xref: /illumos-gate/usr/src/lib/pkcs11/libpkcs11/common/metaRand.c (revision 7c478bd95313f5f23a4c958a745db2134aa03244)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 /*
30  * Random Number Generation Functions
31  * (as defined in PKCS#11 spec section 11.15)
32  *
33  */
34 
35 #include <sys/types.h>
36 #include <sys/stat.h>
37 #include <fcntl.h>
38 #include <errno.h>
39 #include <string.h>
40 
41 #include "metaGlobal.h"
42 
43 /*
44  * meta_SeedRandom
45  *
46  * Unlike most other metaslot functions, meta_SeedRandom does not distribute
47  * the call to a specific provider. Rather, we assume that the /dev/urandom
48  * implementation is a kCF consumer, and is pulling randomness from everywhere
49  * it can. Thus, by seeding /dev/urandom we let kCF potentially do all the
50  * work.
51  *
52  * NOTES:
53  * 1) /dev/urandom vs. /dev/random... Unfortunately P11 does not allow app
54  *    to request a "quality", so we'll just assume urandom is good enough.
55  *    Concerned apps can pull hardcore randomness from specific places they
56  *    trust (eg by checking for CKF_HW?)..
57  *
58  */
59 CK_RV
60 meta_SeedRandom(CK_SESSION_HANDLE hSession, CK_BYTE_PTR pSeed,
61     CK_ULONG ulSeedLen)
62 {
63 	CK_RV rv;
64 	meta_session_t *session;
65 	int fd;
66 	ssize_t n;
67 
68 	if (pSeed == NULL || ulSeedLen == 0)
69 		return (CKR_ARGUMENTS_BAD);
70 
71 	/* Just check handle for validity, we don't need it for anything. */
72 	rv = meta_handle2session(hSession, &session);
73 	if (rv != CKR_OK)
74 		return (rv);
75 	REFRELEASE(session);
76 
77 	while ((fd = open(RANDOM_DEVICE, O_WRONLY)) < 0) {
78 		if (errno != EINTR)
79 			break;
80 	}
81 	if (fd == -1) {
82 		if (errno == EACCES)
83 			return (CKR_RANDOM_SEED_NOT_SUPPORTED);
84 		else
85 			return (CKR_DEVICE_ERROR);
86 	}
87 
88 	n = looping_write(fd, pSeed, ulSeedLen);
89 	if (n <= 0) {
90 		(void) close(fd);
91 		return (CKR_DEVICE_ERROR);
92 	}
93 
94 	(void) close(fd);
95 
96 	return (CKR_OK);
97 }
98 
99 /*
100  * meta_GenerateRandom
101  *
102  * Unlike most other metaslot functions, meta_GenerateRandom does not distribute
103  * the call to a specific provider. Rather, we assume that the /dev/urandom
104  * implementation is a kCF consumer, and is pulling randomness from everywhere
105  * it can. Thus, by reading /dev/urandom we let kCF potentially do all the
106  * work.
107  *
108  */
109 CK_RV
110 meta_GenerateRandom(CK_SESSION_HANDLE hSession, CK_BYTE_PTR pRandomData,
111     CK_ULONG ulRandomLen)
112 {
113 	CK_RV rv;
114 	meta_session_t *session;
115 	int fd;
116 	ssize_t n;
117 
118 	if (pRandomData == NULL || ulRandomLen < 1)
119 		return (CKR_ARGUMENTS_BAD);
120 
121 	/* Just check handle for validity, we don't need it for anything. */
122 	rv = meta_handle2session(hSession, &session);
123 	if (rv != CKR_OK)
124 		return (rv);
125 	REFRELEASE(session);
126 
127 	while ((fd = open(RANDOM_DEVICE, O_RDONLY)) < 0) {
128 		if (errno != EINTR)
129 			break;
130 	}
131 	if (fd == -1) {
132 		return (CKR_DEVICE_ERROR);
133 	}
134 
135 	n = looping_read(fd, pRandomData, ulRandomLen);
136 	if (n <= 0) {
137 		(void) close(fd);
138 		return (CKR_DEVICE_ERROR);
139 	}
140 
141 	(void) close(fd);
142 
143 	return (CKR_OK);
144 }
145