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/moduleloader.h> 120a14842fSEric Dumazet #include <asm/cacheflush.h> 130a14842fSEric Dumazet #include <linux/netdevice.h> 140a14842fSEric Dumazet #include <linux/filter.h> 15855ddb56SEric Dumazet #include <linux/if_vlan.h> 16314beb9bSEric Dumazet #include <linux/random.h> 170a14842fSEric Dumazet 180a14842fSEric Dumazet int bpf_jit_enable __read_mostly; 190a14842fSEric Dumazet 200a14842fSEric Dumazet /* 210a14842fSEric Dumazet * assembly code in arch/x86/net/bpf_jit.S 220a14842fSEric Dumazet */ 2362258278SAlexei Starovoitov extern u8 sk_load_word[], sk_load_half[], sk_load_byte[]; 24a998d434SJan Seiffert extern u8 sk_load_word_positive_offset[], sk_load_half_positive_offset[]; 2562258278SAlexei Starovoitov extern u8 sk_load_byte_positive_offset[]; 26a998d434SJan Seiffert extern u8 sk_load_word_negative_offset[], sk_load_half_negative_offset[]; 2762258278SAlexei Starovoitov extern u8 sk_load_byte_negative_offset[]; 280a14842fSEric Dumazet 290a14842fSEric Dumazet static inline u8 *emit_code(u8 *ptr, u32 bytes, unsigned int len) 300a14842fSEric Dumazet { 310a14842fSEric Dumazet if (len == 1) 320a14842fSEric Dumazet *ptr = bytes; 330a14842fSEric Dumazet else if (len == 2) 340a14842fSEric Dumazet *(u16 *)ptr = bytes; 350a14842fSEric Dumazet else { 360a14842fSEric Dumazet *(u32 *)ptr = bytes; 370a14842fSEric Dumazet barrier(); 380a14842fSEric Dumazet } 390a14842fSEric Dumazet return ptr + len; 400a14842fSEric Dumazet } 410a14842fSEric Dumazet 420a14842fSEric Dumazet #define EMIT(bytes, len) do { prog = emit_code(prog, bytes, len); } while (0) 430a14842fSEric Dumazet 440a14842fSEric Dumazet #define EMIT1(b1) EMIT(b1, 1) 450a14842fSEric Dumazet #define EMIT2(b1, b2) EMIT((b1) + ((b2) << 8), 2) 460a14842fSEric Dumazet #define EMIT3(b1, b2, b3) EMIT((b1) + ((b2) << 8) + ((b3) << 16), 3) 470a14842fSEric Dumazet #define EMIT4(b1, b2, b3, b4) EMIT((b1) + ((b2) << 8) + ((b3) << 16) + ((b4) << 24), 4) 4862258278SAlexei Starovoitov #define EMIT1_off32(b1, off) \ 4962258278SAlexei Starovoitov do {EMIT1(b1); EMIT(off, 4); } while (0) 5062258278SAlexei Starovoitov #define EMIT2_off32(b1, b2, off) \ 5162258278SAlexei Starovoitov do {EMIT2(b1, b2); EMIT(off, 4); } while (0) 5262258278SAlexei Starovoitov #define EMIT3_off32(b1, b2, b3, off) \ 5362258278SAlexei Starovoitov do {EMIT3(b1, b2, b3); EMIT(off, 4); } while (0) 5462258278SAlexei Starovoitov #define EMIT4_off32(b1, b2, b3, b4, off) \ 5562258278SAlexei Starovoitov do {EMIT4(b1, b2, b3, b4); EMIT(off, 4); } while (0) 560a14842fSEric Dumazet 570a14842fSEric Dumazet static inline bool is_imm8(int value) 580a14842fSEric Dumazet { 590a14842fSEric Dumazet return value <= 127 && value >= -128; 600a14842fSEric Dumazet } 610a14842fSEric Dumazet 6262258278SAlexei Starovoitov static inline bool is_simm32(s64 value) 630a14842fSEric Dumazet { 6462258278SAlexei Starovoitov return value == (s64) (s32) value; 650a14842fSEric Dumazet } 660a14842fSEric Dumazet 67e430f34eSAlexei Starovoitov /* mov dst, src */ 68e430f34eSAlexei Starovoitov #define EMIT_mov(DST, SRC) \ 69e430f34eSAlexei Starovoitov do {if (DST != SRC) \ 70e430f34eSAlexei Starovoitov EMIT3(add_2mod(0x48, DST, SRC), 0x89, add_2reg(0xC0, DST, SRC)); \ 710a14842fSEric Dumazet } while (0) 720a14842fSEric Dumazet 7362258278SAlexei Starovoitov static int bpf_size_to_x86_bytes(int bpf_size) 7462258278SAlexei Starovoitov { 7562258278SAlexei Starovoitov if (bpf_size == BPF_W) 7662258278SAlexei Starovoitov return 4; 7762258278SAlexei Starovoitov else if (bpf_size == BPF_H) 7862258278SAlexei Starovoitov return 2; 7962258278SAlexei Starovoitov else if (bpf_size == BPF_B) 8062258278SAlexei Starovoitov return 1; 8162258278SAlexei Starovoitov else if (bpf_size == BPF_DW) 8262258278SAlexei Starovoitov return 4; /* imm32 */ 8362258278SAlexei Starovoitov else 8462258278SAlexei Starovoitov return 0; 8562258278SAlexei Starovoitov } 8662258278SAlexei Starovoitov 870a14842fSEric Dumazet /* list of x86 cond jumps opcodes (. + s8) 880a14842fSEric Dumazet * Add 0x10 (and an extra 0x0f) to generate far jumps (. + s32) 890a14842fSEric Dumazet */ 900a14842fSEric Dumazet #define X86_JB 0x72 910a14842fSEric Dumazet #define X86_JAE 0x73 920a14842fSEric Dumazet #define X86_JE 0x74 930a14842fSEric Dumazet #define X86_JNE 0x75 940a14842fSEric Dumazet #define X86_JBE 0x76 950a14842fSEric Dumazet #define X86_JA 0x77 9662258278SAlexei Starovoitov #define X86_JGE 0x7D 9762258278SAlexei Starovoitov #define X86_JG 0x7F 980a14842fSEric Dumazet 990a14842fSEric Dumazet static inline void bpf_flush_icache(void *start, void *end) 1000a14842fSEric Dumazet { 1010a14842fSEric Dumazet mm_segment_t old_fs = get_fs(); 1020a14842fSEric Dumazet 1030a14842fSEric Dumazet set_fs(KERNEL_DS); 1040a14842fSEric Dumazet smp_wmb(); 1050a14842fSEric Dumazet flush_icache_range((unsigned long)start, (unsigned long)end); 1060a14842fSEric Dumazet set_fs(old_fs); 1070a14842fSEric Dumazet } 1080a14842fSEric Dumazet 109a998d434SJan Seiffert #define CHOOSE_LOAD_FUNC(K, func) \ 110a998d434SJan Seiffert ((int)K < 0 ? ((int)K >= SKF_LL_OFF ? func##_negative_offset : func) : func##_positive_offset) 1110a14842fSEric Dumazet 112314beb9bSEric Dumazet struct bpf_binary_header { 113314beb9bSEric Dumazet unsigned int pages; 114314beb9bSEric Dumazet /* Note : for security reasons, bpf code will follow a randomly 115314beb9bSEric Dumazet * sized amount of int3 instructions 116314beb9bSEric Dumazet */ 117314beb9bSEric Dumazet u8 image[]; 118314beb9bSEric Dumazet }; 119314beb9bSEric Dumazet 120314beb9bSEric Dumazet static struct bpf_binary_header *bpf_alloc_binary(unsigned int proglen, 121314beb9bSEric Dumazet u8 **image_ptr) 122314beb9bSEric Dumazet { 123314beb9bSEric Dumazet unsigned int sz, hole; 124314beb9bSEric Dumazet struct bpf_binary_header *header; 125314beb9bSEric Dumazet 126314beb9bSEric Dumazet /* Most of BPF filters are really small, 127314beb9bSEric Dumazet * but if some of them fill a page, allow at least 128314beb9bSEric Dumazet * 128 extra bytes to insert a random section of int3 129314beb9bSEric Dumazet */ 130314beb9bSEric Dumazet sz = round_up(proglen + sizeof(*header) + 128, PAGE_SIZE); 131314beb9bSEric Dumazet header = module_alloc(sz); 132314beb9bSEric Dumazet if (!header) 133314beb9bSEric Dumazet return NULL; 134314beb9bSEric Dumazet 135314beb9bSEric Dumazet memset(header, 0xcc, sz); /* fill whole space with int3 instructions */ 136314beb9bSEric Dumazet 137314beb9bSEric Dumazet header->pages = sz / PAGE_SIZE; 138773cd38fSAlexei Starovoitov hole = min(sz - (proglen + sizeof(*header)), PAGE_SIZE - sizeof(*header)); 139314beb9bSEric Dumazet 140314beb9bSEric Dumazet /* insert a random number of int3 instructions before BPF code */ 141314beb9bSEric Dumazet *image_ptr = &header->image[prandom_u32() % hole]; 142314beb9bSEric Dumazet return header; 143314beb9bSEric Dumazet } 144314beb9bSEric Dumazet 14562258278SAlexei Starovoitov /* pick a register outside of BPF range for JIT internal work */ 14662258278SAlexei Starovoitov #define AUX_REG (MAX_BPF_REG + 1) 14762258278SAlexei Starovoitov 14862258278SAlexei Starovoitov /* the following table maps BPF registers to x64 registers. 