diff options
Diffstat (limited to 'src/rfc1035.c')
| -rw-r--r-- | src/rfc1035.c | 34 |
1 files changed, 18 insertions, 16 deletions
diff --git a/src/rfc1035.c b/src/rfc1035.c index d6d3b49..5c0df56 100644 --- a/src/rfc1035.c +++ b/src/rfc1035.c @@ -538,7 +538,9 @@ static int print_txt(struct dns_header *header, const size_t qlen, char *name, /* Note that the following code can create CNAME chains that don't point to a real record, either because of lack of memory, or lack of SOA records. These are treated by the cache code as expired and cleaned out that way. - Return 1 if we reject an address because it look like part of dns-rebinding attack. */ + Return 1 if we reject an address because it look like part of dns-rebinding attack. + Return 2 if the packet is malformed. +*/ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t now, struct ipsets *ipsets, struct ipsets *nftsets, int is_sign, int check_rebind, int no_cache_dnssec, int secure, int *doctored) @@ -589,7 +591,7 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t namep = p = (unsigned char *)(header+1); if (ntohs(header->qdcount) != 1 || !extract_name(header, qlen, &p, name, 1, 4)) - return 0; /* bad packet */ + return 2; /* bad packet */ GETSHORT(qtype, p); GETSHORT(qclass, p); @@ -607,13 +609,13 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t { cname_loop: if (!(p1 = skip_questions(header, qlen))) - return 0; + return 2; for (j = 0; j < ntohs(header->ancount); j++) { int secflag = 0; if (!(res = extract_name(header, qlen, &p1, name, 0, 10))) - return 0; /* bad packet */ + return 2; /* bad packet */ GETSHORT(aqtype, p1); GETSHORT(aqclass, p1); @@ -651,7 +653,7 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t log_query(secflag | F_CNAME | F_FORWARD | F_UPSTREAM, name, NULL, NULL, 0); if (!extract_name(header, qlen, &p1, name, 1, 0)) - return 0; + return 2; if (aqtype == T_CNAME) { @@ -677,7 +679,7 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t p1 = endrr; if (!CHECK_LEN(header, p1, qlen, 0)) - return 0; /* bad packet */ + return 2; /* bad packet */ } } @@ -722,14 +724,14 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t cname_loop1: if (!(p1 = skip_questions(header, qlen))) - return 0; + return 2; for (j = 0; j < ntohs(header->ancount); j++) { int secflag = 0; if (!(res = extract_name(header, qlen, &p1, name, 0, 10))) - return 0; /* bad packet */ + return 2; /* bad packet */ GETSHORT(aqtype, p1); GETSHORT(aqclass, p1); @@ -747,7 +749,7 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t { p1 = endrr; if (!CHECK_LEN(header, p1, qlen, 0)) - return 0; /* bad packet */ + return 2; /* bad packet */ continue; } @@ -790,7 +792,7 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t namep = p1; if (!extract_name(header, qlen, &p1, name, 1, 0)) - return 0; + return 2; if (qtype != T_CNAME) goto cname_loop1; @@ -813,25 +815,25 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t unsigned char *tmp = namep; if (!CHECK_LEN(header, p1, qlen, 6)) - return 0; /* bad packet */ + return 2; /* bad packet */ GETSHORT(addr.srv.priority, p1); GETSHORT(addr.srv.weight, p1); GETSHORT(addr.srv.srvport, p1); if (!extract_name(header, qlen, &p1, name, 1, 0)) - return 0; + return 2; addr.srv.targetlen = strlen(name) + 1; /* include terminating zero */ if (!(addr.srv.target = blockdata_alloc(name, addr.srv.targetlen))) return 0; /* we overwrote the original name, so get it back here. */ if (!extract_name(header, qlen, &tmp, name, 1, 0)) - return 0; + return 2; } else if (flags & (F_IPV4 | F_IPV6)) { /* copy address into aligned storage */ if (!CHECK_LEN(header, p1, qlen, addrlen)) - return 0; /* bad packet */ + return 2; /* bad packet */ memcpy(&addr, p1, addrlen); /* check for returned address in private space */ @@ -875,7 +877,7 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t if (aqtype == T_TXT) { if (!print_txt(header, qlen, name, p1, ardlen, secflag)) - return 0; + return 2; } else log_query(flags | F_FORWARD | secflag | F_UPSTREAM, name, &addr, NULL, aqtype); @@ -883,7 +885,7 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t p1 = endrr; if (!CHECK_LEN(header, p1, qlen, 0)) - return 0; /* bad packet */ + return 2; /* bad packet */ } if (!found && (qtype != T_ANY || (flags & F_NXDOMAIN))) |