From 1d7b5b4afdcd76e24ec3678d5418b29d4ff06ad9 Mon Sep 17 00:00:00 2001 From: "Daniel P. Berrange" Date: Thu, 15 Oct 2015 16:14:42 +0100 Subject: [PATCH] crypto: add support for loading encrypted x509 keys 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 Signed-off-by: Daniel P. Berrange --- crypto/tlscredsx509.c | 48 +++++++++++++++++++++++++++++++++++++++++++ include/crypto/tlscredsx509.h | 1 + qemu-options.hx | 8 +++++++- 3 files changed, 56 insertions(+), 1 deletion(-) diff --git a/crypto/tlscredsx509.c b/crypto/tlscredsx509.c index 26f18cb..d58fdea 100644 --- a/crypto/tlscredsx509.c +++ b/crypto/tlscredsx509.c @@ -20,6 +20,7 @@ #include "crypto/tlscredsx509.h" #include "crypto/tlscredspriv.h" +#include "crypto/secret.h" #include "qom/object_interfaces.h" #include "trace.h" @@ -607,9 +608,30 @@ qcrypto_tls_creds_x509_load(QCryptoTLSCredsX509 *creds, } if (cert != NULL && key != NULL) { +#if GNUTLS_VERSION_NUMBER >= 0x030111 + char *password = NULL; + if (creds->passwordid) { + password = qcrypto_secret_lookup_as_utf8(creds->passwordid, + errp); + if (!password) { + goto cleanup; + } + } + ret = gnutls_certificate_set_x509_key_file2(creds->data, + cert, key, + GNUTLS_X509_FMT_PEM, + password, + 0); + g_free(password); +#else /* GNUTLS_VERSION_NUMBER < 0x030111 */ + if (creds->passwordid) { + error_setg(errp, "PKCS8 decryption requires GNUTLS >= 3.1.11"); + goto cleanup; + } ret = gnutls_certificate_set_x509_key_file(creds->data, cert, key, GNUTLS_X509_FMT_PEM); +#endif /* GNUTLS_VERSION_NUMBER < 0x030111 */ if (ret < 0) { error_setg(errp, "Cannot load certificate '%s' & key '%s': %s", cert, key, gnutls_strerror(ret)); @@ -737,6 +759,27 @@ qcrypto_tls_creds_x509_prop_set_sanity(Object *obj, } +static void +qcrypto_tls_creds_x509_prop_set_passwordid(Object *obj, + const char *value, + Error **errp G_GNUC_UNUSED) +{ + QCryptoTLSCredsX509 *creds = QCRYPTO_TLS_CREDS_X509(obj); + + creds->passwordid = g_strdup(value); +} + + +static char * +qcrypto_tls_creds_x509_prop_get_passwordid(Object *obj, + Error **errp G_GNUC_UNUSED) +{ + QCryptoTLSCredsX509 *creds = QCRYPTO_TLS_CREDS_X509(obj); + + return g_strdup(creds->passwordid); +} + + static bool qcrypto_tls_creds_x509_prop_get_sanity(Object *obj, Error **errp G_GNUC_UNUSED) @@ -769,6 +812,10 @@ qcrypto_tls_creds_x509_init(Object *obj) qcrypto_tls_creds_x509_prop_get_sanity, qcrypto_tls_creds_x509_prop_set_sanity, NULL); + object_property_add_str(obj, "passwordid", + qcrypto_tls_creds_x509_prop_get_passwordid, + qcrypto_tls_creds_x509_prop_set_passwordid, + NULL); } @@ -777,6 +824,7 @@ qcrypto_tls_creds_x509_finalize(Object *obj) { QCryptoTLSCredsX509 *creds = QCRYPTO_TLS_CREDS_X509(obj); + g_free(creds->passwordid); qcrypto_tls_creds_x509_unload(creds); } diff --git a/include/crypto/tlscredsx509.h b/include/crypto/tlscredsx509.h index b9785fd..25796d7 100644 --- a/include/crypto/tlscredsx509.h +++ b/include/crypto/tlscredsx509.h @@ -101,6 +101,7 @@ struct QCryptoTLSCredsX509 { gnutls_certificate_credentials_t data; #endif bool sanityCheck; + char *passwordid; }; diff --git a/qemu-options.hx b/qemu-options.hx index f37a2eb..49afe6c 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -3627,7 +3627,7 @@ expensive operation that consumes random pool entropy, so it is recommended that a persistent set of parameters be generated upfront and saved. -@item -object tls-creds-x509,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off} +@item -object tls-creds-x509,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off},passwordid=@var{id} Creates a TLS anonymous credentials object, which can be used to provide TLS support on network backends. The @option{id} parameter is a unique @@ -3654,6 +3654,12 @@ in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional), @var{server-cert.pem} (only servers), @var{server-key.pem} (only servers), @var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients). +For the @var{server-key.pem} and @var{client-key.pem} files which +contain sensitive private keys, it is possible to use an encrypted +version by providing the @var{passwordid} parameter. This provides +the ID of a previously created @code{secret} object containing the +password for decryption. + @item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}] Interval @var{t} can't be 0, this filter batches the packet delivery: all -- 2.7.4