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 "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);