Crypto patches

* Drop unused 'detached-header' QAPI field from LUKS create options
 * Improve tracing of TLS sockets and TLS chardevs
 * Improve error messages from TLS I/O failures
 * Add docs about use of LUKS detached header options
 * Allow building without libtasn1, but with GNUTLS
 * Fix detection of libgcrypt when libgcrypt-config is absent
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Merge tag 'misc-fixes-pull-request' of https://gitlab.com/berrange/qemu into staging

Crypto patches

* Drop unused 'detached-header' QAPI field from LUKS create options
* Improve tracing of TLS sockets and TLS chardevs
* Improve error messages from TLS I/O failures
* Add docs about use of LUKS detached header options
* Allow building without libtasn1, but with GNUTLS
* Fix detection of libgcrypt when libgcrypt-config is absent

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# gpg: Signature made Wed 24 Jul 2024 07:46:29 PM AEST
# gpg:                using RSA key DAF3A6FDB26B62912D0E8E3FBE86EBB415104FDF
# gpg: Good signature from "Daniel P. Berrange <dan@berrange.com>" [full]
# gpg:                 aka "Daniel P. Berrange <berrange@redhat.com>" [full]

* tag 'misc-fixes-pull-request' of https://gitlab.com/berrange/qemu:
  crypto: propagate errors from TLS session I/O callbacks
  crypto: push error reporting into TLS session I/O APIs
  crypto: drop gnutls debug logging support
  chardev: add tracing of socket error conditions
  meson: build chardev trace files when have_block
  qapi: drop unused QCryptoBlockCreateOptionsLUKS.detached-header
  meson.build: fix libgcrypt detection on system without libgcrypt-config
  docs/devel: Add introduction to LUKS volume with detached header
  crypto: Allow building with GnuTLS but without Libtasn1
  crypto: Restrict pkix_asn1_tab[] to crypto-tls-x509-helpers.c
  crypto: Remove 'crypto-tls-x509-helpers.h' from crypto-tls-psk-helpers.c

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

MAINTAINERS

@@ -3451,6 +3451,7 @@ Detached LUKS header
 M: Hyman Huang <yong.huang@smartx.com>
 S: Maintained
 F: tests/qemu-iotests/tests/luks-detached-header
+F: docs/devel/luks-detached-header.rst
 
 D-Bus
 M: Marc-André Lureau <marcandre.lureau@redhat.com>
@@ -3484,7 +3485,7 @@ F: qapi/crypto.json
 F: tests/unit/test-crypto-*
 F: tests/bench/benchmark-crypto-*
 F: tests/unit/crypto-tls-*
-F: tests/unit/pkix_asn1_tab.c
+F: tests/unit/pkix_asn1_tab.c.inc
 F: qemu.sasl
 
 Coroutines

chardev/char-socket.c

@@ -33,6 +33,7 @@
 #include "qapi/clone-visitor.h"
 #include "qapi/qapi-visit-sockets.h"
 #include "qemu/yank.h"
+#include "trace.h"
 
 #include "chardev/char-io.h"
 #include "chardev/char-socket.h"
@@ -126,6 +127,7 @@ static int tcp_chr_write(Chardev *chr, const uint8_t *buf, int len)
         if (ret < 0 && errno != EAGAIN) {
             if (tcp_chr_read_poll(chr) <= 0) {
                 /* Perform disconnect and return error. */
+                trace_chr_socket_poll_err(chr, chr->label);
                 tcp_chr_disconnect_locked(chr);
             } /* else let the read handler finish it properly */
         }
@@ -279,15 +281,16 @@ static ssize_t tcp_chr_recv(Chardev *chr, char *buf, size_t len)
     size_t i;
     int *msgfds = NULL;
     size_t msgfds_num = 0;
+    Error *err = NULL;
 
     if (qio_channel_has_feature(s->ioc, QIO_CHANNEL_FEATURE_FD_PASS)) {
         ret = qio_channel_readv_full(s->ioc, &iov, 1,
                                      &msgfds, &msgfds_num,
-                                     0, NULL);
+                                     0, &err);
     } else {
         ret = qio_channel_readv_full(s->ioc, &iov, 1,
                                      NULL, NULL,
-                                     0, NULL);
+                                     0, &err);
     }
 
     if (msgfds_num) {
@@ -322,7 +325,11 @@ static ssize_t tcp_chr_recv(Chardev *chr, char *buf, size_t len)
         errno = EAGAIN;
         ret = -1;
     } else if (ret == -1) {
+        trace_chr_socket_recv_err(chr, chr->label, error_get_pretty(err));
+        error_free(err);
         errno = EIO;
+    } else if (ret == 0) {
+        trace_chr_socket_recv_eof(chr, chr->label);
     }
 
     return ret;
@@ -463,6 +470,7 @@ static void tcp_chr_disconnect_locked(Chardev *chr)
     SocketChardev *s = SOCKET_CHARDEV(chr);
     bool emit_close = s->state == TCP_CHARDEV_STATE_CONNECTED;
 
