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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * lib/hexdump.c
4 */
5
6#include <linux/types.h>
7#include <linux/ctype.h>
8#include <linux/errno.h>
9#include <linux/kernel.h>
10#include <linux/minmax.h>
11#include <linux/export.h>
12#include <asm/unaligned.h>
13
14const char hex_asc[] = "0123456789abcdef";
15EXPORT_SYMBOL(hex_asc);
16const char hex_asc_upper[] = "0123456789ABCDEF";
17EXPORT_SYMBOL(hex_asc_upper);
18
19/**
20 * hex_to_bin - convert a hex digit to its real value
21 * @ch: ascii character represents hex digit
22 *
23 * hex_to_bin() converts one hex digit to its actual value or -1 in case of bad
24 * input.
25 */
26int hex_to_bin(char ch)
27{
28 if ((ch >= '0') && (ch <= '9'))
29 return ch - '0';
30 ch = tolower(ch);
31 if ((ch >= 'a') && (ch <= 'f'))
32 return ch - 'a' + 10;
33 return -1;
34}
35EXPORT_SYMBOL(hex_to_bin);
36
37/**
38 * hex2bin - convert an ascii hexadecimal string to its binary representation
39 * @dst: binary result
40 * @src: ascii hexadecimal string
41 * @count: result length
42 *
43 * Return 0 on success, -EINVAL in case of bad input.
44 */
45int hex2bin(u8 *dst, const char *src, size_t count)
46{
47 while (count--) {
48 int hi = hex_to_bin(*src++);
49 int lo = hex_to_bin(*src++);
50
51 if ((hi < 0) || (lo < 0))
52 return -EINVAL;
53
54 *dst++ = (hi << 4) | lo;
55 }
56 return 0;
57}
58EXPORT_SYMBOL(hex2bin);
59
60/**
61 * bin2hex - convert binary data to an ascii hexadecimal string
62 * @dst: ascii hexadecimal result
63 * @src: binary data
64 * @count: binary data length
65 */
66char *bin2hex(char *dst, const void *src, size_t count)
67{
68 const unsigned char *_src = src;
69
70 while (count--)
71 dst = hex_byte_pack(dst, *_src++);
72 return dst;
73}
74EXPORT_SYMBOL(bin2hex);
75
76/**
77 * hex_dump_to_buffer - convert a blob of data to "hex ASCII" in memory
78 * @buf: data blob to dump
79 * @len: number of bytes in the @buf
80 * @rowsize: number of bytes to print per line; must be 16 or 32
81 * @groupsize: number of bytes to print at a time (1, 2, 4, 8; default = 1)
82 * @linebuf: where to put the converted data
83 * @linebuflen: total size of @linebuf, including space for terminating NUL
84 * @ascii: include ASCII after the hex output
85 *
86 * hex_dump_to_buffer() works on one "line" of output at a time, i.e.,
87 * 16 or 32 bytes of input data converted to hex + ASCII output.
88 *
89 * Given a buffer of u8 data, hex_dump_to_buffer() converts the input data
90 * to a hex + ASCII dump at the supplied memory location.
91 * The converted output is always NUL-terminated.
92 *
93 * E.g.:
94 * hex_dump_to_buffer(frame->data, frame->len, 16, 1,
95 * linebuf, sizeof(linebuf), true);
96 *
97 * example output buffer:
98 * 40 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e 4f @ABCDEFGHIJKLMNO
99 *
100 * Return:
101 * The amount of bytes placed in the buffer without terminating NUL. If the
102 * output was truncated, then the return value is the number of bytes
103 * (excluding the terminating NUL) which would have been written to the final
104 * string if enough space had been available.
