diff options
Diffstat (limited to 'src/libstrongswan/chunk.c')
| -rw-r--r-- | src/libstrongswan/chunk.c | 135 |
1 files changed, 86 insertions, 49 deletions
diff --git a/src/libstrongswan/chunk.c b/src/libstrongswan/chunk.c index 565f48fb0..681581af9 100644 --- a/src/libstrongswan/chunk.c +++ b/src/libstrongswan/chunk.c @@ -1,4 +1,5 @@ /* + * Copyright (C) 2008 Tobias Brunner * Copyright (C) 2005-2006 Martin Willi * Copyright (C) 2005 Jan Hutter * Hochschule fuer Technik Rapperswil @@ -13,7 +14,7 @@ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * for more details. * - * $Id: chunk.c 4276 2008-08-22 10:44:51Z martin $ + * $Id: chunk.c 4784 2008-12-10 13:43:51Z tobias $ */ #include <stdio.h> @@ -26,6 +27,16 @@ #include <debug.h> #include <printf_hook.h> +/* required for chunk_hash */ +#undef get16bits +#if (defined(__GNUC__) && defined(__i386__)) +#define get16bits(d) (*((const u_int16_t*)(d))) +#endif +#if !defined (get16bits) +#define get16bits(d) ((((u_int32_t)(((const u_int8_t*)(d))[1])) << 8)\ + + (u_int32_t)(((const u_int8_t*)(d))[0]) ) +#endif + /** * Empty chunk. */ @@ -34,15 +45,6 @@ chunk_t chunk_empty = { NULL, 0 }; /** * Described in header. */ -chunk_t chunk_create(u_char *ptr, size_t len) -{ - chunk_t chunk = {ptr, len}; - return chunk; -} - -/** - * Described in header. - */ chunk_t chunk_create_clone(u_char *ptr, chunk_t chunk) { chunk_t clone = chunk_empty; @@ -132,7 +134,7 @@ chunk_t chunk_create_cat(u_char *ptr, const char* mode, ...) void chunk_split(chunk_t chunk, const char *mode, ...) { va_list chunks; - size_t len; + u_int len; chunk_t *ch; va_start(chunks, mode); @@ -142,7 +144,7 @@ void chunk_split(chunk_t chunk, const char *mode, ...) { break; } - len = va_arg(chunks, size_t); + len = va_arg(chunks, u_int); ch = va_arg(chunks, chunk_t*); /* a null chunk means skip len bytes */ if (ch == NULL) @@ -251,7 +253,7 @@ static char hexdig_lower[] = "0123456789abcdef"; */ chunk_t chunk_to_hex(chunk_t chunk, char *buf, bool uppercase) { - int i, len;; + int i, len; char *hexdig = hexdig_lower; if (uppercase) @@ -428,39 +430,6 @@ chunk_t chunk_from_base64(chunk_t base64, char *buf) /** * Described in header. */ -void chunk_free(chunk_t *chunk) -{ - free(chunk->ptr); - chunk->ptr = NULL; - chunk->len = 0; -} - -/** - * Described in header. - */ -void chunk_clear(chunk_t *chunk) -{ - memset(chunk->ptr, 0, chunk->len); - chunk_free(chunk); -} - -/** - * Described in header. - */ -chunk_t chunk_skip(chunk_t chunk, size_t bytes) -{ - if (chunk.len > bytes) - { - chunk.ptr += bytes; - chunk.len -= bytes; - return chunk; - } - return chunk_empty; -} - -/** - * Described in header. - */ int chunk_compare(chunk_t a, chunk_t b) { int compare_len = a.len - b.len; @@ -475,11 +444,79 @@ int chunk_compare(chunk_t a, chunk_t b) /** * Described in header. + * + * The implementation is based on Paul Hsieh's SuperFastHash: + * http://www.azillionmonkeys.com/qed/hash.html + */ +u_int32_t chunk_hash_inc(chunk_t chunk, u_int32_t hash) +{ + u_char *data = chunk.ptr; + size_t len = chunk.len; + u_int32_t tmp; + int rem; + + if (!len || data == NULL) + { + return 0; + } + + rem = len & 3; + len >>= 2; + + /* Main loop */ + for (; len > 0; --len) + { + hash += get16bits(data); + tmp = (get16bits(data + 2) << 11) ^ hash; + hash = (hash << 16) ^ tmp; + data += 2 * sizeof(u_int16_t); + hash += hash >> 11; + } + + /* Handle end cases */ + switch (rem) + { + case 3: + { + hash += get16bits(data); + hash ^= hash << 16; + hash ^= data[sizeof(u_int16_t)] << 18; + hash += hash >> 11; + break; + } + case 2: + { + hash += get16bits(data); + hash ^= hash << 11; + hash += hash >> 17; + break; + } + case 1: + { + hash += *data; + hash ^= hash << 10; + hash += hash >> 1; + break; + } + } + + /* Force "avalanching" of final 127 bits */ + hash ^= hash << 3; + hash += hash >> 5; + hash ^= hash << 4; + hash += hash >> 17; + hash ^= hash << 25; + hash += hash >> 6; + + return hash; +} + +/** + * Described in header. */ -bool chunk_equals(chunk_t a, chunk_t b) +u_int32_t chunk_hash(chunk_t chunk) { - return a.ptr != NULL && b.ptr != NULL && - a.len == b.len && memeq(a.ptr, b.ptr, a.len); + return chunk_hash_inc(chunk, chunk.len); } /** |