmann b2 = 0x31; /* xor */ 509606c88a8SDaniel Borkmann b3 = 0xC0; 510606c88a8SDaniel Borkmann EMIT2(b2, add_2reg(b3, dst_reg, dst_reg)); 511606c88a8SDaniel Borkmann break; 512606c88a8SDaniel Borkmann } 513606c88a8SDaniel Borkmann 51462258278SAlexei Starovoitov /* mov %eax, imm32 */ 515e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 516e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x40, dst_reg)); 517e430f34eSAlexei Starovoitov EMIT1_off32(add_1reg(0xB8, dst_reg), imm32); 51862258278SAlexei Starovoitov break; 51962258278SAlexei Starovoitov 52002ab695bSAlexei Starovoitov case BPF_LD | BPF_IMM | BPF_DW: 521606c88a8SDaniel Borkmann /* optimization: if imm64 is zero, use 'xor <dst>,<dst>' 522606c88a8SDaniel Borkmann * to save 7 bytes. 523606c88a8SDaniel Borkmann */ 524606c88a8SDaniel Borkmann if (insn[0].imm == 0 && insn[1].imm == 0) { 525606c88a8SDaniel Borkmann b1 = add_2mod(0x48, dst_reg, dst_reg); 526606c88a8SDaniel Borkmann b2 = 0x31; /* xor */ 527606c88a8SDaniel Borkmann b3 = 0xC0; 528606c88a8SDaniel Borkmann EMIT3(b1, b2, add_2reg(b3, dst_reg, dst_reg)); 529606c88a8SDaniel Borkmann 530606c88a8SDaniel Borkmann insn++; 531606c88a8SDaniel Borkmann i++; 532606c88a8SDaniel Borkmann break; 533606c88a8SDaniel Borkmann } 534606c88a8SDaniel Borkmann 53502ab695bSAlexei Starovoitov /* movabsq %rax, imm64 */ 53602ab695bSAlexei Starovoitov EMIT2(add_1mod(0x48, dst_reg), add_1reg(0xB8, dst_reg)); 53702ab695bSAlexei Starovoitov EMIT(insn[0].imm, 4); 53802ab695bSAlexei Starovoitov EMIT(insn[1].imm, 4); 53902ab695bSAlexei Starovoitov 54002ab695bSAlexei Starovoitov insn++; 54102ab695bSAlexei Starovoitov i++; 54202ab695bSAlexei Starovoitov break; 54302ab695bSAlexei Starovoitov 544e430f34eSAlexei Starovoitov /* dst %= src, dst /= src, dst %= imm32, dst /= imm32 */ 54562258278SAlexei Starovoitov case BPF_ALU | BPF_MOD | BPF_X: 54662258278SAlexei Starovoitov case BPF_ALU | BPF_DIV | BPF_X: 54762258278SAlexei Starovoitov case BPF_ALU | BPF_MOD | BPF_K: 54862258278SAlexei Starovoitov case BPF_ALU | BPF_DIV | BPF_K: 54962258278SAlexei Starovoitov case BPF_ALU64 | BPF_MOD | BPF_X: 55062258278SAlexei Starovoitov case BPF_ALU64 | BPF_DIV | BPF_X: 55162258278SAlexei Starovoitov case BPF_ALU64 | BPF_MOD | BPF_K: 55262258278SAlexei Starovoitov case BPF_ALU64 | BPF_DIV | BPF_K: 55362258278SAlexei Starovoitov EMIT1(0x50); /* push rax */ 55462258278SAlexei Starovoitov EMIT1(0x52); /* push rdx */ 55562258278SAlexei Starovoitov 55662258278SAlexei Starovoitov if (BPF_SRC(insn->code) == BPF_X) 557e430f34eSAlexei Starovoitov /* mov r11, src_reg */ 558e430f34eSAlexei Starovoitov EMIT_mov(AUX_REG, src_reg); 55962258278SAlexei Starovoitov else 560e430f34eSAlexei Starovoitov /* mov r11, imm32 */ 561e430f34eSAlexei Starovoitov EMIT3_off32(0x49, 0xC7, 0xC3, imm32); 56262258278SAlexei Starovoitov 563e430f34eSAlexei Starovoitov /* mov rax, dst_reg */ 564e430f34eSAlexei Starovoitov EMIT_mov(BPF_REG_0, dst_reg); 56562258278SAlexei Starovoitov 56662258278SAlexei Starovoitov /* xor edx, edx 56762258278SAlexei Starovoitov * equivalent to 'xor rdx, rdx', but one byte less 56862258278SAlexei Starovoitov */ 56962258278SAlexei Starovoitov EMIT2(0x31, 0xd2); 57062258278SAlexei Starovoitov 57162258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 57262258278SAlexei Starovoitov /* div r11 */ 57362258278SAlexei Starovoitov EMIT3(0x49, 0xF7, 0xF3); 57462258278SAlexei Starovoitov else 57562258278SAlexei Starovoitov /* div r11d */ 57662258278SAlexei Starovoitov EMIT3(0x41, 0xF7, 0xF3); 57762258278SAlexei Starovoitov 57862258278SAlexei Starovoitov if (BPF_OP(insn->code) == BPF_MOD) 57962258278SAlexei Starovoitov /* mov r11, rdx */ 58062258278SAlexei Starovoitov EMIT3(0x49, 0x89, 0xD3); 58162258278SAlexei Starovoitov else 58262258278SAlexei Starovoitov /* mov r11, rax */ 58362258278SAlexei Starovoitov EMIT3(0x49, 0x89, 0xC3); 58462258278SAlexei Starovoitov 58562258278SAlexei Starovoitov EMIT1(0x5A); /* pop rdx */ 58662258278SAlexei Starovoitov EMIT1(0x58); /* pop rax */ 58762258278SAlexei Starovoitov 588e430f34eSAlexei Starovoitov /* mov dst_reg, r11 */ 589e430f34eSAlexei Starovoitov EMIT_mov(dst_reg, AUX_REG); 59062258278SAlexei Starovoitov break; 59162258278SAlexei Starovoitov 59262258278SAlexei Starovoitov case BPF_ALU | BPF_MUL | BPF_K: 59362258278SAlexei Starovoitov case BPF_ALU | BPF_MUL | BPF_X: 59462258278SAlexei Starovoitov case BPF_ALU64 | BPF_MUL | BPF_K: 59562258278SAlexei Starovoitov case BPF_ALU64 | BPF_MUL | BPF_X: 59662258278SAlexei Starovoitov EMIT1(0x50); /* push rax */ 59762258278SAlexei Starovoitov EMIT1(0x52); /* push rdx */ 59862258278SAlexei Starovoitov 599e430f34eSAlexei Starovoitov /* mov r11, dst_reg */ 600e430f34eSAlexei Starovoitov EMIT_mov(AUX_REG, dst_reg); 60162258278SAlexei Starovoitov 60262258278SAlexei Starovoitov if (BPF_SRC(insn->code) == BPF_X) 603e430f34eSAlexei Starovoitov /* mov rax, src_reg */ 604e430f34eSAlexei Starovoitov EMIT_mov(BPF_REG_0, src_reg); 60562258278SAlexei Starovoitov