105 */
106int hex_dump_to_buffer(const void *buf, size_t len, int rowsize, int groupsize,
107 char *linebuf, size_t linebuflen, bool ascii)
108{
109 const u8 *ptr = buf;
110 int ngroups;
111 u8 ch;
112 int j, lx = 0;
113 int ascii_column;
114 int ret;
115
116 if (rowsize != 16 && rowsize != 32)
117 rowsize = 16;
118
119 if (len > rowsize) /* limit to one line at a time */
120 len = rowsize;
121 if (!is_power_of_2(groupsize) || groupsize > 8)
122 groupsize = 1;
123 if ((len % groupsize) != 0) /* no mixed size output */
124 groupsize = 1;
125
126 ngroups = len / groupsize;
127 ascii_column = rowsize * 2 + rowsize / groupsize + 1;
128
129 if (!linebuflen)
130 goto overflow1;
131
132 if (!len)
133 goto nil;
134
135 if (groupsize == 8) {
136 const u64 *ptr8 = buf;
137
138 for (j = 0; j < ngroups; j++) {
139 ret = snprintf(linebuf + lx, linebuflen - lx,
140 "%s%16.16llx", j ? " " : "",
141 get_unaligned(ptr8 + j));
142 if (ret >= linebuflen - lx)
143 goto overflow1;
144 lx += ret;
145 }
146 } else if (groupsize == 4) {
147 const u32 *ptr4 = buf;
148
149 for (j = 0; j < ngroups; j++) {
150 ret = snprintf(linebuf + lx, linebuflen - lx,
151 "%s%8.8x", j ? " " : "",
152 get_unaligned(ptr4 + j));
153 if (ret >= linebuflen - lx)
154 goto overflow1;
155 lx += ret;
156 }
157 } else if (groupsize == 2) {
158 const u16 *ptr2 = buf;
159
160 for (j = 0; j < ngroups; j++) {
161 ret = snprintf(linebuf + lx, linebuflen - lx,
162 "%s%4.4x", j ? " " : "",
163 get_unaligned(ptr2 + j));
164 if (ret >= linebuflen - lx)
165 goto overflow1;
166 lx += ret;
167 }
168 } else {
169 for (j = 0; j < len; j++) {
170 if (linebuflen < lx + 2)
171 goto overflow2;
172 ch = ptr[j];
173 linebuf[lx++] = hex_asc_hi(ch);
174 if (linebuflen < lx + 2)
175 goto overflow2;
176 linebuf[lx++] = hex_asc_lo(ch);
177 if (linebuflen < lx + 2)
178 goto overflow2;
179 linebuf[lx++] = ' ';
180 }
181 if (j)
182 lx--;
183 }
184 if (!ascii)
185 goto nil;
186
187 while (lx < ascii_column) {
188 if (linebuflen < lx + 2)
189 goto overflow2;
190 linebuf[lx++] = ' ';
191 }
192 for (j = 0; j < len; j++) {
193 if (linebuflen < lx + 2)
194 goto overflow2;
195 ch = ptr[j];
196 linebuf[lx++] = (isascii(ch) && isprint(ch)) ? ch : '.';
197 }
198nil:
199 linebuf[lx] = '\0';
200 return lx;
201overflow2:
202 linebuf[lx++] = '\0';
203overflow1:
204 return ascii ? ascii_column + len : (groupsize * 2 + 1) * ngroups - 1;
205}
206EXPORT_SYMBOL(hex_dump_to_buffer);
207
208#ifdef CONFIG_PRINTK
209/**
210 * print_hex_dump - print a text hex dump to syslog for a binary blob of data
211 * @level: kernel log level (e.g. KERN_DEBUG)
212 * @prefix_str: string to prefix each line with;
213 * caller supplies trailing spaces for alignment if desired
214 * @prefix_type: controls whether prefix of an offset, address, or none
215 * is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE)
216 * @rowsize: number of bytes to print per line; must be 16 or 32
217 * @groupsize: number of bytes to print at a time (1, 2, 4, 8; default = 1)
218 * @buf: data blob to dump
219 * @len: number of bytes in the @buf
220 * @ascii: include ASCII after the hex output
221 *
222 * Given a buffer of u8 data, print_hex_dump() prints a hex + ASCII dump
223 * to the kernel log at the specified kernel log level, with an optional
224 * leading prefix.
