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authoranonimal <anonimal@i2pmail.org>2017-06-28 21:07:24 +0000
committeranonimal <anonimal@i2pmail.org>2018-03-18 15:52:19 +0000
commit84c5a9ba481d7a33cc0fd0ca43867b61d127d907 (patch)
treef05d3d3f107da02005b4a61f0e5074c113a7165c /external/unbound/dns64/dns64.c
parentMerge pull request #3416 (diff)
downloadmonero-84c5a9ba481d7a33cc0fd0ca43867b61d127d907.tar.xz
Unbound: remove unbound from in-tree source
We'll instead use a git submodule to pull from our unbound repo.
Diffstat (limited to 'external/unbound/dns64/dns64.c')
-rw-r--r--external/unbound/dns64/dns64.c854
1 files changed, 0 insertions, 854 deletions
diff --git a/external/unbound/dns64/dns64.c b/external/unbound/dns64/dns64.c
deleted file mode 100644
index b3e3ab852..000000000
--- a/external/unbound/dns64/dns64.c
+++ /dev/null
@@ -1,854 +0,0 @@
-/*
- * dns64/dns64.c - DNS64 module
- *
- * Copyright (c) 2009, Viagénie. All rights reserved.
- *
- * This software is open source.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * Redistributions of source code must retain the above copyright notice,
- * this list of conditions and the following disclaimer.
- *
- * Redistributions in binary form must reproduce the above copyright notice,
- * this list of conditions and the following disclaimer in the documentation
- * and/or other materials provided with the distribution.
- *
- * Neither the name of Viagénie nor the names of its contributors may
- * be used to endorse or promote products derived from this software without
- * specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
- * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE
- * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- */
-
-/**
- * \file
- *
- * This file contains a module that performs DNS64 query processing.
- */
-
-#include "config.h"
-#include "dns64/dns64.h"
-#include "services/cache/dns.h"
-#include "services/cache/rrset.h"
-#include "util/config_file.h"
-#include "util/data/msgreply.h"
-#include "util/fptr_wlist.h"
-#include "util/net_help.h"
-#include "util/regional.h"
-
-/******************************************************************************
- * *
- * STATIC CONSTANTS *
- * *
- ******************************************************************************/
-
-/**
- * This is the default DNS64 prefix that is used whent he dns64 module is listed
- * in module-config but when the dns64-prefix variable is not present.
- */
-static const char DEFAULT_DNS64_PREFIX[] = "64:ff9b::/96";
-
-/**
- * Maximum length of a domain name in a PTR query in the .in-addr.arpa tree.
- */
-#define MAX_PTR_QNAME_IPV4 30
-
-/**
- * Per-query module-specific state. This is usually a dynamically-allocated
- * structure, but in our case we only need to store one variable describing the
- * state the query is in. So we repurpose the minfo pointer by storing an
- * integer in there.
- */
-enum dns64_qstate {
- DNS64_INTERNAL_QUERY, /**< Internally-generated query, no DNS64
- processing. */
- DNS64_NEW_QUERY, /**< Query for which we're the first module in
- line. */
- DNS64_SUBQUERY_FINISHED /**< Query for which we generated a sub-query, and
- for which this sub-query is finished. */
-};
-
-
-/******************************************************************************
- * *
- * STRUCTURES *
- * *
- ******************************************************************************/
-
-/**
- * This structure contains module configuration information. One instance of
- * this structure exists per instance of the module. Normally there is only one
- * instance of the module.
- */
-struct dns64_env {
- /**
- * DNS64 prefix address. We're using a full sockaddr instead of just an
- * in6_addr because we can reuse Unbound's generic string parsing functions.
- * It will always contain a sockaddr_in6, and only the sin6_addr member will
- * ever be used.
- */
- struct sockaddr_storage prefix_addr;
-
- /**
- * This is always sizeof(sockaddr_in6).
- */
- socklen_t prefix_addrlen;
-
- /**
- * This is the CIDR length of the prefix. It needs to be between 0 and 96.
- */
- int prefix_net;
-};
-
-
-/******************************************************************************
- * *
- * UTILITY FUNCTIONS *
- * *
- ******************************************************************************/
-
-/**
- * Generic macro for swapping two variables.
- *
- * \param t Type of the variables. (e.g. int)
- * \param a First variable.
- * \param b Second variable.
