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// SPDX-License-Identifier: GPL-2.0-only/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com * Copyright (c) 2016 Facebook */ #include <linux/bpf.h> #include "disasm.h" #define __BPF_FUNC_STR_FN(x) [BPF_FUNC_ ## x] = __stringify(bpf_ ## x)static const char * const func_id_str[] = {	__BPF_FUNC_MAPPER(__BPF_FUNC_STR_FN)};#undef __BPF_FUNC_STR_FN static const char *__func_get_name(const struct bpf_insn_cbs *cbs,				   const struct bpf_insn *insn,				   char *buff, size_t len){	BUILD_BUG_ON(ARRAY_SIZE(func_id_str) != __BPF_FUNC_MAX_ID); 	if (!insn->src_reg &&	    insn->imm >= 0 && insn->imm < __BPF_FUNC_MAX_ID &&	    func_id_str[insn->imm])		return func_id_str[insn->imm]; 	if (cbs && cbs->cb_call) {		const char *res; 		res = cbs->cb_call(cbs->private_data, insn);		if (res)			return res;	} 	if (insn->src_reg == BPF_PSEUDO_CALL)		snprintf(buff, len, "%+d", insn->imm);	else if (insn->src_reg == BPF_PSEUDO_KFUNC_CALL)		snprintf(buff, len, "kernel-function"); 	return buff;} static const char *__func_imm_name(const struct bpf_insn_cbs *cbs,				   const struct bpf_insn *insn,				   u64 full_imm, char *buff, size_t len){	if (cbs && cbs->cb_imm)		return cbs->cb_imm(cbs->private_data, insn, full_imm); 	snprintf(buff, len, "0x%llx", (unsigned long long)full_imm);	return buff;} const char *func_id_name(int id){	if (id >= 0 && id < __BPF_FUNC_MAX_ID && func_id_str[id])		return func_id_str[id];	else		return "unknown";} const char *const bpf_class_string[8] = {	[BPF_LD]    = "ld",	[BPF_LDX]   = "ldx",	[BPF_ST]    = "st",	[BPF_STX]   = "stx",	[BPF_ALU]   = "alu",	[BPF_JMP]   = "jmp",	[BPF_JMP32] = "jmp32",	[BPF_ALU64] = "alu64",}; const char *const bpf_alu_string[16] = {	[BPF_ADD >> 4]  = "+=",	[BPF_SUB >> 4]  = "-=",	[BPF_MUL >> 4]  = "*=",	[BPF_DIV >> 4]  = "/=",	[BPF_OR  >> 4]  = "|=",	[BPF_AND >> 4]  = "&=",	[BPF_LSH >> 4]  = "<<=",	[BPF_RSH >> 4]  = ">>=",	[BPF_NEG >> 4]  = "neg",	[BPF_MOD >> 4]  = "%=",	[BPF_XOR >> 4]  = "^=",	[BPF_MOV >> 4]  = "=",	[BPF_ARSH >> 4] = "s>>=",	[BPF_END >> 4]  = "endian",}; static const char *const bpf_atomic_alu_string[16] = {	[BPF_ADD >> 4]  = "add",	[BPF_AND >> 4]  = "and",	[BPF_OR >> 4]  = "or",	[BPF_XOR >> 4]  = "xor",}; static const char *const bpf_ldst_string[] = {	[BPF_W >> 3]  = "u32",	[BPF_H >> 3]  = "u16",	[BPF_B >> 3]  = "u8",	[BPF_DW >> 3] = "u64",}; static const char *const bpf_jmp_string[16] = {	[BPF_JA >> 4]   = "jmp",	[BPF_JEQ >> 4]  = "==",	[BPF_JGT >> 4]  = ">",	[BPF_JLT >> 4]  = "<",	[BPF_JGE >> 4]  = ">=",	[BPF_JLE >> 4]  = "<=",	[BPF_JSET >> 4] = "&",	[BPF_JNE >> 4]  = "!