else 606e430f34eSAlexei Starovoitov /* mov rax, imm32 */ 607e430f34eSAlexei Starovoitov EMIT3_off32(0x48, 0xC7, 0xC0, imm32); 60862258278SAlexei Starovoitov 60962258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 61062258278SAlexei Starovoitov EMIT1(add_1mod(0x48, AUX_REG)); 61162258278SAlexei Starovoitov else if (is_ereg(AUX_REG)) 61262258278SAlexei Starovoitov EMIT1(add_1mod(0x40, AUX_REG)); 61362258278SAlexei Starovoitov /* mul(q) r11 */ 61462258278SAlexei Starovoitov EMIT2(0xF7, add_1reg(0xE0, AUX_REG)); 61562258278SAlexei Starovoitov 61662258278SAlexei Starovoitov /* mov r11, rax */ 61762258278SAlexei Starovoitov EMIT_mov(AUX_REG, BPF_REG_0); 61862258278SAlexei Starovoitov 61962258278SAlexei Starovoitov EMIT1(0x5A); /* pop rdx */ 62062258278SAlexei Starovoitov EMIT1(0x58); /* pop rax */ 62162258278SAlexei Starovoitov 622e430f34eSAlexei Starovoitov /* mov dst_reg, r11 */ 623e430f34eSAlexei Starovoitov EMIT_mov(dst_reg, AUX_REG); 62462258278SAlexei Starovoitov break; 62562258278SAlexei Starovoitov 62662258278SAlexei Starovoitov /* shifts */ 62762258278SAlexei Starovoitov case BPF_ALU | BPF_LSH | BPF_K: 62862258278SAlexei Starovoitov case BPF_ALU | BPF_RSH | BPF_K: 62962258278SAlexei Starovoitov case BPF_ALU | BPF_ARSH | BPF_K: 63062258278SAlexei Starovoitov case BPF_ALU64 | BPF_LSH | BPF_K: 63162258278SAlexei Starovoitov case BPF_ALU64 | BPF_RSH | BPF_K: 63262258278SAlexei Starovoitov case BPF_ALU64 | BPF_ARSH | BPF_K: 63362258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 634e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 635e430f34eSAlexei Starovoitov else if (is_ereg(dst_reg)) 636e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x40, dst_reg)); 63762258278SAlexei Starovoitov 63862258278SAlexei Starovoitov switch (BPF_OP(insn->code)) { 63962258278SAlexei Starovoitov case BPF_LSH: b3 = 0xE0; break; 64062258278SAlexei Starovoitov case BPF_RSH: b3 = 0xE8; break; 64162258278SAlexei Starovoitov case BPF_ARSH: b3 = 0xF8; break; 64262258278SAlexei Starovoitov } 64388e69a1fSDaniel Borkmann 64488e69a1fSDaniel Borkmann if (imm32 == 1) 64588e69a1fSDaniel Borkmann EMIT2(0xD1, add_1reg(b3, dst_reg)); 64688e69a1fSDaniel Borkmann else 647e430f34eSAlexei Starovoitov EMIT3(0xC1, add_1reg(b3, dst_reg), imm32); 64862258278SAlexei Starovoitov break; 64962258278SAlexei Starovoitov 65072b603eeSAlexei Starovoitov case BPF_ALU | BPF_LSH | BPF_X: 65172b603eeSAlexei Starovoitov case BPF_ALU | BPF_RSH | BPF_X: 65272b603eeSAlexei Starovoitov case BPF_ALU | BPF_ARSH | BPF_X: 65372b603eeSAlexei Starovoitov case BPF_ALU64 | BPF_LSH | BPF_X: 65472b603eeSAlexei Starovoitov case BPF_ALU64 | BPF_RSH | BPF_X: 65572b603eeSAlexei Starovoitov case BPF_ALU64 | BPF_ARSH | BPF_X: 65672b603eeSAlexei Starovoitov 65772b603eeSAlexei Starovoitov /* check for bad case when dst_reg == rcx */ 65872b603eeSAlexei Starovoitov if (dst_reg == BPF_REG_4) { 65972b603eeSAlexei Starovoitov /* mov r11, dst_reg */ 66072b603eeSAlexei Starovoitov EMIT_mov(AUX_REG, dst_reg); 66172b603eeSAlexei Starovoitov dst_reg = AUX_REG; 66272b603eeSAlexei Starovoitov } 66372b603eeSAlexei Starovoitov 66472b603eeSAlexei Starovoitov if (src_reg != BPF_REG_4) { /* common case */ 66572b603eeSAlexei Starovoitov EMIT1(0x51); /* push rcx */ 66672b603eeSAlexei Starovoitov 66772b603eeSAlexei Starovoitov /* mov rcx, src_reg */ 66872b603eeSAlexei Starovoitov EMIT_mov(BPF_REG_4, src_reg); 66972b603eeSAlexei Starovoitov } 67072b603eeSAlexei Starovoitov 67172b603eeSAlexei Starovoitov /* shl %rax, %cl | shr %rax, %cl | sar %rax, %cl */ 67272b603eeSAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 67372b603eeSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 67472b603eeSAlexei Starovoitov else if (is_ereg(dst_reg)) 67572b603eeSAlexei Starovoitov EMIT1(add_1mod(0x40, dst_reg)); 67672b603eeSAlexei Starovoitov 67772b603eeSAlexei Starovoitov switch (BPF_OP(insn->code)) { 67872b603eeSAlexei Starovoitov case BPF_LSH: b3 = 0xE0; break; 67972b603eeSAlexei Starovoitov case BPF_RSH: b3 = 0xE8; break; 68072b603eeSAlexei Starovoitov case BPF_ARSH: b3 = 0xF8; break; 68172b603eeSAlexei Starovoitov } 68272b603eeSAlexei Starovoitov EMIT2(0xD3, add_1reg(b3, dst_reg)); 68372b603eeSAlexei Starovoitov 68472b603eeSAlexei Starovoitov if (src_reg != BPF_REG_4) 68572b603eeSAlexei Starovoitov EMIT1(0x59); /* pop rcx */ 68672b603eeSAlexei Starovoitov 68772b603eeSAlexei Starovoitov if (insn->dst_reg == BPF_REG_4) 68872b603eeSAlexei Starovoitov /* mov dst_reg, r11 */ 68972b603eeSAlexei Starovoitov EMIT_mov(insn->dst_reg, AUX_REG); 69072b603eeSAlexei Starovoitov break; 69172b603eeSAlexei Starovoitov 69262258278SAlexei Starovoitov case BPF_ALU | BPF_END | BPF_FROM_BE: 693e430f34eSAlexei Starovoitov switch (imm32) { 69462258278SAlexei Starovoitov case 16: 69562258278SAlexei Starovoitov /* emit 'ror %ax, 8' to swap lower 2 bytes */ 69662258278SAlexei Starovoitov EMIT1(0x66); 697e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 69862258278SAlexei Starovoitov