xref: /openbmc/qemu/crypto/tls-cipher-suites.c (revision 7c08eefc)
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         unsigned idx;
56         const char *name;
57         IANA_TLS_CIPHER cipher;
58         gnutls_protocol_t protocol;
59         const char *version;
60 
61         ret = gnutls_priority_get_cipher_suite_index(pcache, i, &idx);
62         if (ret == GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE) {
63             break;
64         }
65         if (ret == GNUTLS_E_UNKNOWN_CIPHER_SUITE) {
66             continue;
67         }
68 
69         name = gnutls_cipher_suite_info(idx, (unsigned char *)&cipher,
70                                         NULL, NULL, NULL, &protocol);
71         if (name == NULL) {
72             continue;
73         }
74 
75         version = gnutls_protocol_get_name(protocol);
76         g_byte_array_append(byte_array, cipher.data, 2);
77         trace_qcrypto_tls_cipher_suite_info(cipher.data[0],
78                                             cipher.data[1],
79                                             version, name);
80     }
81     trace_qcrypto_tls_cipher_suite_count(byte_array->len);
82     gnutls_priority_deinit(pcache);
83 
84     return byte_array;
85 }
86 
87 static void qcrypto_tls_cipher_suites_complete(UserCreatable *uc,
88                                                Error **errp)
89 {
90     QCryptoTLSCreds *creds = QCRYPTO_TLS_CREDS(uc);
91 
92     if (!creds->priority) {
93         error_setg(errp, "'priority' property is not set");
94         return;
95     }
96 }
97 
98 static GByteArray *qcrypto_tls_cipher_suites_fw_cfg_gen_data(Object *obj,
99                                                              Error **errp)
100 {
101     return qcrypto_tls_cipher_suites_get_data(QCRYPTO_TLS_CIPHER_SUITES(obj),
102                                               errp);
103 }
104 
105 static void qcrypto_tls_cipher_suites_class_init(ObjectClass *oc, void *data)
106 {
107     UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
108     FWCfgDataGeneratorClass *fwgc = FW_CFG_DATA_GENERATOR_CLASS(oc);
109 
110     ucc->complete = qcrypto_tls_cipher_suites_complete;
111     fwgc->get_data = qcrypto_tls_cipher_suites_fw_cfg_gen_data;
112 }
113 
114 static const TypeInfo qcrypto_tls_cipher_suites_info = {
115     .parent = TYPE_QCRYPTO_TLS_CREDS,
116     .name = TYPE_QCRYPTO_TLS_CIPHER_SUITES,
117     .instance_size = sizeof(QCryptoTLSCipherSuites),
118     .class_size = sizeof(QCryptoTLSCredsClass),
119     .class_init = qcrypto_tls_cipher_suites_class_init,
120     .interfaces = (InterfaceInfo[]) {
121         { TYPE_USER_CREATABLE },
122         { TYPE_FW_CFG_DATA_GENERATOR_INTERFACE },
123         { }
124     }
125 };
126 
127 static void qcrypto_tls_cipher_suites_register_types(void)
128 {
129     type_register_static(&qcrypto_tls_cipher_suites_info);
130 }
131 
132 type_init(qcrypto_tls_cipher_suites_register_types);
133