14962258278SAlexei Starovoitov * x64 register r12 is unused, since if used as base address register 15062258278SAlexei Starovoitov * in load/store instructions, it always needs an extra byte of encoding 15162258278SAlexei Starovoitov */ 15262258278SAlexei Starovoitov static const int reg2hex[] = { 15362258278SAlexei Starovoitov [BPF_REG_0] = 0, /* rax */ 15462258278SAlexei Starovoitov [BPF_REG_1] = 7, /* rdi */ 15562258278SAlexei Starovoitov [BPF_REG_2] = 6, /* rsi */ 15662258278SAlexei Starovoitov [BPF_REG_3] = 2, /* rdx */ 15762258278SAlexei Starovoitov [BPF_REG_4] = 1, /* rcx */ 15862258278SAlexei Starovoitov [BPF_REG_5] = 0, /* r8 */ 15962258278SAlexei Starovoitov [BPF_REG_6] = 3, /* rbx callee saved */ 16062258278SAlexei Starovoitov [BPF_REG_7] = 5, /* r13 callee saved */ 16162258278SAlexei Starovoitov [BPF_REG_8] = 6, /* r14 callee saved */ 16262258278SAlexei Starovoitov [BPF_REG_9] = 7, /* r15 callee saved */ 16362258278SAlexei Starovoitov [BPF_REG_FP] = 5, /* rbp readonly */ 16462258278SAlexei Starovoitov [AUX_REG] = 3, /* r11 temp register */ 16562258278SAlexei Starovoitov }; 16662258278SAlexei Starovoitov 16762258278SAlexei Starovoitov /* is_ereg() == true if BPF register 'reg' maps to x64 r8..r15 16862258278SAlexei Starovoitov * which need extra byte of encoding. 16962258278SAlexei Starovoitov * rax,rcx,...,rbp have simpler encoding 17062258278SAlexei Starovoitov */ 17162258278SAlexei Starovoitov static inline bool is_ereg(u32 reg) 17262258278SAlexei Starovoitov { 17362258278SAlexei Starovoitov if (reg == BPF_REG_5 || reg == AUX_REG || 17462258278SAlexei Starovoitov (reg >= BPF_REG_7 && reg <= BPF_REG_9)) 17562258278SAlexei Starovoitov return true; 17662258278SAlexei Starovoitov else 17762258278SAlexei Starovoitov return false; 17862258278SAlexei Starovoitov } 17962258278SAlexei Starovoitov 18062258278SAlexei Starovoitov /* add modifiers if 'reg' maps to x64 registers r8..r15 */ 18162258278SAlexei Starovoitov static inline u8 add_1mod(u8 byte, u32 reg) 18262258278SAlexei Starovoitov { 18362258278SAlexei Starovoitov if (is_ereg(reg)) 18462258278SAlexei Starovoitov byte |= 1; 18562258278SAlexei Starovoitov return byte; 18662258278SAlexei Starovoitov } 18762258278SAlexei Starovoitov 18862258278SAlexei Starovoitov static inline u8 add_2mod(u8 byte, u32 r1, u32 r2) 18962258278SAlexei Starovoitov { 19062258278SAlexei Starovoitov if (is_ereg(r1)) 19162258278SAlexei Starovoitov byte |= 1; 19262258278SAlexei Starovoitov if (is_ereg(r2)) 19362258278SAlexei Starovoitov byte |= 4; 19462258278SAlexei Starovoitov return byte; 19562258278SAlexei Starovoitov } 19662258278SAlexei Starovoitov 197e430f34eSAlexei Starovoitov /* encode 'dst_reg' register into x64 opcode 'byte' */ 198e430f34eSAlexei Starovoitov static inline u8 add_1reg(u8 byte, u32 dst_reg) 19962258278SAlexei Starovoitov { 200e430f34eSAlexei Starovoitov return byte + reg2hex[dst_reg]; 20162258278SAlexei Starovoitov } 20262258278SAlexei Starovoitov 203e430f34eSAlexei Starovoitov /* encode 'dst_reg' and 'src_reg' registers into x64 opcode 'byte' */ 204e430f34eSAlexei Starovoitov static inline u8 add_2reg(u8 byte, u32 dst_reg, u32 src_reg) 20562258278SAlexei Starovoitov { 206e430f34eSAlexei Starovoitov return byte + reg2hex[dst_reg] + (reg2hex[src_reg] << 3); 20762258278SAlexei Starovoitov } 20862258278SAlexei Starovoitov 209f3c2af7bSAlexei Starovoitov struct jit_context { 210f3c2af7bSAlexei Starovoitov unsigned int cleanup_addr; /* epilogue code offset */ 21162258278SAlexei Starovoitov bool seen_ld_abs; 212f3c2af7bSAlexei Starovoitov }; 213f3c2af7bSAlexei Starovoitov 214f3c2af7bSAlexei Starovoitov static int do_jit(struct sk_filter *bpf_prog, int *addrs, u8 *image, 215f3c2af7bSAlexei Starovoitov int oldproglen, struct jit_context *ctx) 2160a14842fSEric Dumazet { 2172695fb55SAlexei Starovoitov struct bpf_insn *insn = bpf_prog->insnsi; 21862258278SAlexei Starovoitov int insn_cnt = bpf_prog->len; 2190a14842fSEric Dumazet u8 temp[64]; 22062258278SAlexei Starovoitov int i; 22162258278SAlexei Starovoitov int proglen = 0; 22262258278SAlexei Starovoitov u8 *prog = temp; 22362258278SAlexei Starovoitov int stacksize = MAX_BPF_STACK + 22462258278SAlexei Starovoitov 32 /* space for rbx, r13, r14, r15 */ + 22562258278SAlexei Starovoitov 8 /* space for skb_copy_bits() buffer */; 2260a14842fSEric Dumazet 22762258278SAlexei Starovoitov EMIT1(0x55); /* push rbp */ 22862258278SAlexei Starovoitov EMIT3(0x48, 0x89, 0xE5); /* mov rbp,rsp */ 2290a14842fSEric Dumazet 23062258278SAlexei Starovoitov /* sub rsp, stacksize */ 23162258278SAlexei Starovoitov EMIT3_off32(0x48, 0x81, 0xEC, stacksize); 2320a14842fSEric Dumazet 23362258278SAlexei Starovoitov /* all classic BPF filters use R6(rbx) save it */ 23462258278SAlexei Starovoitov 23562258278SAlexei Starovoitov /* mov qword ptr [rbp-X],rbx */ 23662258278SAlexei Starovoitov EMIT3_off32(0x48, 0x89, 0x9D, -stacksize); 23762258278SAlexei Starovoitov 2388fb575caSAlexei Starovoitov /* bpf_convert_filter() maps classic BPF register X to R7 and uses R8 23962258278SAlexei Starovoitov * as temporary, so all tcpdump filters need to spill/fill R7(r13) and 24062258278SAlexei Starovoitov * R8(r14). R9(r15) spill could be made conditional, but there is only 24162258278SAlexei Starovoitov * one 'bpf_error' return path out of helper functions inside bpf_jit.S 24262258278SAlexei Starovoitov * The overhead of extra spill is negligible for any filter other 24362258278SAlexei Starovoitov * than synthetic ones. Therefore not worth adding complexity. 