xref: /openbmc/qemu/crypto/tls-cipher-suites.c (revision a6caeee8)
1 /*
2  * QEMU TLS Cipher Suites
3  *
4  * Copyright (c) 2018-2020 Red Hat, Inc.
5  *
6  * Author: Philippe Mathieu-Daudé <philmd@redhat.com>
7  *
8  * SPDX-License-Identifier: GPL-2.0-or-later
9  */
10 
11 #include "qemu/osdep.h"
12 #include "qapi/error.h"
13 #include "qom/object_interfaces.h"
14 #include "crypto/tlscreds.h"
15 #include "crypto/tls-cipher-suites.h"
16 #include "hw/nvram/fw_cfg.h"
17 #include "tlscredspriv.h"
18 #include "trace.h"
19 
20 struct QCryptoTLSCipherSuites {
21     /* <private> */
22     QCryptoTLSCreds parent_obj;
23     /* <public> */
24 };
25 
26 /*
27  * IANA registered TLS ciphers:
28  * https://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml#tls-parameters-4
29  */
30 typedef struct {
31     uint8_t data[2];
32 } QEMU_PACKED IANA_TLS_CIPHER;
33 
34 GByteArray *qcrypto_tls_cipher_suites_get_data(QCryptoTLSCipherSuites *obj,
35                                                Error **errp)
36 {
37     QCryptoTLSCreds *creds = QCRYPTO_TLS_CREDS(obj);
38     gnutls_priority_t pcache;
39     GByteArray *byte_array;
40     const char *err;
41     size_t i;
42     int ret;
43 
44     trace_qcrypto_tls_cipher_suite_priority(creds->priority);
45     ret = gnutls_priority_init(&pcache, creds->priority, &err);
46     if (ret < 0) {
47         error_setg(errp, "Syntax error using priority '%s': %s",
48                    creds->priority, gnutls_strerror(ret));
49         return NULL;
50     }
51 
52     byte_array = g_byte_array_new();
53 
54     for (i = 0;; i++) {
55         int ret;
56         unsigned idx;
57         const char *name;
58         IANA_TLS_CIPHER cipher;
59         gnutls_protocol_t protocol;
60         const char *version;
61 
62         ret = gnutls_priority_get_cipher_suite_index(pcache, i, &idx);
63         if (ret == GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE) {
64             break;
65         }
66         if (ret == GNUTLS_E_UNKNOWN_CIPHER_SUITE) {
67             continue;
68         }
69 
70         name = gnutls_cipher_suite_info(idx, (unsigned char *)&cipher,
71                                         NULL, NULL, NULL, &protocol);
72         if (name == NULL) {
73             continue;
74         }
75 
76         version = gnutls_protocol_get_name(protocol);
77         g_byte_array_append(byte_array, cipher.data, 2);
78         trace_qcrypto_tls_cipher_suite_info(cipher.data[0],
79                                             cipher.data[1],
80                                             version, name);
81     }
82     trace_qcrypto_tls_cipher_suite_count(byte_array->len);
83     gnutls_priority_deinit(pcache);
84 
85     return byte_array;
86 }
87 
88 static void qcrypto_tls_cipher_suites_complete(UserCreatable *uc,
89                                                Error **errp)
90 {
91     QCryptoTLSCreds *creds = QCRYPTO_TLS_CREDS(uc);
92 
93     if (!creds->priority) {
94         error_setg(errp, "'priority' property is not set");
95         return;
96     }
97 }
98 
99 static GByteArray *qcrypto_tls_cipher_suites_fw_cfg_gen_data(Object *obj,
100                                                              Error **errp)
101 {
102     return qcrypto_tls_cipher_suites_get_data(QCRYPTO_TLS_CIPHER_SUITES(obj),
103                                               errp);
104 }
105 
106 static void qcrypto_tls_cipher_suites_class_init(ObjectClass *oc, void *data)
107 {
108     UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
109     FWCfgDataGeneratorClass *fwgc = FW_CFG_DATA_GENERATOR_CLASS(oc);
110 
111     ucc->complete = qcrypto_tls_cipher_suites_complete;
112     fwgc->get_data = qcrypto_tls_cipher_suites_fw_cfg_gen_data;
113 }
114 
115 static const TypeInfo qcrypto_tls_cipher_suites_info = {
116     .parent = TYPE_QCRYPTO_TLS_CREDS,
117     .name = TYPE_QCRYPTO_TLS_CIPHER_SUITES,
118     .instance_size = sizeof(QCryptoTLSCipherSuites),
119     .class_size = sizeof(QCryptoTLSCredsClass),
120     .class_init = qcrypto_tls_cipher_suites_class_init,
121     .interfaces = (InterfaceInfo[]) {
122         { TYPE_USER_CREATABLE },
123         { TYPE_FW_CFG_DATA_GENERATOR_INTERFACE },
124         { }
125     }
126 };
127 
128 static void qcrypto_tls_cipher_suites_register_types(void)
129 {
130     type_register_static(&qcrypto_tls_cipher_suites_info);
131 }
132 
133 type_init(qcrypto_tls_cipher_suites_register_types);
134