xref: /dragonfly/lib/libtcplay/crypto-dev.c (revision cfd1aba3)
1 /*
2  * Copyright (c) 2011 Alex Hornung <alex@alexhornung.com>.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in
13  *    the documentation and/or other materials provided with the
14  *    distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
19  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
20  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
22  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
24  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
25  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
26  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 #include <sys/types.h>
30 #include <sys/param.h>
31 #include <sys/ioctl.h>
32 #include <sys/sysctl.h>
33 #include <crypto/cryptodev.h>
34 
35 #include <fcntl.h>
36 #include <unistd.h>
37 #include <errno.h>
38 #include <string.h>
39 #include <stdio.h>
40 
41 #include "tcplay.h"
42 
43 static
44 int
45 getallowsoft(void)
46 {
47 	int old;
48 	size_t olen;
49 
50 	olen = sizeof(old);
51 
52 	if (sysctlbyname("kern.cryptodevallowsoft", &old, &olen, NULL, 0) < 0) {
53 		perror("accessing sysctl kern.cryptodevallowsoft failed");
54 	}
55 
56 	return old;
57 }
58 
59 static
60 void
61 setallowsoft(int new)
62 {
63 	int old;
64 	size_t olen, nlen;
65 
66 	olen = nlen = sizeof(new);
67 
68 	if (sysctlbyname("kern.cryptodevallowsoft", &old, &olen, &new, nlen) < 0) {
69 		perror("accessing sysctl kern.cryptodevallowsoft failed");
70 	}
71 }
72 
73 static
74 int
75 get_cryptodev_cipher_id(struct tc_crypto_algo *cipher)
76 {
77 	if	(strcmp(cipher->name, "AES-128-XTS") == 0)
78 		return CRYPTO_AES_XTS;
79 	else if (strcmp(cipher->name, "AES-256-XTS") == 0)
80 		return CRYPTO_AES_XTS;
81 	else if (strcmp(cipher->name, "TWOFISH-128-XTS") == 0)
82 		return CRYPTO_TWOFISH_XTS;
83 	else if (strcmp(cipher->name, "TWOFISH-256-XTS") == 0)
84 		return CRYPTO_TWOFISH_XTS;
85 	else if (strcmp(cipher->name, "SERPENT-128-XTS") == 0)
86 		return CRYPTO_SERPENT_XTS;
87 	else if (strcmp(cipher->name, "SERPENT-256-XTS") == 0)
88 		return CRYPTO_SERPENT_XTS;
89 	else
90 		return -1;
91 }
92 
93 int
94 syscrypt(struct tc_crypto_algo *cipher, unsigned char *key, size_t klen, unsigned char *iv,
95     unsigned char *in, unsigned char *out, size_t len, int do_encrypt)
96 {
97 	struct session_op session;
98 	struct crypt_op cryp;
99 	int cipher_id;
100 	int cryptodev_fd = -1, fd = -1;
101 
102 	cipher_id = get_cryptodev_cipher_id(cipher);
103 	if (cipher_id < 0) {
104 		tc_log(1, "Cipher %s not found\n",
105 		    cipher->name);
106 		return ENOENT;
107 	}
108 
109 	if ((cryptodev_fd = open("/dev/crypto", O_RDWR, 0)) < 0) {
110 		perror("Could not open /dev/crypto");
111 		goto err;
112 	}
113 	if (ioctl(cryptodev_fd, CRIOGET, &fd) == -1) {
114 		perror("CRIOGET failed");
115 		goto err;
116 	}
117 	memset(&session, 0, sizeof(session));
118 	session.cipher = cipher_id;
119 	session.key = (caddr_t) key;
120 	session.keylen = klen;
121 	if (ioctl(fd, CIOCGSESSION, &session) == -1) {
122 		perror("CIOCGSESSION failed");
123 		goto err;
124 	}
125 	memset(&cryp, 0, sizeof(cryp));
126 	cryp.ses = session.ses;
127 	cryp.op = do_encrypt ? COP_ENCRYPT : COP_DECRYPT;
128 	cryp.flags = 0;
129 	cryp.len = len;
130 	cryp.src = (caddr_t) in;
131 	cryp.dst = (caddr_t) out;
132 	cryp.iv = (caddr_t) iv;
133 	cryp.mac = 0;
134 	if (ioctl(fd, CIOCCRYPT, &cryp) == -1) {
135 		perror("CIOCCRYPT failed");
136 		goto err;
137 	}
138 	if (ioctl(fd, CIOCFSESSION, &session.ses) == -1) {
139 		perror("CIOCFSESSION failed");
140 		goto err;
141 	}
142 	close(fd);
143 	close(cryptodev_fd);
144 	return (0);
145 
146 err:
147 	if (fd != -1)
148 		close(fd);
149 	if (cryptodev_fd != -1)
150 		close(cryptodev_fd);
151 	return (-1);
152 }
153 
154 int
155 tc_crypto_init(void)
156 {
157 	int allowed;
158 
159 	allowed = getallowsoft();
160 	if (allowed == 0)
161 		setallowsoft(1);
162 
163 	return 0;
164 }
165 
166