hexdump.c 7.41 KB
Newer Older
Randy Dunlap's avatar
Randy Dunlap committed
1 2 3 4 5 6 7 8 9 10 11 12
/*
 * lib/hexdump.c
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation. See README and COPYING for
 * more details.
 */

#include <linux/types.h>
#include <linux/ctype.h>
#include <linux/kernel.h>
13
#include <linux/export.h>
Randy Dunlap's avatar
Randy Dunlap committed
14

15 16
const char hex_asc[] = "0123456789abcdef";
EXPORT_SYMBOL(hex_asc);
17 18
const char hex_asc_upper[] = "0123456789ABCDEF";
EXPORT_SYMBOL(hex_asc_upper);
19

20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37
/**
 * hex_to_bin - convert a hex digit to its real value
 * @ch: ascii character represents hex digit
 *
 * hex_to_bin() converts one hex digit to its actual value or -1 in case of bad
 * input.
 */
int hex_to_bin(char ch)
{
	if ((ch >= '0') && (ch <= '9'))
		return ch - '0';
	ch = tolower(ch);
	if ((ch >= 'a') && (ch <= 'f'))
		return ch - 'a' + 10;
	return -1;
}
EXPORT_SYMBOL(hex_to_bin);

38 39 40 41 42
/**
 * hex2bin - convert an ascii hexadecimal string to its binary representation
 * @dst: binary result
 * @src: ascii hexadecimal string
 * @count: result length
43 44
 *
 * Return 0 on success, -1 in case of bad input.
45
 */
46
int hex2bin(u8 *dst, const char *src, size_t count)
47 48
{
	while (count--) {
49 50 51 52 53 54 55
		int hi = hex_to_bin(*src++);
		int lo = hex_to_bin(*src++);

		if ((hi < 0) || (lo < 0))
			return -1;

		*dst++ = (hi << 4) | lo;
56
	}
57
	return 0;
58 59 60
}
EXPORT_SYMBOL(hex2bin);

61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76
/**
 * bin2hex - convert binary data to an ascii hexadecimal string
 * @dst: ascii hexadecimal result
 * @src: binary data
 * @count: binary data length
 */
char *bin2hex(char *dst, const void *src, size_t count)
{
	const unsigned char *_src = src;

	while (count--)
		dst = hex_byte_pack(dst, *_src++);
	return dst;
}
EXPORT_SYMBOL(bin2hex);

Randy Dunlap's avatar
Randy Dunlap committed
77 78 79 80
/**
 * hex_dump_to_buffer - convert a blob of data to "hex ASCII" in memory
 * @buf: data blob to dump
 * @len: number of bytes in the @buf
Randy Dunlap's avatar
Randy Dunlap committed
81 82
 * @rowsize: number of bytes to print per line; must be 16 or 32
 * @groupsize: number of bytes to print at a time (1, 2, 4, 8; default = 1)
Randy Dunlap's avatar
Randy Dunlap committed
83 84
 * @linebuf: where to put the converted data
 * @linebuflen: total size of @linebuf, including space for terminating NUL
Randy Dunlap's avatar
Randy Dunlap committed
85
 * @ascii: include ASCII after the hex output
Randy Dunlap's avatar
Randy Dunlap committed
86 87
 *
 * hex_dump_to_buffer() works on one "line" of output at a time, i.e.,
Randy Dunlap's avatar
Randy Dunlap committed
88
 * 16 or 32 bytes of input data converted to hex + ASCII output.
Randy Dunlap's avatar
Randy Dunlap committed
89 90 91 92 93 94
 *
 * Given a buffer of u8 data, hex_dump_to_buffer() converts the input data
 * to a hex + ASCII dump at the supplied memory location.
 * The converted output is always NUL-terminated.
 *
 * E.g.:
Randy Dunlap's avatar
Randy Dunlap committed
95
 *   hex_dump_to_buffer(frame->data, frame->len, 16, 1,
96
 *			linebuf, sizeof(linebuf), true);
Randy Dunlap's avatar
Randy Dunlap committed
97 98
 *
 * example output buffer:
Randy Dunlap's avatar
Randy Dunlap committed
99
 * 40 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e 4f  @ABCDEFGHIJKLMNO
Randy Dunlap's avatar
Randy Dunlap committed
100
 */
Randy Dunlap's avatar
Randy Dunlap committed
101 102 103
void hex_dump_to_buffer(const void *buf, size_t len, int rowsize,
			int groupsize, char *linebuf, size_t linebuflen,
			bool ascii)
Randy Dunlap's avatar
Randy Dunlap committed
104 105
{
	const u8 *ptr = buf;
106
	int ngroups;
Randy Dunlap's avatar
Randy Dunlap committed
107 108
	u8 ch;
	int j, lx = 0;
Randy Dunlap's avatar
Randy Dunlap committed
109
	int ascii_column;
Randy Dunlap's avatar
Randy Dunlap committed
110

