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2016-07-12Clean up header guards that don't match their file nameMarkus Armbruster
Header guard symbols should match their file name to make guard collisions less likely. Offenders found with scripts/clean-header-guards.pl -vn. Cleaned up with scripts/clean-header-guards.pl, followed by some renaming of new guard symbols picked by the script to better ones. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Richard Henderson <rth@twiddle.net>
2016-07-12Use #include "..." for our own headers, <...> for othersMarkus Armbruster
Tracked down with an ugly, brittle and probably buggy Perl script. Also move includes converted to <...> up so they get included before ours where that's obviously okay. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Tested-by: Eric Blake <eblake@redhat.com> Reviewed-by: Richard Henderson <rth@twiddle.net>
2016-07-04crypto: allow default TLS priority to be chosen at build timeDaniel P. Berrange
Modern gnutls can use a global config file to control the crypto priority settings for TLS connections. For example the priority string "@SYSTEM" instructs gnutls to find the priority setting named "SYSTEM" in the global config file. Latest gnutls GIT codebase gained the ability to reference multiple priority strings in the config file, with the first one that is found to existing winning. This means it is now possible to configure QEMU out of the box with a default priority of "@QEMU,SYSTEM", which says to look for the settings "QEMU" first, and if not found, use the "SYSTEM" settings. To make use of this facility, we introduce the ability to set the QEMU default priority at build time via a new configure argument. It is anticipated that distro vendors will set this when building QEMU to a suitable value for use with distro crypto policy setup. eg current Fedora would run ./configure --tls-priority=@SYSTEM while future Fedora would run ./configure --tls-priority=@QEMU,SYSTEM Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-07-04crypto: add support for TLS priority string overrideDaniel P. Berrange
The gnutls default priority is either "NORMAL" (most historical versions of gnutls) which is a built-in label in gnutls code, or "@SYSTEM" (latest gnutls on Fedora at least) which refers to an admin customizable entry in a gnutls config file. Regardless of which default is used by a distro, they are both global defaults applying to all applications using gnutls. If a single application on the system needs to use a weaker set of crypto priorities, this potentially forces the weakness onto all applications. Or conversely if a single application wants a strong default than all others, it can't do this via the global config file. This adds an extra parameter to the tls credential object which allows the mgmt app / user to explicitly provide a priority string to QEMU when configuring TLS. For example, to use the "NORMAL" priority, but disable SSL 3.0 one can now configure QEMU thus: $QEMU -object tls-creds-x509,id=tls0,dir=/home/berrange/qemutls,\ priority="NORMAL:-VERS-SSL3.0" \ ..other args... If creating tls-creds-anon, whatever priority the user specifies will always have "+ANON-DH" appended to it, since that's mandatory to make the anonymous credentials work. Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-07-04crypto: implement sha224, sha384, sha512 and ripemd160 hashesDaniel P. Berrange
Wire up the nettle and gcrypt hash backends so that they can support the sha224, sha384, sha512 and ripemd160 hash algorithms. Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-07-04crypto: switch hash code to use nettle/gcrypt directlyDaniel P. Berrange
Currently the internal hash code is using the gnutls hash APIs. GNUTLS in turn is wrapping either nettle or gcrypt. Not only were the GNUTLS hash APIs not added until GNUTLS 2.9.10, but they don't expose support for all the algorithms QEMU needs to use with LUKS. Address this by directly wrapping nettle/gcrypt in QEMU and avoiding GNUTLS's extra layer of indirection. This gives us support for hash functions on a much wider range of platforms and opens up ability to support more hash functions. It also avoids a GNUTLS bug which would not correctly handle hashing of large data blocks if int != size_t. Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-07-04crypto: fix handling of iv generator hash defaultsDaniel P. Berrange
When opening an existing LUKS volume, if the iv generator is essiv, then the iv hash algorithm is mandatory to provide. We must report an error if it is omitted in the cipher mode spec, not silently default to hash 0 (md5). If the iv generator is not essiv, then we explicitly ignore any iv hash algorithm, rather than report an error, for compatibility with dm-crypt. When creating a new LUKS volume, if the iv generator is essiv and no iv hsah algorithm is provided, we should default to using the sha256 hash. Reported-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-06-20trace: split out trace events for crypto/ directoryDaniel P. Berrange
