diff options
Diffstat (limited to 'arch/x86/tools/insn_sanity.c')
| -rw-r--r-- | arch/x86/tools/insn_sanity.c | 281 | 
1 files changed, 281 insertions, 0 deletions
diff --git a/arch/x86/tools/insn_sanity.c b/arch/x86/tools/insn_sanity.c new file mode 100644 index 00000000000..872eb60e780 --- /dev/null +++ b/arch/x86/tools/insn_sanity.c @@ -0,0 +1,281 @@ +/* + * x86 decoder sanity test - based on test_get_insn.c + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * Copyright (C) IBM Corporation, 2009 + * Copyright (C) Hitachi, Ltd., 2011 + */ + +#include <stdlib.h> +#include <stdio.h> +#include <string.h> +#include <assert.h> +#include <unistd.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> + +#define unlikely(cond) (cond) +#define ARRAY_SIZE(a)	(sizeof(a)/sizeof(a[0])) + +#include <asm/insn.h> +#include <inat.c> +#include <insn.c> + +/* + * Test of instruction analysis against tampering. + * Feed random binary to instruction decoder and ensure not to + * access out-of-instruction-buffer. + */ + +#define DEFAULT_MAX_ITER	10000 +#define INSN_NOP 0x90 + +static const char	*prog;		/* Program name */ +static int		verbose;	/* Verbosity */ +static int		x86_64;		/* x86-64 bit mode flag */ +static unsigned int	seed;		/* Random seed */ +static unsigned long	iter_start;	/* Start of iteration number */ +static unsigned long	iter_end = DEFAULT_MAX_ITER;	/* End of iteration number */ +static FILE		*input_file;	/* Input file name */ + +static void usage(const char *err) +{ +	if (err) +		fprintf(stderr, "%s: Error: %s\n\n", prog, err); +	fprintf(stderr, "Usage: %s [-y|-n|-v] [-s seed[,no]] [-m max] [-i input]\n", prog); +	fprintf(stderr, "\t-y	64bit mode\n"); +	fprintf(stderr, "\t-n	32bit mode\n"); +	fprintf(stderr, "\t-v	Verbosity(-vv dumps any decoded result)\n"); +	fprintf(stderr, "\t-s	Give a random seed (and iteration number)\n"); +	fprintf(stderr, "\t-m	Give a maximum iteration number\n"); +	fprintf(stderr, "\t-i	Give an input file with decoded binary\n"); +	exit(1); +} + +static void dump_field(FILE *fp, const char *name, const char *indent, +		       struct insn_field *field) +{ +	fprintf(fp, "%s.%s = {\n", indent, name); +	fprintf(fp, "%s\t.value = %d, bytes[] = {%x, %x, %x, %x},\n", +		indent, field->value, field->bytes[0], field->bytes[1], +		field->bytes[2], field->bytes[3]); +	fprintf(fp, "%s\t.got = %d, .nbytes = %d},\n", indent, +		field->got, field->nbytes); +} + +static void dump_insn(FILE *fp, struct insn *insn) +{ +	fprintf(fp, "Instruction = {\n"); +	dump_field(fp, "prefixes", "\t",	&insn->prefixes); +	dump_field(fp, "rex_prefix", "\t",	&insn->rex_prefix); +	dump_field(fp, "vex_prefix", "\t",	&insn->vex_prefix); +	dump_field(fp, "opcode", "\t",		&insn->opcode); +	dump_field(fp, "modrm", "\t",		&insn->modrm); +	dump_field(fp, "sib", "\t",		&insn->sib); +	dump_field(fp, "displacement", "\t",	&insn->displacement); +	dump_field(fp, "immediate1", "\t",	&insn->immediate1); +	dump_field(fp, "immediate2", "\t",	&insn->immediate2); +	fprintf(fp, "\t.attr = %x, .opnd_bytes = %d, .addr_bytes = %d,\n", +		insn->attr, insn->opnd_bytes, insn->addr_bytes); +	fprintf(fp, "\t.length = %d, .x86_64 = %d, .kaddr = %p}\n", +		insn->length, insn->x86_64, insn->kaddr); +} + +static void dump_stream(FILE *fp, const char *msg, unsigned long nr_iter, +			unsigned char *insn_buf, struct insn *insn) +{ +	int i; + +	fprintf(fp, "%s:\n", msg); + +	dump_insn(fp, insn); + +	fprintf(fp, "You can reproduce this with below command(s);\n"); + +	/* Input a decoded instruction sequence directly */ +	fprintf(fp, " $ echo "); +	for (i = 0; i < MAX_INSN_SIZE; i++) +		fprintf(fp, " %02x", insn_buf[i]); +	fprintf(fp, " | %s -i -\n", prog); + +	if (!input_file) { +		