- *
- * \warning Do not attempt something foolish such as swap(int,a++,b++)!
- */
-#define swap(t,a,b) do {t x = a; a = b; b = x;} while(0)
-
-/**
- * Reverses a string.
- *
- * \param begin Points to the first character of the string.
- * \param end Points one past the last character of the string.
- */
-static void
-reverse(char* begin, char* end)
-{
- while ( begin < --end ) {
- swap(char, *begin, *end);
- ++begin;
- }
-}
-
-/**
- * Convert an unsigned integer to a string. The point of this function is that
- * of being faster than sprintf().
- *
- * \param n The number to be converted.
- * \param s The result will be written here. Must be large enough, be careful!
- *
- * \return The number of characters written.
- */
-static int
-uitoa(unsigned n, char* s)
-{
- char* ss = s;
- do {
- *ss++ = '0' + n % 10;
- } while (n /= 10);
- reverse(s, ss);
- return ss - s;
-}
-
-/**
- * Extract an IPv4 address embedded in the IPv6 address \a ipv6 at offset \a
- * offset (in bits). Note that bits are not necessarily aligned on bytes so we
- * need to be careful.
- *
- * \param ipv6 IPv6 address represented as a 128-bit array in big-endian
- * order.
- * \param offset Index of the MSB of the IPv4 address embedded in the IPv6
- * address.
- */
-static uint32_t
-extract_ipv4(const uint8_t ipv6[16], const int offset)
-{
- uint32_t ipv4 = (uint32_t)ipv6[offset/8+0] << (24 + (offset%8))
- | (uint32_t)ipv6[offset/8+1] << (16 + (offset%8))
- | (uint32_t)ipv6[offset/8+2] << ( 8 + (offset%8))
- | (uint32_t)ipv6[offset/8+3] << ( 0 + (offset%8));
- if (offset/8+4 < 16)
- ipv4 |= (uint32_t)ipv6[offset/8+4] >> (8 - offset%8);
- return ipv4;
-}
-
-/**
- * Builds the PTR query name corresponding to an IPv4 address. For example,
- * given the number 3,464,175,361, this will build the string
- * "\03206\03123\0231\011\07in-addr\04arpa".
- *
- * \param ipv4 IPv4 address represented as an unsigned 32-bit number.
- * \param ptr The result will be written here. Must be large enough, be
- * careful!
- *
- * \return The number of characters written.
- */
-static size_t
-ipv4_to_ptr(uint32_t ipv4, char ptr[MAX_PTR_QNAME_IPV4])
-{
- static const char IPV4_PTR_SUFFIX[] = "\07in-addr\04arpa";
- int i;
- char* c = ptr;
-
- for (i = 0; i < 4; ++i) {
- *c = uitoa((unsigned int)(ipv4 % 256), c + 1);
- c += *c + 1;
- ipv4 /= 256;
- }
-
- memmove(c, IPV4_PTR_SUFFIX, sizeof(IPV4_PTR_SUFFIX));
-
- return c + sizeof(IPV4_PTR_SUFFIX) - ptr;
-}
-
-/**
- * Converts an IPv6-related domain name string from a PTR query into an IPv6
- * address represented as a 128-bit array.
- *
- * \param ptr The domain name. (e.g. "\011[...]\010\012\016\012\03ip6\04arpa")
- * \param ipv6 The result will be written here, in network byte order.
- *
- * \return 1 on success, 0 on failure.
- */
-static int
-ptr_to_ipv6(const char* ptr, uint8_t ipv6[16])
-{
- int i;
-
- for (i = 0; i < 64; i++) {
- int x;
-
- if (ptr[i++] != 1)
- return 0;
-
- if (ptr[i] >= '0' && ptr[i] <= '9') {
- x = ptr[i] - '0';
- } else if (ptr[i] >= 'a' && ptr[i] <= 'f') {
- x = ptr[i] - 'a' + 10;
- } else if (ptr[i] >= 'A' && ptr[i] <= 'F') {
- x = ptr[i] - 'A' + 10;
- } else {
- return 0;
- }
-
- ipv6[15-i/4] |= x << (2 * ((i-1) % 4));
- }
-
- return 1;
-}
-
-/**
- * Synthesize an IPv6 address based on an IPv4 address and the DNS64 prefix.
- *
- * \param prefix_addr DNS64 prefix address.
- * \param prefix_net CIDR length of the DNS64 prefix. Must be between 0 and 96.
