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> 16a493a87fSDaniel Borkmann #include <asm/nospec-branch.h> 17b52f00e6SAlexei Starovoitov #include <linux/bpf.h> 180a14842fSEric Dumazet 190a14842fSEric Dumazet /* 200a14842fSEric Dumazet * assembly code in arch/x86/net/bpf_jit.S 210a14842fSEric Dumazet */ 2262258278SAlexei Starovoitov extern u8 sk_load_word[], sk_load_half[], sk_load_byte[]; 23a998d434SJan Seiffert extern u8 sk_load_word_positive_offset[], sk_load_half_positive_offset[]; 2462258278SAlexei Starovoitov extern u8 sk_load_byte_positive_offset[]; 25a998d434SJan Seiffert extern u8 sk_load_word_negative_offset[], sk_load_half_negative_offset[]; 2662258278SAlexei Starovoitov extern u8 sk_load_byte_negative_offset[]; 270a14842fSEric Dumazet 285cccc702SJoe Perches static u8 *emit_code(u8 *ptr, u32 bytes, unsigned int len) 290a14842fSEric Dumazet { 300a14842fSEric Dumazet if (len == 1) 310a14842fSEric Dumazet *ptr = bytes; 320a14842fSEric Dumazet else if (len == 2) 330a14842fSEric Dumazet *(u16 *)ptr = bytes; 340a14842fSEric Dumazet else { 350a14842fSEric Dumazet *(u32 *)ptr = bytes; 360a14842fSEric Dumazet barrier(); 370a14842fSEric Dumazet } 380a14842fSEric Dumazet return ptr + len; 390a14842fSEric Dumazet } 400a14842fSEric Dumazet 41b52f00e6SAlexei Starovoitov #define EMIT(bytes, len) \ 42b52f00e6SAlexei Starovoitov do { prog = emit_code(prog, bytes, len); cnt += 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 575cccc702SJoe Perches static bool is_imm8(int value) 580a14842fSEric Dumazet { 590a14842fSEric Dumazet return value <= 127 && value >= -128; 600a14842fSEric Dumazet } 610a14842fSEric Dumazet 625cccc702SJoe Perches static 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 9652afc51eSDaniel Borkmann #define X86_JL 0x7C 9762258278SAlexei Starovoitov #define X86_JGE 0x7D 9852afc51eSDaniel Borkmann #define X86_JLE 0x7E 9962258278SAlexei Starovoitov #define X86_JG 0x7F 1000a14842fSEric Dumazet 1015cccc702SJoe Perches static void bpf_flush_icache(void *start, void *end) 1020a14842fSEric Dumazet { 1030a14842fSEric Dumazet mm_segment_t old_fs = get_fs(); 1040a14842fSEric Dumazet 1050a14842fSEric Dumazet set_fs(KERNEL_DS); 1060a14842fSEric Dumazet smp_wmb(); 1070a14842fSEric Dumazet flush_icache_range((unsigned long)start, (unsigned long)end); 1080a14842fSEric Dumazet set_fs(old_fs); 1090a14842fSEric Dumazet } 1100a14842fSEric Dumazet 111a998d434SJan Seiffert #define CHOOSE_LOAD_FUNC(K, func) \ 112a998d434SJan Seiffert ((int)K < 0 ? ((int)K >= SKF_LL_OFF ? func##_negative_offset : func) : func##_positive_offset) 1130a14842fSEric Dumazet 11462258278SAlexei Starovoitov /* pick a register outside of BPF range for JIT internal work */ 115959a7579SDaniel Borkmann #define AUX_REG (MAX_BPF_JIT_REG + 1) 11662258278SAlexei Starovoitov 117959a7579SDaniel Borkmann /* The following table maps BPF registers to x64 registers. 118959a7579SDaniel Borkmann * 119959a7579SDaniel Borkmann * x64 register r12 is unused, since if used as base address 120959a7579SDaniel Borkmann * register in load/store instructions, it always needs an 121959a7579SDaniel Borkmann * extra byte of encoding and is callee saved. 122959a7579SDaniel Borkmann * 123959a7579SDaniel Borkmann * r9 caches skb->len - skb->data_len 124959a7579SDaniel Borkmann * r10 caches skb->data, and used for blinding (if enabled) 12562258278SAlexei Starovoitov */ 12662258278SAlexei Starovoitov static const int reg2hex[] = { 12762258278SAlexei Starovoitov [BPF_REG_0] = 0, /* rax */ 12862258278SAlexei Starovoitov [BPF_REG_1] = 7, /* rdi */ 12962258278SAlexei Starovoitov [BPF_REG_2] = 6, /* rsi */ 13062258278SAlexei Starovoitov [BPF_REG_3] = 2, /* rdx */ 13162258278SAlexei Starovoitov [BPF_REG_4] = 1, /* rcx */ 13262258278SAlexei Starovoitov [BPF_REG_5] = 0, /* r8 */ 13362258278SAlexei Starovoitov [BPF_REG_6] = 3, /* rbx callee saved */ 13462258278SAlexei Starovoitov [BPF_REG_7] = 5, /* r13 callee saved */ 13562258278SAlexei Starovoitov [BPF_REG_8] = 6, /* r14 callee saved */ 13662258278SAlexei Starovoitov [BPF_REG_9] = 7, /* r15 callee saved */ 13762258278SAlexei Starovoitov [BPF_REG_FP] = 5, /* rbp readonly */ 138959a7579SDaniel Borkmann [BPF_REG_AX] = 2, /* r10 temp register */ 13962258278SAlexei Starovoitov [AUX_REG] = 3, /* r11 temp register */ 14062258278SAlexei Starovoitov }; 14162258278SAlexei Starovoitov 14262258278SAlexei Starovoitov /* is_ereg() == true if BPF register 'reg' maps to x64 r8..r15 14362258278SAlexei Starovoitov * which need extra byte of encoding. 14462258278SAlexei Starovoitov * rax,rcx,...,rbp have simpler encoding 14562258278SAlexei Starovoitov */ 1465cccc702SJoe Perches static bool is_ereg(u32 reg) 14762258278SAlexei Starovoitov { 148d148134bSJoe Perches return (1 << reg) & (BIT(BPF_REG_5) | 149d148134bSJoe Perches BIT(AUX_REG) | 150d148134bSJoe Perches BIT(BPF_REG_7) | 151d148134bSJoe Perches BIT(BPF_REG_8) | 152959a7579SDaniel Borkmann BIT(BPF_REG_9) | 153959a7579SDaniel Borkmann BIT(BPF_REG_AX)); 15462258278SAlexei Starovoitov } 15562258278SAlexei Starovoitov 156de0a444dSDaniel Borkmann static bool is_axreg(u32 reg) 157de0a444dSDaniel Borkmann { 158de0a444dSDaniel Borkmann return reg == BPF_REG_0; 159de0a444dSDaniel Borkmann } 160de0a444dSDaniel Borkmann 16162258278SAlexei Starovoitov /* add modifiers if 'reg' maps to x64 registers r8..r15 */ 1625cccc702SJoe Perches static u8 add_1mod(u8 byte, u32 reg) 16362258278SAlexei Starovoitov { 16462258278SAlexei Starovoitov if (is_ereg(reg)) 16562258278SAlexei Starovoitov byte |= 1; 16662258278SAlexei Starovoitov return byte; 16762258278SAlexei Starovoitov } 16862258278SAlexei Starovoitov 1695cccc702SJoe Perches static u8 add_2mod(u8 byte, u32 r1, u32 r2) 17062258278SAlexei Starovoitov { 17162258278SAlexei Starovoitov if (is_ereg(r1)) 17262258278SAlexei Starovoitov byte |= 1; 17362258278SAlexei Starovoitov if (is_ereg(r2)) 17462258278SAlexei Starovoitov byte |= 4; 17562258278SAlexei Starovoitov return byte; 17662258278SAlexei Starovoitov } 17762258278SAlexei Starovoitov 178e430f34eSAlexei Starovoitov /* encode 'dst_reg' register into x64 opcode 'byte' */ 1795cccc702SJoe Perches static u8 add_1reg(u8 byte, u32 dst_reg) 18062258278SAlexei Starovoitov { 181e430f34eSAlexei Starovoitov return byte + reg2hex[dst_reg]; 18262258278SAlexei Starovoitov } 18362258278SAlexei Starovoitov 184e430f34eSAlexei Starovoitov /* encode 'dst_reg' and 'src_reg' registers into x64 opcode 'byte' */ 1855cccc702SJoe Perches static u8 add_2reg(u8 byte, u32 dst_reg, u32 src_reg) 18662258278SAlexei Starovoitov { 187e430f34eSAlexei Starovoitov return byte + reg2hex[dst_reg] + (reg2hex[src_reg] << 3); 18862258278SAlexei Starovoitov } 18962258278SAlexei Starovoitov 190738cbe72SDaniel Borkmann static void jit_fill_hole(void *area, unsigned int size) 191738cbe72SDaniel Borkmann { 192738cbe72SDaniel Borkmann /* fill whole space with int3 instructions */ 193738cbe72SDaniel Borkmann memset(area, 0xcc, size); 194738cbe72SDaniel Borkmann } 195738cbe72SDaniel Borkmann 196f3c2af7bSAlexei Starovoitov struct jit_context { 197769e0de6SAlexei Starovoitov int cleanup_addr; /* epilogue code offset */ 19862258278SAlexei Starovoitov bool seen_ld_abs; 199959a7579SDaniel Borkmann bool seen_ax_reg; 200f3c2af7bSAlexei Starovoitov }; 201f3c2af7bSAlexei Starovoitov 202e0ee9c12SAlexei Starovoitov /* maximum number of bytes emitted while JITing one eBPF insn */ 203e0ee9c12SAlexei Starovoitov #define BPF_MAX_INSN_SIZE 128 204e0ee9c12SAlexei Starovoitov #define BPF_INSN_SAFETY 64 205e0ee9c12SAlexei Starovoitov 206177366bfSAlexei Starovoitov #define AUX_STACK_SPACE \ 207177366bfSAlexei Starovoitov (32 /* space for rbx, r13, r14, r15 */ + \ 208b52f00e6SAlexei Starovoitov 8 /* space for skb_copy_bits() buffer */) 209b52f00e6SAlexei Starovoitov 210177366bfSAlexei Starovoitov #define PROLOGUE_SIZE 37 211b52f00e6SAlexei Starovoitov 212b52f00e6SAlexei Starovoitov /* emit x64 prologue code for BPF program and check it's size. 213b52f00e6SAlexei Starovoitov * bpf_tail_call helper will skip it while jumping