Move all trace-events for files in the crypto/ directory to their own file. Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-id: 1466066426-16657-4-git-send-email-berrange@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-13crypto: assert that qcrypto_hash_digest_len is in rangePaolo Bonzini
Otherwise unintended results could happen. For example, Coverity reports a division by zero in qcrypto_afsplit_hash. While this cannot really happen, it shows that the contract of qcrypto_hash_digest_len can be improved. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-06-13TLS: provide slightly more information when TLS certificate loading failsAlex Bligh
Give slightly more information when certification loading fails. Rather than have no information, you now get gnutls's only slightly less unhelpful error messages. Signed-off-by: Alex Bligh <alex@alex.org.uk> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-06-07crypto: Use DIV_ROUND_UPLaurent Vivier
Replace (((n) + (d) - 1) /(d)) by DIV_ROUND_UP(n,d). This patch is the result of coccinelle script scripts/coccinelle/round.cocci CC: Daniel P. Berrange <berrange@redhat.com> Signed-off-by: Laurent Vivier <lvivier@redhat.com> Reviewed-by: Daniel P. Berrange <berrange@redhat.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-05-19qemu-common: stop including qemu/bswap.h from qemu-common.hPaolo Bonzini
Move it to the actual users. There are still a few includes of qemu/bswap.h in headers; removing them is left for future work. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-30crypto: do an explicit check for nettle pbkdf functionsDaniel P. Berrange
Support for the PBKDF functions in nettle was not introduced until version 2.6. Some distros QEMU targets have older versions and thus lack PBKDF support. Address this by doing a check in configure for the desired function and then skipping compilation of the nettle-pbkdf.o module Reported-by: Wen Congyang <wency@cn.fujitsu.com> Tested-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-24Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into stagingPeter Maydell
* Log filtering from Alex and Peter * Chardev fix from Marc-André * config.status tweak from David * Header file tweaks from Markus, myself and Veronia (Outreachy candidate) * get_ticks_per_sec() removal from Rutuja (Outreachy candidate) * Coverity fix from myself * PKE implementation from myself, based on rth's XSAVE support # gpg: Signature made Thu 24 Mar 2016 20:15:11 GMT using RSA key ID 78C7AE83 # gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" # gpg: aka "Paolo Bonzini <pbonzini@redhat.com>" * remotes/bonzini/tags/for-upstream: (28 commits) target-i386: implement PKE for TCG config.status: Pass extra parameters char: translate from QIOChannel error to errno exec: fix error handling in file_ram_alloc cputlb: modernise the debug support qemu-log: support simple pid substitution for logs target-arm: dfilter support for in_asm qemu-log: dfilter-ise exec, out_asm, op and opt_op qemu-log: new option -dfilter to limit output qemu-log: Improve the "exec" TB execution logging qemu-log: Avoid function call for disabled qemu_log_mask logging qemu-log: correct help text for -d cpu tcg: pass down TranslationBlock to tcg_code_gen util: move declarations out of qemu-common.h Replaced get_tick_per_sec() by NANOSECONDS_PER_SECOND hw: explicitly include qemu-common.h and cpu.h include/crypto: Include qapi-types.h or qemu/bswap.h instead of qemu-common.h isa: Move DMA_transfer_handler from qemu-common.h to hw/isa/isa.h Move ParallelIOArg from qemu-common.h to sysemu/char.h Move QEMU_ALIGN_*() from qemu-common.h to qemu/osdep.h ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Conflicts: scripts/clean-includes
2016-03-22include/crypto: Include qapi-types.h or qemu/bswap.h instead of qemu-common.hMarkus Armbruster
qemu-common.h should only be included by .c files. Its file comment explains why: "No header file should depend on qemu-common.h, as this would easily lead to circular header dependencies." Several include/crypto/ headers include qemu-common.h, but either need just qapi-types.h from it, or qemu/bswap.h, or nothing at all. Replace or drop the include accordingly. tests/test-crypto-secret.c now misses qemu/module.h, so include it there. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22include/qemu/osdep.h: Don't include qapi/error.hMarkus Armbruster
