MAINTAINERS: Make section QOM cover hw/core/*bus.c as well
[qemu/armbru.git] / include / crypto / secret.h
blob5e07e29bae4a0346dafe1221724708e0f8496b8d
1 /*
2 * QEMU crypto secret support
4 * Copyright (c) 2015 Red Hat, Inc.
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
21 #ifndef QCRYPTO_SECRET_H
22 #define QCRYPTO_SECRET_H
24 #include "qapi/qapi-types-crypto.h"
25 #include "qom/object.h"
27 #define TYPE_QCRYPTO_SECRET "secret"
28 #define QCRYPTO_SECRET(obj) \
29 OBJECT_CHECK(QCryptoSecret, (obj), TYPE_QCRYPTO_SECRET)
31 typedef struct QCryptoSecret QCryptoSecret;
32 typedef struct QCryptoSecretClass QCryptoSecretClass;
34 /**
35 * QCryptoSecret:
37 * The QCryptoSecret object provides storage of secrets,
38 * which may be user passwords, encryption keys or any
39 * other kind of sensitive data that is represented as
40 * a sequence of bytes.
42 * The sensitive data associated with the secret can
43 * be provided directly via the 'data' property, or
44 * indirectly via the 'file' property. In the latter
45 * case there is support for file descriptor passing
46 * via the usual /dev/fdset/NN syntax that QEMU uses.
48 * The data for a secret can be provided in two formats,
49 * either as a UTF-8 string (the default), or as base64
50 * encoded 8-bit binary data. The latter is appropriate
51 * for raw encryption keys, while the former is appropriate
52 * for user entered passwords.
54 * The data may be optionally encrypted with AES-256-CBC,
55 * and the decryption key provided by another
56 * QCryptoSecret instance identified by the 'keyid'
57 * property. When passing sensitive data directly
58 * via the 'data' property it is strongly recommended
59 * to use the AES encryption facility to prevent the
60 * sensitive data being exposed in the process listing
61 * or system log files.
63 * Providing data directly, insecurely (suitable for
64 * ad hoc developer testing only)
66 * $QEMU -object secret,id=sec0,data=letmein
68 * Providing data indirectly:
70 * # printf "letmein" > password.txt
71 * # $QEMU \
72 * -object secret,id=sec0,file=password.txt
74 * Using a master encryption key with data.
76 * The master key needs to be created as 32 secure
77 * random bytes (optionally base64 encoded)
79 * # openssl rand -base64 32 > key.b64
80 * # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X"')
82 * Each secret to be encrypted needs to have a random
83 * initialization vector generated. These do not need
84 * to be kept secret
86 * # openssl rand -base64 16 > iv.b64
87 * # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X"')
89 * A secret to be defined can now be encrypted
91 * # SECRET=$(printf "letmein" |
92 * openssl enc -aes-256-cbc -a -K $KEY -iv $IV)
94 * When launching QEMU, create a master secret pointing
95 * to key.b64 and specify that to be used to decrypt
96 * the user password
98 * # $QEMU \
99 * -object secret,id=secmaster0,format=base64,file=key.b64 \
100 * -object secret,id=sec0,keyid=secmaster0,format=base64,\
101 * data=$SECRET,iv=$(<iv.b64)
103 * When encrypting, the data can still be provided via an
104 * external file, in which case it is possible to use either
105 * raw binary data, or base64 encoded. This example uses
106 * raw format
108 * # printf "letmein" |
109 * openssl enc -aes-256-cbc -K $KEY -iv $IV -o pw.aes
110 * # $QEMU \
111 * -object secret,id=secmaster0,format=base64,file=key.b64 \
112 * -object secret,id=sec0,keyid=secmaster0,\
113 * file=pw.aes,iv=$(<iv.b64)
115 * Note that the ciphertext can be in either raw or base64
116 * format, as indicated by the 'format' parameter, but the
117 * plaintext resulting from decryption is expected to always
118 * be in raw format.
121 struct QCryptoSecret {
122 Object parent_obj;
123 uint8_t *rawdata;
124 size_t rawlen;
125 QCryptoSecretFormat format;
126 char *data;
127 char *file;
128 char *keyid;
129 char *iv;
133 struct QCryptoSecretClass {
134 ObjectClass parent_class;
138 extern int qcrypto_secret_lookup(const char *secretid,
139 uint8_t **data,
140 size_t *datalen,
141 Error **errp);
142 extern char *qcrypto_secret_lookup_as_utf8(const char *secretid,
143 Error **errp);
144 extern char *qcrypto_secret_lookup_as_base64(const char *secretid,
145 Error **errp);
147 #endif /* QCRYPTO_SECRET_H */