network: DHCPv6 - Add support to send vendor class information

Frame 1: 177 bytes on wire (1416 bits), 177 bytes captured (1416 bits) on interface veth-peer, id 0
Ethernet II, Src: 1e:04:f8:b8:2f:d4 (1e:04:f8:b8:2f:d4), Dst: IPv6mcast_01:00:02 (33:33:00:01:00:02)
Internet Protocol Version 6, Src: fe80::1c04:f8ff:feb8:2fd4, Dst: ff02::1:2
User Datagram Protocol, Src Port: 546, Dst Port: 547
DHCPv6
    Message type: Solicit (1)
    Transaction ID: 0x5ca46b
    Rapid Commit
    Identity Association for Non-temporary Address
    Fully Qualified Domain Name
    Vendor Class
        Option: Vendor Class (16)
        Length: 23
        Value: 0000ab11000048656c6c6f3a686f773a6172653a796f75
        Enterprise ID: Tom Gundersen (systemd) (43793)
        vendor-class-data: Hello:how:are:you
    Identity Association for Prefix Delegation
    Option Request
    Client Identifier
    Elapsed time

man/systemd.network.xml

@@ -1788,6 +1788,17 @@
             currently NUL bytes are not allowed.</para>
           </listitem>
         </varlistentry>
+
+        <varlistentry>
+          <term><varname>VendorClass=</varname></term>
+          <listitem>
+            <para>A DHCPv6 client can use VendorClass option to identify the vendor that
+            manufactured the hardware on which the client is running. The information
+            contained in the data area of this option is contained in one or more opaque
+            fields that identify details of the hardware configuration. Takes a
+            whitespace-separated list of strings.</para>
+          </listitem>
+        </varlistentry>
       </variablelist>
   </refsect1>
 

src/libsystemd-network/sd-dhcp6-client.c

@@ -381,7 +381,7 @@ int sd_dhcp6_client_set_request_mud_url(sd_dhcp6_client *client, const char *mud
         assert_return(client, -EINVAL);
         assert_return(client->state == DHCP6_STATE_STOPPED, -EBUSY);
         assert_return(mudurl, -EINVAL);
-        assert_return(strlen(mudurl) <= UINT8_MAX, -EINVAL);
+        assert_return(strlen(mudurl) <= 255, -EINVAL);
         assert_return(http_url_is_valid(mudurl), -EINVAL);
 
         return free_and_strdup(&client->mudurl, mudurl);

src/network/networkd-dhcp-common.c

@@ -329,6 +329,59 @@ int config_parse_dhcp_user_class(
         return 0;
 }
 
+int config_parse_dhcp_vendor_class(
+                const char *unit,
+                const char *filename,
+                unsigned line,
+                const char *section,
+                unsigned section_line,
+                const char *lvalue,
+                int ltype,
+                const char *rvalue,
+                void *data,
+                void *userdata) {
+        char ***l = data;
+        int r;
+
+        assert(l);
+        assert(lvalue);
+        assert(rvalue);
+
+        if (isempty(rvalue)) {
+                *l = strv_free(*l);
+                return 0;
+        }
+
+        for (;;) {
+                _cleanup_free_ char *w = NULL;
+
+                r = extract_first_word(&rvalue, &w, NULL, EXTRACT_CUNESCAPE|EXTRACT_UNQUOTE);
+                if (r == -ENOMEM)
+                        return log_oom();
+                if (r < 0) {
+                        log_syntax(unit, LOG_ERR, filename, line, r,
+                                   "Failed to split vendor classes option, ignoring: %s", rvalue);
+                        break;
+                }
+                if (r == 0)
+                        break;
+
+                if (strlen(w) > UINT8_MAX) {
+                        log_syntax(unit, LOG_ERR, filename, line, 0,
+                                   "%s length is not in the range 1-255, ignoring.", w);
+                        continue;
+                }
+
+                r = strv_push(l, w);
+                if (r < 0)
+                        return log_oom();
+
+                w = NULL;
+        }
+
+        return 0;
+}
+
 int config_parse_dhcp6_mud_url(
                 const char *unit,
                 const char *filename,

src/network/networkd-dhcp-common.h

@@ -51,5 +51,6 @@ CONFIG_PARSER_PROTOTYPE(config_parse_section_route_table);
 CONFIG_PARSER_PROTOTYPE(config_parse_dhcp6_pd_hint);
 CONFIG_PARSER_PROTOTYPE(config_parse_dhcp6_mud_url);
 CONFIG_PARSER_PROTOTYPE(config_parse_dhcp_user_class);
+CONFIG_PARSER_PROTOTYPE(config_parse_dhcp_vendor_class);
 CONFIG_PARSER_PROTOTYPE(config_parse_dhcp_send_option);
 CONFIG_PARSER_PROTOTYPE(config_parse_dhcp_request_options);

src/network/networkd-dhcp6.c

@@ -712,6 +712,12 @@ int dhcp6_configure(Link *link) {
                         return log_link_error_errno(link, r, "DHCP6 CLIENT: Failed to set user class: %m");
         }
 
+        if (link->network->dhcp6_vendor_class) {
+                r = sd_dhcp6_client_set_request_vendor_class(client, link->network->dhcp6_vendor_class);
+                if (r < 0)
+                        return log_link_error_errno(link, r, "DHCP6 CLIENT: Failed to set vendor class: %m");
+        }
+
         r = sd_dhcp6_client_set_callback(client, dhcp6_handler, link);
         if (r < 0)
                 return log_link_error_errno(link, r, "DHCP6 CLIENT: Failed to set callback: %m");

src/network/networkd-network-gperf.gperf

@@ -195,6 +195,7 @@ DHCPv6.RapidCommit,                          config_parse_bool,
 DHCPv6.MUDURL,                               config_parse_dhcp6_mud_url,                               0,                             0
 DHCPv6.RequestOptions,                       config_parse_dhcp_request_options,                        AF_INET6,                      0
 DHCPv6.UserClass,                            config_parse_dhcp_user_class,                             AF_INET6,                      offsetof(Network, dhcp6_user_class)
+DHCPv6.VendorClass,                          config_parse_dhcp_vendor_class,                           0,                             offsetof(Network, dhcp6_vendor_class)
 DHCPv6.ForceDHCPv6PDOtherInformation,        config_parse_bool,                                        0,                             offsetof(Network, dhcp6_force_pd_other_information)
 DHCPv6.PrefixDelegationHint,                 config_parse_dhcp6_pd_hint,                               0,                             0
 DHCPv6.WithoutRA,                            config_parse_bool,                                        0,                             offsetof(Network, dhcp6_without_ra)

src/network/networkd-network.c

@@ -654,6 +654,7 @@ static Network *network_free(Network *network) {
         free(network->mac);
         free(network->dhcp6_mudurl);
         strv_free(network->dhcp6_user_class);
+        strv_free(network->dhcp6_vendor_class);
 
         if (network->dhcp_acd)
                 sd_ipv4acd_unref(network->dhcp_acd);

src/network/networkd-network.h

@@ -133,6 +133,7 @@ struct Network {
         uint8_t dhcp6_pd_length;
         char *dhcp6_mudurl;
         char **dhcp6_user_class;
+        char **dhcp6_vendor_class;
         struct in6_addr dhcp6_pd_address;
         OrderedHashmap *dhcp6_client_send_options;
         Set *dhcp6_request_options;

test/fuzz/fuzz-network-parser/directives.network

@@ -116,6 +116,7 @@ MUDURL=
 SendOption=
 RequestOptions=
 UserClass=
+VendorClass=
 [Route]
 Destination=
 Protocol=