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the Error typedef. Since then, we've moved to include qemu/osdep.h everywhere. Its file comment explains: "To avoid getting into possible circular include dependencies, this file should not include any other QEMU headers, with the exceptions of config-host.h, compiler.h, os-posix.h and os-win32.h, all of which are doing a similar job to this file and are under similar constraints." qapi/error.h doesn't do a similar job, and it doesn't adhere to similar constraints: it includes qapi-types.h. That's in excess of 100KiB of crap most .c files don't actually need. Add the typedef to qemu/typedefs.h, and include that instead of qapi/error.h. Include qapi/error.h in .c files that need it and don't get it now. Include qapi-types.h in qom/object.h for uint16List. Update scripts/clean-includes accordingly. Update it further to match reality: replace config.h by config-target.h, add sysemu/os-posix.h, sysemu/os-win32.h. Update the list of includes in the qemu/osdep.h comment quoted above similarly. This reduces the number of objects depending on qapi/error.h from "all of them" to less than a third. Unfortunately, the number depending on qapi-types.h shrinks only a little. More work is needed for that one. Signed-off-by: Markus Armbruster <armbru@redhat.com> [Fix compilation without the spice devel packages. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-21crypto: fix cipher function signature mismatch with nettle & xtsDaniel P. Berrange
For versions of nettle < 3.0.0, the cipher functions took a 'void *ctx' and 'unsigned len' instad of 'const void *ctx' and 'size_t len'. The xts functions though are builtin to QEMU and always expect the latter signatures. Define a second set of wrappers to use with the correct signatures needed by XTS mode. Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-21crypto: add compat cast5_set_key with nettle < 3.0.0Daniel P. Berrange
Prior to the nettle 3.0.0 release, the cast5_set_key function was actually named cast128_set_key, so we must add a compatibility definition. Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17crypto: implement the LUKS block encryption formatDaniel P. Berrange
Provide a block encryption implementation that follows the LUKS/dm-crypt specification. This supports all combinations of hash, cipher algorithm, cipher mode and iv generator that are implemented by the current crypto layer. There is support for opening existing volumes formatted by dm-crypt, and for formatting new volumes. In the latter case it will only use key slot 0. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17crypto: add block encryption frameworkDaniel P. Berrange
Add a generic framework for supporting different block encryption formats. Upon instantiating a QCryptoBlock object, it will read the encryption header and extract the encryption keys. It is then possible to call methods to encrypt/decrypt data buffers. There is also a mode whereby it will create/initialize a new encryption header on a previously unformatted volume. The initial framework comes with support for the legacy QCow AES based encryption. This enables code in the QCow driver to be consolidated later. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17crypto: wire up XTS mode for cipher APIsDaniel P. Berrange
Introduce 'XTS' as a permitted mode for the cipher APIs. With XTS the key provided must be twice the size of the key normally required for any given algorithm. This is because the key will be split into two pieces for use in XTS mode. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17crypto: refactor code for dealing with AES cipherDaniel P. Berrange
The built-in and nettle cipher backends for AES maintain two separate AES contexts, one for encryption and one for decryption. This is going to be inconvenient for the future code dealing with XTS, so wrap them up in a single struct so there is just one pointer to pass around for both encryption and decryption. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17crypto: import an implementation of the XTS cipher modeDaniel P. Berrange
The XTS (XEX with tweaked-codebook and ciphertext stealing) cipher mode is commonly used in full disk encryption. There is unfortunately no implementation of it in either libgcrypt or nettle, so we need to provide our own. The libtomcrypt project provides a repository of crypto algorithms under a choice of either "public domain" or the "what the fuck public license". So this impl is taken from the libtomcrypt GIT repo and adapted to be compatible with the way we need to call ciphers provided by nettle/gcrypt. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17crypto: add support for the twofish cipher algorithmDaniel P. Berrange
New cipher algorithms 'twofish-128', 'twofish-192' and 'twofish-256' are defined for the Twofish algorithm. The gcrypt backend does not support 'twofish-192'. The nettle and gcrypt cipher backends are updated to support the new cipher and a test vector added to the cipher test suite. The new algorithm is enabled in the LUKS block encryption driver. Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17crypto: add support for the serpent cipher algorithmDaniel P. Berrange
