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Diffstat (limited to 'lib/hexdump.c')
| -rw-r--r-- | lib/hexdump.c | 292 |
1 files changed, 292 insertions, 0 deletions
diff --git a/lib/hexdump.c b/lib/hexdump.c new file mode 100644 index 000000000..7ea096998 --- /dev/null +++ b/lib/hexdump.c @@ -0,0 +1,292 @@ +/* + * 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/export.h> + +const char hex_asc[] = "0123456789abcdef"; +EXPORT_SYMBOL(hex_asc); +const char hex_asc_upper[] = "0123456789ABCDEF"; +EXPORT_SYMBOL(hex_asc_upper); + +/** + * hex_to_bin - convert a hex digit to its real value + * @ch: ascii character represents hex digit + * + * hex_to_bin() converts one hex digit to its actual value or -1 in case of bad + * input. + */ +int hex_to_bin(char ch) +{ + if ((ch >= '0') && (ch <= '9')) + return ch - '0'; + ch = tolower(ch); + if ((ch >= 'a') && (ch <= 'f')) + return ch - 'a' + 10; + return -1; +} +EXPORT_SYMBOL(hex_to_bin); + +/** + * hex2bin - convert an ascii hexadecimal string to its binary representation + * @dst: binary result + * @src: ascii hexadecimal string + * @count: result length + * + * Return 0 on success, -1 in case of bad input. + */ +int hex2bin(u8 *dst, const char *src, size_t count) +{ + while (count--) { + int hi = hex_to_bin(*src++); + int lo = hex_to_bin(*src++); + + if ((hi < 0) || (lo < 0)) + return -1; + + *dst++ = (hi << 4) | lo; + } + return 0; +} +EXPORT_SYMBOL(hex2bin); + +/** + * bin2hex - convert binary data to an ascii hexadecimal string + * @dst: ascii hexadecimal result + * @src: binary data + * @count: binary data length + */ +char *bin2hex(char *dst, const void *src, size_t count) +{ + const unsigned char *_src = src; + + while (count--) + dst = hex_byte_pack(dst, *_src++); + return dst; +} +EXPORT_SYMBOL(bin2hex); + +/** + * 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), true); + * + * example output buffer: + * 40 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e 4f @ABCDEFGHIJKLMNO + * + * Return: + * The amount of bytes placed in the buffer without terminating NUL. If the + * output was truncated, then the return value is the number of bytes + * (excluding the terminating NUL) which would have been written to the final + * string if enough space had been available. + */ +int 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; + int ngroups; + u8 ch; + int j, lx = 0; + int ascii_column; + int ret; + + if (rowsize != 16 && rowsize != 32) + rowsize = 16; + + if (len > rowsize) /* limit to one line at a time */ + len = rowsize; + if (!is_power_of_2(groupsize) || groupsize > 8) + groupsize = 1; + if ((len % groupsize) != 0) /* no mixed size output */ + groupsize = 1; + + ngroups = len / groupsize; + ascii_column = rowsize * 2 + rowsize / groupsize + 1; + + if (!linebuflen) + goto overflow1; + + if (!len) + goto nil; + + if (groupsize == 8) { + const u64 *ptr8 = buf; + + for (j = 0; j < ngroups; j++) { + ret = snprintf(linebuf + lx, linebuflen - lx, + "%s%16.16llx", j ? " " : "", + (unsigned long long)*(ptr8 + j)); + if (ret >= linebuflen - lx) + goto overflow1; + lx += ret; + } + } else if (groupsize == 4) { + const u32 *ptr4 = buf; + + for (j = 0; j < ngroups; j++) { + ret = snprintf(linebuf + lx, linebuflen - lx, + "%s%8.8x", j ? " " : "", + *(ptr4 + j)); + if (ret >= linebuflen - lx) + goto overflow1; + lx += ret; + } + } else if (groupsize == 2) { + const u16 *ptr2 = buf; + + for (j = 0; j < ngroups; j++) { + ret = snprintf(linebuf + lx, linebuflen - lx, + "%s%4.4x", j ? " " : "", + *(ptr2 + j)); + if (ret >= linebuflen - lx) + goto overflow1; + lx += ret; + } + } else { + for (j = 0; j < len; j++) { + if (linebuflen < lx + 3) + goto overflow2; + ch = ptr[j]; + linebuf[lx++] = hex_asc_hi(ch); + linebuf[lx++] = hex_asc_lo(ch); + linebuf[lx++] = ' '; + } + if (j) + lx--; + } + if (!ascii) + goto nil; + + while (lx < ascii_column) { + if (linebuflen < lx + 2) + goto overflow2; + linebuf[lx++] = ' '; + } + for (j = 0; j < len; j++) { + if (linebuflen < lx + 2) + goto overflow2; + ch = ptr[j]; + linebuf[lx++] = (isascii(ch) && isprint(ch)) ? ch : '.'; + } +nil: + linebuf[lx] = '\0'; + return lx; +overflow2: + linebuf[lx++] = '\0'; +overflow1: + return ascii ? ascii_column + len : (groupsize * 2 + 1) * ngroups - 1; +} +EXPORT_SYMBOL(hex_dump_to_buffer); + +#ifdef CONFIG_PRINTK +/** + * 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, true); + * + * 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[32 * 3 + 2 + 32 + 1]; + + 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, 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); + +#if !defined(CONFIG_DYNAMIC_DEBUG) +/** + * 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, true); +} +EXPORT_SYMBOL(print_hex_dump_bytes); +#endif /* !defined(CONFIG_DYNAMIC_DEBUG) */ +#endif /* defined(CONFIG_PRINTK) */ |