Randy Dunlap's avatar
Randy Dunlap committed
111 112 113 114 115 116 117
	if (rowsize != 16 && rowsize != 32)
		rowsize = 16;

	if (!len)
		goto nil;
	if (len > rowsize)		/* limit to one line at a time */
		len = rowsize;
118 119
	if (!is_power_of_2(groupsize) || groupsize > 8)
		groupsize = 1;
Randy Dunlap's avatar
Randy Dunlap committed
120 121 122
	if ((len % groupsize) != 0)	/* no mixed size output */
		groupsize = 1;

123 124 125
	ngroups = len / groupsize;
	ascii_column = rowsize * 2 + rowsize / groupsize + 1;
	if (groupsize == 8) {
Randy Dunlap's avatar
Randy Dunlap committed
126 127 128 129
		const u64 *ptr8 = buf;

		for (j = 0; j < ngroups; j++)
			lx += scnprintf(linebuf + lx, linebuflen - lx,
130 131
					"%s%16.16llx", j ? " " : "",
					(unsigned long long)*(ptr8 + j));
132
	} else if (groupsize == 4) {
Randy Dunlap's avatar
Randy Dunlap committed
133 134 135 136
		const u32 *ptr4 = buf;

		for (j = 0; j < ngroups; j++)
			lx += scnprintf(linebuf + lx, linebuflen - lx,
137
					"%s%8.8x", j ? " " : "", *(ptr4 + j));
138
	} else if (groupsize == 2) {
Randy Dunlap's avatar
Randy Dunlap committed
139 140 141 142
		const u16 *ptr2 = buf;

		for (j = 0; j < ngroups; j++)
			lx += scnprintf(linebuf + lx, linebuflen - lx,
143
					"%s%4.4x", j ? " " : "", *(ptr2 + j));
144
	} else {
Li Zefan's avatar
Li Zefan committed
145
		for (j = 0; (j < len) && (lx + 3) <= linebuflen; j++) {
Randy Dunlap's avatar
Randy Dunlap committed
146
			ch = ptr[j];
147 148
			linebuf[lx++] = hex_asc_hi(ch);
			linebuf[lx++] = hex_asc_lo(ch);
Randy Dunlap's avatar
Randy Dunlap committed
149
			linebuf[lx++] = ' ';
Randy Dunlap's avatar
Randy Dunlap committed
150
		}
Li Zefan's avatar
Li Zefan committed
151 152
		if (j)
			lx--;
Randy Dunlap's avatar
Randy Dunlap committed
153
	}
Randy Dunlap's avatar
Randy Dunlap committed
154 155 156
	if (!ascii)
		goto nil;

157
	while (lx < (linebuflen - 1) && lx < ascii_column)
Randy Dunlap's avatar
Randy Dunlap committed
158
		linebuf[lx++] = ' ';
159 160 161 162
	for (j = 0; (j < len) && (lx + 2) < linebuflen; j++) {
		ch = ptr[j];
		linebuf[lx++] = (isascii(ch) && isprint(ch)) ? ch : '.';
	}
Randy Dunlap's avatar
Randy Dunlap committed
163
nil:
Randy Dunlap's avatar
Randy Dunlap committed
164 165 166 167
	linebuf[lx++] = '\0';
}
EXPORT_SYMBOL(hex_dump_to_buffer);

