/* zip_buffer.c -- bounds checked access to memory buffer Copyright (C) 2014-2016 Dieter Baron and Thomas Klausner This file is part of libzip, a library to manipulate ZIP archives. The authors can be contacted at <libzip@nih.at> Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. The names of the authors may not be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include <stdlib.h> #include <string.h> #include "zipint.h" zip_uint8_t * _zip_buffer_data(zip_buffer_t *buffer) { return buffer->data; } void _zip_buffer_free(zip_buffer_t *buffer) { if (buffer == NULL) { return; } if (buffer->free_data) { free(buffer->data); } free(buffer); } bool _zip_buffer_eof(zip_buffer_t *buffer) { return buffer->ok && buffer->offset == buffer->size; } zip_uint8_t * _zip_buffer_get(zip_buffer_t *buffer, zip_uint64_t length) { zip_uint8_t *data; data = _zip_buffer_peek(buffer, length); if (data != NULL) { buffer->offset += length; } return data; } zip_uint16_t _zip_buffer_get_16(zip_buffer_t *buffer) { zip_uint8_t *data = _zip_buffer_get(buffer, 2); if (data == NULL) { return 0; } return (zip_uint16_t)(data[0] + (data[1] << 8)); } zip_uint32_t _zip_buffer_get_32(zip_buffer_t *buffer) { zip_uint8_t *data = _zip_buffer_get(buffer, 4); if (data == NULL) { return 0; } return ((((((zip_uint32_t)data[3] << 8) + data[2]) << 8) + data[1]) << 8) + data[0]; } zip_uint64_t _zip_buffer_get_64(zip_buffer_t *buffer) { zip_uint8_t *data = _zip_buffer_get(buffer, 8); if (data == NULL) { return 0; } return ((zip_uint64_t)data[7] << 56) + ((zip_uint64_t)data[6] << 48) + ((zip_uint64_t)data[5] << 40) + ((zip_uint64_t)data[4] << 32) + ((zip_uint64_t)data[3] << 24) + ((zip_uint64_t)data[2] << 16) + ((zip_uint64_t)data[1] << 8) + (zip_uint64_t)data[0]; } zip_uint8_t _zip_buffer_get_8(zip_buffer_t *buffer) { zip_uint8_t *data = _zip_buffer_get(buffer, 1); if (data == NULL) { return 0; } return data[0]; } zip_uint64_t _zip_buffer_left(zip_buffer_t *buffer) { return buffer->ok ? buffer->size - buffer->offset : 0; } zip_uint64_t _zip_buffer_read(zip_buffer_t *buffer, zip_uint8_t *data, zip_uint64_t length) { if (_zip_buffer_left(buffer) < length) { length = _zip_buffer_left(buffer); } memcpy(data, _zip_buffer_get(buffer, length), length); return length; } zip_buffer_t * _zip_buffer_new(zip_uint8_t *data, zip_uint64_t size) { bool free_data = (data == NULL); zip_buffer_t *buffer; if (data == NULL) { if ((data = (zip_uint8_t *)malloc(size)) == NULL) { return NULL; } } if ((buffer = (zip_buffer_t *)malloc(sizeof(*buffer))) == NULL) { if (free_data) { free(data); } return NULL; } buffer->ok = true; buffer->data = data; buffer->size = size; buffer->offset = 0; buffer->free_data = free_data; return buffer; } zip_buffer_t * _zip_buffer_new_from_source(zip_source_t *src, zip_uint64_t size, zip_uint8_t *buf, zip_error_t *error) { zip_buffer_t *buffer; if ((buffer = _zip_buffer_new(buf, size)) == NULL) { zip_error_set(error, ZIP_ER_MEMORY, 0); return NULL; } if (_zip_read(src, buffer->data, size, error) < 0) { _zip_buffer_free(buffer); return NULL; } return buffer; } zip_uint64_t _zip_buffer_offset(zip_buffer_t *buffer) { return buffer->ok ? buffer->offset : 0; } bool _zip_buffer_ok(zip_buffer_t *buffer) { return buffer->ok; } zip_uint8_t * _zip_buffer_peek(zip_buffer_t *buffer, zip_uint64_t length) { zip_uint8_t *data; if (!buffer->ok || buffer->offset + length < length || buffer->offset + length > buffer->size) { buffer->ok = false; return NULL; } data = buffer->data + buffer->offset; return data; } int _zip_buffer_put(zip_buffer_t *buffer, const void *src, size_t length) { zip_uint8_t *dst = _zip_buffer_get(buffer, length); if (dst == NULL) { return -1; } memcpy(dst, src, length); return 0; } int _zip_buffer_put_16(zip_buffer_t *buffer, zip_uint16_t i) { zip_uint8_t *data = _zip_buffer_get(buffer, 2); if (data == NULL) { return -1; } data[0] = (zip_uint8_t)(i & 0xff); data[1] = (zip_uint8_t)((i >> 8) & 0xff); return 0; } int _zip_buffer_put_32(zip_buffer_t *buffer, zip_uint32_t i) { zip_uint8_t *data = _zip_buffer_get(buffer, 4); if (data == NULL) { return -1; } data[0] = (zip_uint8_t)(i & 0xff); data[1] = (zip_uint8_t)((i >> 8) & 0xff); data[2] = (zip_uint8_t)((i >> 16) & 0xff); data[3] = (zip_uint8_t)((i >> 24) & 0xff); return 0; } int _zip_buffer_put_64(zip_buffer_t *buffer, zip_uint64_t i) { zip_uint8_t *data = _zip_buffer_get(buffer, 8); if (data == NULL) { return -1; } data[0] = (zip_uint8_t)(i & 0xff); data[1] = (zip_uint8_t)((i >> 8) & 0xff); data[2] = (zip_uint8_t)((i >> 16) & 0xff); data[3] = (zip_uint8_t)((i >> 24) & 0xff); data[4] = (zip_uint8_t)((i >> 32) & 0xff); data[5] = (zip_uint8_t)((i >> 40) & 0xff); data[6] = (zip_uint8_t)((i >> 48) & 0xff); data[7] = (zip_uint8_t)((i >> 56) & 0xff); return 0; } int _zip_buffer_put_8(zip_buffer_t *buffer, zip_uint8_t i) { zip_uint8_t *data = _zip_buffer_get(buffer, 1); if (data == NULL) { return -1; } data[0] = i; return 0; } int _zip_buffer_set_offset(zip_buffer_t *buffer, zip_uint64_t offset) { if (offset > buffer->size) { buffer->ok = false; return -1; } buffer->ok = true; buffer->offset = offset; return 0; } int _zip_buffer_skip(zip_buffer_t *buffer, zip_uint64_t length) { zip_uint64_t offset = buffer->offset + length; if (offset < buffer->offset) { buffer->ok = false; return -1; } return _zip_buffer_set_offset(buffer, offset); } zip_uint64_t _zip_buffer_size(zip_buffer_t *buffer) { return buffer->size; }