[PATCH v7 4/5] crypto: Add tls-cipher-suites object

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

Example of use to dump:

  $ qemu-system-x86_64 -S \
    -object tls-cipher-suites,id=mysuite,priority=@SYSTEM \
    -trace qcrypto\*
  1590664444.197123:qcrypto_tls_cipher_suite_priority priority: @SYSTEM
  1590664444.197219:qcrypto_tls_cipher_suite_info data:[0x13, 0x02] version:TLS1.3 name:TLS_AES_256_GCM_SHA384
  1590664444.197228:qcrypto_tls_cipher_suite_info data:[0x13, 0x03] version:TLS1.3 name:TLS_CHACHA20_POLY1305_SHA256
  1590664444.197233:qcrypto_tls_cipher_suite_info data:[0x13, 0x01] version:TLS1.3 name:TLS_AES_128_GCM_SHA256
  1590664444.197236:qcrypto_tls_cipher_suite_info data:[0x13, 0x04] version:TLS1.3 name:TLS_AES_128_CCM_SHA256
  1590664444.197240:qcrypto_tls_cipher_suite_info data:[0xc0, 0x30] version:TLS1.2 name:TLS_ECDHE_RSA_AES_256_GCM_SHA384
  1590664444.197245:qcrypto_tls_cipher_suite_info data:[0xcc, 0xa8] version:TLS1.2 name:TLS_ECDHE_RSA_CHACHA20_POLY1305
  1590664444.197250:qcrypto_tls_cipher_suite_info data:[0xc0, 0x14] version:TLS1.0 name:TLS_ECDHE_RSA_AES_256_CBC_SHA1
  1590664444.197254:qcrypto_tls_cipher_suite_info data:[0xc0, 0x2f] version:TLS1.2 name:TLS_ECDHE_RSA_AES_128_GCM_SHA256
  1590664444.197258:qcrypto_tls_cipher_suite_info data:[0xc0, 0x13] version:TLS1.0 name:TLS_ECDHE_RSA_AES_128_CBC_SHA1
  1590664444.197261:qcrypto_tls_cipher_suite_info data:[0xc0, 0x2c] version:TLS1.2 name:TLS_ECDHE_ECDSA_AES_256_GCM_SHA384
  1590664444.197266:qcrypto_tls_cipher_suite_info data:[0xcc, 0xa9] version:TLS1.2 name:TLS_ECDHE_ECDSA_CHACHA20_POLY1305
  1590664444.197270:qcrypto_tls_cipher_suite_info data:[0xc0, 0xad] version:TLS1.2 name:TLS_ECDHE_ECDSA_AES_256_CCM
  1590664444.197274:qcrypto_tls_cipher_suite_info data:[0xc0, 0x0a] version:TLS1.0 name:TLS_ECDHE_ECDSA_AES_256_CBC_SHA1
  1590664444.197278:qcrypto_tls_cipher_suite_info data:[0xc0, 0x2b] version:TLS1.2 name:TLS_ECDHE_ECDSA_AES_128_GCM_SHA256
  1590664444.197283:qcrypto_tls_cipher_suite_info data:[0xc0, 0xac] version:TLS1.2 name:TLS_ECDHE_ECDSA_AES_128_CCM
  1590664444.197287:qcrypto_tls_cipher_suite_info data:[0xc0, 0x09] version:TLS1.0 name:TLS_ECDHE_ECDSA_AES_128_CBC_SHA1
  1590664444.197291:qcrypto_tls_cipher_suite_info data:[0x00, 0x9d] version:TLS1.2 name:TLS_RSA_AES_256_GCM_SHA384
  1590664444.197296:qcrypto_tls_cipher_suite_info data:[0xc0, 0x9d] version:TLS1.2 name:TLS_RSA_AES_256_CCM
  1590664444.197300:qcrypto_tls_cipher_suite_info data:[0x00, 0x35] version:TLS1.0 name:TLS_RSA_AES_256_CBC_SHA1
  1590664444.197304:qcrypto_tls_cipher_suite_info data:[0x00, 0x9c] version:TLS1.2 name:TLS_RSA_AES_128_GCM_SHA256
  1590664444.197308:qcrypto_tls_cipher_suite_info data:[0xc0, 0x9c] version:TLS1.2 name:TLS_RSA_AES_128_CCM
  1590664444.197312:qcrypto_tls_cipher_suite_info data:[0x00, 0x2f] version:TLS1.0 name:TLS_RSA_AES_128_CBC_SHA1
  1590664444.197316:qcrypto_tls_cipher_suite_info data:[0x00, 0x9f] version:TLS1.2 name:TLS_DHE_RSA_AES_256_GCM_SHA384
  1590664444.197320:qcrypto_tls_cipher_suite_info data:[0xcc, 0xaa] version:TLS1.2 name:TLS_DHE_RSA_CHACHA20_POLY1305
  1590664444.197325:qcrypto_tls_cipher_suite_info data:[0xc0, 0x9f] version:TLS1.2 name:TLS_DHE_RSA_AES_256_CCM
  1590664444.197329:qcrypto_tls_cipher_suite_info data:[0x00, 0x39] version:TLS1.0 name:TLS_DHE_RSA_AES_256_CBC_SHA1
  1590664444.197333:qcrypto_tls_cipher_suite_info data:[0x00, 0x9e] version:TLS1.2 name:TLS_DHE_RSA_AES_128_GCM_SHA256
  1590664444.197337:qcrypto_tls_cipher_suite_info data:[0xc0, 0x9e] version:TLS1.2 name:TLS_DHE_RSA_AES_128_CCM
  1590664444.197341:qcrypto_tls_cipher_suite_info data:[0x00, 0x33] version:TLS1.0 name:TLS_DHE_RSA_AES_128_CBC_SHA1
  1590664444.197345:qcrypto_tls_cipher_suite_count count: 29

