1 /* 2 * Copyright (C) 2016 The Android Open Source Project 3 * 4 * Permission is hereby granted, free of charge, to any person 5 * obtaining a copy of this software and associated documentation 6 * files (the "Software"), to deal in the Software without 7 * restriction, including without limitation the rights to use, copy, 8 * modify, merge, publish, distribute, sublicense, and/or sell copies 9 * of the Software, and to permit persons to whom the Software is 10 * furnished to do so, subject to the following conditions: 11 * 12 * The above copyright notice and this permission notice shall be 13 * included in all copies or substantial portions of the Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 18 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 19 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 20 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 21 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 22 * SOFTWARE. 23 */ 24 25 #include "avb_kernel_cmdline_descriptor.h" 26 #include "avb_util.h" 27 28 bool avb_kernel_cmdline_descriptor_validate_and_byteswap( 29 const AvbKernelCmdlineDescriptor* src, AvbKernelCmdlineDescriptor* dest) { 30 uint64_t expected_size; 31 32 avb_memcpy(dest, src, sizeof(AvbKernelCmdlineDescriptor)); 33 34 if (!avb_descriptor_validate_and_byteswap((const AvbDescriptor*)src, 35 (AvbDescriptor*)dest)) 36 return false; 37 38 if (dest->parent_descriptor.tag != AVB_DESCRIPTOR_TAG_KERNEL_CMDLINE) { 39 avb_error("Invalid tag for kernel cmdline descriptor.\n"); 40 return false; 41 } 42 43 dest->flags = avb_be32toh(dest->flags); 44 dest->kernel_cmdline_length = avb_be32toh(dest->kernel_cmdline_length); 45 46 /* Check that kernel_cmdline is fully contained. */ 47 expected_size = sizeof(AvbKernelCmdlineDescriptor) - sizeof(AvbDescriptor); 48 if (!avb_safe_add_to(&expected_size, dest->kernel_cmdline_length)) { 49 avb_error("Overflow while adding up sizes.\n"); 50 return false; 51 } 52 if (expected_size > dest->parent_descriptor.num_bytes_following) { 53 avb_error("Descriptor payload size overflow.\n"); 54 return false; 55 } 56 57 return true; 58 } 59
