[Qemu-devel] [PATCH] mark nic as trusted

[Gleb Natapov <gleb@redhat.com>]

This patch allows to mark specific nic as trusted by adding special
PCI capability. "Trusted" means that it is used for communication
between host and guest and no malicious entity can inject traffic
to the nic.

Signed-off-by: Gleb Natapov <gleb@redhat.com>

diff --git a/hw/e1000.c b/hw/e1000.c
index c326671..ea4d824 100644
--- a/hw/e1000.c
+++ b/hw/e1000.c
@@ -1045,6 +1045,9 @@ pci_e1000_init(PCIBus *bus, NICInfo *nd, int devfn)
 
     pci_conf[0x3d] = 1; // interrupt pin 0
 
+    if (nd->secure_cookie[0])
+        pci_add_capability(&d->dev, 0x0f, 0xf0, nd->secure_cookie, 14);
+
     d->mmio_index = cpu_register_io_memory(0, e1000_mmio_read,
             e1000_mmio_write, d);
 
diff --git a/hw/eepro100.c b/hw/eepro100.c
index cb3ca09..654b389 100644
--- a/hw/eepro100.c
+++ b/hw/eepro100.c
@@ -1754,6 +1754,9 @@ static void nic_init(PCIBus * bus, NICInfo * nd,
 
     pci_reset(s);
 
+    if (nd->secure_cookie[0])
+        pci_add_capability(&d->dev, 0x0f, 0xf0, nd->secure_cookie, 14);
+
     /* Add 64 * 2 EEPROM. i82557 and i82558 support a 64 word EEPROM,
      * i82559 and later support 64 or 256 word EEPROM. */
     s->eeprom = eeprom93xx_new(EEPROM_SIZE);
diff --git a/hw/ne2000.c b/hw/ne2000.c
index 3f0ccf5..c3f4e22 100644
--- a/hw/ne2000.c
+++ b/hw/ne2000.c
@@ -806,6 +806,10 @@ void pci_ne2000_init(PCIBus *bus, NICInfo *nd, int devfn)
 
     pci_register_io_region(&d->dev, 0, 0x100,
                            PCI_ADDRESS_SPACE_IO, ne2000_map);
+
+    if (nd->secure_cookie[0])
+        pci_add_capability(&d->dev, 0x0f, 0xf0, nd->secure_cookie, 14);
+
     s = &d->ne2000;
     s->irq = d->dev.irq[0];
     s->pci_dev = (PCIDevice *)d;
diff --git a/hw/pci.c b/hw/pci.c
index 8252d21..05bfa4b 100644
--- a/hw/pci.c
+++ b/hw/pci.c
@@ -536,6 +536,23 @@ static void pci_set_irq(void *opaque, int irq_num, int level)
     bus->set_irq(bus->irq_opaque, irq_num, bus->irq_count[irq_num] != 0);
 }
 
+int pci_add_capability(PCIDevice *d, uint8_t cap_id, uint8_t off, uint8_t *buf,
+        int len)
+{
+    uint16_t status = le16_to_cpu(*(uint16_t*)(d->config + 0x06));
+
+    if (off + len + 2 > 0x100 || off < 0x40)
+        return -1;
+
+    d->config[0x06] = cpu_to_le16(status | 0x10);
+    d->config[off] = cap_id;
+    d->config[off + 1] = d->config[0x34];
+    d->config[0x34] = off;
+    memcpy(d->config + off + 2, buf, len);
+
+    return 0;
+}
+
 /***********************************************************/
 /* monitor info on PCI */
 
diff --git a/hw/pci.h b/hw/pci.h
index 3b1caf5..87132ca 100644
--- a/hw/pci.h
+++ b/hw/pci.h
@@ -117,6 +117,8 @@ typedef void (*pci_set_irq_fn)(qemu_irq *pic, int irq_num, int level);
 typedef int (*pci_map_irq_fn)(PCIDevice *pci_dev, int irq_num);
 PCIBus *pci_register_bus(pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
                          qemu_irq *pic, int devfn_min, int nirq);
+int pci_add_capability(PCIDevice *d, uint8_t cap_id, uint8_t off, uint8_t *buf,
+        int len);
 
 void pci_nic_init(PCIBus *bus, NICInfo *nd, int devfn);
 void pci_data_write(void *opaque, uint32_t addr, uint32_t val, int len);
diff --git a/hw/pcnet.c b/hw/pcnet.c
index 30c453c..990afb2 100644
--- a/hw/pcnet.c
+++ b/hw/pcnet.c
@@ -2024,6 +2024,9 @@ void pci_pcnet_init(PCIBus *bus, NICInfo *nd, int devfn)
     pci_conf[0x3e] = 0x06;
     pci_conf[0x3f] = 0xff;
 
+    if (nd->secure_cookie[0])
+        pci_add_capability(&d->dev, 0x0f, 0xf0, nd->secure_cookie, 14);
+
     /* Handler for memory-mapped I/O */
     d->mmio_index =
       cpu_register_io_memory(0, pcnet_mmio_read, pcnet_mmio_write, d);
diff --git a/hw/rtl8139.c b/hw/rtl8139.c
index c3ab854..6e4c44f 100644
--- a/hw/rtl8139.c
+++ b/hw/rtl8139.c
@@ -3423,6 +3423,9 @@ void pci_rtl8139_init(PCIBus *bus, NICInfo *nd, int devfn)
     pci_conf[0x3d] = 1;    /* interrupt pin 0 */
     pci_conf[0x34] = 0xdc;
 
+    if (nd->secure_cookie[0])
+        pci_add_capability(&d->dev, 0x0f, 0xf0, nd->secure_cookie, 14);
+
     s = &d->rtl8139;
 
     /* I/O handler for memory-mapped I/O */
diff --git a/hw/virtio-net.c b/hw/virtio-net.c
index 1f45b2d..186c6bd 100644
--- a/hw/virtio-net.c
+++ b/hw/virtio-net.c
@@ -309,6 +309,9 @@ PCIDevice *virtio_net_init(PCIBus *bus, NICInfo *nd, int devfn)
     if (!n)
         return NULL;
 
+    if (nd->secure_cookie[0])
+        pci_add_capability(&n->vdev.pci_dev, 0x0f, 0xf0, nd->secure_cookie, 14);
+
     n->vdev.get_config = virtio_net_update_config;
     n->vdev.get_features = virtio_net_get_features;
     n->vdev.set_features = virtio_net_set_features;
diff --git a/net.c b/net.c
index 6af4255..000768f 100644
--- a/net.c
+++ b/net.c
@@ -1474,6 +1474,11 @@ int net_client_init(const char *device, const char *p)
         if (get_param_value(buf, sizeof(buf), "model", p)) {
             nd->model = strdup(buf);
         }
+        if (get_param_value(buf, sizeof(buf), "trusted", p)) {
+            strncpy(nd->secure_cookie, buf, sizeof(nd->secure_cookie));
+        } else {
+            nd->secure_cookie[0] = NULL;
+        }
         nd->vlan = vlan;
         nb_nics++;
         vlan->nb_guest_devs++;
diff --git a/net.h b/net.h
index 31c7a30..e57e6e5 100644
--- a/net.h
+++ b/net.h
@@ -50,6 +50,7 @@ struct NICInfo {
     uint8_t macaddr[6];
     const char *model;
     VLANState *vlan;
+    uint8_t secure_cookie[14];
 };
 
 extern int nb_nics;
--
			Gleb.