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
v7:
- Use Laszlo's loop with enum mode (lersek)
- Convert debug printf to trace events (danpb)
- Use buildsys CONFIG_GNUTLS instead of C ifdef'ry (danpb)
---
 include/crypto/tls-cipher-suites.h |  38 +++++++++
 crypto/tls-cipher-suites.c         | 127 +++++++++++++++++++++++++++++
 crypto/Makefile.objs               |   1 +
 crypto/trace-events                |   5 ++
 4 files changed, 171 insertions(+)
 create mode 100644 include/crypto/tls-cipher-suites.h
 create mode 100644 crypto/tls-cipher-suites.c

diff --git a/include/crypto/tls-cipher-suites.h b/include/crypto/tls-cipher-suites.h
new file mode 100644
index 0000000000..20a7c74edf
--- /dev/null
+++ b/include/crypto/tls-cipher-suites.h
@@ -0,0 +1,38 @@
+/*
+ * QEMU TLS Cipher Suites
+ *
+ * Copyright (c) 2019 Red Hat, Inc.
+ *
+ * Author: Philippe Mathieu-Daudé <philmd@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#ifndef QCRYPTO_TLSCIPHERSUITES_H
+#define QCRYPTO_TLSCIPHERSUITES_H
+
+#include "qom/object.h"
+#include "crypto/tlscreds.h"
+
+#define TYPE_QCRYPTO_TLS_CIPHER_SUITES "tls-cipher-suites"
+#define QCRYPTO_TLS_CIPHER_SUITES(obj) \
+    OBJECT_CHECK(QCryptoTLSCipherSuites, (obj), TYPE_QCRYPTO_TLS_CIPHER_SUITES)
+
+/*
+ * IANA registered TLS ciphers:
+ * https://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml#tls-parameters-4
+ */
+typedef struct {
+    uint8_t data[2];
+} QEMU_PACKED IANA_TLS_CIPHER;
+
+typedef struct QCryptoTLSCipherSuites {
+    /* <private> */
+    QCryptoTLSCreds parent_obj;
+
+    /* <public> */
+    IANA_TLS_CIPHER *cipher_list;
+    unsigned cipher_count;
+} QCryptoTLSCipherSuites;
+
+#endif /* QCRYPTO_TLSCIPHERSUITES_H */
diff --git a/crypto/tls-cipher-suites.c b/crypto/tls-cipher-suites.c
new file mode 100644
index 0000000000..f02a041f9a
--- /dev/null
+++ b/crypto/tls-cipher-suites.c
@@ -0,0 +1,127 @@
+/*
+ * QEMU TLS Cipher Suites
+ *
+ * Copyright (c) 2019 Red Hat, Inc.
+ *
+ * Author: Philippe Mathieu-Daudé <philmd@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "qom/object_interfaces.h"
+#include "qemu/error-report.h"
+#include "crypto/tlscreds.h"
+#include "crypto/tls-cipher-suites.h"
+#include "trace.h"
+
+static void parse_cipher_suites(QCryptoTLSCipherSuites *s,
+                                const char *priority_name, Error **errp)
+{
+    int ret;
+    const char *err;
+    gnutls_priority_t pcache;
+    enum { M_ENUMERATE, M_GENERATE, M_DONE } mode;
+
+    assert(priority_name);
+    trace_qcrypto_tls_cipher_suite_priority(priority_name);
+    ret = gnutls_priority_init(&pcache, priority_name, &err);
+    if (ret < 0) {
+        error_setg(errp, "Syntax error using priority '%s': %s",
+                   priority_name, gnutls_strerror(ret));
+        return;
+    }
+
+    for (mode = M_ENUMERATE; mode < M_DONE; mode++) {
+        size_t i;
+
+        for (i = 0;; i++) {
+            int ret;
+            unsigned idx;
+            const char *name;
+            IANA_TLS_CIPHER cipher;
+            gnutls_protocol_t protocol;
+
+            ret = gnutls_priority_get_cipher_suite_index(pcache, i, &idx);
+            if (ret == GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE) {
+                break;
+            }
+            if (ret == GNUTLS_E_UNKNOWN_CIPHER_SUITE) {
+                continue;
+            }
+
+            name = gnutls_cipher_suite_info(idx, (unsigned char *)&cipher,
+                                            NULL, NULL, NULL, &protocol);
+            if (name == NULL) {