+    trace_chr_socket_disconnect(chr, chr->label);
     tcp_chr_free_connection(chr);
 
     if (s->listener) {
@@ -521,6 +529,7 @@ static gboolean tcp_chr_hup(QIOChannel *channel,
                                void *opaque)
 {
     Chardev *chr = CHARDEV(opaque);
+    trace_chr_socket_hangup(chr, chr->label);
     tcp_chr_disconnect(chr);
     return G_SOURCE_REMOVE;
 }
@@ -672,15 +681,18 @@ static gboolean tcp_chr_telnet_init_io(QIOChannel *ioc,
     SocketChardev *s = user_data;
     Chardev *chr = CHARDEV(s);
     TCPChardevTelnetInit *init = s->telnet_init;
+    Error *err = NULL;
     ssize_t ret;
 
     assert(init);
 
-    ret = qio_channel_write(ioc, init->buf, init->buflen, NULL);
+    ret = qio_channel_write(ioc, init->buf, init->buflen, &err);
     if (ret < 0) {
         if (ret == QIO_CHANNEL_ERR_BLOCK) {
             ret = 0;
         } else {
+            trace_chr_socket_write_err(chr, chr->label, error_get_pretty(err));
+            error_free(err);
             tcp_chr_disconnect(chr);
             goto end;
         }
@@ -765,9 +777,9 @@ static void tcp_chr_websock_handshake(QIOTask *task, gpointer user_data)
     Error *err = NULL;
 
     if (qio_task_propagate_error(task, &err)) {
-        error_reportf_err(err,
+        trace_chr_socket_ws_handshake_err(chr, chr->label,
-                          "websock handshake of character device %s failed: ",
+                                          error_get_pretty(err));
-                          chr->label);
+        error_free(err);
         tcp_chr_disconnect(chr);
     } else {
         if (s->do_telnetopt) {
@@ -805,9 +817,9 @@ static void tcp_chr_tls_handshake(QIOTask *task,
     Error *err = NULL;
 
     if (qio_task_propagate_error(task, &err)) {
-        error_reportf_err(err,
+        trace_chr_socket_tls_handshake_err(chr, chr->label,
-                          "TLS handshake of character device %s failed: ",
+                                           error_get_pretty(err));
-                          chr->label);
+        error_free(err);
         tcp_chr_disconnect(chr);
     } else {
         if (s->is_websock) {
@@ -826,19 +838,22 @@ static void tcp_chr_tls_init(Chardev *chr)
     SocketChardev *s = SOCKET_CHARDEV(chr);
     QIOChannelTLS *tioc;
     gchar *name;
+    Error *err = NULL;
 
     if (s->is_listen) {
         tioc = qio_channel_tls_new_server(
             s->ioc, s->tls_creds,
             s->tls_authz,
-            NULL);
+            &err);
     } else {
         tioc = qio_channel_tls_new_client(
             s->ioc, s->tls_creds,
             s->addr->u.inet.host,
-            NULL);
+            &err);
     }
     if (tioc == NULL) {
+        trace_chr_socket_tls_init_err(chr, chr->label, error_get_pretty(err));
+        error_free(err);
         tcp_chr_disconnect(chr);
         return;
     }

chardev/trace-events

@@ -17,3 +17,13 @@ spice_vmc_register_interface(void *scd) "spice vmc registered interface %p"
 spice_vmc_unregister_interface(void *scd) "spice vmc unregistered interface %p"
 spice_vmc_event(int event) "spice vmc event %d"
 
+# char-socket.c
+chr_socket_poll_err(void *chrdev, const char *label) "chardev socket poll error %p (%s)"
+chr_socket_recv_err(void *chrdev, const char *label, const char *err) "chardev socket recv error %p (%s): %s"
+chr_socket_recv_eof(void *chrdev, const char *label) "chardev socket recv end-of-file %p (%s)"
+chr_socket_write_err(void *chrdev, const char *label, const char *err) "chardev socket write error %p (%s): %s"
+chr_socket_disconnect(void *chrdev, const char *label) "chardev socket disconnect %p (%s)"
+chr_socket_hangup(void *chrdev, const char *label) "chardev socket hangup %p (%s)"
+chr_socket_ws_handshake_err(void *chrdev, const char *label, const char *err) "chardev socket websock handshake error %p (%s): %s"
+chr_socket_tls_handshake_err(void *chrdev, const char *label, const char *err) "chardev socket TLS handshake error %p (%s): %s"
+chr_socket_tls_init_err(void *chrdev, const char *label, const char *err) "chardev socket TLS init error %p (%s): %s"

crypto/init.c

@@ -34,14 +34,11 @@
 
 #include "crypto/random.h"
 