2440a14842fSEric Dumazet */ 24562258278SAlexei Starovoitov 24662258278SAlexei Starovoitov /* mov qword ptr [rbp-X],r13 */ 24762258278SAlexei Starovoitov EMIT3_off32(0x4C, 0x89, 0xAD, -stacksize + 8); 24862258278SAlexei Starovoitov /* mov qword ptr [rbp-X],r14 */ 24962258278SAlexei Starovoitov EMIT3_off32(0x4C, 0x89, 0xB5, -stacksize + 16); 25062258278SAlexei Starovoitov /* mov qword ptr [rbp-X],r15 */ 25162258278SAlexei Starovoitov EMIT3_off32(0x4C, 0x89, 0xBD, -stacksize + 24); 25262258278SAlexei Starovoitov 25362258278SAlexei Starovoitov /* clear A and X registers */ 25462258278SAlexei Starovoitov EMIT2(0x31, 0xc0); /* xor eax, eax */ 25562258278SAlexei Starovoitov EMIT3(0x4D, 0x31, 0xED); /* xor r13, r13 */ 25662258278SAlexei Starovoitov 25762258278SAlexei Starovoitov if (ctx->seen_ld_abs) { 25862258278SAlexei Starovoitov /* r9d : skb->len - skb->data_len (headlen) 25962258278SAlexei Starovoitov * r10 : skb->data 26062258278SAlexei Starovoitov */ 26162258278SAlexei Starovoitov if (is_imm8(offsetof(struct sk_buff, len))) 26262258278SAlexei Starovoitov /* mov %r9d, off8(%rdi) */ 26362258278SAlexei Starovoitov EMIT4(0x44, 0x8b, 0x4f, 26462258278SAlexei Starovoitov offsetof(struct sk_buff, len)); 26562258278SAlexei Starovoitov else 26662258278SAlexei Starovoitov /* mov %r9d, off32(%rdi) */ 26762258278SAlexei Starovoitov EMIT3_off32(0x44, 0x8b, 0x8f, 26862258278SAlexei Starovoitov offsetof(struct sk_buff, len)); 26962258278SAlexei Starovoitov 2700a14842fSEric Dumazet if (is_imm8(offsetof(struct sk_buff, data_len))) 27162258278SAlexei Starovoitov /* sub %r9d, off8(%rdi) */ 27262258278SAlexei Starovoitov EMIT4(0x44, 0x2b, 0x4f, 27362258278SAlexei Starovoitov offsetof(struct sk_buff, data_len)); 27462258278SAlexei Starovoitov else 27562258278SAlexei Starovoitov EMIT3_off32(0x44, 0x2b, 0x8f, 27662258278SAlexei Starovoitov offsetof(struct sk_buff, data_len)); 2770a14842fSEric Dumazet 2780a14842fSEric Dumazet if (is_imm8(offsetof(struct sk_buff, data))) 27962258278SAlexei Starovoitov /* mov %r10, off8(%rdi) */ 28062258278SAlexei Starovoitov EMIT4(0x4c, 0x8b, 0x57, 28162258278SAlexei Starovoitov offsetof(struct sk_buff, data)); 2820a14842fSEric Dumazet else 28362258278SAlexei Starovoitov /* mov %r10, off32(%rdi) */ 28462258278SAlexei Starovoitov EMIT3_off32(0x4c, 0x8b, 0x97, 28562258278SAlexei Starovoitov offsetof(struct sk_buff, data)); 2860a14842fSEric Dumazet } 28762258278SAlexei Starovoitov 28862258278SAlexei Starovoitov for (i = 0; i < insn_cnt; i++, insn++) { 289e430f34eSAlexei Starovoitov const s32 imm32 = insn->imm; 290e430f34eSAlexei Starovoitov u32 dst_reg = insn->dst_reg; 291e430f34eSAlexei Starovoitov u32 src_reg = insn->src_reg; 29262258278SAlexei Starovoitov u8 b1 = 0, b2 = 0, b3 = 0; 29362258278SAlexei Starovoitov s64 jmp_offset; 29462258278SAlexei Starovoitov u8 jmp_cond; 29562258278SAlexei Starovoitov int ilen; 29662258278SAlexei Starovoitov u8 *func; 29762258278SAlexei Starovoitov 29862258278SAlexei Starovoitov switch (insn->code) { 29962258278SAlexei Starovoitov /* ALU */ 30062258278SAlexei Starovoitov case BPF_ALU | BPF_ADD | BPF_X: 30162258278SAlexei Starovoitov case BPF_ALU | BPF_SUB | BPF_X: 30262258278SAlexei Starovoitov case BPF_ALU | BPF_AND | BPF_X: 30362258278SAlexei Starovoitov case BPF_ALU | BPF_OR | BPF_X: 30462258278SAlexei Starovoitov case BPF_ALU | BPF_XOR | BPF_X: 30562258278SAlexei Starovoitov case BPF_ALU64 | BPF_ADD | BPF_X: 30662258278SAlexei Starovoitov case BPF_ALU64 | BPF_SUB | BPF_X: 30762258278SAlexei Starovoitov case BPF_ALU64 | BPF_AND | BPF_X: 30862258278SAlexei Starovoitov case BPF_ALU64 | BPF_OR | BPF_X: 30962258278SAlexei Starovoitov case BPF_ALU64 | BPF_XOR | BPF_X: 31062258278SAlexei Starovoitov switch (BPF_OP(insn->code)) { 31162258278SAlexei Starovoitov case BPF_ADD: b2 = 0x01; break; 31262258278SAlexei Starovoitov case BPF_SUB: b2 = 0x29; break; 31362258278SAlexei Starovoitov case BPF_AND: b2 = 0x21; break; 31462258278SAlexei Starovoitov case BPF_OR: b2 = 0x09; break; 31562258278SAlexei Starovoitov case BPF_XOR: b2 = 0x31; break; 31662258278SAlexei Starovoitov } 31762258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 318e430f34eSAlexei Starovoitov EMIT1(add_2mod(0x48, dst_reg, src_reg)); 319e430f34eSAlexei Starovoitov else if (is_ereg(dst_reg) || is_ereg(src_reg)) 320e430f34eSAlexei Starovoitov EMIT1(add_2mod(0x40, dst_reg, src_reg)); 321e430f34eSAlexei Starovoitov EMIT2(b2, add_2reg(0xC0, dst_reg, src_reg)); 3220a14842fSEric Dumazet break; 32362258278SAlexei Starovoitov 324e430f34eSAlexei Starovoitov /* mov dst, src */ 32562258278SAlexei Starovoitov case BPF_ALU64 | BPF_MOV | BPF_X: 326e430f34eSAlexei Starovoitov EMIT_mov(dst_reg, src_reg); 32762258278SAlexei Starovoitov break; 32862258278SAlexei Starovoitov 329e430f34eSAlexei Starovoitov /* mov32 dst, src */ 33062258278SAlexei Starovoitov case BPF_ALU | BPF_MOV | BPF_X: 331e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 332e430f34eSAlexei Starovoitov EMIT1(add_2mod(0x40, dst_reg, src_reg)); 333e430f34eSAlexei Starovoitov EMIT2(0x89, add_2reg(0xC0, dst_reg, src_reg)); 33462258278SAlexei Starovoitov break; 33562258278SAlexei Starovoitov 336e430f34eSAlexei Starovoitov /* neg dst */ 33762258278SAlexei Starovoitov case BPF_ALU | BPF_NEG: 33862258278SAlexei Starovoitov case BPF_ALU64 | BPF_NEG: 33962258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 340e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 341e430f34eSAlexei Starovoitov else if (is_ereg(dst_reg)) 342e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x40, dst_reg)); 343e430f34eSAlexei Starovoitov EMIT2(0xF7, add_1reg(0xD8, dst_reg)); 34462258278SAlexei Starovoitov break; 34562258278SAlexei Starovoitov 34662258278SAlexei Starovoitov case BPF_ALU | BPF_ADD | BPF_K: 34762258278SAlexei Starovoitov case BPF_ALU | BPF_SUB | BPF_K: 34862258278SAlexei Starovoitov case BPF_ALU | BPF_AND | BPF_K: 34962258278SAlexei Starovoitov case BPF_ALU | BPF_OR | BPF_K: 35062258278SAlexei Starovoitov case BPF_ALU | BPF_XOR | BPF_K: 35162258278SAlexei Starovoitov case BPF_ALU64 | BPF_ADD | BPF_K: 35262258278SAlexei Starovoitov case BPF_ALU64 | BPF_SUB | BPF_K: 35362258278SAlexei Starovoitov case BPF_ALU64 | BPF_AND | BPF_K: 35462258278SAlexei Starovoitov case BPF_ALU64 | BPF_OR | BPF_K: 35562258278SAlexei Starovoitov case BPF_ALU64 | BPF_XOR | BPF_K: 35662258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 357e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 