=",	[BPF_JSGT >> 4] = "s>",	[BPF_JSLT >> 4] = "s<",	[BPF_JSGE >> 4] = "s>=",	[BPF_JSLE >> 4] = "s<=",	[BPF_CALL >> 4] = "call",	[BPF_EXIT >> 4] = "exit",}; static void print_bpf_end_insn(bpf_insn_print_t verbose,			       void *private_data,			       const struct bpf_insn *insn){	verbose(private_data, "(%02x) r%d = %s%d r%d\n",		insn->code, insn->dst_reg,		BPF_SRC(insn->code) == BPF_TO_BE ? "be" : "le",		insn->imm, insn->dst_reg);} void print_bpf_insn(const struct bpf_insn_cbs *cbs,		    const struct bpf_insn *insn,		    bool allow_ptr_leaks){	const bpf_insn_print_t verbose = cbs->cb_print;	u8 class = BPF_CLASS(insn->code); 	if (class == BPF_ALU || class == BPF_ALU64) {		if (BPF_OP(insn->code) == BPF_END) {			if (class == BPF_ALU64)				verbose(cbs->private_data, "BUG_alu64_%02x\n", insn->code);			else				print_bpf_end_insn(verbose, cbs->private_data, insn);		} else if (BPF_OP(insn->code) == BPF_NEG) {			verbose(cbs->private_data, "(%02x) %c%d = -%c%d\n",				insn->code, class == BPF_ALU ? 'w' : 'r',				insn->dst_reg, class == BPF_ALU ? 'w' : 'r',				insn->dst_reg);		} else if (BPF_SRC(insn->code) == BPF_X) {			verbose(cbs->private_data, "(%02x) %c%d %s %c%d\n",				insn->code, class == BPF_ALU ? 'w' : 'r',				insn->dst_reg,				bpf_alu_string[BPF_OP(insn->code) >> 4],				class == BPF_ALU ? 'w' : 'r',				insn->src_reg);		} else {			verbose(cbs->private_data, "(%02x) %c%d %s %d\n",				insn->code, class == BPF_ALU ? 'w' : 'r',				insn->dst_reg,				bpf_alu_string[BPF_OP(insn->code) >> 4],				insn->imm);		}	} else if (class == BPF_STX) {		if (BPF_MODE(insn->code) == BPF_MEM)			verbose(cbs->private_data, "(%02x) *(%s *)(r%d %+d) = r%d\n",				insn->code,				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],				insn->dst_reg,				insn->off, insn->src_reg);		else if (BPF_MODE(insn->code) == BPF_ATOMIC &&			 (insn->imm == BPF_ADD || insn->imm == BPF_AND ||			  insn->imm == BPF_OR || insn->imm == BPF_XOR)) {			verbose(cbs->private_data, "(%02x) lock *(%s *)(r%d %+d) %s r%d\n",				insn->code,				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],				insn->dst_reg, insn->off,				bpf_alu_string[BPF_OP(insn->imm) >> 4],				insn->src_reg);		} else if (BPF_MODE(insn->code) == BPF_ATOMIC &&			   (insn->imm == (BPF_ADD | BPF_FETCH) ||			    insn->imm == (BPF_AND | BPF_FETCH) ||			    insn->imm == (BPF_OR | BPF_FETCH) ||			    insn->imm == (BPF_XOR | BPF_FETCH))) {			verbose(cbs->private_data, "(%02x) r%d = atomic%s_fetch_%s((%s *)(r%d %+d), r%d)\n",				insn->code, insn->src_reg,				BPF_SIZE(insn->code) == BPF_DW ? "64" : "",				bpf_atomic_alu_string[BPF_OP(insn->imm) >> 4],				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],				insn->dst_reg, insn->off, insn->src_reg);		} else if (BPF_MODE(insn->code) == BPF_ATOMIC &&			   insn->imm == BPF_CMPXCHG) {			verbose(cbs->private_data, "(%02x) r0 = atomic%s_cmpxchg((%s *)(r%d %+d), r0, r%d)\n",				insn->code,				BPF_SIZE(insn->code) == BPF_DW ? "64" : "",				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],				insn->dst_reg, insn->off,				insn->src_reg);		} else if (BPF_MODE(insn->code) == BPF_ATOMIC &&			   insn->imm == BPF_XCHG) {			verbose(cbs->private_data, "(%02x) r%d = atomic%s_xchg((%s *)(r%d %+d), r%d)\n",				insn->code, insn->src_reg,				BPF_SIZE(insn->code) == BPF_DW ? "64" : "",				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],				insn->dst_reg, insn->off, insn->src_reg);		} else {			verbose(cbs->private_data, "BUG_%02x\n", insn->code);		