-/* #define DEBUG_GNUTLS */
-#ifdef DEBUG_GNUTLS
-static void qcrypto_gnutls_log(int level, const char *str)
-{
-    fprintf(stderr, "%d: %s", level, str);
-}
-#endif
 
+/*
+ * To debug GNUTLS see env vars listed in
+ * https://gnutls.org/manual/html_node/Debugging-and-auditing.html
+ */
 int qcrypto_init(Error **errp)
 {
 #ifdef CONFIG_GNUTLS
@@ -53,10 +50,6 @@ int qcrypto_init(Error **errp)
                    gnutls_strerror(ret));
         return -1;
     }
-#ifdef DEBUG_GNUTLS
-    gnutls_global_set_log_level(10);
-    gnutls_global_set_log_function(qcrypto_gnutls_log);
-#endif
 #endif
 
 #ifdef CONFIG_GCRYPT

crypto/tlssession.c

@@ -44,6 +44,13 @@ struct QCryptoTLSSession {
     QCryptoTLSSessionReadFunc readFunc;
     void *opaque;
     char *peername;
+
+    /*
+     * Allow concurrent reads and writes, so track
+     * errors separately
+     */
+    Error *rerr;
+    Error *werr;
 };
 
 
@@ -54,6 +61,9 @@ qcrypto_tls_session_free(QCryptoTLSSession *session)
         return;
     }
 
+    error_free(session->rerr);
+    error_free(session->werr);
+
     gnutls_deinit(session->handle);
     g_free(session->hostname);
     g_free(session->peername);
@@ -67,13 +77,26 @@ static ssize_t
 qcrypto_tls_session_push(void *opaque, const void *buf, size_t len)
 {
     QCryptoTLSSession *session = opaque;
+    ssize_t ret;
 
     if (!session->writeFunc) {
         errno = EIO;
         return -1;
     };
 
-    return session->writeFunc(buf, len, session->opaque);
+    error_free(session->werr);
+    session->werr = NULL;
+
+    ret = session->writeFunc(buf, len, session->opaque, &session->werr);
+    if (ret == QCRYPTO_TLS_SESSION_ERR_BLOCK) {
+        errno = EAGAIN;
+        return -1;
+    } else if (ret < 0) {
+        errno = EIO;
+        return -1;
+    } else {
+        return ret;
+    }
 }
 
 
@@ -81,13 +104,26 @@ static ssize_t
 qcrypto_tls_session_pull(void *opaque, void *buf, size_t len)
 {
     QCryptoTLSSession *session = opaque;
+    ssize_t ret;
 
     if (!session->readFunc) {
         errno = EIO;
         return -1;
     };
 
-    return session->readFunc(buf, len, session->opaque);
+    error_free(session->rerr);
+    session->rerr = NULL;
+
+    ret = session->readFunc(buf, len, session->opaque, &session->rerr);
+    if (ret == QCRYPTO_TLS_SESSION_ERR_BLOCK) {
+        errno = EAGAIN;
+        return -1;
+    } else if (ret < 0) {
+        errno = EIO;
+        return -1;
+    } else {
+        return ret;
+    }
 }
 
 #define TLS_PRIORITY_ADDITIONAL_ANON "+ANON-DH"
@@ -441,23 +477,25 @@ qcrypto_tls_session_set_callbacks(QCryptoTLSSession *session,
 ssize_t
 qcrypto_tls_session_write(QCryptoTLSSession *session,
                           const char *buf,
-                          size_t len)
+                          size_t len,
+                          Error **errp)
 {
     ssize_t ret = gnutls_record_send(session->handle, buf, len);
 
     if (ret < 0) {
-        switch (ret) {
+        if (ret == GNUTLS_E_AGAIN) {
-        case GNUTLS_E_AGAIN:
+            return QCRYPTO_TLS_SESSION_ERR_BLOCK;
-            errno = EAGAIN;
+        } else {
-            break;
+            if (session->werr) {
-        case GNUTLS_E_INTERRUPTED:
+                error_propagate(errp, session->werr);
-            errno = EINTR;
+                session->werr = NULL;
-            break;
+            } else {
-        default:
+                error_setg(errp,
-            errno = EIO;
+                           "Cannot write to TLS channel: %s",
-            break;
+                           gnutls_strerror(ret));
+            }
+            return -1;
         }
-        ret = -1;
     }
 
     return ret;
@@ -467,26 +505,29 @@ qcrypto_tls_session_write(QCryptoTLSSession *session,
 ssize_t
 qcrypto_tls_session_read(QCryptoTLSSession *session,
                          char *buf,
-                         size_t len)
+                         size_t len,
+                         bool gracefulTermination,
+                         Error **errp)
 {
     ssize_t ret = gnutls_record_recv(session->handle, buf, len);
 