- * \param a IPv4 address.
- * \param aaaa IPv6 address. The result will be written here.
- */
-static void
-synthesize_aaaa(const uint8_t prefix_addr[16], int prefix_net,
- const uint8_t a[4], uint8_t aaaa[16])
-{
- memcpy(aaaa, prefix_addr, 16);
- aaaa[prefix_net/8+0] |= a[0] >> (0+prefix_net%8);
- aaaa[prefix_net/8+1] |= a[0] << (8-prefix_net%8);
- aaaa[prefix_net/8+1] |= a[1] >> (0+prefix_net%8);
- aaaa[prefix_net/8+2] |= a[1] << (8-prefix_net%8);
- aaaa[prefix_net/8+2] |= a[2] >> (0+prefix_net%8);
- aaaa[prefix_net/8+3] |= a[2] << (8-prefix_net%8);
- aaaa[prefix_net/8+3] |= a[3] >> (0+prefix_net%8);
- if (prefix_net/8+4 < 16) /* <-- my beautiful symmetry is destroyed! */
- aaaa[prefix_net/8+4] |= a[3] << (8-prefix_net%8);
-}
-
-
-/******************************************************************************
- * *
- * DNS64 MODULE FUNCTIONS *
- * *
- ******************************************************************************/
-
-/**
- * This function applies the configuration found in the parsed configuration
- * file \a cfg to this instance of the dns64 module. Currently only the DNS64
- * prefix (a.k.a. Pref64) is configurable.
- *
- * \param dns64_env Module-specific global parameters.
- * \param cfg Parsed configuration file.
- */
-static int
-dns64_apply_cfg(struct dns64_env* dns64_env, struct config_file* cfg)
-{
- verbose(VERB_ALGO, "dns64-prefix: %s", cfg->dns64_prefix);
- if (!netblockstrtoaddr(cfg->dns64_prefix ? cfg->dns64_prefix :
- DEFAULT_DNS64_PREFIX, 0, &dns64_env->prefix_addr,
- &dns64_env->prefix_addrlen, &dns64_env->prefix_net)) {
- log_err("cannot parse dns64-prefix netblock: %s", cfg->dns64_prefix);
- return 0;
- }
- if (!addr_is_ip6(&dns64_env->prefix_addr, dns64_env->prefix_addrlen)) {
- log_err("dns64_prefix is not IPv6: %s", cfg->dns64_prefix);
- return 0;
- }
- if (dns64_env->prefix_net < 0 || dns64_env->prefix_net > 96) {
- log_err("dns64-prefix length it not between 0 and 96: %s",
- cfg->dns64_prefix);
- return 0;
- }
- return 1;
-}
-
-/**
- * Initializes this instance of the dns64 module.
- *
- * \param env Global state of all module instances.
- * \param id This instance's ID number.
- */
-int
-dns64_init(struct module_env* env, int id)
-{
- struct dns64_env* dns64_env =
- (struct dns64_env*)calloc(1, sizeof(struct dns64_env));
- if (!dns64_env) {
- log_err("malloc failure");
- return 0;
- }
- env->modinfo[id] = (void*)dns64_env;
- if (!dns64_apply_cfg(dns64_env, env->cfg)) {
- log_err("dns64: could not apply configuration settings.");
- return 0;
- }
- return 1;
-}
-
-/**
- * Deinitializes this instance of the dns64 module.
- *
- * \param env Global state of all module instances.
- * \param id This instance's ID number.
- */
-void
-dns64_deinit(struct module_env* env, int id)
-{
- if (!env)
- return;
- free(env->modinfo[id]);
- env->modinfo[id] = NULL;
-}
-
-/**
- * Handle PTR queries for IPv6 addresses. If the address belongs to the DNS64
- * prefix, we must do a PTR query for the corresponding IPv4 address instead.
- *
- * \param qstate Query state structure.
- * \param id This module instance's ID number.
- *
- * \return The new state of the query.
- */
-static enum module_ext_state
-handle_ipv6_ptr(struct module_qstate* qstate, int id)
-{
- struct dns64_env* dns64_env = (struct dns64_env*)qstate->env->modinfo[id];
- struct module_qstate* subq = NULL;
- struct query_info qinfo;
- struct sockaddr_in6 sin6;
-
- /* Convert the PTR query string to an IPv6 address. */
- memset(&sin6, 0, sizeof(sin6));
- sin6.sin6_family = AF_INET6;
- if (!ptr_to_ipv6((char*)qstate->qinfo.qname, sin6.sin6_addr.s6_addr))
- return module_wait_module; /* Let other module handle this. */
-
- /*
- * If this IPv6 address is not part of our DNS64 prefix, then we don't need
- * to do anything. Let another module handle the query.
