/* $NetBSD: rpz.c,v 1.9 2015/07/08 17:28:59 christos Exp $ */ /* * Copyright (C) 2011-2015 Internet Systems Consortium, Inc. ("ISC") * * Permission to use, copy, modify, and/or distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR * PERFORMANCE OF THIS SOFTWARE. */ /*! \file */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * Parallel radix trees for databases of response policy IP addresses * * The radix or patricia trees are somewhat specialized to handle response * policy addresses by representing the two sets of IP addresses and name * server IP addresses in a single tree. One set of IP addresses is * for rpz-ip policies or policies triggered by addresses in A or * AAAA records in responses. * The second set is for rpz-nsip policies or policies triggered by addresses * in A or AAAA records for NS records that are authorities for responses. * * Each leaf indicates that an IP address is listed in the IP address or the * name server IP address policy sub-zone (or both) of the corresponding * response policy zone. The policy data such as a CNAME or an A record * is kept in the policy zone. After an IP address has been found in a radix * tree, the node in the policy zone's database is found by converting * the IP address to a domain name in a canonical form. * * * The response policy zone canonical form of an IPv6 address is one of: * prefix.W.W.W.W.W.W.W.W * prefix.WORDS.zz * prefix.WORDS.zz.WORDS * prefix.zz.WORDS * where * prefix is the prefix length of the IPv6 address between 1 and 128 * W is a number between 0 and 65535 * WORDS is one or more numbers W separated with "." * zz corresponds to :: in the standard IPv6 text representation * * The canonical form of IPv4 addresses is: * prefix.B.B.B.B * where * prefix is the prefix length of the address between 1 and 32 * B is a number between 0 and 255 * * Names for IPv4 addresses are distinguished from IPv6 addresses by having * 5 labels all of which are numbers, and a prefix between 1 and 32. */ /* * Use a private definition of IPv6 addresses because s6_addr32 is not * always defined and our IPv6 addresses are in non-standard byte order */ typedef isc_uint32_t dns_rpz_cidr_word_t; #define DNS_RPZ_CIDR_WORD_BITS ((int)sizeof(dns_rpz_cidr_word_t)*8) #define DNS_RPZ_CIDR_KEY_BITS ((int)sizeof(dns_rpz_cidr_key_t)*8) #define DNS_RPZ_CIDR_WORDS (128/DNS_RPZ_CIDR_WORD_BITS) typedef struct { dns_rpz_cidr_word_t w[DNS_RPZ_CIDR_WORDS]; } dns_rpz_cidr_key_t; #define ADDR_V4MAPPED 0xffff #define KEY_IS_IPV4(prefix,ip) ((prefix) >= 96 && (ip)->w[0] == 0 && \ (ip)->w[1] == 0 && (ip)->w[2] == ADDR_V4MAPPED) #define DNS_RPZ_WORD_MASK(b) ((b) == 0 ? (dns_rpz_cidr_word_t)(-1) \ : ((dns_rpz_cidr_word_t)(-1) \ << (DNS_RPZ_CIDR_WORD_BITS - (b)))) /* * Get bit #n from the array of words of an IP address. */ #define DNS_RPZ_IP_BIT(ip, n) (1 & ((ip)->w[(n)/DNS_RPZ_CIDR_WORD_BITS] >> \ (DNS_RPZ_CIDR_WORD_BITS \ - 1 - ((n) % DNS_RPZ_CIDR_WORD_BITS)))) /* * A triplet of arrays of bits flagging the existence of * client-IP, IP, and NSIP policy triggers. */ typedef struct dns_rpz_addr_zbits dns_rpz_addr_zbits_t; struct dns_rpz_addr_zbits { dns_rpz_zbits_t client_ip; dns_rpz_zbits_t ip; dns_rpz_zbits_t nsip; }; /* * A CIDR or radix tree node. */ struct dns_rpz_cidr_node { dns_rpz_cidr_node_t *parent; dns_rpz_cidr_node_t *child[2]; dns_rpz_cidr_key_t ip; dns_rpz_prefix_t prefix; dns_rpz_addr_zbits_t set; dns_rpz_addr_zbits_t sum; }; /* * A pair of arrays of bits flagging the existence of * QNAME and NSDNAME policy triggers. */ typedef struct dns_rpz_nm_zbits dns_rpz_nm_zbits_t; struct dns_rpz_nm_zbits { dns_rpz_zbits_t qname; dns_rpz_zbits_t ns; }; /* * The data in a RBT node has two pairs of bits for policy zones. * One pair is for the corresponding name of the node such as example.com * and the other pair is for a wildcard child such as *.example.com. */ typedef struct dns_rpz_nm_data dns_rpz_nm_data_t; struct dns_rpz_nm_data { dns_rpz_nm_zbits_t set; dns_rpz_nm_zbits_t wild; }; #if 0 /* * Catch a name while debugging. */ static void catch_name(const dns_name_t *src_name, const char *tgt, const char *str) { dns_fixedname_t tgt_namef; dns_name_t *tgt_name; dns_fixedname_init(&tgt_namef); tgt_name = dns_fixedname_name(&tgt_namef); dns_name_fromstring(tgt_name, tgt, DNS_NAME_DOWNCASE, NULL); if (dns_name_equal(src_name, tgt_name)) { isc_log_write(dns_lctx, DNS_LOGCATEGORY_RPZ, DNS_LOGMODULE_RBTDB, DNS_RPZ_ERROR_LEVEL, "rpz hit failed: %s %s", str, tgt); } } #endif const char * dns_rpz_type2str(dns_rpz_type_t type) { switch (type) { case DNS_RPZ_TYPE_CLIENT_IP: return ("CLIENT-IP"); case DNS_RPZ_TYPE_QNAME: return ("QNAME"); case DNS_RPZ_TYPE_IP: return ("IP"); case DNS_RPZ_TYPE_NSIP: return ("NSIP"); case DNS_RPZ_TYPE_NSDNAME: return ("NSDNAME"); case DNS_RPZ_TYPE_BAD: break; } FATAL_ERROR(__FILE__, __LINE__, "impossible rpz type %d", type); return ("impossible"); } dns_rpz_policy_t dns_rpz_str2policy(const char *str) { static struct { const char *str; dns_rpz_policy_t policy; } tbl[] = { {"given", DNS_RPZ_POLICY_GIVEN}, {"disabled", DNS_RPZ_POLICY_DISABLED}, {"passthru", DNS_RPZ_POLICY_PASSTHRU}, {"drop", DNS_RPZ_POLICY_DROP}, {"tcp-only", DNS_RPZ_POLICY_TCP_ONLY}, {"nxdomain", DNS_RPZ_POLICY_NXDOMAIN}, {"nodata", DNS_RPZ_POLICY_NODATA}, {"cname", DNS_RPZ_POLICY_CNAME}, {"no-op", DNS_RPZ_POLICY_PASSTHRU}, /* old passthru */ }; unsigned int n; if (str == NULL) return (DNS_RPZ_POLICY_ERROR); for (n = 0; n < sizeof(tbl)/sizeof(tbl[0]); ++n) { if (!strcasecmp(tbl[n].str, str)) return (tbl[n].policy); } return (DNS_RPZ_POLICY_ERROR); } const char * dns_rpz_policy2str(dns_rpz_policy_t policy) { const char *str; switch (policy) { case DNS_RPZ_POLICY_PASSTHRU: str = "PASSTHRU"; break; case DNS_RPZ_POLICY_DROP: str = "DROP"; break; case DNS_RPZ_POLICY_TCP_ONLY: str = "TCP-ONLY"; break; case DNS_RPZ_POLICY_NXDOMAIN: str = "NXDOMAIN"; break; case DNS_RPZ_POLICY_NODATA: str = "NODATA"; break; case DNS_RPZ_POLICY_RECORD: str = "Local-Data"; break; case DNS_RPZ_POLICY_CNAME: case DNS_RPZ_POLICY_WILDCNAME: str = "CNAME"; break; case DNS_RPZ_POLICY_MISS: str = "MISS"; break; default: str = ""; POST(str); INSIST(0); } return (str); } /* * Return the bit number of the highest set bit in 'zbit'. * (for example, 0x01 returns 0, 0xFF returns 7, etc.) */ static int zbit_to_num(dns_rpz_zbits_t zbit) { dns_rpz_num_t rpz_num; REQUIRE(zbit != 0); rpz_num = 0; #if DNS_RPZ_MAX_ZONES > 32 if ((zbit & 0xffffffff00000000L) != 0) { zbit >>= 32; rpz_num += 32; } #endif if ((zbit & 0xffff0000) != 0) { zbit >>= 16; rpz_num += 16; } if ((zbit & 0xff00) != 0) { zbit >>= 8; rpz_num += 8; } if ((zbit & 0xf0) != 0) { zbit >>= 4; rpz_num += 4; } if ((zbit & 0xc) != 0) { zbit >>= 2; rpz_num += 2; } if ((zbit & 2) != 0) ++rpz_num; return (rpz_num); } /* * Make a set of bit masks given one or more bits and their type. */ static void make_addr_set(dns_rpz_addr_zbits_t *tgt_set, dns_rpz_zbits_t zbits, dns_rpz_type_t type) { switch (type) { case DNS_RPZ_TYPE_CLIENT_IP: tgt_set->client_ip = zbits; tgt_set->ip = 0; tgt_set->nsip = 0; break; case DNS_RPZ_TYPE_IP: tgt_set->client_ip = 0; tgt_set->ip = zbits; tgt_set->nsip = 0; break; case DNS_RPZ_TYPE_NSIP: tgt_set->client_ip = 0; tgt_set->ip = 0; tgt_set->nsip = zbits; break; default: INSIST(0); break; } } static void make_nm_set(dns_rpz_nm_zbits_t *tgt_set, dns_rpz_num_t rpz_num, dns_rpz_type_t