projects / linux-2.6-block.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> | |
| 20 | ||
| 21 | #include "integrity.h" | |
| 22 | ||
| e0751257 DK |
23 | /* |
| 24 | * Request an asymmetric key. | |
| 25 | */ | |
| 26 | static struct key *request_asymmetric_key(struct key *keyring, uint32_t keyid) | |
| 27 | { | |
| 28 | struct key *key; | |
| 29 | char name[12]; | |
| 30 | ||
| 594081ee | 31 | sprintf(name, "id:%08x", keyid); |
| e0751257 DK |
32 | |
| 33 | pr_debug("key search: \"%s\"\n", name); | |
| 34 | ||
| 35 | if (keyring) { | |
| 36 | /* search in specific keyring */ | |
| 37 | key_ref_t kref; | |
| 38 | kref = keyring_search(make_key_ref(keyring, 1), | |
| 39 | &key_type_asymmetric, name); | |
| 40 | if (IS_ERR(kref)) | |
| 41 | key = ERR_CAST(kref); | |
| 42 | else | |
| 43 | key = key_ref_to_ptr(kref); | |
| 44 | } else { | |
| 45 | key = request_key(&key_type_asymmetric, name, NULL); | |
| 46 | } | |
| 47 | ||
| 48 | if (IS_ERR(key)) { | |
| d9a2e5d7 DK |
49 | pr_err_ratelimited("Request for unknown key '%s' err %ld\n", |
| 50 | name, PTR_ERR(key)); | |
| e0751257 DK |
51 | switch (PTR_ERR(key)) { |
| 52 | /* Hide some search errors */ | |
| 53 | case -EACCES: | |
| 54 | case -ENOTDIR: | |
| 55 | case -EAGAIN: | |
| 56 | return ERR_PTR(-ENOKEY); | |
| 57 | default: | |
| 58 | return key; | |
| 59 | } | |
| 60 | } | |
| 61 | ||
| 62 | pr_debug("%s() = 0 [%x]\n", __func__, key_serial(key)); | |
| 63 | ||
| 64 | return key; | |
| 65 | } | |
| 66 | ||
| 67 | int asymmetric_verify(struct key *keyring, const char *sig, | |
| 68 | int siglen, const char *data, int datalen) | |
| 69 | { | |
| 70 | struct public_key_signature pks; | |
| 71 | struct signature_v2_hdr *hdr = (struct signature_v2_hdr *)sig; | |
| 72 | struct key *key; | |
| 73 | int ret = -ENOMEM; | |
| 74 | ||
| 75 | if (siglen <= sizeof(*hdr)) | |
| 76 | return -EBADMSG; | |
| 77 | ||
| 78 | siglen -= sizeof(*hdr); | |
| 79 | ||
| 80 | if (siglen != __be16_to_cpu(hdr->sig_size)) | |
| 81 | return -EBADMSG; | |
| 82 | ||
| 83 | if (hdr->hash_algo >= PKEY_HASH__LAST) | |
| 84 | return -ENOPKG; | |
| 85 | ||
| 86 | key = request_asymmetric_key(keyring, __be32_to_cpu(hdr->keyid)); | |
| 87 | if (IS_ERR(key)) | |
| 88 | return PTR_ERR(key); | |
| 89 | ||
| 90 | memset(&pks, 0, sizeof(pks)); | |
| 91 | ||
| 92 | pks.pkey_hash_algo = hdr->hash_algo; | |
| 93 | pks.digest = (u8 *)data; | |
| 94 | pks.digest_size = datalen; | |
| 95 | pks.nr_mpi = 1; | |
| 96 | pks.rsa.s = mpi_read_raw_data(hdr->sig, siglen); | |
| 97 | ||
| 98 | if (pks.rsa.s) | |
| 99 | ret = verify_signature(key, &pks); | |
| 100 | ||
| 101 | mpi_free(pks.rsa.s); | |
| 102 | key_put(key); | |
| 103 | pr_debug("%s() = %d\n", __func__, ret); | |
| 104 | return ret; | |
| 105 | } |