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import of dnsmasq-2.56.tar.gz

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This commit is contained in:
Simon Kelley
2011-02-14 20:19:14 +00:00
parent c52e189734
commit 28866e9567
39 changed files with 5141 additions and 4286 deletions
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166
src/forward.c
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@@ -1,4 +1,4 @@
/* dnsmasq is Copyright (c) 2000-2010 Simon Kelley
/* dnsmasq is Copyright (c) 2000-2011 Simon Kelley
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
@@ -111,8 +111,8 @@ static void send_from(int fd, int nowild, char *packet, size_t len,
}
}
static unsigned short search_servers(time_t now, struct all_addr **addrpp,
unsigned short qtype, char *qdomain, int *type, char **domain, int *norebind)
static unsigned int search_servers(time_t now, struct all_addr **addrpp,
unsigned int qtype, char *qdomain, int *type, char **domain, int *norebind)
{
/* If the query ends in the domain in one of our servers, set
@@ -122,13 +122,13 @@ static unsigned short search_servers(time_t now, struct all_addr **addrpp,
unsigned int namelen = strlen(qdomain);
unsigned int matchlen = 0;
struct server *serv;
unsigned short flags = 0;
unsigned int flags = 0;
for (serv = daemon->servers; serv; serv=serv->next)
/* domain matches take priority over NODOTS matches */
if ((serv->flags & SERV_FOR_NODOTS) && *type != SERV_HAS_DOMAIN && !strchr(qdomain, '.') && namelen != 0)
{
unsigned short sflag = serv->addr.sa.sa_family == AF_INET ? F_IPV4 : F_IPV6;
unsigned int sflag = serv->addr.sa.sa_family == AF_INET ? F_IPV4 : F_IPV6;
*type = SERV_FOR_NODOTS;
if (serv->flags & SERV_NO_ADDR)
flags = F_NXDOMAIN;
@@ -158,37 +158,57 @@ static unsigned short search_servers(time_t now, struct all_addr **addrpp,
{
if (serv->flags & SERV_NO_REBIND)
*norebind = 1;
else if (domainlen >= matchlen)
else
{
unsigned short sflag = serv->addr.sa.sa_family == AF_INET ? F_IPV4 : F_IPV6;
*type = serv->flags & (SERV_HAS_DOMAIN | SERV_USE_RESOLV | SERV_NO_REBIND);
*domain = serv->domain;
matchlen = domainlen;
if (serv->flags & SERV_NO_ADDR)
flags = F_NXDOMAIN;
else if (serv->flags & SERV_LITERAL_ADDRESS)
unsigned int sflag = serv->addr.sa.sa_family == AF_INET ? F_IPV4 : F_IPV6;
/* implement priority rules for --address and --server for same domain.
--address wins if the address is for the correct AF
--server wins otherwise. */
if (domainlen != 0 && domainlen == matchlen)
{
if (sflag & qtype)
if ((serv->flags & SERV_LITERAL_ADDRESS))
{
flags = sflag;
if (serv->addr.sa.sa_family == AF_INET)
*addrpp = (struct all_addr *)&serv->addr.in.sin_addr;
#ifdef HAVE_IPV6
else
*addrpp = (struct all_addr *)&serv->addr.in6.sin6_addr;
#endif
if (!(sflag & qtype) && flags == 0)
continue;
}
else
{
if (flags & (F_IPV4 | F_IPV6))
continue;
}
else if (!flags || (flags & F_NXDOMAIN))
flags = F_NOERR;
}
else
flags = 0;
}
if (domainlen >= matchlen)
{
*type = serv->flags & (SERV_HAS_DOMAIN | SERV_USE_RESOLV | SERV_NO_REBIND);
*domain = serv->domain;
matchlen = domainlen;
if (serv->flags & SERV_NO_ADDR)
flags = F_NXDOMAIN;
else if (serv->flags & SERV_LITERAL_ADDRESS)
{
if (sflag & qtype)
{
flags = sflag;
if (serv->addr.sa.sa_family == AF_INET)
*addrpp = (struct all_addr *)&serv->addr.in.sin_addr;
#ifdef HAVE_IPV6
else
*addrpp = (struct all_addr *)&serv->addr.in6.sin6_addr;
#endif
}
else if (!flags || (flags & F_NXDOMAIN))
flags = F_NOERR;
}
else
flags = 0;
}
}
}
}
if (flags == 0 && !(qtype & F_BIGNAME) &&
(daemon->options & OPT_NODOTS_LOCAL) && !strchr(qdomain, '.') && namelen != 0)
if (flags == 0 && !(qtype & F_NSRR) &&
option_bool(OPT_NODOTS_LOCAL) && !strchr(qdomain, '.') && namelen != 0)
/* don't forward simple names, make exception for NS queries and empty name. */
flags = F_NXDOMAIN;
@@ -220,10 +240,13 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
int type = 0, norebind = 0;
struct all_addr *addrp = NULL;
unsigned int crc = questions_crc(header, plen, daemon->namebuff);
unsigned short flags = 0;
unsigned short gotname = extract_request(header, plen, daemon->namebuff, NULL);
