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https://github.com/brain-hackers/u-boot-brain
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efi_loader: add signature verification functions
In this commit, implemented are a couple of helper functions which will be used to materialize variable authentication as well as image authentication in later patches. Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
This commit is contained in:
AKASHI Takahiro
Heinrich Schuchardt
parent
9bf09b5120
commit
593e17d673
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@ -18,6 +18,7 @@
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#include <efi.h>
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#include <charset.h>
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#include <pe.h>
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#ifdef CONFIG_EFI_LOADER
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#include <asm/setjmp.h>
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@ -329,6 +330,10 @@ struct efi_runtime_services {
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EFI_GUID(0x8be4df61, 0x93ca, 0x11d2, 0xaa, 0x0d, \
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0x00, 0xe0, 0x98, 0x03, 0x2b, 0x8c)
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#define EFI_IMAGE_SECURITY_DATABASE_GUID \
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EFI_GUID(0xd719b2cb, 0x3d3a, 0x4596, 0xa3, 0xbc, \
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0xda, 0xd0, 0x0e, 0x67, 0x65, 0x6f)
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#define EFI_FDT_GUID \
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EFI_GUID(0xb1b621d5, 0xf19c, 0x41a5, \
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0x83, 0x0b, 0xd9, 0x15, 0x2c, 0x69, 0xaa, 0xe0)
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@ -1682,4 +1687,86 @@ struct efi_load_file_protocol {
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#define LAST_ATTEMPT_STATUS_ERROR_UNSUCCESSFUL_VENDOR_RANGE_MIN 0x00001000
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#define LAST_ATTEMPT_STATUS_ERROR_UNSUCCESSFUL_VENDOR_RANGE_MAX 0x00004000
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/* Certificate types in signature database */
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#define EFI_CERT_SHA256_GUID \
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EFI_GUID(0xc1c41626, 0x504c, 0x4092, 0xac, 0xa9, \
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0x41, 0xf9, 0x36, 0x93, 0x43, 0x28)
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#define EFI_CERT_RSA2048_GUID \
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EFI_GUID(0x3c5766e8, 0x269c, 0x4e34, 0xaa, 0x14, \
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0xed, 0x77, 0x6e, 0x85, 0xb3, 0xb6)
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#define EFI_CERT_X509_GUID \
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EFI_GUID(0xa5c059a1, 0x94e4, 0x4aa7, 0x87, 0xb5, \
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0xab, 0x15, 0x5c, 0x2b, 0xf0, 0x72)
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#define EFI_CERT_X509_SHA256_GUID \
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EFI_GUID(0x3bd2a492, 0x96c0, 0x4079, 0xb4, 0x20, \
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0xfc, 0xf9, 0x8e, 0xf1, 0x03, 0xed)
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#define EFI_CERT_TYPE_PKCS7_GUID \
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EFI_GUID(0x4aafd29d, 0x68df, 0x49ee, 0x8a, 0xa9, \
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0x34, 0x7d, 0x37, 0x56, 0x65, 0xa7)
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/**
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* win_certificate_uefi_guid - A certificate that encapsulates
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* a GUID-specific signature
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*
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* @hdr: Windows certificate header
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* @cert_type: Certificate type
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* @cert_data: Certificate data
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*/
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struct win_certificate_uefi_guid {
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WIN_CERTIFICATE hdr;
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efi_guid_t cert_type;
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u8 cert_data[];
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} __attribute__((__packed__));
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/**
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* efi_variable_authentication_2 - A time-based authentication method
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* descriptor
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*
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* This structure describes an authentication information for
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* a variable with EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS
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* and should be included as part of a variable's value.
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* Only EFI_CERT_TYPE_PKCS7_GUID is accepted.
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*
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* @time_stamp: Descriptor's time stamp
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* @auth_info: Authentication info
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*/
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struct efi_variable_authentication_2 {
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struct efi_time time_stamp;
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struct win_certificate_uefi_guid auth_info;
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} __attribute__((__packed__));
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/**
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* efi_signature_data - A format of signature
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*
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* This structure describes a single signature in signature database.
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*
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* @signature_owner: Signature owner
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* @signature_data: Signature data
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*/
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struct efi_signature_data {
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efi_guid_t signature_owner;
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u8 signature_data[];
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} __attribute__((__packed__));
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/**
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* efi_signature_list - A format of signature database
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*
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* This structure describes a list of signatures with the same type.