type) { switch (type) { case DNS_RPZ_TYPE_QNAME: tgt_set->qname = DNS_RPZ_ZBIT(rpz_num); tgt_set->ns = 0; break; case DNS_RPZ_TYPE_NSDNAME: tgt_set->qname = 0; tgt_set->ns = DNS_RPZ_ZBIT(rpz_num); break; default: INSIST(0); break; } } /* * Mark a node and all of its parents as having client-IP, IP, or NSIP data */ static void set_sum_pair(dns_rpz_cidr_node_t *cnode) { dns_rpz_cidr_node_t *child; dns_rpz_addr_zbits_t sum; do { sum = cnode->set; child = cnode->child[0]; if (child != NULL) { sum.client_ip |= child->sum.client_ip; sum.ip |= child->sum.ip; sum.nsip |= child->sum.nsip; } child = cnode->child[1]; if (child != NULL) { sum.client_ip |= child->sum.client_ip; sum.ip |= child->sum.ip; sum.nsip |= child->sum.nsip; } if (cnode->sum.client_ip == sum.client_ip && cnode->sum.ip == sum.ip && cnode->sum.nsip == sum.nsip) break; cnode->sum = sum; cnode = cnode->parent; } while (cnode != NULL); } /* Caller must hold rpzs->maint_lock */ static void fix_qname_skip_recurse(dns_rpz_zones_t *rpzs) { dns_rpz_zbits_t mask; /* * qname_wait_recurse and qname_skip_recurse are used to * implement the "qname-wait-recurse" config option. * * By default, "qname-wait-recurse" is yes, so no * processing happens without recursion. In this case, * qname_wait_recurse is true, and qname_skip_recurse * (a bit field indicating which policy zones can be * processed without recursion) is set to all 0's by * fix_qname_skip_recurse(). * * When "qname-wait-recurse" is no, qname_skip_recurse may be * set to a non-zero value by fix_qname_skip_recurse(). The mask * has to have bits set for the policy zones for which * processing may continue without recursion, and bits cleared * for the rest. * * (1) The ARM says: * * The "qname-wait-recurse no" option overrides that default * behavior when recursion cannot change a non-error * response. The option does not affect QNAME or client-IP * triggers in policy zones listed after other zones * containing IP, NSIP and NSDNAME triggers, because those may * depend on the A, AAAA, and NS records that would be found * during recursive resolution. * * Let's consider the following: * * zbits_req = (rpzs->have.ipv4 | rpzs->have.ipv6 | * rpzs->have.nsdname | * rpzs->have.nsipv4 | rpzs->have.nsipv6); * * zbits_req now contains bits set for zones which require * recursion. * * But going by the description in the ARM, if the first policy * zone requires recursion, then all zones after that (higher * order bits) have to wait as well. If the Nth zone requires * recursion, then (N+1)th zone onwards all need to wait. * * So mapping this, examples: * * zbits_req = 0b000 mask = 0xffffffff (no zones have to wait for * recursion) * zbits_req = 0b001 mask = 0x00000000 (all zones have to wait) * zbits_req = 0b010 mask = 0x00000001 (the first zone doesn't have to * wait, second zone onwards need * to wait) * zbits_req = 0b011 mask = 0x00000000 (all zones have to wait) * zbits_req = 0b100 mask = 0x00000011 (the 1st and 2nd zones don't * have to wait, third zone * onwards need to wait) * * More generally, we have to count the number of trailing 0 * bits in zbits_req and only these can be processed without * recursion. All the rest need to wait. * * (2) The ARM says that "qname-wait-recurse no" option * overrides the default behavior when recursion cannot change a * non-error response. So, in the order of listing of policy * zones, within the first policy zone where recursion may be * required, we should first allow CLIENT-IP and QNAME policy * records to be attempted without recursion. */ /* * Get a mask covering all policy zones that are not subordinate to * other policy zones containing triggers that require that the * qname be resolved before they can be checked. */ rpzs->have.client_ip = rpzs->have.client_ipv4 | rpzs->have.client_ipv6; rpzs->have.ip = rpzs->have.ipv4 | rpzs->have.ipv6; rpzs->have.nsip = rpzs->have.nsipv4 | rpzs->have.nsipv6; if (rpzs->p.qname_wait_recurse) { mask = 0; } else { dns_rpz_zbits_t zbits_req; dns_rpz_zbits_t zbits_notreq; dns_rpz_zbits_t mask2; dns_rpz_zbits_t req_mask; /* * Get the masks of zones with policies that * do/don't require recursion */ zbits_req = (rpzs->have.ipv4 | rpzs->have.ipv6 | rpzs->have.nsdname | rpzs->have.nsipv4 | rpzs->have.nsipv6); zbits_notreq = (rpzs->have.client_ip | rpzs->have.qname); if (zbits_req == 0) { mask = DNS_RPZ_ALL_ZBITS; goto set; } /* * req_mask is a mask covering used bits in * zbits_req. (For instance, 0b1 => 0b1, 0b101 => 0b111, * 0b11010101 => 0b11111111). */ req_mask = zbits_req; req_mask |= req_mask >> 1; req_mask |= req_mask >> 2; req_mask |= req_mask >> 4; req_mask |= req_mask >> 8; req_mask |= req_mask >> 16; #if DNS_RPZ_MAX_ZONES > 32 req_mask |= req_mask >> 32; #endif /* * There's no point in skipping recursion for a later * zone if it is required in a previous zone. */ if ((zbits_notreq & req_mask) == 0) { mask = 0; goto set; } /* * This bit arithmetic creates a mask of zones in which * it is okay to skip recursion. After the first zone * that has to wait for recursion, all the others have * to wait as well, so we want to create a mask in which * all the trailing zeroes in zbits_req are are 1, and * more significant bits are 0. (For instance, * 0x0700 => 0x00ff, 0x0007 => 0x0000) */ mask = ~(zbits_req | -zbits_req); /* * As mentioned in (2) above, the zone corresponding to * the least significant zero could have its CLIENT-IP * and QNAME policies checked before recursion, if it * has any of those policies. So if it does, we * can set its 0 to 1. * * Locate the least significant 0 bit in the mask (for * instance, 0xff => 0x100)... */ mask2 = (mask << 1) & ~mask; /* * Also set the bit for zone 0, because if it's in * zbits_notreq then it's definitely okay to attempt to * skip recursion for zone 0... */ mask2 |= 1; /* Clear any bits *not* in zbits_notreq... */ mask2 &= zbits_notreq; /* And merge the result into the skip-recursion mask */ mask |= mask2; } set: isc_log_write(dns_lctx, DNS_LOGCATEGORY_RPZ, DNS_LOGMODULE_RBTDB, DNS_RPZ_DEBUG_QUIET, "computed RPZ qname_skip_recurse mask=0x%llx", (isc_uint64_t) mask); rpzs->have.qname_skip_recurse = mask; } static void adj_trigger_cnt(dns_rpz_zones_t *rpzs, dns_rpz_num_t rpz_num, dns_rpz_type_t rpz_type, const dns_rpz_cidr_key_t *tgt_ip, dns_rpz_prefix_t tgt_prefix, isc_boolean_t inc) { dns_rpz_trigger_counter_t *cnt; dns_rpz_zbits_t *have; switch (rpz_type) { case DNS_RPZ_TYPE_CLIENT_IP: REQUIRE(tgt_ip != NULL); if (KEY_IS_IPV4(tgt_prefix, tgt_ip)) { cnt = &rpzs->triggers[rpz_num].client_ipv4; have = &rpzs->have.client_ipv4; } else { cnt = &rpzs->triggers[rpz_num].client_ipv6; have = &rpzs->have.client_ipv6; } break; case DNS_RPZ_TYPE_QNAME: cnt = &rpzs->triggers[rpz_num].qname; have = &rpzs->have.qname; break; case DNS_RPZ_TYPE_IP: REQUIRE(tgt_ip != NULL); if (KEY_IS_IPV4(tgt_prefix, tgt_ip)) { cnt = &rpzs->triggers[rpz_num].ipv4; have = &rpzs->have.ipv4; } else { cnt = &rpzs->triggers[rpz_num].ipv6; have = &rpzs->have.ipv6; } break; case DNS_RPZ_TYPE_NSDNAME: cnt = &rpzs->triggers[rpz_num].nsdname; have = &rpzs->have.nsdname; break; case DNS_RPZ_TYPE_NSIP: REQUIRE(tgt_ip != NULL); if (KEY_IS_IPV4(tgt_prefix, tgt_ip)) { cnt = &rpzs->triggers[rpz_num].nsipv4; have = &rpzs->have.nsipv4; } else { cnt = &rpzs->triggers[rpz_num].nsipv6; have = &rpzs->have.nsipv6; } break; default: INSIST(0); } if (inc) { if (++*cnt == 1) { *have |= DNS_RPZ_ZBIT(rpz_num); fix_qname_skip_recurse(rpzs); } } else { REQUIRE(*cnt != 0); if (--*cnt == 0) { *have &= ~DNS_RPZ_ZBIT(rpz_num); fix_qname_skip_recurse(rpzs); } } } static dns_rpz_cidr_node_t * new_node(dns_rpz_zones_t *rpzs, const dns_rpz_cidr_key_t *ip, dns_rpz_prefix_t prefix, const dns_rpz_cidr_node_t *child) { dns_rpz_cidr_node_t *new; int i, words, wlen; new = isc_mem_get(rpzs->mctx, sizeof(*new)); if (new == NULL) return (NULL); memset(new, 0, sizeof(*new)); if (child != NULL) new->sum = child->sum; new->prefix = prefix; words = prefix / DNS_RPZ_CIDR_WORD_BITS; wlen = prefix % DNS_RPZ_CIDR_WORD_BITS; i = 0; while (i < words) { new->ip.w[i] = ip->w[i]; ++i; } if (wlen != 0) { new->ip.w[i] = ip->w[i] & DNS_RPZ_WORD_MASK(wlen); ++i; } while (i < DNS_RPZ_CIDR_WORDS) new->ip.w[i++] = 0; return (new); } static void badname(int level, dns_name_t *name, const char *str1, const char *str2) { char namebuf[DNS_NAME_FORMATSIZE]; /* * bin/tests/system/rpz/tests.sh looks for "invalid rpz". */ if (level < DNS_RPZ_DEBUG_QUIET && isc_log_wouldlog(dns_lctx, level)) { dns_name_format(name, namebuf, sizeof(namebuf)); isc_log_write(dns_lctx, DNS_LOGCATEGORY_RPZ, DNS_LOGMODULE_RBTDB, level, "invalid rpz IP address \"%s\"%s%s", namebuf, str1, str2); } } /* * Convert an IP address from radix tree binary (host byte order) to * to its canonical response policy domain name without the origin of the * policy zone. */ static isc_result_t ip2name(const dns_rpz_cidr_key_t *tgt_ip, dns_rpz_prefix_t tgt_prefix, dns_name_t *base_name, dns_name_t *ip_name) { #ifndef INET6_ADDRSTRLEN #define INET6_ADDRSTRLEN 46 #endif int w[DNS_RPZ_CIDR_WORDS*2]; char str[1+8+1+INET6_ADDRSTRLEN+1]; isc_buffer_t buffer; isc_result_t result; isc_boolean_t zeros; int i, n, len; if (KEY_IS_IPV4(tgt_prefix, tgt_ip)) { len = snprintf(str, sizeof(str), "%d.%d.%d.%d.%d", tgt_prefix - 96, tgt_ip->w[3] & 0xff, (tgt_ip->w[3]>>8) & 0xff, (tgt_ip->w[3]>>16) & 0xff, (tgt_ip->w[3]>>24) & 0xff); if (len < 0 || len > (int)sizeof(str)) return (ISC_R_FAILURE); } else { for (i = 0; i < DNS_RPZ_CIDR_WORDS; i++) { w[i*2+1] = ((tgt_ip->w[DNS_RPZ_CIDR_WORDS-1-i] >> 16) & 0xffff); w[i*2] = tgt_ip->w[DNS_RPZ_CIDR_WORDS-1-i] & 0xffff; } zeros = ISC_FALSE; len = snprintf(str, sizeof(str), "%d", tgt_prefix); if (len == -1) return (ISC_R_FAILURE); i = 0; while (i < DNS_RPZ_CIDR_WORDS * 2) { if (w[i] != 0 || zeros || i >= DNS_RPZ_CIDR_WORDS * 2 - 1 || w[i+1] != 0) { INSIST((size_t)len <= sizeof(str)); n = snprintf(&str[len], sizeof(str) - len, ".%x", w[i++]); if (n < 0) return (ISC_R_FAILURE); len += n; } else { zeros = ISC_TRUE; INSIST((size_t)len <= sizeof(str)); n = snprintf(&str[len], sizeof(str) - len, ".zz"); if (n < 0) return (ISC_R_FAILURE); len += n; i += 2; while (i < DNS_RPZ_CIDR_WORDS * 2 && w[i] == 0) ++i; } if (len >= (int)sizeof(str)) return (ISC_R_FAILURE); } } isc_buffer_init(&buffer, str, sizeof(str)); isc_buffer_add(&buffer, len); result = dns_name_fromtext(ip_name, &buffer, base_name, 0, NULL); return (result); } /* * Determine the type a of a name in a response policy zone. */ static dns_rpz_type_t type_from_name(dns_rpz_zone_t *rpz, dns_name_t *name) { if (dns_name_issubdomain(name, &rpz->ip)) return (DNS_RPZ_TYPE_IP); if (dns_name_issubdomain(name, &rpz->client_ip)) return (DNS_RPZ_TYPE_CLIENT_IP); #ifdef ENABLE_RPZ_NSIP if (dns_name_issubdomain(name, &rpz->nsip)) return (DNS_RPZ_TYPE_NSIP); #endif #ifdef ENABLE_RPZ_NSDNAME if (dns_name_issubdomain(name, &rpz->nsdname)) return (DNS_RPZ_TYPE_NSDNAME); #endif return (DNS_RPZ_TYPE_QNAME); } /* * Convert an IP address from canonical response policy domain name form * to radix tree binary (host byte order) for adding or deleting IP or NSIP * data. */ static isc_result_t name2ipkey(int log_level, const dns_rpz_zones_t *rpzs, dns_rpz_num_t rpz_num, dns_rpz_type_t rpz_type, dns_name_t *src_name, dns_rpz_cidr_key_t *tgt_ip, dns_rpz_prefix_t *tgt_prefix, dns_rpz_addr_zbits_t *new_set) { dns_rpz_zone_t *rpz; char ip_str[DNS_NAME_FORMATSIZE]; dns_offsets_t ip_name_offsets; dns_fixedname_t ip_name2f; dns_name_t ip_name, *ip_name2; const char *prefix_str, *cp, *end; char *cp2; int ip_labels; dns_rpz_prefix_t prefix; unsigned long prefix_num, l; isc_result_t result; int i; REQUIRE(rpzs != NULL && rpz_num < rpzs->p.num_zones); rpz = rpzs->zones[rpz_num]; REQUIRE(rpz != NULL); make_addr_set(new_set, DNS_RPZ_ZBIT(rpz_num), rpz_type); ip_labels = dns_name_countlabels(src_name); if (rpz_type == DNS_RPZ_TYPE_QNAME) ip_labels -= dns_name_countlabels(&rpz->origin); else ip_labels -= dns_name_countlabels(&rpz->nsdname); if (ip_labels < 2) { badname(log_level, src_name, "; too short", ""); return (ISC_R_FAILURE); } dns_name_init(&ip_name, ip_name_offsets); dns_name_getlabelsequence(src_name, 0, ip_labels, &ip_name); /* * Get text for the IP address */ dns_name_format(&ip_name, ip_str, sizeof(ip_str)); end = &ip_str[strlen(ip_str)+1]; prefix_str = ip_str; prefix_num = strtoul(prefix_str, &cp2, 10); if (*cp2 != '.') { badname(log_level, src_name, "; invalid leading prefix length", ""); return (ISC_R_FAILURE); } *cp2 = '\0'; if (prefix_num < 1U || prefix_num > 128U) { badname(log_level, src_name, "; invalid prefix length of ", prefix_str); return (ISC_R_FAILURE); } cp = cp2+1; if (--ip_labels == 4 && !strchr(cp, 'z')) { /* * Convert an IPv4 address * from the form "prefix.z.y.x.w" */ if (prefix_num > 32U) { badname(log_level, src_name, "; invalid IPv4 prefix length of ", prefix_str); return (ISC_R_FAILURE); } prefix_num += 96; *tgt_prefix = (dns_rpz_prefix_t)prefix_num; tgt_ip->w[0] = 0; tgt_ip->w[1] = 0; tgt_ip->w[2] = ADDR_V4MAPPED; tgt_ip->w[3] = 0; for (i = 0; i < 32; i += 8) { l = strtoul(cp, &cp2, 10); if (l > 255U || (*cp2 != '.' && *cp2 != '\0')) { if (*cp2 == '.') *cp2 = '\0'; badname(log_level, src_name, "; invalid IPv4 octet ", cp); return (ISC_R_FAILURE); } tgt_ip->w[3] |= l << i; cp = cp2 + 1; } } else { /* * Convert a text IPv6 address. */ *tgt_prefix = (dns_rpz_prefix_t)prefix_num; for (i = 0; ip_labels > 0 && i < DNS_RPZ_CIDR_WORDS * 2; ip_labels--) { if (cp[0] == 'z' && cp[1] == 'z' && (cp[2] == '.' || cp[2] == '\0') && i <= 6) { do { if ((i & 1) == 0) tgt_ip->w[3-i/2] = 0; ++i; } while (ip_labels + i <= 8); cp += 3; } else { l = strtoul(cp, &cp2, 16); if (l > 0xffffu || (*cp2 != '.' && *cp2 != '\0')) { if (*cp2 == '.') *cp2 = '\0'; badname(log_level, src_name, "; invalid IPv6 word ", cp); return (ISC_R_FAILURE); } if ((i & 1) == 0) tgt_ip->w[3-i/2] = l; else tgt_ip->w[3-i/2] |= l << 16; i++; cp = cp2 + 1; } } } if (cp != end) { badname(log_level, src_name, "", ""); return (ISC_R_FAILURE); } /* * Check for 1s after the prefix length. */ prefix = (dns_rpz_prefix_t)prefix_num; while (prefix < DNS_RPZ_CIDR_KEY_BITS) { dns_rpz_cidr_word_t aword; i = prefix % DNS_RPZ_CIDR_WORD_BITS; aword = tgt_ip->w[prefix / DNS_RPZ_CIDR_WORD_BITS]; if ((aword & ~DNS_RPZ_WORD_MASK(i)) != 0) { badname(log_level, src_name, "; too small prefix length of ", prefix_str); return (ISC_R_FAILURE); } prefix -= i; prefix += DNS_RPZ_CIDR_WORD_BITS; } /* * XXXMUKS: Should the following check be enabled in a * production build? It can be expensive for large IP zones * from 3rd parties. */ /* * Convert the address back to a canonical domain name * to ensure that the original name is in canonical form. */ dns_fixedname_init(&ip_name2f); ip_name2 = dns_fixedname_name(&ip_name2f); result = ip2name(tgt_ip, (dns_rpz_prefix_t)prefix_num, NULL, ip_name2); if (result != ISC_R_SUCCESS || !dns_name_equal(&ip_name, ip_name2)) { badname(log_level, src_name, "; not canonical", ""); return (ISC_R_FAILURE); } return (ISC_R_SUCCESS); } /* * Get trigger name and data bits for adding or deleting summary NSDNAME * or QNAME data. */ static void name2data(dns_rpz_zones_t *rpzs, dns_rpz_num_t rpz_num, dns_rpz_type_t rpz_type, const dns_name_t *src_name, dns_name_t *trig_name, dns_rpz_nm_data_t *new_data) { dns_rpz_zone_t *rpz; dns_offsets_t tmp_name_offsets; dns_name_t tmp_name; unsigned int prefix_len, n; REQUIRE(rpzs != NULL && rpz_num < rpzs->p.num_zones); rpz = rpzs->zones[rpz_num]; REQUIRE(rpz != NULL); /* * Handle wildcards by putting only the parent into the * summary RBT. The summary database only causes a check of the * real policy zone where wildcards will be handled. */ if (dns_name_iswildcard(src_name)) { prefix_len = 1; memset(&new_data->set, 0, sizeof(new_data->set)); make_nm_set(&new_data->wild, rpz_num, rpz_type); } else { prefix_len = 0; make_nm_set(&new_data->set, rpz_num, rpz_type); memset(&new_data->wild, 0, sizeof(new_data->wild)); } dns_name_init(&tmp_name, tmp_name_offsets); n = dns_name_countlabels(src_name); n -= prefix_len; if (rpz_type == DNS_RPZ_TYPE_QNAME) n -= dns_name_countlabels(&rpz->origin); else n -= dns_name_countlabels(&rpz->nsdname); dns_name_getlabelsequence(src_name, prefix_len, n, &tmp_name); (void)dns_name_concatenate(&tmp_name, dns_rootname, trig_name, NULL); } /* * Find the first differing bit in a key (IP address) word. */ static inline int ffs_keybit(dns_rpz_cidr_word_t w) { int bit; bit = DNS_RPZ_CIDR_WORD_BITS-1; if ((w & 0xffff0000) != 0) { w >>= 16; bit -= 16; } if ((w & 0xff00) != 0) { w >>= 8; bit -= 8; } if ((w & 0xf0) != 0) { w >>= 4; bit -= 4; } if ((w & 0xc) != 0) { w >>= 2; bit -= 2; } if ((w & 2) != 0) --bit; return (bit); } /* * Find the first differing bit in two keys (IP addresses). */ static int diff_keys(const dns_rpz_cidr_key_t *key1, dns_rpz_prefix_t prefix1, const dns_rpz_cidr_key_t *key2, dns_rpz_prefix_t prefix2) { dns_rpz_cidr_word_t delta; dns_rpz_prefix_t maxbit, bit; int i; bit = 0; maxbit = ISC_MIN(prefix1, prefix2); /* * find the first differing words */ for (i = 0; bit < maxbit; i++, bit += DNS_RPZ_CIDR_WORD_BITS) { delta = key1->w[i] ^ key2->w[i]; if (delta != 0) { bit += ffs_keybit(delta); break; } } return (ISC_MIN(bit, maxbit)); } /* * Given a hit while searching the radix trees, * clear all bits for higher numbered zones. */ static inline dns_rpz_zbits_t trim_zbits(dns_rpz_zbits_t zbits, dns_rpz_zbits_t found) { dns_rpz_zbits_t x; /* * Isolate the first or smallest numbered hit bit. * Make a mask of that bit and all smaller numbered bits. */ x = zbits & found; x &= (~x + 1); x = (x << 1) - 1; return (zbits &= x); } /* * Search a radix tree for an IP address for ordinary lookup * or for a CIDR block adding or deleting an entry * * Return ISC_R_SUCCESS, DNS_R_PARTIALMATCH, ISC_R_NOTFOUND, * and *found=longest match node * or with create==ISC_TRUE, ISC_R_EXISTS or ISC_R_NOMEMORY */ static isc_result_t search(dns_rpz_zones_t *rpzs, const dns_rpz_cidr_key_t *tgt_ip, dns_rpz_prefix_t tgt_prefix, const dns_rpz_addr_zbits_t *tgt_set, isc_boolean_t create, dns_rpz_cidr_node_t **found) { dns_rpz_cidr_node_t *cur, *parent, *child, *new_parent, *sibling; dns_rpz_addr_zbits_t set; int cur_num, child_num; dns_rpz_prefix_t dbit; isc_result_t find_result; set = *tgt_set; find_result = ISC_R_NOTFOUND; *found = NULL; cur = rpzs->cidr; parent = NULL; cur_num = 0; for (;;) { if (cur == NULL) { /* * No child so we cannot go down. * Quit with whatever we already found * or add the target as a child of the current parent. */ if (!create) return (find_result); child = new_node(rpzs, tgt_ip, tgt_prefix, NULL); if (child == NULL) return (ISC_R_NOMEMORY); if (parent == NULL) rpzs->cidr = child; else parent->child[cur_num] = child; child->parent = parent; child->set.client_ip |= tgt_set->client_ip; child->set.ip |= tgt_set->ip; child->set.nsip |= tgt_set->nsip; set_sum_pair(child); *found = child; return (ISC_R_SUCCESS); } if ((cur->sum.client_ip & set.client_ip) == 0 && (cur->sum.ip & set.ip) == 0 && (cur->sum.nsip & set.nsip) == 0) { /* * This node has no relevant data * and is in none of the target trees. * Pretend it does not exist if we are not adding. * * If we are adding, continue down to eventually add * a node and mark/put this node in the correct tree. */ if (!create) return (find_result); } dbit = diff_keys(tgt_ip, tgt_prefix, &cur->ip, cur->prefix); /* * dbit <= tgt_prefix and dbit <= cur->prefix always. * We are finished searching if we matched all of the target. */ if (dbit == tgt_prefix) { if (tgt_prefix == cur->prefix) { /* * The node's key matches the target exactly. */ if ((cur->set.client_ip & set.client_ip) != 0 || (cur->set.ip & set.ip) != 0 || (cur->set.nsip & set.nsip) != 0) { /* * It is the answer if it has data. */ *found = cur; if (create) { find_result = ISC_R_EXISTS; } else { find_result = ISC_R_SUCCESS; } } else if (create) { /* * The node lacked relevant data, * but will have it now. */ cur->set.client_ip |= tgt_set->client_ip; cur->set.ip |= tgt_set->ip; cur->set.nsip |= tgt_set->nsip; set_sum_pair(cur); *found = cur; find_result = ISC_R_SUCCESS; } return (find_result); } /* * We know tgt_prefix < cur->prefix which means that * the target is shorter than the current node. * Add the target as the current node's parent. */ if (!create) return (find_result); new_parent = new_node(rpzs, tgt_ip, tgt_prefix, cur); if (new_parent == NULL) return (ISC_R_NOMEMORY); new_parent->parent = parent; if (parent == NULL) rpzs->cidr = new_parent; else parent->child[cur_num] = new_parent; child_num = DNS_RPZ_IP_BIT(&cur->ip, tgt_prefix+1); new_parent->child[child_num] = cur; cur->parent = new_parent; new_parent->set = *tgt_set; set_sum_pair(new_parent); *found = new_parent; return (ISC_R_SUCCESS); } if (dbit == cur->prefix) { if ((cur->set.client_ip & set.client_ip) != 0 || (cur->set.ip & set.ip) != 0 || (cur->set.nsip & set.nsip) != 0) { /* * We have a partial match between of all of the * current node but only part of the target. * Continue searching for other hits in the * same or lower numbered trees. */ find_result = DNS_R_PARTIALMATCH; *found = cur; set.client_ip = trim_zbits(set.client_ip, cur->set.client_ip); set.ip = trim_zbits(set.ip, cur->set.ip); set.nsip = trim_zbits(set.nsip, cur->set.nsip); } parent = cur; cur_num = DNS_RPZ_IP_BIT(tgt_ip, dbit); cur = cur->child[cur_num]; continue; } /* * dbit < tgt_prefix and dbit < cur->prefix, * so we failed to match both the target and the current node. * Insert a fork of a parent above the current node and * add the target as a sibling of the current node */ if (!create) return (find_result); sibling = new_node(rpzs, tgt_ip, tgt_prefix, NULL); if (sibling == NULL) return (ISC_R_NOMEMORY); new_parent = new_node(rpzs, tgt_ip, dbit, cur); if (new_parent == NULL) { isc_mem_put(rpzs->mctx, sibling, sizeof(*sibling)); return (ISC_R_NOMEMORY); } new_parent->parent = parent; if (parent == NULL) rpzs->cidr = new_parent; else parent->child[cur_num] = new_parent; child_num = DNS_RPZ_IP_BIT(tgt_ip, dbit); new_parent->child[child_num] = sibling; new_parent->child[1-child_num] = cur; cur->parent = new_parent; sibling->parent = new_parent; sibling->set = *tgt_set; set_sum_pair(sibling); *found = sibling; return (ISC_R_SUCCESS); } } /* * Add an IP address to the radix tree. */ static isc_result_t add_cidr(dns_rpz_zones_t *rpzs, dns_rpz_num_t rpz_num, dns_rpz_type_t rpz_type, dns_name_t *src_name) { dns_rpz_cidr_key_t tgt_ip; dns_rpz_prefix_t tgt_prefix; dns_rpz_addr_zbits_t set; dns_rpz_cidr_node_t *found; isc_result_t result; result = name2ipkey(DNS_RPZ_ERROR_LEVEL, rpzs, rpz_num, rpz_type, src_name, &tgt_ip, &tgt_prefix, &set); /* * Log complaints about bad owner names but let the zone load. */ if (result != ISC_R_SUCCESS) return (ISC_R_SUCCESS); result = search(rpzs, &tgt_ip, tgt_prefix, &set, ISC_TRUE, &found); if (result != ISC_R_SUCCESS) { char namebuf[DNS_NAME_FORMATSIZE]; /* * Do not worry if the radix tree already exists, * because diff_apply() likes to add nodes before deleting. */ if (result == ISC_R_EXISTS) return (ISC_R_SUCCESS); /* * bin/tests/system/rpz/tests.sh looks for "rpz.