projects / mirror_ubuntu-artful-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 89052b26 JB |
1 | #include <linux/kernel.h> |
| 2 | #include <linux/sched.h> | |
| 3 | #include <linux/cred.h> | |
| 4 | #include <linux/err.h> | |
| 5 | #include <linux/efi.h> | |
| 6 | #include <linux/slab.h> | |
| 7 | #include <keys/asymmetric-type.h> | |
| 8 | #include <keys/system_keyring.h> | |
| 9 | #include "module-internal.h" | |
| 10 | ||
| d760d063 JB |
11 | static __init int check_ignore_db(void) |
| 12 | { | |
| 13 | efi_status_t status; | |
| 14 | unsigned int db = 0; | |
| 15 | unsigned long size = sizeof(db); | |
| 16 | efi_guid_t guid = EFI_SHIM_LOCK_GUID; | |
| 17 | ||
| 18 | /* Check and see if the MokIgnoreDB variable exists. If that fails | |
| 19 | * then we don't ignore DB. If it succeeds, we do. | |
| 20 | */ | |
| 21 | status = efi.get_variable(L"MokIgnoreDB", &guid, NULL, &size, &db); | |
| 22 | if (status != EFI_SUCCESS) | |
| 23 | return 0; | |
| 24 | ||
| 25 | return 1; | |
| 26 | } | |
| 27 | ||
| 89052b26 JB |
28 | static __init void *get_cert_list(efi_char16_t *name, efi_guid_t *guid, unsigned long *size) |
| 29 | { | |
| 30 | efi_status_t status; | |
| 31 | unsigned long lsize = 4; | |
| 32 | unsigned long tmpdb[4]; | |
| 33 | void *db = NULL; | |
| 34 | ||
| 35 | status = efi.get_variable(name, guid, NULL, &lsize, &tmpdb); | |
| 36 | if (status != EFI_BUFFER_TOO_SMALL) { | |
| 37 | pr_err("Couldn't get size: 0x%lx\n", status); | |
| 38 | return NULL; | |
| 39 | } | |
| 40 | ||
| 41 | db = kmalloc(lsize, GFP_KERNEL); | |
| 42 | if (!db) { | |
| 43 | pr_err("Couldn't allocate memory for uefi cert list\n"); | |
| 44 | goto out; | |
| 45 | } | |
| 46 | ||
| 47 | status = efi.get_variable(name, guid, NULL, &lsize, db); | |
| 48 | if (status != EFI_SUCCESS) { | |
| 49 | kfree(db); | |
| 50 | db = NULL; | |
| 51 | pr_err("Error reading db var: 0x%lx\n", status); | |
| 52 | } | |
| 53 | out: | |
| 54 | *size = lsize; | |
| 55 | return db; | |
| 56 | } | |
| 57 | ||
| 58 | /* | |
| 59 | * * Load the certs contained in the UEFI databases | |
| 60 | * */ | |
| 61 | static int __init load_uefi_certs(void) | |
| 62 | { | |
| 63 | efi_guid_t secure_var = EFI_IMAGE_SECURITY_DATABASE_GUID; | |
| 64 | efi_guid_t mok_var = EFI_SHIM_LOCK_GUID; | |
| 65 | void *db = NULL, *dbx = NULL, *mok = NULL; | |
| 66 | unsigned long dbsize = 0, dbxsize = 0, moksize = 0; | |
| d760d063 | 67 | int ignore_db, rc = 0; |
| 89052b26 JB |
68 | |
| 69 | /* Check if SB is enabled and just return if not */ | |
| 70 | if (!efi_enabled(EFI_SECURE_BOOT)) | |
| 71 | return 0; | |
| 72 | ||
| d760d063 JB |
73 | /* See if the user has setup Ignore DB mode */ |
| 74 | ignore_db = check_ignore_db(); | |
| 75 | ||
| 89052b26 JB |
76 | /* Get db, MokListRT, and dbx. They might not exist, so it isn't |
| 77 | * an error if we can't get them. | |
| 78 | */ | |
| d760d063 JB |
79 | if (!ignore_db) { |
| 80 | db = get_cert_list(L"db", &secure_var, &dbsize); | |
| 81 | if (!db) { | |
| 82 | pr_err("MODSIGN: Couldn't get UEFI db list\n"); | |
| 83 | } else { | |
| 84 | rc = parse_efi_signature_list(db, dbsize, system_trusted_keyring); | |
| 85 | if (rc) | |
| 86 | pr_err("Couldn't parse db signatures: %d\n", rc); | |
| 87 | kfree(db); | |
| 88 | } | |
| 89052b26 JB |
89 | } |
| 90 | ||
| 91 | mok = get_cert_list(L"MokListRT", &mok_var, &moksize); | |
| 92 | if (!mok) { | |
| 93 | pr_info("MODSIGN: Couldn't get UEFI MokListRT\n"); | |
| 94 | } else { | |
| 95 | rc = parse_efi_signature_list(mok, moksize, system_trusted_keyring); | |
| 96 | if (rc) | |
| 97 | pr_err("Couldn't parse MokListRT signatures: %d\n", rc); | |
| 98 | kfree(mok); | |
| 99 | } | |
| 100 | ||
| 101 | dbx = get_cert_list(L"dbx", &secure_var, &dbxsize); | |
| 102 | if (!dbx) { | |
| 103 | pr_info("MODSIGN: Couldn't get UEFI dbx list\n"); | |
| 104 | } else { | |
| 105 | rc = parse_efi_signature_list(dbx, dbxsize, | |
| 106 | system_blacklist_keyring); | |
| 107 | if (rc) | |
| 108 | pr_err("Couldn't parse dbx signatures: %d\n", rc); | |
| 109 | kfree(dbx); | |
| 110 | } | |
| 111 | ||
| 112 | return rc; | |
| 113 | } | |
| 114 | late_initcall(load_uefi_certs); |