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* An authenticated variable's value is a concatenation of one or more
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* efi_signature_list's.
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*
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* @signature_type: Signature type
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* @signature_list_size: Size of signature list
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* @signature_header_size: Size of signature header
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* @signature_size: Size of signature
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*/
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struct efi_signature_list {
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efi_guid_t signature_type;
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u32 signature_list_size;
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u32 signature_header_size;
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u32 signature_size;
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/* u8 signature_header[signature_header_size]; */
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/* struct efi_signature_data signatures[...][signature_size]; */
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} __attribute__((__packed__));
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#endif
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@ -26,6 +26,7 @@ static inline void *guidcpy(void *dst, const void *src)
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#if CONFIG_IS_ENABLED(EFI_LOADER)
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#include <linux/list.h>
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#include <linux/oid_registry.h>
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/* Maximum number of configuration tables */
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#define EFI_MAX_CONFIGURATION_TABLES 16
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@ -178,6 +179,11 @@ extern const efi_guid_t efi_guid_hii_config_routing_protocol;
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extern const efi_guid_t efi_guid_hii_config_access_protocol;
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extern const efi_guid_t efi_guid_hii_database_protocol;
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extern const efi_guid_t efi_guid_hii_string_protocol;
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/* GUIDs for authentication */
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extern const efi_guid_t efi_guid_image_security_database;
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extern const efi_guid_t efi_guid_sha256;
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extern const efi_guid_t efi_guid_cert_x509;
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extern const efi_guid_t efi_guid_cert_x509_sha256;
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/* GUID of RNG protocol */
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extern const efi_guid_t efi_guid_rng_protocol;
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@ -680,6 +686,72 @@ void efi_deserialize_load_option(struct efi_load_option *lo, u8 *data);
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unsigned long efi_serialize_load_option(struct efi_load_option *lo, u8 **data);
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efi_status_t efi_bootmgr_load(efi_handle_t *handle);
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#ifdef CONFIG_EFI_SECURE_BOOT
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#include <image.h>
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/**
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* efi_image_regions - A list of memory regions
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*
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* @max: Maximum number of regions
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* @num: Number of regions
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* @reg: array of regions
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*/
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struct efi_image_regions {
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int max;
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int num;
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struct image_region reg[];
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};
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/**
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* efi_sig_data - A decoded data of struct efi_signature_data
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*
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* This structure represents an internal form of signature in
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* signature database. A listed list may represent a signature list.
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*
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* @next: Pointer to next entry
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* @onwer: Signature owner
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* @data: Pointer to signature data
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* @size: Size of signature data
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*/
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struct efi_sig_data {
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struct efi_sig_data *next;
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efi_guid_t owner;
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void *data;
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size_t size;
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};
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/**
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* efi_signature_store - A decoded data of signature database
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*
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* This structure represents an internal form of signature database.
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*
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* @next: Pointer to next entry
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* @sig_type: Signature type
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* @sig_data_list: Pointer to signature list
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*/
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struct efi_signature_store {
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struct efi_signature_store *next;
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efi_guid_t sig_type;
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struct efi_sig_data *sig_data_list;
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};
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struct x509_certificate;
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struct pkcs7_message;
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bool efi_signature_verify_cert(struct x509_certificate *cert,
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struct efi_signature_store *dbx);
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bool efi_signature_verify_signers(struct pkcs7_message *msg,
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struct efi_signature_store *dbx);
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bool efi_signature_verify_with_sigdb(struct efi_image_regions *regs,
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struct pkcs7_message *msg,
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struct efi_signature_store *db,
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struct x509_certificate **cert);
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efi_status_t efi_image_region_add(struct efi_image_regions *regs,
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const void *start, const void *end,
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int nocheck);
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#endif /* CONFIG_EFI_SECURE_BOOT */
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#else /* CONFIG_IS_ENABLED(EFI_LOADER) */
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/* Without CONFIG_EFI_LOADER we don't have a runtime section, stub it out */