*failed". */ dns_name_format(src_name, namebuf, sizeof(namebuf)); isc_log_write(dns_lctx, DNS_LOGCATEGORY_RPZ, DNS_LOGMODULE_RBTDB, DNS_RPZ_ERROR_LEVEL, "rpz add_cidr(%s) failed: %s", namebuf, isc_result_totext(result)); return (result); } adj_trigger_cnt(rpzs, rpz_num, rpz_type, &tgt_ip, tgt_prefix, ISC_TRUE); return (result); } static isc_result_t add_nm(dns_rpz_zones_t *rpzs, dns_name_t *trig_name, const dns_rpz_nm_data_t *new_data) { dns_rbtnode_t *nmnode; dns_rpz_nm_data_t *nm_data; isc_result_t result; nmnode = NULL; result = dns_rbt_addnode(rpzs->rbt, trig_name, &nmnode); switch (result) { case ISC_R_SUCCESS: case ISC_R_EXISTS: nm_data = nmnode->data; if (nm_data == NULL) { nm_data = isc_mem_get(rpzs->mctx, sizeof(*nm_data)); if (nm_data == NULL) return (ISC_R_NOMEMORY); *nm_data = *new_data; nmnode->data = nm_data; return (ISC_R_SUCCESS); } break; default: return (result); } /* * Do not count bits that are already present */ if ((nm_data->set.qname & new_data->set.qname) != 0 || (nm_data->set.ns & new_data->set.ns) != 0 || (nm_data->wild.qname & new_data->wild.qname) != 0 || (nm_data->wild.ns & new_data->wild.ns) != 0) return (ISC_R_EXISTS); nm_data->set.qname |= new_data->set.qname; nm_data->set.ns |= new_data->set.ns; nm_data->wild.qname |= new_data->wild.qname; nm_data->wild.ns |= new_data->wild.ns; return (ISC_R_SUCCESS); } static isc_result_t add_name(dns_rpz_zones_t *rpzs, dns_rpz_num_t rpz_num, dns_rpz_type_t rpz_type, dns_name_t *src_name) { dns_rpz_nm_data_t new_data; dns_fixedname_t trig_namef; dns_name_t *trig_name; isc_result_t result; /* * No need for a summary database of names with only 1 policy zone. */ if (rpzs->p.num_zones <= 1) { adj_trigger_cnt(rpzs, rpz_num, rpz_type, NULL, 0, ISC_TRUE); return (ISC_R_SUCCESS); } dns_fixedname_init(&trig_namef); trig_name = dns_fixedname_name(&trig_namef); name2data(rpzs, rpz_num, rpz_type, src_name, trig_name, &new_data); result = add_nm(rpzs, trig_name, &new_data); /* * Do not worry if the node already exists, * because diff_apply() likes to add nodes before deleting. */ if (result == ISC_R_EXISTS) return (ISC_R_SUCCESS); if (result == ISC_R_SUCCESS) adj_trigger_cnt(rpzs, rpz_num, rpz_type, NULL, 0, ISC_TRUE); return (result); } /* * Callback to free the data for a node in the summary RBT database. */ static void rpz_node_deleter(void *nm_data, void *mctx) { isc_mem_put(mctx, nm_data, sizeof(dns_rpz_nm_data_t)); } /* * Get ready for a new set of policy zones. */ isc_result_t dns_rpz_new_zones(dns_rpz_zones_t **rpzsp, isc_mem_t *mctx) { dns_rpz_zones_t *new; isc_result_t result; REQUIRE(rpzsp != NULL && *rpzsp == NULL); *rpzsp = NULL; new = isc_mem_get(mctx, sizeof(*new)); if (new == NULL) return (ISC_R_NOMEMORY); memset(new, 0, sizeof(*new)); result = isc_rwlock_init(&new->search_lock, 0, 0); if (result != ISC_R_SUCCESS) { isc_mem_put(mctx, new, sizeof(*new)); return (result); } result = isc_mutex_init(&new->maint_lock); if (result != ISC_R_SUCCESS) { isc_rwlock_destroy(&new->search_lock); isc_mem_put(mctx, new, sizeof(*new)); return (result); } result = isc_refcount_init(&new->refs, 1); if (result != ISC_R_SUCCESS) { DESTROYLOCK(&new->maint_lock); isc_rwlock_destroy(&new->search_lock); isc_mem_put(mctx, new, sizeof(*new)); return (result); } result = dns_rbt_create(mctx, rpz_node_deleter, mctx, &new->rbt); if (result != ISC_R_SUCCESS) { isc_refcount_decrement(&new->refs, NULL); isc_refcount_destroy(&new->refs); DESTROYLOCK(&new->maint_lock); isc_rwlock_destroy(&new->search_lock); isc_mem_put(mctx, new, sizeof(*new)); return (result); } isc_mem_attach(mctx, &new->mctx); *rpzsp = new; return (ISC_R_SUCCESS); } /* * Free the radix tree of a response policy database. */ static void cidr_free(dns_rpz_zones_t *rpzs) { dns_rpz_cidr_node_t *cur, *child, *parent; cur = rpzs->cidr; while (cur != NULL) { /* Depth first. */ child = cur->child[0]; if (child != NULL) { cur = child; continue; } child = cur->child[1]; if (child != NULL) { cur = child; continue; } /* Delete this leaf and go up. */ parent = cur->parent; if (parent == NULL) rpzs->cidr = NULL; else parent->child[parent->child[1] == cur] = NULL; isc_mem_put(rpzs->mctx, cur, sizeof(*cur)); cur = parent; } } /* * Discard a response policy zone blob * before discarding the overall rpz structure. */ static void rpz_detach(dns_rpz_zone_t **rpzp, dns_rpz_zones_t *rpzs) { dns_rpz_zone_t *rpz; unsigned int refs; rpz = *rpzp; *rpzp = NULL; isc_refcount_decrement(&rpz->refs, &refs); if (refs != 0) return; isc_refcount_destroy(&rpz->refs); if (dns_name_dynamic(&rpz->origin)) dns_name_free(&rpz->origin, rpzs->mctx); if (dns_name_dynamic(&rpz->client_ip)) dns_name_free(&rpz->client_ip, rpzs->mctx); if (dns_name_dynamic(&rpz->ip)) dns_name_free(&rpz->ip, rpzs->mctx); if (dns_name_dynamic(&rpz->nsdname)) dns_name_free(&rpz->nsdname, rpzs->mctx); if (dns_name_dynamic(&rpz->nsip)) dns_name_free(&rpz->nsip, rpzs->mctx); if (dns_name_dynamic(&rpz->passthru)) dns_name_free(&rpz->passthru, rpzs->mctx); if (dns_name_dynamic(&rpz->drop)) dns_name_free(&rpz->drop, rpzs->mctx); if (dns_name_dynamic(&rpz->tcp_only)) dns_name_free(&rpz->tcp_only, rpzs->mctx); if (dns_name_dynamic(&rpz->cname)) dns_name_free(&rpz->cname, rpzs->mctx); isc_mem_put(rpzs->mctx, rpz, sizeof(*rpz)); } void dns_rpz_attach_rpzs(dns_rpz_zones_t *rpzs, dns_rpz_zones_t **rpzsp) { REQUIRE(rpzsp != NULL && *rpzsp == NULL); isc_refcount_increment(&rpzs->refs, NULL); *rpzsp = rpzs; } /* * Forget a view's policy zones. */ void dns_rpz_detach_rpzs(dns_rpz_zones_t **rpzsp) { dns_rpz_zones_t *rpzs; dns_rpz_zone_t *rpz; dns_rpz_num_t rpz_num; unsigned int refs; REQUIRE(rpzsp != NULL); rpzs = *rpzsp; REQUIRE(rpzs != NULL); *rpzsp = NULL; isc_refcount_decrement(&rpzs->refs, &refs); /* * Forget the last of view's rpz machinery after the last reference. */ if (refs == 0) { for (rpz_num = 0; rpz_num < DNS_RPZ_MAX_ZONES; ++rpz_num) { rpz = rpzs->zones[rpz_num]; rpzs->zones[rpz_num] = NULL; if (rpz != NULL) rpz_detach(&rpz, rpzs); } cidr_free(rpzs); dns_rbt_destroy(&rpzs->rbt); DESTROYLOCK(&rpzs->maint_lock); isc_rwlock_destroy(&rpzs->search_lock); isc_refcount_destroy(&rpzs->refs); isc_mem_putanddetach(&rpzs->mctx, rpzs, sizeof(*rpzs)); } } /* * Create empty summary database to load one zone. * The RBTDB write tree lock must be held. */ isc_result_t dns_rpz_beginload(dns_rpz_zones_t **load_rpzsp, dns_rpz_zones_t *rpzs, dns_rpz_num_t rpz_num) { dns_rpz_zones_t *load_rpzs; dns_rpz_zone_t *rpz; dns_rpz_zbits_t tgt; isc_result_t result; REQUIRE(rpz_num < rpzs->p.num_zones); rpz = rpzs->zones[rpz_num]; REQUIRE(rpz != NULL); /* * When reloading a zone, there are usually records among the summary * data for the zone. Some of those records might be deleted by the * reloaded zone data. To deal with that case: * reload the new zone data into a new blank summary database * if the reload fails, discard the new summary database * if the new zone data is acceptable, copy the records for the * other zones into the new summary CIDR and RBT databases * and replace the old summary databases with the new, and * correct the triggers and have values for the updated * zone. * * At the first attempt to load a zone, there is no summary data * for the zone and so no records that need to be deleted. * This is also the most common case of policy zone loading. * Most policy zone maintenance should be by incremental changes * and so by the addition and deletion of individual records. * Detect that case and load records the first time into the * operational summary database */ tgt = DNS_RPZ_ZBIT(rpz_num); LOCK(&rpzs->maint_lock); RWLOCK(&rpzs->search_lock, isc_rwlocktype_write); if ((rpzs->load_begun & tgt) == 0) { /* * There is no existing version of the target zone. */ rpzs->load_begun |= tgt; dns_rpz_attach_rpzs(rpzs, load_rpzsp); } else { /* * Setup the new RPZ struct with empty summary trees. */ result = dns_rpz_new_zones(load_rpzsp, rpzs->mctx); if (result != ISC_R_SUCCESS) return (result); load_rpzs = *load_rpzsp; /* * Initialize some members so that dns_rpz_add() works. */ load_rpzs->p.num_zones = rpzs->p.num_zones; memset(&load_rpzs->triggers, 0, sizeof(load_rpzs->triggers)); load_rpzs->zones[rpz_num] = rpz; isc_refcount_increment(&rpz->refs, NULL); } RWUNLOCK(&rpzs->search_lock, isc_rwlocktype_write); UNLOCK(&rpzs->maint_lock); return (ISC_R_SUCCESS); } /* * This function updates "have" bits and also the qname_skip_recurse * mask. It must be called when holding a write lock on rpzs->search_lock. */ static void fix_triggers(dns_rpz_zones_t *rpzs, dns_rpz_num_t rpz_num) { dns_rpz_num_t n; dns_rpz_triggers_t old_totals; dns_rpz_zbits_t zbit; char namebuf[DNS_NAME_FORMATSIZE]; /* * rpzs->total_triggers is only used to log a message below. */ memmove(&old_totals, &rpzs->total_triggers, sizeof(old_totals)); memset(&rpzs->total_triggers, 0, sizeof(rpzs->total_triggers)); #define SET_TRIG(n, zbit, type) \ if (rpzs->triggers[n].type == 0) { \ rpzs->have.type &= ~zbit; \ } else { \ rpzs->total_triggers.type += rpzs->triggers[n].type; \ rpzs->have.type |= zbit; \ } for (n = 0; n < rpzs->p.num_zones; ++n) { zbit = DNS_RPZ_ZBIT(n); SET_TRIG(n, zbit, client_ipv4); SET_TRIG(n, zbit, client_ipv6); SET_TRIG(n, zbit, qname); SET_TRIG(n, zbit, ipv4); SET_TRIG(n, zbit, ipv6); SET_TRIG(n, zbit, nsdname); SET_TRIG(n, zbit, nsipv4); SET_TRIG(n, zbit, nsipv6); } #undef SET_TRIG fix_qname_skip_recurse(rpzs); dns_name_format(&rpzs->zones[rpz_num]->origin, namebuf, sizeof(namebuf)); isc_log_write(dns_lctx, DNS_LOGCATEGORY_RPZ, DNS_LOGMODULE_RBTDB, DNS_RPZ_INFO_LEVEL, "(re)loading policy zone '%s' changed from" " %lu to %lu qname, %lu to %lu nsdname," " %lu to %lu IP, %lu to %lu NSIP," " %lu to %lu CLIENTIP entries", namebuf, (unsigned long) old_totals.qname, (unsigned long) rpzs->total_triggers.qname, (unsigned long) old_totals.nsdname, (unsigned long) rpzs->total_triggers.nsdname, (unsigned long) old_totals.ipv4 + old_totals.ipv6, (unsigned long) (rpzs->total_triggers.ipv4 + rpzs->total_triggers.ipv6), (unsigned long) old_totals.nsipv4 + old_totals.nsipv6, (unsigned long) (rpzs->total_triggers.nsipv4 + rpzs->total_triggers.nsipv6), (unsigned long) old_totals.client_ipv4 + old_totals.client_ipv6, (unsigned long) (rpzs->total_triggers.client_ipv4 + rpzs->total_triggers.client_ipv6)); } /* * Finish loading one zone. This function is called during a commit when * a RPZ zone loading is complete. The RBTDB write tree lock must be * held. * * Here, rpzs is a pointer to the view's common rpzs * structure. *load_rpzsp is a rpzs structure that is local to the * RBTDB, which is used during a single zone's load. * * During the zone load, i.e., between dns_rpz_beginload() and * dns_rpz_ready(), only the zone that is being loaded updates * *load_rpzsp. These updates in the summary databases inside load_rpzsp * are made only for the rpz_num (and corresponding bit) of that * zone. Nothing else reads or writes *load_rpzsp. The view's common * rpzs is used during this time for queries. * * When zone loading is complete and we arrive here, the parts of the * summary databases (CIDR and nsdname+qname RBT trees) from the view's * common rpzs struct have to be merged into the summary databases of * *load_rpzsp, as the summary databases of the view's common rpzs * struct may have changed during the time the zone was being loaded. * * The function below carries out the merge. During the merge, it holds * the maint_lock of the view's common rpzs struct so that it is not * updated while the merging is taking place. * * After the merging is carried out, *load_rpzsp contains the most * current state of the rpzs structure, i.e., the summary trees contain * data for the new zone that was just loaded, as well as all other * zones. * * Pointers to the summary databases of *load_rpzsp (CIDR and * nsdname+qname RBT trees) are then swapped into the view's common rpz * struct, so that the query path can continue using it. During the * swap, the search_lock of the view's common rpz struct is acquired so * that queries are paused while this swap occurs. * * The trigger counts for the new zone are also copied into the view's * common rpz struct, and some other summary counts and masks are * updated. */ isc_result_t dns_rpz_ready(dns_rpz_zones_t *rpzs, dns_rpz_zones_t **load_rpzsp, dns_rpz_num_t rpz_num) { dns_rpz_zones_t *load_rpzs; const dns_rpz_cidr_node_t *cnode, *next_cnode, *parent_cnode; dns_rpz_cidr_node_t *found; dns_rpz_zbits_t new_bit; dns_rpz_addr_zbits_t new_ip; dns_rbt_t *rbt; dns_rbtnodechain_t chain; dns_rbtnode_t *nmnode; dns_rpz_nm_data_t *nm_data, new_data; dns_fixedname_t labelf, originf, namef; dns_name_t *label, *origin, *name; isc_result_t result; INSIST(rpzs != NULL); LOCK(&rpzs->maint_lock); load_rpzs = *load_rpzsp; INSIST(load_rpzs != NULL); if (load_rpzs == rpzs) { /* * This is a successful initial zone loading, perhaps * for a new instance of a view. */ RWLOCK(&rpzs->search_lock, isc_rwlocktype_write); fix_triggers(rpzs, rpz_num); RWUNLOCK(&rpzs->search_lock, isc_rwlocktype_write); UNLOCK(&rpzs->maint_lock); dns_rpz_detach_rpzs(load_rpzsp); return (ISC_R_SUCCESS); } LOCK(&load_rpzs->maint_lock); RWLOCK(&load_rpzs->search_lock, isc_rwlocktype_write); /* * Unless there is only one policy zone, copy the other policy zones * from the old policy structure to the new summary databases. */ if (rpzs->p.num_zones > 1) { new_bit = ~DNS_RPZ_ZBIT(rpz_num); /* * Copy to the radix tree. */ for (cnode = rpzs->cidr; cnode != NULL; cnode = next_cnode) { new_ip.ip = cnode->set.ip & new_bit; new_ip.client_ip = cnode->set.client_ip & new_bit; new_ip.nsip = cnode->set.nsip & new_bit; if (new_ip.client_ip != 0 || new_ip.ip != 0 || new_ip.nsip != 0) { result = search(load_rpzs, &cnode->ip, cnode->prefix, &new_ip, ISC_TRUE, &found); if (result == ISC_R_NOMEMORY) goto unlock_and_detach; INSIST(result == ISC_R_SUCCESS); } /* * Do down and to the left as far as possible. */ next_cnode = cnode->child[0]; if (next_cnode != NULL) continue; /* * Go up until we find a branch to the right where * we previously took the branch to the left. */ for (;;) { parent_cnode = cnode->parent; if (parent_cnode == NULL) break; if (parent_cnode->child[0] == cnode) { next_cnode = parent_cnode->child[1]; if (next_cnode != NULL) break; } cnode = parent_cnode; } } /* * Copy to the summary RBT. */ dns_fixedname_init(&namef); name = dns_fixedname_name(&namef); dns_fixedname_init(&labelf); label = dns_fixedname_name(&labelf); dns_fixedname_init(&originf); origin = dns_fixedname_name(&originf); dns_rbtnodechain_init(&chain, NULL); result = dns_rbtnodechain_first(&chain, rpzs->rbt, NULL, NULL); while (result == DNS_R_NEWORIGIN || result == ISC_R_SUCCESS) { result = dns_rbtnodechain_current(&chain, label, origin, &nmnode); INSIST(result == ISC_R_SUCCESS); nm_data = nmnode->data; if (nm_data != NULL) { new_data.set.qname = (nm_data->set.qname & new_bit); new_data.set.ns = nm_data->set.ns & new_bit; new_data.wild.qname = (nm_data->wild.qname & new_bit); new_data.wild.ns = nm_data->wild.ns & new_bit; if (new_data.set.qname != 0 || new_data.set.ns != 0 || new_data.wild.qname != 0 || new_data.wild.ns != 0) { result = dns_name_concatenate(label, origin, name, NULL); INSIST(result == ISC_R_SUCCESS); result = add_nm(load_rpzs, name, &new_data); if (result != ISC_R_SUCCESS) goto unlock_and_detach; } } result = dns_rbtnodechain_next(&chain, NULL, NULL); } if (result != ISC_R_NOMORE && result != ISC_R_NOTFOUND) { isc_log_write(dns_lctx, DNS_LOGCATEGORY_RPZ, DNS_LOGMODULE_RBTDB, DNS_RPZ_ERROR_LEVEL, "dns_rpz_ready(): unexpected %s", isc_result_totext(result)); goto unlock_and_detach; } } /* * Exchange the summary databases. */ RWLOCK(&rpzs->search_lock, isc_rwlocktype_write); rpzs->triggers[rpz_num] = load_rpzs->triggers[rpz_num]; fix_triggers(rpzs, rpz_num); found = rpzs->cidr; rpzs->cidr = load_rpzs->cidr; load_rpzs->cidr = found; rbt = rpzs->rbt; rpzs->rbt = load_rpzs->rbt; load_rpzs->rbt = rbt; RWUNLOCK(&rpzs->search_lock, isc_rwlocktype_write); result = ISC_R_SUCCESS; unlock_and_detach: UNLOCK(&rpzs->maint_lock); RWUNLOCK(&load_rpzs->search_lock, isc_rwlocktype_write); UNLOCK(&load_rpzs->maint_lock); dns_rpz_detach_rpzs(load_rpzsp); return (result); } /* * Add an IP address to the radix tree or a name to the summary database. */ isc_result_t dns_rpz_add(dns_rpz_zones_t *rpzs, dns_rpz_num_t rpz_num, dns_name_t *src_name) { dns_rpz_zone_t *rpz; dns_rpz_type_t rpz_type; isc_result_t result = ISC_R_FAILURE; REQUIRE(rpzs != NULL && rpz_num < rpzs->p.num_zones); rpz = rpzs->zones[rpz_num]; REQUIRE(rpz != NULL); rpz_type = type_from_name(rpz, src_name); LOCK(&rpzs->maint_lock); RWLOCK(&rpzs->search_lock, isc_rwlocktype_write); switch (rpz_type) { case DNS_RPZ_TYPE_QNAME: case DNS_RPZ_TYPE_NSDNAME: result = add_name(rpzs, rpz_num, rpz_type, src_name); break; case DNS_RPZ_TYPE_CLIENT_IP: case DNS_RPZ_TYPE_IP: case DNS_RPZ_TYPE_NSIP: result = add_cidr(rpzs, rpz_num, rpz_type, src_name); break; case DNS_RPZ_TYPE_BAD: break; } RWUNLOCK(&rpzs->search_lock, isc_rwlocktype_write); UNLOCK(&rpzs->maint_lock); return (result); } /* * Remove an IP address from the radix tree. */ static void del_cidr(dns_rpz_zones_t *rpzs, dns_rpz_num_t rpz_num, dns_rpz_type_t rpz_type, dns_name_t *src_name) { isc_result_t result; dns_rpz_cidr_key_t tgt_ip; dns_rpz_prefix_t tgt_prefix; dns_rpz_addr_zbits_t tgt_set; dns_rpz_cidr_node_t *tgt, *parent, *child; /* * Do not worry about invalid rpz IP address names. If we * are here, then something relevant was added and so was * valid. Invalid names here are usually internal RBTDB nodes. */ result = name2ipkey(DNS_RPZ_DEBUG_QUIET, rpzs, rpz_num, rpz_type, src_name, &tgt_ip, &tgt_prefix, &tgt_set); if (result != ISC_R_SUCCESS) return; result = search(rpzs, &tgt_ip, tgt_prefix, &tgt_set, ISC_FALSE, &tgt); if (result != ISC_R_SUCCESS) { INSIST(result == ISC_R_NOTFOUND || result == DNS_R_PARTIALMATCH); /* * Do not worry about missing summary RBT nodes that probably * correspond to RBTDB nodes that were implicit RBT nodes * that were later added for (often empty) wildcards * and then to the RBTDB deferred cleanup list. */ return; } /* * Mark the node and its parents to reflect the deleted IP address. * Do not count bits that are already clear for internal RBTDB nodes. */ tgt_set.client_ip &= tgt->set.client_ip; tgt_set.ip &= tgt->set.ip; tgt_set.nsip &= tgt->set.nsip; tgt->set.client_ip &= ~tgt_set.client_ip; tgt->set.ip &= ~tgt_set.ip; tgt->set.nsip &= ~tgt_set.nsip; set_sum_pair(tgt); adj_trigger_cnt(rpzs, rpz_num, rpz_type, &tgt_ip, tgt_prefix, ISC_FALSE); /* * We might need to delete 2 nodes. */ do { /* * The node is now useless if it has no data of its own * and 0 or 1 children. We are finished if it is not useless. */ if ((child = tgt->child[0]) != NULL) { if (tgt->child[1] != NULL) break; } else { child = tgt->child[1]; } if (tgt->set.client_ip != 0 || tgt->set.ip != 0 || tgt->set.nsip != 0) break; /* * Replace the pointer to this node in the parent with * the remaining child or NULL. */ parent = tgt->parent; if (parent == NULL) { rpzs->cidr = child; } else { parent->child[parent->child[1] == tgt] = child; } /* * If the child exists fix up its parent pointer. */ if (child != NULL) child->parent = parent; isc_mem_put(rpzs->mctx, tgt, sizeof(*tgt)); tgt = parent; } while (tgt != NULL); } static void del_name(dns_rpz_zones_t *rpzs, dns_rpz_num_t rpz_num, dns_rpz_type_t rpz_type, dns_name_t *src_name) { char namebuf[DNS_NAME_FORMATSIZE]; dns_fixedname_t trig_namef; dns_name_t *trig_name; dns_rbtnode_t *nmnode; dns_rpz_nm_data_t *nm_data, del_data; isc_result_t result; /* * No need for a summary database of names with only 1 policy zone. */ if (rpzs->p.num_zones <= 1) { adj_trigger_cnt(rpzs, rpz_num, rpz_type, NULL, 0, ISC_FALSE); return; } dns_fixedname_init(&trig_namef); trig_name = dns_fixedname_name(&trig_namef); name2data(rpzs, rpz_num, rpz_type, src_name, trig_name, &del_data); nmnode = NULL; result = dns_rbt_findnode(rpzs->rbt, trig_name, NULL, &nmnode, NULL, 0, NULL, NULL); if (result != ISC_R_SUCCESS) { /* * Do not worry about missing summary RBT nodes that probably * correspond to RBTDB nodes that were implicit RBT nodes * that were later added for (often empty) wildcards * and then to the RBTDB deferred cleanup list. */ if (result == ISC_R_NOTFOUND || result == DNS_R_PARTIALMATCH) return; dns_name_format(src_name, namebuf, sizeof(namebuf)); isc_log_write(dns_lctx, DNS_LOGCATEGORY_RPZ, DNS_LOGMODULE_RBTDB, DNS_RPZ_ERROR_LEVEL, "rpz del_name(%s) node search failed: %s", namebuf, isc_result_totext(result)); return; } nm_data = nmnode->data; INSIST(nm_data != NULL); /* * Do not count bits that next existed for RBT nodes that would we * would not have found in a summary for a single RBTDB tree. */ del_data.set.qname &= nm_data->set.qname; del_data.set.ns &= nm_data->set.ns; del_data.wild.qname &= nm_data->wild.qname; del_data.wild.ns &= nm_data->wild.ns; nm_data->set.qname &= ~del_data.set.qname; nm_data->set.ns &= ~del_data.set.ns; nm_data->wild.qname &= ~del_data.wild.qname; nm_data->wild.ns &= ~del_data.wild.ns; if (nm_data->set.qname == 0 && nm_data->set.ns == 0 && nm_data->wild.qname == 0 && nm_data->wild.ns == 0) { result = dns_rbt_deletenode(rpzs->rbt, nmnode, ISC_FALSE); if (result != ISC_R_SUCCESS) { /* * bin/tests/system/rpz/tests.sh looks for "rpz.