diff options
Diffstat (limited to 'firmware/2lib/2secdata.c')
-rw-r--r-- | firmware/2lib/2secdata.c | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/firmware/2lib/2secdata.c b/firmware/2lib/2secdata.c new file mode 100644 index 00000000..668bc507 --- /dev/null +++ b/firmware/2lib/2secdata.c @@ -0,0 +1,115 @@ +/* Copyright (c) 2014 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 + */ + +#include "2sysincludes.h" +#include "2common.h" +#include "2crc8.h" +#include "2misc.h" +#include "2secdata.h" + +int vb2_secdata_check_crc(const struct vb2_context *ctx) +{ + const struct vb2_secdata *sec = + (const struct vb2_secdata *)ctx->secdata; + + /* Verify CRC */ + if (sec->crc8 != vb2_crc8(sec, offsetof(struct vb2_secdata, crc8))) + return VB2_ERROR_BAD_SECDATA; + + return VB2_SUCCESS; +} + +int vb2_secdata_create(struct vb2_context *ctx) +{ + struct vb2_secdata *sec = (struct vb2_secdata *)ctx->secdata; + + /* Clear the entire struct */ + memset(sec, 0, sizeof(*sec)); + + /* Set to current version */ + sec->struct_version = VB2_SECDATA_VERSION; + + /* Calculate initial CRC */ + sec->crc8 = vb2_crc8(sec, offsetof(struct vb2_secdata, crc8)); + ctx->flags |= VB2_CONTEXT_SECDATA_CHANGED; + return VB2_SUCCESS; +} + +int vb2_secdata_init(struct vb2_context *ctx) +{ + struct vb2_shared_data *sd = vb2_get_sd(ctx); + struct vb2_secdata *sec = (struct vb2_secdata *)ctx->secdata; + int rv; + + /* Data must be new enough to have a CRC */ + if (sec->struct_version < 2) + return VB2_ERROR_BAD_SECDATA; + + rv = vb2_secdata_check_crc(ctx); + if (rv) + return rv; + + /* Set status flag */ + sd->status |= VB2_SD_STATUS_SECDATA_INIT; + // TODO: unit test for that + + return VB2_SUCCESS; +} + +int vb2_secdata_get(struct vb2_context *ctx, + enum vb2_secdata_param param, + uint32_t *dest) +{ + struct vb2_secdata *sec = (struct vb2_secdata *)ctx->secdata; + + switch(param) { + case VB2_SECDATA_FLAGS: + *dest = sec->flags; + return VB2_SUCCESS; + + case VB2_SECDATA_VERSIONS: + *dest = sec->fw_versions; + return VB2_SUCCESS; + + default: + return VB2_ERROR_UNKNOWN; + } +} + +int vb2_secdata_set(struct vb2_context *ctx, + enum vb2_secdata_param param, + uint32_t value) +{ + struct vb2_secdata *sec = (struct vb2_secdata *)ctx->secdata; + uint32_t now; + + /* If not changing the value, don't regenerate the CRC. */ + if (vb2_secdata_get(ctx, param, &now) == VB2_SUCCESS && now == value) + return VB2_SUCCESS; + + switch(param) { + case VB2_SECDATA_FLAGS: + /* Make sure flags is in valid range */ + if (value > 0xff) + return VB2_ERROR_UNKNOWN; + + sec->flags = value; + break; + + case VB2_SECDATA_VERSIONS: + sec->fw_versions = value; + break; + + default: + return VB2_ERROR_UNKNOWN; + } + + /* Regenerate CRC */ + sec->crc8 = vb2_crc8(sec, offsetof(struct vb2_secdata, crc8)); + ctx->flags |= VB2_CONTEXT_SECDATA_CHANGED; + return VB2_SUCCESS; +} |