     if (ret < 0) {
-        switch (ret) {
+        if (ret == GNUTLS_E_AGAIN) {
-        case GNUTLS_E_AGAIN:
+            return QCRYPTO_TLS_SESSION_ERR_BLOCK;
-            errno = EAGAIN;
+        } else if ((ret == GNUTLS_E_PREMATURE_TERMINATION) &&
-            break;
+                   gracefulTermination){
-        case GNUTLS_E_INTERRUPTED:
+            return 0;
-            errno = EINTR;
+        } else {
-            break;
+            if (session->rerr) {
-        case GNUTLS_E_PREMATURE_TERMINATION:
+                error_propagate(errp, session->rerr);
-            errno = ECONNABORTED;
+                session->rerr = NULL;
-            break;
+            } else {
-        default:
+                error_setg(errp,
-            errno = EIO;
+                           "Cannot read from TLS channel: %s",
-            break;
+                           gnutls_strerror(ret));
+            }
+            return -1;
         }
-        ret = -1;
     }
 
     return ret;
@@ -512,11 +553,21 @@ qcrypto_tls_session_handshake(QCryptoTLSSession *session,
             ret == GNUTLS_E_AGAIN) {
             ret = 1;
         } else {
-            error_setg(errp, "TLS handshake failed: %s",
+            if (session->rerr || session->werr) {
-                       gnutls_strerror(ret));
+                error_setg(errp, "TLS handshake failed: %s: %s",
+                           gnutls_strerror(ret),
+                           error_get_pretty(session->rerr ?
+                                            session->rerr : session->werr));
+            } else {
+                error_setg(errp, "TLS handshake failed: %s",
+                           gnutls_strerror(ret));
+            }
             ret = -1;
         }
     }
+    error_free(session->rerr);
+    error_free(session->werr);
+    session->rerr = session->werr = NULL;
 
     return ret;
 }
@@ -605,9 +656,10 @@ qcrypto_tls_session_set_callbacks(
 ssize_t
 qcrypto_tls_session_write(QCryptoTLSSession *sess,
                           const char *buf,
-                          size_t len)
+                          size_t len,
+                          Error **errp)
 {
-    errno = -EIO;
+    error_setg(errp, "TLS requires GNUTLS support");
     return -1;
 }
 
@@ -615,9 +667,11 @@ qcrypto_tls_session_write(QCryptoTLSSession *sess,
 ssize_t
 qcrypto_tls_session_read(QCryptoTLSSession *sess,
                          char *buf,
-                         size_t len)
+                         size_t len,
+                         bool gracefulTermination,
+                         Error **errp)
 {
-    errno = -EIO;
+    error_setg(errp, "TLS requires GNUTLS support");
     return -1;
 }
 

docs/devel/crypto.rst

@@ -0,0 +1,10 @@
+.. _crypto-ref:
+
+====================
+Cryptography in QEMU
+====================
+
+.. toctree::
+   :maxdepth: 2
+
+   luks-detached-header

docs/devel/index-internals.rst

@@ -20,3 +20,4 @@ Details about QEMU's various subsystems including how to add features to them.
    vfio-iommufd
    writing-monitor-commands
    virtio-backends
+   crypto