unsigned int flags = 0;
unsigned int gotname = extract_request(header, plen, daemon->namebuff, NULL);
struct server *start = NULL;
/* RFC 4035: sect 4.6 para 2 */
header->ad = 0;
/* may be no servers available. */
if (!daemon->servers)
forward = NULL;
@@ -232,7 +255,7 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
/* retry on existing query, send to all available servers */
domain = forward->sentto->domain;
forward->sentto->failed_queries++;
if (!(daemon->options & OPT_ORDER))
if (!option_bool(OPT_ORDER))
{
forward->forwardall = 1;
daemon->last_server = NULL;
@@ -261,9 +284,13 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
forward->fd = udpfd;
forward->crc = crc;
forward->forwardall = 0;
forward->norebind = norebind;
header->id = htons(forward->new_id);
if (norebind)
forward->flags |= FREC_NOREBIND;
if (header->cd)
forward->flags |= FREC_CHECKING_DISABLED;
header->id = htons(forward->new_id);
/* In strict_order mode, always try servers in the order
specified in resolv.conf, if a domain is given
always try all the available servers,
@@ -271,7 +298,7 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
if (type == 0)
{
if (daemon->options & OPT_ORDER)
if (option_bool(OPT_ORDER))
start = daemon->servers;
else if (!(start = daemon->last_server) ||
daemon->forwardcount++ > FORWARD_TEST ||
@@ -286,7 +313,7 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
else
{
start = daemon->servers;
if (!(daemon->options & OPT_ORDER))
if (!option_bool(OPT_ORDER))
forward->forwardall = 1;
}
}
@@ -300,7 +327,10 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
{
struct server *firstsentto = start;
int forwarded = 0;
if (udpaddr && option_bool(OPT_ADD_MAC))
plen = add_mac(header, plen, ((char *) header) + PACKETSZ, udpaddr);
while (1)
{
/* only send to servers dealing with our domain.
@@ -389,14 +419,14 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
if (udpfd != -1)
{
plen = setup_reply(header, plen, addrp, flags, daemon->local_ttl);
send_from(udpfd, daemon->options & OPT_NOWILD, (char *)header, plen, udpaddr, dst_addr, dst_iface);
send_from(udpfd, option_bool(OPT_NOWILD), (char *)header, plen, udpaddr, dst_addr, dst_iface);
}
return 0;
}
static size_t process_reply(HEADER *header, time_t now,
struct server *server, size_t n, int check_rebind)
struct server *server, size_t n, int check_rebind, int checking_disabled)
{
unsigned char *pheader, *sizep;
int munged = 0, is_sign;
@@ -416,6 +446,10 @@ static size_t process_reply(HEADER *header, time_t now,
PUTSHORT(daemon->edns_pktsz, psave);
}
/* RFC 4035 sect 4.6 para 3 */
if (!is_sign && !option_bool(OPT_DNSSEC))
header->ad = 0;
if (header->opcode != QUERY || (header->rcode != NOERROR && header->rcode != NXDOMAIN))
return n;
@@ -425,7 +459,7 @@ static size_t process_reply(HEADER *header, time_t now,
{
prettyprint_addr(&server->addr, daemon->namebuff);
my_syslog(LOG_WARNING, _("nameserver %s refused to do a recursive query"), daemon->namebuff);
if (!(daemon->options & OPT_LOG))
if (!option_bool(OPT_LOG))
server->flags |= SERV_WARNED_RECURSIVE;
}
@@ -450,7 +484,7 @@ static size_t process_reply(HEADER *header, time_t now,
header->rcode = NOERROR;
}
if (extract_addresses(header, n, daemon->namebuff, now, is_sign, check_rebind))
if (extract_addresses(header, n, daemon->namebuff, now, is_sign, check_rebind, checking_disabled))
{
my_syslog(LOG_WARNING, _("possible DNS-rebind attack detected: %s"), daemon->namebuff);
munged = 1;
@@ -512,7 +546,7 @@ void reply_query(int fd, int family, time_t now)
server = forward->sentto;
if ((header->rcode == SERVFAIL || header->rcode == REFUSED) &&
!(daemon->options & OPT_ORDER) &&
!option_bool(OPT_ORDER) &&
forward->forwardall == 0)
/* for broken servers, attempt to send to another one. */
{
@@ -554,7 +588,7 @@ void reply_query(int fd, int family, time_t now)
break;
}
}
if (!(daemon->options & OPT_ALL_SERVERS))
if (!option_bool(OPT_ALL_SERVERS))
daemon->last_server = server;
}
@@ -565,16 +599,16 @@ void reply_query(int fd, int family, time_t now)
if (forward->forwardall == 0 || --forward->forwardall == 1 ||