+                continue;
+            }
+
+            if (mode == M_GENERATE) {
+                const char *version;
+
+                version = gnutls_protocol_get_name(protocol);
+                trace_qcrypto_tls_cipher_suite_info(cipher.data[0],
+                                                    cipher.data[1],
+                                                    version, name);
+                s->cipher_list[s->cipher_count] = cipher;
+            }
+            s->cipher_count++;
+        }
+
+        if (mode == M_ENUMERATE) {
+            if (s->cipher_count == 0) {
+                break;
+            }
+            s->cipher_list = g_new(IANA_TLS_CIPHER, s->cipher_count);
+            s->cipher_count = 0;
+        }
+    }
+    trace_qcrypto_tls_cipher_suite_count(s->cipher_count);
+    gnutls_priority_deinit(pcache);
+}
+
+static void qcrypto_tls_cipher_suites_complete(UserCreatable *uc, Error **errp)
+{
+    QCryptoTLSCreds *s = QCRYPTO_TLS_CREDS(uc);
+
+    if (!s->priority) {
+        error_setg(errp, "'priority' property is not set");
+        return;
+    }
+    parse_cipher_suites(QCRYPTO_TLS_CIPHER_SUITES(s), s->priority, errp);
+}
+
+static void qcrypto_tls_cipher_suites_finalize(Object *obj)
+{
+    QCryptoTLSCipherSuites *s = QCRYPTO_TLS_CIPHER_SUITES(obj);
+
+    g_free(s->cipher_list);
+}
+
+static void qcrypto_tls_cipher_suites_class_init(ObjectClass *oc, void *data)
+{
+    UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
+
+    ucc->complete = qcrypto_tls_cipher_suites_complete;
+}
+
+static const TypeInfo qcrypto_tls_cipher_suites_info = {
+    .parent = TYPE_QCRYPTO_TLS_CREDS,
+    .name = TYPE_QCRYPTO_TLS_CIPHER_SUITES,
+    .instance_size = sizeof(QCryptoTLSCipherSuites),
+    .instance_finalize = qcrypto_tls_cipher_suites_finalize,
+    .class_size = sizeof(QCryptoTLSCredsClass),
+    .class_init = qcrypto_tls_cipher_suites_class_init,
+    .interfaces = (InterfaceInfo[]) {
+        { TYPE_USER_CREATABLE },
+        { }
+    }
+};
+
+static void qcrypto_tls_cipher_suites_register_types(void)
+{
+    type_register_static(&qcrypto_tls_cipher_suites_info);
+}
+
+type_init(qcrypto_tls_cipher_suites_register_types);
diff --git a/crypto/Makefile.objs b/crypto/Makefile.objs
index c2a371b0b4..1c1b5e21ff 100644
--- a/crypto/Makefile.objs
+++ b/crypto/Makefile.objs
@@ -13,6 +13,7 @@ crypto-obj-y += cipher.o
 crypto-obj-$(CONFIG_AF_ALG) += afalg.o
 crypto-obj-$(CONFIG_AF_ALG) += cipher-afalg.o
 crypto-obj-$(CONFIG_AF_ALG) += hash-afalg.o
+crypto-obj-$(CONFIG_GNUTLS) += tls-cipher-suites.o
 crypto-obj-y += tlscreds.o
 crypto-obj-y += tlscredsanon.o
 crypto-obj-y += tlscredspsk.o
diff --git a/crypto/trace-events b/crypto/trace-events
index 9e594d30e8..c07a752b50 100644
--- a/crypto/trace-events
+++ b/crypto/trace-events
@@ -21,3 +21,8 @@ qcrypto_tls_creds_x509_load_cert_list(void *creds, const char *file) "TLS creds
 # tlssession.c
 qcrypto_tls_session_new(void *session, void *creds, const char *hostname, const char *authzid, int endpoint) "TLS session new session=%p creds=%p hostname=%s authzid=%s endpoint=%d"
 qcrypto_tls_session_check_creds(void *session, const char *status) "TLS session check creds session=%p status=%s"
+
+# tls-cipher-suites.c
+qcrypto_tls_cipher_suite_priority(const char *name) "priority: %s"
+qcrypto_tls_cipher_suite_info(uint8_t data0, uint8_t data1, const char *version, const char *name) "data:[0x%02x, 0x%02x] version:%s name:%s"
+qcrypto_tls_cipher_suite_count(unsigned count) "count: %u"
-- 
2.21.3