into another program 214b52f00e6SAlexei Starovoitov */ 2152960ae48SAlexei Starovoitov static void emit_prologue(u8 **pprog, u32 stack_depth) 2160a14842fSEric Dumazet { 217b52f00e6SAlexei Starovoitov u8 *prog = *pprog; 218b52f00e6SAlexei Starovoitov int cnt = 0; 2190a14842fSEric Dumazet 22062258278SAlexei Starovoitov EMIT1(0x55); /* push rbp */ 22162258278SAlexei Starovoitov EMIT3(0x48, 0x89, 0xE5); /* mov rbp,rsp */ 2220a14842fSEric Dumazet 2232960ae48SAlexei Starovoitov /* sub rsp, rounded_stack_depth + AUX_STACK_SPACE */ 2242960ae48SAlexei Starovoitov EMIT3_off32(0x48, 0x81, 0xEC, 2252960ae48SAlexei Starovoitov round_up(stack_depth, 8) + AUX_STACK_SPACE); 226177366bfSAlexei Starovoitov 227177366bfSAlexei Starovoitov /* sub rbp, AUX_STACK_SPACE */ 228177366bfSAlexei Starovoitov EMIT4(0x48, 0x83, 0xED, AUX_STACK_SPACE); 2290a14842fSEric Dumazet 23062258278SAlexei Starovoitov /* all classic BPF filters use R6(rbx) save it */ 23162258278SAlexei Starovoitov 232177366bfSAlexei Starovoitov /* mov qword ptr [rbp+0],rbx */ 233177366bfSAlexei Starovoitov EMIT4(0x48, 0x89, 0x5D, 0); 23462258278SAlexei Starovoitov 2358fb575caSAlexei Starovoitov /* bpf_convert_filter() maps classic BPF register X to R7 and uses R8 23662258278SAlexei Starovoitov * as temporary, so all tcpdump filters need to spill/fill R7(r13) and 23762258278SAlexei Starovoitov * R8(r14). R9(r15) spill could be made conditional, but there is only 23862258278SAlexei Starovoitov * one 'bpf_error' return path out of helper functions inside bpf_jit.S 23962258278SAlexei Starovoitov * The overhead of extra spill is negligible for any filter other 24062258278SAlexei Starovoitov * than synthetic ones. Therefore not worth adding complexity. 2410a14842fSEric Dumazet */ 24262258278SAlexei Starovoitov 243177366bfSAlexei Starovoitov /* mov qword ptr [rbp+8],r13 */ 244177366bfSAlexei Starovoitov EMIT4(0x4C, 0x89, 0x6D, 8); 245177366bfSAlexei Starovoitov /* mov qword ptr [rbp+16],r14 */ 246177366bfSAlexei Starovoitov EMIT4(0x4C, 0x89, 0x75, 16); 247177366bfSAlexei Starovoitov /* mov qword ptr [rbp+24],r15 */ 248177366bfSAlexei Starovoitov EMIT4(0x4C, 0x89, 0x7D, 24); 24962258278SAlexei Starovoitov 2508b614aebSDaniel Borkmann /* Clear the tail call counter (tail_call_cnt): for eBPF tail calls 2518b614aebSDaniel Borkmann * we need to reset the counter to 0. It's done in two instructions, 2528b614aebSDaniel Borkmann * resetting rax register to 0 (xor on eax gets 0 extended), and 2538b614aebSDaniel Borkmann * moving it to the counter location. 2548b614aebSDaniel Borkmann */ 25562258278SAlexei Starovoitov 2568b614aebSDaniel Borkmann /* xor eax, eax */ 2578b614aebSDaniel Borkmann EMIT2(0x31, 0xc0); 258177366bfSAlexei Starovoitov /* mov qword ptr [rbp+32], rax */ 259177366bfSAlexei Starovoitov EMIT4(0x48, 0x89, 0x45, 32); 260b52f00e6SAlexei Starovoitov 261b52f00e6SAlexei Starovoitov BUILD_BUG_ON(cnt != PROLOGUE_SIZE); 262b52f00e6SAlexei Starovoitov *pprog = prog; 263b52f00e6SAlexei Starovoitov } 264b52f00e6SAlexei Starovoitov 265b52f00e6SAlexei Starovoitov /* generate the following code: 266b52f00e6SAlexei Starovoitov * ... bpf_tail_call(void *ctx, struct bpf_array *array, u64 index) ... 267b52f00e6SAlexei Starovoitov * if (index >= array->map.max_entries) 268b52f00e6SAlexei Starovoitov * goto out; 269b52f00e6SAlexei Starovoitov * if (++tail_call_cnt > MAX_TAIL_CALL_CNT) 270b52f00e6SAlexei Starovoitov * goto out; 2712a36f0b9SWang Nan * prog = array->ptrs[index]; 272b52f00e6SAlexei Starovoitov * if (prog == NULL) 273b52f00e6SAlexei Starovoitov * goto out; 274b52f00e6SAlexei Starovoitov * goto *(prog->bpf_func + prologue_size); 275b52f00e6SAlexei Starovoitov * out: 276b52f00e6SAlexei Starovoitov */ 277b52f00e6SAlexei Starovoitov static void emit_bpf_tail_call(u8 **pprog) 278b52f00e6SAlexei Starovoitov { 279b52f00e6SAlexei Starovoitov u8 *prog = *pprog; 280b52f00e6SAlexei Starovoitov int label1, label2, label3; 281b52f00e6SAlexei Starovoitov int cnt = 0; 282b52f00e6SAlexei Starovoitov 283b52f00e6SAlexei Starovoitov /* rdi - pointer to ctx 284b52f00e6SAlexei Starovoitov * rsi - pointer to bpf_array 285b52f00e6SAlexei Starovoitov * rdx - index in bpf_array 286b52f00e6SAlexei Starovoitov */ 287b52f00e6SAlexei Starovoitov 288b52f00e6SAlexei Starovoitov /* if (index >= array->map.max_entries) 289b52f00e6SAlexei Starovoitov * goto out; 290b52f00e6SAlexei Starovoitov */ 29190caccddSAlexei Starovoitov EMIT2(0x89, 0xD2); /* mov edx, edx */ 29290caccddSAlexei Starovoitov EMIT3(0x39, 0x56, /* cmp dword ptr [rsi + 16], edx */ 293b52f00e6SAlexei Starovoitov offsetof(struct bpf_array, map.max_entries)); 294a493a87fSDaniel Borkmann #define OFFSET1 (41 + RETPOLINE_RAX_BPF_JIT_SIZE) /* number of bytes to jump */ 295b52f00e6SAlexei Starovoitov EMIT2(X86_JBE, OFFSET1); /* jbe out */ 296b52f00e6SAlexei Starovoitov label1 = cnt; 297b52f00e6SAlexei Starovoitov 298b52f00e6SAlexei Starovoitov /* if (tail_call_cnt > MAX_TAIL_CALL_CNT) 299b52f00e6SAlexei Starovoitov * goto out; 300b52f00e6SAlexei Starovoitov */ 301177366bfSAlexei Starovoitov EMIT2_off32(0x8B, 0x85, 36); /* mov eax, dword ptr [rbp + 36] */ 302b52f00e6SAlexei Starovoitov EMIT3(0x83, 0xF8, MAX_TAIL_CALL_CNT); /* cmp eax, MAX_TAIL_CALL_CNT */ 303a493a87fSDaniel Borkmann #define OFFSET2 (30 + RETPOLINE_RAX_BPF_JIT_SIZE) 304b52f00e6SAlexei Starovoitov EMIT2(X86_JA, OFFSET2); /* ja out */ 305b52f00e6SAlexei Starovoitov label2 = cnt; 306b52f00e6SAlexei Starovoitov EMIT3(0x83, 0xC0, 0x01); /* add eax, 1 */ 307177366bfSAlexei Starovoitov EMIT2_off32(0x89, 0x85, 36); /* mov dword ptr [rbp + 36], eax */ 308b52f00e6SAlexei Starovoitov 3092a36f0b9SWang Nan /* prog = array->ptrs[index]; */ 31084ccac6eSEric Dumazet EMIT4_off32(0x48, 0x8B, 0x84, 0xD6, /* mov rax, [rsi + rdx * 8 + offsetof(...)] */ 3112a36f0b9SWang Nan offsetof(struct bpf_array, ptrs)); 312b52f00e6SAlexei Starovoitov 313b52f00e6SAlexei Starovoitov /* if (prog == NULL) 314b52f00e6SAlexei Starovoitov * goto out; 315b52f00e6SAlexei Starovoitov */ 31684ccac6eSEric Dumazet EMIT3(0x48, 0x85, 0xC0); /* test rax,rax */ 317a493a87fSDaniel Borkmann #define OFFSET3 (8 + RETPOLINE_RAX_BPF_JIT_SIZE) 318b52f00e6SAlexei Starovoitov EMIT2(X86_JE, OFFSET3); /* je out */ 319b52f00e6SAlexei Starovoitov label3 = cnt; 320b52f00e6SAlexei Starovoitov 321b52f00e6SAlexei Starovoitov /* goto *(prog->bpf_func + prologue_size); */ 322b52f00e6SAlexei Starovoitov EMIT4(0x48, 0x8B, 0x40, /* mov rax, qword ptr [rax + 32] */ 323b52f00e6SAlexei Starovoitov offsetof(struct bpf_prog, bpf_func)); 324b52f00e6SAlexei Starovoitov EMIT4(0x48, 0x83, 0xC0, PROLOGUE_SIZE); /* add rax, prologue_size */ 325b52f00e6SAlexei Starovoitov 326b52f00e6SAlexei Starovoitov /* now we're ready to jump into next BPF program 327b52f00e6SAlexei Starovoitov * rdi == ctx (1st arg) 328b52f00e6SAlexei Starovoitov * rax == prog->bpf_func + prologue_size 329b52f00e6SAlexei Starovoitov */ 330a493a87fSDaniel Borkmann RETPOLINE_RAX_BPF_JIT(); 331b52f00e6SAlexei Starovoitov 332b52f00e6SAlexei Starovoitov /* out: */ 333b52f00e6SAlexei Starovoitov BUILD_BUG_ON(cnt - label1 != OFFSET1); 334b52f00e6SAlexei Starovoitov BUILD_BUG_ON(cnt - label2 != OFFSET2); 335b52f00e6SAlexei Starovoitov BUILD_BUG_ON(cnt - label3 != OFFSET3); 336b52f00e6SAlexei Starovoitov *pprog = prog; 337b52f00e6SAlexei Starovoitov } 338b52f00e6SAlexei Starovoitov 3394e10df9aSAlexei Starovoitov 3404e10df9aSAlexei Starovoitov static void emit_load_skb_data_hlen(u8 **pprog) 3414e10df9aSAlexei Starovoitov { 3424e10df9aSAlexei Starovoitov u8 *prog = *pprog; 3434e10df9aSAlexei Starovoitov int cnt = 0; 3444e10df9aSAlexei Starovoitov 3454e10df9aSAlexei Starovoitov /* r9d = skb->len - skb->data_len (headlen) 3464e10df9aSAlexei Starovoitov * r10 = skb->data 3474e10df9aSAlexei Starovoitov */ 3484e10df9aSAlexei Starovoitov /* mov %r9d, off32(%rdi) */ 3494e10df9aSAlexei Starovoitov EMIT3_off32(0x44, 0x8b, 0x8f, offsetof(struct sk_buff, len)); 3504e10df9aSAlexei Starovoitov 3514e10df9aSAlexei Starovoitov /* sub %r9d, off32(%rdi) */ 3524e10df9aSAlexei