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/internal/sig.h>
9#include <linux/cryptouser.h>
10#include <linux/kernel.h>
11#include <linux/module.h>
12#include <linux/seq_file.h>
13#include <linux/string.h>
14#include <net/netlink.h>
15
16#include "internal.h"
17
18static void crypto_sig_exit_tfm(struct crypto_tfm *tfm)
19{
20 struct crypto_sig *sig = __crypto_sig_tfm(tfm);
21 struct sig_alg *alg = crypto_sig_alg(tfm: sig);
22
23 alg->exit(sig);
24}
25
26static int crypto_sig_init_tfm(struct crypto_tfm *tfm)
27{
28 struct crypto_sig *sig = __crypto_sig_tfm(tfm);
29 struct sig_alg *alg = crypto_sig_alg(tfm: sig);
30
31 if (alg->exit)
32 sig->base.exit = crypto_sig_exit_tfm;
33
34 if (alg->init)
35 return alg->init(sig);
36
37 return 0;
38}
39
40static void crypto_sig_free_instance(struct crypto_instance *inst)
41{
42 struct sig_instance *sig = sig_instance(inst);
43
44 sig->free(sig);
45}
46
47static void __maybe_unused crypto_sig_show(struct seq_file *m,
48 struct crypto_alg *alg)
49{
50 seq_puts(m, s: "type : sig\n");
51}
52
53static int __maybe_unused crypto_sig_report(struct sk_buff *skb,
54 struct crypto_alg *alg)
55{
56 struct crypto_report_sig rsig = {};
57
58 strscpy(rsig.type, "sig", sizeof(rsig.type));
59
60 return nla_put(skb, attrtype: CRYPTOCFGA_REPORT_SIG, attrlen: sizeof(rsig), data: &rsig);
61}
62
63static const struct crypto_type crypto_sig_type = {
64 .extsize = crypto_alg_extsize,
65 .init_tfm = crypto_sig_init_tfm,
66 .free = crypto_sig_free_instance,
67#ifdef CONFIG_PROC_FS
68 .show = crypto_sig_show,
69#endif
70#if IS_ENABLED(CONFIG_CRYPTO_USER)
71 .report = crypto_sig_report,
72#endif
73 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
74 .maskset = CRYPTO_ALG_TYPE_MASK,
75 .type = CRYPTO_ALG_TYPE_SIG,
76 .tfmsize = offsetof(struct crypto_sig, base),
77 .algsize = offsetof(struct sig_alg, base),
78};
79
80struct crypto_sig *crypto_alloc_sig(const char *alg_name, u32 type, u32 mask)
81{
82 return crypto_alloc_tfm(alg_name, frontend: &crypto_sig_type, type, mask);
83}
84EXPORT_SYMBOL_GPL(crypto_alloc_sig);
85
86static int sig_default_sign(struct crypto_sig *tfm,
87 const void *src, unsigned int slen,
88 void *dst, unsigned int dlen)
89{
90 return -ENOSYS;
91}
92
93static int sig_default_verify(struct crypto_sig *tfm,
94 const void *src, unsigned int slen,
95 const void *dst, unsigned int dlen)
96{
97 return -ENOSYS;
98}
99
100static int sig_default_set_key(struct crypto_sig *tfm,
101 const void *key, unsigned int keylen)
102{
103 return -ENOSYS;
104}
105
106static unsigned int sig_default_size(struct crypto_sig *tfm)
107{
108 return DIV_ROUND_UP_POW2(crypto_sig_keysize(tfm), BITS_PER_BYTE);
109}
110
111static int sig_prepare_alg(struct sig_alg *alg)
112{
113 struct crypto_alg *base = &alg->base;
114
115 if (!alg->sign)
116 alg->sign = sig_default_sign;
117 if (!alg->verify)
118 alg->verify = sig_default_verify;
119 if (!alg->set_priv_key)
120 alg->set_priv_key = sig_default_set_key;
121 if (!alg->set_pub_key)
122 return -EINVAL;
123 if (!alg->key_size)
124 return -EINVAL;
125 if (!alg->max_size)
126 alg->max_size = sig_default_size;
127 if (!alg->digest_size)
128 alg->digest_size = sig_default_size;
129
130 base->cra_type = &crypto_sig_type;
131 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
132 base->cra_flags |= CRYPTO_ALG_TYPE_SIG;
133
134 return 0;
135}
136
137int crypto_register_sig(struct sig_alg *alg)
138{
139 struct crypto_alg *base = &alg->base;
140 int err;
141
142 err = sig_prepare_alg(alg);
143 if (err)
144 return err;
145
146 return crypto_register_alg(alg: base);
147}
148EXPORT_SYMBOL_GPL(crypto_register_sig);
149
150void crypto_unregister_sig(struct sig_alg *alg)
151{
152 crypto_unregister_alg(alg: &alg->base);
153}
154EXPORT_SYMBOL_GPL(crypto_unregister_sig);
155
156int sig_register_instance(struct crypto_template *tmpl,
157 struct sig_instance *inst)
158{
159 int err;
160
161 if (WARN_ON(!inst->free))
162 return -EINVAL;
163
164 err = sig_prepare_alg(alg: &inst->alg);
165 if (err)
166 return err;
167
168 return crypto_register_instance(tmpl, inst: sig_crypto_instance(inst));
169}
170EXPORT_SYMBOL_GPL(sig_register_instance);
171
172int crypto_grab_sig(struct crypto_sig_spawn *spawn,
173 struct crypto_instance *inst,
174 const char *name, u32 type, u32 mask)
175{
176 spawn->base.frontend = &crypto_sig_type;
177 return crypto_grab_spawn(spawn: &spawn->base, inst, name, type, mask);
178}
179EXPORT_SYMBOL_GPL(crypto_grab_sig);
180
181MODULE_LICENSE("GPL");
182MODULE_DESCRIPTION("Public Key Signature Algorithms");
183