dhcpv6: send timezone only when client requests

Commit 7956f4271b4e added support for RFC4833 timezones but didn't check
if clients had actually requested them.

Fixes: 7956f4271b4e ("dhcpv6: RFC4833 timezones")
Signed-off-by: Paul Donald <[email protected]>
Link: https://github.com/openwrt/odhcpd/pull/289
Signed-off-by: Álvaro Fernández Rojas <[email protected]>

diff --git a/src/dhcpv6.c b/src/dhcpv6.c
index 000370f0fb8f74a6fa08eae28ccd56c26693589e..ef84687446d2c9e03531c9d8f1ab055dd6f8f026 100644 (file)
--- a/src/dhcpv6.c
+++ b/src/dhcpv6.c
@@ -435,6 +435,7 @@ static void handle_client_request(void *addr, void *data, size_t len,
        } dhcpv6_sntp;
 
        /* RFC 4833 - Timezones */
+       bool posix_want = false;
        uint8_t *posix_ptr = sys_conf.posix_tz;
        uint16_t posix_len = sys_conf.posix_tz_len;
        /* RFC 4833 - OPTION_NEW_POSIX_TIMEZONE (41)
@@ -446,6 +447,7 @@ static void handle_client_request(void *addr, void *data, size_t len,
                uint16_t len;
        } posix_tz;
 
+       bool tzdb_want = false;
        uint8_t *tzdb_ptr = sys_conf.tzdb_tz;
        uint16_t tzdb_len = sys_conf.tzdb_tz_len;
        /* RFC 4833 - OPTION_NEW_TZDB_TIMEZONE (42)
@@ -510,11 +512,13 @@ static void handle_client_request(void *addr, void *data, size_t len,
                        break;
 
                case DHCPV6_OPT_NEW_POSIX_TIMEZONE:
+                       posix_want = true;
                        posix_tz.type = htons(DHCPV6_OPT_NEW_POSIX_TIMEZONE);
                        posix_tz.len  = htons(posix_len);
                        break;
 
                case DHCPV6_OPT_NEW_TZDB_TIMEZONE:
+                       tzdb_want = true;
                        tzdb_tz.type = htons(DHCPV6_OPT_NEW_TZDB_TIMEZONE);
                        tzdb_tz.len  = htons(tzdb_len);
                        break;
@@ -633,10 +637,10 @@ static void handle_client_request(void *addr, void *data, size_t len,
                [IOV_NTP_ADDR] = {ntp_ptr, (ntp_cnt) ? ntp_len : 0},
                [IOV_SNTP] = {&dhcpv6_sntp, (sntp_cnt) ? sizeof(dhcpv6_sntp) : 0},
                [IOV_SNTP_ADDR] = {sntp_addr_ptr, sntp_cnt * sizeof(*sntp_addr_ptr)},
-               [IOV_POSIX_TZ] = {&posix_tz, (posix_len) ? sizeof(posix_tz) : 0},
-               [IOV_POSIX_TZ_STR] = {posix_ptr, (posix_len) ? posix_len : 0 },
-               [IOV_TZDB_TZ] = {&tzdb_tz, (tzdb_len) ? sizeof(tzdb_tz) : 0},
-               [IOV_TZDB_TZ_STR] = {tzdb_ptr, (tzdb_len) ? tzdb_len : 0 },
+               [IOV_POSIX_TZ] = {&posix_tz, (posix_want) ? sizeof(posix_tz) : 0},
+               [IOV_POSIX_TZ_STR] = {posix_ptr, (posix_want) ? posix_len : 0 },
+               [IOV_TZDB_TZ] = {&tzdb_tz, (tzdb_want) ? sizeof(tzdb_tz) : 0},
+               [IOV_TZDB_TZ_STR] = {tzdb_ptr, (tzdb_want) ? tzdb_len : 0 },
                [IOV_DNR] = {dnrs, dnrs_len},
                [IOV_RELAY_MSG] = {NULL, 0},
                [IOV_DHCPV4O6_SERVER] = {&dhcpv4o6_server, 0},