Starovoitov EMIT3_off32(0x44, 0x2b, 0x8f, offsetof(struct sk_buff, data_len)); 3534e10df9aSAlexei Starovoitov 3544e10df9aSAlexei Starovoitov /* mov %r10, off32(%rdi) */ 3554e10df9aSAlexei Starovoitov EMIT3_off32(0x4c, 0x8b, 0x97, offsetof(struct sk_buff, data)); 3564e10df9aSAlexei Starovoitov *pprog = prog; 3574e10df9aSAlexei Starovoitov } 3584e10df9aSAlexei Starovoitov 359b52f00e6SAlexei Starovoitov static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image, 360b52f00e6SAlexei Starovoitov int oldproglen, struct jit_context *ctx) 361b52f00e6SAlexei Starovoitov { 362b52f00e6SAlexei Starovoitov struct bpf_insn *insn = bpf_prog->insnsi; 363b52f00e6SAlexei Starovoitov int insn_cnt = bpf_prog->len; 364b52f00e6SAlexei Starovoitov bool seen_ld_abs = ctx->seen_ld_abs | (oldproglen == 0); 365959a7579SDaniel Borkmann bool seen_ax_reg = ctx->seen_ax_reg | (oldproglen == 0); 366b52f00e6SAlexei Starovoitov bool seen_exit = false; 367b52f00e6SAlexei Starovoitov u8 temp[BPF_MAX_INSN_SIZE + BPF_INSN_SAFETY]; 368b52f00e6SAlexei Starovoitov int i, cnt = 0; 369b52f00e6SAlexei Starovoitov int proglen = 0; 370b52f00e6SAlexei Starovoitov u8 *prog = temp; 371b52f00e6SAlexei Starovoitov 3722960ae48SAlexei Starovoitov emit_prologue(&prog, bpf_prog->aux->stack_depth); 373b52f00e6SAlexei Starovoitov 3744e10df9aSAlexei Starovoitov if (seen_ld_abs) 3754e10df9aSAlexei Starovoitov emit_load_skb_data_hlen(&prog); 37662258278SAlexei Starovoitov 37762258278SAlexei Starovoitov for (i = 0; i < insn_cnt; i++, insn++) { 378e430f34eSAlexei Starovoitov const s32 imm32 = insn->imm; 379e430f34eSAlexei Starovoitov u32 dst_reg = insn->dst_reg; 380e430f34eSAlexei Starovoitov u32 src_reg = insn->src_reg; 38162258278SAlexei Starovoitov u8 b1 = 0, b2 = 0, b3 = 0; 38262258278SAlexei Starovoitov s64 jmp_offset; 38362258278SAlexei Starovoitov u8 jmp_cond; 3844e10df9aSAlexei Starovoitov bool reload_skb_data; 38562258278SAlexei Starovoitov int ilen; 38662258278SAlexei Starovoitov u8 *func; 38762258278SAlexei Starovoitov 388959a7579SDaniel Borkmann if (dst_reg == BPF_REG_AX || src_reg == BPF_REG_AX) 389959a7579SDaniel Borkmann ctx->seen_ax_reg = seen_ax_reg = true; 390959a7579SDaniel Borkmann 39162258278SAlexei Starovoitov switch (insn->code) { 39262258278SAlexei Starovoitov /* ALU */ 39362258278SAlexei Starovoitov case BPF_ALU | BPF_ADD | BPF_X: 39462258278SAlexei Starovoitov case BPF_ALU | BPF_SUB | BPF_X: 39562258278SAlexei Starovoitov case BPF_ALU | BPF_AND | BPF_X: 39662258278SAlexei Starovoitov case BPF_ALU | BPF_OR | BPF_X: 39762258278SAlexei Starovoitov case BPF_ALU | BPF_XOR | BPF_X: 39862258278SAlexei Starovoitov case BPF_ALU64 | BPF_ADD | BPF_X: 39962258278SAlexei Starovoitov case BPF_ALU64 | BPF_SUB | BPF_X: 40062258278SAlexei Starovoitov case BPF_ALU64 | BPF_AND | BPF_X: 40162258278SAlexei Starovoitov case BPF_ALU64 | BPF_OR | BPF_X: 40262258278SAlexei Starovoitov case BPF_ALU64 | BPF_XOR | BPF_X: 40362258278SAlexei Starovoitov switch (BPF_OP(insn->code)) { 40462258278SAlexei Starovoitov case BPF_ADD: b2 = 0x01; break; 40562258278SAlexei Starovoitov case BPF_SUB: b2 = 0x29; break; 40662258278SAlexei Starovoitov case BPF_AND: b2 = 0x21; break; 40762258278SAlexei Starovoitov case BPF_OR: b2 = 0x09; break; 40862258278SAlexei Starovoitov case BPF_XOR: b2 = 0x31; break; 40962258278SAlexei Starovoitov } 41062258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 411e430f34eSAlexei Starovoitov EMIT1(add_2mod(0x48, dst_reg, src_reg)); 412e430f34eSAlexei Starovoitov else if (is_ereg(dst_reg) || is_ereg(src_reg)) 413e430f34eSAlexei Starovoitov EMIT1(add_2mod(0x40, dst_reg, src_reg)); 414e430f34eSAlexei Starovoitov EMIT2(b2, add_2reg(0xC0, dst_reg, src_reg)); 4150a14842fSEric Dumazet break; 41662258278SAlexei Starovoitov 417e430f34eSAlexei Starovoitov /* mov dst, src */ 41862258278SAlexei Starovoitov case BPF_ALU64 | BPF_MOV | BPF_X: 419e430f34eSAlexei Starovoitov EMIT_mov(dst_reg, src_reg); 42062258278SAlexei Starovoitov break; 42162258278SAlexei Starovoitov 422e430f34eSAlexei Starovoitov /* mov32 dst, src */ 42362258278SAlexei Starovoitov case BPF_ALU | BPF_MOV | BPF_X: 424e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 425e430f34eSAlexei Starovoitov EMIT1(add_2mod(0x40, dst_reg, src_reg)); 426e430f34eSAlexei Starovoitov EMIT2(0x89, add_2reg(0xC0, dst_reg, src_reg)); 42762258278SAlexei Starovoitov break; 42862258278SAlexei Starovoitov 429e430f34eSAlexei Starovoitov /* neg dst */ 43062258278SAlexei Starovoitov case BPF_ALU | BPF_NEG: 43162258278SAlexei Starovoitov case BPF_ALU64 | BPF_NEG: 43262258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 433e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 434e430f34eSAlexei Starovoitov else if (is_ereg(dst_reg)) 435e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x40, dst_reg)); 436e430f34eSAlexei Starovoitov EMIT2(0xF7, add_1reg(0xD8, dst_reg)); 43762258278SAlexei Starovoitov break; 43862258278SAlexei Starovoitov 43962258278SAlexei Starovoitov case BPF_ALU | BPF_ADD | BPF_K: 44062258278SAlexei Starovoitov case BPF_ALU | BPF_SUB | BPF_K: 44162258278SAlexei Starovoitov case BPF_ALU | BPF_AND | BPF_K: 44262258278SAlexei Starovoitov case BPF_ALU | BPF_OR | BPF_K: 44362258278SAlexei Starovoitov case BPF_ALU | BPF_XOR | BPF_K: 44462258278SAlexei Starovoitov case BPF_ALU64 | BPF_ADD | BPF_K: 44562258278SAlexei Starovoitov case BPF_ALU64 | BPF_SUB | BPF_K: 44662258278SAlexei Starovoitov case BPF_ALU64 | BPF_AND | BPF_K: 44762258278SAlexei Starovoitov case BPF_ALU64 | BPF_OR | BPF_K: 44862258278SAlexei Starovoitov case BPF_ALU64 | BPF_XOR | BPF_K: 44962258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 450e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 451e430f34eSAlexei Starovoitov else if (is_ereg(dst_reg)) 452e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x40, dst_reg)); 45362258278SAlexei Starovoitov 454de0a444dSDaniel Borkmann /* b3 holds 'normal' opcode, b2 short form only valid 455de0a444dSDaniel Borkmann * in case dst is eax/rax. 456de0a444dSDaniel Borkmann */ 45762258278SAlexei Starovoitov switch (BPF_OP(insn->code)) { 458de0a444dSDaniel Borkmann case BPF_ADD: 459de0a444dSDaniel Borkmann b3 = 0xC0; 460de0a444dSDaniel Borkmann b2 = 0x05; 461de0a444dSDaniel Borkmann break; 462de0a444dSDaniel Borkmann case BPF_SUB: 463de0a444dSDaniel Borkmann b3 = 0xE8; 464de0a444dSDaniel Borkmann b2 = 0x2D; 465de0a444dSDaniel Borkmann break; 466de0a444dSDaniel Borkmann case BPF_AND: 467de0a444dSDaniel Borkmann b3 = 0xE0; 468de0a444dSDaniel Borkmann b2 = 0x25; 469de0a444dSDaniel Borkmann break; 470de0a444dSDaniel Borkmann case BPF_OR: 471de0a444dSDaniel Borkmann b3 = 0xC8; 472de0a444dSDaniel Borkmann b2 = 0x0D; 473de0a444dSDaniel Borkmann break; 474de0a444dSDaniel Borkmann case BPF_XOR: 475de0a444dSDaniel Borkmann b3 = 0xF0; 476de0a444dSDaniel Borkmann b2 = 0x35; 477de0a444dSDaniel Borkmann break; 47862258278SAlexei Starovoitov } 47962258278SAlexei Starovoitov 480e430f34eSAlexei Starovoitov if (is_imm8(imm32)) 481e430f34eSAlexei Starovoitov EMIT3(0x83, add_1reg(b3, dst_reg), imm32); 482de0a444dSDaniel Borkmann else if (is_axreg(dst_reg)) 483de0a444dSDaniel Borkmann EMIT1_off32(b2, imm32); 48462258278SAlexei Starovoitov else 485e430f34eSAlexei Starovoitov EMIT2_off32(0x81, add_1reg(b3, dst_reg), imm32); 48662258278SAlexei Starovoitov break; 48762258278SAlexei Starovoitov 48862258278SAlexei Starovoitov case BPF_ALU64 | BPF_MOV | BPF_K: 48962258278SAlexei Starovoitov /* optimization: if imm32 is positive, 49062258278SAlexei Starovoitov * use 'mov eax, imm32' (which zero-extends imm32) 49162258278SAlexei Starovoitov * to save 2 bytes 492d00a9dd2SEric Dumazet */ 493e430f34eSAlexei Starovoitov if (imm32 < 0) { 49462258278SAlexei Starovoitov /* 'mov rax, imm32' sign extends imm32 */ 495e430f34eSAlexei Starovoitov b1 = add_1mod(0x48, dst_reg); 49662258278SAlexei Starovoitov b2 = 0xC7; 49762258278SAlexei Starovoitov b3 = 0xC0; 498e430f34eSAlexei Starovoitov EMIT3_off32(b1, b2, add_1reg(b3, dst_reg), imm32); 499aee636c4SEric Dumazet break; 500aee636c4SEric Dumazet } 5013b58908aSEric Dumazet 50262258278SAlexei Starovoitov case BPF_ALU | BPF_MOV | BPF_K: 503606c88a8SDaniel Borkmann /* optimization: if imm32 is zero, use 'xor <dst>,<dst>' 504606c88a8SDaniel Borkmann * to save 3 bytes. 