docs/devel/luks-detached-header.rst

@@ -0,0 +1,182 @@
+================================
+LUKS volume with detached header
+================================
+
+Introduction
+============
+
+This document gives an overview of the design of LUKS volume with detached
+header and how to use it.
+
+Background
+==========
+
+The LUKS format has ability to store the header in a separate volume from
+the payload. We could extend the LUKS driver in QEMU to support this use
+case.
+
+Normally a LUKS volume has a layout:
+
+::
+
+         +-----------------------------------------------+
+         |         |                |                    |
+ disk    | header  |  key material  |  disk payload data |
+         |         |                |                    |
+         +-----------------------------------------------+
+
+With a detached LUKS header, you need 2 disks so getting:
+
+::
+
+         +--------------------------+
+ disk1   |   header  | key material |
+         +--------------------------+
+         +---------------------+
+ disk2   |  disk payload data  |
+         +---------------------+
+
+There are a variety of benefits to doing this:
+
+ * Secrecy - the disk2 cannot be identified as containing LUKS
+             volume since there's no header
+ * Control - if access to the disk1 is restricted, then even
+             if someone has access to disk2 they can't unlock
+             it. Might be useful if you have disks on NFS but
+             want to restrict which host can launch a VM
+             instance from it, by dynamically providing access
+             to the header to a designated host
+ * Flexibility - your application data volume may be a given
+                 size and it is inconvenient to resize it to
+                 add encryption.You can store the LUKS header
+                 separately and use the existing storage
+                 volume for payload
+ * Recovery - corruption of a bit in the header may make the
+              entire payload inaccessible. It might be
+              convenient to take backups of the header. If
+              your primary disk header becomes corrupt, you
+              can unlock the data still by pointing to the
+              backup detached header
+
+Architecture
+============
+
+Take the qcow2 encryption, for example. The architecture of the
+LUKS volume with detached header is shown in the diagram below.
+
+There are two children of the root node: a file and a header.
+Data from the disk payload is stored in the file node. The
+LUKS header and key material are located in the header node,
+as previously mentioned.
+
+::
+
+                       +-----------------------------+
+  Root node            |          foo[luks]          |
+                       +-----------------------------+
+                          |                       |
+                     file |                header |
+                          |                       |
+               +---------------------+    +------------------+
+  Child node   |payload-format[qcow2]|    |header-format[raw]|
+               +---------------------+    +------------------+
+                          |                       |
+                     file |                 file  |
+                          |                       |
+               +----------------------+  +---------------------+
+  Child node   |payload-protocol[file]|  |header-protocol[file]|
+               +----------------------+  +---------------------+
+                          |                       |
+                          |                       |
+                          |                       |
+                     Host storage            Host storage
+
+Usage
+=====
+
+Create a LUKS disk with a detached header using qemu-img
+--------------------------------------------------------
+
+Shell commandline::
+
+  # qemu-img create --object secret,id=sec0,data=abc123 -f luks \
+    -o cipher-alg=aes-256,cipher-mode=xts -o key-secret=sec0 \
+    -o detached-header=true test-header.img
+  # qemu-img create -f qcow2 test-payload.qcow2 200G
+  # qemu-img info 'json:{"driver":"luks","file":{"filename": \
+    "test-payload.img"},"header":{"filename":"test-header.img"}}'
+
+Set up a VM's LUKS volume with a detached header
+------------------------------------------------
+
+Qemu commandline::
+
+  # qemu-system-x86_64 ... \
+    -object '{"qom-type":"secret","id":"libvirt-3-format-secret", \
+    "data":"abc123"}' \
+    -blockdev '{"driver":"file","filename":"/path/to/test-header.img", \
+    "node-name":"libvirt-1-storage"}' \
+    -blockdev '{"node-name":"libvirt-1-format","read-only":false, \
+    "driver":"raw","file":"libvirt-1-storage"}' \
+    -blockdev '{"driver":"file","filename":"/path/to/test-payload.qcow2", \
+    "node-name":"libvirt-2-storage"}' \
+    -blockdev '{"node-name":"libvirt-2-format","read-only":false, \
+    "driver":"qcow2","file":"libvirt-2-storage"}' \
+    -blockdev '{"node-name":"libvirt-3-format","driver":"luks", \
+    "file":"libvirt-2-format","header":"libvirt-1-format","key-secret": \
+    "libvirt-3-format-secret"}' \
+    -device '{"driver":"virtio-blk-pci","bus":XXX,"addr":YYY,"drive": \
+    "libvirt-3-format","id":"virtio-disk1"}'
+
+Add LUKS volume to a VM with a detached header
+----------------------------------------------
+
+1. object-add the secret for decrypting the cipher stored in
+   LUKS header above::
+
+    # virsh qemu-monitor-command vm '{"execute":"object-add", \
+      "arguments":{"qom-type":"secret", "id": \
+      "libvirt-4-format-secret", "data":"abc123"}}'
+
+2. block-add the protocol node for LUKS header::
+
+    # virsh qemu-monitor-command vm '{"execute":"blockdev-add", \
+      "arguments":{"node-name":"libvirt-1-storage", "driver":"file", \
+      "filename": "/path/to/test-header.img" }}'
+
+3. block-add the raw-drived node for LUKS header::
+
+    # virsh qemu-monitor-command vm '{"execute":"blockdev-add", \
+      "arguments":{"node-name":"libvirt-1-format", "driver":"raw", \
+      "file":"libvirt-1-storage"}}'
+
+4. block-add the protocol node for disk payload image::
+
+    # virsh qemu-monitor-command vm '{"execute":"blockdev-add", \
+      "arguments":{"node-name":"libvirt-2-storage", "driver":"file", \
+      "filename":"/path/to/test-payload.qcow2"}}'
+
+5. block-add the qcow2-drived format node for disk payload data::
+
+    # virsh qemu-monitor-command vm '{"execute":"blockdev-add", \
+      "arguments":{"node-name":"libvirt-2-format", "driver":"qcow2", \
+      "file":"libvirt-2-storage"}}'
+
+6. block-add the luks-drived format node to link the qcow2 disk
+   with the LUKS header by specifying the field "header"::
+
+    # virsh qemu-monitor-command vm '{"execute":"blockdev-add", \
+      "arguments":{"node-name":"libvirt-3-format", "driver":"luks", \
+      "file":"libvirt-2-format", "header":"libvirt-1-format", \
+      "key-secret":"libvirt-2-format-secret"}}'
+
+7. hot-plug the virtio-blk device finally::
+
+    # virsh qemu-monitor-command vm '{"execute":"device_add", \
+      "arguments": {"driver":"virtio-blk-pci", \
+      "drive": "libvirt-3-format", "id":"virtio-disk2"}}
+
+TODO
+====
+
+1. Support the shared detached LUKS header within the VM.

