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 15 const char hex_asc[] = "0123456789abcdef"; 16 EXPORT_SYMBOL(hex_asc); 17 const char hex_asc_upper[] = "0123456789ABCDEF"; 18 EXPORT_SYMBOL(hex_asc_upper); 19 20 /** 21 * hex_to_bin - convert a hex digit to its real value 22 * @ch: ascii character represents hex digit 23 * 24 * hex_to_bin() converts one hex digit to its actual value or -1 in case of bad 25 * input. 26 */ 27 int hex_to_bin(char ch) 28 { 29 if ((ch >= '0') && (ch <= '9')) 30 return ch - '0'; 31 ch = tolower(ch); 32 if ((ch >= 'a') && (ch <= 'f')) 33 return ch - 'a' + 10; 34 return -1; 35 } 36 EXPORT_SYMBOL(hex_to_bin); 37 38 /** 39 * hex2bin - convert an ascii hexadecimal string to its binary representation 40 * @dst: binary result 41 * @src: ascii hexadecimal string 42 * @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 int hi = hex_to_bin(*src++); 50 int lo = hex_to_bin(*src++); 51 52 if ((hi < 0) || (lo < 0)) 53 return -1; 54 55 *dst++ = (hi << 4) | lo; 56 } 57 return 0; 58 } 59 EXPORT_SYMBOL(hex2bin); 60 61 /** 62 * bin2hex - convert binary data to an ascii hexadecimal string 63 * @dst: ascii hexadecimal result 64 * @src: binary data 65 * @count: binary data length 66 */ 67 char *bin2hex(char *dst, const void *src, size_t count) 68 { 69 const unsigned char *_src = src; 70 71 while (count--) 72 dst = hex_byte_pack(dst, *_src++); 73 return dst; 74 } 75 EXPORT_SYMBOL(bin2hex); 76 77 /** 78 * hex_dump_to_buffer - convert a blob of data to "hex ASCII" in memory 79 * @buf: data blob to dump 80 * @len: number of bytes in the @buf 81 * @rowsize: number of bytes to print per line; must be 16 or 32 82 * @groupsize: number of bytes to print at a time (1, 2, 4, 8; default = 1) 83 * @linebuf: where to put the converted data 84 * @linebuflen: total size of @linebuf, including space for terminating NUL 85 * @ascii: include ASCII after the hex output 86 * 87 * hex_dump_to_buffer() works on one "line" of output at a time, i.e., 88 * 16 or 32 bytes of input data converted to hex + ASCII output. 89 * 90 * Given a buffer of u8 data, hex_dump_to_buffer() converts the input data 91 * to a hex + ASCII dump at the supplied memory location. 92 * The converted output is always NUL-terminated. 93 * 94 * E.g.: 95 * hex_dump_to_buffer(frame->data, frame->len, 16, 1, 96 * linebuf, sizeof(linebuf), true); 97 * 98 * example output buffer: 99 * 40 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e 4f @ABCDEFGHIJKLMNO 100 */ 101 void hex_dump_to_buffer(const void *buf, size_t len, int rowsize, 102 int groupsize, char *linebuf, size_t linebuflen, 103 bool ascii) 104 { 105 const u8 *ptr = buf; 106 u8 ch; 107 int j, lx = 0; 108 int ascii_column; 109 110 if (rowsize != 16 && rowsize != 32) 111 rowsize = 16; 112 113 if (!len) 114 goto nil; 115 if (len > rowsize) /* limit to one line at a time */ 116 len = rowsize; 117 if ((len % groupsize) != 0) /* no mixed size output */ 118 groupsize = 1; 119 120 switch (groupsize) { 121 case 8: { 122 const u64 *ptr8 = buf; 123 int ngroups = len / groupsize; 124 125 for (j = 0; j < ngroups; j++) 126 lx += scnprintf(linebuf + lx, linebuflen - lx, 127 "%s%16.16llx", j ? " " : "", 128 (unsigned long long)*(ptr8 + j)); 129 ascii_column = 17 * ngroups + 2; 130 break; 131 } 132 133 case 4: { 134 const u32 *ptr4 = buf; 135 int ngroups = len / groupsize; 136 137 for (j = 0; j < ngroups; j++) 138 lx += scnprintf(linebuf + lx, linebuflen - lx, 139 "%s%8.8x", j ? " " : "", *(ptr4 + j)); 140 ascii_column = 9 * ngroups + 2; 141 break; 142 } 143 144 case 2: { 145 const u16 *ptr2 = buf; 146 int ngroups = len / groupsize; 147 148 for (j = 0; j < ngroups; j++) 149 lx += scnprintf(linebuf + lx, linebuflen - lx, 150 "%s%4.4x", j ? " " : "", *(ptr2 + j)); 151 ascii_column = 5 * ngroups + 2; 152 break; 153 } 154 155 default: 156 for (j = 0; (j < len) && (lx + 3) <= linebuflen; j++) { 157 ch = ptr[j]; 158 linebuf[lx++] = hex_asc_hi(ch); 159 