505606c88a8SDaniel Borkmann */ 506606c88a8SDaniel Borkmann if (imm32 == 0) { 507606c88a8SDaniel Borkmann if (is_ereg(dst_reg)) 508606c88a8SDaniel Borkmann EMIT1(add_2mod(0x40, dst_reg, dst_reg)); 509606c88a8SDaniel Borkmann b2 = 0x31; /* xor */ 510606c88a8SDaniel Borkmann b3 = 0xC0; 511606c88a8SDaniel Borkmann EMIT2(b2, add_2reg(b3, dst_reg, dst_reg)); 512606c88a8SDaniel Borkmann break; 513606c88a8SDaniel Borkmann } 514606c88a8SDaniel Borkmann 51562258278SAlexei Starovoitov /* mov %eax, imm32 */ 516e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 517e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x40, dst_reg)); 518e430f34eSAlexei Starovoitov EMIT1_off32(add_1reg(0xB8, dst_reg), imm32); 51962258278SAlexei Starovoitov break; 52062258278SAlexei Starovoitov 52102ab695bSAlexei Starovoitov case BPF_LD | BPF_IMM | BPF_DW: 522606c88a8SDaniel Borkmann /* optimization: if imm64 is zero, use 'xor <dst>,<dst>' 523606c88a8SDaniel Borkmann * to save 7 bytes. 524606c88a8SDaniel Borkmann */ 525606c88a8SDaniel Borkmann if (insn[0].imm == 0 && insn[1].imm == 0) { 526606c88a8SDaniel Borkmann b1 = add_2mod(0x48, dst_reg, dst_reg); 527606c88a8SDaniel Borkmann b2 = 0x31; /* xor */ 528606c88a8SDaniel Borkmann b3 = 0xC0; 529606c88a8SDaniel Borkmann EMIT3(b1, b2, add_2reg(b3, dst_reg, dst_reg)); 530606c88a8SDaniel Borkmann 531606c88a8SDaniel Borkmann insn++; 532606c88a8SDaniel Borkmann i++; 533606c88a8SDaniel Borkmann break; 534606c88a8SDaniel Borkmann } 535606c88a8SDaniel Borkmann 53602ab695bSAlexei Starovoitov /* movabsq %rax, imm64 */ 53702ab695bSAlexei Starovoitov EMIT2(add_1mod(0x48, dst_reg), add_1reg(0xB8, dst_reg)); 53802ab695bSAlexei Starovoitov EMIT(insn[0].imm, 4); 53902ab695bSAlexei Starovoitov EMIT(insn[1].imm, 4); 54002ab695bSAlexei Starovoitov 54102ab695bSAlexei Starovoitov insn++; 54202ab695bSAlexei Starovoitov i++; 54302ab695bSAlexei Starovoitov break; 54402ab695bSAlexei Starovoitov 545e430f34eSAlexei Starovoitov /* dst %= src, dst /= src, dst %= imm32, dst /= imm32 */ 54662258278SAlexei Starovoitov case BPF_ALU | BPF_MOD | BPF_X: 54762258278SAlexei Starovoitov case BPF_ALU | BPF_DIV | BPF_X: 54862258278SAlexei Starovoitov case BPF_ALU | BPF_MOD | BPF_K: 54962258278SAlexei Starovoitov case BPF_ALU | BPF_DIV | BPF_K: 55062258278SAlexei Starovoitov case BPF_ALU64 | BPF_MOD | BPF_X: 55162258278SAlexei Starovoitov case BPF_ALU64 | BPF_DIV | BPF_X: 55262258278SAlexei Starovoitov case BPF_ALU64 | BPF_MOD | BPF_K: 55362258278SAlexei Starovoitov case BPF_ALU64 | BPF_DIV | BPF_K: 55462258278SAlexei Starovoitov EMIT1(0x50); /* push rax */ 55562258278SAlexei Starovoitov EMIT1(0x52); /* push rdx */ 55662258278SAlexei Starovoitov 55762258278SAlexei Starovoitov if (BPF_SRC(insn->code) == BPF_X) 558e430f34eSAlexei Starovoitov /* mov r11, src_reg */ 559e430f34eSAlexei Starovoitov EMIT_mov(AUX_REG, src_reg); 56062258278SAlexei Starovoitov else 561e430f34eSAlexei Starovoitov /* mov r11, imm32 */ 562e430f34eSAlexei Starovoitov EMIT3_off32(0x49, 0xC7, 0xC3, imm32); 56362258278SAlexei Starovoitov 564e430f34eSAlexei Starovoitov /* mov rax, dst_reg */ 565e430f34eSAlexei Starovoitov EMIT_mov(BPF_REG_0, dst_reg); 56662258278SAlexei Starovoitov 56762258278SAlexei Starovoitov /* xor edx, edx 56862258278SAlexei Starovoitov * equivalent to 'xor rdx, rdx', but one byte less 56962258278SAlexei Starovoitov */ 57062258278SAlexei Starovoitov EMIT2(0x31, 0xd2); 57162258278SAlexei Starovoitov 57262258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 57362258278SAlexei Starovoitov /* div r11 */ 57462258278SAlexei Starovoitov EMIT3(0x49, 0xF7, 0xF3); 57562258278SAlexei Starovoitov else 57662258278SAlexei Starovoitov /* div r11d */ 57762258278SAlexei Starovoitov EMIT3(0x41, 0xF7, 0xF3); 57862258278SAlexei Starovoitov 57962258278SAlexei Starovoitov if (BPF_OP(insn->code) == BPF_MOD) 58062258278SAlexei Starovoitov /* mov r11, rdx */ 58162258278SAlexei Starovoitov EMIT3(0x49, 0x89, 0xD3); 58262258278SAlexei Starovoitov else 58362258278SAlexei Starovoitov /* mov r11, rax */ 58462258278SAlexei Starovoitov EMIT3(0x49, 0x89, 0xC3); 58562258278SAlexei Starovoitov 58662258278SAlexei Starovoitov EMIT1(0x5A); /* pop rdx */ 58762258278SAlexei Starovoitov EMIT1(0x58); /* pop rax */ 58862258278SAlexei Starovoitov 589e430f34eSAlexei Starovoitov /* mov dst_reg, r11 */ 590e430f34eSAlexei Starovoitov EMIT_mov(dst_reg, AUX_REG); 59162258278SAlexei Starovoitov break; 59262258278SAlexei Starovoitov 59362258278SAlexei Starovoitov case BPF_ALU | BPF_MUL | BPF_K: 59462258278SAlexei Starovoitov case BPF_ALU | BPF_MUL | BPF_X: 59562258278SAlexei Starovoitov case BPF_ALU64 | BPF_MUL | BPF_K: 59662258278SAlexei Starovoitov case BPF_ALU64 | BPF_MUL | BPF_X: 59762258278SAlexei Starovoitov EMIT1(0x50); /* push rax */ 59862258278SAlexei Starovoitov EMIT1(0x52); /* push rdx */ 59962258278SAlexei Starovoitov 600e430f34eSAlexei Starovoitov /* mov r11, dst_reg */ 601e430f34eSAlexei Starovoitov EMIT_mov(AUX_REG, dst_reg); 60262258278SAlexei Starovoitov 60362258278SAlexei Starovoitov if (BPF_SRC(insn->code) == BPF_X) 604e430f34eSAlexei Starovoitov /* mov rax, src_reg */ 605e430f34eSAlexei Starovoitov EMIT_mov(BPF_REG_0, src_reg); 60662258278SAlexei Starovoitov else 607e430f34eSAlexei Starovoitov /* mov rax, imm32 */ 608e430f34eSAlexei Starovoitov EMIT3_off32(0x48, 0xC7, 0xC0, imm32); 60962258278SAlexei Starovoitov 61062258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 61162258278SAlexei Starovoitov EMIT1(add_1mod(0x48, AUX_REG)); 61262258278SAlexei Starovoitov else if (is_ereg(AUX_REG)) 61362258278SAlexei Starovoitov EMIT1(add_1mod(0x40, AUX_REG)); 61462258278SAlexei Starovoitov /* mul(q) r11 */ 61562258278SAlexei Starovoitov EMIT2(0xF7, add_1reg(0xE0, AUX_REG)); 61662258278SAlexei Starovoitov 61762258278SAlexei Starovoitov /* mov r11, rax */ 61862258278SAlexei Starovoitov EMIT_mov(AUX_REG, BPF_REG_0); 61962258278SAlexei Starovoitov 62062258278SAlexei Starovoitov EMIT1(0x5A); /* pop rdx */ 62162258278SAlexei Starovoitov EMIT1(0x58); /* pop rax */ 62262258278SAlexei Starovoitov 623e430f34eSAlexei Starovoitov /* mov dst_reg, r11 */ 624e430f34eSAlexei Starovoitov EMIT_mov(dst_reg, AUX_REG); 62562258278SAlexei Starovoitov break; 62662258278SAlexei Starovoitov 62762258278SAlexei Starovoitov /* shifts */ 62862258278SAlexei Starovoitov case BPF_ALU | BPF_LSH | BPF_K: 62962258278SAlexei Starovoitov case BPF_ALU | BPF_RSH | BPF_K: 63062258278SAlexei Starovoitov case BPF_ALU | BPF_ARSH | BPF_K: 63162258278SAlexei Starovoitov case BPF_ALU64 | BPF_LSH | BPF_K: 63262258278SAlexei Starovoitov case BPF_ALU64 | BPF_RSH | BPF_K: 63362258278SAlexei Starovoitov case BPF_ALU64 | BPF_ARSH | BPF_K: 63462258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 635e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 636e430f34eSAlexei Starovoitov else if (is_ereg(dst_reg)) 637e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x40, dst_reg)); 63862258278SAlexei Starovoitov 63962258278SAlexei Starovoitov switch (BPF_OP(insn->code)) { 64062258278SAlexei Starovoitov case BPF_LSH: b3 = 0xE0; break; 64162258278SAlexei Starovoitov case BPF_RSH: b3 = 0xE8; break; 64262258278SAlexei Starovoitov case BPF_ARSH: b3 = 0xF8; break; 64362258278SAlexei Starovoitov } 644e430f34eSAlexei Starovoitov EMIT3(0xC1, add_1reg(b3, dst_reg), imm32); 64562258278SAlexei Starovoitov break; 64662258278SAlexei Starovoitov 64772b603eeSAlexei Starovoitov case BPF_ALU | BPF_LSH | BPF_X: 64872b603eeSAlexei Starovoitov case BPF_ALU | BPF_RSH | BPF_X: 64972b603eeSAlexei Starovoitov case BPF_ALU | BPF_ARSH | BPF_X: 65072b603eeSAlexei Starovoitov case BPF_ALU64 | BPF_LSH | BPF_X: 65172b603eeSAlexei Starovoitov case BPF_ALU64 | BPF_RSH | BPF_X: 65272b603eeSAlexei Starovoitov case BPF_ALU64 | BPF_ARSH | BPF_X: 65372b603eeSAlexei Starovoitov 