Re: [libvirt] [PATCHv2 2/5] domifaddr: Implement the remote protocol

15 Aug 2013

On Thu, Aug 15, 2013 at 02:24:27AM +0530, nehaljwani wrote:
...
Implement RPC calls for virDomainInterfacesAddresses
daemon/remote.c
   * Define remoteSerializeDomainInterfacePtr, remoteDispatchDomainInterfacesAddresses
src/remote/remote_driver.c
   * Define remoteDomainInterfacesAddresses
src/remote/remote_protocol.x
   * New RPC procedure: REMOTE_PROC_DOMAIN_INTERFACES_ADDRESSES
   * Define structs remote_domain_ip_addr, remote_domain_interface,
     remote_domain_interfaces_addresses_args, remote_domain_interfaces_addresses_ret
src/remote_protocol-structs
   * New structs added
---
 daemon/remote.c              | 122 +++++++++++++++++++++++++++++++++++++++++++
 src/remote/remote_driver.c   |  88 +++++++++++++++++++++++++++++++
 src/remote/remote_protocol.x |  30 ++++++++++-
 src/remote_protocol-structs  |  24 +++++++++
 4 files changed, 263 insertions(+), 1 deletion(-)

diff --git a/daemon/remote.c b/daemon/remote.c
index 03d5557..9d8651c 100644
--- a/daemon/remote.c
+++ b/daemon/remote.c
@@ -5025,7 +5025,129 @@ cleanup:
     return rv;
 }
+static int
+remoteSerializeDomainInterfacePtr(virDomainInterfacePtr ifaces,
+                                  unsigned int ifaces_count,
+                                  remote_domain_interfaces_addresses_ret *ret)
+{
+    size_t i, j;
+
+    if (VIR_ALLOC_N(ret->ifaces.ifaces_val, ifaces_count) < 0)
+        return -1;
You *must* check upper bound of ifaces_count before allocating memory - this
value is untrusted data.
...
+
+    ret->ifaces.ifaces_len = ifaces_count;
+
+    for (i = 0; i < ifaces_count; i++) {
+        virDomainInterfacePtr iface = &(ifaces[i]);
+        remote_domain_interface *iface_ret = &(ret->ifaces.ifaces_val[i]);
+
+        if ((VIR_STRDUP(iface_ret->name, iface->name)) < 0)
+            goto no_memory;
+
+        if (iface->hwaddr) {
+            char **hwaddr_p = NULL;
+            if (VIR_ALLOC(hwaddr_p) < 0)
+                goto no_memory;
+            if (VIR_STRDUP(*hwaddr_p, iface->hwaddr) < 0) {
+                VIR_FREE(hwaddr_p);
+                goto no_memory;
+            }
+
+            iface_ret->hwaddr = hwaddr_p;
+        }
+
+        if (VIR_ALLOC_N(iface_ret->ip_addrs.ip_addrs_val,
+                        iface->ip_addrs_count) < 0)
+            goto no_memory;
Again  ip_addrs_count is untrusted data so must have an upper
bound checked.
...
+
+        iface_ret->ip_addrs.ip_addrs_len = iface->ip_addrs_count;
+
+        for (j = 0; j < iface->ip_addrs_count; j++) {
+            virDomainIPAddressPtr ip_addr = &(iface->ip_addrs[j]);
+            remote_domain_ip_addr *ip_addr_ret =
+                &(iface_ret->ip_addrs.ip_addrs_val[j]);
+
+            if (VIR_STRDUP(ip_addr_ret->addr, ip_addr->addr) < 0)
+                goto no_memory;
+
+            ip_addr_ret->prefix = ip_addr->prefix;
+            ip_addr_ret->type = ip_addr->type;
+        }
+    }
+
+    return 0;
+
+no_memory:
+    if (ret->ifaces.ifaces_val) {
+        for (i = 0; i < ifaces_count; i++) {
+            remote_domain_interface *iface_ret = &(ret->ifaces.ifaces_val[i]);
+            VIR_FREE(iface_ret->name);
+            VIR_FREE(iface_ret->hwaddr);
+            for (j = 0; j < iface_ret->ip_addrs.ip_addrs_len; j++) {
+                remote_domain_ip_addr *ip_addr =
+                    &(iface_ret->ip_addrs.ip_addrs_val[j]);
+                VIR_FREE(ip_addr->addr);
+            }
+            VIR_FREE(iface_ret);
+        }
+        VIR_FREE(ret->ifaces.ifaces_val);
+    }
+    return -1;
+}
+
+static int
+remoteDispatchDomainInterfacesAddresses(
+    virNetServerPtr server ATTRIBUTE_UNUSED,
+    virNetServerClientPtr client,
+    virNetMessagePtr msg ATTRIBUTE_UNUSED,
+    virNetMessageErrorPtr rerr,
+    remote_domain_interfaces_addresses_args *args,
+    remote_domain_interfaces_addresses_ret *ret)
+{
+    int rv = -1;
+    virDomainPtr dom = NULL;
+    virDomainInterfacePtr ifaces = NULL;
+    unsigned int ifaces_count = 0;
+    struct daemonClientPrivate *priv =
+        virNetServerClientGetPrivateData(client);
+
+    if (!priv->conn) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("connection not open"));
+        goto cleanup;
+    }
+
+    if (!(dom = get_nonnull_domain(priv->conn, args->dom)))
+        goto cleanup;
+
+    if (virDomainInterfacesAddresses(dom, &ifaces,
+                                     &ifaces_count, args->flags) < 0)
+        goto cleanup;
+
+    if (remoteSerializeDomainInterfacePtr(ifaces, ifaces_count, ret) < 0)
+        goto cleanup;
+
+    rv = 0;
+
+cleanup:
+    if (rv < 0)
+        virNetMessageSaveError(rerr);
+    if (dom)
+        virDomainFree(dom);
+    if (ifaces) {
+        size_t i, j;
+
+        for (i = 0; i < ifaces_count; i++) {
+            VIR_FREE(ifaces[i].name);
+            VIR_FREE(ifaces[i].hwaddr);
+            for (j = 0; j < ifaces[i].ip_addrs_count; j++)
+                VIR_FREE(ifaces[i].ip_addrs[j].addr);
+            VIR_FREE(ifaces[i].ip_addrs);
+        }
+        VIR_FREE(ifaces);
+    }
+    return rv;
+}
/*----- Helpers. -----*/

