/*
* 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,
"%s%16.16llx", j ? " " : "",
(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,
"%s%8.8x", j ? " " : "", *(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,
"%s%4.4x", j ? " " : "", *(ptr2 + j));
ascii_column = 5 * ngroups + 2;
break;
}
default:
for (j = 0; (j < len) && (lx + 3) <= linebuflen; j++) {
ch = ptr[j];
linebuf[lx++] = hex_asc_hi(ch);
linebuf[lx++] = hex_asc_lo(ch);
linebuf[lx++] = ' ';
}
if (j)
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 < 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);