EMIT1(0x41); 699e430f34eSAlexei Starovoitov EMIT3(0xC1, add_1reg(0xC8, dst_reg), 8); 700343f845bSAlexei Starovoitov 701343f845bSAlexei Starovoitov /* emit 'movzwl eax, ax' */ 702343f845bSAlexei Starovoitov if (is_ereg(dst_reg)) 703343f845bSAlexei Starovoitov EMIT3(0x45, 0x0F, 0xB7); 704343f845bSAlexei Starovoitov else 705343f845bSAlexei Starovoitov EMIT2(0x0F, 0xB7); 706343f845bSAlexei Starovoitov EMIT1(add_2reg(0xC0, dst_reg, dst_reg)); 70762258278SAlexei Starovoitov break; 70862258278SAlexei Starovoitov case 32: 70962258278SAlexei Starovoitov /* emit 'bswap eax' to swap lower 4 bytes */ 710e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 71162258278SAlexei Starovoitov EMIT2(0x41, 0x0F); 71262258278SAlexei Starovoitov else 71362258278SAlexei Starovoitov EMIT1(0x0F); 714e430f34eSAlexei Starovoitov EMIT1(add_1reg(0xC8, dst_reg)); 71562258278SAlexei Starovoitov break; 71662258278SAlexei Starovoitov case 64: 71762258278SAlexei Starovoitov /* emit 'bswap rax' to swap 8 bytes */ 718e430f34eSAlexei Starovoitov EMIT3(add_1mod(0x48, dst_reg), 0x0F, 719e430f34eSAlexei Starovoitov add_1reg(0xC8, dst_reg)); 72062258278SAlexei Starovoitov break; 72162258278SAlexei Starovoitov } 72262258278SAlexei Starovoitov break; 72362258278SAlexei Starovoitov 72462258278SAlexei Starovoitov case BPF_ALU | BPF_END | BPF_FROM_LE: 725343f845bSAlexei Starovoitov switch (imm32) { 726343f845bSAlexei Starovoitov case 16: 727343f845bSAlexei Starovoitov /* emit 'movzwl eax, ax' to zero extend 16-bit 728343f845bSAlexei Starovoitov * into 64 bit 729343f845bSAlexei Starovoitov */ 730343f845bSAlexei Starovoitov if (is_ereg(dst_reg)) 731343f845bSAlexei Starovoitov EMIT3(0x45, 0x0F, 0xB7); 732343f845bSAlexei Starovoitov else 733343f845bSAlexei Starovoitov EMIT2(0x0F, 0xB7); 734343f845bSAlexei Starovoitov EMIT1(add_2reg(0xC0, dst_reg, dst_reg)); 735343f845bSAlexei Starovoitov break; 736343f845bSAlexei Starovoitov case 32: 737343f845bSAlexei Starovoitov /* emit 'mov eax, eax' to clear upper 32-bits */ 738343f845bSAlexei Starovoitov if (is_ereg(dst_reg)) 739343f845bSAlexei Starovoitov EMIT1(0x45); 740343f845bSAlexei Starovoitov EMIT2(0x89, add_2reg(0xC0, dst_reg, dst_reg)); 741343f845bSAlexei Starovoitov break; 742343f845bSAlexei Starovoitov case 64: 743343f845bSAlexei Starovoitov /* nop */ 744343f845bSAlexei Starovoitov break; 745343f845bSAlexei Starovoitov } 74662258278SAlexei Starovoitov break; 74762258278SAlexei Starovoitov 748e430f34eSAlexei Starovoitov /* ST: *(u8*)(dst_reg + off) = imm */ 74962258278SAlexei Starovoitov case BPF_ST | BPF_MEM | BPF_B: 750e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 75162258278SAlexei Starovoitov EMIT2(0x41, 0xC6); 75262258278SAlexei Starovoitov else 75362258278SAlexei Starovoitov EMIT1(0xC6); 75462258278SAlexei Starovoitov goto st; 75562258278SAlexei Starovoitov case BPF_ST | BPF_MEM | BPF_H: 756e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 75762258278SAlexei Starovoitov EMIT3(0x66, 0x41, 0xC7); 75862258278SAlexei Starovoitov else 75962258278SAlexei Starovoitov EMIT2(0x66, 0xC7); 76062258278SAlexei Starovoitov goto st; 76162258278SAlexei Starovoitov case BPF_ST | BPF_MEM | BPF_W: 762e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 76362258278SAlexei Starovoitov EMIT2(0x41, 0xC7); 76462258278SAlexei Starovoitov else 76562258278SAlexei Starovoitov EMIT1(0xC7); 76662258278SAlexei Starovoitov goto st; 76762258278SAlexei Starovoitov case BPF_ST | BPF_MEM | BPF_DW: 768e430f34eSAlexei Starovoitov EMIT2(add_1mod(0x48, dst_reg), 0xC7); 76962258278SAlexei Starovoitov 77062258278SAlexei Starovoitov st: if (is_imm8(insn->off)) 771e430f34eSAlexei Starovoitov EMIT2(add_1reg(0x40, dst_reg), insn->off); 77262258278SAlexei Starovoitov else 773e430f34eSAlexei Starovoitov EMIT1_off32(add_1reg(0x80, dst_reg), insn->off); 77462258278SAlexei Starovoitov 775e430f34eSAlexei Starovoitov EMIT(imm32, bpf_size_to_x86_bytes(BPF_SIZE(insn->code))); 77662258278SAlexei Starovoitov break; 77762258278SAlexei Starovoitov 778e430f34eSAlexei Starovoitov /* STX: *(u8*)(dst_reg + off) = src_reg */ 77962258278SAlexei Starovoitov case BPF_STX | BPF_MEM | BPF_B: 78062258278SAlexei Starovoitov /* emit 'mov byte ptr [rax + off], al' */ 781e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg) || 78262258278SAlexei Starovoitov /* have to add extra byte for x86 SIL, DIL regs */ 783e430f34eSAlexei Starovoitov src_reg == BPF_REG_1 || src_reg == BPF_REG_2) 784e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x40, dst_reg, src_reg), 0x88); 78562258278SAlexei Starovoitov else 78662258278SAlexei Starovoitov EMIT1(0x88); 78762258278SAlexei Starovoitov goto stx; 78862258278SAlexei Starovoitov case BPF_STX | BPF_MEM | BPF_H: 789e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 790e430f34eSAlexei Starovoitov EMIT3(0x66, add_2mod(0x40, dst_reg, src_reg), 0x89); 79162258278SAlexei Starovoitov else 79262258278SAlexei Starovoitov EMIT2(0x66, 0x89); 79362258278SAlexei Starovoitov goto stx; 79462258278SAlexei