diff options
Diffstat (limited to 'external/unbound/util/data/msgreply.c')
| -rw-r--r-- | external/unbound/util/data/msgreply.c | 29 |
1 files changed, 26 insertions, 3 deletions
diff --git a/external/unbound/util/data/msgreply.c b/external/unbound/util/data/msgreply.c index dc27be905..b1d3df639 100644 --- a/external/unbound/util/data/msgreply.c +++ b/external/unbound/util/data/msgreply.c @@ -57,6 +57,8 @@ time_t MAX_TTL = 3600 * 24 * 10; /* ten days */ /** MIN TTL default for messages and rrsets */ time_t MIN_TTL = 0; +/** MAX Negative TTL, for SOA records in authority section */ +time_t MAX_NEG_TTL = 3600; /* one hour */ /** allocate qinfo, return 0 on error */ static int @@ -153,10 +155,23 @@ repinfo_alloc_rrset_keys(struct reply_info* rep, struct alloc_cache* alloc, return 1; } +/** find the minimumttl in the rdata of SOA record */ +static time_t +soa_find_minttl(struct rr_parse* rr) +{ + uint16_t rlen = sldns_read_uint16(rr->ttl_data+4); + if(rlen < 20) + return 0; /* rdata too small for SOA (dname, dname, 5*32bit) */ + /* minimum TTL is the last 32bit value in the rdata of the record */ + /* at position ttl_data + 4(ttl) + 2(rdatalen) + rdatalen - 4(timeval)*/ + return (time_t)sldns_read_uint32(rr->ttl_data+6+rlen-4); +} + /** do the rdata copy */ static int rdata_copy(sldns_buffer* pkt, struct packed_rrset_data* data, uint8_t* to, - struct rr_parse* rr, time_t* rr_ttl, uint16_t type) + struct rr_parse* rr, time_t* rr_ttl, uint16_t type, + sldns_pkt_section section) { uint16_t pkt_len; const sldns_rr_descriptor* desc; @@ -165,6 +180,14 @@ rdata_copy(sldns_buffer* pkt, struct packed_rrset_data* data, uint8_t* to, /* RFC 2181 Section 8. if msb of ttl is set treat as if zero. */ if(*rr_ttl & 0x80000000U) *rr_ttl = 0; + if(type == LDNS_RR_TYPE_SOA && section == LDNS_SECTION_AUTHORITY) { + /* negative response. see if TTL of SOA record larger than the + * minimum-ttl in the rdata of the SOA record */ + if(*rr_ttl > soa_find_minttl(rr)) + *rr_ttl = soa_find_minttl(rr); + if(*rr_ttl > MAX_NEG_TTL) + *rr_ttl = MAX_NEG_TTL; + } if(*rr_ttl < MIN_TTL) *rr_ttl = MIN_TTL; if(*rr_ttl < data->ttl) @@ -254,7 +277,7 @@ parse_rr_copy(sldns_buffer* pkt, struct rrset_parse* pset, data->rr_data[i] = nextrdata; nextrdata += rr->size; if(!rdata_copy(pkt, data, data->rr_data[i], rr, - &data->rr_ttl[i], pset->type)) + &data->rr_ttl[i], pset->type, pset->section)) return 0; rr = rr->next; } @@ -265,7 +288,7 @@ parse_rr_copy(sldns_buffer* pkt, struct rrset_parse* pset, data->rr_data[i] = nextrdata; nextrdata += rr->size; if(!rdata_copy(pkt, data, data->rr_data[i], rr, - &data->rr_ttl[i], LDNS_RR_TYPE_RRSIG)) + &data->rr_ttl[i], LDNS_RR_TYPE_RRSIG, pset->section)) return 0; rr = rr->next; } |