225 *
226 * print_hex_dump() works on one "line" of output at a time, i.e.,
227 * 16 or 32 bytes of input data converted to hex + ASCII output.
228 * print_hex_dump() iterates over the entire input @buf, breaking it into
229 * "line size" chunks to format and print.
230 *
231 * E.g.:
232 * print_hex_dump(KERN_DEBUG, "raw data: ", DUMP_PREFIX_ADDRESS,
233 * 16, 1, frame->data, frame->len, true);
234 *
235 * Example output using %DUMP_PREFIX_OFFSET and 1-byte mode:
236 * 0009ab42: 40 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e 4f @ABCDEFGHIJKLMNO
237 * Example output using %DUMP_PREFIX_ADDRESS and 4-byte mode:
238 * ffffffff88089af0: 73727170 77767574 7b7a7978 7f7e7d7c pqrstuvwxyz{|}~.
239 */
240void print_hex_dump(const char *level, const char *prefix_str, int prefix_type,
241 int rowsize, int groupsize,
242 const void *buf, size_t len, bool ascii)
243{
244 const u8 *ptr = buf;
245 int i, linelen, remaining = len;
246 unsigned char linebuf[32 * 3 + 2 + 32 + 1];
247
248 if (rowsize != 16 && rowsize != 32)
249 rowsize = 16;
250
251 for (i = 0; i < len; i += rowsize) {
252 linelen = min(remaining, rowsize);
253 remaining -= rowsize;
254
255 hex_dump_to_buffer(ptr + i, linelen, rowsize, groupsize,
256 linebuf, sizeof(linebuf), ascii);
257
258 switch (prefix_type) {
259 case DUMP_PREFIX_ADDRESS:
260 printk("%s%s%p: %s\n",
261 level, prefix_str, ptr + i, linebuf);
262 break;
263 case DUMP_PREFIX_OFFSET:
264 printk("%s%s%.8x: %s\n", level, prefix_str, i, linebuf);
265 break;
266 default:
267 printk("%s%s%s\n", level, prefix_str, linebuf);
268 break;
269 }
270 }
271}
272EXPORT_SYMBOL(print_hex_dump);
273
274#endif /* defined(CONFIG_PRINTK) */
1/*
2 * lib/hexdump.c
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation. See README and COPYING for
7 * more details.
8 */
9
10#include <linux/types.h>
11#include <linux/ctype.h>
12#include <linux/kernel.h>
13#include <linux/export.h>
14
15const char hex_asc[] = "0123456789abcdef";
16EXPORT_SYMBOL(hex_asc);
17
18/**
19 * hex_to_bin - convert a hex digit to its real value
20 * @ch: ascii character represents hex digit
21 *
22 * hex_to_bin() converts one hex digit to its actual value or -1 in case of bad
23 * input.
24 */
25int hex_to_bin(char ch)
26{
27 if ((ch >= '0') && (ch <= '9'))
28 return ch - '0';
29 ch = tolower(ch);
30 if ((ch >= 'a') && (ch <= 'f'))
31 return ch - 'a' + 10;
32 return -1;
33}
34EXPORT_SYMBOL(hex_to_bin);
35
36/**
37 * hex2bin - convert an ascii hexadecimal string to its binary representation
38 * @dst: binary result
39 * @src: ascii hexadecimal string
40 * @count: result length
41 *
42 * Return 0 on success, -1 in case of bad input.