New cipher algorithms 'serpent-128', 'serpent-192' and 'serpent-256' are defined for the Serpent algorithm. The nettle and gcrypt cipher backends are updated to support the new cipher and a test vector added to the cipher test suite. The new algorithm is enabled in the LUKS block encryption driver. Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17crypto: add support for the cast5-128 cipher algorithmDaniel P. Berrange
A new cipher algorithm 'cast-5-128' is defined for the Cast-5 algorithm with 128 bit key size. Smaller key sizes are supported by Cast-5, but nothing in QEMU should use them, so only 128 bit keys are permitted. The nettle and gcrypt cipher backends are updated to support the new cipher and a test vector added to the cipher test suite. The new algorithm is enabled in the LUKS block encryption driver. Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17crypto: add support for anti-forensic split algorithmDaniel P. Berrange
The LUKS format specifies an anti-forensic split algorithm which is used to artificially expand the size of the key material on disk. This is an implementation of that algorithm. Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17crypto: add support for generating initialization vectorsDaniel P. Berrange
There are a number of different algorithms that can be used to generate initialization vectors for disk encryption. This introduces a simple internal QCryptoBlockIV object to provide a consistent internal API to the different algorithms. The initially implemented algorithms are 'plain', 'plain64' and 'essiv', each matching the same named algorithm provided by the Linux kernel dm-crypt driver. Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17crypto: add support for PBKDF2 algorithmDaniel P. Berrange
The LUKS data format includes use of PBKDF2 (Password-Based Key Derivation Function). The Nettle library can provide an implementation of this, but we don't want code directly depending on a specific crypto library backend. Introduce a new include/crypto/pbkdf.h header which defines a QEMU API for invoking PBKDK2. The initial implementations are backed by nettle & gcrypt, which are commonly available with distros shipping GNUTLS. The test suite data is taken from the cryptsetup codebase under the LGPLv2.1+ license. This merely aims to verify that whatever backend we provide for this function in QEMU will comply with the spec. Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17crypto: add cryptographic random byte sourceDaniel P. Berrange
There are three backend impls provided. The preferred is gnutls, which is backed by nettle in modern distros. The gcrypt impl is provided for cases where QEMU build against gnutls is disabled, but crypto is still desired. No nettle impl is provided, since it is non-trivial to use the nettle APIs for random numbers. Users of nettle should ensure gnutls is enabled for QEMU. Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-02-02crypto: ensure qcrypto_hash_digest_len is always definedDaniel P. Berrange
The qcrypto_hash_digest_len method was accidentally inside a CONFIG_GNUTLS_HASH block, even though it doesn't depend on gnutls. Re-arrange it to be unconditionally defined. Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-02-01crypto: register properties against the class instead of objectDaniel P. Berrange
This converts the tlscredsx509, tlscredsanon and secret objects to register their properties against the class rather than object. Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-01-29crypto: Clean up includesPeter Maydell
Clean up includes so that osdep.h is included first and headers which it implies are not included manually. This commit was created with scripts/clean-includes. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Message-id: 1453832250-766-3-git-send-email-peter.maydell@linaro.org
2016-01-22fpu: Replace uint8 typedef with uint8_tPeter Maydell
Replace the uint8 softfloat-specific typedef with uint8_t. This change was made with find include hw fpu target-* -name '*.[ch]' | xargs sed -i -e 's/\buint8\b/uint8_t/g' together with manual removal of the typedef definition and manual fixing of more erroneous uses found via test compilation. It turns out that the only code using this type is an accidental use where uint8_t was intended anyway... Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net> Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Acked-by: Leon Alrae <leon.alrae@imgtec.com> Acked-by: James Hogan <james.hogan@imgtec.com> Message-id: 1452603315-27030-7-git-send-email-peter.maydell@linaro.org
2015-12-23crypto: fix transposed arguments in cipher error messageDaniel P. Berrange
When reporting an incorrect key length for a cipher, we mixed up the actual vs expected arguments. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-12-23crypto: move QCryptoCipherAlgorithm/Mode enum definitions into QAPIDaniel P. Berrange
