From 383ebc46947b0119123880c1ff9ae345fdb8d5f6 Mon Sep 17 00:00:00 2001
From: Pieter Hollants <pieter@hollants.com>
Date: Thu, 21 Feb 2013 23:40:17 +0100
Subject: [PATCH] Add support for <option> tag in network config

This patch adds support for a new <option>-Tag in the <dhcp> block of
network configs, based on a subset of the fifth proposal by Laine
Stump in the mailing list discussion at
https://www.redhat.com/archives/libvir-list/2012-November/msg01054.html.
Any such defined option will result in a dhcp-option=<number>,"<value>"
statement in the generated dnsmasq configuration file.

Currently, DHCP options can be specified by number only and there is
no whitelisting or blacklisting of option numbers, which should
probably be added.

Signed-off-by: Pieter Hollants <pieter@hollants.com>
Signed-off-by: Laine Stump <laine@laine.org>
---
 docs/schemas/network.rng                      |  6 +++
 src/conf/network_conf.c                       | 48 +++++++++++++++++++
 src/conf/network_conf.h                       | 11 +++++
 src/network/bridge_driver.c                   | 17 +++++++
 tests/networkxml2confdata/nat-network.conf    |  5 ++
 tests/networkxml2confdata/nat-network.xml     |  5 ++
 tests/networkxml2xmlin/netboot-network.xml    |  1 +
 .../netboot-proxy-network.xml                 |  1 +
 tests/networkxml2xmlout/netboot-network.xml   |  1 +
 .../netboot-proxy-network.xml                 |  1 +
 10 files changed, 96 insertions(+)

diff --git a/docs/schemas/network.rng b/docs/schemas/network.rng
index 09d7c7350e..66f32a44df 100644
--- a/docs/schemas/network.rng
+++ b/docs/schemas/network.rng
@@ -293,6 +293,12 @@
                     </optional>
                   </element>
                 </optional>
+                <zeroOrMore>
+                  <element name="option">
+                    <attribute name="number"><ref name="uint8range"/></attribute>
+                    <attribute name="value"><text/></attribute>
+                  </element>
+                </zeroOrMore>
               </element>
             </optional>
           </element>
diff --git a/src/conf/network_conf.c b/src/conf/network_conf.c
index cdffd19585..34fd05abe7 100644
--- a/src/conf/network_conf.c
+++ b/src/conf/network_conf.c
@@ -776,6 +776,37 @@ cleanup:
     return ret;
 }
 
+static int
+virNetworkDHCPOptionDefParseXML(const char *networkName,
+                                xmlNodePtr node,
+                                virNetworkDHCPOptionDefPtr option)
+{
+    char *number = NULL;
+    int ret = -1;
+
+    if (!(number = virXMLPropString(node, "number"))) {
+        virReportError(VIR_ERR_XML_ERROR,
+                       _("Option definition in IPv4 network '%s' "
+                         "must have number attribute"),
+                       networkName);
+        goto cleanup;
+    }
+    if (virStrToLong_ui(number, NULL, 10, &option->number) < 0) {
+        virReportError(VIR_ERR_XML_ERROR,
+                       _("Malformed <option> number attribute: %s"),
+                       number);
+        goto cleanup;
+    }
+    option->value = virXMLPropString(node, "value");
+
+    ret = 0;
+
+cleanup:
+    VIR_FREE(number);
+    return ret;
+}
+
+
 static int
 virNetworkDHCPDefParseXML(const char *networkName,
                           xmlNodePtr node,
@@ -837,6 +868,17 @@ virNetworkDHCPDefParseXML(const char *networkName,
             def->bootfile = file;
             def->bootserver = inaddr;
             VIR_FREE(server);
+        } else if (cur->type == XML_ELEMENT_NODE &&
+            xmlStrEqual(cur->name, BAD_CAST "option")) {
+            if (VIR_REALLOC_N(def->options, def->noptions + 1) < 0) {
+                virReportOOMError();
+                return -1;
+            }
+            if (virNetworkDHCPOptionDefParseXML(networkName, cur,
+                                                &def->options[def->noptions])) {
+                return -1;
+            }
+            def->noptions++;
         }
 
         cur = cur->next;
@@ -2171,6 +2213,12 @@ virNetworkIpDefFormat(virBufferPtr buf,
             virBufferAddLit(buf, "/>\n");
 
         }
+        for (ii = 0 ; ii < def->noptions ; ii++) {
+            virBufferAsprintf(buf, "<option number='%u'",
+                              def->options[ii].number);
+            virBufferEscapeString(buf, " value='%s'", def->options[ii].value);
+            virBufferAddLit(buf, "/>\n");
+        }
 
         virBufferAdjustIndent(buf, -2);
         virBufferAddLit(buf, "</dhcp>\n");
diff --git a/src/conf/network_conf.h b/src/conf/network_conf.h
index d5de7d138e..e7a4f95f2b 100644
--- a/src/conf/network_conf.h
+++ b/src/conf/network_conf.h
@@ -70,6 +70,13 @@ struct _virNetworkDHCPHostDef {
     virSocketAddr ip;
 };
 
+typedef struct _virNetworkDHCPOptionDef virNetworkDHCPOptionDef;
+typedef virNetworkDHCPOptionDef *virNetworkDHCPOptionDefPtr;
+struct _virNetworkDHCPOptionDef {
+    unsigned int number;
+    char *value;
+};
+
 typedef struct _virNetworkDNSTxtDef virNetworkDNSTxtDef;
 typedef virNetworkDNSTxtDef *virNetworkDNSTxtDefPtr;
 struct _virNetworkDNSTxtDef {
@@ -129,9 +136,13 @@ struct _virNetworkIpDef {
     size_t nhosts;              /* Zero or more dhcp hosts */
     virNetworkDHCPHostDefPtr hosts;
 