43 */
44int hex2bin(u8 *dst, const char *src, size_t count)
45{
46 while (count--) {
47 int hi = hex_to_bin(*src++);
48 int lo = hex_to_bin(*src++);
49
50 if ((hi < 0) || (lo < 0))
51 return -1;
52
53 *dst++ = (hi << 4) | lo;
54 }
55 return 0;
56}
57EXPORT_SYMBOL(hex2bin);
58
59/**
60 * hex_dump_to_buffer - convert a blob of data to "hex ASCII" in memory
61 * @buf: data blob to dump
62 * @len: number of bytes in the @buf
63 * @rowsize: number of bytes to print per line; must be 16 or 32
64 * @groupsize: number of bytes to print at a time (1, 2, 4, 8; default = 1)
65 * @linebuf: where to put the converted data
66 * @linebuflen: total size of @linebuf, including space for terminating NUL
67 * @ascii: include ASCII after the hex output
68 *
69 * hex_dump_to_buffer() works on one "line" of output at a time, i.e.,
70 * 16 or 32 bytes of input data converted to hex + ASCII output.
71 *
72 * Given a buffer of u8 data, hex_dump_to_buffer() converts the input data
73 * to a hex + ASCII dump at the supplied memory location.
74 * The converted output is always NUL-terminated.
75 *
76 * E.g.:
77 * hex_dump_to_buffer(frame->data, frame->len, 16, 1,
78 * linebuf, sizeof(linebuf), true);
79 *
80 * example output buffer:
81 * 40 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e 4f @ABCDEFGHIJKLMNO
82 */
83void hex_dump_to_buffer(const void *buf, size_t len, int rowsize,
84 int groupsize, char *linebuf, size_t linebuflen,
85 bool ascii)
86{
87 const u8 *ptr = buf;
88 u8 ch;
89 int j, lx = 0;
90 int ascii_column;
91
92 if (rowsize != 16 && rowsize != 32)
93 rowsize = 16;
94
95 if (!len)
96 goto nil;
97 if (len > rowsize) /* limit to one line at a time */
98 len = rowsize;
99 if ((len % groupsize) != 0) /* no mixed size output */
100 groupsize = 1;
101
102 switch (groupsize) {
103 case 8: {
104 const u64 *ptr8 = buf;
105 int ngroups = len / groupsize;
106
107 for (j = 0; j < ngroups; j++)
108 lx += scnprintf(linebuf + lx, linebuflen - lx,
109 "%s%16.16llx", j ? " " : "",
110 (unsigned long long)*(ptr8 + j));
111 ascii_column = 17 * ngroups + 2;
112 break;
113 }
114
115 case 4: {
116 const u32 *ptr4 = buf;
117 int ngroups = len / groupsize;
118
119 for (j = 0; j < ngroups; j++)
120 lx += scnprintf(linebuf + lx, linebuflen - lx,
121 "%s%8.8x", j ? " " : "", *(ptr4 + j));
122 ascii_column = 9 * ngroups + 2;
123 break;
124 }
125
126 case 2: {
127 const u16 *ptr2 = buf;
128 int ngroups = len / groupsize;
129
130 for (j = 0; j < ngroups; j++)
131 lx += scnprintf(linebuf + lx, linebuflen - lx,
132 "%s%4.4x", j ? " " : "", *(ptr2 + j));
133 ascii_column = 5 * ngroups + 2;
134 break;
135 }
136
137 default:
138 for (j = 0; (j < len) && (lx + 3) <= linebuflen; j++) {
139 ch = ptr[j];
140 linebuf[lx++] = hex_asc_hi(ch);
141 linebuf[lx++] = hex_asc_lo(ch);
142 linebuf[lx++] = ' ';
143 }
144 if (j)
145 lx--;
146
147 ascii_column = 3 * rowsize + 2;
148 break;
149 }
150 if (!ascii)
151 goto nil;
152
153 while (lx < (linebuflen - 1) && lx < (ascii_column - 1))
154 linebuf[lx++] = ' ';
155 for (j = 0; (j < len) && (lx + 2) < linebuflen; j++) {
156 ch = ptr[j];
157 linebuf[lx++] = (isascii(ch) && isprint(ch)) ? ch : '.';
158 }
159nil:
160 linebuf[lx++] = '\0';
161}
162EXPORT_SYMBOL(hex_dump_to_buffer);
163
164#ifdef CONFIG_PRINTK
165/**
166 * print_hex_dump - print a text hex dump to syslog for a binary blob of data
167 * @level: kernel log level (e.g. KERN_DEBUG)
168 * @prefix_str: string to prefix each line with;
169 * caller supplies trailing spaces for alignment if desired
170 * @prefix_type: controls whether prefix of an offset, address, or none
171 * is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE)
172 * @rowsize: number of bytes to print per line; must be 16 or 32
173 * @groupsize: number of bytes to print at a time (1, 2, 4, 8; default = 1)
174 * @buf: data blob to dump
175 * @len: number of bytes in the @buf
176 * @ascii: include ASCII after the hex output
177 *
178 * Given a buffer of u8 data, print_hex_dump() prints a hex + ASCII dump
179 * to the kernel log at the specified kernel log level, with an optional
180 * leading prefix.
