qemu

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/*
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 * QEMU TLS Cipher Suites
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 *
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 * Copyright (c) 2018-2020 Red Hat, Inc.
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 *
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 * Author: Philippe Mathieu-Daudé <philmd@redhat.com>
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 *
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 * SPDX-License-Identifier: GPL-2.0-or-later
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 */
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#include "qemu/osdep.h"
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#include "qapi/error.h"
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#include "qom/object_interfaces.h"
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#include "crypto/tlscreds.h"
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#include "crypto/tls-cipher-suites.h"
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#include "hw/nvram/fw_cfg.h"
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#include "tlscredspriv.h"
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#include "trace.h"
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struct QCryptoTLSCipherSuites {
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    /* <private> */
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    QCryptoTLSCreds parent_obj;
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    /* <public> */
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};
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/*
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 * IANA registered TLS ciphers:
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 * https://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml#tls-parameters-4
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 */
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typedef struct {
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    uint8_t data[2];
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} QEMU_PACKED IANA_TLS_CIPHER;
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GByteArray *qcrypto_tls_cipher_suites_get_data(QCryptoTLSCipherSuites *obj,
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                                               Error **errp)
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{
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    QCryptoTLSCreds *creds = QCRYPTO_TLS_CREDS(obj);
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    gnutls_priority_t pcache;
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    GByteArray *byte_array;
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    const char *err;
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    size_t i;
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    int ret;
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    trace_qcrypto_tls_cipher_suite_priority(creds->priority);
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    ret = gnutls_priority_init(&pcache, creds->priority, &err);
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    if (ret < 0) {
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        error_setg(errp, "Syntax error using priority '%s': %s",
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                   creds->priority, gnutls_strerror(ret));
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        return NULL;
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    }
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    byte_array = g_byte_array_new();
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    for (i = 0;; i++) {
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        unsigned idx;
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        const char *name;
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        IANA_TLS_CIPHER cipher;
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        gnutls_protocol_t protocol;
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        const char *version;
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        ret = gnutls_priority_get_cipher_suite_index(pcache, i, &idx);
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        if (ret == GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE) {
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            break;
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        }
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        if (ret == GNUTLS_E_UNKNOWN_CIPHER_SUITE) {
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            continue;
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        }
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        name = gnutls_cipher_suite_info(idx, (unsigned char *)&cipher,
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                                        NULL, NULL, NULL, &protocol);
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        if (name == NULL) {
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            continue;
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        }
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        version = gnutls_protocol_get_name(protocol);
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        g_byte_array_append(byte_array, cipher.data, 2);
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        trace_qcrypto_tls_cipher_suite_info(cipher.data[0],
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                                            cipher.data[1],
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                                            version, name);
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    }
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    trace_qcrypto_tls_cipher_suite_count(byte_array->len);
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    gnutls_priority_deinit(pcache);
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    return byte_array;
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}
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static void qcrypto_tls_cipher_suites_complete(UserCreatable *uc,
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                                               Error **errp)
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{
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    QCryptoTLSCreds *creds = QCRYPTO_TLS_CREDS(uc);
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    if (!creds->priority) {
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        error_setg(errp, "'priority' property is not set");
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        return;
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    }
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}
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static GByteArray *qcrypto_tls_cipher_suites_fw_cfg_gen_data(Object *obj,
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                                                             Error **errp)
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{
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    return qcrypto_tls_cipher_suites_get_data(QCRYPTO_TLS_CIPHER_SUITES(obj),
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                                              errp);
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}
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static void qcrypto_tls_cipher_suites_class_init(ObjectClass *oc, void *data)
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{
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    UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
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    FWCfgDataGeneratorClass *fwgc = FW_CFG_DATA_GENERATOR_CLASS(oc);
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    ucc->complete = qcrypto_tls_cipher_suites_complete;
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    fwgc->get_data = qcrypto_tls_cipher_suites_fw_cfg_gen_data;
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}
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static const TypeInfo qcrypto_tls_cipher_suites_info = {
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    .parent = TYPE_QCRYPTO_TLS_CREDS,
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    .name = TYPE_QCRYPTO_TLS_CIPHER_SUITES,
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    .instance_size = sizeof(QCryptoTLSCipherSuites),
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    .class_size = sizeof(QCryptoTLSCredsClass),
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    .class_init = qcrypto_tls_cipher_suites_class_init,
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    .interfaces = (InterfaceInfo[]) {
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        { TYPE_USER_CREATABLE },
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        { TYPE_FW_CFG_DATA_GENERATOR_INTERFACE },
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        { }
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    }
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};
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static void qcrypto_tls_cipher_suites_register_types(void)
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{
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    type_register_static(&qcrypto_tls_cipher_suites_info);
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}
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type_init(qcrypto_tls_cipher_suites_register_types);
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