1 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
2 * Copyright (c) 2016 Facebook
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of version 2 of the GNU General Public
6 * License as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
14 #include <linux/bpf.h>
18 #define __BPF_FUNC_STR_FN(x) [BPF_FUNC_ ## x] = __stringify(bpf_ ## x)
19 static const char * const func_id_str[] = {
20 __BPF_FUNC_MAPPER(__BPF_FUNC_STR_FN)
22 #undef __BPF_FUNC_STR_FN
24 static const char *__func_get_name(const struct bpf_insn_cbs *cbs,
25 const struct bpf_insn *insn,
26 char *buff, size_t len)
28 BUILD_BUG_ON(ARRAY_SIZE(func_id_str) != __BPF_FUNC_MAX_ID);
30 if (insn->src_reg != BPF_PSEUDO_CALL &&
31 insn->imm >= 0 && insn->imm < __BPF_FUNC_MAX_ID &&
32 func_id_str[insn->imm])
33 return func_id_str[insn->imm];
35 if (cbs && cbs->cb_call)
36 return cbs->cb_call(cbs->private_data, insn);
38 if (insn->src_reg == BPF_PSEUDO_CALL)
39 snprintf(buff, len, "%+d", insn->imm);
44 static const char *__func_imm_name(const struct bpf_insn_cbs *cbs,
45 const struct bpf_insn *insn,
46 u64 full_imm, char *buff, size_t len)
48 if (cbs && cbs->cb_imm)
49 return cbs->cb_imm(cbs->private_data, insn, full_imm);
51 snprintf(buff, len, "0x%llx", (unsigned long long)full_imm);
55 const char *func_id_name(int id)
57 if (id >= 0 && id < __BPF_FUNC_MAX_ID && func_id_str[id])
58 return func_id_str[id];
63 const char *const bpf_class_string[8] = {
71 [BPF_ALU64] = "alu64",
74 const char *const bpf_alu_string[16] = {
75 [BPF_ADD >> 4] = "+=",
76 [BPF_SUB >> 4] = "-=",
77 [BPF_MUL >> 4] = "*=",
78 [BPF_DIV >> 4] = "/=",
80 [BPF_AND >> 4] = "&=",
81 [BPF_LSH >> 4] = "<<=",
82 [BPF_RSH >> 4] = ">>=",
83 [BPF_NEG >> 4] = "neg",
84 [BPF_MOD >> 4] = "%=",
85 [BPF_XOR >> 4] = "^=",
87 [BPF_ARSH >> 4] = "s>>=",
88 [BPF_END >> 4] = "endian",
91 static const char *const bpf_ldst_string[] = {
95 [BPF_DW >> 3] = "u64",
98 static const char *const bpf_jmp_string[16] = {
99 [BPF_JA >> 4] = "jmp",
100 [BPF_JEQ >> 4] = "==",
101 [BPF_JGT >> 4] = ">",
102 [BPF_JLT >> 4] = "<",
103 [BPF_JGE >> 4] = ">=",
104 [BPF_JLE >> 4] = "<=",
105 [BPF_JSET >> 4] = "&",
106 [BPF_JNE >> 4] = "!=",
107 [BPF_JSGT >> 4] = "s>",
108 [BPF_JSLT >> 4] = "s<",
109 [BPF_JSGE >> 4] = "s>=",
110 [BPF_JSLE >> 4] = "s<=",
111 [BPF_CALL >> 4] = "call",
112 [BPF_EXIT >> 4] = "exit",
115 static void print_bpf_end_insn(bpf_insn_print_t verbose,
117 const struct bpf_insn *insn)
119 verbose(private_data, "(%02x) r%d = %s%d r%d\n",
120 insn->code, insn->dst_reg,
121 BPF_SRC(insn->code) == BPF_TO_BE ? "be" : "le",
122 insn->imm, insn->dst_reg);
125 void print_bpf_insn(const struct bpf_insn_cbs *cbs,
126 const struct bpf_insn *insn,
127 bool allow_ptr_leaks)
129 const bpf_insn_print_t verbose = cbs->cb_print;
130 u8 class = BPF_CLASS(insn->code);
132 if (class == BPF_ALU || class == BPF_ALU64) {
133 if (BPF_OP(insn->code) == BPF_END) {
134 if (class == BPF_ALU64)
135 verbose(cbs->private_data, "BUG_alu64_%02x\n", insn->code);
137 print_bpf_end_insn(verbose, cbs->private_data, insn);
138 } else if (BPF_OP(insn->code) == BPF_NEG) {
139 verbose(cbs->private_data, "(%02x) r%d = %s-r%d\n",
140 insn->code, insn->dst_reg,
141 class == BPF_ALU ? "(u32) " : "",
143 } else if (BPF_SRC(insn->code) == BPF_X) {
144 verbose(cbs->private_data, "(%02x) %sr%d %s %sr%d\n",
145 insn->code, class == BPF_ALU ? "(u32) " : "",
147 bpf_alu_string[BPF_OP(insn->code) >> 4],
148 class == BPF_ALU ? "(u32) " : "",