65472b603eeSAlexei Starovoitov /* check for bad case when dst_reg == rcx */ 65572b603eeSAlexei Starovoitov if (dst_reg == BPF_REG_4) { 65672b603eeSAlexei Starovoitov /* mov r11, dst_reg */ 65772b603eeSAlexei Starovoitov EMIT_mov(AUX_REG, dst_reg); 65872b603eeSAlexei Starovoitov dst_reg = AUX_REG; 65972b603eeSAlexei Starovoitov } 66072b603eeSAlexei Starovoitov 66172b603eeSAlexei Starovoitov if (src_reg != BPF_REG_4) { /* common case */ 66272b603eeSAlexei Starovoitov EMIT1(0x51); /* push rcx */ 66372b603eeSAlexei Starovoitov 66472b603eeSAlexei Starovoitov /* mov rcx, src_reg */ 66572b603eeSAlexei Starovoitov EMIT_mov(BPF_REG_4, src_reg); 66672b603eeSAlexei Starovoitov } 66772b603eeSAlexei Starovoitov 66872b603eeSAlexei Starovoitov /* shl %rax, %cl | shr %rax, %cl | sar %rax, %cl */ 66972b603eeSAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 67072b603eeSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 67172b603eeSAlexei Starovoitov else if (is_ereg(dst_reg)) 67272b603eeSAlexei Starovoitov EMIT1(add_1mod(0x40, dst_reg)); 67372b603eeSAlexei Starovoitov 67472b603eeSAlexei Starovoitov switch (BPF_OP(insn->code)) { 67572b603eeSAlexei Starovoitov case BPF_LSH: b3 = 0xE0; break; 67672b603eeSAlexei Starovoitov case BPF_RSH: b3 = 0xE8; break; 67772b603eeSAlexei Starovoitov case BPF_ARSH: b3 = 0xF8; break; 67872b603eeSAlexei Starovoitov } 67972b603eeSAlexei Starovoitov EMIT2(0xD3, add_1reg(b3, dst_reg)); 68072b603eeSAlexei Starovoitov 68172b603eeSAlexei Starovoitov if (src_reg != BPF_REG_4) 68272b603eeSAlexei Starovoitov EMIT1(0x59); /* pop rcx */ 68372b603eeSAlexei Starovoitov 68472b603eeSAlexei Starovoitov if (insn->dst_reg == BPF_REG_4) 68572b603eeSAlexei Starovoitov /* mov dst_reg, r11 */ 68672b603eeSAlexei Starovoitov EMIT_mov(insn->dst_reg, AUX_REG); 68772b603eeSAlexei Starovoitov break; 68872b603eeSAlexei Starovoitov 68962258278SAlexei Starovoitov case BPF_ALU | BPF_END | BPF_FROM_BE: 690e430f34eSAlexei Starovoitov switch (imm32) { 69162258278SAlexei Starovoitov case 16: 69262258278SAlexei Starovoitov /* emit 'ror %ax, 8' to swap lower 2 bytes */ 69362258278SAlexei Starovoitov EMIT1(0x66); 694e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 69562258278SAlexei Starovoitov EMIT1(0x41); 696e430f34eSAlexei Starovoitov EMIT3(0xC1, add_1reg(0xC8, dst_reg), 8); 697343f845bSAlexei Starovoitov 698343f845bSAlexei Starovoitov /* emit 'movzwl eax, ax' */ 699343f845bSAlexei Starovoitov if (is_ereg(dst_reg)) 700343f845bSAlexei Starovoitov EMIT3(0x45, 0x0F, 0xB7); 701343f845bSAlexei Starovoitov else 702343f845bSAlexei Starovoitov EMIT2(0x0F, 0xB7); 703343f845bSAlexei Starovoitov EMIT1(add_2reg(0xC0, dst_reg, dst_reg)); 70462258278SAlexei Starovoitov break; 70562258278SAlexei Starovoitov case 32: 70662258278SAlexei Starovoitov /* emit 'bswap eax' to swap lower 4 bytes */ 707e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 70862258278SAlexei Starovoitov EMIT2(0x41, 0x0F); 70962258278SAlexei Starovoitov else 71062258278SAlexei Starovoitov EMIT1(0x0F); 711e430f34eSAlexei Starovoitov EMIT1(add_1reg(0xC8, dst_reg)); 71262258278SAlexei Starovoitov break; 71362258278SAlexei Starovoitov case 64: 71462258278SAlexei Starovoitov /* emit 'bswap rax' to swap 8 bytes */ 715e430f34eSAlexei Starovoitov EMIT3(add_1mod(0x48, dst_reg), 0x0F, 716e430f34eSAlexei Starovoitov add_1reg(0xC8, dst_reg)); 71762258278SAlexei Starovoitov break; 71862258278SAlexei Starovoitov } 71962258278SAlexei Starovoitov break; 72062258278SAlexei Starovoitov 72162258278SAlexei Starovoitov case BPF_ALU | BPF_END | BPF_FROM_LE: 722343f845bSAlexei Starovoitov switch (imm32) { 723343f845bSAlexei Starovoitov case 16: 724343f845bSAlexei Starovoitov /* emit 'movzwl eax, ax' to zero extend 16-bit 725343f845bSAlexei Starovoitov * into 64 bit 726343f845bSAlexei Starovoitov */ 727343f845bSAlexei Starovoitov if (is_ereg(dst_reg)) 728343f845bSAlexei Starovoitov EMIT3(0x45, 0x0F, 0xB7); 729343f845bSAlexei Starovoitov else 730343f845bSAlexei Starovoitov EMIT2(0x0F, 0xB7); 731343f845bSAlexei Starovoitov EMIT1(add_2reg(0xC0, dst_reg, dst_reg)); 732343f845bSAlexei Starovoitov break; 733343f845bSAlexei Starovoitov case 32: 734343f845bSAlexei Starovoitov /* emit 'mov eax, eax' to clear upper 32-bits */ 735343f845bSAlexei Starovoitov if (is_ereg(dst_reg)) 736343f845bSAlexei Starovoitov EMIT1(0x45); 737343f845bSAlexei Starovoitov EMIT2(0x89, add_2reg(0xC0, dst_reg, dst_reg)); 738343f845bSAlexei Starovoitov break; 739343f845bSAlexei Starovoitov case 64: 740343f845bSAlexei Starovoitov /* nop */ 741343f845bSAlexei Starovoitov break; 742343f845bSAlexei Starovoitov } 74362258278SAlexei Starovoitov break; 74462258278SAlexei Starovoitov 745e430f34eSAlexei Starovoitov /* ST: *(u8*)(dst_reg + off) = imm */ 74662258278SAlexei Starovoitov case BPF_ST | BPF_MEM | BPF_B: 747e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 74862258278SAlexei Starovoitov EMIT2(0x41, 0xC6); 74962258278SAlexei Starovoitov else 75062258278SAlexei Starovoitov EMIT1(0xC6); 75162258278SAlexei Starovoitov goto st; 75262258278SAlexei Starovoitov case BPF_ST | BPF_MEM | BPF_H: 753e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 75462258278SAlexei Starovoitov EMIT3(0x66, 0x41, 0xC7); 75562258278SAlexei Starovoitov else 75662258278SAlexei Starovoitov EMIT2(0x66, 0xC7); 75762258278SAlexei Starovoitov goto st; 75862258278SAlexei Starovoitov case BPF_ST | BPF_MEM | BPF_W: 759e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 76062258278SAlexei Starovoitov EMIT2(0x41, 0xC7); 76162258278SAlexei Starovoitov else 76262258278SAlexei Starovoitov EMIT1(0xC7); 76362258278SAlexei Starovoitov goto st; 76462258278SAlexei Starovoitov case BPF_ST | BPF_MEM | BPF_DW: 765e430f34eSAlexei Starovoitov EMIT2(add_1mod(0x48, dst_reg), 0xC7); 76662258278SAlexei Starovoitov 76762258278SAlexei Starovoitov st: if (is_imm8(insn->off)) 768e430f34eSAlexei Starovoitov EMIT2(add_1reg(0x40, dst_reg), insn->off); 76962258278SAlexei Starovoitov else 770e430f34eSAlexei Starovoitov EMIT1_off32(add_1reg(0x80, dst_reg), insn->off); 77162258278SAlexei Starovoitov 772e430f34eSAlexei Starovoitov EMIT(imm32, bpf_size_to_x86_bytes(BPF_SIZE(insn->code))); 77362258278SAlexei Starovoitov break; 77462258278SAlexei Starovoitov 775e430f34eSAlexei Starovoitov /* STX: *(u8*)(dst_reg + off) = src_reg */ 77662258278SAlexei Starovoitov case BPF_STX | BPF_MEM | BPF_B: 77762258278SAlexei Starovoitov /* emit 'mov byte ptr [rax + off], al' */ 778e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg) || 77962258278SAlexei Starovoitov /* have to add extra byte for x86 SIL, DIL regs */ 780e430f34eSAlexei Starovoitov src_reg == BPF_REG_1 || src_reg == BPF_REG_2) 781e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x40, dst_reg, src_reg), 0x88); 78262258278SAlexei Starovoitov else 78362258278SAlexei Starovoitov EMIT1(0x88); 78462258278SAlexei Starovoitov goto stx; 78562258278SAlexei Starovoitov case BPF_STX | BPF_MEM | BPF_H: 786e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 787e430f34eSAlexei Starovoitov EMIT3(0x66, add_2mod(0x40, dst_reg, src_reg), 0x89); 78862258278SAlexei Starovoitov else 78962258278SAlexei Starovoitov EMIT2(0x66, 0x89); 79062258278SAlexei Starovoitov goto stx; 79162258278SAlexei Starovoitov case BPF_STX | BPF_MEM | BPF_W: 792e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 793e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x40, dst_reg, src_reg), 0x89); 79462258278SAlexei Starovoitov else 79562258278SAlexei Starovoitov EMIT1(0x89); 79662258278SAlexei Starovoitov goto stx; 79762258278SAlexei Starovoitov case BPF_STX | BPF_MEM | BPF_DW: 798e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x48, dst_reg, src_reg), 0x89); 79962258278SAlexei Starovoitov stx: if (is_imm8(insn->off)) 800e430f34eSAlexei Starovoitov EMIT2(add_2reg(0x40, dst_reg, src_reg), insn->off); 80162258278SAlexei Starovoitov else 802e430f34eSAlexei Starovoitov EMIT1_off32(add_2reg(0x80, dst_reg, src_reg), 80362258278SAlexei Starovoitov insn->off); 80462258278SAlexei Starovoitov break; 80562258278SAlexei