*failed". */ dns_name_format(src_name, namebuf, sizeof(namebuf)); isc_log_write(dns_lctx, DNS_LOGCATEGORY_RPZ, DNS_LOGMODULE_RBTDB, DNS_RPZ_ERROR_LEVEL, "rpz del_name(%s) node delete failed: %s", namebuf, isc_result_totext(result)); } } adj_trigger_cnt(rpzs, rpz_num, rpz_type, NULL, 0, ISC_FALSE); } /* * Remove an IP address from the radix tree or a name from the summary database. */ void dns_rpz_delete(dns_rpz_zones_t *rpzs, dns_rpz_num_t rpz_num, dns_name_t *src_name) { dns_rpz_zone_t *rpz; dns_rpz_type_t rpz_type; REQUIRE(rpzs != NULL && rpz_num < rpzs->p.num_zones); rpz = rpzs->zones[rpz_num]; REQUIRE(rpz != NULL); rpz_type = type_from_name(rpz, src_name); LOCK(&rpzs->maint_lock); RWLOCK(&rpzs->search_lock, isc_rwlocktype_write); switch (rpz_type) { case DNS_RPZ_TYPE_QNAME: case DNS_RPZ_TYPE_NSDNAME: del_name(rpzs, rpz_num, rpz_type, src_name); break; case DNS_RPZ_TYPE_CLIENT_IP: case DNS_RPZ_TYPE_IP: case DNS_RPZ_TYPE_NSIP: del_cidr(rpzs, rpz_num, rpz_type, src_name); break; case DNS_RPZ_TYPE_BAD: break; } RWUNLOCK(&rpzs->search_lock, isc_rwlocktype_write); UNLOCK(&rpzs->maint_lock); } /* * Search the summary radix tree to get a relative owner name in a * policy zone relevant to a triggering IP address. * rpz_type and zbits limit the search for IP address netaddr * return the policy zone's number or DNS_RPZ_INVALID_NUM * ip_name is the relative owner name found and * *prefixp is its prefix length. */ dns_rpz_num_t dns_rpz_find_ip(dns_rpz_zones_t *rpzs, dns_rpz_type_t rpz_type, dns_rpz_zbits_t zbits, const isc_netaddr_t *netaddr, dns_name_t *ip_name, dns_rpz_prefix_t *prefixp) { dns_rpz_cidr_key_t tgt_ip; dns_rpz_addr_zbits_t tgt_set; dns_rpz_cidr_node_t *found; isc_result_t result; dns_rpz_num_t rpz_num; dns_rpz_have_t have; int i; LOCK(&rpzs->maint_lock); have = rpzs->have; UNLOCK(&rpzs->maint_lock); /* * Convert IP address to CIDR tree key. */ if (netaddr->family == AF_INET) { tgt_ip.w[0] = 0; tgt_ip.w[1] = 0; tgt_ip.w[2] = ADDR_V4MAPPED; tgt_ip.w[3] = ntohl(netaddr->type.in.s_addr); switch (rpz_type) { case DNS_RPZ_TYPE_CLIENT_IP: zbits &= have.client_ipv4; break; case DNS_RPZ_TYPE_IP: zbits &= have.ipv4; break; case DNS_RPZ_TYPE_NSIP: zbits &= have.nsipv4; break; default: INSIST(0); break; } } else if (netaddr->family == AF_INET6) { dns_rpz_cidr_key_t src_ip6; /* * Given the int aligned struct in_addr member of netaddr->type * one could cast netaddr->type.in6 to dns_rpz_cidr_key_t *, * but some people object. */ memmove(src_ip6.w, &netaddr->type.in6, sizeof(src_ip6.w)); for (i = 0; i < 4; i++) { tgt_ip.w[i] = ntohl(src_ip6.w[i]); } switch (rpz_type) { case DNS_RPZ_TYPE_CLIENT_IP: zbits &= have.client_ipv6; break; case DNS_RPZ_TYPE_IP: zbits &= have.ipv6; break; case DNS_RPZ_TYPE_NSIP: zbits &= have.nsipv6; break; default: INSIST(0); break; } } else { return (DNS_RPZ_INVALID_NUM); } if (zbits == 0) return (DNS_RPZ_INVALID_NUM); make_addr_set(&tgt_set, zbits, rpz_type); RWLOCK(&rpzs->search_lock, isc_rwlocktype_read); result = search(rpzs, &tgt_ip, 128, &tgt_set, ISC_FALSE, &found); if (result == ISC_R_NOTFOUND) { /* * There are no eligible zones for this IP address. */ RWUNLOCK(&rpzs->search_lock, isc_rwlocktype_read); return (DNS_RPZ_INVALID_NUM); } /* * Construct the trigger name for the longest matching trigger * in the first eligible zone with a match. */ *prefixp = found->prefix; switch (rpz_type) { case DNS_RPZ_TYPE_CLIENT_IP: rpz_num = zbit_to_num(found->set.client_ip & tgt_set.client_ip); break; case DNS_RPZ_TYPE_IP: rpz_num = zbit_to_num(found->set.ip & tgt_set.ip); break; case DNS_RPZ_TYPE_NSIP: rpz_num = zbit_to_num(found->set.nsip & tgt_set.nsip); break; default: INSIST(0); break; } result = ip2name(&found->ip, found->prefix, dns_rootname, ip_name); RWUNLOCK(&rpzs->search_lock, isc_rwlocktype_read); if (result != ISC_R_SUCCESS) { /* * bin/tests/system/rpz/tests.sh looks for "rpz.*failed". */ isc_log_write(dns_lctx, DNS_LOGCATEGORY_RPZ, DNS_LOGMODULE_RBTDB, DNS_RPZ_ERROR_LEVEL, "rpz ip2name() failed: %s", isc_result_totext(result)); return (DNS_RPZ_INVALID_NUM); } return (rpz_num); } /* * Search the summary radix tree for policy zones with triggers matching * a name. */ dns_rpz_zbits_t dns_rpz_find_name(dns_rpz_zones_t *rpzs, dns_rpz_type_t rpz_type, dns_rpz_zbits_t zbits, dns_name_t *trig_name) { char namebuf[DNS_NAME_FORMATSIZE]; dns_rbtnode_t *nmnode; const dns_rpz_nm_data_t *nm_data; dns_rpz_zbits_t found_zbits; isc_result_t result; if (zbits == 0) return (0); found_zbits = 0; RWLOCK(&rpzs->search_lock, isc_rwlocktype_read); nmnode = NULL; result = dns_rbt_findnode(rpzs->rbt, trig_name, NULL, &nmnode, NULL, DNS_RBTFIND_EMPTYDATA, NULL, NULL); switch (result) { case ISC_R_SUCCESS: nm_data = nmnode->data; if (nm_data != NULL) { if (rpz_type == DNS_RPZ_TYPE_QNAME) found_zbits = nm_data->set.qname; else found_zbits = nm_data->set.ns; } nmnode = nmnode->parent; /* fall thru */ case DNS_R_PARTIALMATCH: while (nmnode != NULL) { nm_data = nmnode->data; if (nm_data != NULL) { if (rpz_type == DNS_RPZ_TYPE_QNAME) found_zbits |= nm_data->wild.qname; else found_zbits |= nm_data->wild.ns; } nmnode = nmnode->parent; } break; case ISC_R_NOTFOUND: break; default: /* * bin/tests/system/rpz/tests.sh looks for "rpz.*failed". */ dns_name_format(trig_name, namebuf, sizeof(namebuf)); isc_log_write(dns_lctx, DNS_LOGCATEGORY_RPZ, DNS_LOGMODULE_RBTDB, DNS_RPZ_ERROR_LEVEL, "dns_rpz_find_name(%s) failed: %s", namebuf, isc_result_totext(result)); break; } RWUNLOCK(&rpzs->search_lock, isc_rwlocktype_read); return (zbits & found_zbits); } /* * Translate CNAME rdata to a QNAME response policy action. */ dns_rpz_policy_t dns_rpz_decode_cname(dns_rpz_zone_t *rpz, dns_rdataset_t *rdataset, dns_name_t *selfname) { dns_rdata_t rdata = DNS_RDATA_INIT; dns_rdata_cname_t cname; isc_result_t result; result = dns_rdataset_first(rdataset); INSIST(result == ISC_R_SUCCESS); dns_rdataset_current(rdataset, &rdata); result = dns_rdata_tostruct(&rdata, &cname, NULL); INSIST(result == ISC_R_SUCCESS); dns_rdata_reset(&rdata); /* * CNAME . means NXDOMAIN */ if (dns_name_equal(&cname.cname, dns_rootname)) return (DNS_RPZ_POLICY_NXDOMAIN); if (dns_name_iswildcard(&cname.cname)) { /* * CNAME *. means NODATA */ if (dns_name_countlabels(&cname.cname) == 2) return (DNS_RPZ_POLICY_NODATA); /* * A qname of www.evil.com and a policy of * *.evil.com CNAME *.garden.net * gives a result of * evil.com CNAME evil.com.garden.net */ if (dns_name_countlabels(&cname.cname) > 2) return (DNS_RPZ_POLICY_WILDCNAME); } /* * CNAME rpz-tcp-only. means "send truncated UDP responses." */ if (dns_name_equal(&cname.cname, &rpz->tcp_only)) return (DNS_RPZ_POLICY_TCP_ONLY); /* * CNAME rpz-drop. means "do not respond." */ if (dns_name_equal(&cname.cname, &rpz->drop)) return (DNS_RPZ_POLICY_DROP); /* * CNAME rpz-passthru. means "do not rewrite." */ if (dns_name_equal(&cname.cname, &rpz->passthru)) return (DNS_RPZ_POLICY_PASSTHRU); /* * 128.1.0.127.rpz-ip CNAME 128.1.0.0.127. is obsolete PASSTHRU */ if (selfname != NULL && dns_name_equal(&cname.cname, selfname)) return (DNS_RPZ_POLICY_PASSTHRU); /* * Any other rdata gives a response consisting of the rdata. */ return (DNS_RPZ_POLICY_RECORD); }