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@ -44,3 +44,4 @@ obj-$(CONFIG_GENERATE_ACPI_TABLE) += efi_acpi.o
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obj-$(CONFIG_GENERATE_SMBIOS_TABLE) += efi_smbios.o
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obj-$(CONFIG_EFI_RNG_PROTOCOL) += efi_rng.o
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obj-$(CONFIG_EFI_LOAD_FILE2_INITRD) += efi_load_initrd.o
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obj-y += efi_signature.o
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578
lib/efi_loader/efi_signature.c
Normal file
578
lib/efi_loader/efi_signature.c
Normal file
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@ -0,0 +1,578 @@
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// SPDX-License-Identifier: GPL-2.0+
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/*
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* Copyright (c) 2018 Patrick Wildt <patrick@blueri.se>
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* Copyright (c) 2019 Linaro Limited, Author: AKASHI Takahiro
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*/
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#include <common.h>
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#include <charset.h>
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#include <efi_loader.h>
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#include <image.h>
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#include <hexdump.h>
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#include <malloc.h>
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#include <linux/compat.h>
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#include <linux/oid_registry.h>
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#include <u-boot/rsa.h>
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#include <u-boot/sha256.h>
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#include "../lib/crypto/pkcs7_parser.h"
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const efi_guid_t efi_guid_image_security_database =
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EFI_IMAGE_SECURITY_DATABASE_GUID;
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const efi_guid_t efi_guid_sha256 = EFI_CERT_SHA256_GUID;
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const efi_guid_t efi_guid_cert_rsa2048 = EFI_CERT_RSA2048_GUID;
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const efi_guid_t efi_guid_cert_x509 = EFI_CERT_X509_GUID;
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const efi_guid_t efi_guid_cert_x509_sha256 = EFI_CERT_X509_SHA256_GUID;
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#ifdef CONFIG_EFI_SECURE_BOOT
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/**
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* efi_hash_regions - calculate a hash value
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* @regs: List of regions
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* @hash: Pointer to a pointer to buffer holding a hash value
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* @size: Size of buffer to be returned
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*
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* Calculate a sha256 value of @regs and return a value in @hash.
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*
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* Return: true on success, false on error
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*/
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static bool efi_hash_regions(struct efi_image_regions *regs, void **hash,
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size_t *size)
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{
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*size = 0;
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*hash = calloc(1, SHA256_SUM_LEN);
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if (!*hash) {
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debug("Out of memory\n");
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return false;
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}
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*size = SHA256_SUM_LEN;
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hash_calculate("sha256", regs->reg, regs->num, *hash);
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#ifdef DEBUG
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debug("hash calculated:\n");
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print_hex_dump(" ", DUMP_PREFIX_OFFSET, 16, 1,
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*hash, SHA256_SUM_LEN, false);
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#endif
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return true;
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}
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/**
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* efi_hash_msg_content - calculate a hash value of contentInfo
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* @msg: Signature
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* @hash: Pointer to a pointer to buffer holding a hash value
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* @size: Size of buffer to be returned
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*
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* Calculate a sha256 value of contentInfo in @msg and return a value in @hash.
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*
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* Return: true on success, false on error
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*/
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static bool efi_hash_msg_content(struct pkcs7_message *msg, void **hash,
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size_t *size)
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{
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struct image_region regtmp;
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*size = 0;
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*hash = calloc(1, SHA256_SUM_LEN);
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if (!*hash) {
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debug("Out of memory\n");
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free(msg);
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return false;
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}
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*size = SHA256_SUM_LEN;
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regtmp.data = msg->data;
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regtmp.size = msg->data_len;
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hash_calculate("sha256", ®tmp, 1, *hash);
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#ifdef DEBUG
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debug("hash calculated based on contentInfo:\n");
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print_hex_dump(" ", DUMP_PREFIX_OFFSET, 16, 1,
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*hash, SHA256_SUM_LEN, false);
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#endif
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return true;
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}
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/**
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* efi_signature_verify - verify a signature with a certificate
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* @regs: List of regions to be authenticated
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* @signed_info: Pointer to PKCS7's signed_info
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* @cert: x509 certificate
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*
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* Signature pointed to by @signed_info against image pointed to by @regs
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* is verified by a certificate pointed to by @cert.
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* @signed_info holds a signature, including a message digest which is to be
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* compared with a hash value calculated from @regs.