- */
- if (addr_in_common((struct sockaddr_storage*)&sin6, 128,
- &dns64_env->prefix_addr, dns64_env->prefix_net,
- (socklen_t)sizeof(sin6)) != dns64_env->prefix_net)
- return module_wait_module;
-
- verbose(VERB_ALGO, "dns64: rewrite PTR record");
-
- /*
- * Create a new PTR query info for the domain name corresponding to the IPv4
- * address corresponding to the IPv6 address corresponding to the original
- * PTR query domain name.
- */
- qinfo = qstate->qinfo;
- if (!(qinfo.qname = regional_alloc(qstate->region, MAX_PTR_QNAME_IPV4)))
- return module_error;
- qinfo.qname_len = ipv4_to_ptr(extract_ipv4(sin6.sin6_addr.s6_addr,
- dns64_env->prefix_net), (char*)qinfo.qname);
-
- /* Create the new sub-query. */
- fptr_ok(fptr_whitelist_modenv_attach_sub(qstate->env->attach_sub));
- if(!(*qstate->env->attach_sub)(qstate, &qinfo, qstate->query_flags, 0, 0,
- &subq))
- return module_error;
- if (subq) {
- subq->curmod = id;
- subq->ext_state[id] = module_state_initial;
- subq->minfo[id] = NULL;
- }
-
- return module_wait_subquery;
-}
-
-static enum module_ext_state
-generate_type_A_query(struct module_qstate* qstate, int id)
-{
- struct module_qstate* subq = NULL;
- struct query_info qinfo;
-
- verbose(VERB_ALGO, "dns64: query A record");
-
- /* Create a new query info. */
- qinfo = qstate->qinfo;
- qinfo.qtype = LDNS_RR_TYPE_A;
-
- /* Start the sub-query. */
- fptr_ok(fptr_whitelist_modenv_attach_sub(qstate->env->attach_sub));
- if(!(*qstate->env->attach_sub)(qstate, &qinfo, qstate->query_flags, 0,
- 0, &subq))
- {
- verbose(VERB_ALGO, "dns64: sub-query creation failed");
- return module_error;
- }
- if (subq) {
- subq->curmod = id;
- subq->ext_state[id] = module_state_initial;
- subq->minfo[id] = NULL;
- }
-
- return module_wait_subquery;
-}
-
-/**
- * Handles the "pass" event for a query. This event is received when a new query
- * is received by this module. The query may have been generated internally by
- * another module, in which case we don't want to do any special processing
- * (this is an interesting discussion topic), or it may be brand new, e.g.
- * received over a socket, in which case we do want to apply DNS64 processing.
- *
- * \param qstate A structure representing the state of the query that has just
- * received the "pass" event.
- * \param id This module's instance ID.
- *
- * \return The new state of the query.
- */
-static enum module_ext_state
-handle_event_pass(struct module_qstate* qstate, int id)
-{
- if ((uintptr_t)qstate->minfo[id] == DNS64_NEW_QUERY
- && qstate->qinfo.qtype == LDNS_RR_TYPE_PTR
- && qstate->qinfo.qname_len == 74
- && !strcmp((char*)&qstate->qinfo.qname[64], "\03ip6\04arpa"))
- /* Handle PTR queries for IPv6 addresses. */
- return handle_ipv6_ptr(qstate, id);
-
- if (qstate->env->cfg->dns64_synthall &&
- (uintptr_t)qstate->minfo[id] == DNS64_NEW_QUERY
- && qstate->qinfo.qtype == LDNS_RR_TYPE_AAAA)
- return generate_type_A_query(qstate, id);
-
- /* We are finished when our sub-query is finished. */
- if ((uintptr_t)qstate->minfo[id] == DNS64_SUBQUERY_FINISHED)
- return module_finished;
-
- /* Otherwise, pass request to next module. */
- verbose(VERB_ALGO, "dns64: pass to next module");
- return module_wait_module;
-}
-
-/**
- * Handles the "done" event for a query. We need to analyze the response and
- * maybe issue a new sub-query for the A record.
