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Diffstat (limited to 'lib/util/data_blob.c')
-rw-r--r-- | lib/util/data_blob.c | 297 |
1 files changed, 297 insertions, 0 deletions
diff --git a/lib/util/data_blob.c b/lib/util/data_blob.c new file mode 100644 index 0000000..677f7c1 --- /dev/null +++ b/lib/util/data_blob.c @@ -0,0 +1,297 @@ +/* + Unix SMB/CIFS implementation. + Easy management of byte-length data + Copyright (C) Andrew Tridgell 2001 + Copyright (C) Andrew Bartlett 2001 + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ + +#include "replace.h" +#include "attr.h" +#include "data_blob.h" +#include "lib/util/samba_util.h" + +const DATA_BLOB data_blob_null = { NULL, 0 }; + +/** + * @file + * @brief Manipulation of arbitrary data blobs + **/ + +/** + construct a data blob, must be freed with data_blob_free() + you can pass NULL for p and get a blank data blob +**/ +_PUBLIC_ DATA_BLOB data_blob_named(const void *p, size_t length, const char *name) +{ + return data_blob_talloc_named(NULL, p, length, name); +} + +/** + construct a data blob, using supplied TALLOC_CTX +**/ +_PUBLIC_ DATA_BLOB data_blob_talloc_named(TALLOC_CTX *mem_ctx, const void *p, size_t length, const char *name) +{ + DATA_BLOB ret; + + if (p == NULL && length == 0) { + ZERO_STRUCT(ret); + return ret; + } + + if (p) { + ret.data = (uint8_t *)talloc_memdup(mem_ctx, p, length); + } else { + ret.data = talloc_array(mem_ctx, uint8_t, length); + } + if (ret.data == NULL) { + ret.length = 0; + return ret; + } + talloc_set_name_const(ret.data, name); + ret.length = length; + return ret; +} + +/** + construct a zero data blob, using supplied TALLOC_CTX. + use this sparingly as it initialises data - better to initialise + yourself if you want specific data in the blob +**/ +_PUBLIC_ DATA_BLOB data_blob_talloc_zero(TALLOC_CTX *mem_ctx, size_t length) +{ + DATA_BLOB blob = data_blob_talloc(mem_ctx, NULL, length); + data_blob_clear(&blob); + return blob; +} + +/** +free a data blob +**/ +_PUBLIC_ void data_blob_free(DATA_BLOB *d) +{ + if (d) { + TALLOC_FREE(d->data); + d->length = 0; + } +} + +/** +clear a DATA_BLOB's contents +**/ +_PUBLIC_ void data_blob_clear(DATA_BLOB *d) +{ + if (d->data) { + memset_s(d->data, d->length, 0, d->length); + } +} + +/** +free a data blob and clear its contents +**/ +_PUBLIC_ void data_blob_clear_free(DATA_BLOB *d) +{ + data_blob_clear(d); + data_blob_free(d); +} + + +/** +check if two data blobs are equal +**/ +_PUBLIC_ int data_blob_cmp(const DATA_BLOB *d1, const DATA_BLOB *d2) +{ + int ret; + if (d1->data == NULL && d2->data != NULL) { + return -1; + } + if (d1->data != NULL && d2->data == NULL) { + return 1; + } + if (d1->data == d2->data) { + return d1->length - d2->length; + } + ret = memcmp(d1->data, d2->data, MIN(d1->length, d2->length)); + if (ret == 0) { + return d1->length - d2->length; + } + return ret; +} + +/** +check if two data blobs are equal, where the time taken should not depend on the +contents of either blob. +**/ +_PUBLIC_ bool data_blob_equal_const_time(const DATA_BLOB *d1, const DATA_BLOB *d2) +{ + bool ret; + if (d1->data == NULL && d2->data != NULL) { + return false; + } + if (d1->data != NULL && d2->data == NULL) { + return false; + } + if (d1->length != d2->length) { + return