358e430f34eSAlexei Starovoitov else if (is_ereg(dst_reg)) 359e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x40, dst_reg)); 36062258278SAlexei Starovoitov 36162258278SAlexei Starovoitov switch (BPF_OP(insn->code)) { 36262258278SAlexei Starovoitov case BPF_ADD: b3 = 0xC0; break; 36362258278SAlexei Starovoitov case BPF_SUB: b3 = 0xE8; break; 36462258278SAlexei Starovoitov case BPF_AND: b3 = 0xE0; break; 36562258278SAlexei Starovoitov case BPF_OR: b3 = 0xC8; break; 36662258278SAlexei Starovoitov case BPF_XOR: b3 = 0xF0; break; 36762258278SAlexei Starovoitov } 36862258278SAlexei Starovoitov 369e430f34eSAlexei Starovoitov if (is_imm8(imm32)) 370e430f34eSAlexei Starovoitov EMIT3(0x83, add_1reg(b3, dst_reg), imm32); 37162258278SAlexei Starovoitov else 372e430f34eSAlexei Starovoitov EMIT2_off32(0x81, add_1reg(b3, dst_reg), imm32); 37362258278SAlexei Starovoitov break; 37462258278SAlexei Starovoitov 37562258278SAlexei Starovoitov case BPF_ALU64 | BPF_MOV | BPF_K: 37662258278SAlexei Starovoitov /* optimization: if imm32 is positive, 37762258278SAlexei Starovoitov * use 'mov eax, imm32' (which zero-extends imm32) 37862258278SAlexei Starovoitov * to save 2 bytes 379d00a9dd2SEric Dumazet */ 380e430f34eSAlexei Starovoitov if (imm32 < 0) { 38162258278SAlexei Starovoitov /* 'mov rax, imm32' sign extends imm32 */ 382e430f34eSAlexei Starovoitov b1 = add_1mod(0x48, dst_reg); 38362258278SAlexei Starovoitov b2 = 0xC7; 38462258278SAlexei Starovoitov b3 = 0xC0; 385e430f34eSAlexei Starovoitov EMIT3_off32(b1, b2, add_1reg(b3, dst_reg), imm32); 386aee636c4SEric Dumazet break; 387aee636c4SEric Dumazet } 3883b58908aSEric Dumazet 38962258278SAlexei Starovoitov case BPF_ALU | BPF_MOV | BPF_K: 39062258278SAlexei Starovoitov /* mov %eax, imm32 */ 391e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 392e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x40, dst_reg)); 393e430f34eSAlexei Starovoitov EMIT1_off32(add_1reg(0xB8, dst_reg), imm32); 39462258278SAlexei Starovoitov break; 39562258278SAlexei Starovoitov 396e430f34eSAlexei Starovoitov /* dst %= src, dst /= src, dst %= imm32, dst /= imm32 */ 39762258278SAlexei Starovoitov case BPF_ALU | BPF_MOD | BPF_X: 39862258278SAlexei Starovoitov case BPF_ALU | BPF_DIV | BPF_X: 39962258278SAlexei Starovoitov case BPF_ALU | BPF_MOD | BPF_K: 40062258278SAlexei Starovoitov case BPF_ALU | BPF_DIV | BPF_K: 40162258278SAlexei Starovoitov case BPF_ALU64 | BPF_MOD | BPF_X: 40262258278SAlexei Starovoitov case BPF_ALU64 | BPF_DIV | BPF_X: 40362258278SAlexei Starovoitov case BPF_ALU64 | BPF_MOD | BPF_K: 40462258278SAlexei Starovoitov case BPF_ALU64 | BPF_DIV | BPF_K: 40562258278SAlexei Starovoitov EMIT1(0x50); /* push rax */ 40662258278SAlexei Starovoitov EMIT1(0x52); /* push rdx */ 40762258278SAlexei Starovoitov 40862258278SAlexei Starovoitov if (BPF_SRC(insn->code) == BPF_X) 409e430f34eSAlexei Starovoitov /* mov r11, src_reg */ 410e430f34eSAlexei Starovoitov EMIT_mov(AUX_REG, src_reg); 41162258278SAlexei Starovoitov else 412e430f34eSAlexei Starovoitov /* mov r11, imm32 */ 413e430f34eSAlexei Starovoitov EMIT3_off32(0x49, 0xC7, 0xC3, imm32); 41462258278SAlexei Starovoitov 415e430f34eSAlexei Starovoitov /* mov rax, dst_reg */ 416e430f34eSAlexei Starovoitov EMIT_mov(BPF_REG_0, dst_reg); 41762258278SAlexei Starovoitov 41862258278SAlexei Starovoitov /* xor edx, edx 41962258278SAlexei Starovoitov * equivalent to 'xor rdx, rdx', but one byte less 42062258278SAlexei Starovoitov */ 42162258278SAlexei Starovoitov EMIT2(0x31, 0xd2); 42262258278SAlexei Starovoitov 42362258278SAlexei Starovoitov if (BPF_SRC(insn->code) == BPF_X) { 424e430f34eSAlexei Starovoitov /* if (src_reg == 0) return 0 */ 42562258278SAlexei Starovoitov 42662258278SAlexei Starovoitov /* cmp r11, 0 */ 42762258278SAlexei Starovoitov EMIT4(0x49, 0x83, 0xFB, 0x00); 42862258278SAlexei Starovoitov 42962258278SAlexei Starovoitov /* jne .+9 (skip over pop, pop, xor and jmp) */ 43062258278SAlexei Starovoitov EMIT2(X86_JNE, 1 + 1 + 2 + 5); 43162258278SAlexei Starovoitov EMIT1(0x5A); /* pop rdx */ 43262258278SAlexei Starovoitov EMIT1(0x58); /* pop rax */ 43362258278SAlexei Starovoitov EMIT2(0x31, 0xc0); /* xor eax, eax */ 43462258278SAlexei Starovoitov 43562258278SAlexei Starovoitov /* jmp cleanup_addr 43662258278SAlexei Starovoitov * addrs[i] - 11, because there are 11 bytes 43762258278SAlexei Starovoitov * after this insn: div, mov, pop, pop, mov 43862258278SAlexei Starovoitov */ 43962258278SAlexei Starovoitov jmp_offset = ctx->cleanup_addr - (addrs[i] - 11); 44062258278SAlexei Starovoitov EMIT1_off32(0xE9, jmp_offset); 44162258278SAlexei Starovoitov } 44262258278SAlexei Starovoitov 44362258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 44462258278SAlexei Starovoitov /* div r11 */ 44562258278SAlexei Starovoitov EMIT3(0x49, 0xF7, 0xF3); 44662258278SAlexei Starovoitov else 44762258278SAlexei Starovoitov /* div r11d */ 44862258278SAlexei Starovoitov EMIT3(0x41, 0xF7, 0xF3); 44962258278SAlexei Starovoitov 45062258278SAlexei Starovoitov if (BPF_OP(insn->code) == BPF_MOD) 45162258278SAlexei Starovoitov /* mov r11, rdx */ 45262258278SAlexei Starovoitov EMIT3(0x49, 0x89, 0xD3); 45362258278SAlexei Starovoitov else 45462258278SAlexei Starovoitov /* mov r11, rax */ 45562258278SAlexei Starovoitov EMIT3(0x49, 0x89, 0xC3); 45662258278SAlexei Starovoitov 45762258278SAlexei Starovoitov EMIT1(0x5A); /* pop rdx */ 45862258278SAlexei Starovoitov EMIT1(0x58); /* pop rax */ 45962258278SAlexei Starovoitov 460e430f34eSAlexei Starovoitov /* mov dst_reg, r11 */ 461e430f34eSAlexei Starovoitov EMIT_mov(dst_reg, AUX_REG); 46262258278SAlexei Starovoitov break; 46362258278SAlexei Starovoitov 46462258278SAlexei Starovoitov case BPF_ALU | BPF_MUL | BPF_K: 46562258278SAlexei Starovoitov case BPF_ALU | BPF_MUL | BPF_X: 46662258278SAlexei Starovoitov case BPF_ALU64 | BPF_MUL | BPF_K: 46762258278SAlexei Starovoitov case BPF_ALU64 | BPF_MUL | BPF_X: 46862258278SAlexei Starovoitov EMIT1(0x50); /* push rax */ 46962258278SAlexei Starovoitov EMIT1(0x52); /* push rdx */ 47062258278SAlexei Starovoitov 471e430f34eSAlexei Starovoitov /* mov r11, dst_reg */ 472e430f34eSAlexei Starovoitov EMIT_mov(AUX_REG, dst_reg); 47362258278SAlexei Starovoitov 47462258278SAlexei Starovoitov if (BPF_SRC(insn->code) == BPF_X) 475e430f34eSAlexei Starovoitov /* mov rax, src_reg */ 476e430f34eSAlexei Starovoitov EMIT_mov(BPF_REG_0, src_reg); 