Map DHCPv4 options to DHCPv6 where applicable.

This makes for an easier configuration.
Send the FQDN option by default.

diff --git a/dhcp6.c b/dhcp6.c
index 1de40b2e4f85386e60f391ab2fd9e507ed74be22..0b8edab5919e7f8a7e2b7932d89504651c2db9e4 100644 (file)
--- a/dhcp6.c
+++ b/dhcp6.c
@@ -130,6 +130,21 @@ const struct dhcp_opt dhcp6_opts[] = {
        { 0, 0, NULL }
 };
 
+struct dhcp_compat {
+       uint8_t dhcp_opt;
+       uint16_t dhcp6_opt;
+};
+
+const struct dhcp_compat dhcp_compats[] = {
+       { DHO_DNSSERVER,        D6_OPTION_DNS_SERVERS },
+       { DHO_HOSTNAME,         D6_OPTION_FQDN },
+       { DHO_DNSDOMAIN,        D6_OPTION_FQDN },
+       { DHO_NISSERVER,        D6_OPTION_NIS_SERVERS },
+       { DHO_FQDN,             D6_OPTION_FQDN },
+       { DHO_DNSSEARCH,        D6_OPTION_DOMAIN_LIST },
+       { 0, 0 }
+};
+
 #if DEBUG_MEMORY
 static void
 dhcp6_cleanup(void)
@@ -356,7 +371,7 @@ dhcp6_makemessage(struct interface *ifp)
        ssize_t len, ml;
        size_t l;
        uint8_t u8;
-       uint16_t *u16;
+       uint16_t *u16, n_options;
        const struct if_options *ifo;
        const struct dhcp_opt *opt;
        uint8_t IA, *p;
@@ -372,20 +387,20 @@ dhcp6_makemessage(struct interface *ifp)
 
        /* Work out option size first */
        ifo = ifp->options;
+       n_options = 0;
        len = 0;
        si = NULL;
        if (state->state != DH6S_RELEASE) {
                for (opt = dhcp6_opts; opt->option; opt++) {
                        if (opt->type & REQUEST ||
                            has_option_mask(ifo->requestmask6, opt->option))
+                       {
+                               n_options++;
                                len += sizeof(*u16);
+                       }
                }
-               if (len == 0) {
-                       len = sizeof(*u16) * 3;
-                       if (ifo->fqdn != FQDN_DISABLE)
-                               len += sizeof(*u16);
-               }
-               len += sizeof(*o);
+               if (len)
+                       len += sizeof(*o);
 
                if (ifo->fqdn != FQDN_DISABLE) {
                        if (ifo->hostname[0] == '\0')
@@ -601,29 +616,23 @@ dhcp6_makemessage(struct interface *ifp)
                                *p = 0x04;
                        o->len = htons(++o->len);
                }
-               o = D6_NEXT_OPTION(o);
-               o->code = htons(D6_OPTION_ORO);
-               o->len = 0;
-               u16 = (uint16_t *)(void *)D6_OPTION_DATA(o);
-               for (opt = dhcp6_opts; opt->option; opt++) {
-                       if (opt->type & REQUEST ||
-                           has_option_mask(ifo->requestmask6, opt->option))
-                       {
-                               *u16++ = htons(opt->option);
-                               o->len += sizeof(*u16);
-                       }
-               }
-               if (o->len == 0) {
-                       *u16++ = htons(D6_OPTION_UNICAST);
-                       *u16++ = htons(D6_OPTION_DNS_SERVERS);
-                       *u16++ = htons(D6_OPTION_DOMAIN_LIST);
-                       o->len = sizeof(*u16) * 3;
-                       if (ifo->fqdn != FQDN_DISABLE) {
-                               *u16++ = htons(D6_OPTION_FQDN);
-                               o->len += sizeof(*u16);
+
+               if (n_options) {
+                       o = D6_NEXT_OPTION(o);
+                       o->code = htons(D6_OPTION_ORO);
+                       o->len = 0;
+                       u16 = (uint16_t *)(void *)D6_OPTION_DATA(o);
+                       for (opt = dhcp6_opts; opt->option; opt++) {
+                               if (opt->type & REQUEST ||
+                                   has_option_mask(ifo->requestmask6,
+                                       opt->option))
+                               {
+                                       *u16++ = htons(opt->option);
+                                       o->len += sizeof(*u16);
+                               }
                        }
+                       o->len = htons(o->len);
                }
-               o->len = htons(o->len);
        }
 
        return 0;
@@ -2181,9 +2190,28 @@ static void
 dhcp6_start1(void *arg)
 {
        struct interface *ifp = arg;
+       struct if_options *ifo = ifp->options;
        struct dhcp6_state *state;
+       size_t i;
+       const struct dhcp_compat *dhc;
 
        state = D6_STATE(ifp);
+       /* Match any DHCPv4 opton to DHCPv6 options if given for easy
+        * configuration */
+       for (i = 0; i < sizeof(ifo->requestmask6); i++) {
+               if (ifo->requestmask6[i] != '\0')
+                       break;
+       }
+       if (i == sizeof(ifo->requestmask6)) {
+               for (dhc = dhcp_compats; dhc->dhcp_opt; dhc++) {
+                       if (has_option_mask(ifo->requestmask, dhc->dhcp_opt))
+                               add_option_mask(ifo->requestmask6,
+                                   dhc->dhcp6_opt);
+               }
+               if (ifo->fqdn != FQDN_DISABLE)
+                       add_option_mask(ifo->requestmask6, D6_OPTION_FQDN);
+       }
+
        syslog(LOG_INFO, "%s: %s", ifp->name,
            state->state == DH6S_INFORM ?
            "requesting DHCPv6 information" :

diff --git a/dhcpcd.conf b/dhcpcd.conf
index e7bc1167ede2c530c2a85877b687cf3703027d65..1f5b4adbc7ef95c4047c9c846264770c9f7b3fae 100644 (file)
--- a/dhcpcd.conf
+++ b/dhcpcd.conf
@@ -1,9 +1,15 @@
 # A sample configuration for dhcpcd.
 # See dhcpcd.conf(5) for details.
 
-# Inform the DHCP server of our hostname for DDNS.
+# Inform the DHCPv4 server of our hostname for DDNS.
+# This has been superceded by the FQDN option below, but is included
+# by default for servers which do not understand it.
 hostname
 
+# Inform the DHCP server of our hostname for DDNS
+# and/or query for what it should be.
+fqdn
+
 # Use the hardware address of the interface for the Client ID.
 #clientid
 # or

diff --git a/dhcpcd.conf.5.in b/dhcpcd.conf.5.in
index 4b0d5c0ca6667fe29fc9dd55987f77c207c7bfa4..0ef7984032db0b262921d6bc9a9a06dacceb8c6b 100644 (file)
--- a/dhcpcd.conf.5.in
+++ b/dhcpcd.conf.5.in
@@ -259,7 +259,15 @@ from the server.
 It can be a variable to be used in
 .Xr dhcpcd-run-hooks 8
 or the numerical value.
-You can specify more options separated by commas, spaces or more option lines.
+You can specify more
+.Ar option Ns s
+separated by commas, spaces or more
+.Ic option
+lines.
+Prepend dhcp6_ to
+.Ar option
+to request a DHCPv6 option.
+DHCPv4 options are mapped to DHCPv6 where applicable.
 .It Ic nooption Ar option
 Remove the option from the DHCP message.
 This should only be used when a DHCP server sends a non requested option