If capsule authentication is disabled and yet a capsule file is signed, its signature must be removed from image data to flush. Otherwise, the firmware will be corrupted after update.
Fixes: 04be98bd6bcf ("efi: capsule: Add support for uefi capsule authentication") Signed-off-by: AKASHI Takahiro takahiro.akashi@linaro.org --- v2: rebase v1 on top of Ilias's patch --- lib/efi_loader/efi_capsule.c | 70 +++++++++++++++++++++++++++++------- 1 file changed, 57 insertions(+), 13 deletions(-)
diff --git a/lib/efi_loader/efi_capsule.c b/lib/efi_loader/efi_capsule.c index 3c029378de0a..26990bc2df4a 100644 --- a/lib/efi_loader/efi_capsule.c +++ b/lib/efi_loader/efi_capsule.c @@ -218,6 +218,39 @@ skip: return NULL; }
+/** + * efi_remove_auth_hdr - remove authentication data from image + * @image: Pointer to pointer to Image + * @image_size: Pointer to Image size + * + * Remove the authentication data from image if possible. + * Update @image and @image_size. + * + * Return: status code + */ +static efi_status_t efi_remove_auth_hdr(void **image, efi_uintn_t *image_size) +{ + struct efi_firmware_image_authentication *auth_hdr; + efi_status_t ret = EFI_INVALID_PARAMETER; + + auth_hdr = (struct efi_firmware_image_authentication *)*image; + if (*image_size < sizeof(*auth_hdr)) + goto out; + + if (auth_hdr->auth_info.hdr.dwLength <= + offsetof(struct win_certificate_uefi_guid, cert_data)) + goto out; + + *image = (uint8_t *)*image + sizeof(auth_hdr->monotonic_count) + + auth_hdr->auth_info.hdr.dwLength; + *image_size = *image_size - auth_hdr->auth_info.hdr.dwLength - + sizeof(auth_hdr->monotonic_count); + + ret = EFI_SUCCESS; +out: + return ret; +} + #if defined(CONFIG_EFI_CAPSULE_AUTHENTICATE)
static int efi_get_public_key_data(void **pkey, efi_uintn_t *pkey_len) @@ -254,21 +287,15 @@ efi_status_t efi_capsule_authenticate(const void *capsule, efi_uintn_t capsule_s if (capsule == NULL || capsule_size == 0) goto out;
- auth_hdr = (struct efi_firmware_image_authentication *)capsule; - if (capsule_size < sizeof(*auth_hdr)) - goto out; - - if (auth_hdr->auth_info.hdr.dwLength <= - offsetof(struct win_certificate_uefi_guid, cert_data)) + *image = (uint8_t *)capsule; + *image_size = capsule_size; + if (efi_remove_auth_hdr(image, image_size) != EFI_SUCCESS) goto out;
+ auth_hdr = (struct efi_firmware_image_authentication *)capsule; if (guidcmp(&auth_hdr->auth_info.cert_type, &efi_guid_cert_type_pkcs7)) goto out;
- *image = (uint8_t *)capsule + sizeof(auth_hdr->monotonic_count) + - auth_hdr->auth_info.hdr.dwLength; - *image_size = capsule_size - auth_hdr->auth_info.hdr.dwLength - - sizeof(auth_hdr->monotonic_count); memcpy(&monotonic_count, &auth_hdr->monotonic_count, sizeof(monotonic_count));
@@ -348,7 +375,7 @@ static efi_status_t efi_capsule_update_firmware( { struct efi_firmware_management_capsule_header *capsule; struct efi_firmware_management_capsule_image_header *image; - size_t capsule_size; + size_t capsule_size, image_binary_size; void *image_binary, *vendor_code; efi_handle_t *handles; efi_uintn_t no_handles; @@ -410,13 +437,30 @@ static efi_status_t efi_capsule_update_firmware( }
/* do update */ + if (IS_ENABLED(CONFIG_EFI_CAPSULE_AUTHENTICATE) && + !(image->image_capsule_support & + CAPSULE_SUPPORT_AUTHENTICATION)) { + /* no signature */ + ret = EFI_SECURITY_VIOLATION; + goto out; + } + image_binary = (void *)image + sizeof(*image); - vendor_code = image_binary + image->update_image_size; + image_binary_size = image->update_image_size; + vendor_code = image_binary + image_binary_size; + if (!IS_ENABLED(CONFIG_EFI_CAPSULE_AUTHENTICATE) && + (image->image_capsule_support & + CAPSULE_SUPPORT_AUTHENTICATION)) { + ret = efi_remove_auth_hdr(&image_binary, + &image_binary_size); + if (ret != EFI_SUCCESS) + goto out; + }
abort_reason = NULL; ret = EFI_CALL(fmp->set_image(fmp, image->update_image_index, image_binary, - image->update_image_size, + image_binary_size, vendor_code, NULL, &abort_reason)); if (ret != EFI_SUCCESS) {