diff options
Diffstat (limited to 'firmware/lib20/api_kernel.c')
| -rw-r--r-- | firmware/lib20/api_kernel.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/firmware/lib20/api_kernel.c b/firmware/lib20/api_kernel.c index 3748420f..1e96f281 100644 --- a/firmware/lib20/api_kernel.c +++ b/firmware/lib20/api_kernel.c @@ -16,6 +16,32 @@ #include "vb2_common.h" #include "vboot_struct.h" +int vb2api_is_developer_signed(struct vb2_context *ctx) +{ + struct vb2_shared_data *sd = vb2_get_sd(ctx); + + if (!sd->kernel_key_offset || !sd->kernel_key_size) { + VB2_REC_OR_DIE(ctx, "Cannot call this before kernel_phase1!\n"); + return 0; + } + + struct vb2_public_key key; + if (vb2_unpack_key(&key, vb2_member_of(sd, sd->kernel_key_offset))) + return 0; + + /* This is a debugging aid, not a security-relevant feature. There's no + reason to hardcode the whole key or waste time computing a hash. Just + spot check the starting bytes of the pseudorandom part of the key. */ + uint32_t devkey_n0inv = ctx->flags & VB2_CONTEXT_RECOVERY_MODE ? + 0x18cebcf5 : /* recovery_key.vbpubk @0x24 */ + 0xe0cd87d9; /* kernel_subkey.vbpubk @0x24 */ + + if (key.n0inv == devkey_n0inv) + return 1; + + return 0; +} + vb2_error_t vb2api_kernel_phase1(struct vb2_context *ctx) { struct vb2_shared_data *sd = vb2_get_sd(ctx); @@ -82,6 +108,9 @@ vb2_error_t vb2api_kernel_phase1(struct vb2_context *ctx) vb2_set_workbuf_used(ctx, vb2_offset_of(sd, wb.buf)); + if (vb2api_is_developer_signed(ctx)) + VB2_DEBUG("This is developer-signed firmware.\n"); + return VB2_SUCCESS; } |