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*
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* Return: true if signature is verified, false if not
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*/
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static bool efi_signature_verify(struct efi_image_regions *regs,
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struct pkcs7_message *msg,
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struct pkcs7_signed_info *ps_info,
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struct x509_certificate *cert)
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{
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struct image_sign_info info;
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struct image_region regtmp[2];
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void *hash;
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size_t size;
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char c;
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bool verified;
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debug("%s: Enter, %p, %p, %p(issuer: %s, subject: %s)\n", __func__,
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regs, ps_info, cert, cert->issuer, cert->subject);
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verified = false;
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memset(&info, '\0', sizeof(info));
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info.padding = image_get_padding_algo("pkcs-1.5");
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/*
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* Note: image_get_[checksum|crypto]_algo takes an string
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* argument like "<checksum>,<crypto>"
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* TODO: support other hash algorithms
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*/
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if (!strcmp(ps_info->sig->hash_algo, "sha1")) {
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info.checksum = image_get_checksum_algo("sha1,rsa2048");
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info.name = "sha1,rsa2048";
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} else if (!strcmp(ps_info->sig->hash_algo, "sha256")) {
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info.checksum = image_get_checksum_algo("sha256,rsa2048");
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info.name = "sha256,rsa2048";
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} else {
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debug("unknown msg digest algo: %s\n", ps_info->sig->hash_algo);
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goto out;
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}
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info.crypto = image_get_crypto_algo(info.name);
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info.key = cert->pub->key;
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info.keylen = cert->pub->keylen;
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/* verify signature */
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debug("%s: crypto: %s, signature len:%x\n", __func__,
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info.name, ps_info->sig->s_size);
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if (ps_info->aa_set & (1UL << sinfo_has_message_digest)) {
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debug("%s: RSA verify authentication attribute\n", __func__);
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/*
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* NOTE: This path will be executed only for
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* PE image authentication
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*/
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/* check if hash matches digest first */
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debug("checking msg digest first, len:0x%x\n",
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ps_info->msgdigest_len);
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#ifdef DEBUG
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debug("hash in database:\n");
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print_hex_dump(" ", DUMP_PREFIX_OFFSET, 16, 1,
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ps_info->msgdigest, ps_info->msgdigest_len,
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false);
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#endif
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/* against contentInfo first */
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if ((msg->data && efi_hash_msg_content(msg, &hash, &size)) ||
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/* for signed image */
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efi_hash_regions(regs, &hash, &size)) {
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/* for authenticated variable */
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if (ps_info->msgdigest_len != size ||
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memcmp(hash, ps_info->msgdigest, size)) {
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debug("Digest doesn't match\n");
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free(hash);
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goto out;
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}
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free(hash);
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} else {
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debug("Digesting image failed\n");
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goto out;
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}
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/* against digest */
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c = 0x31;
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regtmp[0].data = &c;
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regtmp[0].size = 1;
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regtmp[1].data = ps_info->authattrs;
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regtmp[1].size = ps_info->authattrs_len;
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if (!rsa_verify(&info, regtmp, 2,
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ps_info->sig->s, ps_info->sig->s_size))
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verified = true;
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} else {
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debug("%s: RSA verify content data\n", __func__);
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/* against all data */
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if (!rsa_verify(&info, regs->reg, regs->num,
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ps_info->sig->s, ps_info->sig->s_size))
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verified = true;
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}
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out:
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debug("%s: Exit, verified: %d\n", __func__, verified);
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return verified;
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}
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/**
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* efi_signature_verify_with_list - verify a signature with signature list
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* @regs: List of regions to be authenticated
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* @msg: Signature
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* @signed_info: Pointer to PKCS7's signed_info
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* @siglist: Signature list for certificates
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* @valid_cert: x509 certificate that verifies this signature
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*
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* Signature pointed to by @signed_info against image pointed to by @regs
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* is verified by signature list pointed to by @siglist.
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* Signature database is a simple concatenation of one or more
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||||
* signature list(s).