47762258278SAlexei Starovoitov else 478e430f34eSAlexei Starovoitov /* mov rax, imm32 */ 479e430f34eSAlexei Starovoitov EMIT3_off32(0x48, 0xC7, 0xC0, imm32); 48062258278SAlexei Starovoitov 48162258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 48262258278SAlexei Starovoitov EMIT1(add_1mod(0x48, AUX_REG)); 48362258278SAlexei Starovoitov else if (is_ereg(AUX_REG)) 48462258278SAlexei Starovoitov EMIT1(add_1mod(0x40, AUX_REG)); 48562258278SAlexei Starovoitov /* mul(q) r11 */ 48662258278SAlexei Starovoitov EMIT2(0xF7, add_1reg(0xE0, AUX_REG)); 48762258278SAlexei Starovoitov 48862258278SAlexei Starovoitov /* mov r11, rax */ 48962258278SAlexei Starovoitov EMIT_mov(AUX_REG, BPF_REG_0); 49062258278SAlexei Starovoitov 49162258278SAlexei Starovoitov EMIT1(0x5A); /* pop rdx */ 49262258278SAlexei Starovoitov EMIT1(0x58); /* pop rax */ 49362258278SAlexei Starovoitov 494e430f34eSAlexei Starovoitov /* mov dst_reg, r11 */ 495e430f34eSAlexei Starovoitov EMIT_mov(dst_reg, AUX_REG); 49662258278SAlexei Starovoitov break; 49762258278SAlexei Starovoitov 49862258278SAlexei Starovoitov /* shifts */ 49962258278SAlexei Starovoitov case BPF_ALU | BPF_LSH | BPF_K: 50062258278SAlexei Starovoitov case BPF_ALU | BPF_RSH | BPF_K: 50162258278SAlexei Starovoitov case BPF_ALU | BPF_ARSH | BPF_K: 50262258278SAlexei Starovoitov case BPF_ALU64 | BPF_LSH | BPF_K: 50362258278SAlexei Starovoitov case BPF_ALU64 | BPF_RSH | BPF_K: 50462258278SAlexei Starovoitov case BPF_ALU64 | BPF_ARSH | BPF_K: 50562258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 506e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 507e430f34eSAlexei Starovoitov else if (is_ereg(dst_reg)) 508e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x40, dst_reg)); 50962258278SAlexei Starovoitov 51062258278SAlexei Starovoitov switch (BPF_OP(insn->code)) { 51162258278SAlexei Starovoitov case BPF_LSH: b3 = 0xE0; break; 51262258278SAlexei Starovoitov case BPF_RSH: b3 = 0xE8; break; 51362258278SAlexei Starovoitov case BPF_ARSH: b3 = 0xF8; break; 51462258278SAlexei Starovoitov } 515e430f34eSAlexei Starovoitov EMIT3(0xC1, add_1reg(b3, dst_reg), imm32); 51662258278SAlexei Starovoitov break; 51762258278SAlexei Starovoitov 51862258278SAlexei Starovoitov case BPF_ALU | BPF_END | BPF_FROM_BE: 519e430f34eSAlexei Starovoitov switch (imm32) { 52062258278SAlexei Starovoitov case 16: 52162258278SAlexei Starovoitov /* emit 'ror %ax, 8' to swap lower 2 bytes */ 52262258278SAlexei Starovoitov EMIT1(0x66); 523e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 52462258278SAlexei Starovoitov EMIT1(0x41); 525e430f34eSAlexei Starovoitov EMIT3(0xC1, add_1reg(0xC8, dst_reg), 8); 52662258278SAlexei Starovoitov break; 52762258278SAlexei Starovoitov case 32: 52862258278SAlexei Starovoitov /* emit 'bswap eax' to swap lower 4 bytes */ 529e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 53062258278SAlexei Starovoitov EMIT2(0x41, 0x0F); 53162258278SAlexei Starovoitov else 53262258278SAlexei Starovoitov EMIT1(0x0F); 533e430f34eSAlexei Starovoitov EMIT1(add_1reg(0xC8, dst_reg)); 53462258278SAlexei Starovoitov break; 53562258278SAlexei Starovoitov case 64: 53662258278SAlexei Starovoitov /* emit 'bswap rax' to swap 8 bytes */ 537e430f34eSAlexei Starovoitov EMIT3(add_1mod(0x48, dst_reg), 0x0F, 538e430f34eSAlexei Starovoitov add_1reg(0xC8, dst_reg)); 53962258278SAlexei Starovoitov break; 54062258278SAlexei Starovoitov } 54162258278SAlexei Starovoitov break; 54262258278SAlexei Starovoitov 54362258278SAlexei Starovoitov case BPF_ALU | BPF_END | BPF_FROM_LE: 54462258278SAlexei Starovoitov break; 54562258278SAlexei Starovoitov 546e430f34eSAlexei Starovoitov /* ST: *(u8*)(dst_reg + off) = imm */ 54762258278SAlexei Starovoitov case BPF_ST | BPF_MEM | BPF_B: 548e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 54962258278SAlexei Starovoitov EMIT2(0x41, 0xC6); 55062258278SAlexei Starovoitov else 55162258278SAlexei Starovoitov EMIT1(0xC6); 55262258278SAlexei Starovoitov goto st; 55362258278SAlexei Starovoitov case BPF_ST | BPF_MEM | BPF_H: 554e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 55562258278SAlexei Starovoitov EMIT3(0x66, 0x41, 0xC7); 55662258278SAlexei Starovoitov else 55762258278SAlexei Starovoitov EMIT2(0x66, 0xC7); 55862258278SAlexei Starovoitov goto st; 55962258278SAlexei Starovoitov case BPF_ST | BPF_MEM | BPF_W: 560e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 56162258278SAlexei Starovoitov EMIT2(0x41, 0xC7); 56262258278SAlexei Starovoitov else 56362258278SAlexei Starovoitov EMIT1(0xC7); 56462258278SAlexei Starovoitov goto st; 56562258278SAlexei Starovoitov case BPF_ST | BPF_MEM | BPF_DW: 566e430f34eSAlexei Starovoitov EMIT2(add_1mod(0x48, dst_reg), 0xC7); 56762258278SAlexei Starovoitov 56862258278SAlexei Starovoitov st: if (is_imm8(insn->off)) 569e430f34eSAlexei Starovoitov EMIT2(add_1reg(0x40, dst_reg), insn->off); 57062258278SAlexei Starovoitov else 571e430f34eSAlexei Starovoitov EMIT1_off32(add_1reg(0x80, dst_reg), insn->off); 57262258278SAlexei Starovoitov 573e430f34eSAlexei Starovoitov EMIT(imm32, bpf_size_to_x86_bytes(BPF_SIZE(insn->code))); 57462258278SAlexei Starovoitov break; 57562258278SAlexei Starovoitov 576e430f34eSAlexei Starovoitov /* STX: *(u8*)(dst_reg + off) = src_reg */ 57762258278SAlexei Starovoitov case BPF_STX | BPF_MEM | BPF_B: 57862258278SAlexei Starovoitov /* emit 'mov byte ptr [rax + off], al' */ 579e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg) || 58062258278SAlexei Starovoitov /* have to add extra byte for x86 SIL, DIL regs */ 581e430f34eSAlexei Starovoitov src_reg == BPF_REG_1 || src_reg == BPF_REG_2) 582e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x40, dst_reg, src_reg), 0x88); 58362258278SAlexei Starovoitov else 58462258278SAlexei Starovoitov EMIT1(0x88); 58562258278SAlexei Starovoitov goto stx; 58662258278SAlexei Starovoitov case BPF_STX | BPF_MEM | BPF_H: 587e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 588e430f34eSAlexei Starovoitov EMIT3(0x66, add_2mod(0x40, dst_reg, src_reg), 0x89); 58962258278SAlexei Starovoitov else 59062258278SAlexei Starovoitov EMIT2(0x66, 0x89); 59162258278SAlexei Starovoitov goto stx; 59262258278SAlexei Starovoitov case BPF_STX | BPF_MEM | BPF_W: 593e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 594e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x40, dst_reg, src_reg), 0x89); 59562258278SAlexei Starovoitov else 59662258278SAlexei