...
+cleanup:
+    if (rv < 0) {
+        for (i = 0; i < *ifaces_count; i++) {
+            VIR_FREE((*ifaces)[i].name);
+            VIR_FREE((*ifaces)[i].hwaddr);
+            for (j = 0; j < (*ifaces)[i].ip_addrs_count; j++)
+                VIR_FREE((*ifaces)[i].ip_addrs[j].addr);
+            VIR_FREE((*ifaces)[i].ip_addrs);
+        }
+        VIR_FREE(*ifaces);
This horrible code is repeated soo many times - just reinforces my
point on the previous patch about providing a function to hide this.
...
+    }
+    xdr_free((xdrproc_t)xdr_remote_domain_interfaces_addresses_ret,
+             (char *) &ret);
+done:
+    remoteDriverUnlock(priv);
+    return rv;
+}
+
 static void
 remoteDomainEventQueue(struct private_data *priv, virDomainEventPtr event)
 {
@@ -6811,6 +6898,7 @@ static virDriver remote_driver = {
     .domainMigratePerform3Params = remoteDomainMigratePerform3Params, /* 1.1.0 */
     .domainMigrateFinish3Params = remoteDomainMigrateFinish3Params, /* 1.1.0 */
     .domainMigrateConfirm3Params = remoteDomainMigrateConfirm3Params, /* 1.1.0 */
+    .domainInterfacesAddresses = remoteDomainInterfacesAddresses, /* 1.1.2 */
 };
static virNetworkDriver network_driver = {
diff --git a/src/remote/remote_protocol.x b/src/remote/remote_protocol.x
index 7cfebdf..06929e7 100644
--- a/src/remote/remote_protocol.x
+++ b/src/remote/remote_protocol.x
@@ -2837,6 +2837,27 @@ struct remote_domain_event_device_removed_msg {
     remote_nonnull_string devAlias;
 };
+struct remote_domain_ip_addr {
+    int type;
+    remote_nonnull_string addr;
+    int prefix;
+};
+
+struct remote_domain_interface {
+    remote_nonnull_string name;
+    remote_string hwaddr;
+    remote_domain_ip_addr ip_addrs<>;
Use of <> *NOT* allowed - this is a security flaw allowing the client
to trigger DOS on libvirtd allocating memory. Follow the examples of
other APis which set an explicit limit.
...
+};
+
+struct remote_domain_interfaces_addresses_args {
+    remote_nonnull_domain dom;
+    unsigned int flags;
+};
+
+struct remote_domain_interfaces_addresses_ret {
+    remote_domain_interface ifaces<>;
Again, this is flawed.

Daniel
-- 
|: http://berrange.com      -o-    http://www.flickr.com/photos/dberrange/ :|
|: http://libvirt.org              -o-             http://virt-manager.org :|
|: http://autobuild.org       -o-         http://search.cpan.org/~danberr/ :|
|: http://entangle-photo.org       -o-       http://live.gnome.org/gtk-vnc :|

    

Re: [libvirt] [PATCHv2 2/5] domifaddr: Implement the remote protocol

Daniel P. Berrange