diff options
Diffstat (limited to 'fs/cachefiles/key.c')
-rw-r--r-- | fs/cachefiles/key.c | 155 |
1 files changed, 0 insertions, 155 deletions
diff --git a/fs/cachefiles/key.c b/fs/cachefiles/key.c deleted file mode 100644 index 7f94efc97e23..000000000000 --- a/fs/cachefiles/key.c +++ /dev/null @@ -1,155 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* Key to pathname encoder - * - * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. - * Written by David Howells (dhowells@redhat.com) - */ - -#include <linux/slab.h> -#include "internal.h" - -static const char cachefiles_charmap[64] = - "0123456789" /* 0 - 9 */ - "abcdefghijklmnopqrstuvwxyz" /* 10 - 35 */ - "ABCDEFGHIJKLMNOPQRSTUVWXYZ" /* 36 - 61 */ - "_-" /* 62 - 63 */ - ; - -static const char cachefiles_filecharmap[256] = { - /* we skip space and tab and control chars */ - [33 ... 46] = 1, /* '!' -> '.' */ - /* we skip '/' as it's significant to pathwalk */ - [48 ... 127] = 1, /* '0' -> '~' */ -}; - -/* - * turn the raw key into something cooked - * - the raw key should include the length in the two bytes at the front - * - the key may be up to 514 bytes in length (including the length word) - * - "base64" encode the strange keys, mapping 3 bytes of raw to four of - * cooked - * - need to cut the cooked key into 252 char lengths (189 raw bytes) - */ -char *cachefiles_cook_key(const u8 *raw, int keylen, uint8_t type) -{ - unsigned char csum, ch; - unsigned int acc; - char *key; - int loop, len, max, seg, mark, print; - - _enter(",%d", keylen); - - BUG_ON(keylen < 2 || keylen > 514); - - csum = raw[0] + raw[1]; - print = 1; - for (loop = 2; loop < keylen; loop++) { - ch = raw[loop]; - csum += ch; - print &= cachefiles_filecharmap[ch]; - } - - if (print) { - /* if the path is usable ASCII, then we render it directly */ - max = keylen - 2; - max += 2; /* two base64'd length chars on the front */ - max += 5; /* @checksum/M */ - max += 3 * 2; /* maximum number of segment dividers (".../M") - * is ((514 + 251) / 252) = 3 - */ - max += 1; /* NUL on end */ - } else { - /* calculate the maximum length of the cooked key */ - keylen = (keylen + 2) / 3; - - max = keylen * 4; - max += 5; /* @checksum/M */ - max += 3 * 2; /* maximum number of segment dividers (".../M") - * is ((514 + 188) / 189) = 3 - */ - max += 1; /* NUL on end */ - } - - max += 1; /* 2nd NUL on end */ - - _debug("max: %d", max); - - key = kmalloc(max, cachefiles_gfp); - if (!key) - return NULL; - - len = 0; - - /* build the cooked key */ - sprintf(key, "@%02x%c+", (unsigned) csum, 0); - len = 5; - mark = len - 1; - - if (print) { - acc = *(uint16_t *) raw; - raw += 2; - - key[len + 1] = cachefiles_charmap[acc & 63]; - acc >>= 6; - key[len] = cachefiles_charmap[acc & 63]; - len += 2; - - seg = 250; - for (loop = keylen; loop > 0; loop--) { - if (seg <= 0) { - key[len++] = '\0'; - mark = len; - key[len++] = '+'; - seg = 252; - } - - key[len++] = *raw++; - ASSERT(len < max); - } - - switch (type) { - case FSCACHE_COOKIE_TYPE_INDEX: type = 'I'; break; - case FSCACHE_COOKIE_TYPE_DATAFILE: type = 'D'; break; - default: type = 'S'; break; - } - } else { - seg = 252; - for (loop = keylen; loop > 0; loop--) { - if (seg <= 0) { - key[len++] = '\0'; - mark = len; - key[len++] = '+'; - seg = 252; - } - - acc = *raw++; - acc |= *raw++ << 8; - acc |= *raw++ << 16; - - _debug("acc: %06x", acc); - - key[len++] = cachefiles_charmap[acc & 63]; - acc >>= 6; - key[len++] = cachefiles_charmap[acc & 63]; - acc >>= 6; - key[len++] = cachefiles_charmap[acc & 63]; - acc >>= 6; - key[len++] = cachefiles_charmap[acc & 63]; - - ASSERT(len < max); - } - - switch (type) { - case FSCACHE_COOKIE_TYPE_INDEX: type = 'J'; break; - case FSCACHE_COOKIE_TYPE_DATAFILE: type = 'E'; break; - default: type = 'T'; break; - } - } - - key[mark] = type; - key[len++] = 0; - key[len] = 0; - - _leave(" = %s %d", key, len); - return key; -} |