Starovoitov case BPF_STX | BPF_MEM | BPF_W: 795e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 796e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x40, dst_reg, src_reg), 0x89); 79762258278SAlexei Starovoitov else 79862258278SAlexei Starovoitov EMIT1(0x89); 79962258278SAlexei Starovoitov goto stx; 80062258278SAlexei Starovoitov case BPF_STX | BPF_MEM | BPF_DW: 801e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x48, dst_reg, src_reg), 0x89); 80262258278SAlexei Starovoitov stx: if (is_imm8(insn->off)) 803e430f34eSAlexei Starovoitov EMIT2(add_2reg(0x40, dst_reg, src_reg), insn->off); 80462258278SAlexei Starovoitov else 805e430f34eSAlexei Starovoitov EMIT1_off32(add_2reg(0x80, dst_reg, src_reg), 80662258278SAlexei Starovoitov insn->off); 80762258278SAlexei Starovoitov break; 80862258278SAlexei Starovoitov 809e430f34eSAlexei Starovoitov /* LDX: dst_reg = *(u8*)(src_reg + off) */ 81062258278SAlexei Starovoitov case BPF_LDX | BPF_MEM | BPF_B: 81162258278SAlexei Starovoitov /* emit 'movzx rax, byte ptr [rax + off]' */ 812e430f34eSAlexei Starovoitov EMIT3(add_2mod(0x48, src_reg, dst_reg), 0x0F, 0xB6); 81362258278SAlexei Starovoitov goto ldx; 81462258278SAlexei Starovoitov case BPF_LDX | BPF_MEM | BPF_H: 81562258278SAlexei Starovoitov /* emit 'movzx rax, word ptr [rax + off]' */ 816e430f34eSAlexei Starovoitov EMIT3(add_2mod(0x48, src_reg, dst_reg), 0x0F, 0xB7); 81762258278SAlexei Starovoitov goto ldx; 81862258278SAlexei Starovoitov case BPF_LDX | BPF_MEM | BPF_W: 81962258278SAlexei Starovoitov /* emit 'mov eax, dword ptr [rax+0x14]' */ 820e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 821e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x40, src_reg, dst_reg), 0x8B); 82262258278SAlexei Starovoitov else 82362258278SAlexei Starovoitov EMIT1(0x8B); 82462258278SAlexei Starovoitov goto ldx; 82562258278SAlexei Starovoitov case BPF_LDX | BPF_MEM | BPF_DW: 82662258278SAlexei Starovoitov /* emit 'mov rax, qword ptr [rax+0x14]' */ 827e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x48, src_reg, dst_reg), 0x8B); 82862258278SAlexei Starovoitov ldx: /* if insn->off == 0 we can save one extra byte, but 82962258278SAlexei Starovoitov * special case of x86 r13 which always needs an offset 83062258278SAlexei Starovoitov * is not worth the hassle 83162258278SAlexei Starovoitov */ 83262258278SAlexei Starovoitov if (is_imm8(insn->off)) 833e430f34eSAlexei Starovoitov EMIT2(add_2reg(0x40, src_reg, dst_reg), insn->off); 83462258278SAlexei Starovoitov else 835e430f34eSAlexei Starovoitov EMIT1_off32(add_2reg(0x80, src_reg, dst_reg), 83662258278SAlexei Starovoitov insn->off); 83762258278SAlexei Starovoitov break; 83862258278SAlexei Starovoitov 839e430f34eSAlexei Starovoitov /* STX XADD: lock *(u32*)(dst_reg + off) += src_reg */ 84062258278SAlexei Starovoitov case BPF_STX | BPF_XADD | BPF_W: 84162258278SAlexei Starovoitov /* emit 'lock add dword ptr [rax + off], eax' */ 842e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 843e430f34eSAlexei Starovoitov EMIT3(0xF0, add_2mod(0x40, dst_reg, src_reg), 0x01); 84462258278SAlexei Starovoitov else 84562258278SAlexei Starovoitov EMIT2(0xF0, 0x01); 84662258278SAlexei Starovoitov goto xadd; 84762258278SAlexei Starovoitov case BPF_STX | BPF_XADD | BPF_DW: 848e430f34eSAlexei Starovoitov EMIT3(0xF0, add_2mod(0x48, dst_reg, src_reg), 0x01); 84962258278SAlexei Starovoitov xadd: if (is_imm8(insn->off)) 850e430f34eSAlexei Starovoitov EMIT2(add_2reg(0x40, dst_reg, src_reg), insn->off); 85162258278SAlexei Starovoitov else 852e430f34eSAlexei Starovoitov EMIT1_off32(add_2reg(0x80, dst_reg, src_reg), 85362258278SAlexei Starovoitov insn->off); 85462258278SAlexei Starovoitov break; 85562258278SAlexei Starovoitov 85662258278SAlexei Starovoitov /* call */ 85762258278SAlexei Starovoitov case BPF_JMP | BPF_CALL: 858e430f34eSAlexei Starovoitov func = (u8 *) __bpf_call_base + imm32; 85962258278SAlexei Starovoitov jmp_offset = func - (image + addrs[i]); 860e0ee9c12SAlexei Starovoitov if (seen_ld_abs) { 86117bedab2SMartin KaFai Lau reload_skb_data = bpf_helper_changes_pkt_data(func); 8624e10df9aSAlexei Starovoitov if (reload_skb_data) { 8634e10df9aSAlexei Starovoitov EMIT1(0x57); /* push %rdi */ 8644e10df9aSAlexei Starovoitov jmp_offset += 22; /* pop, mov, sub, mov */ 8654e10df9aSAlexei Starovoitov } else { 86662258278SAlexei Starovoitov EMIT2(0x41, 0x52); /* push %r10 */ 86762258278SAlexei Starovoitov EMIT2(0x41, 0x51); /* push %r9 */ 86862258278SAlexei Starovoitov /* need to adjust jmp offset, since 86962258278SAlexei Starovoitov * pop %r9, pop %r10 take 4 bytes after call insn 87062258278SAlexei Starovoitov */ 87162258278SAlexei Starovoitov jmp_offset += 4; 87262258278SAlexei Starovoitov } 8734e10df9aSAlexei Starovoitov } 874e430f34eSAlexei Starovoitov if (!imm32 || !is_simm32(jmp_offset)) { 87562258278SAlexei Starovoitov pr_err("unsupported bpf func %d addr %p image %p\n", 876e430f34eSAlexei Starovoitov imm32, func, image); 877f3c2af7bSAlexei