(header->rcode != REFUSED && header->rcode != SERVFAIL))
{
int check_rebind = !forward->norebind;
int check_rebind = !(forward->flags & FREC_NOREBIND);
if (!(daemon->options & OPT_NO_REBIND))
if (!option_bool(OPT_NO_REBIND))
check_rebind = 0;
if ((nn = process_reply(header, now, server, (size_t)n, check_rebind)))
if ((nn = process_reply(header, now, server, (size_t)n, check_rebind, forward->flags & FREC_CHECKING_DISABLED)))
{
header->id = htons(forward->orig_id);
header->ra = 1; /* recursion if available */
send_from(forward->fd, daemon->options & OPT_NOWILD, daemon->packet, nn,
send_from(forward->fd, option_bool(OPT_NOWILD), daemon->packet, nn,
&forward->source, &forward->dest, forward->iface);
}
free_frec(forward); /* cancel */
@@ -614,7 +648,7 @@ void receive_query(struct listener *listen, time_t now)
/* packet buffer overwritten */
daemon->srv_save = NULL;
if (listen->family == AF_INET && (daemon->options & OPT_NOWILD))
if (listen->family == AF_INET && option_bool(OPT_NOWILD))
{
dst_addr_4 = listen->iface->addr.in.sin_addr;
netmask = listen->iface->netmask;
@@ -649,8 +683,8 @@ void receive_query(struct listener *listen, time_t now)
if (listen->family == AF_INET6)
source_addr.in6.sin6_flowinfo = 0;
#endif
if (!(daemon->options & OPT_NOWILD))
if (!option_bool(OPT_NOWILD))
{
struct ifreq ifr;
@@ -721,7 +755,7 @@ void receive_query(struct listener *listen, time_t now)
return;
if (listen->family == AF_INET &&
(daemon->options & OPT_LOCALISE) &&
option_bool(OPT_LOCALISE) &&
ioctl(listen->fd, SIOCGIFNETMASK, &ifr) == -1)
return;
@@ -748,7 +782,7 @@ void receive_query(struct listener *listen, time_t now)
dst_addr_4, netmask, now);
if (m >= 1)
{
send_from(listen->fd, daemon->options & OPT_NOWILD, (char *)header,
send_from(listen->fd, option_bool(OPT_NOWILD), (char *)header,
m, &source_addr, &dst_addr, if_index);
daemon->local_answer++;
}
@@ -766,7 +800,9 @@ void receive_query(struct listener *listen, time_t now)
unsigned char *tcp_request(int confd, time_t now,
struct in_addr local_addr, struct in_addr netmask)
{
int size = 0, norebind = 0;
size_t size = 0;
int norebind = 0;
int checking_disabled;
size_t m;
unsigned short qtype, gotname;
unsigned char c1, c2;
@@ -787,6 +823,12 @@ unsigned char *tcp_request(int confd, time_t now,
continue;
header = (HEADER *)packet;
/* save state of "cd" flag in query */
checking_disabled = header->cd;
/* RFC 4035: sect 4.6 para 2 */
header->ad = 0;
if ((gotname = extract_request(header, (unsigned int)size, daemon->namebuff, &qtype)))
{
@@ -819,15 +861,24 @@ unsigned char *tcp_request(int confd, time_t now,
if (m == 0)
{
unsigned short flags = 0;
unsigned int flags = 0;
struct all_addr *addrp = NULL;
int type = 0;
char *domain = NULL;
if (option_bool(OPT_ADD_MAC))
{
union mysockaddr peer_addr;
socklen_t peer_len = sizeof(union mysockaddr);
if (getpeername(confd, (struct sockaddr *)&peer_addr, &peer_len) != -1)
size = add_mac(header, size, ((char *) header) + 65536, &peer_addr);
}
if (gotname)
flags = search_servers(now, &addrp, gotname, daemon->namebuff, &type, &domain, &norebind);
if (type != 0 || (daemon->options & OPT_ORDER) || !daemon->last_server)
if (type != 0 || option_bool(OPT_ORDER) || !daemon->last_server)
last_server = daemon->servers;
else
last_server = daemon->last_server;
@@ -906,7 +957,8 @@ unsigned char *tcp_request(int confd, time_t now,
someone might be attempting to insert bogus values into the cache by
sending replies containing questions and bogus answers. */
if (crc == questions_crc(header, (unsigned int)m, daemon->namebuff))
m = process_reply(header, now, last_server, (unsigned int)m, (daemon->options & OPT_NO_REBIND) && !norebind );
m = process_reply(header, now, last_server, (unsigned int)m,
option_bool(OPT_NO_REBIND) && !norebind, checking_disabled);
break;
}
@@ -938,6 +990,7 @@ static struct frec *allocate_frec(time_t now)
f->time = now;
f->sentto = NULL;
f->rfd4 = NULL;
f->flags = 0;
#ifdef HAVE_IPV6
f->rfd6 = NULL;
#endif
@@ -990,6 +1043,7 @@ static void free_frec(struct frec *f)
f->rfd4 = NULL;
f->sentto = NULL;
f->flags = 0;
#ifdef HAVE_IPV6
if (f->rfd6 && --(f->rfd6->refcount) == 0)