8:12 a.m.
From: "Daniel P. Berrange" <berrange(a)redhat.com>
If key usage or purpose data is not present in the cert, the
RFC recommends that access be allowed. Also fix checking of
key usage to include requirements for client/server certs,
and fix key purpose checking to treat data as a list of bits
---
src/rpc/virnettlscontext.c | 78 +++++++++++++++++++++++++------------------
1 files changed, 45 insertions(+), 33 deletions(-)
diff --git a/src/rpc/virnettlscontext.c b/src/rpc/virnettlscontext.c
index 402029f..1ee5ab2 100644
--- a/src/rpc/virnettlscontext.c
+++ b/src/rpc/virnettlscontext.c
@@ -111,6 +111,7 @@ static gnutls_x509_crt_t virNetTLSContextSanityCheckCert(bool
isServer,
char *buffer = NULL;
size_t size;
unsigned int usage;
+ bool allowClient = false, allowServer = false;
VIR_DEBUG("isServer %d isCA %d certFile %s",
isServer, isCA, certFile);
@@ -193,24 +194,34 @@ static gnutls_x509_crt_t virNetTLSContextSanityCheckCert(bool
isServer,
VIR_DEBUG("Cert %s key usage status %d usage %d", certFile, status,
usage);
if (status < 0) {
- virNetError(VIR_ERR_SYSTEM_ERROR,
- _("Unable to query certificate %s key usage %s"),
- certFile, gnutls_strerror(status));
- goto cleanup;
+ if (status == GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE) {
+ usage = isCA ? GNUTLS_KEY_KEY_CERT_SIGN :
+ GNUTLS_KEY_DIGITAL_SIGNATURE|GNUTLS_KEY_KEY_ENCIPHERMENT;
+ } else {
+ virNetError(VIR_ERR_SYSTEM_ERROR,
+ _("Unable to query certificate %s key usage %s"),
+ certFile, gnutls_strerror(status));
+ goto cleanup;
+ }
}
- if (usage & GNUTLS_KEY_KEY_CERT_SIGN) {
- if (!isCA) {
- virNetError(VIR_ERR_SYSTEM_ERROR, isServer ?
- _("Certificate %s usage is for certificate signing, but
wanted a server certificate") :
- _("Certificate %s usage is for certificate signing, but
wanted a client certificate"),
+ if (isCA) {
+ if (!(usage & GNUTLS_KEY_KEY_CERT_SIGN)) {
+ virNetError(VIR_ERR_SYSTEM_ERROR,
+ _("Certificate %s usage does not permit certificate
signing"),
certFile);
goto cleanup;
}
} else {
- if (isCA) {
+ if (!(usage & GNUTLS_KEY_DIGITAL_SIGNATURE)) {
+ virNetError(VIR_ERR_SYSTEM_ERROR,
+ _("Certificate %s usage does not permit digital
signature"),
+ certFile);
+ goto cleanup;
+ }
+ if (!(usage & GNUTLS_KEY_KEY_ENCIPHERMENT)) {
virNetError(VIR_ERR_SYSTEM_ERROR,
- _("Certificate %s usage is for not certificate
signing"),
+ _("Certificate %s usage does not permit key
encipherment"),
certFile);
goto cleanup;
}
@@ -221,7 +232,11 @@ static gnutls_x509_crt_t virNetTLSContextSanityCheckCert(bool
isServer,
status = gnutls_x509_crt_get_key_purpose_oid(cert, i, buffer, &size, NULL);
if (status == GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE) {
- VIR_DEBUG("No key purpose data available, skipping checks");
+ VIR_DEBUG("No key purpose data available at slot %d", i);
+
+ /* If there is no data at all, then we must allow client/server to pass */
+ if (i == 0)
+ allowServer = allowClient = true;
break;
}
if (status != GNUTLS_E_SHORT_MEMORY_BUFFER) {
@@ -246,34 +261,31 @@ static gnutls_x509_crt_t virNetTLSContextSanityCheckCert(bool
isServer,
VIR_DEBUG("Key purpose %d %s", status, buffer);
if (STREQ(buffer, GNUTLS_KP_TLS_WWW_SERVER)) {
- if (isCA || !isServer) {
- virNetError(VIR_ERR_SYSTEM_ERROR, isCA ?
- _("Certificate %s purpose is TLS server, but wanted a CA
certificate") :
- _("Certificate %s client purpose is TLS server, but
wanted a TLS client certificate"),
- certFile);
- goto cleanup;
- }
+ allowServer = true;
} else if (STREQ(buffer, GNUTLS_KP_TLS_WWW_CLIENT)) {
- if (isCA || isServer) {
- virNetError(VIR_ERR_SYSTEM_ERROR, isCA ?
- _("Certificate %s purpose is TLS client, but wanted a CA
certificate") :
- _("Certificate %s server purpose is TLS client, but
wanted a TLS server certificate"),
- certFile);
- goto cleanup;
- }
+ allowClient = true;
} else if (STRNEQ(buffer, GNUTLS_KP_ANY)) {
- virNetError(VIR_ERR_SYSTEM_ERROR, (isCA ?
- _("Certificate %s purpose is wrong, wanted a CA
certificate") :
- (isServer ?
- _("Certificate %s purpose is wrong, wanted a TLS server
certificate") :
- _("Certificate %s purpose is wrong, wanted a TLS client
certificate"))),
- certFile);
- goto cleanup;
+ allowServer = allowClient = true;
}
VIR_FREE(buffer);
}
+ if (!isCA) { /* No purpose checks required for CA certs */
+ if (isServer && !allowServer) {
+ virNetError(VIR_ERR_SYSTEM_ERROR,
+ _("Certificate %s purpose does not allow use for with a TLS
server"),
+ certFile);
+ goto cleanup;
+ }
+ if (!isServer && !allowClient) {
+ virNetError(VIR_ERR_SYSTEM_ERROR,
+ _("Certificate %s purpose does not allow use for with a TLS
client"),
+ certFile);
+ goto cleanup;
+ }
+ }
+
ret = 0;
--
1.7.6