fprintf(fp, "Or \n"); +		/* Give a seed and iteration number */ +		fprintf(fp, " $ %s -s 0x%x,%lu\n", prog, seed, nr_iter); +	} +} + +static void init_random_seed(void) +{ +	int fd; + +	fd = open("/dev/urandom", O_RDONLY); +	if (fd < 0) +		goto fail; + +	if (read(fd, &seed, sizeof(seed)) != sizeof(seed)) +		goto fail; + +	close(fd); +	return; +fail: +	usage("Failed to open /dev/urandom"); +} + +/* Read given instruction sequence from the input file */ +static int read_next_insn(unsigned char *insn_buf) +{ +	char buf[256]  = "", *tmp; +	int i; + +	tmp = fgets(buf, ARRAY_SIZE(buf), input_file); +	if (tmp == NULL || feof(input_file)) +		return 0; + +	for (i = 0; i < MAX_INSN_SIZE; i++) { +		insn_buf[i] = (unsigned char)strtoul(tmp, &tmp, 16); +		if (*tmp != ' ') +			break; +	} + +	return i; +} + +static int generate_insn(unsigned char *insn_buf) +{ +	int i; + +	if (input_file) +		return read_next_insn(insn_buf); + +	/* Fills buffer with random binary up to MAX_INSN_SIZE */ +	for (i = 0; i < MAX_INSN_SIZE - 1; i += 2) +		*(unsigned short *)(&insn_buf[i]) = random() & 0xffff; + +	while (i < MAX_INSN_SIZE) +		insn_buf[i++] = random() & 0xff; + +	return i; +} + +static void parse_args(int argc, char **argv) +{ +	int c; +	char *tmp = NULL; +	int set_seed = 0; + +	prog = argv[0]; +	while ((c = getopt(argc, argv, "ynvs:m:i:")) != -1) { +		switch (c) { +		case 'y': +			x86_64 = 1; +			break; +		case 'n': +			x86_64 = 0; +			break; +		case 'v': +			verbose++; +			break; +		case 'i': +			if (strcmp("-", optarg) == 0) +				input_file = stdin; +			else +				input_file = fopen(optarg, "r"); +			if (!input_file) +				usage("Failed to open input file"); +			break; +		case 's': +			seed = (unsigned int)strtoul(optarg, &tmp, 0); +			if (*tmp == ',') { +				optarg = tmp + 1; +				iter_start = strtoul(optarg, &tmp, 0); +			} +			if (*tmp != '\0' || tmp == optarg) +				usage("Failed to parse seed"); +			set_seed = 1; +			break; +		case 'm': +			iter_end = strtoul(optarg, &tmp, 0); +			if (*tmp != '\0' || tmp == optarg) +				usage("Failed to parse max_iter"); +			break; +		default: +			usage(NULL); +		} +	} + +	/* Check errors */ +	if (iter_end < iter_start) +		usage("Max iteration number must be bigger than iter-num"); + +	if (set_seed && input_file) +		usage("Don't use input file (-i) with random seed (-s)"); + +	/* Initialize random seed */ +	if (!input_file) { +		if (!set_seed)	/* No seed is given */ +			init_random_seed(); +		srand(seed); +	} +} + +int main(int argc, char **argv) +{ +	struct insn insn; +	int insns = 0; +	int errors = 0; +	unsigned long i; +	unsigned char insn_buf[MAX_INSN_SIZE * 2]; + +	parse_args(argc, argv); + +	/* Prepare stop bytes with NOPs */ +	memset(insn_buf + MAX_INSN_SIZE, INSN_NOP, MAX_INSN_SIZE); + +	for (i = 0; i < iter_end; i++) { +		if (generate_insn(insn_buf) <= 0) +			break; + +		if (i < iter_start)	/* Skip to given iteration number */ +			continue; + +		/* Decode an instruction */ +		insn_init(&insn, insn_buf, x86_64); +		insn_get_length(&insn); + +		if (insn.next_byte <= insn.kaddr || +		    insn.kaddr + MAX_INSN_SIZE < insn.next_byte) { +			/* Access out-of-range memory */ +			dump_stream(stderr, "Error: Found an access violation", i, insn_buf, &insn); +			errors++; +		} else if (verbose && !insn_complete(&insn)) +			dump_stream(stdout, "Info: Found an undecodable input", i, insn_buf, &insn); +		else if (verbose >= 2) +			dump_insn(stdout, &insn); +		insns++; +	} + +	fprintf(stdout, "%s: %s: decoded and checked %d %s instructions with %d errors (seed:0x%x)\n", +		prog, +		(errors) ? "Failure" : "Success", +		insns, +		(input_file) ? "given" : "random", +		errors, +		seed); + +	return errors ? 1 : 0; +}  | 