- *
- * \param qstate A structure representing the state of the query that has just
- * received the "pass" event.
- * \param id This module's instance ID.
- *
- * \return The new state of the query.
- */
-static enum module_ext_state
-handle_event_moddone(struct module_qstate* qstate, int id)
-{
- /*
- * In many cases we have nothing special to do. From most to least common:
- *
- * - An internal query.
- * - A query for a record type other than AAAA.
- * - CD FLAG was set on querier
- * - An AAAA query for which an error was returned.(qstate.return_rcode)
- * -> treated as servfail thus synthesize (sec 5.1.3 6147), thus
- * synthesize in (sec 5.1.2 of RFC6147).
- * - A successful AAAA query with an answer.
- */
- if ( (enum dns64_qstate)qstate->minfo[id] == DNS64_INTERNAL_QUERY
- || qstate->qinfo.qtype != LDNS_RR_TYPE_AAAA
- || (qstate->query_flags & BIT_CD)
- || (qstate->return_msg &&
- qstate->return_msg->rep &&
- reply_find_answer_rrset(&qstate->qinfo,
- qstate->return_msg->rep)))
- return module_finished;
-
- /* So, this is a AAAA noerror/nodata answer */
- return generate_type_A_query(qstate, id);
-}
-
-/**
- * This is the module's main() function. It gets called each time a query
- * receives an event which we may need to handle. We respond by updating the
- * state of the query.
- *
- * \param qstate Structure containing the state of the query.
- * \param event Event that has just been received.
- * \param id This module's instance ID.
- * \param outbound State of a DNS query on an authoritative server. We never do
- * our own queries ourselves (other modules do it for us), so
- * this is unused.
- */
-void
-dns64_operate(struct module_qstate* qstate, enum module_ev event, int id,
- struct outbound_entry* outbound)
-{
- (void)outbound;
- verbose(VERB_QUERY, "dns64[module %d] operate: extstate:%s event:%s",
- id, strextstate(qstate->ext_state[id]),
- strmodulevent(event));
- log_query_info(VERB_QUERY, "dns64 operate: query", &qstate->qinfo);
-
- switch(event) {
- case module_event_new:
- /* Tag this query as being new and fall through. */
- qstate->minfo[id] = (void*)DNS64_NEW_QUERY;
- case module_event_pass:
- qstate->ext_state[id] = handle_event_pass(qstate, id);
- break;
- case module_event_moddone:
- qstate->ext_state[id] = handle_event_moddone(qstate, id);
- break;
- default:
- qstate->ext_state[id] = module_finished;
- break;
- }
-}
-
-static void
-dns64_synth_aaaa_data(const struct ub_packed_rrset_key* fk,
- const struct packed_rrset_data* fd,
- struct ub_packed_rrset_key *dk,
- struct packed_rrset_data **dd_out, struct regional *region,
- struct dns64_env* dns64_env )
-{
- struct packed_rrset_data *dd;
- size_t i;
- /*
- * Create synthesized AAAA RR set data. We need to allocated extra memory
- * for the RRs themselves. Each RR has a length, TTL, pointer to wireformat
- * data, 2 bytes of data length, and 16 bytes of IPv6 address.
- */
- if(fd->count > RR_COUNT_MAX) {
- *dd_out = NULL;
- return; /* integer overflow protection in alloc */
- }
- if (!(dd = *dd_out = regional_alloc(region,
- sizeof(struct packed_rrset_data)
- + fd->count * (sizeof(size_t) + sizeof(time_t) +
- sizeof(uint8_t*) + 2 + 16)))) {
- log_err("out of memory");
- return;
- }
-
- /* Copy attributes from A RR set. */
- dd->ttl = fd->ttl;
- dd->count = fd->count;
- dd->rrsig_count = 0;
- dd->trust = fd->trust;
- dd->security = fd->security;
-
- /*
- * Synthesize AAAA records. Adjust pointers in structure.