151 verbose(cbs->private_data, "(%02x) %sr%d %s %s%d\n",
152 insn->code, class == BPF_ALU ? "(u32) " : "",
154 bpf_alu_string[BPF_OP(insn->code) >> 4],
155 class == BPF_ALU ? "(u32) " : "",
158 } else if (class == BPF_STX) {
159 if (BPF_MODE(insn->code) == BPF_MEM)
160 verbose(cbs->private_data, "(%02x) *(%s *)(r%d %+d) = r%d\n",
162 bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
164 insn->off, insn->src_reg);
165 else if (BPF_MODE(insn->code) == BPF_XADD)
166 verbose(cbs->private_data, "(%02x) lock *(%s *)(r%d %+d) += r%d\n",
168 bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
169 insn->dst_reg, insn->off,
172 verbose(cbs->private_data, "BUG_%02x\n", insn->code);
173 } else if (class == BPF_ST) {
174 if (BPF_MODE(insn->code) == BPF_MEM) {
175 verbose(cbs->private_data, "(%02x) *(%s *)(r%d %+d) = %d\n",
177 bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
179 insn->off, insn->imm);
180 } else if (BPF_MODE(insn->code) == 0xc0 /* BPF_NOSPEC, no UAPI */) {
181 verbose(cbs->private_data, "(%02x) nospec\n", insn->code);
183 verbose(cbs->private_data, "BUG_st_%02x\n", insn->code);
185 } else if (class == BPF_LDX) {
186 if (BPF_MODE(insn->code) != BPF_MEM) {
187 verbose(cbs->private_data, "BUG_ldx_%02x\n", insn->code);
190 verbose(cbs->private_data, "(%02x) r%d = *(%s *)(r%d %+d)\n",
191 insn->code, insn->dst_reg,
192 bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
193 insn->src_reg, insn->off);
194 } else if (class == BPF_LD) {
195 if (BPF_MODE(insn->code) == BPF_ABS) {
196 verbose(cbs->private_data, "(%02x) r0 = *(%s *)skb[%d]\n",
198 bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
200 } else if (BPF_MODE(insn->code) == BPF_IND) {
201 verbose(cbs->private_data, "(%02x) r0 = *(%s *)skb[r%d + %d]\n",
203 bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
204 insn->src_reg, insn->imm);
205 } else if (BPF_MODE(insn->code) == BPF_IMM &&
206 BPF_SIZE(insn->code) == BPF_DW) {
207 /* At this point, we already made sure that the second
208 * part of the ldimm64 insn is accessible.
210 u64 imm = ((u64)(insn + 1)->imm << 32) | (u32)insn->imm;
211 bool map_ptr = insn->src_reg == BPF_PSEUDO_MAP_FD;
214 if (map_ptr && !allow_ptr_leaks)
217 verbose(cbs->private_data, "(%02x) r%d = %s\n",
218 insn->code, insn->dst_reg,
219 __func_imm_name(cbs, insn, imm,
222 verbose(cbs->private_data, "BUG_ld_%02x\n", insn->code);
225 } else if (class == BPF_JMP) {
226 u8 opcode = BPF_OP(insn->code);
228 if (opcode == BPF_CALL) {
231 if (insn->src_reg == BPF_PSEUDO_CALL) {
232 verbose(cbs->private_data, "(%02x) call pc%s\n",
234 __func_get_name(cbs, insn,
237 strcpy(tmp, "unknown");
238 verbose(cbs->private_data, "(%02x) call %s#%d\n", insn->code,
239 __func_get_name(cbs, insn,
243 } else if (insn->code == (BPF_JMP | BPF_JA)) {
244 verbose(cbs->private_data, "(%02x) goto pc%+d\n",
245 insn->code, insn->off);
246 } else if (insn->code == (BPF_JMP | BPF_EXIT)) {
247 verbose(cbs->private_data, "(%02x) exit\n", insn->code);
248 } else if (BPF_SRC(insn->code) == BPF_X) {
249 verbose(cbs->private_data, "(%02x) if r%d %s r%d goto pc%+d\n",
250 insn->code, insn->dst_reg,
251 bpf_jmp_string[BPF_OP(insn->code) >> 4],
252 insn->src_reg, insn->off);
254 verbose(cbs->private_data, "(%02x) if r%d %s 0x%x goto pc%+d\n",
255 insn->code, insn->dst_reg,
256 bpf_jmp_string[BPF_OP(insn->code) >> 4],
257 insn->imm, insn->off);
260 verbose(cbs->private_data, "(%02x) %s\n",
261 insn->code, bpf_class_string[class]);