Starovoitov return -EINVAL; 87862258278SAlexei Starovoitov } 87962258278SAlexei Starovoitov EMIT1_off32(0xE8, jmp_offset); 880e0ee9c12SAlexei Starovoitov if (seen_ld_abs) { 8814e10df9aSAlexei Starovoitov if (reload_skb_data) { 8824e10df9aSAlexei Starovoitov EMIT1(0x5F); /* pop %rdi */ 8834e10df9aSAlexei Starovoitov emit_load_skb_data_hlen(&prog); 8844e10df9aSAlexei Starovoitov } else { 88562258278SAlexei Starovoitov EMIT2(0x41, 0x59); /* pop %r9 */ 88662258278SAlexei Starovoitov EMIT2(0x41, 0x5A); /* pop %r10 */ 88762258278SAlexei Starovoitov } 8884e10df9aSAlexei Starovoitov } 88962258278SAlexei Starovoitov break; 89062258278SAlexei Starovoitov 89171189fa9SAlexei Starovoitov case BPF_JMP | BPF_TAIL_CALL: 892b52f00e6SAlexei Starovoitov emit_bpf_tail_call(&prog); 893b52f00e6SAlexei Starovoitov break; 894b52f00e6SAlexei Starovoitov 89562258278SAlexei Starovoitov /* cond jump */ 89662258278SAlexei Starovoitov case BPF_JMP | BPF_JEQ | BPF_X: 89762258278SAlexei Starovoitov case BPF_JMP | BPF_JNE | BPF_X: 89862258278SAlexei Starovoitov case BPF_JMP | BPF_JGT | BPF_X: 89952afc51eSDaniel Borkmann case BPF_JMP | BPF_JLT | BPF_X: 90062258278SAlexei Starovoitov case BPF_JMP | BPF_JGE | BPF_X: 90152afc51eSDaniel Borkmann case BPF_JMP | BPF_JLE | BPF_X: 90262258278SAlexei Starovoitov case BPF_JMP | BPF_JSGT | BPF_X: 90352afc51eSDaniel Borkmann case BPF_JMP | BPF_JSLT | BPF_X: 90462258278SAlexei Starovoitov case BPF_JMP | BPF_JSGE | BPF_X: 90552afc51eSDaniel Borkmann case BPF_JMP | BPF_JSLE | BPF_X: 906e430f34eSAlexei Starovoitov /* cmp dst_reg, src_reg */ 907e430f34eSAlexei Starovoitov EMIT3(add_2mod(0x48, dst_reg, src_reg), 0x39, 908e430f34eSAlexei Starovoitov add_2reg(0xC0, dst_reg, src_reg)); 90962258278SAlexei Starovoitov goto emit_cond_jmp; 91062258278SAlexei Starovoitov 91162258278SAlexei Starovoitov case BPF_JMP | BPF_JSET | BPF_X: 912e430f34eSAlexei Starovoitov /* test dst_reg, src_reg */ 913e430f34eSAlexei Starovoitov EMIT3(add_2mod(0x48, dst_reg, src_reg), 0x85, 914e430f34eSAlexei Starovoitov add_2reg(0xC0, dst_reg, src_reg)); 91562258278SAlexei Starovoitov goto emit_cond_jmp; 91662258278SAlexei Starovoitov 91762258278SAlexei Starovoitov case BPF_JMP | BPF_JSET | BPF_K: 918e430f34eSAlexei Starovoitov /* test dst_reg, imm32 */ 919e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 920e430f34eSAlexei Starovoitov EMIT2_off32(0xF7, add_1reg(0xC0, dst_reg), imm32); 92162258278SAlexei Starovoitov goto emit_cond_jmp; 92262258278SAlexei Starovoitov 92362258278SAlexei Starovoitov case BPF_JMP | BPF_JEQ | BPF_K: 92462258278SAlexei Starovoitov case BPF_JMP | BPF_JNE | BPF_K: 92562258278SAlexei Starovoitov case BPF_JMP | BPF_JGT | BPF_K: 92652afc51eSDaniel Borkmann case BPF_JMP | BPF_JLT | BPF_K: 92762258278SAlexei Starovoitov case BPF_JMP | BPF_JGE | BPF_K: 92852afc51eSDaniel Borkmann case BPF_JMP | BPF_JLE | BPF_K: 92962258278SAlexei Starovoitov case BPF_JMP | BPF_JSGT | BPF_K: 93052afc51eSDaniel Borkmann case BPF_JMP | BPF_JSLT | BPF_K: 93162258278SAlexei Starovoitov case BPF_JMP | BPF_JSGE | BPF_K: 93252afc51eSDaniel Borkmann case BPF_JMP | BPF_JSLE | BPF_K: 933e430f34eSAlexei Starovoitov /* cmp dst_reg, imm8/32 */ 934e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 93562258278SAlexei Starovoitov 936e430f34eSAlexei Starovoitov if (is_imm8(imm32)) 937e430f34eSAlexei Starovoitov EMIT3(0x83, add_1reg(0xF8, dst_reg), imm32); 93862258278SAlexei Starovoitov else 939e430f34eSAlexei Starovoitov EMIT2_off32(0x81, add_1reg(0xF8, dst_reg), imm32); 94062258278SAlexei Starovoitov 94162258278SAlexei Starovoitov emit_cond_jmp: /* convert BPF opcode to x86 */ 94262258278SAlexei Starovoitov switch (BPF_OP(insn->code)) { 94362258278SAlexei Starovoitov case BPF_JEQ: 94462258278SAlexei Starovoitov jmp_cond = X86_JE; 94562258278SAlexei Starovoitov break; 94662258278SAlexei Starovoitov case BPF_JSET: 94762258278SAlexei Starovoitov case BPF_JNE: 94862258278SAlexei Starovoitov jmp_cond = X86_JNE; 94962258278SAlexei Starovoitov break; 95062258278SAlexei Starovoitov case BPF_JGT: 95162258278SAlexei Starovoitov /* GT is unsigned '>', JA in x86 */ 95262258278SAlexei Starovoitov jmp_cond = X86_JA; 95362258278SAlexei Starovoitov break; 95452afc51eSDaniel Borkmann case BPF_JLT: 95552afc51eSDaniel Borkmann /* LT is unsigned '<', JB in x86 */ 95652afc51eSDaniel Borkmann jmp_cond = X86_JB; 95752afc51eSDaniel Borkmann break; 95862258278SAlexei Starovoitov case BPF_JGE: 95962258278SAlexei Starovoitov /* GE is unsigned '>=', JAE in x86 */ 96062258278SAlexei Starovoitov jmp_cond = X86_JAE; 96162258278SAlexei Starovoitov break; 96252afc51eSDaniel Borkmann case BPF_JLE: 96352afc51eSDaniel Borkmann /* LE is unsigned '<=', JBE in x86 */ 96452afc51eSDaniel Borkmann jmp_cond = X86_JBE; 96552afc51eSDaniel Borkmann break; 96662258278SAlexei Starovoitov case BPF_JSGT: 96762258278SAlexei Starovoitov /* signed '>', GT in x86 */ 96862258278SAlexei Starovoitov jmp_cond = X86_JG; 96962258278SAlexei Starovoitov break; 97052afc51eSDaniel