false; + } + if (d1->data == d2->data) { + return true; + } + ret = mem_equal_const_time(d1->data, d2->data, d1->length); + return ret; +} + +/** +print the data_blob as hex string +**/ +_PUBLIC_ char *data_blob_hex_string_lower(TALLOC_CTX *mem_ctx, const DATA_BLOB *blob) +{ + size_t i; + char *hex_string; + + hex_string = talloc_array(mem_ctx, char, (blob->length*2)+1); + if (!hex_string) { + return NULL; + } + + /* this must be lowercase or w2k8 cannot join a samba domain, + as this routine is used to encode extended DNs and windows + only accepts lowercase hexadecimal numbers */ + for (i = 0; i < blob->length; i++) + slprintf(&hex_string[i*2], 3, "%02x", blob->data[i]); + + hex_string[(blob->length*2)] = '\0'; + return hex_string; +} + +_PUBLIC_ char *data_blob_hex_string_upper(TALLOC_CTX *mem_ctx, const DATA_BLOB *blob) +{ + size_t i; + char *hex_string; + + hex_string = talloc_array(mem_ctx, char, (blob->length*2)+1); + if (!hex_string) { + return NULL; + } + + for (i = 0; i < blob->length; i++) + slprintf(&hex_string[i*2], 3, "%02X", blob->data[i]); + + hex_string[(blob->length*2)] = '\0'; + return hex_string; +} + +/** + useful for constructing data blobs in test suites, while + avoiding const warnings +**/ +_PUBLIC_ DATA_BLOB data_blob_string_const(const char *str) +{ + DATA_BLOB blob; + blob.data = discard_const_p(uint8_t, str); + blob.length = str ? strlen(str) : 0; + return blob; +} + +/** + useful for constructing data blobs in test suites, while + avoiding const warnings +**/ +_PUBLIC_ DATA_BLOB data_blob_string_const_null(const char *str) +{ + DATA_BLOB blob; + blob.data = discard_const_p(uint8_t, str); + blob.length = str ? strlen(str)+1 : 0; + return blob; +} + +/** + * Create a new data blob from const data + */ + +_PUBLIC_ DATA_BLOB data_blob_const(const void *p, size_t length) +{ + DATA_BLOB blob; + blob.data = discard_const_p(uint8_t, p); + blob.length = length; + return blob; +} + + +/** + realloc a data_blob +**/ +_PUBLIC_ bool data_blob_realloc(TALLOC_CTX *mem_ctx, DATA_BLOB *blob, size_t length) +{ + uint8_t *tmp = talloc_realloc(mem_ctx, blob->data, uint8_t, length); + if (tmp == NULL) { + return false; + } + blob->data = tmp; + blob->length = length; + return true; +} + + +/** + append some data to a data blob +**/ +_PUBLIC_ bool data_blob_append(TALLOC_CTX *mem_ctx, DATA_BLOB *blob, + const void *p, size_t length) +{ + size_t old_len = blob->length; + size_t new_len = old_len + length; + + if (length == 0) { + return true; + } + + if (new_len < length || new_len < old_len) { + return false; + } + + if ((const uint8_t *)p + length < (const uint8_t *)p) { + return false; + } + + if (!data_blob_realloc(mem_ctx, blob, new_len)) { + return false; + } + + memcpy(blob->data + old_len, p, length); + return true; +} + +/** + pad the length of a data blob to a multiple of + 'pad'. 'pad' must be a power of two. +**/ +_PUBLIC_ bool data_blob_pad(TALLOC_CTX *mem_ctx, DATA_BLOB *blob, + size_t pad) +{ + size_t old_len = blob->length; + size_t new_len = (old_len + pad - 1) & ~(pad - 1); + + if (new_len < old_len) { + return false; + } + + if (!data_blob_realloc(mem_ctx, blob, new_len)) { + return false; + } + + memset(blob->data + old_len, 0, new_len - old_len); + return true; +} |