/* * 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> #include <linux/module.h> const char hex_asc[] = "0123456789abcdef"; EXPORT_SYMBOL(hex_asc); /** * 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 * @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) * @linebuf: where to put the converted data * @linebuflen: total size of @linebuf, including space for terminating NUL * @ascii: include ASCII after the hex output * * hex_dump_to_buffer() works on one "line" of output at a time, i.e., * 16 or 32 bytes of input data converted to hex + ASCII output. * * 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.: * hex_dump_to_buffer(frame->data, frame->len, 16, 1, * linebuf, sizeof(linebuf), 1); * * example output buffer: * 40 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e 4f @ABCDEFGHIJKLMNO */ void hex_dump_to_buffer(const void *buf, size_t len, int rowsize, int groupsize, char *linebuf, size_t linebuflen, bool ascii) { const u8 *ptr = buf; u8 ch; int j, lx = 0; int ascii_column; if (rowsize != 16 && rowsize != 32) rowsize = 16; if (!len) goto nil; if (len > rowsize) /* limit to one line at a time */ len = rowsize; if ((len % groupsize) != 0) /* no mixed size output */ groupsize = 1; switch (groupsize) { case 8: { const u64 *ptr8 = buf; int ngroups = len / groupsize; for (j = 0; j < ngroups; j++) lx += scnprintf(linebuf + lx, linebuflen - lx, "%16.16llx ", (unsigned long long)*(ptr8 + j)); ascii_column = 17 * ngroups + 2; break; } case 4: { const u32 *ptr4 = buf; int ngroups = len / groupsize; for (j = 0; j < ngroups; j++) lx += scnprintf(linebuf + lx, linebuflen - lx, "%8.8x ", *(ptr4 + j)); ascii_column = 9 * ngroups + 2; break; } case 2: { const u16 *ptr2 = buf; int ngroups = len / groupsize; for (j = 0; j < ngroups; j++) lx += scnprintf(linebuf + lx, linebuflen - lx, "%4.4x ", *(ptr2 + j)); ascii_column = 5 * ngroups + 2; break; } default: for (j = 0; (j < rowsize) && (j < len) && (lx + 4) < linebuflen; j++) { ch = ptr[j]; linebuf[lx++] = hex_asc_hi(ch); linebuf[lx++] = hex_asc_lo(ch); linebuf[lx++] = ' '; } ascii_column = 3 * rowsize + 2; break; } if (!ascii) goto nil; while (lx < (linebuflen - 1) && lx < (ascii_column - 1)) linebuf[lx++] = ' '; for (j = 0; (j < rowsize) && (j < len) && (lx + 2) < linebuflen; j++) linebuf[lx++] = (isascii(ptr[j]) && isprint(ptr[j])) ? ptr[j] : '.'; nil: linebuf[lx++] = '\0'; } EXPORT_SYMBOL(hex_dump_to_buffer); /** * print_hex_dump - print a text hex dump to syslog for a binary blob of data * @level: kernel log level (e.g. KERN_DEBUG) * @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) * @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) * @buf: data blob to dump * @len: number of bytes in the @buf * @ascii: include ASCII after the hex output * * 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. * * 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. * * E.g.: * print_hex_dump(KERN_DEBUG, "raw data: ", DUMP_PREFIX_ADDRESS, * 16, 1, frame->data, frame->len, 1); * * 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{|}~. */ void print_hex_dump(const char *level, const char *prefix_str, int prefix_type, int rowsize, int groupsize, const void *buf, size_t len, bool ascii) { const u8 *ptr = buf; int i, linelen, remaining = len; unsigned char linebuf[200]; if (rowsize != 16 && rowsize != 32) rowsize = 16; for (i = 0; i < len; i += rowsize) { linelen = min(remaining, rowsize); remaining -= rowsize; hex_dump_to_buffer(ptr + i, linelen, rowsize, groupsize, linebuf, sizeof(linebuf), ascii); switch (prefix_type) { case DUMP_PREFIX_ADDRESS: printk("%s%s%*p: %s\n", level, prefix_str, (int)(2 * sizeof(void *)), ptr + i, linebuf); break; case DUMP_PREFIX_OFFSET: printk("%s%s%.8x: %s\n", level, prefix_str, i, linebuf); break; default: printk("%s%s%s\n", level, prefix_str, linebuf); break; } } } EXPORT_SYMBOL(print_hex_dump); /** * 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, const void *buf, size_t len) { print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, 16, 1, buf, len, 1); } EXPORT_SYMBOL(print_hex_dump_bytes);