- */
- dd->rr_len =
- (size_t*)((uint8_t*)dd + sizeof(struct packed_rrset_data));
- dd->rr_data = (uint8_t**)&dd->rr_len[dd->count];
- dd->rr_ttl = (time_t*)&dd->rr_data[dd->count];
- for(i = 0; i < fd->count; ++i) {
- if (fd->rr_len[i] != 6 || fd->rr_data[i][0] != 0
- || fd->rr_data[i][1] != 4) {
- *dd_out = NULL;
- return;
- }
- dd->rr_len[i] = 18;
- dd->rr_data[i] =
- (uint8_t*)&dd->rr_ttl[dd->count] + 18*i;
- dd->rr_data[i][0] = 0;
- dd->rr_data[i][1] = 16;
- synthesize_aaaa(
- ((struct sockaddr_in6*)&dns64_env->prefix_addr)->sin6_addr.s6_addr,
- dns64_env->prefix_net, &fd->rr_data[i][2],
- &dd->rr_data[i][2] );
- dd->rr_ttl[i] = fd->rr_ttl[i];
- }
-
- /*
- * Create synthesized AAAA RR set key. This is mostly just bookkeeping,
- * nothing interesting here.
- */
- if(!dk) {
- log_err("no key");
- *dd_out = NULL;
- return;
- }
-
- dk->rk.dname = (uint8_t*)regional_alloc_init(region,
- fk->rk.dname, fk->rk.dname_len);
-
- if(!dk->rk.dname) {
- log_err("out of memory");
- *dd_out = NULL;
- return;
- }
-
- dk->rk.type = htons(LDNS_RR_TYPE_AAAA);
- memset(&dk->entry, 0, sizeof(dk->entry));
- dk->entry.key = dk;
- dk->entry.hash = rrset_key_hash(&dk->rk);
- dk->entry.data = dd;
-
-}
-
-/**
- * Synthesize an AAAA RR set from an A sub-query's answer and add it to the
- * original empty response.
- *
- * \param id This module's instance ID.
- * \param super Original AAAA query.
- * \param qstate A query.
- */
-static void
-dns64_adjust_a(int id, struct module_qstate* super, struct module_qstate* qstate)
-{
- struct dns64_env* dns64_env = (struct dns64_env*)super->env->modinfo[id];
- struct reply_info *rep, *cp;
- size_t i, s;
- struct packed_rrset_data* fd, *dd;
- struct ub_packed_rrset_key* fk, *dk;
-
- verbose(VERB_ALGO, "converting A answers to AAAA answers");
-
- log_assert(super->region);
- log_assert(qstate->return_msg);
- log_assert(qstate->return_msg->rep);
-
- /* If dns64-synthall is enabled, return_msg is not initialized */
- if(!super->return_msg) {
- super->return_msg = (struct dns_msg*)regional_alloc(
- super->region, sizeof(struct dns_msg));
- if(!super->return_msg)
- return;
- memset(super->return_msg, 0, sizeof(*super->return_msg));
- super->return_msg->qinfo = super->qinfo;
- }
-
- rep = qstate->return_msg->rep;
-
- /*
- * Build the actual reply.
- */
- cp = construct_reply_info_base(super->region, rep->flags, rep->qdcount,
- rep->ttl, rep->prefetch_ttl, rep->an_numrrsets, rep->ns_numrrsets,
- rep->ar_numrrsets, rep->rrset_count, rep->security);
- if(!cp)
- return;
-
- /* allocate ub_key structures special or not */
- if(!reply_info_alloc_rrset_keys(cp, NULL, super->region)) {
- return;
- }
-
- /* copy everything and replace A by AAAA */
- for(i=0; i<cp->rrset_count; i++) {
- fk = rep->rrsets[i];
- dk = cp->rrsets[i];
- fd = (struct packed_rrset_data*)fk->entry.data;
- dk->rk = fk->rk;
- dk->id = fk->id;
-
- if(i<rep->an_numrrsets && fk->rk.type == htons(LDNS_RR_TYPE_A)) {
- /* also sets dk->entry.hash */
- dns64_synth_aaaa_data(fk, fd, dk, &dd, super->region, dns64_env);
- if(!dd)
- return;
- /* Delete negative AAAA record from cache stored by
- * the iterator module */
- rrset_cache_remove(super->env->rrset_cache, dk->rk.dname,
- dk->rk.dname_len, LDNS_RR_TYPE_AAAA,
- LDNS_RR_CLASS_IN, 0);
- } else {
- dk->entry.hash = fk->entry.hash;
- dk->rk.dname = (uint8_t*)regional_alloc_init(super->region,
- fk->rk.dname, fk->rk.dname_len);
-
- if(!dk->rk.dname)
- return;
-
- s = packed_rrset_sizeof(fd);
- dd = (struct packed_rrset_data*)regional_alloc_init(
- super->region, fd, s);
-
- if(!dd)
- return;
- }
-
- packed_rrset_ptr_fixup(dd);
- dk->entry.data = (void*)dd;
- }
-
- /* Commit changes. */
- super->return_msg->rep = cp;
-}
-
-/**
- * Generate a response for the original IPv6 PTR query based on an IPv4 PTR
- * sub-query's response.
