dhcpv6: always include IA_NA and IA_PD in Request message if requested

RFC7550 says that if you request both IA_NA and IA_PD and only one
option is offered in the Advertise, then the client must send a Request
message (and not a Solicit) and the message SHOULD still include both
IA_NA and IA_PD options.

Problem: A Request message is correctly sent instead of a Solicit but it
doesn't include both IA_NA and IA_PD options.

Solution: If IA_NA and IA_PD are requested, the Request message always
includes both options.

Signed-off-by: Nicolas BESNARD <[email protected]>
Signed-off-by: Paul Donald <[email protected]>
Link: https://github.com/openwrt/odhcp6c/pull/106
Signed-off-by: Álvaro Fernández Rojas <[email protected]>

diff --git a/src/dhcpv6.c b/src/dhcpv6.c
index 26276d5da9dd36573d58ce0c86728117a0da75f9..03662704c91d34e581e51681daf1484e4505d18c 100644 (file)
--- a/src/dhcpv6.c
+++ b/src/dhcpv6.c
@@ -724,8 +724,10 @@ static void dhcpv6_send(enum dhcpv6_msg type, uint8_t trid[3], uint32_t ecs)
        // Build IA_PDs
        size_t ia_pd_entries = 0, ia_pd_len = 0;
        uint8_t *ia_pd;
+       struct odhcp6c_entry *e = odhcp6c_get_state(STATE_IA_PD, &ia_pd_entries);
+       ia_pd_entries /= sizeof(*e);
 
-       if (type == DHCPV6_MSG_SOLICIT) {
+       if (type == DHCPV6_MSG_SOLICIT || (type == DHCPV6_MSG_REQUEST && ia_pd_entries == 0 && pd_mode != IA_MODE_NONE)) {
                odhcp6c_clear_state(STATE_IA_PD);
                size_t n_prefixes;
                struct odhcp6c_request_prefix *request_prefixes = odhcp6c_get_state(STATE_IA_PD_INIT, &n_prefixes);
@@ -754,9 +756,6 @@ static void dhcpv6_send(enum dhcpv6_msg type, uint8_t trid[3], uint32_t ecs)
                        }
                }
        } else {
-               struct odhcp6c_entry *e = odhcp6c_get_state(STATE_IA_PD, &ia_pd_entries);
-               ia_pd_entries /= sizeof(*e);
-
                // we're too lazy to count our distinct IAIDs,
                // so just allocate maximally needed space
                ia_pd = alloca(ia_pd_entries * (sizeof(struct dhcpv6_ia_prefix) + 10 +
@@ -835,7 +834,7 @@ static void dhcpv6_send(enum dhcpv6_msg type, uint8_t trid[3], uint32_t ecs)
        // Build IA_NAs
        size_t ia_na_entries, ia_na_len = 0;
        void *ia_na = NULL;
-       struct odhcp6c_entry *e = odhcp6c_get_state(STATE_IA_NA, &ia_na_entries);
+       e = odhcp6c_get_state(STATE_IA_NA, &ia_na_entries);
        ia_na_entries /= sizeof(*e);
 
        struct dhcpv6_ia_hdr hdr_ia_na = {
@@ -937,7 +936,7 @@ static void dhcpv6_send(enum dhcpv6_msg type, uint8_t trid[3], uint32_t ecs)
                cnt = IOV_HDR_IA_NA;
 
        // Disable IAs if not used
-       if (type != DHCPV6_MSG_SOLICIT && ia_na_len == 0)
+       if (type != DHCPV6_MSG_SOLICIT && type != DHCPV6_MSG_REQUEST && ia_na_len == 0)
                iov[IOV_HDR_IA_NA].iov_len = 0;
 
        if (na_mode == IA_MODE_NONE)
@@ -1386,9 +1385,6 @@ static int dhcpv6_handle_reply(enum dhcpv6_msg orig, _unused const int rc,
                                                dhcpv6_handle_ia_status_code(orig, ia_hdr,
                                                        code, mdata, mlen, handled_status_codes, &ret);
 
-                                               if (ret > 0)
-                                                       return ret;
-
                                                break;
                                        }
                                }
@@ -1890,10 +1886,15 @@ static void dhcpv6_handle_ia_status_code(const enum dhcpv6_msg orig,
                        break;
 
                default:
+                       *ret = 0;
                        break;
                }
                break;
 
+       case DHCPV6_NoAddrsAvail:
+       case DHCPV6_NoPrefixAvail:
+               break;
+
        default:
                *ret = 0;
                break;