network: Fix split in `SendOption=` on client and server

When specifying `DHCPv4.SendOption=`, it is used by systemd-networkd to
set the value of that option within the DHCP request that is sent out.
This differs to setting `DHCPServer.SendOption=`, which will place all
the options together as suboptions into the vendor-specific information
(code 43) option.

This commit adds two new config options, `DHCPv4.SendVendorOption=` and
`DHCPServer.SendVendorOption=`. These both have the behaviour of the old
`DHCPServer.SendOption=` flag, and set the value of the suboption in the
vendor-specific information option.

The behaviour of `DHCPServer.SendOption=` is then changed to reflect
that of `DHCPv4.SendOption=`. It will set the value of the corresponding
option in the DHCP request.

1 files changed, 36 insertions, 6 deletions

diff --git a/src/libsystemd-network/sd-dhcp-client.c b/src/libsystemd-network/sd-dhcp-client.c
index 4122d08d96..82553e79ca 100644
--- a/src/libsystemd-network/sd-dhcp-client.c
+++ b/src/libsystemd-network/sd-dhcp-client.c
@@ -89,7 +89,8 @@ struct sd_dhcp_client {
         usec_t start_time;
         uint64_t attempt;
         uint64_t max_attempts;
-        OrderedHashmap *options;
+        OrderedHashmap *extra_options;
+        OrderedHashmap *vendor_options;
         usec_t request_sent;
         sd_event_source *timeout_t1;
         sd_event_source *timeout_t2;
@@ -540,17 +541,17 @@ int sd_dhcp_client_set_max_attempts(sd_dhcp_client *client, uint64_t max_attempt
         return 0;
 }
 
-int sd_dhcp_client_set_dhcp_option(sd_dhcp_client *client, sd_dhcp_option *v) {
+int sd_dhcp_client_add_option(sd_dhcp_client *client, sd_dhcp_option *v) {
         int r;
 
         assert_return(client, -EINVAL);
         assert_return(v, -EINVAL);
 
-        r = ordered_hashmap_ensure_allocated(&client->options, &dhcp_option_hash_ops);
+        r = ordered_hashmap_ensure_allocated(&client->extra_options, &dhcp_option_hash_ops);
         if (r < 0)
                 return r;
 
-        r = ordered_hashmap_put(client->options, UINT_TO_PTR(v->option), v);
+        r = ordered_hashmap_put(client->extra_options, UINT_TO_PTR(v->option), v);
         if (r < 0)
                 return r;
 
@@ -558,6 +559,25 @@ int sd_dhcp_client_set_dhcp_option(sd_dhcp_client *client, sd_dhcp_option *v) {
         return 0;
 }
 
+int sd_dhcp_client_add_vendor_option(sd_dhcp_client *client, sd_dhcp_option *v) {
+        int r;
+
+        assert_return(client, -EINVAL);
+        assert_return(v, -EINVAL);
+
+        r = ordered_hashmap_ensure_allocated(&client->vendor_options, &dhcp_option_hash_ops);
+        if (r < 0)
+                return -ENOMEM;
+
+        r = ordered_hashmap_put(client->vendor_options, v, v);
+        if (r < 0)
+                return r;
+
+        sd_dhcp_option_ref(v);
+
+        return 1;
+}
+
 int sd_dhcp_client_get_lease(sd_dhcp_client *client, sd_dhcp_lease **ret) {
         assert_return(client, -EINVAL);
 
@@ -884,13 +904,22 @@ static int client_send_discover(sd_dhcp_client *client) {
                         return r;
         }
 
-        ORDERED_HASHMAP_FOREACH(j, client->options, i) {
+        ORDERED_HASHMAP_FOREACH(j, client->extra_options, i) {
                 r = dhcp_option_append(&discover->dhcp, optlen, &optoffset, 0,
                                        j->option, j->length, j->data);
                 if (r < 0)
                         return r;
         }
 
+        if (!ordered_hashmap_isempty(client->vendor_options)) {
+                r = dhcp_option_append(
+                                &discover->dhcp, optlen, &optoffset, 0,
+                                SD_DHCP_OPTION_VENDOR_SPECIFIC,
+                                ordered_hashmap_size(client->vendor_options), client->vendor_options);
+                if (r < 0)
+                        return r;
+        }
+
         r = dhcp_option_append(&discover->dhcp, optlen, &optoffset, 0,
                                SD_DHCP_OPTION_END, 0, NULL);
         if (r < 0)
@@ -2073,7 +2102,8 @@ static sd_dhcp_client *dhcp_client_free(sd_dhcp_client *client) {
         free(client->hostname);
         free(client->vendor_class_identifier);
         client->user_class = strv_free(client->user_class);
-        ordered_hashmap_free(client->options);
+        ordered_hashmap_free(client->extra_options);
+        ordered_hashmap_free(client->vendor_options);
         return mfree(client);
 }