1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 * Public Key Signature Algorithm
4 *
5 * Copyright (c) 2023 Herbert Xu <herbert@gondor.apana.org.au>
6 */
7
8 #include <crypto/akcipher.h>
9 #include <crypto/internal/sig.h>
10 #include <linux/cryptouser.h>
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/scatterlist.h>
14 #include <linux/seq_file.h>
15 #include <linux/string.h>
16 #include <net/netlink.h>
17
18 #include "internal.h"
19
20 #define CRYPTO_ALG_TYPE_SIG_MASK 0x0000000e
21
22 static const struct crypto_type crypto_sig_type;
23
24 static int crypto_sig_init_tfm(struct crypto_tfm *tfm)
25 {
26 if (tfm->__crt_alg->cra_type != &crypto_sig_type)
27 return crypto_init_akcipher_ops_sig(tfm);
28
29 return 0;
30 }
31
32 static void __maybe_unused crypto_sig_show(struct seq_file *m,
33 struct crypto_alg *alg)
34 {
35 seq_puts(m, "type : sig\n");
36 }
37
38 static int __maybe_unused crypto_sig_report(struct sk_buff *skb,
39 struct crypto_alg *alg)
40 {
41 struct crypto_report_akcipher rsig = {};
42
43 strscpy(rsig.type, "sig", sizeof(rsig.type));
44
45 return nla_put(skb, CRYPTOCFGA_REPORT_AKCIPHER, sizeof(rsig), &rsig);
46 }
47
48 static const struct crypto_type crypto_sig_type = {
49 .extsize = crypto_alg_extsize,
50 .init_tfm = crypto_sig_init_tfm,
51 #ifdef CONFIG_PROC_FS
52 .show = crypto_sig_show,
53 #endif
54 #if IS_ENABLED(CONFIG_CRYPTO_USER)
55 .report = crypto_sig_report,
56 #endif
57 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
58 .maskset = CRYPTO_ALG_TYPE_SIG_MASK,
59 .type = CRYPTO_ALG_TYPE_SIG,
60 .tfmsize = offsetof(struct crypto_sig, base),
61 };
62
63 struct crypto_sig *crypto_alloc_sig(const char *alg_name, u32 type, u32 mask)
64 {
65 return crypto_alloc_tfm(alg_name, &crypto_sig_type, type, mask);
66 }
67 EXPORT_SYMBOL_GPL(crypto_alloc_sig);
68
69 int crypto_sig_maxsize(struct crypto_sig *tfm)
70 {
71 struct crypto_akcipher **ctx = crypto_sig_ctx(tfm);
72
73 return crypto_akcipher_maxsize(*ctx);
74 }
75 EXPORT_SYMBOL_GPL(crypto_sig_maxsize);
76
77 int crypto_sig_sign(struct crypto_sig *tfm,
78 const void *src, unsigned int slen,
79 void *dst, unsigned int dlen)
80 {
81 struct crypto_akcipher **ctx = crypto_sig_ctx(tfm);
82 struct crypto_akcipher_sync_data data = {
83 .tfm = *ctx,
84 .src = src,
85 .dst = dst,
86 .slen = slen,
87 .dlen = dlen,
88 };
89
90 return crypto_akcipher_sync_prep(&data) ?:
91 crypto_akcipher_sync_post(&data,
92 crypto_akcipher_sign(data.req));
93 }
94 EXPORT_SYMBOL_GPL(crypto_sig_sign);
95
96 int crypto_sig_verify(struct crypto_sig *tfm,
97 const void *src, unsigned int slen,
98 const void *digest, unsigned int dlen)
99 {
100 struct crypto_akcipher **ctx = crypto_sig_ctx(tfm);
101 struct crypto_akcipher_sync_data data = {
102 .tfm = *ctx,
103 .src = src,
104 .slen = slen,
105 .dlen = dlen,
106 };
107 int err;
108
109 err = crypto_akcipher_sync_prep(&data);
110 if (err)
111 return err;
112
113 memcpy(data.buf + slen, digest, dlen);
114
115 return crypto_akcipher_sync_post(&data,
116 crypto_akcipher_verify(data.req));
117 }
118 EXPORT_SYMBOL_GPL(crypto_sig_verify);
119
120 int crypto_sig_set_pubkey(struct crypto_sig *tfm,
121 const void *key, unsigned int keylen)
122 {
123 struct crypto_akcipher **ctx = crypto_sig_ctx(tfm);
124
125 return crypto_akcipher_set_pub_key(*ctx, key, keylen);
126 }
127 EXPORT_SYMBOL_GPL(crypto_sig_set_pubkey);
128
129 int crypto_sig_set_privkey(struct crypto_sig *tfm,
130 const void *key, unsigned int keylen)
131 {
132 struct crypto_akcipher **ctx = crypto_sig_ctx(tfm);
133
134 return crypto_akcipher_set_priv_key(*ctx, key, keylen);
135 }
136 EXPORT_SYMBOL_GPL(crypto_sig_set_privkey);
137
138 MODULE_LICENSE("GPL");
139 MODULE_DESCRIPTION("Public Key Signature Algorithms");
140
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