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  1. 17 3月, 2016 11 次提交
  3. 02 2月, 2016 1 次提交
  5. 01 2月, 2016 1 次提交
  7. 29 1月, 2016 1 次提交
  9. 22 1月, 2016 1 次提交
  11. 23 12月, 2015 5 次提交
  13. 19 12月, 2015 2 次提交
    • D
      crypto: add support for loading encrypted x509 keys · 1d7b5b4a
      由 Daniel P. Berrange 提交于 
      Make use of the QCryptoSecret object to support loading of
encrypted x509 keys. The optional 'passwordid' parameter
to the tls-creds-x509 object type, provides the ID of a
secret object instance that holds the decryption password
for the PEM file.

 # printf "123456" > mypasswd.txt
 # $QEMU \
    -object secret,id=sec0,filename=mypasswd.txt \
    -object tls-creds-x509,passwordid=sec0,id=creds0,\
            dir=/home/berrange/.pki/qemu,endpoint=server \
    -vnc :1,tls-creds=creds0

This requires QEMU to be linked to GNUTLS >= 3.1.11. If
GNUTLS is too old an error will be reported if an attempt
is made to pass a decryption password.
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
      1d7b5b4a
    • D
      crypto: add QCryptoSecret object class for password/key handling · ac1d8878
      由 Daniel P. Berrange 提交于 
      Introduce a new QCryptoSecret object class which will be used
for providing passwords and keys to other objects which need
sensitive credentials.

The new object can provide secret values directly as properties,
or indirectly via a file. The latter includes support for file
descriptor passing syntax on UNIX platforms. Ordinarily passing
secret values directly as properties is insecure, since they
are visible in process listings, or in log files showing the
CLI args / QMP commands. It is possible to use AES-256-CBC to
encrypt the secret values though, in which case all that is
visible is the ciphertext.  For ad hoc developer testing though,
it is fine to provide the secrets directly without encryption
so this is not explicitly forbidden.

The anticipated scenario is that libvirtd will create a random
master key per QEMU instance (eg /var/run/libvirt/qemu/$VMNAME.key)
and will use that key to encrypt all passwords it provides to
QEMU via '-object secret,....'.  This avoids the need for libvirt
(or other mgmt apps) to worry about file descriptor passing.

It also makes life easier for people who are scripting the
management of QEMU, for whom FD passing is significantly more
complex.

Providing data inline (insecure, only for ad hoc dev testing)

  $QEMU -object secret,id=sec0,data=letmein

Providing data indirectly in raw format

  printf "letmein" > mypasswd.txt
  $QEMU -object secret,id=sec0,file=mypasswd.txt

Providing data indirectly in base64 format

  $QEMU -object secret,id=sec0,file=mykey.b64,format=base64

Providing data with encryption

  $QEMU -object secret,id=master0,file=mykey.b64,format=base64 \
        -object secret,id=sec0,data=[base64 ciphertext],\
	           keyid=master0,iv=[base64 IV],format=base64

Note that 'format' here refers to the format of the ciphertext
data. The decrypted data must always be in raw byte format.

More examples are shown in the updated docs.
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
      ac1d8878
  15. 04 12月, 2015 1 次提交
    • D
      crypto: avoid two coverity false positive error reports · 0e1d0245
      由 Daniel P. Berrange 提交于 
      In qcrypto_tls_creds_get_path() coverity complains that
we are checking '*creds' for NULL, despite having
dereferenced it previously. This is harmless bug due
to fact that the trace call was too early. Moving it
after the cleanup gets the desired semantics.

In qcrypto_tls_creds_check_cert_key_purpose() coverity
complains that we're passing a pointer to a previously
free'd buffer into gnutls_x509_crt_get_key_purpose_oid()
This is harmless because we're passing a size == 0, so
gnutls won't access the buffer, but rather just report
what size it needs to be. We can avoid it though by
explicitly setting the buffer to NULL after free'ing
it.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>
      0e1d0245
  17. 18 11月, 2015 3 次提交
  19. 23 10月, 2015 3 次提交
    • D
      crypto: add sanity checking of plaintext/ciphertext length · 3a661f1e
      由 Daniel P. Berrange 提交于 
      When encrypting/decrypting data, the plaintext/ciphertext
buffers are required to be a multiple of the cipher block
size. If this is not done, nettle will abort and gcrypt
will report an error. To get consistent behaviour add
explicit checks upfront for the buffer sizes.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
      3a661f1e
    • D
      crypto: don't let builtin aes crash if no IV is provided · eb2a770b
      由 Daniel P. Berrange 提交于 
      If no IV is provided, then use a default IV of all-zeros
instead of crashing. This gives parity with gcrypt and
nettle backends.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
      eb2a770b
    • D
      crypto: allow use of nettle/gcrypt to be selected explicitly · 91bfcdb0
      由 Daniel P. Berrange 提交于 
      Currently the choice of whether to use nettle or gcrypt is
made based on what gnutls is linked to. There are times
when it is desirable to be able to force build against a
specific library. For example, if testing changes to QEMU's
crypto code all 3 possible backends need to be checked
regardless of what the local gnutls uses.