Starovoitov EMIT1(0x89); 59762258278SAlexei Starovoitov goto stx; 59862258278SAlexei Starovoitov case BPF_STX | BPF_MEM | BPF_DW: 599e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x48, dst_reg, src_reg), 0x89); 60062258278SAlexei Starovoitov stx: if (is_imm8(insn->off)) 601e430f34eSAlexei Starovoitov EMIT2(add_2reg(0x40, dst_reg, src_reg), insn->off); 60262258278SAlexei Starovoitov else 603e430f34eSAlexei Starovoitov EMIT1_off32(add_2reg(0x80, dst_reg, src_reg), 60462258278SAlexei Starovoitov insn->off); 60562258278SAlexei Starovoitov break; 60662258278SAlexei Starovoitov 607e430f34eSAlexei Starovoitov /* LDX: dst_reg = *(u8*)(src_reg + off) */ 60862258278SAlexei Starovoitov case BPF_LDX | BPF_MEM | BPF_B: 60962258278SAlexei Starovoitov /* emit 'movzx rax, byte ptr [rax + off]' */ 610e430f34eSAlexei Starovoitov EMIT3(add_2mod(0x48, src_reg, dst_reg), 0x0F, 0xB6); 61162258278SAlexei Starovoitov goto ldx; 61262258278SAlexei Starovoitov case BPF_LDX | BPF_MEM | BPF_H: 61362258278SAlexei Starovoitov /* emit 'movzx rax, word ptr [rax + off]' */ 614e430f34eSAlexei Starovoitov EMIT3(add_2mod(0x48, src_reg, dst_reg), 0x0F, 0xB7); 61562258278SAlexei Starovoitov goto ldx; 61662258278SAlexei Starovoitov case BPF_LDX | BPF_MEM | BPF_W: 61762258278SAlexei Starovoitov /* emit 'mov eax, dword ptr [rax+0x14]' */ 618e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 619e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x40, src_reg, dst_reg), 0x8B); 62062258278SAlexei Starovoitov else 62162258278SAlexei Starovoitov EMIT1(0x8B); 62262258278SAlexei Starovoitov goto ldx; 62362258278SAlexei Starovoitov case BPF_LDX | BPF_MEM | BPF_DW: 62462258278SAlexei Starovoitov /* emit 'mov rax, qword ptr [rax+0x14]' */ 625e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x48, src_reg, dst_reg), 0x8B); 62662258278SAlexei Starovoitov ldx: /* if insn->off == 0 we can save one extra byte, but 62762258278SAlexei Starovoitov * special case of x86 r13 which always needs an offset 62862258278SAlexei Starovoitov * is not worth the hassle 62962258278SAlexei Starovoitov */ 63062258278SAlexei Starovoitov if (is_imm8(insn->off)) 631e430f34eSAlexei Starovoitov EMIT2(add_2reg(0x40, src_reg, dst_reg), insn->off); 63262258278SAlexei Starovoitov else 633e430f34eSAlexei Starovoitov EMIT1_off32(add_2reg(0x80, src_reg, dst_reg), 63462258278SAlexei Starovoitov insn->off); 63562258278SAlexei Starovoitov break; 63662258278SAlexei Starovoitov 637e430f34eSAlexei Starovoitov /* STX XADD: lock *(u32*)(dst_reg + off) += src_reg */ 63862258278SAlexei Starovoitov case BPF_STX | BPF_XADD | BPF_W: 63962258278SAlexei Starovoitov /* emit 'lock add dword ptr [rax + off], eax' */ 640e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 641e430f34eSAlexei Starovoitov EMIT3(0xF0, add_2mod(0x40, dst_reg, src_reg), 0x01); 64262258278SAlexei Starovoitov else 64362258278SAlexei Starovoitov EMIT2(0xF0, 0x01); 64462258278SAlexei Starovoitov goto xadd; 64562258278SAlexei Starovoitov case BPF_STX | BPF_XADD | BPF_DW: 646e430f34eSAlexei Starovoitov EMIT3(0xF0, add_2mod(0x48, dst_reg, src_reg), 0x01); 64762258278SAlexei Starovoitov xadd: if (is_imm8(insn->off)) 648e430f34eSAlexei Starovoitov EMIT2(add_2reg(0x40, dst_reg, src_reg), insn->off); 64962258278SAlexei Starovoitov else 650e430f34eSAlexei Starovoitov EMIT1_off32(add_2reg(0x80, dst_reg, src_reg), 65162258278SAlexei Starovoitov insn->off); 65262258278SAlexei Starovoitov break; 65362258278SAlexei Starovoitov 65462258278SAlexei Starovoitov /* call */ 65562258278SAlexei Starovoitov case BPF_JMP | BPF_CALL: 656e430f34eSAlexei Starovoitov func = (u8 *) __bpf_call_base + imm32; 65762258278SAlexei Starovoitov jmp_offset = func - (image + addrs[i]); 65862258278SAlexei Starovoitov if (ctx->seen_ld_abs) { 65962258278SAlexei Starovoitov EMIT2(0x41, 0x52); /* push %r10 */ 66062258278SAlexei Starovoitov EMIT2(0x41, 0x51); /* push %r9 */ 66162258278SAlexei Starovoitov /* need to adjust jmp offset, since 66262258278SAlexei Starovoitov * pop %r9, pop %r10 take 4 bytes after call insn 66362258278SAlexei Starovoitov */ 66462258278SAlexei Starovoitov jmp_offset += 4; 66562258278SAlexei Starovoitov } 666e430f34eSAlexei Starovoitov if (!imm32 || !is_simm32(jmp_offset)) { 66762258278SAlexei Starovoitov pr_err("unsupported bpf func %d addr %p image %p\n", 668e430f34eSAlexei Starovoitov imm32, func, image); 669f3c2af7bSAlexei Starovoitov return -EINVAL; 67062258278SAlexei Starovoitov } 67162258278SAlexei Starovoitov EMIT1_off32(0xE8, jmp_offset); 67262258278SAlexei Starovoitov if (ctx->seen_ld_abs) { 67362258278SAlexei Starovoitov EMIT2(0x41, 0x59); /* pop %r9 */ 67462258278SAlexei Starovoitov EMIT2(0x41, 0x5A); /* pop %r10 */ 67562258278SAlexei Starovoitov } 67662258278SAlexei Starovoitov break; 67762258278SAlexei Starovoitov 67862258278SAlexei Starovoitov /* cond jump */ 67962258278SAlexei Starovoitov case BPF_JMP | BPF_JEQ | BPF_X: 68062258278SAlexei Starovoitov case BPF_JMP | BPF_JNE | BPF_X: 68162258278SAlexei Starovoitov case BPF_JMP | BPF_JGT | BPF_X: 68262258278SAlexei Starovoitov case BPF_JMP | BPF_JGE | BPF_X: 68362258278SAlexei Starovoitov case BPF_JMP | BPF_JSGT | BPF_X: 68462258278SAlexei Starovoitov case BPF_JMP | BPF_JSGE | BPF_X: 685e430f34eSAlexei Starovoitov /* cmp dst_reg, src_reg */ 686e430f34eSAlexei Starovoitov EMIT3(add_2mod(0x48, dst_reg, src_reg), 0x39, 687e430f34eSAlexei Starovoitov add_2reg(0xC0, dst_reg, src_reg)); 68862258278SAlexei Starovoitov goto emit_cond_jmp; 68962258278SAlexei Starovoitov 69062258278SAlexei Starovoitov case BPF_JMP | BPF_JSET | BPF_X: 691e430f34eSAlexei Starovoitov /* test dst_reg, src_reg */ 692e430f34eSAlexei Starovoitov EMIT3(add_2mod(0x48, dst_reg, src_reg), 0x85, 693e430f34eSAlexei Starovoitov add_2reg(0xC0, dst_reg, src_reg)); 69462258278SAlexei Starovoitov goto emit_cond_jmp; 69562258278SAlexei Starovoitov 69662258278SAlexei Starovoitov case BPF_JMP | BPF_JSET | BPF_K: 697e430f34eSAlexei Starovoitov /* test dst_reg, imm32 */ 698e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 699e430f34eSAlexei Starovoitov EMIT2_off32(0xF7, add_1reg(0xC0, dst_reg), imm32); 70062258278SAlexei Starovoitov goto emit_cond_jmp; 70162258278SAlexei Starovoitov 70262258278SAlexei Starovoitov case BPF_JMP | BPF_JEQ | BPF_K: 70362258278SAlexei Starovoitov case BPF_JMP | BPF_JNE | BPF_K: 70462258278SAlexei Starovoitov case BPF_JMP | BPF_JGT | BPF_K: 70562258278SAlexei Starovoitov case BPF_JMP | BPF_JGE | BPF_K: 70662258278SAlexei Starovoitov case BPF_JMP | BPF_JSGT | BPF_K: 70762258278SAlexei Starovoitov case BPF_JMP | BPF_JSGE | BPF_K: 708e430f34eSAlexei Starovoitov /* cmp dst_reg, imm8/32 */ 709e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 71062258278SAlexei Starovoitov 711e430f34eSAlexei Starovoitov if (is_imm8(imm32)) 712e430f34eSAlexei Starovoitov EMIT3(0x83, add_1reg(0xF8, dst_reg), imm32); 71362258278SAlexei Starovoitov else 714e430f34eSAlexei Starovoitov EMIT2_off32(0x81, add_1reg(0xF8, dst_reg), imm32); 71562258278SAlexei Starovoitov 71662258278SAlexei Starovoitov emit_cond_jmp: /* convert BPF opcode to x86 */ 71762258278SAlexei Starovoitov switch (BPF_OP(insn->code)) { 71862258278SAlexei Starovoitov case BPF_JEQ: 71962258278SAlexei Starovoitov jmp_cond = X86_JE; 72062258278SAlexei Starovoitov break; 72162258278SAlexei Starovoitov case BPF_JSET: 72262258278SAlexei Starovoitov case BPF_JNE: 72362258278SAlexei Starovoitov jmp_cond = X86_JNE; 72462258278SAlexei Starovoitov break; 72562258278SAlexei Starovoitov case BPF_JGT: 72662258278SAlexei Starovoitov /* GT is unsigned '>', JA in x86 */ 72762258278SAlexei Starovoitov jmp_cond = X86_JA; 72862258278SAlexei Starovoitov break; 72962258278SAlexei Starovoitov case BPF_JGE: 73062258278SAlexei Starovoitov /* GE is unsigned '>=', JAE in x86 */ 73162258278SAlexei Starovoitov jmp_cond = X86_JAE; 73262258278SAlexei Starovoitov break; 73362258278SAlexei Starovoitov case BPF_JSGT: 73462258278SAlexei Starovoitov /* signed '>', GT in x86 */ 73562258278SAlexei Starovoitov jmp_cond = X86_JG; 73662258278SAlexei Starovoitov break; 73762258278SAlexei Starovoitov case BPF_JSGE: 73862258278SAlexei Starovoitov /* signed '>=', GE in x86 */ 73962258278SAlexei Starovoitov jmp_cond = X86_JGE; 74062258278SAlexei Starovoitov break; 74162258278SAlexei Starovoitov default: /* to silence gcc warning */ 74262258278SAlexei Starovoitov return -EFAULT; 74362258278SAlexei Starovoitov } 74462258278SAlexei Starovoitov jmp_offset = addrs[i + insn->off] - addrs[i]; 74562258278SAlexei Starovoitov if (is_imm8(jmp_offset)) { 74662258278SAlexei Starovoitov EMIT2(jmp_cond, jmp_offset); 74762258278SAlexei Starovoitov } else if (is_simm32(jmp_offset)) { 74862258278SAlexei Starovoitov EMIT2_off32(0x0F, jmp_cond + 0x10, jmp_offset); 7493b58908aSEric Dumazet } else { 75062258278SAlexei Starovoitov pr_err("cond_jmp gen bug %llx\n", jmp_offset); 75162258278SAlexei Starovoitov return -EFAULT; 7523b58908aSEric Dumazet } 75362258278SAlexei Starovoitov 7543b58908aSEric Dumazet break; 75562258278SAlexei Starovoitov 75662258278SAlexei Starovoitov case BPF_JMP | BPF_JA: 75762258278SAlexei Starovoitov jmp_offset = addrs[i + insn->off] - addrs[i]; 75862258278SAlexei Starovoitov if (!jmp_offset) 75962258278SAlexei Starovoitov /* optimize out nop jumps */ 76062258278SAlexei Starovoitov break; 76162258278SAlexei Starovoitov emit_jmp: 76262258278SAlexei Starovoitov if (is_imm8(jmp_offset)) { 76362258278SAlexei Starovoitov EMIT2(0xEB, jmp_offset); 76462258278SAlexei Starovoitov } else if (is_simm32(jmp_offset)) { 76562258278SAlexei Starovoitov EMIT1_off32(0xE9, jmp_offset); 76662258278SAlexei Starovoitov } else { 76762258278SAlexei Starovoitov pr_err("jmp gen bug %llx\n", jmp_offset); 76862258278SAlexei Starovoitov return -EFAULT; 7693b58908aSEric Dumazet } 77062258278SAlexei Starovoitov break; 77162258278SAlexei Starovoitov 77262258278SAlexei Starovoitov case BPF_LD | BPF_IND | BPF_W: 77362258278SAlexei Starovoitov func = sk_load_word; 77462258278SAlexei Starovoitov goto common_load; 77562258278SAlexei Starovoitov case BPF_LD | BPF_ABS | BPF_W: 776e430f34eSAlexei Starovoitov func = CHOOSE_LOAD_FUNC(imm32, sk_load_word); 77762258278SAlexei Starovoitov common_load: ctx->seen_ld_abs = true; 77862258278SAlexei Starovoitov jmp_offset = func - (image + addrs[i]); 77962258278SAlexei Starovoitov if (!func || !is_simm32(jmp_offset)) { 78062258278SAlexei Starovoitov pr_err("unsupported bpf func %d addr %p image %p\n", 781e430f34eSAlexei Starovoitov imm32, func, image); 78262258278SAlexei Starovoitov return -EINVAL; 78362258278SAlexei Starovoitov } 78462258278SAlexei Starovoitov if (BPF_MODE(insn->code) == BPF_ABS) { 78562258278SAlexei Starovoitov /* mov %esi, imm32 */ 786e430f34eSAlexei Starovoitov EMIT1_off32(0xBE, imm32); 78762258278SAlexei Starovoitov } else { 788e430f34eSAlexei Starovoitov /* mov %rsi, src_reg */ 789e430f34eSAlexei Starovoitov EMIT_mov(BPF_REG_2, src_reg); 790e430f34eSAlexei Starovoitov if (imm32) { 791e430f34eSAlexei Starovoitov if (is_imm8(imm32)) 79262258278SAlexei Starovoitov /* add %esi, imm8 */ 793e430f34eSAlexei Starovoitov EMIT3(0x83, 0xC6, imm32); 79462258278SAlexei Starovoitov else 79562258278SAlexei Starovoitov /* add %esi, imm32 */ 796e430f34eSAlexei Starovoitov EMIT2_off32(0x81, 0xC6, imm32); 79762258278SAlexei Starovoitov } 79862258278SAlexei Starovoitov } 79962258278SAlexei Starovoitov /* skb pointer is in R6 (%rbx), it will be copied into 80062258278SAlexei Starovoitov * %rdi if skb_copy_bits() call is necessary. 80162258278SAlexei Starovoitov * sk_load_* helpers also use %r10 and %r9d. 80262258278SAlexei Starovoitov * See bpf_jit.S 80362258278SAlexei Starovoitov */ 80462258278SAlexei Starovoitov EMIT1_off32(0xE8, jmp_offset); /* call */ 8050a14842fSEric Dumazet break; 80662258278SAlexei Starovoitov 80762258278SAlexei Starovoitov case BPF_LD | BPF_IND | BPF_H: 80862258278SAlexei Starovoitov func = sk_load_half; 80962258278SAlexei Starovoitov goto common_load; 81062258278SAlexei Starovoitov case BPF_LD | BPF_ABS | BPF_H: 811e430f34eSAlexei Starovoitov func = CHOOSE_LOAD_FUNC(imm32, sk_load_half); 8120a14842fSEric Dumazet goto common_load; 81362258278SAlexei Starovoitov case BPF_LD | BPF_IND | BPF_B: 81462258278SAlexei Starovoitov func = sk_load_byte; 81562258278SAlexei Starovoitov goto common_load; 81662258278SAlexei Starovoitov case BPF_LD | BPF_ABS | BPF_B: 817e430f34eSAlexei Starovoitov func = CHOOSE_LOAD_FUNC(imm32, sk_load_byte); 8180a14842fSEric Dumazet goto common_load; 8190a14842fSEric Dumazet 82062258278SAlexei Starovoitov case BPF_JMP | BPF_EXIT: 82162258278SAlexei Starovoitov if (i != insn_cnt - 1) { 82262258278SAlexei Starovoitov jmp_offset = ctx->cleanup_addr - addrs[i]; 82362258278SAlexei Starovoitov goto emit_jmp; 82462258278SAlexei Starovoitov } 