xref: /freebsd/sys/crypto/openssl/ossl_aes.c (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2021 Stormshield.
5  * Copyright (c) 2021 Semihalf.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 #include <sys/param.h>
30 #include <sys/malloc.h>
31 
32 #include <opencrypto/cryptodev.h>
33 #include <opencrypto/gmac.h>
34 
35 #include <crypto/openssl/ossl.h>
36 #include <crypto/openssl/ossl_aes_gcm.h>
37 #include <crypto/openssl/ossl_cipher.h>
38 
39 #if defined(__amd64__) || defined(__i386__)
40 #include <crypto/openssl/ossl_x86.h>
41 #elif defined (__aarch64__)
42 #include <crypto/openssl/ossl_aarch64.h>
43 #endif
44 
45 static ossl_cipher_process_t ossl_aes_cbc;
46 static ossl_cipher_process_t ossl_aes_gcm;
47 
48 struct ossl_cipher ossl_cipher_aes_cbc = {
49 	.type = CRYPTO_AES_CBC,
50 	.blocksize = AES_BLOCK_LEN,
51 	.ivsize = AES_BLOCK_LEN,
52 
53 	/* Filled during initialization based on CPU caps. */
54 	.set_encrypt_key = NULL,
55 	.set_decrypt_key = NULL,
56 	.process = ossl_aes_cbc
57 };
58 
59 struct ossl_cipher ossl_cipher_aes_gcm = {
60 	.type = CRYPTO_AES_NIST_GCM_16,
61 	.blocksize = 1,
62 	.ivsize = AES_GCM_IV_LEN,
63 
64 	/* Filled during initialization based on CPU caps. */
65 	.set_encrypt_key = NULL,
66 	.set_decrypt_key = NULL,
67 	.process = ossl_aes_gcm,
68 };
69 
70 static int
71 ossl_aes_cbc(struct ossl_session_cipher *s, struct cryptop *crp,
72     const struct crypto_session_params *csp)
73 {
74 	struct crypto_buffer_cursor cc_in, cc_out;
75 	unsigned char block[EALG_MAX_BLOCK_LEN];
76 	unsigned char iv[EALG_MAX_BLOCK_LEN];
77 	const unsigned char *in, *inseg;
78 	unsigned char *out, *outseg;
79 	size_t plen, seglen, inlen, outlen;
80 	struct ossl_cipher_context key;
81 	struct ossl_cipher *cipher;
82 	int blocklen, error;
83 	bool encrypt;
84 
85 	cipher = s->cipher;
86 	encrypt = CRYPTO_OP_IS_ENCRYPT(crp->crp_op);
87 	plen = crp->crp_payload_length;
88 	blocklen = cipher->blocksize;
89 
90 	if (plen % blocklen)
91 		return (EINVAL);
92 
93 	if (crp->crp_cipher_key != NULL) {
94 		if (encrypt)
95 			error = cipher->set_encrypt_key(crp->crp_cipher_key,
96 			    8 * csp->csp_cipher_klen, &key);
97 		else
98 			error = cipher->set_decrypt_key(crp->crp_cipher_key,
99 			    8 * csp->csp_cipher_klen, &key);
100 		if (error)
101 			return (error);
102 	} else {
103 		if (encrypt)
104 			key = s->enc_ctx;
105 		else
106 			key = s->dec_ctx;
107 	}
108 
109 	crypto_read_iv(crp, iv);
110 
111 	/* Derived from ossl_chacha20.c */
112 	crypto_cursor_init(&cc_in, &crp->crp_buf);
113 	crypto_cursor_advance(&cc_in, crp->crp_payload_start);
114 	inseg = crypto_cursor_segment(&cc_in, &inlen);
115 	if (CRYPTO_HAS_OUTPUT_BUFFER(crp)) {
116 		crypto_cursor_init(&cc_out, &crp->crp_obuf);
117 		crypto_cursor_advance(&cc_out, crp->crp_payload_output_start);
118 	} else {
119 		cc_out = cc_in;
120 	}
121 	outseg = crypto_cursor_segment(&cc_out, &outlen);
122 
123 	while (plen >= blocklen) {
124 		if (inlen < blocklen) {
125 			crypto_cursor_copydata(&cc_in, blocklen, block);
126 			in = block;
127 			inlen = blocklen;
128 		} else {
129 			in = inseg;
130 		}
131 		if (outlen < blocklen) {
132 			out = block;
133 			outlen = blocklen;
134 		} else {
135 			out = outseg;
136 		}
137 
138 		/* Figure out how many blocks we can encrypt/decrypt at once. */
139 		seglen = rounddown(MIN(plen, MIN(inlen, outlen)), blocklen);
140 
141 		AES_CBC_ENCRYPT(in, out, seglen, &key, iv, encrypt);
142 
143 		if (out == block) {