|
||||
*
|
||||
* Return: true if signature is verified, false if not
|
||||
*/
|
||||
static
|
||||
bool efi_signature_verify_with_list(struct efi_image_regions *regs,
|
||||
struct pkcs7_message *msg,
|
||||
struct pkcs7_signed_info *signed_info,
|
||||
struct efi_signature_store *siglist,
|
||||
struct x509_certificate **valid_cert)
|
||||
{
|
||||
struct x509_certificate *cert;
|
||||
struct efi_sig_data *sig_data;
|
||||
bool verified = false;
|
||||
|
||||
debug("%s: Enter, %p, %p, %p, %p\n", __func__,
|
||||
regs, signed_info, siglist, valid_cert);
|
||||
|
||||
if (!signed_info) {
|
||||
void *hash;
|
||||
size_t size;
|
||||
|
||||
debug("%s: unsigned image\n", __func__);
|
||||
/*
|
||||
* verify based on calculated hash value
|
||||
* TODO: support other hash algorithms
|
||||
*/
|
||||
if (guidcmp(&siglist->sig_type, &efi_guid_sha256)) {
|
||||
debug("Digest algorithm is not supported: %pUl\n",
|
||||
&siglist->sig_type);
|
||||
goto out;
|
||||
}
|
||||
|
||||
if (!efi_hash_regions(regs, &hash, &size)) {
|
||||
debug("Digesting unsigned image failed\n");
|
||||
goto out;
|
||||
}
|
||||
|
||||
/* go through the list */
|
||||
for (sig_data = siglist->sig_data_list; sig_data;
|
||||
sig_data = sig_data->next) {
|
||||
#ifdef DEBUG
|
||||
debug("Msg digest in database:\n");
|
||||
print_hex_dump(" ", DUMP_PREFIX_OFFSET, 16, 1,
|
||||
sig_data->data, sig_data->size, false);
|
||||
#endif
|
||||
if ((sig_data->size == size) &&
|
||||
!memcmp(sig_data->data, hash, size)) {
|
||||
verified = true;
|
||||
free(hash);
|
||||
goto out;
|
||||
}
|
||||
}
|
||||
free(hash);
|
||||
goto out;
|
||||
}
|
||||
|
||||
debug("%s: signed image\n", __func__);
|
||||
if (guidcmp(&siglist->sig_type, &efi_guid_cert_x509)) {
|
||||
debug("Signature type is not supported: %pUl\n",
|
||||
&siglist->sig_type);
|
||||
goto out;
|
||||
}
|
||||
|
||||
/* go through the list */
|
||||
for (sig_data = siglist->sig_data_list; sig_data;
|
||||
sig_data = sig_data->next) {
|
||||
/* TODO: support owner check based on policy */
|
||||
|
||||
cert = x509_cert_parse(sig_data->data, sig_data->size);
|
||||
if (IS_ERR(cert)) {
|
||||
debug("Parsing x509 certificate failed\n");
|
||||
goto out;
|
||||
}
|
||||
|
||||
verified = efi_signature_verify(regs, msg, signed_info, cert);
|
||||
|
||||
if (verified) {
|
||||
if (valid_cert)
|
||||
*valid_cert = cert;
|
||||
else
|
||||
x509_free_certificate(cert);
|
||||
break;
|
||||
}
|
||||
x509_free_certificate(cert);
|
||||
}
|
||||
|
||||
out:
|
||||
debug("%s: Exit, verified: %d\n", __func__, verified);
|
||||
return verified;
|
||||
}
|
||||
|
||||
/**
|
||||
* efi_signature_verify_with_sigdb - verify a signature with db
|
||||
* @regs: List of regions to be authenticated
|
||||
* @msg: Signature
|
||||
* @db: Signature database for trusted certificates
|
||||
* @cert: x509 certificate that verifies this signature
|
||||
*
|
||||
* Signature pointed to by @msg against image pointed to by @regs
|
||||
* is verified by signature database pointed to by @db.
