From 0ebfada39e35d3366dfce45158a33f7624907d1f Mon Sep 17 00:00:00 2001 From: Gary Ching-Pang Lin Date: Fri, 21 Feb 2014 17:56:55 +0800 Subject: [PATCH] Add the option to revoke the built-in certificate This is an openSUSE-only patch. This commit adds an option to create ClearVerify which contains the password hash to notify MokManager to show the option to revoke the built-in certificate. --- src/mokutil.c | 82 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 82 insertions(+) diff --git a/src/mokutil.c b/src/mokutil.c index 1c32313..14adae7 100644 --- a/src/mokutil.c +++ b/src/mokutil.c @@ -83,6 +83,7 @@ EFI_GUID (0x605dab50, 0xe046, 0x4300, 0xab, 0xb6, 0x3d, 0xd8, 0x10, 0xdd, 0x8b, #define IMPORT_HASH (1 << 21) #define DELETE_HASH (1 << 22) #define VERBOSITY (1 << 23) +#define REVOKE_CERT (1 << 24) #define DEFAULT_CRYPT_METHOD SHA512_BASED #define DEFAULT_SALT_SIZE SHA512_SALT_MAX @@ -151,6 +152,7 @@ print_help () printf (" --kek\t\t\t\t\tList the keys in KEK\n"); printf (" --db\t\t\t\t\tList the keys in db\n"); printf (" --dbx\t\t\t\t\tList the keys in dbx\n"); + printf (" --revoke-cert\t\t\t\tRevoke the built-in certificate in shim\n"); printf ("\n"); printf ("Supplimentary Options:\n"); printf (" --hash-file \t\tUse the specific password hash\n"); @@ -1903,6 +1905,79 @@ set_verbosity (uint8_t verbosity) return 0; } +static int +revoke_builtin_cert (void) +{ + efi_variable_t var; + pw_crypt_t pw_crypt; + uint8_t auth[SHA256_DIGEST_LENGTH]; + char *password = NULL; + int pw_len; + int auth_ret; + int ret = -1; + + /* Check use_openSUSE_cert */ + memset (&var, 0, sizeof(var)); + var.VariableName = "use_openSUSE_cert"; + var.VendorGuid = SHIM_LOCK_GUID; + + if (read_variable (&var) != EFI_SUCCESS) + return 0; + + if ((uint8_t)*var.Data != 1) { + free (var.Data); + fprintf (stderr, "The built-in certificate is already revoked.\n"); + return 0; + } + free (var.Data); + + memset (&pw_crypt, 0, sizeof(pw_crypt_t)); + memset (auth, 0, SHA256_DIGEST_LENGTH); + + if (get_password (&password, &pw_len, PASSWORD_MIN, PASSWORD_MAX) < 0) { + fprintf (stderr, "Abort\n"); + goto error; + } + + if (!use_simple_hash) { + pw_crypt.method = DEFAULT_CRYPT_METHOD; + auth_ret = generate_hash (&pw_crypt, password, pw_len); + } else { + auth_ret = generate_auth (NULL, 0, password, pw_len, + auth); + } + if (auth_ret < 0) { + fprintf (stderr, "Couldn't generate hash\n"); + goto error; + } + + if (!use_simple_hash) { + var.Data = (void *)&pw_crypt; + var.DataSize = PASSWORD_CRYPT_SIZE; + } else { + var.Data = (void *)auth; + var.DataSize = SHA256_DIGEST_LENGTH; + } + var.VariableName = "ClearVerify"; + + var.VendorGuid = SHIM_LOCK_GUID; + var.Attributes = EFI_VARIABLE_NON_VOLATILE + | EFI_VARIABLE_BOOTSERVICE_ACCESS + | EFI_VARIABLE_RUNTIME_ACCESS; + + if (edit_protected_variable (&var) != EFI_SUCCESS) { + fprintf (stderr, "Failed to write ClearVerify\n"); + goto error; + } + + ret = 0; +error: + if (password) + free (password); + + return ret; +} + static inline int list_db (DBName db_name) { @@ -1974,6 +2049,7 @@ main (int argc, char *argv[]) {"kek", no_argument, 0, 0 }, {"db", no_argument, 0, 0 }, {"dbx", no_argument, 0, 0 }, + {"revoke-cert", no_argument, 0, 0 }, {0, 0, 0, 0} }; @@ -2061,6 +2137,8 @@ main (int argc, char *argv[]) command |= LIST_ENROLLED; db_name = DBX; } + } else if (strcmp (option, "revoke-cert") == 0) { + command |= REVOKE_CERT; } break; @@ -2303,6 +2381,10 @@ main (int argc, char *argv[]) case VERBOSITY: ret = set_verbosity (verbosity); break; + case REVOKE_CERT: + case REVOKE_CERT | SIMPLE_HASH: + ret = revoke_builtin_cert (); + break; default: print_help (); break; -- 1.8.4.5