Define a function which would be used in the scenario where the public key is stored on the platform's dtb. This dtb is concatenated with the u-boot binary during the build process. Platforms which have a different mechanism for getting the public key would define their own platform specific function under a different Kconfig symbol.
Signed-off-by: Sughosh Ganu sughosh.ganu@linaro.org ---
Changes since V1: * Remove the weak function, and add the functionality to retrieve the public key under the config symbol CONFIG_EFI_PKEY_DTB_EMBED.
lib/efi_loader/efi_capsule.c | 43 +++++++++++++++++++++++++++++++----- 1 file changed, 38 insertions(+), 5 deletions(-)
diff --git a/lib/efi_loader/efi_capsule.c b/lib/efi_loader/efi_capsule.c index 2cc8f2dee0..d95e9377fe 100644 --- a/lib/efi_loader/efi_capsule.c +++ b/lib/efi_loader/efi_capsule.c @@ -14,10 +14,13 @@ #include <mapmem.h> #include <sort.h>
+#include <asm/global_data.h> #include <crypto/pkcs7.h> #include <crypto/pkcs7_parser.h> #include <linux/err.h>
+DECLARE_GLOBAL_DATA_PTR; + const efi_guid_t efi_guid_capsule_report = EFI_CAPSULE_REPORT_GUID; static const efi_guid_t efi_guid_firmware_management_capsule_id = EFI_FIRMWARE_MANAGEMENT_CAPSULE_ID_GUID; @@ -208,15 +211,45 @@ skip: const efi_guid_t efi_guid_capsule_root_cert_guid = EFI_FIRMWARE_MANAGEMENT_CAPSULE_ID_GUID;
-__weak int efi_get_public_key_data(void **pkey, efi_uintn_t *pkey_len) +#if defined(CONFIG_EFI_PKEY_DTB_EMBED) +int efi_get_public_key_data(void **pkey, efi_uintn_t *pkey_len) { - /* The platform is supposed to provide - * a method for getting the public key - * stored in the form of efi signature - * list + /* + * This is a function for retrieving the public key from the + * platform's device tree. The platform's device tree has been + * concatenated with the u-boot binary. + * If a platform has a different mechanism to get the public + * key, it can define it's own kconfig symbol and define a + * function to retrieve the public key */ + const void *fdt_blob = gd->fdt_blob; + const void *blob; + const char *cnode_name = "capsule-key"; + const char *snode_name = "signature"; + int sig_node; + int len; + + sig_node = fdt_subnode_offset(fdt_blob, 0, snode_name); + if (sig_node < 0) { + EFI_PRINT("Unable to get signature node offset\n"); + return -FDT_ERR_NOTFOUND; + } + + blob = fdt_getprop(fdt_blob, sig_node, cnode_name, &len); + + if (!blob || len < 0) { + EFI_PRINT("Unable to get capsule-key value\n"); + *pkey = NULL; + *pkey_len = 0; + return -FDT_ERR_NOTFOUND; + } + + *pkey = (void *)blob; + *pkey_len = len; + return 0; } +#endif /* CONFIG_EFI_PKEY_DTB_EMBED */
efi_status_t efi_capsule_authenticate(const void *capsule, efi_uintn_t capsule_size, void **image, efi_uintn_t *image_size)