Borkmann case BPF_JSLT: 97152afc51eSDaniel Borkmann /* signed '<', LT in x86 */ 97252afc51eSDaniel Borkmann jmp_cond = X86_JL; 97352afc51eSDaniel Borkmann break; 97462258278SAlexei Starovoitov case BPF_JSGE: 97562258278SAlexei Starovoitov /* signed '>=', GE in x86 */ 97662258278SAlexei Starovoitov jmp_cond = X86_JGE; 97762258278SAlexei Starovoitov break; 97852afc51eSDaniel Borkmann case BPF_JSLE: 97952afc51eSDaniel Borkmann /* signed '<=', LE in x86 */ 98052afc51eSDaniel Borkmann jmp_cond = X86_JLE; 98152afc51eSDaniel Borkmann break; 98262258278SAlexei Starovoitov default: /* to silence gcc warning */ 98362258278SAlexei Starovoitov return -EFAULT; 98462258278SAlexei Starovoitov } 98562258278SAlexei Starovoitov jmp_offset = addrs[i + insn->off] - addrs[i]; 98662258278SAlexei Starovoitov if (is_imm8(jmp_offset)) { 98762258278SAlexei Starovoitov EMIT2(jmp_cond, jmp_offset); 98862258278SAlexei Starovoitov } else if (is_simm32(jmp_offset)) { 98962258278SAlexei Starovoitov EMIT2_off32(0x0F, jmp_cond + 0x10, jmp_offset); 9903b58908aSEric Dumazet } else { 99162258278SAlexei Starovoitov pr_err("cond_jmp gen bug %llx\n", jmp_offset); 99262258278SAlexei Starovoitov return -EFAULT; 9933b58908aSEric Dumazet } 99462258278SAlexei Starovoitov 9953b58908aSEric Dumazet break; 99662258278SAlexei Starovoitov 99762258278SAlexei Starovoitov case BPF_JMP | BPF_JA: 99862258278SAlexei Starovoitov jmp_offset = addrs[i + insn->off] - addrs[i]; 99962258278SAlexei Starovoitov if (!jmp_offset) 100062258278SAlexei Starovoitov /* optimize out nop jumps */ 100162258278SAlexei Starovoitov break; 100262258278SAlexei Starovoitov emit_jmp: 100362258278SAlexei Starovoitov if (is_imm8(jmp_offset)) { 100462258278SAlexei Starovoitov EMIT2(0xEB, jmp_offset); 100562258278SAlexei Starovoitov } else if (is_simm32(jmp_offset)) { 100662258278SAlexei Starovoitov EMIT1_off32(0xE9, jmp_offset); 100762258278SAlexei Starovoitov } else { 100862258278SAlexei Starovoitov pr_err("jmp gen bug %llx\n", jmp_offset); 100962258278SAlexei Starovoitov return -EFAULT; 10103b58908aSEric Dumazet } 101162258278SAlexei Starovoitov break; 101262258278SAlexei Starovoitov 101362258278SAlexei Starovoitov case BPF_LD | BPF_IND | BPF_W: 101462258278SAlexei Starovoitov func = sk_load_word; 101562258278SAlexei Starovoitov goto common_load; 101662258278SAlexei Starovoitov case BPF_LD | BPF_ABS | BPF_W: 1017e430f34eSAlexei Starovoitov func = CHOOSE_LOAD_FUNC(imm32, sk_load_word); 1018e0ee9c12SAlexei Starovoitov common_load: 1019e0ee9c12SAlexei Starovoitov ctx->seen_ld_abs = seen_ld_abs = true; 102062258278SAlexei Starovoitov jmp_offset = func - (image + addrs[i]); 102162258278SAlexei Starovoitov if (!func || !is_simm32(jmp_offset)) { 102262258278SAlexei Starovoitov pr_err("unsupported bpf func %d addr %p image %p\n", 1023e430f34eSAlexei Starovoitov imm32, func, image); 102462258278SAlexei Starovoitov return -EINVAL; 102562258278SAlexei Starovoitov } 102662258278SAlexei Starovoitov if (BPF_MODE(insn->code) == BPF_ABS) { 102762258278SAlexei Starovoitov /* mov %esi, imm32 */ 1028e430f34eSAlexei Starovoitov EMIT1_off32(0xBE, imm32); 102962258278SAlexei Starovoitov } else { 1030e430f34eSAlexei Starovoitov /* mov %rsi, src_reg */ 1031e430f34eSAlexei Starovoitov EMIT_mov(BPF_REG_2, src_reg); 1032e430f34eSAlexei Starovoitov if (imm32) { 1033e430f34eSAlexei Starovoitov if (is_imm8(imm32)) 103462258278SAlexei Starovoitov /* add %esi, imm8 */ 1035e430f34eSAlexei Starovoitov EMIT3(0x83, 0xC6, imm32); 103662258278SAlexei Starovoitov else 103762258278SAlexei Starovoitov /* add %esi, imm32 */ 1038e430f34eSAlexei Starovoitov EMIT2_off32(0x81, 0xC6, imm32); 103962258278SAlexei Starovoitov } 104062258278SAlexei Starovoitov } 104162258278SAlexei Starovoitov /* skb pointer is in R6 (%rbx), it will be copied into 104262258278SAlexei Starovoitov * %rdi if skb_copy_bits() call is necessary. 104362258278SAlexei Starovoitov * sk_load_* helpers also use %r10 and %r9d. 104462258278SAlexei Starovoitov * See bpf_jit.S 104562258278SAlexei Starovoitov */ 1046959a7579SDaniel Borkmann if (seen_ax_reg) 1047959a7579SDaniel Borkmann /* r10 = skb->data, mov %r10, off32(%rbx) */ 1048959a7579SDaniel Borkmann EMIT3_off32(0x4c, 0x8b, 0x93, 1049959a7579SDaniel Borkmann offsetof(struct sk_buff, data)); 105062258278SAlexei Starovoitov EMIT1_off32(0xE8, jmp_offset); /* call */ 10510a14842fSEric Dumazet break; 105262258278SAlexei Starovoitov 105362258278SAlexei Starovoitov case BPF_LD | BPF_IND | BPF_H: 105462258278SAlexei Starovoitov func = sk_load_half; 105562258278SAlexei Starovoitov goto common_load; 105662258278SAlexei Starovoitov case BPF_LD | BPF_ABS | BPF_H: 1057e430f34eSAlexei Starovoitov func = CHOOSE_LOAD_FUNC(imm32, sk_load_half); 10580a14842fSEric Dumazet goto common_load; 105962258278SAlexei Starovoitov case BPF_LD | BPF_IND | BPF_B: 106062258278SAlexei Starovoitov func = sk_load_byte; 106162258278SAlexei Starovoitov goto common_load; 106262258278SAlexei Starovoitov case BPF_LD | BPF_ABS | BPF_B: 1063e430f34eSAlexei Starovoitov func = CHOOSE_LOAD_FUNC(imm32, sk_load_byte); 10640a14842fSEric Dumazet goto common_load; 10650a14842fSEric Dumazet 106662258278SAlexei Starovoitov case BPF_JMP | BPF_EXIT: 1067769e0de6SAlexei Starovoitov if (seen_exit) { 106862258278SAlexei Starovoitov jmp_offset = ctx->cleanup_addr - addrs[i]; 106962258278SAlexei Starovoitov goto emit_jmp; 107062258278SAlexei Starovoitov } 1071769e0de6SAlexei Starovoitov seen_exit = true; 107262258278SAlexei Starovoitov /* update cleanup_addr */ 107362258278SAlexei Starovoitov ctx->cleanup_addr = proglen; 1074177366bfSAlexei Starovoitov /* mov rbx, qword ptr [rbp+0] */ 1075177366bfSAlexei Starovoitov EMIT4(0x48, 0x8B, 0x5D, 0); 1076177366bfSAlexei Starovoitov /* mov r13, qword ptr [rbp+8] */ 1077177366bfSAlexei Starovoitov EMIT4(0x4C, 0x8B, 0x6D, 8); 1078177366bfSAlexei Starovoitov /* mov r14, qword ptr [rbp+16] */ 1079177366bfSAlexei Starovoitov EMIT4(0x4C, 0x8B, 0x75, 16); 1080177366bfSAlexei Starovoitov /* mov r15, qword ptr [rbp+24] */ 1081177366bfSAlexei Starovoitov EMIT4(0x4C, 0x8B, 0x7D, 24); 10820a14842fSEric Dumazet 1083177366bfSAlexei Starovoitov /* add rbp, AUX_STACK_SPACE */ 1084177366bfSAlexei Starovoitov EMIT4(0x48, 0x83, 0xC5, AUX_STACK_SPACE); 108562258278SAlexei Starovoitov EMIT1(0xC9); /* leave */ 108662258278SAlexei Starovoitov EMIT1(0xC3); /* ret */ 10870a14842fSEric Dumazet break; 10880a14842fSEric Dumazet 10890a14842fSEric Dumazet default: 109062258278SAlexei Starovoitov /* By design x64 JIT should support all BPF instructions 109162258278SAlexei Starovoitov * This error will be seen if new instruction was added 109262258278SAlexei Starovoitov * to interpreter, but not to JIT 10937ae457c1SAlexei Starovoitov * or if there is junk in bpf_prog 109462258278SAlexei Starovoitov */ 109562258278SAlexei Starovoitov pr_err("bpf_jit: unknown opcode %02x\n", insn->code); 1096f3c2af7bSAlexei Starovoitov return -EINVAL; 10970a14842fSEric Dumazet } 109862258278SAlexei Starovoitov 10990a14842fSEric Dumazet ilen = prog - temp; 1100e0ee9c12SAlexei Starovoitov if (ilen > BPF_MAX_INSN_SIZE) { 11019383191dSDaniel Borkmann pr_err("bpf_jit: fatal insn size error\n"); 1102e0ee9c12SAlexei Starovoitov return -EFAULT; 1103e0ee9c12SAlexei Starovoitov } 1104e0ee9c12SAlexei Starovoitov 11050a14842fSEric Dumazet if (image) { 11060a14842fSEric Dumazet if (unlikely(proglen + ilen > oldproglen)) { 11079383191dSDaniel Borkmann pr_err("bpf_jit: fatal error\n"); 1108f3c2af7bSAlexei Starovoitov return -EFAULT; 11090a14842fSEric Dumazet } 11100a14842fSEric Dumazet memcpy(image + proglen, temp, ilen); 11110a14842fSEric Dumazet } 11120a14842fSEric Dumazet proglen += ilen; 11130a14842fSEric Dumazet addrs[i] = proglen; 11140a14842fSEric Dumazet prog = temp; 11150a14842fSEric Dumazet } 1116f3c2af7bSAlexei Starovoitov return proglen; 1117f3c2af7bSAlexei Starovoitov } 1118f3c2af7bSAlexei Starovoitov 11191c2a088aSAlexei Starovoitov struct x64_jit_data { 11201c2a088aSAlexei Starovoitov struct bpf_binary_header *header; 11211c2a088aSAlexei Starovoitov int *addrs; 11221c2a088aSAlexei Starovoitov u8 *image; 11231c2a088aSAlexei Starovoitov int proglen; 11241c2a088aSAlexei Starovoitov struct jit_context ctx; 11251c2a088aSAlexei Starovoitov }; 11261c2a088aSAlexei Starovoitov 1127d1c55ab5SDaniel Borkmann struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) 112862258278SAlexei Starovoitov { 1129f3c2af7bSAlexei Starovoitov struct bpf_binary_header *header = NULL; 1130959a7579SDaniel Borkmann struct bpf_prog *tmp, *orig_prog = prog; 11311c2a088aSAlexei Starovoitov struct x64_jit_data *jit_data; 1132f3c2af7bSAlexei Starovoitov int proglen, oldproglen = 0; 1133f3c2af7bSAlexei Starovoitov struct jit_context ctx = {}; 1134959a7579SDaniel Borkmann bool tmp_blinded = false; 11351c2a088aSAlexei Starovoitov bool extra_pass = false; 1136f3c2af7bSAlexei Starovoitov u8 *image = NULL; 1137f3c2af7bSAlexei Starovoitov int *addrs; 1138f3c2af7bSAlexei Starovoitov int pass; 1139f3c2af7bSAlexei Starovoitov int i; 1140f3c2af7bSAlexei Starovoitov 114160b58afcSAlexei Starovoitov if (!prog->jit_requested) 1142959a7579SDaniel Borkmann return orig_prog; 1143959a7579SDaniel Borkmann 1144959a7579SDaniel Borkmann tmp = bpf_jit_blind_constants(prog); 1145959a7579SDaniel Borkmann /* If blinding was requested and we failed during blinding, 1146959a7579SDaniel Borkmann * we must fall back to the interpreter. 