include/crypto/tlssession.h

@@ -107,6 +107,7 @@
 
 typedef struct QCryptoTLSSession QCryptoTLSSession;
 
+#define QCRYPTO_TLS_SESSION_ERR_BLOCK -2
 
 /**
  * qcrypto_tls_session_new:
@@ -177,12 +178,18 @@ G_DEFINE_AUTOPTR_CLEANUP_FUNC(QCryptoTLSSession, qcrypto_tls_session_free)
 int qcrypto_tls_session_check_credentials(QCryptoTLSSession *sess,
                                           Error **errp);
 
+/*
+ * These must return QCRYPTO_TLS_SESSION_ERR_BLOCK if the I/O
+ * would block, but on other errors, must fill 'errp'
+ */
 typedef ssize_t (*QCryptoTLSSessionWriteFunc)(const char *buf,
                                               size_t len,
-                                              void *opaque);
+                                              void *opaque,
+                                              Error **errp);
 typedef ssize_t (*QCryptoTLSSessionReadFunc)(char *buf,
                                              size_t len,
-                                             void *opaque);
+                                             void *opaque,
+                                             Error **errp);
 
 /**
  * qcrypto_tls_session_set_callbacks:
@@ -212,6 +219,7 @@ void qcrypto_tls_session_set_callbacks(QCryptoTLSSession *sess,
  * @sess: the TLS session object
  * @buf: the plain text to send
  * @len: the length of @buf
+ * @errp: pointer to hold returned error object
  *
  * Encrypt @len bytes of the data in @buf and send
  * it to the remote peer using the callback previously
@@ -221,32 +229,45 @@ void qcrypto_tls_session_set_callbacks(QCryptoTLSSession *sess,
  * qcrypto_tls_session_get_handshake_status() returns
  * QCRYPTO_TLS_HANDSHAKE_COMPLETE
  *
- * Returns: the number of bytes sent, or -1 on error
+ * Returns: the number of bytes sent,
+ * or QCRYPTO_TLS_SESSION_ERR_BLOCK if the write would block,
+ * or -1 on error.
  */
 ssize_t qcrypto_tls_session_write(QCryptoTLSSession *sess,
                                   const char *buf,
-                                  size_t len);
+                                  size_t len,
+                                  Error **errp);
 
 /**
  * qcrypto_tls_session_read:
  * @sess: the TLS session object
  * @buf: to fill with plain text received
  * @len: the length of @buf
+ * @gracefulTermination: treat premature termination as graceful EOF
+ * @errp: pointer to hold returned error object
  *
  * Receive up to @len bytes of data from the remote peer
  * using the callback previously registered with
  * qcrypto_tls_session_set_callbacks(), decrypt it and
  * store it in @buf.
  *
+ * If @gracefulTermination is true, then a premature termination
+ * of the TLS session will be treated as indicating EOF, as
+ * opposed to an error.
+ *
  * It is an error to call this before
  * qcrypto_tls_session_get_handshake_status() returns
  * QCRYPTO_TLS_HANDSHAKE_COMPLETE
  *
- * Returns: the number of bytes received, or -1 on error
+ * Returns: the number of bytes received,
+ * or QCRYPTO_TLS_SESSION_ERR_BLOCK if the receive would block,
+ * or -1 on error.
  */
 ssize_t qcrypto_tls_session_read(QCryptoTLSSession *sess,
                                  char *buf,
-                                 size_t len);
+                                 size_t len,
+                                 bool gracefulTermination,
+                                 Error **errp);
 
 /**
  * qcrypto_tls_session_check_pending:

io/channel-tls.c

@@ -28,17 +28,16 @@
 
 static ssize_t qio_channel_tls_write_handler(const char *buf,
                                              size_t len,
-                                             void *opaque)
+                                             void *opaque,
+                                             Error **errp)
 {
     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(opaque);
     ssize_t ret;
 
-    ret = qio_channel_write(tioc->master, buf, len, NULL);
+    ret = qio_channel_write(tioc->master, buf, len, errp);
     if (ret == QIO_CHANNEL_ERR_BLOCK) {
-        errno = EAGAIN;
+        return QCRYPTO_TLS_SESSION_ERR_BLOCK;
-        return -1;
     } else if (ret < 0) {
-        errno = EIO;
         return -1;
     }
     return ret;
@@ -46,17 +45,16 @@ static ssize_t qio_channel_tls_write_handler(const char *buf,
 
 static ssize_t qio_channel_tls_read_handler(char *buf,
                                             size_t len,
-                                            void *opaque)
+                                            void *opaque,
+                                            Error **errp)
 {
     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(opaque);
     ssize_t ret;
 