+    size_t noptions;            /* Zero or more additional dhcp options */
+    virNetworkDHCPOptionDefPtr options;
+
     char *tftproot;
     char *bootfile;
     virSocketAddr bootserver;
+
    };
 
 typedef struct _virNetworkForwardIfDef virNetworkForwardIfDef;
diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c
index d7f6df9f15..0c3f778da8 100644
--- a/src/network/bridge_driver.c
+++ b/src/network/bridge_driver.c
@@ -926,6 +926,23 @@ networkDnsmasqConfContents(virNetworkObjPtr network,
                     virBufferAsprintf(&configbuf, "dhcp-boot=%s\n", ipdef->bootfile);
                 }
             }
+
+            for (r = 0 ; r < ipdef->noptions ; r++) {
+                virBufferAsprintf(&configbuf, "dhcp-option=%u",
+                                  ipdef->options[r].number);
+                /* value is optional, and only needs quoting if it contains spaces */
+                if (ipdef->options[r].value) {
+                    const char *quote = "";
+
+                    if (strchr(ipdef->options[r].value, ' ') ||
+                        strchr(ipdef->options[r].value, '\\')) {
+                        quote = "\"";
+                    }
+                    virBufferAsprintf(&configbuf, ",%s%s%s",
+                                      quote, ipdef->options[r].value, quote);
+                }
+                virBufferAddLit(&configbuf, "\n");
+            }
         }
         ipdef = (ipdef == ipv6def) ? NULL : ipv6def;
     }
diff --git a/tests/networkxml2confdata/nat-network.conf b/tests/networkxml2confdata/nat-network.conf
index beb714b134..ee41e2ae99 100644
--- a/tests/networkxml2confdata/nat-network.conf
+++ b/tests/networkxml2confdata/nat-network.conf
@@ -12,6 +12,11 @@ bind-dynamic
 interface=virbr0
 dhcp-range=192.168.122.2,192.168.122.254
 dhcp-no-override
+dhcp-option=42,192.168.122.20
+dhcp-option=23,50
+dhcp-option=40,libvirt
+dhcp-option=252,"\n"
+dhcp-option=253," leading and trailing spaces "
 dhcp-leasefile=/var/lib/libvirt/dnsmasq/default.leases
 dhcp-lease-max=253
 dhcp-hostsfile=/var/lib/libvirt/dnsmasq/default.hostsfile
diff --git a/tests/networkxml2confdata/nat-network.xml b/tests/networkxml2confdata/nat-network.xml
index eb71d9ea38..22ec533de4 100644
--- a/tests/networkxml2confdata/nat-network.xml
+++ b/tests/networkxml2confdata/nat-network.xml
@@ -8,6 +8,11 @@
       <range start='192.168.122.2' end='192.168.122.254' />
       <host mac='00:16:3e:77:e2:ed' name='a.example.com' ip='192.168.122.10' />
       <host mac='00:16:3e:3e:a9:1a' name='b.example.com' ip='192.168.122.11' />
+      <option number='42' value='192.168.122.20'/>
+      <option number='23' value='50'/>
+      <option number='40' value='libvirt'/>
+      <option number='252' value='\n'/>
+      <option number='253' value=' leading and trailing spaces '/>
     </dhcp>
   </ip>
   <ip family='ipv4' address='192.168.123.1' netmask='255.255.255.0'>
diff --git a/tests/networkxml2xmlin/netboot-network.xml b/tests/networkxml2xmlin/netboot-network.xml
index ed75663053..09c11d4957 100644
--- a/tests/networkxml2xmlin/netboot-network.xml
+++ b/tests/networkxml2xmlin/netboot-network.xml
@@ -9,6 +9,7 @@
     <dhcp>
       <range start="192.168.122.2" end="192.168.122.254" />
       <bootp file="pxeboot.img" />
+      <option number="252" value="\n"/>
     </dhcp>
   </ip>
 </network>
diff --git a/tests/networkxml2xmlin/netboot-proxy-network.xml b/tests/networkxml2xmlin/netboot-proxy-network.xml
index ecb6738694..77b353ddc5 100644
--- a/tests/networkxml2xmlin/netboot-proxy-network.xml
+++ b/tests/networkxml2xmlin/netboot-proxy-network.xml
@@ -8,6 +8,7 @@
     <dhcp>
       <range start="192.168.122.2" end="192.168.122.254" />
       <bootp file="pxeboot.img" server="10.20.30.40" />
+      <option number="252" value="\n"/>
     </dhcp>
   </ip>
 </network>
diff --git a/tests/networkxml2xmlout/netboot-network.xml b/tests/networkxml2xmlout/netboot-network.xml
index b8a4d996fb..f3a4c6bcfb 100644
--- a/tests/networkxml2xmlout/netboot-network.xml
+++ b/tests/networkxml2xmlout/netboot-network.xml
@@ -9,6 +9,7 @@
     <dhcp>
       <range start='192.168.122.2' end='192.168.122.254' />
       <bootp file='pxeboot.img' />
+      <option number='252' value='\n'/>
     </dhcp>
   </ip>
 </network>
diff --git a/tests/networkxml2xmlout/netboot-proxy-network.xml b/tests/networkxml2xmlout/netboot-proxy-network.xml
index e11c50b3ee..2c97bd0a81 100644
--- a/tests/networkxml2xmlout/netboot-proxy-network.xml
+++ b/tests/networkxml2xmlout/netboot-proxy-network.xml
@@ -8,6 +8,7 @@
     <dhcp>
       <range start='192.168.122.2' end='192.168.122.254' />
       <bootp file='pxeboot.img' server='10.20.30.40' />
+      <option number='252' value='\n'/>
     </dhcp>
   </ip>
 </network>