}	} else if (class == BPF_ST) {		if (BPF_MODE(insn->code) != BPF_MEM) {			verbose(cbs->private_data, "BUG_st_%02x\n", insn->code);			return;		}		verbose(cbs->private_data, "(%02x) *(%s *)(r%d %+d) = %d\n",			insn->code,			bpf_ldst_string[BPF_SIZE(insn->code) >> 3],			insn->dst_reg,			insn->off, insn->imm);	} else if (class == BPF_LDX) {		if (BPF_MODE(insn->code) != BPF_MEM) {			verbose(cbs->private_data, "BUG_ldx_%02x\n", insn->code);			return;		}		verbose(cbs->private_data, "(%02x) r%d = *(%s *)(r%d %+d)\n",			insn->code, insn->dst_reg,			bpf_ldst_string[BPF_SIZE(insn->code) >> 3],			insn->src_reg, insn->off);	} else if (class == BPF_LD) {		if (BPF_MODE(insn->code) == BPF_ABS) {			verbose(cbs->private_data, "(%02x) r0 = *(%s *)skb[%d]\n",				insn->code,				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],				insn->imm);		} else if (BPF_MODE(insn->code) == BPF_IND) {			verbose(cbs->private_data, "(%02x) r0 = *(%s *)skb[r%d + %d]\n",				insn->code,				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],				insn->src_reg, insn->imm);		} else if (BPF_MODE(insn->code) == BPF_IMM &&			   BPF_SIZE(insn->code) == BPF_DW) {			/* At this point, we already made sure that the second			 * part of the ldimm64 insn is accessible.			 */			u64 imm = ((u64)(insn + 1)->imm << 32) | (u32)insn->imm;			bool is_ptr = insn->src_reg == BPF_PSEUDO_MAP_FD ||				      insn->src_reg == BPF_PSEUDO_MAP_VALUE;			char tmp[64]; 			if (is_ptr && !allow_ptr_leaks)				imm = 0; 			verbose(cbs->private_data, "(%02x) r%d = %s\n",				insn->code, insn->dst_reg,				__func_imm_name(cbs, insn, imm,						tmp, sizeof(tmp)));		} else {			verbose(cbs->private_data, "BUG_ld_%02x\n", insn->code);			return;		}	} else if (class == BPF_JMP32 || class == BPF_JMP) {		u8 opcode = BPF_OP(insn->code); 		if (opcode == BPF_CALL) {			char tmp[64]; 			if (insn->src_reg == BPF_PSEUDO_CALL) {				verbose(cbs->private_data, "(%02x) call pc%s\n",					insn->code,					__func_get_name(cbs, insn,							tmp, sizeof(tmp)));			} else {				strcpy(tmp, "unknown");				verbose(cbs->private_data, "(%02x) call %s#%d\n", insn->code,					__func_get_name(cbs, insn,							tmp, sizeof(tmp)),					insn->imm);			}		} else if (insn->code == (BPF_JMP | BPF_JA)) {			verbose(cbs->private_data, "(%02x) goto pc%+d\n",				insn->code, insn->off);		} else if (insn->code == (BPF_JMP | BPF_EXIT)) {			verbose(cbs->private_data, "(%02x) exit\n", insn->code);		} else if (BPF_SRC(insn->code) == BPF_X) {			verbose(cbs->private_data,				"(%02x) if %c%d %s %c%d goto pc%+d\n",				insn->code, class == BPF_JMP32 ? 'w' : 'r',				insn->dst_reg,				bpf_jmp_string[BPF_OP(insn->code) >> 4],				class == BPF_JMP32 ? 'w' : 'r',				insn->src_reg, insn->off);		} else {			verbose(cbs->private_data,				"(%02x) if %c%d %s 0x%x goto pc%+d\n",				insn->code, class == BPF_JMP32 ? 'w' : 'r',				insn->dst_reg,				bpf_jmp_string[BPF_OP(insn->code) >> 4],				insn->imm, insn->off);		}	} else {		verbose(cbs->private_data, "(%02x) %s\n",			insn->code, bpf_class_string[class]);	}}