-    ret = qio_channel_read(tioc->master, buf, len, NULL);
+    ret = qio_channel_read(tioc->master, buf, len, errp);
     if (ret == QIO_CHANNEL_ERR_BLOCK) {
-        errno = EAGAIN;
+        return QCRYPTO_TLS_SESSION_ERR_BLOCK;
-        return -1;
     } else if (ret < 0) {
-        errno = EIO;
         return -1;
     }
     return ret;
@@ -277,24 +275,19 @@ static ssize_t qio_channel_tls_readv(QIOChannel *ioc,
     ssize_t got = 0;
 
     for (i = 0 ; i < niov ; i++) {
-        ssize_t ret = qcrypto_tls_session_read(tioc->session,
+        ssize_t ret = qcrypto_tls_session_read(
-                                               iov[i].iov_base,
+            tioc->session,
-                                               iov[i].iov_len);
+            iov[i].iov_base,
-        if (ret < 0) {
+            iov[i].iov_len,
-            if (errno == EAGAIN) {
+            qatomic_load_acquire(&tioc->shutdown) & QIO_CHANNEL_SHUTDOWN_READ,
-                if (got) {
+            errp);
-                    return got;
+        if (ret == QCRYPTO_TLS_SESSION_ERR_BLOCK) {
-                } else {
+            if (got) {
-                    return QIO_CHANNEL_ERR_BLOCK;
+                return got;
-                }
+            } else {
-            } else if (errno == ECONNABORTED &&
+                return QIO_CHANNEL_ERR_BLOCK;
-                       (qatomic_load_acquire(&tioc->shutdown) &
-                        QIO_CHANNEL_SHUTDOWN_READ)) {
-                return 0;
             }
-
+        } else if (ret < 0) {
-            error_setg_errno(errp, errno,
-                             "Cannot read from TLS channel");
             return -1;
         }
         got += ret;
@@ -321,18 +314,15 @@ static ssize_t qio_channel_tls_writev(QIOChannel *ioc,
     for (i = 0 ; i < niov ; i++) {
         ssize_t ret = qcrypto_tls_session_write(tioc->session,
                                                 iov[i].iov_base,
-                                                iov[i].iov_len);
+                                                iov[i].iov_len,
-        if (ret <= 0) {
+                                                errp);
-            if (errno == EAGAIN) {
+        if (ret == QCRYPTO_TLS_SESSION_ERR_BLOCK) {
-                if (done) {
+            if (done) {
-                    return done;
+                return done;
-                } else {
+            } else {
-                    return QIO_CHANNEL_ERR_BLOCK;
+                return QIO_CHANNEL_ERR_BLOCK;
-                }
             }
-
+        } else if (ret < 0) {
-            error_setg_errno(errp, errno,
-                             "Cannot write to TLS channel");
             return -1;
         }
         done += ret;

meson.build

@@ -1696,7 +1696,6 @@ endif
 if not gnutls_crypto.found()
   if (not get_option('gcrypt').auto() or have_system) and not get_option('nettle').enabled()
     gcrypt = dependency('libgcrypt', version: '>=1.8',
-                        method: 'config-tool',
                         required: get_option('gcrypt'))
     # Debian has removed -lgpg-error from libgcrypt-config
     # as it "spreads unnecessary dependencies" which in
@@ -1979,6 +1978,7 @@ endif
 tasn1 = not_found
 if gnutls.found()
   tasn1 = dependency('libtasn1',
+                     required: false,
                      method: 'pkg-config')
 endif
 keyutils = not_found
@@ -3343,6 +3343,7 @@ if have_block
   trace_events_subdirs += [
     'authz',
     'block',
+    'chardev',
     'io',
     'nbd',
     'scsi',
@@ -3354,7 +3355,6 @@ if have_system
     'audio',
     'backends',
     'backends/tpm',
-    'chardev',
     'ebpf',
     'hw/9pfs',
     'hw/acpi',

qapi/crypto.json

@@ -226,8 +226,6 @@
 # @iter-time: number of milliseconds to spend in PBKDF passphrase
 #     processing.  Currently defaults to 2000.  (since 2.8)
 #
-# @detached-header: create a detached LUKS header.  (since 9.0)
-#
 # Since: 2.6
 ##
 { 'struct': 'QCryptoBlockCreateOptionsLUKS',
@@ -237,8 +235,7 @@
             '*ivgen-alg': 'QCryptoIVGenAlgorithm',
             '*ivgen-hash-alg': 'QCryptoHashAlgorithm',
             '*hash-alg': 'QCryptoHashAlgorithm',
-            '*iter-time': 'int',
+            '*iter-time': 'int' }}
-            '*detached-header': 'bool'}}
 