It is also desirable to be able to enable nettle/gcrypt
for cipher/hash algorithms, without enabling gnutls
for TLS support.

This gives two new configure flags, which allow the
following possibilities

Automatically determine nettle vs gcrypt from what
gnutls links to (recommended to minimize number of
crypto libraries linked to)

 ./configure

Automatically determine nettle vs gcrypt based on
which is installed

 ./configure --disable-gnutls

Force use of nettle

 ./configure --enable-nettle

Force use of gcrypt

 ./configure --enable-gcrypt

Force use of built-in AES & crippled-DES

 ./configure --disable-nettle --disable-gcrypt
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
      91bfcdb0
  21. 15 9月, 2015 6 次提交
    • D
      crypto: introduce new module for handling TLS sessions · d321e1e5
      由 Daniel P. Berrange 提交于 
      Introduce a QCryptoTLSSession object that will encapsulate
all the code for setting up and using a client/sever TLS
session. This isolates the code which depends on the gnutls
library, avoiding #ifdefs in the rest of the codebase, as
well as facilitating any possible future port to other TLS
libraries, if desired. It makes use of the previously
defined QCryptoTLSCreds object to access credentials to
use with the session. It also includes further unit tests
to validate the correctness of the TLS session handshake
and certificate validation. This is functionally equivalent
to the current TLS session handling code embedded in the
VNC server, and will obsolete it.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
      d321e1e5
    • D
      crypto: add sanity checking of TLS x509 credentials · 9a2fd434
      由 Daniel P. Berrange 提交于 
      If the administrator incorrectly sets up their x509 certificates,
the errors seen at runtime during connection attempts are very
obscure and difficult to diagnose. This has been a particular
problem for people using openssl to generate their certificates
instead of the gnutls certtool, because the openssl tools don't
turn on the various x509 extensions that gnutls expects to be
present by default.

This change thus adds support in the TLS credentials object to
sanity check the certificates when QEMU first loads them. This
gives the administrator immediate feedback for the majority of
common configuration mistakes, reducing the pain involved in
setting up TLS. The code is derived from equivalent code that
has been part of libvirt's TLS support and has been seen to be
valuable in assisting admins.

It is possible to disable the sanity checking, however, via
the new 'sanity-check' property on the tls-creds object type,
with a value of 'no'.

Unit tests are included in this change to verify the correctness
of the sanity checking code in all the key scenarios it is
intended to cope with. As part of the test suite, the pkix_asn1_tab.c
from gnutls is imported. This file is intentionally copied from the
(long since obsolete) gnutls 1.6.3 source tree, since that version
was still under GPLv2+, rather than the GPLv3+ of gnutls >= 2.0.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
      9a2fd434
    • D
      crypto: introduce new module for TLS x509 credentials · 85bcbc78
      由 Daniel P. Berrange 提交于 
      Introduce a QCryptoTLSCredsX509 class which is used to
manage x509 certificate TLS credentials. This will be
the preferred credential type offering strong security
characteristics

Example CLI configuration:

 $QEMU -object tls-creds-x509,id=tls0,endpoint=server,\
               dir=/path/to/creds/dir,verify-peer=yes

The 'id' value in the -object args will be used to associate the
credentials with the network services. For example, when the VNC
server is later converted it would use

 $QEMU -object tls-creds-x509,id=tls0,.... \
       -vnc 127.0.0.1:1,tls-creds=tls0
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
      85bcbc78
    • D
      crypto: introduce new module for TLS anonymous credentials · e00adf6c
      由 Daniel P. Berrange 提交于 
      Introduce a QCryptoTLSCredsAnon class which is used to
manage anonymous TLS credentials. Use of this class is
generally discouraged since it does not offer strong
security, but it is required for backwards compatibility
with the current VNC server implementation.

