crypto/tls-cipher-suites.c

   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 "trace.h"
  18
  19 /*
  20  * IANA registered TLS ciphers:
  21  * https://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml#tls-parameters-4
  22  */
  23 typedef struct {
  24     uint8_t data[2];
  25 } QEMU_PACKED IANA_TLS_CIPHER;
  26
  27 GByteArray *qcrypto_tls_cipher_suites_get_data(QCryptoTLSCipherSuites *obj,
  28                                                Error **errp)
  29 {
  30     QCryptoTLSCreds *creds = QCRYPTO_TLS_CREDS(obj);
  31     gnutls_priority_t pcache;
  32     GByteArray *byte_array;
  33     const char *err;
  34     size_t i;
  35     int ret;
  36
  37     trace_qcrypto_tls_cipher_suite_priority(creds->priority);
  38     ret = gnutls_priority_init(&pcache, creds->priority, &err);
  39     if (ret < 0) {
  40         error_setg(errp, "Syntax error using priority '%s': %s",
  41                    creds->priority, gnutls_strerror(ret));
  42         return NULL;
  43     }
  44
  45     byte_array = g_byte_array_new();
  46
  47     for (i = 0;; i++) {
  48         int ret;
  49         unsigned idx;
  50         const char *name;
  51         IANA_TLS_CIPHER cipher;
  52         gnutls_protocol_t protocol;
  53         const char *version;
  54
  55         ret = gnutls_priority_get_cipher_suite_index(pcache, i, &idx);
  56         if (ret == GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE) {
  57             break;
  58         }
  59         if (ret == GNUTLS_E_UNKNOWN_CIPHER_SUITE) {
  60             continue;
  61         }
  62
  63         name = gnutls_cipher_suite_info(idx, (unsigned char *)&cipher,
  64                                         NULL, NULL, NULL, &protocol);
  65         if (name == NULL) {
  66             continue;
  67         }
  68
  69         version = gnutls_protocol_get_name(protocol);
  70         g_byte_array_append(byte_array, cipher.data, 2);
  71         trace_qcrypto_tls_cipher_suite_info(cipher.data[0],
  72                                             cipher.data[1],
  73                                             version, name);
  74     }
  75     trace_qcrypto_tls_cipher_suite_count(byte_array->len);
  76     gnutls_priority_deinit(pcache);
  77
  78     return byte_array;
  79 }
  80
  81 static void qcrypto_tls_cipher_suites_complete(UserCreatable *uc,
  82                                                Error **errp)
  83 {
  84     QCryptoTLSCreds *creds = QCRYPTO_TLS_CREDS(uc);
  85
  86     if (!creds->priority) {
  87         error_setg(errp, "'priority' property is not set");
  88         return;
  89     }
  90 }
  91
  92 static GByteArray *qcrypto_tls_cipher_suites_fw_cfg_gen_data(Object *obj,
  93                                                              Error **errp)
  94 {
  95     return qcrypto_tls_cipher_suites_get_data(QCRYPTO_TLS_CIPHER_SUITES(obj),
  96                                               errp);
  97 }
  98
  99 static void qcrypto_tls_cipher_suites_class_init(ObjectClass *oc, void *data)
 100 {
 101     UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
 102     FWCfgDataGeneratorClass *fwgc = FW_CFG_DATA_GENERATOR_CLASS(oc);
 103
 104     ucc->complete = qcrypto_tls_cipher_suites_complete;
 105     fwgc->get_data = qcrypto_tls_cipher_suites_fw_cfg_gen_data;
 106 }
 107
 108 static const TypeInfo qcrypto_tls_cipher_suites_info = {
 109     .parent = TYPE_QCRYPTO_TLS_CREDS,
 110     .name = TYPE_QCRYPTO_TLS_CIPHER_SUITES,
 111     .instance_size = sizeof(QCryptoTLSCreds),
 112     .class_size = sizeof(QCryptoTLSCredsClass),
 113     .class_init = qcrypto_tls_cipher_suites_class_init,
 114     .interfaces = (InterfaceInfo[]) {
 115         { TYPE_USER_CREATABLE },
 116         { TYPE_FW_CFG_DATA_GENERATOR_INTERFACE },
 117         { }
 118     }
 119 };
 120
 121 static void qcrypto_tls_cipher_suites_register_types(void)
 122 {
 123     type_register_static(&qcrypto_tls_cipher_suites_info);
 124 }
 125
 126 type_init(qcrypto_tls_cipher_suites_register_types);