 ##
 # @QCryptoBlockOpenOptions:

tests/qtest/meson.build

@@ -322,8 +322,7 @@ if gnutls.found()
   migration_files += [files('../unit/crypto-tls-psk-helpers.c'), gnutls]
 
   if tasn1.found()
-    migration_files += [files('../unit/crypto-tls-x509-helpers.c',
+    migration_files += [files('../unit/crypto-tls-x509-helpers.c'), tasn1]
-                              '../unit/pkix_asn1_tab.c'), tasn1]
   endif
 endif
 

tests/unit/crypto-tls-psk-helpers.c

@@ -20,7 +20,6 @@
 
 #include "qemu/osdep.h"
 
-#include "crypto-tls-x509-helpers.h"
 #include "crypto-tls-psk-helpers.h"
 #include "qemu/sockets.h"
 

tests/unit/crypto-tls-x509-helpers.c

@@ -20,15 +20,19 @@
 
 #include "qemu/osdep.h"
 
+#include <libtasn1.h>
+
 #include "crypto-tls-x509-helpers.h"
 #include "crypto/init.h"
 #include "qemu/sockets.h"
 
+#include "pkix_asn1_tab.c.inc"
+
 /*
  * This stores some static data that is needed when
  * encoding extensions in the x509 certs
  */
-asn1_node pkix_asn1;
+static asn1_node pkix_asn1;
 
 /*
  * To avoid consuming random entropy to generate keys,

tests/unit/crypto-tls-x509-helpers.h

@@ -23,7 +23,6 @@
 
 #include <gnutls/gnutls.h>
 #include <gnutls/x509.h>
-#include <libtasn1.h>
 
 
 #define QCRYPTO_TLS_TEST_CLIENT_NAME "ACME QEMU Client"
@@ -171,6 +170,4 @@ void test_tls_cleanup(const char *keyfile);
     };                                                                  \
     test_tls_generate_cert(&varname, cavarname.crt)
 
-extern const asn1_static_node pkix_asn1_tab[];
-
 #endif

tests/unit/meson.build

@@ -99,11 +99,11 @@ if have_block
      tasn1.found() and \
      host_os != 'windows'
     tests += {
-      'test-crypto-tlscredsx509': ['crypto-tls-x509-helpers.c', 'pkix_asn1_tab.c',
+      'test-crypto-tlscredsx509': ['crypto-tls-x509-helpers.c',
                                    tasn1, crypto, gnutls],
-      'test-crypto-tlssession': ['crypto-tls-x509-helpers.c', 'pkix_asn1_tab.c', 'crypto-tls-psk-helpers.c',
+      'test-crypto-tlssession': ['crypto-tls-x509-helpers.c', 'crypto-tls-psk-helpers.c',
                                  tasn1, crypto, gnutls],
-      'test-io-channel-tls': ['io-channel-helpers.c', 'crypto-tls-x509-helpers.c', 'pkix_asn1_tab.c',
+      'test-io-channel-tls': ['io-channel-helpers.c', 'crypto-tls-x509-helpers.c',
                               tasn1, io, crypto, gnutls]}
   endif
   if pam.found()

tests/unit/pkix_asn1_tab.c.inc

@@ -3,10 +3,7 @@
  * and is under copyright of various GNUTLS contributors.
  */
 
-#include "qemu/osdep.h"
+static const asn1_static_node pkix_asn1_tab[] = {
-#include "crypto-tls-x509-helpers.h"
-
-const asn1_static_node pkix_asn1_tab[] = {
   {"PKIX1", 536875024, 0},
   {0, 1073741836, 0},
   {"id-ce", 1879048204, 0},

tests/unit/test-crypto-tlssession.c

@@ -35,18 +35,40 @@
 #define PSKFILE WORKDIR "keys.psk"
 #define KEYFILE WORKDIR "key-ctx.pem"
 
-static ssize_t testWrite(const char *buf, size_t len, void *opaque)
+static ssize_t
+testWrite(const char *buf, size_t len, void *opaque, Error **errp)
 {
     int *fd = opaque;
+    int ret;
 
-    return write(*fd, buf, len);
+    ret = write(*fd, buf, len);
+    if (ret < 0) {
+        if (errno == EAGAIN) {
+            return QCRYPTO_TLS_SESSION_ERR_BLOCK;
+        } else {
+            error_setg_errno(errp, errno, "unable to write");
+            return -1;
+        }
+    }
+    return ret;
 }
 
-static ssize_t testRead(char *buf, size_t len, void *opaque)
+static ssize_t
+testRead(char *buf, size_t len, void *opaque, Error **errp)
 {
     int *fd = opaque;
+    int ret;
 
-    return read(*fd, buf, len);
+    ret = read(*fd, buf, len);
+    if (ret < 0) {
+        if (errno == EAGAIN) {
+            return QCRYPTO_TLS_SESSION_ERR_BLOCK;
+        } else {
+            error_setg_errno(errp, errno, "unable to read");
+            return -1;
+        }
+    }
+    return ret;
 }
 
 static QCryptoTLSCreds *test_tls_creds_psk_create(