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 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 */ 25 int 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 } 34 EXPORT_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 */ 44 int 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 } 57 EXPORT_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 */ 83 void 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 } 159 nil: 160 linebuf[lx++] = '\0'; 161 } 162 EXPORT_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 */ 196 void 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 } 228 EXPORT_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 */ 242 void 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 } 248 EXPORT_SYMBOL(print_hex_dump_bytes); 249 #endif 250