diff options
Diffstat (limited to 'src')
-rw-r--r-- | src/lib/protocols/dns.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/src/lib/protocols/dns.c b/src/lib/protocols/dns.c index a2330058f..205777024 100644 --- a/src/lib/protocols/dns.c +++ b/src/lib/protocols/dns.c @@ -641,7 +641,8 @@ static int search_valid_dns(struct ndpi_detection_module_struct *ndpi_struct, } else { /* DNS Reply */ - if((dns_header->num_queries > 0) && (dns_header->num_queries <= NDPI_MAX_DNS_REQUESTS) /* Don't assume that num_queries must be zero */ + if(((dns_header->num_queries > 0 && dns_header->num_queries <= NDPI_MAX_DNS_REQUESTS) || /* Don't assume that num_queries must be zero */ + (checkDNSSubprotocol(ntohs(flow->c_port), ntohs(flow->s_port)) == NDPI_PROTOCOL_MDNS && dns_header->num_queries == 0)) && ((((dns_header->num_answers > 0) && (dns_header->num_answers <= NDPI_MAX_DNS_REQUESTS)) || ((dns_header->authority_rrs > 0) && (dns_header->authority_rrs <= NDPI_MAX_DNS_REQUESTS)) || ((dns_header->additional_rrs > 0) && (dns_header->additional_rrs <= NDPI_MAX_DNS_REQUESTS))) @@ -685,6 +686,10 @@ static int search_valid_dns(struct ndpi_detection_module_struct *ndpi_struct, #endif } } + } else { + if(flow->detected_protocol_stack[0] != NDPI_PROTOCOL_UNKNOWN) + ndpi_set_risk(ndpi_struct, flow, NDPI_MALFORMED_PACKET, "Invalid DNS Header"); + return(1 /* invalid */); } } |