- *
- * \param qstate IPv4 PTR sub-query.
- * \param super Original IPv6 PTR query.
- */
-static void
-dns64_adjust_ptr(struct module_qstate* qstate, struct module_qstate* super)
-{
- struct ub_packed_rrset_key* answer;
-
- verbose(VERB_ALGO, "adjusting PTR reply");
-
- /* Copy the sub-query's reply to the parent. */
- if (!(super->return_msg = (struct dns_msg*)regional_alloc(super->region,
- sizeof(struct dns_msg))))
- return;
- super->return_msg->qinfo = super->qinfo;
- super->return_msg->rep = reply_info_copy(qstate->return_msg->rep, NULL,
- super->region);
-
- /*
- * Adjust the domain name of the answer RR set so that it matches the
- * initial query's domain name.
- */
- answer = reply_find_answer_rrset(&qstate->qinfo, super->return_msg->rep);
- log_assert(answer);
- answer->rk.dname = super->qinfo.qname;
- answer->rk.dname_len = super->qinfo.qname_len;
-}
-
-/**
- * This function is called when a sub-query finishes to inform the parent query.
- *
- * We issue two kinds of sub-queries: PTR and A.
- *
- * \param qstate State of the sub-query.
- * \param id This module's instance ID.
- * \param super State of the super-query.
- */
-void
-dns64_inform_super(struct module_qstate* qstate, int id,
- struct module_qstate* super)
-{
- log_query_info(VERB_ALGO, "dns64: inform_super, sub is",
- &qstate->qinfo);
- log_query_info(VERB_ALGO, "super is", &super->qinfo);
-
- /*
- * Signal that the sub-query is finished, no matter whether we are
- * successful or not. This lets the state machine terminate.
- */
- super->minfo[id] = (void*)DNS64_SUBQUERY_FINISHED;
-
- /* If there is no successful answer, we're done. */
- if (qstate->return_rcode != LDNS_RCODE_NOERROR
- || !qstate->return_msg
- || !qstate->return_msg->rep
- || !reply_find_answer_rrset(&qstate->qinfo,
- qstate->return_msg->rep))
- return;
-
- /* Generate a response suitable for the original query. */
- if (qstate->qinfo.qtype == LDNS_RR_TYPE_A) {
- dns64_adjust_a(id, super, qstate);
- } else {
- log_assert(qstate->qinfo.qtype == LDNS_RR_TYPE_PTR);
- dns64_adjust_ptr(qstate, super);
- }
-
- /* Store the generated response in cache. */
- if (!super->no_cache_store &&
- !dns_cache_store(super->env, &super->qinfo, super->return_msg->rep,
- 0, 0, 0, NULL, super->query_flags))
- log_err("out of memory");
-}
-
-/**
- * Clear module-specific data from query state. Since we do not allocate memory,
- * it's just a matter of setting a pointer to NULL.
- *
- * \param qstate Query state.
- * \param id This module's instance ID.
- */
-void
-dns64_clear(struct module_qstate* qstate, int id)
-{
- qstate->minfo[id] = NULL;
-}
-
-/**
- * Returns the amount of global memory that this module uses, not including
- * per-query data.
- *
- * \param env Module environment.
- * \param id This module's instance ID.
- */
-size_t
-dns64_get_mem(struct module_env* env, int id)
-{
- struct dns64_env* dns64_env = (struct dns64_env*)env->modinfo[id];
- if (!dns64_env)
- return 0;
- return sizeof(*dns64_env);
-}
-
-/**
- * The dns64 function block.
- */
-static struct module_func_block dns64_block = {
- "dns64",
- &dns64_init, &dns64_deinit, &dns64_operate, &dns64_inform_super,
- &dns64_clear, &dns64_get_mem
-};
-
-/**
- * Function for returning the above function block.
- */
-struct module_func_block *
-dns64_get_funcblock(void)
-{
- return &dns64_block;
-}