projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| e0751257 DK |
1 | /* |
| 2 | * Copyright (C) 2013 Intel Corporation | |
| 3 | * | |
| 4 | * Author: | |
| 5 | * Dmitry Kasatkin <dmitry.kasatkin@intel.com> | |
| 6 | * | |
| 7 | * This program is free software; you can redistribute it and/or modify | |
| 8 | * it under the terms of the GNU General Public License as published by | |
| 9 | * the Free Software Foundation, version 2 of the License. | |
| 10 | * | |
| 11 | */ | |
| 12 | ||
| 13 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt | |
| 14 | ||
| 15 | #include <linux/err.h> | |
| d9a2e5d7 | 16 | #include <linux/ratelimit.h> |
| e0751257 DK |
17 | #include <linux/key-type.h> |
| 18 | #include <crypto/public_key.h> | |
| 19 | #include <keys/asymmetric-type.h> | |
| 41c89b64 | 20 | #include <keys/system_keyring.h> |
| e0751257 DK |
21 | |
| 22 | #include "integrity.h" | |
| 23 | ||
| e0751257 DK |
24 | /* |
| 25 | * Request an asymmetric key. | |
| 26 | */ | |
| 27 | static struct key *request_asymmetric_key(struct key *keyring, uint32_t keyid) | |
| 28 | { | |
| 29 | struct key *key; | |
| 30 | char name[12]; | |
| 31 | ||
| 594081ee | 32 | sprintf(name, "id:%08x", keyid); |
| e0751257 DK |
33 | |
| 34 | pr_debug("key search: \"%s\"\n", name); | |
| 35 | ||
| 41c89b64 PM |
36 | key = get_ima_blacklist_keyring(); |
| 37 | if (key) { | |
| 38 | key_ref_t kref; | |
| 39 | ||
| 40 | kref = keyring_search(make_key_ref(key, 1), | |
| 41 | &key_type_asymmetric, name); | |
| 42 | if (!IS_ERR(kref)) { | |
| 43 | pr_err("Key '%s' is in ima_blacklist_keyring\n", name); | |
| 44 | return ERR_PTR(-EKEYREJECTED); | |
| 45 | } | |
| 46 | } | |
| 47 | ||
| e0751257 DK |
48 | if (keyring) { |
| 49 | /* search in specific keyring */ | |
| 50 | key_ref_t kref; | |
| 41c89b64 | 51 | |
| e0751257 DK |
52 | kref = keyring_search(make_key_ref(keyring, 1), |
| 53 | &key_type_asymmetric, name); | |
| 54 | if (IS_ERR(kref)) | |
| 55 | key = ERR_CAST(kref); | |
| 56 | else | |
| 57 | key = key_ref_to_ptr(kref); | |
| 58 | } else { | |
| 59 | key = request_key(&key_type_asymmetric, name, NULL); | |
| 60 | } | |
| 61 | ||
| 62 | if (IS_ERR(key)) { | |
| d9a2e5d7 DK |
63 | pr_err_ratelimited("Request for unknown key '%s' err %ld\n", |
| 64 | name, PTR_ERR(key)); | |
| e0751257 DK |
65 | switch (PTR_ERR(key)) { |
| 66 | /* Hide some search errors */ | |
| 67 | case -EACCES: | |
| 68 | case -ENOTDIR: | |
| 69 | case -EAGAIN: | |
| 70 | return ERR_PTR(-ENOKEY); | |
| 71 | default: | |
| 72 | return key; | |
| 73 | } | |
| 74 | } | |
| 75 | ||
| 76 | pr_debug("%s() = 0 [%x]\n", __func__, key_serial(key)); | |
| 77 | ||
| 78 | return key; | |
| 79 | } | |
| 80 | ||
| 81 | int asymmetric_verify(struct key *keyring, const char *sig, | |
| 82 | int siglen, const char *data, int datalen) | |
| 83 | { | |
| 84 | struct public_key_signature pks; | |
| 85 | struct signature_v2_hdr *hdr = (struct signature_v2_hdr *)sig; | |
| 86 | struct key *key; | |
| 87 | int ret = -ENOMEM; | |
| 88 | ||
| 89 | if (siglen <= sizeof(*hdr)) | |
| 90 | return -EBADMSG; | |
| 91 | ||
| 92 | siglen -= sizeof(*hdr); | |
| 93 | ||
| 94 | if (siglen != __be16_to_cpu(hdr->sig_size)) | |
| 95 | return -EBADMSG; | |
| 96 | ||
| 97 | if (hdr->hash_algo >= PKEY_HASH__LAST) | |
| 98 | return -ENOPKG; | |
| 99 | ||
| 100 | key = request_asymmetric_key(keyring, __be32_to_cpu(hdr->keyid)); | |
| 101 | if (IS_ERR(key)) | |
| 102 | return PTR_ERR(key); | |
| 103 | ||
| 104 | memset(&pks, 0, sizeof(pks)); | |
| 105 | ||
| 106 | pks.pkey_hash_algo = hdr->hash_algo; | |
| 107 | pks.digest = (u8 *)data; | |
| 108 | pks.digest_size = datalen; | |
| 109 | pks.nr_mpi = 1; | |
| 110 | pks.rsa.s = mpi_read_raw_data(hdr->sig, siglen); | |
| 111 | ||
| 112 | if (pks.rsa.s) | |
| 113 | ret = verify_signature(key, &pks); | |
| 114 | ||
| 115 | mpi_free(pks.rsa.s); | |
| 116 | key_put(key); | |
| 117 | pr_debug("%s() = %d\n", __func__, ret); | |
| 118 | return ret; | |
| 119 | } |