/* Copyright 2015 The Chromium OS Authors. All rights reserved. * Use of this source code is governed by a BSD-style license that can be * found in the LICENSE file. * * Secure storage APIs - kernel version space */ #include "2sysincludes.h" #include "2common.h" #include "2crc8.h" #include "2misc.h" #include "2secdata.h" int vb2_secdatak_check_crc(const struct vb2_context *ctx) { const struct vb2_secdatak *sec = (const struct vb2_secdatak *)ctx->secdatak; /* Verify CRC */ if (sec->crc8 != vb2_crc8(sec, offsetof(struct vb2_secdatak, crc8))) return VB2_ERROR_SECDATAK_CRC; return VB2_SUCCESS; } int vb2_secdatak_create(struct vb2_context *ctx) { struct vb2_secdatak *sec = (struct vb2_secdatak *)ctx->secdatak; /* Clear the entire struct */ memset(sec, 0, sizeof(*sec)); /* Set to current version */ sec->struct_version = VB2_SECDATAK_VERSION; /* Set UID */ sec->uid = VB2_SECDATAK_UID; /* Calculate initial CRC */ sec->crc8 = vb2_crc8(sec, offsetof(struct vb2_secdatak, crc8)); ctx->flags |= VB2_CONTEXT_SECDATAK_CHANGED; return VB2_SUCCESS; } int vb2_secdatak_init(struct vb2_context *ctx) { struct vb2_secdatak *sec = (struct vb2_secdatak *)ctx->secdatak; struct vb2_shared_data *sd = vb2_get_sd(ctx); int rv; rv = vb2_secdatak_check_crc(ctx); if (rv) return rv; /* Make sure the UID is correct */ if (sec->uid != VB2_SECDATAK_UID) return VB2_ERROR_SECDATAK_UID; /* Set status flag */ sd->status |= VB2_SD_STATUS_SECDATAK_INIT; /* TODO: unit test for that */ return VB2_SUCCESS; } int vb2_secdatak_get(struct vb2_context *ctx, enum vb2_secdatak_param param, uint32_t *dest) { struct vb2_secdatak *sec = (struct vb2_secdatak *)ctx->secdatak; if (!(vb2_get_sd(ctx)->status & VB2_SD_STATUS_SECDATAK_INIT)) return VB2_ERROR_SECDATAK_GET_UNINITIALIZED; switch(param) { case VB2_SECDATAK_VERSIONS: *dest = sec->kernel_versions; return VB2_SUCCESS; default: return VB2_ERROR_SECDATAK_GET_PARAM; } } int vb2_secdatak_set(struct vb2_context *ctx, enum vb2_secdatak_param param, uint32_t value) { struct vb2_secdatak *sec = (struct vb2_secdatak *)ctx->secdatak; uint32_t now; if (!(vb2_get_sd(ctx)->status & VB2_SD_STATUS_SECDATAK_INIT)) return VB2_ERROR_SECDATAK_SET_UNINITIALIZED; /* If not changing the value, don't regenerate the CRC. */ if (vb2_secdatak_get(ctx, param, &now) == VB2_SUCCESS && now == value) return VB2_SUCCESS; switch(param) { case VB2_SECDATAK_VERSIONS: sec->kernel_versions = value; break; default: return VB2_ERROR_SECDATAK_SET_PARAM; } /* Regenerate CRC */ sec->crc8 = vb2_crc8(sec, offsetof(struct vb2_secdatak, crc8)); ctx->flags |= VB2_CONTEXT_SECDATAK_CHANGED; return VB2_SUCCESS; }