Starovoitov 806e430f34eSAlexei Starovoitov /* LDX: dst_reg = *(u8*)(src_reg + off) */ 80762258278SAlexei Starovoitov case BPF_LDX | BPF_MEM | BPF_B: 80862258278SAlexei Starovoitov /* emit 'movzx rax, byte ptr [rax + off]' */ 809e430f34eSAlexei Starovoitov EMIT3(add_2mod(0x48, src_reg, dst_reg), 0x0F, 0xB6); 81062258278SAlexei Starovoitov goto ldx; 81162258278SAlexei Starovoitov case BPF_LDX | BPF_MEM | BPF_H: 81262258278SAlexei Starovoitov /* emit 'movzx rax, word ptr [rax + off]' */ 813e430f34eSAlexei Starovoitov EMIT3(add_2mod(0x48, src_reg, dst_reg), 0x0F, 0xB7); 81462258278SAlexei Starovoitov goto ldx; 81562258278SAlexei Starovoitov case BPF_LDX | BPF_MEM | BPF_W: 81662258278SAlexei Starovoitov /* emit 'mov eax, dword ptr [rax+0x14]' */ 817e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 818e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x40, src_reg, dst_reg), 0x8B); 81962258278SAlexei Starovoitov else 82062258278SAlexei Starovoitov EMIT1(0x8B); 82162258278SAlexei Starovoitov goto ldx; 82262258278SAlexei Starovoitov case BPF_LDX | BPF_MEM | BPF_DW: 82362258278SAlexei Starovoitov /* emit 'mov rax, qword ptr [rax+0x14]' */ 824e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x48, src_reg, dst_reg), 0x8B); 82562258278SAlexei Starovoitov ldx: /* if insn->off == 0 we can save one extra byte, but 82662258278SAlexei Starovoitov * special case of x86 r13 which always needs an offset 82762258278SAlexei Starovoitov * is not worth the hassle 82862258278SAlexei Starovoitov */ 82962258278SAlexei Starovoitov if (is_imm8(insn->off)) 830e430f34eSAlexei Starovoitov EMIT2(add_2reg(0x40, src_reg, dst_reg), insn->off); 83162258278SAlexei Starovoitov else 832e430f34eSAlexei Starovoitov EMIT1_off32(add_2reg(0x80, src_reg, dst_reg), 83362258278SAlexei Starovoitov insn->off); 83462258278SAlexei Starovoitov break; 83562258278SAlexei Starovoitov 836e430f34eSAlexei Starovoitov /* STX XADD: lock *(u32*)(dst_reg + off) += src_reg */ 83762258278SAlexei Starovoitov case BPF_STX | BPF_XADD | BPF_W: 83862258278SAlexei Starovoitov /* emit 'lock add dword ptr [rax + off], eax' */ 839e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 840e430f34eSAlexei Starovoitov EMIT3(0xF0, add_2mod(0x40, dst_reg, src_reg), 0x01); 84162258278SAlexei Starovoitov else 84262258278SAlexei Starovoitov EMIT2(0xF0, 0x01); 84362258278SAlexei Starovoitov goto xadd; 84462258278SAlexei Starovoitov case BPF_STX | BPF_XADD | BPF_DW: 845e430f34eSAlexei Starovoitov EMIT3(0xF0, add_2mod(0x48, dst_reg, src_reg), 0x01); 84662258278SAlexei Starovoitov xadd: if (is_imm8(insn->off)) 847e430f34eSAlexei Starovoitov EMIT2(add_2reg(0x40, dst_reg, src_reg), insn->off); 84862258278SAlexei Starovoitov else 849e430f34eSAlexei Starovoitov EMIT1_off32(add_2reg(0x80, dst_reg, src_reg), 85062258278SAlexei Starovoitov insn->off); 85162258278SAlexei Starovoitov break; 85262258278SAlexei Starovoitov 85362258278SAlexei Starovoitov /* call */ 85462258278SAlexei Starovoitov case BPF_JMP | BPF_CALL: 855e430f34eSAlexei Starovoitov func = (u8 *) __bpf_call_base + imm32; 85662258278SAlexei Starovoitov jmp_offset = func - (image + addrs[i]); 857e0ee9c12SAlexei Starovoitov if (seen_ld_abs) { 85817bedab2SMartin KaFai Lau reload_skb_data = bpf_helper_changes_pkt_data(func); 8594e10df9aSAlexei Starovoitov if (reload_skb_data) { 8604e10df9aSAlexei Starovoitov EMIT1(0x57); /* push %rdi */ 8614e10df9aSAlexei Starovoitov jmp_offset += 22; /* pop, mov, sub, mov */ 8624e10df9aSAlexei Starovoitov } else { 86362258278SAlexei Starovoitov EMIT2(0x41, 0x52); /* push %r10 */ 86462258278SAlexei Starovoitov EMIT2(0x41, 0x51); /* push %r9 */ 86562258278SAlexei Starovoitov /* need to adjust jmp offset, since 86662258278SAlexei Starovoitov * pop %r9, pop %r10 take 4 bytes after call insn 86762258278SAlexei Starovoitov */ 86862258278SAlexei Starovoitov jmp_offset += 4; 86962258278SAlexei Starovoitov } 8704e10df9aSAlexei Starovoitov } 871e430f34eSAlexei Starovoitov if (!imm32 || !is_simm32(jmp_offset)) { 87262258278SAlexei Starovoitov pr_err("unsupported bpf func %d addr %p image %p\n", 873e430f34eSAlexei Starovoitov imm32, func, image); 874f3c2af7bSAlexei Starovoitov return -EINVAL; 87562258278SAlexei Starovoitov } 87662258278SAlexei Starovoitov EMIT1_off32(0xE8, jmp_offset); 877e0ee9c12SAlexei Starovoitov if (seen_ld_abs) { 8784e10df9aSAlexei Starovoitov if (reload_skb_data) { 8794e10df9aSAlexei Starovoitov EMIT1(0x5F); /* pop %rdi */ 8804e10df9aSAlexei Starovoitov emit_load_skb_data_hlen(&prog); 8814e10df9aSAlexei Starovoitov } else { 88262258278SAlexei Starovoitov EMIT2(0x41, 0x59); /* pop %r9 */ 88362258278SAlexei Starovoitov EMIT2(0x41, 0x5A); /* pop %r10 */ 88462258278SAlexei Starovoitov } 8854e10df9aSAlexei Starovoitov } 88662258278SAlexei Starovoitov break; 88762258278SAlexei Starovoitov 88871189fa9SAlexei Starovoitov case BPF_JMP | BPF_TAIL_CALL: 889b52f00e6SAlexei Starovoitov emit_bpf_tail_call(&prog); 890b52f00e6SAlexei Starovoitov break; 891b52f00e6SAlexei Starovoitov 89262258278SAlexei Starovoitov /* cond jump */ 89362258278SAlexei Starovoitov case BPF_JMP | BPF_JEQ | BPF_X: 89462258278SAlexei Starovoitov case BPF_JMP | BPF_JNE | BPF_X: 89562258278SAlexei Starovoitov case BPF_JMP | BPF_JGT | BPF_X: 89652afc51eSDaniel Borkmann case BPF_JMP | BPF_JLT | BPF_X: 89762258278SAlexei Starovoitov case BPF_JMP | BPF_JGE | BPF_X: 89852afc51eSDaniel Borkmann case BPF_JMP | BPF_JLE | BPF_X: 89962258278SAlexei Starovoitov case BPF_JMP | BPF_JSGT | BPF_X: 90052afc51eSDaniel Borkmann case BPF_JMP | BPF_JSLT | BPF_X: 90162258278SAlexei Starovoitov case BPF_JMP | BPF_JSGE | BPF_X: 90252afc51eSDaniel Borkmann case BPF_JMP | BPF_JSLE | BPF_X: 903e430f34eSAlexei Starovoitov /* cmp dst_reg, src_reg */ 904e430f34eSAlexei Starovoitov EMIT3(add_2mod(0x48, dst_reg, src_reg), 0x39, 905e430f34eSAlexei Starovoitov add_2reg(0xC0, dst_reg, src_reg)); 90662258278SAlexei Starovoitov goto emit_cond_jmp; 90762258278SAlexei Starovoitov 90862258278SAlexei Starovoitov case BPF_JMP | BPF_JSET | BPF_X: 909e430f34eSAlexei Starovoitov /* test dst_reg, src_reg */ 910e430f34eSAlexei Starovoitov EMIT3(add_2mod(0x48, dst_reg, src_reg), 0x85, 911e430f34eSAlexei Starovoitov add_2reg(0xC0, dst_reg, src_reg)); 91262258278SAlexei Starovoitov goto emit_cond_jmp; 91362258278SAlexei Starovoitov 91462258278SAlexei Starovoitov case BPF_JMP | BPF_JSET | BPF_K: 915e430f34eSAlexei Starovoitov /* test dst_reg, imm32 */ 916e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 917e430f34eSAlexei Starovoitov EMIT2_off32(0xF7, add_1reg(0xC0, dst_reg), imm32); 91862258278SAlexei Starovoitov goto emit_cond_jmp; 91962258278SAlexei Starovoitov 92062258278SAlexei Starovoitov case BPF_JMP | BPF_JEQ | BPF_K: 92162258278SAlexei Starovoitov case BPF_JMP | BPF_JNE | BPF_K: 92262258278SAlexei Starovoitov case BPF_JMP | BPF_JGT | BPF_K: 92352afc51eSDaniel Borkmann case BPF_JMP | BPF_JLT | BPF_K: 92462258278SAlexei Starovoitov case BPF_JMP | BPF_JGE | BPF_K: 92552afc51eSDaniel Borkmann case BPF_JMP | BPF_JLE | BPF_K: 92662258278SAlexei Starovoitov case BPF_JMP | BPF_JSGT | BPF_K: 92752afc51eSDaniel Borkmann case BPF_JMP | BPF_JSLT | BPF_K: 92862258278SAlexei Starovoitov case BPF_JMP | BPF_JSGE | BPF_K: 92952afc51eSDaniel Borkmann case BPF_JMP | BPF_JSLE | BPF_K: 930e430f34eSAlexei Starovoitov /* cmp dst_reg, imm8/32 */ 931e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 93262258278SAlexei Starovoitov 933e430f34eSAlexei Starovoitov if (is_imm8(imm32)) 934e430f34eSAlexei Starovoitov EMIT3(0x83, add_1reg(0xF8, dst_reg), imm32); 93562258278SAlexei Starovoitov else 936e430f34eSAlexei Starovoitov EMIT2_off32(0x81, add_1reg(0xF8, dst_reg), imm32); 93762258278SAlexei Starovoitov 93862258278SAlexei Starovoitov emit_cond_jmp: /* convert BPF opcode to x86 */ 93962258278SAlexei Starovoitov switch (BPF_OP(insn->code)) { 94062258278SAlexei Starovoitov case BPF_JEQ: 94162258278SAlexei Starovoitov jmp_cond = X86_JE; 94262258278SAlexei Starovoitov break; 94362258278SAlexei Starovoitov case BPF_JSET: 94462258278SAlexei