linebuf[lx++] = hex_asc_lo(ch); 160 linebuf[lx++] = ' '; 161 } 162 if (j) 163 lx--; 164 165 ascii_column = 3 * rowsize + 2; 166 break; 167 } 168 if (!ascii) 169 goto nil; 170 171 while (lx < (linebuflen - 1) && lx < (ascii_column - 1)) 172 linebuf[lx++] = ' '; 173 for (j = 0; (j < len) && (lx + 2) < linebuflen; j++) { 174 ch = ptr[j]; 175 linebuf[lx++] = (isascii(ch) && isprint(ch)) ? ch : '.'; 176 } 177 nil: 178 linebuf[lx++] = '\0'; 179 } 180 EXPORT_SYMBOL(hex_dump_to_buffer); 181 182 #ifdef CONFIG_PRINTK 183 /** 184 * print_hex_dump - print a text hex dump to syslog for a binary blob of data 185 * @level: kernel log level (e.g. KERN_DEBUG) 186 * @prefix_str: string to prefix each line with; 187 * caller supplies trailing spaces for alignment if desired 188 * @prefix_type: controls whether prefix of an offset, address, or none 189 * is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE) 190 * @rowsize: number of bytes to print per line; must be 16 or 32 191 * @groupsize: number of bytes to print at a time (1, 2, 4, 8; default = 1) 192 * @buf: data blob to dump 193 * @len: number of bytes in the @buf 194 * @ascii: include ASCII after the hex output 195 * 196 * Given a buffer of u8 data, print_hex_dump() prints a hex + ASCII dump 197 * to the kernel log at the specified kernel log level, with an optional 198 * leading prefix. 199 * 200 * print_hex_dump() works on one "line" of output at a time, i.e., 201 * 16 or 32 bytes of input data converted to hex + ASCII output. 202 * print_hex_dump() iterates over the entire input @buf, breaking it into 203 * "line size" chunks to format and print. 204 * 205 * E.g.: 206 * print_hex_dump(KERN_DEBUG, "raw data: ", DUMP_PREFIX_ADDRESS, 207 * 16, 1, frame->data, frame->len, true); 208 * 209 * Example output using %DUMP_PREFIX_OFFSET and 1-byte mode: 210 * 0009ab42: 40 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e 4f @ABCDEFGHIJKLMNO 211 * Example output using %DUMP_PREFIX_ADDRESS and 4-byte mode: 212 * ffffffff88089af0: 73727170 77767574 7b7a7978 7f7e7d7c pqrstuvwxyz{|}~. 213 */ 214 void print_hex_dump(const char *level, const char *prefix_str, int prefix_type, 215 int rowsize, int groupsize, 216 const void *buf, size_t len, bool ascii) 217 { 218 const u8 *ptr = buf; 219 int i, linelen, remaining = len; 220 unsigned char linebuf[32 * 3 + 2 + 32 + 1]; 221 222 if (rowsize != 16 && rowsize != 32) 223 rowsize = 16; 224 225 for (i = 0; i < len; i += rowsize) { 226 linelen = min(remaining, rowsize); 227 remaining -= rowsize; 228 229 hex_dump_to_buffer(ptr + i, linelen, rowsize, groupsize, 230 linebuf, sizeof(linebuf), ascii); 231 232 switch (prefix_type) { 233 case DUMP_PREFIX_ADDRESS: 234 printk("%s%s%p: %s\n", 235 level, prefix_str, ptr + i, linebuf); 236 break; 237 case DUMP_PREFIX_OFFSET: 238 printk("%s%s%.8x: %s\n", level, prefix_str, i, linebuf); 239 break; 240 default: 241 printk("%s%s%s\n", level, prefix_str, linebuf); 242 break; 243 } 244 } 245 } 246 EXPORT_SYMBOL(print_hex_dump); 247 248 #if !defined(CONFIG_DYNAMIC_DEBUG) 249 /** 250 * print_hex_dump_bytes - shorthand form of print_hex_dump() with default params 251 * @prefix_str: string to prefix each line with; 252 * caller supplies trailing spaces for alignment if desired 253 * @prefix_type: controls whether prefix of an offset, address, or none 254 * is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE) 255 * @buf: data blob to dump 256 * @len: number of bytes in the @buf 257 * 258 * Calls print_hex_dump(), with log level of KERN_DEBUG, 259 * rowsize of 16, groupsize of 1, and ASCII output included. 260 */ 261 void print_hex_dump_bytes(const char *prefix_str, int prefix_type, 262 const void *buf, size_t len) 263 { 264 print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, 16, 1, 265 buf, len, true); 266 } 267 EXPORT_SYMBOL(print_hex_dump_bytes); 268 #endif /* !defined(CONFIG_DYNAMIC_DEBUG) */ 269 #endif /* defined(CONFIG_PRINTK) */ 270