[systemd-devel] [PATCH 08/11] sd-dhcp6: Support deprecated SNTP Configuration Option

[Patrik Flykt]

Although the SNTP option specified in RFC 4075 has been deprecated, some
servers are still sending NTP information with this option. Use the SNTP
information provided only if the NTP option is not present.

Update the test case as SNTP information is also requested.
---
 src/libsystemd-network/dhcp6-lease-internal.h |  2 ++
 src/libsystemd-network/dhcp6-protocol.h       |  2 +-
 src/libsystemd-network/sd-dhcp6-client.c      |  8 ++++++
 src/libsystemd-network/sd-dhcp6-lease.c       | 36 +++++++++++++++++++++++++++
 src/libsystemd-network/test-dhcp6-client.c    |  2 +-
 5 files changed, 48 insertions(+), 2 deletions(-)

diff --git a/src/libsystemd-network/dhcp6-lease-internal.h b/src/libsystemd-network/dhcp6-lease-internal.h
index ac7f843..037f580 100644
--- a/src/libsystemd-network/dhcp6-lease-internal.h
+++ b/src/libsystemd-network/dhcp6-lease-internal.h
@@ -71,6 +71,8 @@ int dhcp6_lease_set_dns(sd_dhcp6_lease *lease, uint8_t *optval, size_t optlen);
 int dhcp6_lease_set_domains(sd_dhcp6_lease *lease, uint8_t *optval,
                             size_t optlen);
 int dhcp6_lease_set_ntp(sd_dhcp6_lease *lease, uint8_t *optval, size_t optlen);
+int dhcp6_lease_set_sntp(sd_dhcp6_lease *lease, uint8_t *optval,
+                         size_t optlen) ;
 
 int dhcp6_lease_new(sd_dhcp6_lease **ret);
 
diff --git a/src/libsystemd-network/dhcp6-protocol.h b/src/libsystemd-network/dhcp6-protocol.h
index 9330f23..b3a28f8 100644
--- a/src/libsystemd-network/dhcp6-protocol.h
+++ b/src/libsystemd-network/dhcp6-protocol.h
@@ -123,7 +123,7 @@ enum {
         DHCP6_OPTION_DNS_SERVERS                = 23,  /* RFC 3646 */
         DHCP6_OPTION_DOMAIN_LIST                = 24,  /* RFC 3646 */
 
-        DHCP6_OPTION_SNTP_SERVERS               = 31,  /* RFC 4075 */
+        DHCP6_OPTION_SNTP_SERVERS               = 31,  /* RFC 4075, deprecated */
 
         /* option code 35 is unassigned */
 
diff --git a/src/libsystemd-network/sd-dhcp6-client.c b/src/libsystemd-network/sd-dhcp6-client.c
index e6f0c79..ffab1e4 100644
--- a/src/libsystemd-network/sd-dhcp6-client.c
+++ b/src/libsystemd-network/sd-dhcp6-client.c
@@ -73,6 +73,7 @@ static const uint16_t default_req_opts[] = {
         DHCP6_OPTION_DNS_SERVERS,
         DHCP6_OPTION_DOMAIN_LIST,
         DHCP6_OPTION_NTP_SERVER,
+        DHCP6_OPTION_SNTP_SERVERS,
 };
 
 const char * dhcp6_message_type_table[_DHCP6_MESSAGE_MAX] = {
@@ -774,6 +775,13 @@ static int client_parse_message(sd_dhcp6_client *client,
                                 return r;
 
                         break;
+
+                case DHCP6_OPTION_SNTP_SERVERS:
+                        r = dhcp6_lease_set_sntp(lease, optval, optlen);
+                        if (r < 0)
+                                return r;
+
+                        break;
                 }
 
         }
diff --git a/src/libsystemd-network/sd-dhcp6-lease.c b/src/libsystemd-network/sd-dhcp6-lease.c
index 8631aab..f0494b3 100644
--- a/src/libsystemd-network/sd-dhcp6-lease.c
+++ b/src/libsystemd-network/sd-dhcp6-lease.c
@@ -257,6 +257,10 @@ int dhcp6_lease_set_ntp(sd_dhcp6_lease *lease, uint8_t *optval, size_t optlen)
         assert_return(lease, -EINVAL);
         assert_return(optval, -EINVAL);
 
+        free(lease->ntp);
+        lease->ntp_count = 0;
+        lease->ntp_allocated = 0;
+
         while ((r = dhcp6_option_parse(&optval, &optlen, &subopt, &sublen,
                                        &subval)) >= 0) {
                 int s;
@@ -299,6 +303,38 @@ int dhcp6_lease_set_ntp(sd_dhcp6_lease *lease, uint8_t *optval, size_t optlen)
         return 0;
 }
 
+int dhcp6_lease_set_sntp(sd_dhcp6_lease *lease, uint8_t *optval, size_t optlen) {
+        int r;
+
+        assert_return(lease, -EINVAL);
+        assert_return(optval, -EINVAL);
+
+        if (!optlen)
+                return 0;
+
+        if (lease->ntp || lease->ntp_fqdn) {
+                log_dhcp6_client(client, "NTP information already provided");
+
+                return 0;
+        }
+
+        log_dhcp6_client(client, "Using deprecated SNTP information");
+
+        r = dhcp6_option_parse_ip6addrs(optval, optlen, &lease->ntp,
+                                        lease->ntp_count,
+                                        &lease->ntp_allocated);
+        if (r < 0) {
+                log_dhcp6_client(client, "Invalid SNTP server option: %s",
+                                 strerror(-r));
+
+                return r;
+        }
+
+        lease->ntp_count = r;
+
+        return 0;
+}
+
 int sd_dhcp6_lease_get_ntp_addrs(sd_dhcp6_lease *lease,
                                  struct in6_addr **addrs) {
         assert_return(lease, -EINVAL);
diff --git a/src/libsystemd-network/test-dhcp6-client.c b/src/libsystemd-network/test-dhcp6-client.c
index 7618547..b61fd38 100644
--- a/src/libsystemd-network/test-dhcp6-client.c
+++ b/src/libsystemd-network/test-dhcp6-client.c
@@ -73,7 +73,7 @@ static int test_client_basic(sd_event *e) {
         assert_se(sd_dhcp6_client_set_request_option(client, DHCP6_OPTION_CLIENTID) == -EINVAL);
         assert_se(sd_dhcp6_client_set_request_option(client, DHCP6_OPTION_DNS_SERVERS) == -EEXIST);
         assert_se(sd_dhcp6_client_set_request_option(client, DHCP6_OPTION_NTP_SERVER) == -EEXIST);
-        assert_se(sd_dhcp6_client_set_request_option(client, DHCP6_OPTION_SNTP_SERVERS) == 0);
+        assert_se(sd_dhcp6_client_set_request_option(client, DHCP6_OPTION_SNTP_SERVERS) == -EEXIST);
         assert_se(sd_dhcp6_client_set_request_option(client, DHCP6_OPTION_DOMAIN_LIST) == -EEXIST);
         assert_se(sd_dhcp6_client_set_request_option(client, 10) == -EINVAL);
 
-- 
2.1.4