|
||||
*
|
||||
* Return: true if signature is verified, false if not
|
||||
*/
|
||||
bool efi_signature_verify_with_sigdb(struct efi_image_regions *regs,
|
||||
struct pkcs7_message *msg,
|
||||
struct efi_signature_store *db,
|
||||
struct x509_certificate **cert)
|
||||
{
|
||||
struct pkcs7_signed_info *info;
|
||||
struct efi_signature_store *siglist;
|
||||
bool verified = false;
|
||||
|
||||
debug("%s: Enter, %p, %p, %p, %p\n", __func__, regs, msg, db, cert);
|
||||
|
||||
if (!db)
|
||||
goto out;
|
||||
|
||||
if (!db->sig_data_list)
|
||||
goto out;
|
||||
|
||||
/* for unsigned image */
|
||||
if (!msg) {
|
||||
debug("%s: Verify unsigned image with db\n", __func__);
|
||||
for (siglist = db; siglist; siglist = siglist->next)
|
||||
if (efi_signature_verify_with_list(regs, NULL, NULL,
|
||||
siglist, cert)) {
|
||||
verified = true;
|
||||
goto out;
|
||||
}
|
||||
|
||||
goto out;
|
||||
}
|
||||
|
||||
/* for signed image or variable */
|
||||
debug("%s: Verify signed image with db\n", __func__);
|
||||
for (info = msg->signed_infos; info; info = info->next) {
|
||||
debug("Signed Info: digest algo: %s, pkey algo: %s\n",
|
||||
info->sig->hash_algo, info->sig->pkey_algo);
|
||||
|
||||
for (siglist = db; siglist; siglist = siglist->next) {
|
||||
if (efi_signature_verify_with_list(regs, msg, info,
|
||||
siglist, cert)) {
|
||||
verified = true;
|
||||
goto out;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
out:
|
||||
debug("%s: Exit, verified: %d\n", __func__, verified);
|
||||
return verified;
|
||||
}
|
||||
|
||||
/**
|
||||
* efi_search_siglist - search signature list for a certificate
|
||||
* @cert: x509 certificate
|
||||
* @siglist: Signature list
|
||||
* @revoc_time: Pointer to buffer for revocation time
|
||||
*
|
||||
* Search signature list pointed to by @siglist and find a certificate
|
||||
* pointed to by @cert.
|
||||
* If found, revocation time that is specified in signature database is
|
||||
* returned in @revoc_time.
|
||||
*
|
||||
* Return: true if certificate is found, false if not
|
||||
*/
|
||||
static bool efi_search_siglist(struct x509_certificate *cert,
|
||||
struct efi_signature_store *siglist,
|
||||
time64_t *revoc_time)
|
||||
{
|
||||
struct image_region reg[1];
|
||||
void *hash = NULL, *msg = NULL;
|
||||
struct efi_sig_data *sig_data;
|
||||
bool found = false;
|
||||
|
||||
/* can be null */
|
||||
if (!siglist->sig_data_list)
|
||||
return false;
|
||||
|
||||
if (guidcmp(&siglist->sig_type, &efi_guid_cert_x509_sha256)) {
|
||||
/* TODO: other hash algos */
|
||||
debug("Certificate's digest type is not supported: %pUl\n",
|
||||
&siglist->sig_type);
|
||||
goto out;
|
||||
}
|
||||
|
||||
/* calculate hash of TBSCertificate */
|
||||
msg = calloc(1, SHA256_SUM_LEN);
|
||||
if (!msg) {
|
||||
debug("Out of memory\n");
|
||||
goto out;
|
||||
}
|
||||
|
||||
hash = calloc(1, SHA256_SUM_LEN);
|
||||
if (!hash) {
|
||||
debug("Out of memory\n");
|
||||
goto out;
|
||||
}
|
||||
|
||||
reg[0].data = cert->tbs;
|
||||
reg[0].size = cert->tbs_size;
|
||||
hash_calculate("sha256", reg, 1, msg);
|
||||
|
||||
/* go through signature list */
|
||||
for (sig_data = siglist->sig_data_list; sig_data;
|
||||
sig_data = sig_data->next) {
|
||||
/*
|
||||
* struct efi_cert_x509_sha256 {
|
||||
* u8 tbs_hash[256/8];
|
||||
* time64_t revocation_time;
|
||||
* };
|
||||
*/
|
||||
if ((sig_data->size == SHA256_SUM_LEN) &&
|
||||
!memcmp(sig_data->data, hash, SHA256_SUM_LEN)) {
|
||||
memcpy(revoc_time, sig_data->data + SHA256_SUM_LEN,
|
||||
sizeof(*revoc_time));
|
||||
found = true;
|
||||
goto out;
|
||||
}
|
||||
}
|
||||
|
||||
out:
|
||||
free(hash);
|
||||
free(msg);
|
||||
|
||||
return found;
|
||||
}
|
||||
|
||||
/**
|
||||
* efi_signature_verify_cert - verify a certificate with dbx
|
||||
* @cert: x509 certificate
|
||||
* @dbx: Signature database
|
||||
*
|
||||
* Search signature database pointed to by @dbx and find a certificate
|
||||
* pointed to by @cert.
|
||||
* This function is expected to be used against "dbx".
|
||||
*
|
||||
* Return: true if a certificate is not rejected, false otherwise.