Starovoitov case BPF_JNE: 94562258278SAlexei Starovoitov jmp_cond = X86_JNE; 94662258278SAlexei Starovoitov break; 94762258278SAlexei Starovoitov case BPF_JGT: 94862258278SAlexei Starovoitov /* GT is unsigned '>', JA in x86 */ 94962258278SAlexei Starovoitov jmp_cond = X86_JA; 95062258278SAlexei Starovoitov break; 95152afc51eSDaniel Borkmann case BPF_JLT: 95252afc51eSDaniel Borkmann /* LT is unsigned '<', JB in x86 */ 95352afc51eSDaniel Borkmann jmp_cond = X86_JB; 95452afc51eSDaniel Borkmann break; 95562258278SAlexei Starovoitov case BPF_JGE: 95662258278SAlexei Starovoitov /* GE is unsigned '>=', JAE in x86 */ 95762258278SAlexei Starovoitov jmp_cond = X86_JAE; 95862258278SAlexei Starovoitov break; 95952afc51eSDaniel Borkmann case BPF_JLE: 96052afc51eSDaniel Borkmann /* LE is unsigned '<=', JBE in x86 */ 96152afc51eSDaniel Borkmann jmp_cond = X86_JBE; 96252afc51eSDaniel Borkmann break; 96362258278SAlexei Starovoitov case BPF_JSGT: 96462258278SAlexei Starovoitov /* signed '>', GT in x86 */ 96562258278SAlexei Starovoitov jmp_cond = X86_JG; 96662258278SAlexei Starovoitov break; 96752afc51eSDaniel Borkmann case BPF_JSLT: 96852afc51eSDaniel Borkmann /* signed '<', LT in x86 */ 96952afc51eSDaniel Borkmann jmp_cond = X86_JL; 97052afc51eSDaniel Borkmann break; 97162258278SAlexei Starovoitov case BPF_JSGE: 97262258278SAlexei Starovoitov /* signed '>=', GE in x86 */ 97362258278SAlexei Starovoitov jmp_cond = X86_JGE; 97462258278SAlexei Starovoitov break; 97552afc51eSDaniel Borkmann case BPF_JSLE: 97652afc51eSDaniel Borkmann /* signed '<=', LE in x86 */ 97752afc51eSDaniel Borkmann jmp_cond = X86_JLE; 97852afc51eSDaniel Borkmann break; 97962258278SAlexei Starovoitov default: /* to silence gcc warning */ 98062258278SAlexei Starovoitov return -EFAULT; 98162258278SAlexei Starovoitov } 98262258278SAlexei Starovoitov jmp_offset = addrs[i + insn->off] - addrs[i]; 98362258278SAlexei Starovoitov if (is_imm8(jmp_offset)) { 98462258278SAlexei Starovoitov EMIT2(jmp_cond, jmp_offset); 98562258278SAlexei Starovoitov } else if (is_simm32(jmp_offset)) { 98662258278SAlexei Starovoitov EMIT2_off32(0x0F, jmp_cond + 0x10, jmp_offset); 9873b58908aSEric Dumazet } else { 98862258278SAlexei Starovoitov pr_err("cond_jmp gen bug %llx\n", jmp_offset); 98962258278SAlexei Starovoitov return -EFAULT; 9903b58908aSEric Dumazet } 99162258278SAlexei Starovoitov 9923b58908aSEric Dumazet break; 99362258278SAlexei Starovoitov 99462258278SAlexei Starovoitov case BPF_JMP | BPF_JA: 99562258278SAlexei Starovoitov jmp_offset = addrs[i + insn->off] - addrs[i]; 99662258278SAlexei Starovoitov if (!jmp_offset) 99762258278SAlexei Starovoitov /* optimize out nop jumps */ 99862258278SAlexei Starovoitov break; 99962258278SAlexei Starovoitov emit_jmp: 100062258278SAlexei Starovoitov if (is_imm8(jmp_offset)) { 100162258278SAlexei Starovoitov EMIT2(0xEB, jmp_offset); 100262258278SAlexei Starovoitov } else if (is_simm32(jmp_offset)) { 100362258278SAlexei Starovoitov EMIT1_off32(0xE9, jmp_offset); 100462258278SAlexei Starovoitov } else { 100562258278SAlexei Starovoitov pr_err("jmp gen bug %llx\n", jmp_offset); 100662258278SAlexei Starovoitov return -EFAULT; 10073b58908aSEric Dumazet } 100862258278SAlexei Starovoitov break; 100962258278SAlexei Starovoitov 101062258278SAlexei Starovoitov case BPF_LD | BPF_IND | BPF_W: 101162258278SAlexei Starovoitov func = sk_load_word; 101262258278SAlexei Starovoitov goto common_load; 101362258278SAlexei Starovoitov case BPF_LD | BPF_ABS | BPF_W: 1014e430f34eSAlexei Starovoitov func = CHOOSE_LOAD_FUNC(imm32, sk_load_word); 1015e0ee9c12SAlexei Starovoitov common_load: 1016e0ee9c12SAlexei Starovoitov ctx->seen_ld_abs = seen_ld_abs = true; 101762258278SAlexei Starovoitov jmp_offset = func - (image + addrs[i]); 101862258278SAlexei Starovoitov if (!func || !is_simm32(jmp_offset)) { 101962258278SAlexei Starovoitov pr_err("unsupported bpf func %d addr %p image %p\n", 1020e430f34eSAlexei Starovoitov imm32, func, image); 102162258278SAlexei Starovoitov return -EINVAL; 102262258278SAlexei Starovoitov } 102362258278SAlexei Starovoitov if (BPF_MODE(insn->code) == BPF_ABS) { 102462258278SAlexei Starovoitov /* mov %esi, imm32 */ 1025e430f34eSAlexei Starovoitov EMIT1_off32(0xBE, imm32); 102662258278SAlexei Starovoitov } else { 1027e430f34eSAlexei Starovoitov /* mov %rsi, src_reg */ 1028e430f34eSAlexei Starovoitov EMIT_mov(BPF_REG_2, src_reg); 1029e430f34eSAlexei Starovoitov if (imm32) { 1030e430f34eSAlexei Starovoitov if (is_imm8(imm32)) 103162258278SAlexei Starovoitov /* add %esi, imm8 */ 1032e430f34eSAlexei Starovoitov EMIT3(0x83, 0xC6, imm32); 103362258278SAlexei Starovoitov else 103462258278SAlexei Starovoitov /* add %esi, imm32 */ 1035e430f34eSAlexei Starovoitov EMIT2_off32(0x81, 0xC6, imm32); 103662258278SAlexei Starovoitov } 103762258278SAlexei Starovoitov } 103862258278SAlexei Starovoitov /* skb pointer is in R6 (%rbx), it will be copied into 103962258278SAlexei Starovoitov * %rdi if skb_copy_bits() call is necessary. 104062258278SAlexei Starovoitov * sk_load_* helpers also use %r10 and %r9d. 104162258278SAlexei Starovoitov * See bpf_jit.S 104262258278SAlexei Starovoitov */ 1043959a7579SDaniel Borkmann if (seen_ax_reg) 1044959a7579SDaniel Borkmann /* r10 = skb->data, mov %r10, off32(%rbx) */ 1045959a7579SDaniel Borkmann EMIT3_off32(0x4c, 0x8b, 0x93, 1046959a7579SDaniel Borkmann offsetof(struct sk_buff, data)); 104762258278SAlexei Starovoitov EMIT1_off32(0xE8, jmp_offset); /* call */ 10480a14842fSEric Dumazet break; 104962258278SAlexei Starovoitov 105062258278SAlexei Starovoitov case BPF_LD | BPF_IND | BPF_H: 105162258278SAlexei Starovoitov func = sk_load_half; 105262258278SAlexei Starovoitov goto common_load; 105362258278SAlexei Starovoitov case BPF_LD | BPF_ABS | BPF_H: 1054e430f34eSAlexei Starovoitov func = CHOOSE_LOAD_FUNC(imm32, sk_load_half); 10550a14842fSEric Dumazet goto common_load; 105662258278SAlexei Starovoitov case BPF_LD | BPF_IND | BPF_B: 105762258278SAlexei Starovoitov func = sk_load_byte; 105862258278SAlexei Starovoitov goto common_load; 105962258278SAlexei Starovoitov case BPF_LD | BPF_ABS | BPF_B: 1060e430f34eSAlexei Starovoitov func = CHOOSE_LOAD_FUNC(imm32, sk_load_byte); 10610a14842fSEric Dumazet goto common_load; 10620a14842fSEric Dumazet 106362258278SAlexei Starovoitov case BPF_JMP | BPF_EXIT: 1064769e0de6SAlexei Starovoitov if (seen_exit) { 106562258278SAlexei Starovoitov jmp_offset = ctx->cleanup_addr - addrs[i]; 106662258278SAlexei Starovoitov goto emit_jmp; 106762258278SAlexei Starovoitov } 1068769e0de6SAlexei Starovoitov seen_exit = true; 106962258278SAlexei Starovoitov /* update cleanup_addr */ 107062258278SAlexei Starovoitov ctx->cleanup_addr = proglen; 1071177366bfSAlexei Starovoitov /* mov rbx, qword ptr [rbp+0] */ 1072177366bfSAlexei Starovoitov EMIT4(0x48, 0x8B, 0x5D, 0); 1073177366bfSAlexei Starovoitov /* mov r13, qword ptr [rbp+8] */ 1074177366bfSAlexei Starovoitov EMIT4(0x4C, 0x8B, 0x6D, 8); 1075177366bfSAlexei Starovoitov /* mov r14, qword ptr [rbp+16] */ 1076177366bfSAlexei Starovoitov EMIT4(0x4C, 0x8B, 0x75, 16); 1077177366bfSAlexei Starovoitov /* mov r15, qword ptr [rbp+24] */ 1078177366bfSAlexei Starovoitov EMIT4(0x4C, 0x8B, 0x7D, 24); 10790a14842fSEric Dumazet 1080177366bfSAlexei Starovoitov /* add rbp, AUX_STACK_SPACE */ 1081177366bfSAlexei Starovoitov EMIT4(0x48, 0x83, 0xC5, AUX_STACK_SPACE); 108262258278SAlexei Starovoitov EMIT1(0xC9); /* leave */ 108362258278SAlexei Starovoitov EMIT1(0xC3); /* ret */ 10840a14842fSEric Dumazet break; 10850a14842fSEric Dumazet 10860a14842fSEric Dumazet default: 108762258278SAlexei Starovoitov /* By design x64 JIT should support all BPF instructions 108862258278SAlexei Starovoitov * This error will be seen if new instruction was added 108962258278SAlexei Starovoitov * to interpreter, but not to JIT 10907ae457c1SAlexei Starovoitov * or if there is junk in bpf_prog 109162258278SAlexei Starovoitov */ 109262258278SAlexei Starovoitov pr_err("bpf_jit: unknown opcode %02x\n", insn->code); 1093f3c2af7bSAlexei Starovoitov return -EINVAL; 10940a14842fSEric Dumazet } 109562258278SAlexei Starovoitov 10960a14842fSEric Dumazet ilen = prog - temp; 1097e0ee9c12SAlexei Starovoitov if (ilen > BPF_MAX_INSN_SIZE) { 10989383191dSDaniel Borkmann pr_err("bpf_jit: fatal insn size error\n"); 1099e0ee9c12SAlexei Starovoitov return -EFAULT; 1100e0ee9c12SAlexei Starovoitov } 1101e0ee9c12SAlexei Starovoitov 11020a14842fSEric Dumazet if (image) { 11030a14842fSEric Dumazet if (unlikely(proglen + ilen > oldproglen)) { 11049383191dSDaniel Borkmann pr_err("bpf_jit: fatal error\n"); 1105f3c2af7bSAlexei Starovoitov return -EFAULT; 11060a14842fSEric Dumazet } 11070a14842fSEric Dumazet memcpy(image + proglen, temp, ilen); 11080a14842fSEric Dumazet } 11090a14842fSEric Dumazet proglen += ilen; 11100a14842fSEric Dumazet addrs[i] = proglen; 11110a14842fSEric Dumazet prog = temp; 11120a14842fSEric Dumazet } 1113f3c2af7bSAlexei Starovoitov return proglen; 1114f3c2af7bSAlexei Starovoitov } 1115f3c2af7bSAlexei Starovoitov 11161c2a088aSAlexei Starovoitov struct x64_jit_data { 11171c2a088aSAlexei Starovoitov struct bpf_binary_header *header; 11181c2a088aSAlexei Starovoitov int *addrs; 11191c2a088aSAlexei Starovoitov u8 *image; 11201c2a088aSAlexei Starovoitov int proglen; 11211c2a088aSAlexei Starovoitov struct jit_context ctx; 11221c2a088aSAlexei Starovoitov }; 11231c2a088aSAlexei Starovoitov 1124d1c55ab5SDaniel Borkmann struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) 112562258278SAlexei Starovoitov { 1126f3c2af7bSAlexei Starovoitov struct bpf_binary_header *header = NULL; 1127959a7579SDaniel Borkmann struct bpf_prog *tmp, *orig_prog = prog; 11281c2a088aSAlexei Starovoitov struct x64_jit_data *jit_data; 1129f3c2af7bSAlexei Starovoitov int proglen, oldproglen = 0; 1130f3c2af7bSAlexei Starovoitov struct jit_context ctx = {}; 1131959a7579SDaniel Borkmann bool tmp_blinded = false; 11321c2a088aSAlexei Starovoitov bool extra_pass = false; 1133f3c2af7bSAlexei Starovoitov u8 *image = NULL; 1134f3c2af7bSAlexei Starovoitov int *addrs; 1135f3c2af7bSAlexei Starovoitov int pass; 1136f3c2af7bSAlexei Starovoitov int i; 1137f3c2af7bSAlexei Starovoitov 113860b58afcSAlexei Starovoitov if (!prog->jit_requested) 1139959a7579SDaniel Borkmann return orig_prog; 1140959a7579SDaniel Borkmann 1141959a7579SDaniel Borkmann tmp = bpf_jit_blind_constants(prog); 1142959a7579SDaniel Borkmann /* If blinding was requested and we failed during blinding, 1143959a7579SDaniel Borkmann * we must fall back to the interpreter. 1144959a7579SDaniel Borkmann */ 1145959a7579SDaniel Borkmann if (IS_ERR(tmp)) 1146959a7579SDaniel Borkmann return orig_prog; 1147959a7579SDaniel Borkmann if (tmp != prog) { 1148959a7579SDaniel Borkmann tmp_blinded = true; 1149959a7579SDaniel Borkmann prog = tmp; 1150959a7579SDaniel Borkmann } 1151f3c2af7bSAlexei Starovoitov 11521c2a088aSAlexei Starovoitov jit_data = prog->aux->jit_data; 11531c2a088aSAlexei Starovoitov if (!jit_data) { 11541c2a088aSAlexei Starovoitov jit_data = kzalloc(sizeof(*jit_data), GFP_KERNEL); 11551c2a088aSAlexei Starovoitov if (!jit_data) { 11561c2a088aSAlexei Starovoitov prog = orig_prog; 11571c2a088aSAlexei Starovoitov goto out; 11581c2a088aSAlexei Starovoitov } 11591c2a088aSAlexei Starovoitov prog->aux->jit_data = jit_data; 11601c2a088aSAlexei Starovoitov } 11611c2a088aSAlexei Starovoitov addrs = jit_data->addrs; 11621c2a088aSAlexei Starovoitov if (addrs) { 11631c2a088aSAlexei Starovoitov ctx = jit_data->ctx; 11641c2a088aSAlexei Starovoitov oldproglen = jit_data->proglen; 11651c2a088aSAlexei Starovoitov image = jit_data->image; 11661c2a088aSAlexei Starovoitov header = jit_data->header; 11671c2a088aSAlexei Starovoitov extra_pass = true; 11681c2a088aSAlexei Starovoitov goto skip_init_addrs; 11691c2a088aSAlexei Starovoitov } 1170f3c2af7bSAlexei Starovoitov addrs = kmalloc(prog->len * sizeof(*addrs), GFP_KERNEL); 1171959a7579SDaniel Borkmann if (!addrs) { 1172959a7579SDaniel Borkmann prog = orig_prog; 11731c2a088aSAlexei Starovoitov goto out_addrs; 1174959a7579SDaniel Borkmann } 1175f3c2af7bSAlexei Starovoitov 1176f3c2af7bSAlexei Starovoitov /* Before first pass, make a rough estimation of addrs[] 1177f3c2af7bSAlexei Starovoitov * each bpf instruction is translated to less than 64 bytes 1178f3c2af7bSAlexei Starovoitov */ 1179f3c2af7bSAlexei Starovoitov for (proglen = 0, i = 0; i < prog->len; i++) { 1180f3c2af7bSAlexei Starovoitov proglen += 64; 1181f3c2af7bSAlexei Starovoitov addrs[i] = proglen; 1182f3c2af7bSAlexei Starovoitov } 1183f3c2af7bSAlexei Starovoitov ctx.cleanup_addr = proglen; 11841c2a088aSAlexei Starovoitov skip_init_addrs: 1185f3c2af7bSAlexei Starovoitov 11863f7352bfSAlexei Starovoitov /* JITed image shrinks with every pass and the loop iterates 11873f7352bfSAlexei Starovoitov * until the image stops shrinking. Very large bpf programs 11883f7352bfSAlexei Starovoitov * may converge on the last pass. In such case do one more 11893f7352bfSAlexei Starovoitov * pass to emit the final image 11903f7352bfSAlexei Starovoitov */ 11913f7352bfSAlexei Starovoitov for (pass = 0; pass < 10 || image; pass++) { 1192f3c2af7bSAlexei Starovoitov proglen = do_jit(prog, addrs, image, oldproglen, &ctx); 1193f3c2af7bSAlexei Starovoitov if (proglen <= 0) { 1194f3c2af7bSAlexei Starovoitov image = NULL; 1195f3c2af7bSAlexei Starovoitov if (header) 1196738cbe72SDaniel Borkmann bpf_jit_binary_free(header); 1197959a7579SDaniel Borkmann prog = orig_prog; 1198959a7579SDaniel Borkmann goto out_addrs; 1199f3c2af7bSAlexei Starovoitov } 12000a14842fSEric Dumazet if (image) { 1201e0ee9c12SAlexei Starovoitov if (proglen != oldproglen) { 1202f3c2af7bSAlexei Starovoitov pr_err("bpf_jit: proglen=%d != oldproglen=%d\n", 1203f3c2af7bSAlexei Starovoitov proglen, oldproglen); 1204959a7579SDaniel Borkmann prog = orig_prog; 1205959a7579SDaniel Borkmann goto out_addrs; 1206e0ee9c12SAlexei Starovoitov } 12070a14842fSEric Dumazet break; 12080a14842fSEric Dumazet } 12090a14842fSEric Dumazet if (proglen == oldproglen) { 1210738cbe72SDaniel Borkmann header = bpf_jit_binary_alloc(proglen, &image, 1211738cbe72SDaniel Borkmann 1, jit_fill_hole); 1212959a7579SDaniel Borkmann if (!header) { 1213959a7579SDaniel Borkmann prog = orig_prog; 1214959a7579SDaniel Borkmann goto out_addrs; 1215959a7579SDaniel Borkmann } 12160a14842fSEric Dumazet } 12170a14842fSEric Dumazet oldproglen = proglen; 12180a14842fSEric Dumazet } 121979617801SDaniel Borkmann 12200a14842fSEric Dumazet if (bpf_jit_enable > 1) 1221485d6511SDaniel Borkmann bpf_jit_dump(prog->len, proglen, pass + 1, image); 12220a14842fSEric Dumazet 12230a14842fSEric Dumazet if (image) { 1224314beb9bSEric Dumazet bpf_flush_icache(header, image + proglen); 12251c2a088aSAlexei Starovoitov if (!prog->is_func || extra_pass) { 12269d876e79SDaniel Borkmann bpf_jit_binary_lock_ro(header); 12271c2a088aSAlexei Starovoitov } else { 12281c2a088aSAlexei Starovoitov jit_data->addrs = addrs; 12291c2a088aSAlexei Starovoitov jit_data->ctx = ctx; 12301c2a088aSAlexei Starovoitov jit_data->proglen = proglen; 12311c2a088aSAlexei Starovoitov jit_data->image = image; 12321c2a088aSAlexei Starovoitov jit_data->header = header; 12331c2a088aSAlexei Starovoitov } 1234f3c2af7bSAlexei Starovoitov prog->bpf_func = (void *)image; 1235a91263d5SDaniel Borkmann prog->jited = 1; 1236783d28ddSMartin KaFai Lau prog->jited_len = proglen; 12379d5ecb09SDaniel Borkmann } else { 12389d5ecb09SDaniel Borkmann prog = orig_prog; 12390a14842fSEric Dumazet } 1240959a7579SDaniel Borkmann 12411c2a088aSAlexei Starovoitov if (!prog->is_func || extra_pass) { 1242959a7579SDaniel Borkmann out_addrs: 12430a14842fSEric Dumazet kfree(addrs); 12441c2a088aSAlexei Starovoitov kfree(jit_data); 12451c2a088aSAlexei Starovoitov prog->aux->jit_data = NULL; 12461c2a088aSAlexei Starovoitov } 1247959a7579SDaniel Borkmann out: 1248959a7579SDaniel Borkmann if (tmp_blinded) 1249959a7579SDaniel Borkmann bpf_jit_prog_release_other(prog, prog == orig_prog ? 1250959a7579SDaniel Borkmann tmp : orig_prog); 1251d1c55ab5SDaniel Borkmann return prog; 12520a14842fSEric Dumazet } 1253