181 *
182 * print_hex_dump() works on one "line" of output at a time, i.e.,
183 * 16 or 32 bytes of input data converted to hex + ASCII output.
184 * print_hex_dump() iterates over the entire input @buf, breaking it into
185 * "line size" chunks to format and print.
186 *
187 * E.g.:
188 * print_hex_dump(KERN_DEBUG, "raw data: ", DUMP_PREFIX_ADDRESS,
189 * 16, 1, frame->data, frame->len, true);
190 *
191 * Example output using %DUMP_PREFIX_OFFSET and 1-byte mode:
192 * 0009ab42: 40 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e 4f @ABCDEFGHIJKLMNO
193 * Example output using %DUMP_PREFIX_ADDRESS and 4-byte mode:
194 * ffffffff88089af0: 73727170 77767574 7b7a7978 7f7e7d7c pqrstuvwxyz{|}~.
195 */
196void print_hex_dump(const char *level, const char *prefix_str, int prefix_type,
197 int rowsize, int groupsize,
198 const void *buf, size_t len, bool ascii)
199{
200 const u8 *ptr = buf;
201 int i, linelen, remaining = len;
202 unsigned char linebuf[32 * 3 + 2 + 32 + 1];
203
204 if (rowsize != 16 && rowsize != 32)
205 rowsize = 16;
206
207 for (i = 0; i < len; i += rowsize) {
208 linelen = min(remaining, rowsize);
209 remaining -= rowsize;
210
211 hex_dump_to_buffer(ptr + i, linelen, rowsize, groupsize,
212 linebuf, sizeof(linebuf), ascii);
213
214 switch (prefix_type) {
215 case DUMP_PREFIX_ADDRESS:
216 printk("%s%s%p: %s\n",
217 level, prefix_str, ptr + i, linebuf);
218 break;
219 case DUMP_PREFIX_OFFSET:
220 printk("%s%s%.8x: %s\n", level, prefix_str, i, linebuf);
221 break;
222 default:
223 printk("%s%s%s\n", level, prefix_str, linebuf);
224 break;
225 }
226 }
227}
228EXPORT_SYMBOL(print_hex_dump);
229
230/**
231 * print_hex_dump_bytes - shorthand form of print_hex_dump() with default params
232 * @prefix_str: string to prefix each line with;
233 * caller supplies trailing spaces for alignment if desired
234 * @prefix_type: controls whether prefix of an offset, address, or none
235 * is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE)
236 * @buf: data blob to dump
237 * @len: number of bytes in the @buf
238 *
239 * Calls print_hex_dump(), with log level of KERN_DEBUG,
240 * rowsize of 16, groupsize of 1, and ASCII output included.
241 */
242void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
243 const void *buf, size_t len)
244{
245 print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, 16, 1,
246 buf, len, true);
247}
248EXPORT_SYMBOL(print_hex_dump_bytes);
249#endif