|
||||
*/
|
||||
bool efi_signature_verify_cert(struct x509_certificate *cert,
|
||||
struct efi_signature_store *dbx)
|
||||
{
|
||||
struct efi_signature_store *siglist;
|
||||
time64_t revoc_time;
|
||||
bool found = false;
|
||||
|
||||
debug("%s: Enter, %p, %p\n", __func__, dbx, cert);
|
||||
|
||||
if (!cert)
|
||||
return false;
|
||||
|
||||
for (siglist = dbx; siglist; siglist = siglist->next) {
|
||||
if (efi_search_siglist(cert, siglist, &revoc_time)) {
|
||||
/* TODO */
|
||||
/* compare signing time with revocation time */
|
||||
|
||||
found = true;
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
debug("%s: Exit, verified: %d\n", __func__, !found);
|
||||
return !found;
|
||||
}
|
||||
|
||||
/**
|
||||
* efi_signature_verify_signers - verify signers' certificates with dbx
|
||||
* @msg: Signature
|
||||
* @dbx: Signature database
|
||||
*
|
||||
* Determine if any of signers' certificates in @msg may be verified
|
||||
* by any of certificates in signature database pointed to by @dbx.
|
||||
* This function is expected to be used against "dbx".
|
||||
*
|
||||
* Return: true if none of certificates is rejected, false otherwise.
|
||||
*/
|
||||
bool efi_signature_verify_signers(struct pkcs7_message *msg,
|
||||
struct efi_signature_store *dbx)
|
||||
{
|
||||
struct pkcs7_signed_info *info;
|
||||
bool found = false;
|
||||
|
||||
debug("%s: Enter, %p, %p\n", __func__, msg, dbx);
|
||||
|
||||
if (!msg)
|
||||
goto out;
|
||||
|
||||
for (info = msg->signed_infos; info; info = info->next) {
|
||||
if (info->signer &&
|
||||
!efi_signature_verify_cert(info->signer, dbx)) {
|
||||
found = true;
|
||||
goto out;
|
||||
}
|
||||
}
|
||||
out:
|
||||
debug("%s: Exit, verified: %d\n", __func__, !found);
|
||||
return !found;
|
||||
}
|
||||
|
||||
/**
|
||||
* efi_image_region_add - add an entry of region
|
||||
* @regs: Pointer to array of regions
|
||||
* @start: Start address of region
|
||||
* @end: End address of region
|
||||
* @nocheck: flag against overlapped regions
|
||||
*
|
||||
* Take one entry of region [@start, @end] and append it to the list
|
||||
* pointed to by @regs. If @nocheck is false, overlapping among entries
|
||||
* will be checked first.
|
||||
*
|
||||
* Return: 0 on success, status code (negative) on error
|
||||
*/
|
||||
efi_status_t efi_image_region_add(struct efi_image_regions *regs,
|
||||
const void *start, const void *end,
|
||||
int nocheck)
|
||||
{
|
||||
struct image_region *reg;
|
||||
int i, j;
|
||||
|
||||
if (regs->num >= regs->max) {
|
||||
debug("%s: no more room for regions\n", __func__);
|
||||
return EFI_OUT_OF_RESOURCES;
|
||||
}
|
||||
|
||||
if (end < start)
|
||||
return EFI_INVALID_PARAMETER;
|
||||
|
||||
for (i = 0; i < regs->num; i++) {
|
||||
reg = ®s->reg[i];
|
||||
if (nocheck)
|
||||
continue;
|
||||
|
||||
if (start > reg->data + reg->size)
|
||||
continue;
|
||||
|
||||
if ((start >= reg->data && start < reg->data + reg->size) ||
|
||||
(end > reg->data && end < reg->data + reg->size)) {
|
||||
debug("%s: new region already part of another\n",
|
||||
__func__);
|
||||
return EFI_INVALID_PARAMETER;
|
||||
}
|
||||
|
||||
if (start < reg->data && end < reg->data + reg->size) {
|
||||
for (j = regs->num - 1; j >= i; j--)
|
||||
memcpy(®s->reg[j], ®s->reg[j + 1],
|
||||
sizeof(*reg));
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
reg = ®s->reg[i];
|
||||
reg->data = start;
|
||||
reg->size = end - start;
|
||||
regs->num++;
|
||||
|
||||
return EFI_SUCCESS;
|
||||
}
|
||||
#endif /* CONFIG_EFI_SECURE_BOOT */
|
||||
Loading…
Reference in New Issue
Block a user