Simple example CLI configuration:

 $QEMU -object tls-creds-anon,id=tls0,endpoint=server

Example using pre-created diffie-hellman parameters

 $QEMU -object tls-creds-anon,id=tls0,endpoint=server,\
               dir=/path/to/creds/dir

The 'id' value in the -object args will be used to associate the
credentials with the network services. For example, when the VNC
server is later converted it would use

 $QEMU -object tls-creds-anon,id=tls0,.... \
       -vnc 127.0.0.1:1,tls-creds=tls0
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
      e00adf6c
    • D
      crypto: introduce new base module for TLS credentials · a090187d
      由 Daniel P. Berrange 提交于 
      Introduce a QCryptoTLSCreds class to act as the base class for
storing TLS credentials. This will be later subclassed to provide
handling of anonymous and x509 credential types. The subclasses
will be user creatable objects, so instances can be created &
deleted via 'object-add' and 'object-del' QMP commands respectively,
or via the -object command line arg.

If the credentials cannot be initialized an error will be reported
as a QMP reply, or on stderr respectively.

The idea is to make it possible to represent and manage TLS
credentials independently of the network service that is using
them. This will enable multiple services to use the same set of
credentials and minimize code duplication. A later patch will
convert the current VNC server TLS code over to use this object.

The representation of credentials will be functionally equivalent
to that currently implemented in the VNC server with one exception.
The new code has the ability to (optionally) load a pre-generated
set of diffie-hellman parameters, if the file dh-params.pem exists,
whereas the current VNC server will always generate them on startup.
This is beneficial for admins who wish to avoid the (small) time
sink of generating DH parameters at startup and/or avoid depleting
entropy.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
      a090187d
    • D
      crypto: move crypto objects out of libqemuutil.la · fb37726d
      由 Daniel P. Berrange 提交于 
      Future patches will be adding more crypto related APIs which
rely on QOM infrastructure. This creates a problem, because
QOM relies on library constructors to register objects. When
you have a file in a static .a library though which is only
referenced by a constructor the linker is dumb and will drop
that file when linking to the final executable :-( The only
workaround for this is to link the .a library to the executable
using the -Wl,--whole-archive flag, but this creates its own
set of problems because QEMU is relying on lazy linking for
libqemuutil.a. Using --whole-archive majorly increases the
size of final executables as they now contain a bunch of
object code they don't actually use.

The least bad option is to thus not include the crypto objects
in libqemuutil.la, and instead define a crypto-obj-y variable
that is referenced directly by all the executables that need
this code (tools + softmmu, but not qemu-ga). We avoid pulling
entire of crypto-obj-y into the userspace emulators as that
would force them to link to gnutls too, which is not required.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
      fb37726d
  23. 27 7月, 2015 1 次提交
  25. 20 7月, 2015 1 次提交
  27. 17 7月, 2015 2 次提交
    • R
      crypto: avoid undefined behavior in nettle calls · d3462e37
      由 Radim Krčmář 提交于 
      Calling a function pointer that was cast from an incompatible function
results in undefined behavior.  'void *' isn't compatible with 'struct
XXX *', so we can't cast to nettle_cipher_func, but have to provide a
wrapper.  (Conversion from 'void *' to 'struct XXX *' might require
computation, which won't be done if we drop argument's true type, and
pointers can have different sizes so passing arguments on stack would
bug.)

Having two different prototypes based on nettle version doesn't make
this solution any nicer.
Reported-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
Message-Id: <1437062641-12684-3-git-send-email-rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      d3462e37
    • R
      crypto: fix build with nettle >= 3.0.0 · becaeb72
      由 Radim Krčmář 提交于 
      In nettle 3, cbc_encrypt() accepts 'nettle_cipher_func' instead of
'nettle_crypt_func' and these two differ in 'const' qualifier of the
first argument.  The build fails with:

  In file included from crypto/cipher.c:71:0:
  ./crypto/cipher-nettle.c: In function ‘qcrypto_cipher_encrypt’:
  ./crypto/cipher-nettle.c:154:38: error: passing argument 2 of
  ‘nettle_cbc_encrypt’ from incompatible pointer type
           cbc_encrypt(ctx->ctx_encrypt, ctx->alg_encrypt,
                                               ^
  In file included from ./crypto/cipher-nettle.c:24:0,
                   from crypto/cipher.c:71:
  /usr/include/nettle/cbc.h:48:1: note: expected
  ‘void (*)(const void *, size_t, uint8_t *, const uint8_t *)
  but argument is of type
  ‘void (*)(      void *, size_t, uint8_t *, const uint8_t *)

To allow both versions, we switch to the new definition and #if typedef
it for old versions.
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
Message-Id: <1436548682-9315-2-git-send-email-rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      becaeb72
  29. 09 7月, 2015 1 次提交