Merge tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux
[platform/kernel/linux-rpi.git] / crypto / geniv.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * geniv: Shared IV generator code
4  *
5  * This file provides common code to IV generators such as seqiv.
6  *
7  * Copyright (c) 2007-2019 Herbert Xu <herbert@gondor.apana.org.au>
8  */
9
10 #include <crypto/internal/geniv.h>
11 #include <crypto/internal/rng.h>
12 #include <crypto/null.h>
13 #include <linux/err.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/rtnetlink.h>
17 #include <linux/slab.h>
18
19 static int aead_geniv_setkey(struct crypto_aead *tfm,
20                              const u8 *key, unsigned int keylen)
21 {
22         struct aead_geniv_ctx *ctx = crypto_aead_ctx(tfm);
23
24         return crypto_aead_setkey(ctx->child, key, keylen);
25 }
26
27 static int aead_geniv_setauthsize(struct crypto_aead *tfm,
28                                   unsigned int authsize)
29 {
30         struct aead_geniv_ctx *ctx = crypto_aead_ctx(tfm);
31
32         return crypto_aead_setauthsize(ctx->child, authsize);
33 }
34
35 static void aead_geniv_free(struct aead_instance *inst)
36 {
37         crypto_drop_aead(aead_instance_ctx(inst));
38         kfree(inst);
39 }
40
41 struct aead_instance *aead_geniv_alloc(struct crypto_template *tmpl,
42                                        struct rtattr **tb)
43 {
44         struct crypto_aead_spawn *spawn;
45         struct aead_instance *inst;
46         struct aead_alg *alg;
47         unsigned int ivsize;
48         unsigned int maxauthsize;
49         u32 mask;
50         int err;
51
52         err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD, &mask);
53         if (err)
54                 return ERR_PTR(err);
55
56         inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
57         if (!inst)
58                 return ERR_PTR(-ENOMEM);
59
60         spawn = aead_instance_ctx(inst);
61
62         err = crypto_grab_aead(spawn, aead_crypto_instance(inst),
63                                crypto_attr_alg_name(tb[1]), 0, mask);
64         if (err)
65                 goto err_free_inst;
66
67         alg = crypto_spawn_aead_alg(spawn);
68
69         ivsize = crypto_aead_alg_ivsize(alg);
70         maxauthsize = crypto_aead_alg_maxauthsize(alg);
71
72         err = -EINVAL;
73         if (ivsize < sizeof(u64))
74                 goto err_free_inst;
75
76         err = -ENAMETOOLONG;
77         if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
78                      "%s(%s)", tmpl->name, alg->base.cra_name) >=
79             CRYPTO_MAX_ALG_NAME)
80                 goto err_free_inst;
81         if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
82                      "%s(%s)", tmpl->name, alg->base.cra_driver_name) >=
83             CRYPTO_MAX_ALG_NAME)
84                 goto err_free_inst;
85
86         inst->alg.base.cra_priority = alg->base.cra_priority;
87         inst->alg.base.cra_blocksize = alg->base.cra_blocksize;
88         inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
89         inst->alg.base.cra_ctxsize = sizeof(struct aead_geniv_ctx);
90
91         inst->alg.setkey = aead_geniv_setkey;
92         inst->alg.setauthsize = aead_geniv_setauthsize;
93
94         inst->alg.ivsize = ivsize;
95         inst->alg.maxauthsize = maxauthsize;
96
97         inst->free = aead_geniv_free;
98
99 out:
100         return inst;
101
102 err_free_inst:
103         aead_geniv_free(inst);
104         inst = ERR_PTR(err);
105         goto out;
106 }
107 EXPORT_SYMBOL_GPL(aead_geniv_alloc);
108
109 int aead_init_geniv(struct crypto_aead *aead)
110 {
111         struct aead_geniv_ctx *ctx = crypto_aead_ctx(aead);
112         struct aead_instance *inst = aead_alg_instance(aead);
113         struct crypto_aead *child;
114         int err;
115
116         spin_lock_init(&ctx->lock);
117
118         err = crypto_get_default_rng();
119         if (err)
120                 goto out;
121
122         err = crypto_rng_get_bytes(crypto_default_rng, ctx->salt,
123                                    crypto_aead_ivsize(aead));
124         crypto_put_default_rng();
125         if (err)
126                 goto out;
127
128         ctx->sknull = crypto_get_default_null_skcipher();
129         err = PTR_ERR(ctx->sknull);
130         if (IS_ERR(ctx->sknull))
131                 goto out;
132
133         child = crypto_spawn_aead(aead_instance_ctx(inst));
134         err = PTR_ERR(child);
135         if (IS_ERR(child))
136                 goto drop_null;
137
138         ctx->child = child;
139         crypto_aead_set_reqsize(aead, crypto_aead_reqsize(child) +
140                                       sizeof(struct aead_request));
141
142         err = 0;
143
144 out:
145         return err;
146
147 drop_null:
148         crypto_put_default_null_skcipher();
149         goto out;
150 }
151 EXPORT_SYMBOL_GPL(aead_init_geniv);
152
153 void aead_exit_geniv(struct crypto_aead *tfm)
154 {
155         struct aead_geniv_ctx *ctx = crypto_aead_ctx(tfm);
156
157         crypto_free_aead(ctx->child);
158         crypto_put_default_null_skcipher();
159 }
160 EXPORT_SYMBOL_GPL(aead_exit_geniv);
161
162 MODULE_LICENSE("GPL");
163 MODULE_DESCRIPTION("Shared IV generator code");