144 			crypto_cursor_copyback(&cc_out, blocklen, block);
145 			outseg = crypto_cursor_segment(&cc_out, &outlen);
146 		} else {
147 			crypto_cursor_advance(&cc_out, seglen);
148 			outseg += seglen;
149 			outlen -= seglen;
150 		}
151 		if (in == block) {
152 			inseg = crypto_cursor_segment(&cc_in, &inlen);
153 		} else {
154 			crypto_cursor_advance(&cc_in, seglen);
155 			inseg += seglen;
156 			inlen -= seglen;
157 		}
158 		plen -= seglen;
159 	}
160 
161 	explicit_bzero(block, sizeof(block));
162 	explicit_bzero(iv, sizeof(iv));
163 	explicit_bzero(&key, sizeof(key));
164 	return (0);
165 }
166 
167 static int
168 ossl_aes_gcm(struct ossl_session_cipher *s, struct cryptop *crp,
169     const struct crypto_session_params *csp)
170 {
171 	struct ossl_cipher_context key;
172 	struct crypto_buffer_cursor cc_in, cc_out;
173 	unsigned char iv[AES_BLOCK_LEN], tag[AES_BLOCK_LEN];
174 	struct ossl_gcm_context *ctx;
175 	const unsigned char *inseg;
176 	unsigned char *outseg;
177 	size_t inlen, outlen, seglen;
178 	int error;
179 	bool encrypt;
180 
181 	encrypt = CRYPTO_OP_IS_ENCRYPT(crp->crp_op);
182 
183 	if (crp->crp_cipher_key != NULL) {
184 		if (encrypt)
185 			error = s->cipher->set_encrypt_key(crp->crp_cipher_key,
186 			    8 * csp->csp_cipher_klen, &key);
187 		else
188 			error = s->cipher->set_decrypt_key(crp->crp_cipher_key,
189 			    8 * csp->csp_cipher_klen, &key);
190 		if (error)
191 			return (error);
192 		ctx = (struct ossl_gcm_context *)&key;
193 	} else if (encrypt) {
194 		ctx = (struct ossl_gcm_context *)&s->enc_ctx;
195 	} else {
196 		ctx = (struct ossl_gcm_context *)&s->dec_ctx;
197 	}
198 
199 	crypto_read_iv(crp, iv);
200 	ctx->ops->setiv(ctx, iv, csp->csp_ivlen);
201 
202 	crypto_cursor_init(&cc_in, &crp->crp_buf);
203 	crypto_cursor_advance(&cc_in, crp->crp_aad_start);
204 	for (size_t alen = crp->crp_aad_length; alen > 0; alen -= seglen) {
205 		inseg = crypto_cursor_segment(&cc_in, &inlen);
206 		seglen = MIN(alen, inlen);
207 		if (ctx->ops->aad(ctx, inseg, seglen) != 0)
208 			return (EINVAL);
209 		crypto_cursor_advance(&cc_in, seglen);
210 	}
211 
212 	crypto_cursor_init(&cc_in, &crp->crp_buf);
213 	crypto_cursor_advance(&cc_in, crp->crp_payload_start);
214 	if (CRYPTO_HAS_OUTPUT_BUFFER(crp)) {
215 		crypto_cursor_init(&cc_out, &crp->crp_obuf);
216 		crypto_cursor_advance(&cc_out, crp->crp_payload_output_start);
217 	} else {
218 		cc_out = cc_in;
219 	}
220 
221 	for (size_t plen = crp->crp_payload_length; plen > 0; plen -= seglen) {
222 		inseg = crypto_cursor_segment(&cc_in, &inlen);
223 		outseg = crypto_cursor_segment(&cc_out, &outlen);
224 		seglen = MIN(plen, MIN(inlen, outlen));
225 
226 		if (encrypt) {
227 			if (ctx->ops->encrypt(ctx, inseg, outseg, seglen) != 0)
228 				return (EINVAL);
229 		} else {
230 			if (ctx->ops->decrypt(ctx, inseg, outseg, seglen) != 0)
231 				return (EINVAL);
232 		}
233 
234 		crypto_cursor_advance(&cc_in, seglen);
235 		crypto_cursor_advance(&cc_out, seglen);
236 	}
237 
238 	error = 0;
239 	if (encrypt) {
240 		ctx->ops->tag(ctx, tag, GMAC_DIGEST_LEN);
241 		crypto_copyback(crp, crp->crp_digest_start, GMAC_DIGEST_LEN,
242 		    tag);
243 	} else {
244 		crypto_copydata(crp, crp->crp_digest_start, GMAC_DIGEST_LEN,
245 		    tag);
246 		if (ctx->ops->finish(ctx, tag, GMAC_DIGEST_LEN) != 0)
247 			error = EBADMSG;
248 	}
249 
250 	explicit_bzero(iv, sizeof(iv));
251 	explicit_bzero(tag, sizeof(tag));
252 
253 	return (error);
254 }
255