168
#ifdef CONFIG_PRINTK
Randy Dunlap's avatar
Randy Dunlap committed
169 170 171
/**
 * print_hex_dump - print a text hex dump to syslog for a binary blob of data
 * @level: kernel log level (e.g. KERN_DEBUG)
Randy Dunlap's avatar
Randy Dunlap committed
172 173
 * @prefix_str: string to prefix each line with;
 *  caller supplies trailing spaces for alignment if desired
Randy Dunlap's avatar
Randy Dunlap committed
174 175
 * @prefix_type: controls whether prefix of an offset, address, or none
 *  is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE)
Randy Dunlap's avatar
Randy Dunlap committed
176 177
 * @rowsize: number of bytes to print per line; must be 16 or 32
 * @groupsize: number of bytes to print at a time (1, 2, 4, 8; default = 1)
Randy Dunlap's avatar
Randy Dunlap committed
178 179
 * @buf: data blob to dump
 * @len: number of bytes in the @buf
Randy Dunlap's avatar
Randy Dunlap committed
180
 * @ascii: include ASCII after the hex output
Randy Dunlap's avatar
Randy Dunlap committed
181 182 183 184 185
 *
 * Given a buffer of u8 data, print_hex_dump() prints a hex + ASCII dump
 * to the kernel log at the specified kernel log level, with an optional
 * leading prefix.
 *
Randy Dunlap's avatar
Randy Dunlap committed
186 187 188 189 190
 * print_hex_dump() works on one "line" of output at a time, i.e.,
 * 16 or 32 bytes of input data converted to hex + ASCII output.
 * print_hex_dump() iterates over the entire input @buf, breaking it into
 * "line size" chunks to format and print.
 *
Randy Dunlap's avatar
Randy Dunlap committed
191
 * E.g.:
Randy Dunlap's avatar
Randy Dunlap committed
192
 *   print_hex_dump(KERN_DEBUG, "raw data: ", DUMP_PREFIX_ADDRESS,
193
 *		    16, 1, frame->data, frame->len, true);
Randy Dunlap's avatar
Randy Dunlap committed
194
 *
Randy Dunlap's avatar
Randy Dunlap committed
195 196 197 198
 * Example output using %DUMP_PREFIX_OFFSET and 1-byte mode:
 * 0009ab42: 40 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e 4f  @ABCDEFGHIJKLMNO
 * Example output using %DUMP_PREFIX_ADDRESS and 4-byte mode:
 * ffffffff88089af0: 73727170 77767574 7b7a7978 7f7e7d7c  pqrstuvwxyz{|}~.
Randy Dunlap's avatar
Randy Dunlap committed
199
 */
Randy Dunlap's avatar
Randy Dunlap committed
200
void print_hex_dump(const char *level, const char *prefix_str, int prefix_type,
201 202
		    int rowsize, int groupsize,
		    const void *buf, size_t len, bool ascii)
Randy Dunlap's avatar
Randy Dunlap committed
203
{
Artem Bityutskiy's avatar
Artem Bityutskiy committed
204
	const u8 *ptr = buf;
Randy Dunlap's avatar
Randy Dunlap committed
205
	int i, linelen, remaining = len;
206
	unsigned char linebuf[32 * 3 + 2 + 32 + 1];
Randy Dunlap's avatar
Randy Dunlap committed
207

Randy Dunlap's avatar
Randy Dunlap committed
208 209 210 211 212 213
	if (rowsize != 16 && rowsize != 32)
		rowsize = 16;

	for (i = 0; i < len; i += rowsize) {
		linelen = min(remaining, rowsize);
		remaining -= rowsize;
214

Randy Dunlap's avatar
Randy Dunlap committed
215
		hex_dump_to_buffer(ptr + i, linelen, rowsize, groupsize,
216
				   linebuf, sizeof(linebuf), ascii);
Randy Dunlap's avatar
Randy Dunlap committed
217 218 219

		switch (prefix_type) {
		case DUMP_PREFIX_ADDRESS:
220 221
			printk("%s%s%p: %s\n",
			       level, prefix_str, ptr + i, linebuf);
Randy Dunlap's avatar
Randy Dunlap committed
222 223
			break;
		case DUMP_PREFIX_OFFSET:
Randy Dunlap's avatar
Randy Dunlap committed
224
			printk("%s%s%.8x: %s\n", level, prefix_str, i, linebuf);
Randy Dunlap's avatar
Randy Dunlap committed
225 226
			break;
		default:
Randy Dunlap's avatar
Randy Dunlap committed
227
			printk("%s%s%s\n", level, prefix_str, linebuf);
Randy Dunlap's avatar
Randy Dunlap committed
228 229 230 231 232
			break;
		}
	}
}
EXPORT_SYMBOL(print_hex_dump);
Randy Dunlap's avatar
Randy Dunlap committed
233

234
#if !defined(CONFIG_DYNAMIC_DEBUG)
Randy Dunlap's avatar
Randy Dunlap committed
235 236 237 238 239 240 241 242 243 244 245 246 247
/**
 * print_hex_dump_bytes - shorthand form of print_hex_dump() with default params
 * @prefix_str: string to prefix each line with;
 *  caller supplies trailing spaces for alignment if desired
 * @prefix_type: controls whether prefix of an offset, address, or none
 *  is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE)
 * @buf: data blob to dump
 * @len: number of bytes in the @buf
 *
 * Calls print_hex_dump(), with log level of KERN_DEBUG,
 * rowsize of 16, groupsize of 1, and ASCII output included.
 */
void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
248
			  const void *buf, size_t len)
Randy Dunlap's avatar
Randy Dunlap committed
249 250
{
	print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, 16, 1,
251
		       buf, len, true);
Randy Dunlap's avatar
Randy Dunlap committed
252 253
}
EXPORT_SYMBOL(print_hex_dump_bytes);
254 255
#endif /* !defined(CONFIG_DYNAMIC_DEBUG) */
#endif /* defined(CONFIG_PRINTK) */