82562258278SAlexei Starovoitov /* update cleanup_addr */ 82662258278SAlexei Starovoitov ctx->cleanup_addr = proglen; 82762258278SAlexei Starovoitov /* mov rbx, qword ptr [rbp-X] */ 82862258278SAlexei Starovoitov EMIT3_off32(0x48, 0x8B, 0x9D, -stacksize); 82962258278SAlexei Starovoitov /* mov r13, qword ptr [rbp-X] */ 83062258278SAlexei Starovoitov EMIT3_off32(0x4C, 0x8B, 0xAD, -stacksize + 8); 83162258278SAlexei Starovoitov /* mov r14, qword ptr [rbp-X] */ 83262258278SAlexei Starovoitov EMIT3_off32(0x4C, 0x8B, 0xB5, -stacksize + 16); 83362258278SAlexei Starovoitov /* mov r15, qword ptr [rbp-X] */ 83462258278SAlexei Starovoitov EMIT3_off32(0x4C, 0x8B, 0xBD, -stacksize + 24); 8350a14842fSEric Dumazet 83662258278SAlexei Starovoitov EMIT1(0xC9); /* leave */ 83762258278SAlexei Starovoitov EMIT1(0xC3); /* ret */ 8380a14842fSEric Dumazet break; 8390a14842fSEric Dumazet 8400a14842fSEric Dumazet default: 84162258278SAlexei Starovoitov /* By design x64 JIT should support all BPF instructions 84262258278SAlexei Starovoitov * This error will be seen if new instruction was added 84362258278SAlexei Starovoitov * to interpreter, but not to JIT 84462258278SAlexei Starovoitov * or if there is junk in sk_filter 84562258278SAlexei Starovoitov */ 84662258278SAlexei Starovoitov pr_err("bpf_jit: unknown opcode %02x\n", insn->code); 847f3c2af7bSAlexei Starovoitov return -EINVAL; 8480a14842fSEric Dumazet } 84962258278SAlexei Starovoitov 8500a14842fSEric Dumazet ilen = prog - temp; 8510a14842fSEric Dumazet if (image) { 8520a14842fSEric Dumazet if (unlikely(proglen + ilen > oldproglen)) { 85362258278SAlexei Starovoitov pr_err("bpf_jit_compile fatal error\n"); 854f3c2af7bSAlexei Starovoitov return -EFAULT; 8550a14842fSEric Dumazet } 8560a14842fSEric Dumazet memcpy(image + proglen, temp, ilen); 8570a14842fSEric Dumazet } 8580a14842fSEric Dumazet proglen += ilen; 8590a14842fSEric Dumazet addrs[i] = proglen; 8600a14842fSEric Dumazet prog = temp; 8610a14842fSEric Dumazet } 862f3c2af7bSAlexei Starovoitov return proglen; 863f3c2af7bSAlexei Starovoitov } 864f3c2af7bSAlexei Starovoitov 865f3c2af7bSAlexei Starovoitov void bpf_jit_compile(struct sk_filter *prog) 866f3c2af7bSAlexei Starovoitov { 86762258278SAlexei Starovoitov } 86862258278SAlexei Starovoitov 86962258278SAlexei Starovoitov void bpf_int_jit_compile(struct sk_filter *prog) 87062258278SAlexei Starovoitov { 871f3c2af7bSAlexei Starovoitov struct bpf_binary_header *header = NULL; 872f3c2af7bSAlexei Starovoitov int proglen, oldproglen = 0; 873f3c2af7bSAlexei Starovoitov struct jit_context ctx = {}; 874f3c2af7bSAlexei Starovoitov u8 *image = NULL; 875f3c2af7bSAlexei Starovoitov int *addrs; 876f3c2af7bSAlexei Starovoitov int pass; 877f3c2af7bSAlexei Starovoitov int i; 878f3c2af7bSAlexei Starovoitov 879f3c2af7bSAlexei Starovoitov if (!bpf_jit_enable) 880f3c2af7bSAlexei Starovoitov return; 881f3c2af7bSAlexei Starovoitov 882f3c2af7bSAlexei Starovoitov if (!prog || !prog->len) 883f3c2af7bSAlexei Starovoitov return; 884f3c2af7bSAlexei Starovoitov 885f3c2af7bSAlexei Starovoitov addrs = kmalloc(prog->len * sizeof(*addrs), GFP_KERNEL); 886f3c2af7bSAlexei Starovoitov if (!addrs) 887f3c2af7bSAlexei Starovoitov return; 888f3c2af7bSAlexei Starovoitov 889f3c2af7bSAlexei Starovoitov /* Before first pass, make a rough estimation of addrs[] 890f3c2af7bSAlexei Starovoitov * each bpf instruction is translated to less than 64 bytes 891f3c2af7bSAlexei Starovoitov */ 892f3c2af7bSAlexei Starovoitov for (proglen = 0, i = 0; i < prog->len; i++) { 893f3c2af7bSAlexei Starovoitov proglen += 64; 894f3c2af7bSAlexei Starovoitov addrs[i] = proglen; 895f3c2af7bSAlexei Starovoitov } 896f3c2af7bSAlexei Starovoitov ctx.cleanup_addr = proglen; 897f3c2af7bSAlexei Starovoitov 898f3c2af7bSAlexei Starovoitov for (pass = 0; pass < 10; pass++) { 899f3c2af7bSAlexei Starovoitov proglen = do_jit(prog, addrs, image, oldproglen, &ctx); 900f3c2af7bSAlexei Starovoitov if (proglen <= 0) { 901f3c2af7bSAlexei Starovoitov image = NULL; 902f3c2af7bSAlexei Starovoitov if (header) 903f3c2af7bSAlexei Starovoitov module_free(NULL, header); 904f3c2af7bSAlexei Starovoitov goto out; 905f3c2af7bSAlexei Starovoitov } 9060a14842fSEric Dumazet if (image) { 907d00a9dd2SEric Dumazet if (proglen != oldproglen) 908f3c2af7bSAlexei Starovoitov pr_err("bpf_jit: proglen=%d != oldproglen=%d\n", 909f3c2af7bSAlexei Starovoitov proglen, oldproglen); 9100a14842fSEric Dumazet break; 9110a14842fSEric Dumazet } 9120a14842fSEric Dumazet if (proglen == oldproglen) { 913314beb9bSEric Dumazet header = bpf_alloc_binary(proglen, &image); 914314beb9bSEric Dumazet if (!header) 9150a14842fSEric Dumazet goto out; 9160a14842fSEric Dumazet } 9170a14842fSEric Dumazet oldproglen = proglen; 9180a14842fSEric Dumazet } 91979617801SDaniel Borkmann 9200a14842fSEric Dumazet if (bpf_jit_enable > 1) 921f3c2af7bSAlexei Starovoitov bpf_jit_dump(prog->len, proglen, 0, image); 9220a14842fSEric Dumazet 9230a14842fSEric Dumazet if (image) { 924314beb9bSEric Dumazet bpf_flush_icache(header, image + proglen); 925314beb9bSEric Dumazet set_memory_ro((unsigned long)header, header->pages); 926f3c2af7bSAlexei Starovoitov prog->bpf_func = (void *)image; 927f3c2af7bSAlexei Starovoitov prog->jited = 1; 9280a14842fSEric Dumazet } 9290a14842fSEric Dumazet out: 9300a14842fSEric Dumazet kfree(addrs); 9310a14842fSEric Dumazet } 9320a14842fSEric Dumazet 933d45ed4a4SAlexei Starovoitov static void bpf_jit_free_deferred(struct work_struct *work) 9340a14842fSEric Dumazet { 935d45ed4a4SAlexei Starovoitov struct sk_filter *fp = container_of(work, struct sk_filter, work); 936314beb9bSEric Dumazet unsigned long addr = (unsigned long)fp->bpf_func & PAGE_MASK; 937314beb9bSEric Dumazet struct bpf_binary_header *header = (void *)addr; 938314beb9bSEric Dumazet 939314beb9bSEric Dumazet set_memory_rw(addr, header->pages); 940314beb9bSEric Dumazet module_free(NULL, header); 941d45ed4a4SAlexei Starovoitov kfree(fp); 942d45ed4a4SAlexei Starovoitov } 943d45ed4a4SAlexei Starovoitov 944d45ed4a4SAlexei Starovoitov void bpf_jit_free(struct sk_filter *fp) 945d45ed4a4SAlexei Starovoitov { 946f8bbbfc3SDaniel Borkmann if (fp->jited) { 947d45ed4a4SAlexei Starovoitov INIT_WORK(&fp->work, bpf_jit_free_deferred); 948d45ed4a4SAlexei Starovoitov schedule_work(&fp->work); 94998bbc06aSAndrey Vagin } else { 95098bbc06aSAndrey Vagin kfree(fp); 951314beb9bSEric Dumazet } 9520a14842fSEric Dumazet } 953