1*4882a593Smuzhiyun /* 2*4882a593Smuzhiyun * Copyright (C) 2016 The Android Open Source Project 3*4882a593Smuzhiyun * 4*4882a593Smuzhiyun * Permission is hereby granted, free of charge, to any person 5*4882a593Smuzhiyun * obtaining a copy of this software and associated documentation 6*4882a593Smuzhiyun * files (the "Software"), to deal in the Software without 7*4882a593Smuzhiyun * restriction, including without limitation the rights to use, copy, 8*4882a593Smuzhiyun * modify, merge, publish, distribute, sublicense, and/or sell copies 9*4882a593Smuzhiyun * of the Software, and to permit persons to whom the Software is 10*4882a593Smuzhiyun * furnished to do so, subject to the following conditions: 11*4882a593Smuzhiyun * 12*4882a593Smuzhiyun * The above copyright notice and this permission notice shall be 13*4882a593Smuzhiyun * included in all copies or substantial portions of the Software. 14*4882a593Smuzhiyun * 15*4882a593Smuzhiyun * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 16*4882a593Smuzhiyun * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 17*4882a593Smuzhiyun * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 18*4882a593Smuzhiyun * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 19*4882a593Smuzhiyun * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 20*4882a593Smuzhiyun * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 21*4882a593Smuzhiyun * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 22*4882a593Smuzhiyun * SOFTWARE. 23*4882a593Smuzhiyun */ 24*4882a593Smuzhiyun 25*4882a593Smuzhiyun /* 26*4882a593Smuzhiyun #if !defined(AVB_INSIDE_LIBAVB_H) && !defined(AVB_COMPILATION) 27*4882a593Smuzhiyun #error "Never include this file directly, include libavb.h instead." 28*4882a593Smuzhiyun #endif 29*4882a593Smuzhiyun */ 30*4882a593Smuzhiyun 31*4882a593Smuzhiyun #ifndef AVB_PROPERTY_DESCRIPTOR_H_ 32*4882a593Smuzhiyun #define AVB_PROPERTY_DESCRIPTOR_H_ 33*4882a593Smuzhiyun 34*4882a593Smuzhiyun #include <android_avb/avb_descriptor.h> 35*4882a593Smuzhiyun 36*4882a593Smuzhiyun #ifdef __cplusplus 37*4882a593Smuzhiyun extern "C" { 38*4882a593Smuzhiyun #endif 39*4882a593Smuzhiyun 40*4882a593Smuzhiyun /* A descriptor for properties (free-form key/value pairs). 41*4882a593Smuzhiyun * 42*4882a593Smuzhiyun * Following this struct are |key_num_bytes| bytes of key data, 43*4882a593Smuzhiyun * followed by a NUL byte, then |value_num_bytes| bytes of value data, 44*4882a593Smuzhiyun * followed by a NUL byte and then enough padding to make the combined 45*4882a593Smuzhiyun * size a multiple of 8. 46*4882a593Smuzhiyun */ 47*4882a593Smuzhiyun typedef struct AvbPropertyDescriptor { 48*4882a593Smuzhiyun AvbDescriptor parent_descriptor; 49*4882a593Smuzhiyun uint64_t key_num_bytes; 50*4882a593Smuzhiyun uint64_t value_num_bytes; 51*4882a593Smuzhiyun } AVB_ATTR_PACKED AvbPropertyDescriptor; 52*4882a593Smuzhiyun 53*4882a593Smuzhiyun /* Copies |src| to |dest| and validates, byte-swapping fields in the 54*4882a593Smuzhiyun * process if needed. Returns true if valid, false if invalid. 55*4882a593Smuzhiyun * 56*4882a593Smuzhiyun * Data following the struct is not validated nor copied. 57*4882a593Smuzhiyun */ 58*4882a593Smuzhiyun bool avb_property_descriptor_validate_and_byteswap( 59*4882a593Smuzhiyun const AvbPropertyDescriptor* src, 60*4882a593Smuzhiyun AvbPropertyDescriptor* dest) AVB_ATTR_WARN_UNUSED_RESULT; 61*4882a593Smuzhiyun 62*4882a593Smuzhiyun /* Convenience function for looking up the value for a property with 63*4882a593Smuzhiyun * name |key| in a vbmeta image. If |key_size| is 0, |key| must be 64*4882a593Smuzhiyun * NUL-terminated. 65*4882a593Smuzhiyun * 66*4882a593Smuzhiyun * The |image_data| parameter must be a pointer to a vbmeta image of 67*4882a593Smuzhiyun * size |image_size|. 68*4882a593Smuzhiyun * 69*4882a593Smuzhiyun * This function returns a pointer to the value inside the passed-in 70*4882a593Smuzhiyun * image or NULL if not found. Note that the value is always 71*4882a593Smuzhiyun * guaranteed to be followed by a NUL byte. 72*4882a593Smuzhiyun * 73*4882a593Smuzhiyun * If the value was found and |out_value_size| is not NULL, the size 74*4882a593Smuzhiyun * of the value is returned there. 75*4882a593Smuzhiyun * 76*4882a593Smuzhiyun * This function is O(n) in number of descriptors so if you need to 77*4882a593Smuzhiyun * look up a lot of values, you may want to build a more efficient 78*4882a593Smuzhiyun * lookup-table by manually walking all descriptors using 79*4882a593Smuzhiyun * avb_descriptor_foreach(). 80*4882a593Smuzhiyun * 81*4882a593Smuzhiyun * Before using this function, you MUST verify |image_data| with 82*4882a593Smuzhiyun * avb_vbmeta_image_verify() and reject it unless it's signed by a 83*4882a593Smuzhiyun * known good public key. 84*4882a593Smuzhiyun */ 85*4882a593Smuzhiyun const char* avb_property_lookup(const uint8_t* image_data, 86*4882a593Smuzhiyun size_t image_size, 87*4882a593Smuzhiyun const char* key, 88*4882a593Smuzhiyun size_t key_size, 89*4882a593Smuzhiyun size_t* out_value_size) 90*4882a593Smuzhiyun AVB_ATTR_WARN_UNUSED_RESULT; 91*4882a593Smuzhiyun 92*4882a593Smuzhiyun /* Like avb_property_lookup() but parses the intial portions of the 93*4882a593Smuzhiyun * value as an unsigned 64-bit integer. Both decimal and hexadecimal 94*4882a593Smuzhiyun * representations (e.g. "0x2a") are supported. Returns false on 95*4882a593Smuzhiyun * failure and true on success. On success, the parsed value is 96*4882a593Smuzhiyun * returned in |out_value|. 97*4882a593Smuzhiyun */ 98*4882a593Smuzhiyun bool avb_property_lookup_uint64(const uint8_t* image_data, 99*4882a593Smuzhiyun size_t image_size, 100*4882a593Smuzhiyun const char* key, 101*4882a593Smuzhiyun size_t key_size, 102*4882a593Smuzhiyun uint64_t* out_value) 103*4882a593Smuzhiyun AVB_ATTR_WARN_UNUSED_RESULT; 104*4882a593Smuzhiyun 105*4882a593Smuzhiyun #ifdef __cplusplus 106*4882a593Smuzhiyun } 107*4882a593Smuzhiyun #endif 108*4882a593Smuzhiyun 109*4882a593Smuzhiyun #endif /* AVB_PROPERTY_DESCRIPTOR_H_ */ 110