1147959a7579SDaniel Borkmann */ 1148959a7579SDaniel Borkmann if (IS_ERR(tmp)) 1149959a7579SDaniel Borkmann return orig_prog; 1150959a7579SDaniel Borkmann if (tmp != prog) { 1151959a7579SDaniel Borkmann tmp_blinded = true; 1152959a7579SDaniel Borkmann prog = tmp; 1153959a7579SDaniel Borkmann } 1154f3c2af7bSAlexei Starovoitov 11551c2a088aSAlexei Starovoitov jit_data = prog->aux->jit_data; 11561c2a088aSAlexei Starovoitov if (!jit_data) { 11571c2a088aSAlexei Starovoitov jit_data = kzalloc(sizeof(*jit_data), GFP_KERNEL); 11581c2a088aSAlexei Starovoitov if (!jit_data) { 11591c2a088aSAlexei Starovoitov prog = orig_prog; 11601c2a088aSAlexei Starovoitov goto out; 11611c2a088aSAlexei Starovoitov } 11621c2a088aSAlexei Starovoitov prog->aux->jit_data = jit_data; 11631c2a088aSAlexei Starovoitov } 11641c2a088aSAlexei Starovoitov addrs = jit_data->addrs; 11651c2a088aSAlexei Starovoitov if (addrs) { 11661c2a088aSAlexei Starovoitov ctx = jit_data->ctx; 11671c2a088aSAlexei Starovoitov oldproglen = jit_data->proglen; 11681c2a088aSAlexei Starovoitov image = jit_data->image; 11691c2a088aSAlexei Starovoitov header = jit_data->header; 11701c2a088aSAlexei Starovoitov extra_pass = true; 11711c2a088aSAlexei Starovoitov goto skip_init_addrs; 11721c2a088aSAlexei Starovoitov } 1173f3c2af7bSAlexei Starovoitov addrs = kmalloc(prog->len * sizeof(*addrs), GFP_KERNEL); 1174959a7579SDaniel Borkmann if (!addrs) { 1175959a7579SDaniel Borkmann prog = orig_prog; 11761c2a088aSAlexei Starovoitov goto out_addrs; 1177959a7579SDaniel Borkmann } 1178f3c2af7bSAlexei Starovoitov 1179f3c2af7bSAlexei Starovoitov /* Before first pass, make a rough estimation of addrs[] 1180f3c2af7bSAlexei Starovoitov * each bpf instruction is translated to less than 64 bytes 1181f3c2af7bSAlexei Starovoitov */ 1182f3c2af7bSAlexei Starovoitov for (proglen = 0, i = 0; i < prog->len; i++) { 1183f3c2af7bSAlexei Starovoitov proglen += 64; 1184f3c2af7bSAlexei Starovoitov addrs[i] = proglen; 1185f3c2af7bSAlexei Starovoitov } 1186f3c2af7bSAlexei Starovoitov ctx.cleanup_addr = proglen; 11871c2a088aSAlexei Starovoitov skip_init_addrs: 1188f3c2af7bSAlexei Starovoitov 11893f7352bfSAlexei Starovoitov /* JITed image shrinks with every pass and the loop iterates 11903f7352bfSAlexei Starovoitov * until the image stops shrinking. Very large bpf programs 11913f7352bfSAlexei Starovoitov * may converge on the last pass. In such case do one more 11923f7352bfSAlexei Starovoitov * pass to emit the final image 11933f7352bfSAlexei Starovoitov */ 11943f7352bfSAlexei Starovoitov for (pass = 0; pass < 10 || image; pass++) { 1195f3c2af7bSAlexei Starovoitov proglen = do_jit(prog, addrs, image, oldproglen, &ctx); 1196f3c2af7bSAlexei Starovoitov if (proglen <= 0) { 1197f3c2af7bSAlexei Starovoitov image = NULL; 1198f3c2af7bSAlexei Starovoitov if (header) 1199738cbe72SDaniel Borkmann bpf_jit_binary_free(header); 1200959a7579SDaniel Borkmann prog = orig_prog; 1201959a7579SDaniel Borkmann goto out_addrs; 1202f3c2af7bSAlexei Starovoitov } 12030a14842fSEric Dumazet if (image) { 1204e0ee9c12SAlexei Starovoitov if (proglen != oldproglen) { 1205f3c2af7bSAlexei Starovoitov pr_err("bpf_jit: proglen=%d != oldproglen=%d\n", 1206f3c2af7bSAlexei Starovoitov proglen, oldproglen); 1207959a7579SDaniel Borkmann prog = orig_prog; 1208959a7579SDaniel Borkmann goto out_addrs; 1209e0ee9c12SAlexei Starovoitov } 12100a14842fSEric Dumazet break; 12110a14842fSEric Dumazet } 12120a14842fSEric Dumazet if (proglen == oldproglen) { 1213738cbe72SDaniel Borkmann header = bpf_jit_binary_alloc(proglen, &image, 1214738cbe72SDaniel Borkmann 1, jit_fill_hole); 1215959a7579SDaniel Borkmann if (!header) { 1216959a7579SDaniel Borkmann prog = orig_prog; 1217959a7579SDaniel Borkmann goto out_addrs; 1218959a7579SDaniel Borkmann } 12190a14842fSEric Dumazet } 12200a14842fSEric Dumazet oldproglen = proglen; 12210a14842fSEric Dumazet } 122279617801SDaniel Borkmann 12230a14842fSEric Dumazet if (bpf_jit_enable > 1) 1224485d6511SDaniel Borkmann bpf_jit_dump(prog->len, proglen, pass + 1, image); 12250a14842fSEric Dumazet 12260a14842fSEric Dumazet if (image) { 1227314beb9bSEric Dumazet bpf_flush_icache(header, image + proglen); 12281c2a088aSAlexei Starovoitov if (!prog->is_func || extra_pass) { 12299d876e79SDaniel Borkmann bpf_jit_binary_lock_ro(header); 12301c2a088aSAlexei Starovoitov } else { 12311c2a088aSAlexei Starovoitov jit_data->addrs = addrs; 12321c2a088aSAlexei Starovoitov jit_data->ctx = ctx; 12331c2a088aSAlexei Starovoitov jit_data->proglen = proglen; 12341c2a088aSAlexei Starovoitov jit_data->image = image; 12351c2a088aSAlexei Starovoitov jit_data->header = header; 12361c2a088aSAlexei Starovoitov } 1237f3c2af7bSAlexei Starovoitov prog->bpf_func = (void *)image; 1238a91263d5SDaniel Borkmann prog->jited = 1; 1239783d28ddSMartin KaFai Lau prog->jited_len = proglen; 12409d5ecb09SDaniel Borkmann } else { 12419d5ecb09SDaniel Borkmann prog = orig_prog; 12420a14842fSEric Dumazet } 1243959a7579SDaniel Borkmann 12441c2a088aSAlexei Starovoitov if (!prog->is_func || extra_pass) { 1245959a7579SDaniel Borkmann out_addrs: 12460a14842fSEric Dumazet kfree(addrs); 12471c2a088aSAlexei Starovoitov kfree(jit_data); 12481c2a088aSAlexei Starovoitov prog->aux->jit_data = NULL; 12491c2a088aSAlexei Starovoitov } 1250959a7579SDaniel Borkmann out: 1251959a7579SDaniel Borkmann if (tmp_blinded) 1252959a7579SDaniel Borkmann bpf_jit_prog_release_other(prog, prog == orig_prog ? 1253959a7579SDaniel Borkmann tmp : orig_prog); 1254d1c55ab5SDaniel Borkmann return prog; 12550a14842fSEric Dumazet } 1256