The QCryptoCipherAlgorithm and QCryptoCipherMode enums are defined in the crypto/cipher.h header. In the future some QAPI types will want to reference the hash enums, so move the enum definition into QAPI too. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-12-23crypto: move QCryptoHashAlgorithm enum definition into QAPIDaniel P. Berrange
The QCryptoHashAlgorithm enum is defined in the crypto/hash.h header. In the future some QAPI types will want to reference the hash enums, so move the enum definition into QAPI too. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-12-23crypto: add ability to query hash digest lenDaniel P. Berrange
Add a qcrypto_hash_digest_len() method which allows querying of the raw digest size for a given hash algorithm. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-12-23crypto: add additional query accessors for cipher instancesDaniel P. Berrange
Adds new methods to allow querying the length of the cipher key, block size and initialization vectors. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-12-18crypto: add support for loading encrypted x509 keysDaniel P. Berrange
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 # $QEMU \ -object secret,id=sec0,filename=mypasswd.txt \ -object tls-creds-x509,passwordid=sec0,id=creds0,\ dir=/home/berrange/.pki/qemu,endpoint=server \ -vnc :1,tls-creds=creds0 This requires QEMU to be linked to GNUTLS >= 3.1.11. If GNUTLS is too old an error will be reported if an attempt is made to pass a decryption password. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-12-18crypto: add QCryptoSecret object class for password/key handlingDaniel P. Berrange
Introduce a new QCryptoSecret object class which will be used for providing passwords and keys to other objects which need sensitive credentials. The new object can provide secret values directly as properties, or indirectly via a file. The latter includes support for file descriptor passing syntax on UNIX platforms. Ordinarily passing secret values directly as properties is insecure, since they are visible in process listings, or in log files showing the CLI args / QMP commands. It is possible to use AES-256-CBC to encrypt the secret values though, in which case all that is visible is the ciphertext. For ad hoc developer testing though, it is fine to provide the secrets directly without encryption so this is not explicitly forbidden. The anticipated scenario is that libvirtd will create a random master key per QEMU instance (eg /var/run/libvirt/qemu/$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: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-12-04crypto: avoid two coverity false positive error reportsDaniel P. Berrange
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: Daniel P. Berrange <berrange@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-11-18crypto: avoid passing NULL to access() syscallDaniel P. Berrange
The qcrypto_tls_creds_x509_sanity_check() checks whether certs exist by calling access(). It is valid for this method to be invoked with certfile==NULL though, since for client credentials the cert is optional. This caused it to call access(NULL), which happens to be harmless on current Linux, but should none the less be avoided. Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-11-18crypto: fix mistaken setting of Error in success code pathDaniel P. Berrange
The qcrypto_tls_session_check_certificate() method was setting an Error even when the ACL check suceeded. This didn't affect the callers detection of errors because they relied on the function return status, but this did cause a memory leak since the caller would not free an Error they did not expect to be set. Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-11-18crypto: fix leak of gnutls_dh_params_t data on credential unloadDaniel P. Berrange
The QCryptoTLSCredsX509 object was not free'ing the allocated gnutls_dh_params_t data when unloading the credentials Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-10-22crypto: add sanity checking of plaintext/ciphertext lengthDaniel P. Berrange
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: Daniel P. Berrange <berrange@redhat.com>
2015-10-22crypto: don't let builtin aes crash if no IV is providedDaniel P. Berrange
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: Daniel P. Berrange <berrange@redhat.com>
2015-10-22crypto: allow use of nettle/gcrypt to be selected explicitlyDaniel P. Berrange
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: Daniel P. Berrange <berrange@redhat.com>
2015-09-15crypto: introduce new module for handling TLS sessionsDaniel P. Berrange
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: Daniel P. Berrange <berrange@redhat.com>
2015-09-15crypto: add sanity checking of TLS x509 credentialsDaniel P. Berrange
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: Daniel P. Berrange <berrange@redhat.com>