From 602a2b6481587b7da2594db39151ec9380f276df Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Tue, 10 May 2005 20:11:18 +0000 Subject: [PATCH] * abstract MTU stuff for packet generation * unicast response support * legacy unicast support git-svn-id: file:///home/lennart/svn/public/avahi/trunk@66 941a03a8-eaeb-0310-b9a0-b1bbd8fe43fe --- avahi-core/Makefile.am | 5 +++ avahi-core/dns-test.c | 2 +- avahi-core/dns.c | 62 +++++++++++++++++++++++---- avahi-core/dns.h | 11 +++-- avahi-core/iface.c | 49 +++++++++++++++------- avahi-core/iface.h | 7 ++-- avahi-core/psched.c | 29 +++++++------ avahi-core/psched.h | 6 +-- avahi-core/server.c | 95 ++++++++++++++++++++++++++++++++++++++++-- avahi-core/server.h | 3 ++ avahi-core/socket.c | 49 ++++++++++++++++------ avahi-core/socket.h | 4 +- todo | 5 +-- 13 files changed, 259 insertions(+), 68 deletions(-) diff --git a/avahi-core/Makefile.am b/avahi-core/Makefile.am index 31268e8..512b7e3 100644 --- a/avahi-core/Makefile.am +++ b/avahi-core/Makefile.am @@ -86,3 +86,8 @@ avahi_test_CFLAGS = $(AM_CFLAGS) avahi_test_LDADD = $(AM_LDADD) libavahi-core.la +valgrind: avahi-test + libtool --mode=execute valgrind ./avahi-test + +gdb: avahi-test + libtool --mode=execute gdb ./avahi-test diff --git a/avahi-core/dns-test.c b/avahi-core/dns-test.c index e0680c2..aa36f2a 100644 --- a/avahi-core/dns-test.c +++ b/avahi-core/dns-test.c @@ -30,7 +30,7 @@ int main(int argc, char *argv[]) { gchar t[256], *a, *b, *c, *d; AvahiDnsPacket *p; - p = avahi_dns_packet_new(8000); + p = avahi_dns_packet_new(0); avahi_dns_packet_append_name(p, a = "hello.hello.hello.de."); avahi_dns_packet_append_name(p, b = "this is a test.hello.de."); diff --git a/avahi-core/dns.c b/avahi-core/dns.c index cc1463a..3435a0d 100644 --- a/avahi-core/dns.c +++ b/avahi-core/dns.c @@ -32,12 +32,18 @@ #include "dns.h" #include "util.h" -AvahiDnsPacket* avahi_dns_packet_new(guint max_size) { +AvahiDnsPacket* avahi_dns_packet_new(guint mtu) { AvahiDnsPacket *p; + guint max_size; - if (max_size <= 0) + if (mtu <= 0) max_size = AVAHI_DNS_PACKET_MAX_SIZE; - else if (max_size < AVAHI_DNS_PACKET_HEADER_SIZE) + else if (mtu >= 48) + max_size = mtu - 48; + else + max_size = 0; + + if (max_size < AVAHI_DNS_PACKET_HEADER_SIZE) max_size = AVAHI_DNS_PACKET_HEADER_SIZE; p = g_malloc(sizeof(AvahiDnsPacket) + max_size); @@ -49,22 +55,60 @@ AvahiDnsPacket* avahi_dns_packet_new(guint max_size) { return p; } -AvahiDnsPacket* avahi_dns_packet_new_query(guint max_size) { +AvahiDnsPacket* avahi_dns_packet_new_query(guint mtu) { AvahiDnsPacket *p; - p = avahi_dns_packet_new(max_size); + p = avahi_dns_packet_new(mtu); avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_FLAGS, AVAHI_DNS_FLAGS(0, 0, 0, 0, 0, 0, 0, 0, 0, 0)); return p; } -AvahiDnsPacket* avahi_dns_packet_new_response(guint max_size) { +AvahiDnsPacket* avahi_dns_packet_new_response(guint mtu) { AvahiDnsPacket *p; - p = avahi_dns_packet_new(max_size); + p = avahi_dns_packet_new(mtu); avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_FLAGS, AVAHI_DNS_FLAGS(1, 0, 0, 0, 0, 0, 0, 0, 0, 0)); return p; } +AvahiDnsPacket* avahi_dns_packet_new_reply(AvahiDnsPacket* p, guint mtu, gboolean copy_queries, gboolean aa) { + AvahiDnsPacket *r; + g_assert(p); + + r = avahi_dns_packet_new_response(mtu); + + if (copy_queries) { + guint n, saved_rindex; + + saved_rindex = p->rindex; + p->rindex = AVAHI_DNS_PACKET_HEADER_SIZE; + + for (n = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_QDCOUNT); n > 0; n--) { + AvahiKey *k; + gboolean unicast_response; + + if ((k = avahi_dns_packet_consume_key(p, &unicast_response))) { + avahi_dns_packet_append_key(r, k, unicast_response); + avahi_key_unref(k); + } + } + + p->rindex = saved_rindex; + + avahi_dns_packet_set_field(r, AVAHI_DNS_FIELD_QDCOUNT, avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_QDCOUNT)); + } + + avahi_dns_packet_set_field(r, AVAHI_DNS_FIELD_ID, avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ID)); + + avahi_dns_packet_set_field(r, AVAHI_DNS_FIELD_FLAGS, + (avahi_dns_packet_get_field(r, AVAHI_DNS_FIELD_FLAGS) & ~AVAHI_DNS_FLAG_OPCODE) | + (avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_FLAGS) & AVAHI_DNS_FLAG_OPCODE) | + (aa ? AVAHI_DNS_FLAG_AA : 0)); + + return r; +} + + void avahi_dns_packet_free(AvahiDnsPacket *p) { g_assert(p); @@ -654,7 +698,7 @@ guint8* avahi_dns_packet_append_key(AvahiDnsPacket *p, AvahiKey *k, gboolean uni return t; } -guint8* avahi_dns_packet_append_record(AvahiDnsPacket *p, AvahiRecord *r, gboolean cache_flush) { +guint8* avahi_dns_packet_append_record(AvahiDnsPacket *p, AvahiRecord *r, gboolean cache_flush, guint max_ttl) { guint8 *t, *l, *start; guint size; @@ -666,7 +710,7 @@ guint8* avahi_dns_packet_append_record(AvahiDnsPacket *p, AvahiRecord *r, gboole if (!(t = avahi_dns_packet_append_name(p, r->key->name)) || !avahi_dns_packet_append_uint16(p, r->key->type) || !avahi_dns_packet_append_uint16(p, cache_flush ? (r->key->class | AVAHI_DNS_CACHE_FLUSH) : (r->key->class &~ AVAHI_DNS_CACHE_FLUSH)) || - !avahi_dns_packet_append_uint32(p, r->ttl) || + !avahi_dns_packet_append_uint32(p, (max_ttl && r->ttl > max_ttl) ? max_ttl : r->ttl) || !(l = avahi_dns_packet_append_uint16(p, 0))) goto fail; diff --git a/avahi-core/dns.h b/avahi-core/dns.h index 7936bae..c7d858f 100644 --- a/avahi-core/dns.h +++ b/avahi-core/dns.h @@ -37,9 +37,11 @@ typedef struct AvahiDnsPacket { #define AVAHI_DNS_PACKET_DATA(p) (((guint8*) p) + sizeof(AvahiDnsPacket)) -AvahiDnsPacket* avahi_dns_packet_new(guint size); -AvahiDnsPacket* avahi_dns_packet_new_query(guint size); -AvahiDnsPacket* avahi_dns_packet_new_response(guint size); +AvahiDnsPacket* avahi_dns_packet_new(guint mtu); +AvahiDnsPacket* avahi_dns_packet_new_query(guint mtu); +AvahiDnsPacket* avahi_dns_packet_new_response(guint mtu); + +AvahiDnsPacket* avahi_dns_packet_new_reply(AvahiDnsPacket* p, guint mtu, gboolean copy_queries, gboolean aa); void avahi_dns_packet_free(AvahiDnsPacket *p); void avahi_dns_packet_set_field(AvahiDnsPacket *p, guint index, guint16 v); @@ -52,7 +54,7 @@ guint8 *avahi_dns_packet_append_uint32(AvahiDnsPacket *p, guint32 v); guint8 *avahi_dns_packet_append_name(AvahiDnsPacket *p, const gchar *name); guint8 *avahi_dns_packet_append_bytes(AvahiDnsPacket *p, gconstpointer, guint l); guint8* avahi_dns_packet_append_key(AvahiDnsPacket *p, AvahiKey *k, gboolean unicast_response); -guint8* avahi_dns_packet_append_record(AvahiDnsPacket *p, AvahiRecord *r, gboolean cache_flush); +guint8* avahi_dns_packet_append_record(AvahiDnsPacket *p, AvahiRecord *r, gboolean cache_flush, guint max_ttl); guint8* avahi_dns_packet_append_string(AvahiDnsPacket *p, const gchar *s); gint avahi_dns_packet_is_query(AvahiDnsPacket *p); @@ -84,6 +86,7 @@ guint avahi_dns_packet_space(AvahiDnsPacket *p); #define AVAHI_DNS_FLAG_OPCODE (15 << 11) #define AVAHI_DNS_FLAG_RCODE (15) #define AVAHI_DNS_FLAG_TC (1 << 9) +#define AVAHI_DNS_FLAG_AA (1 << 10) #define AVAHI_DNS_FLAGS(qr, opcode, aa, tc, rd, ra, z, ad, cd, rcode) \ (((guint16) !!qr << 15) | \ diff --git a/avahi-core/iface.c b/avahi-core/iface.c index 13ffcef..9ac4493 100644 --- a/avahi-core/iface.c +++ b/avahi-core/iface.c @@ -472,43 +472,62 @@ AvahiHwInterface* avahi_interface_monitor_get_hw_interface(AvahiInterfaceMonitor } -void avahi_interface_send_packet(AvahiInterface *i, AvahiDnsPacket *p) { +void avahi_interface_send_packet_unicast(AvahiInterface *i, AvahiDnsPacket *p, const AvahiAddress *a, guint16 port) { g_assert(i); g_assert(p); + char t[64]; - if (avahi_interface_relevant(i)) { - g_message("sending on '%s.%i'", i->hardware->name, i->protocol); + if (!avahi_interface_relevant(i)) + return; + + g_assert(!a || a->family == i->protocol); - if (i->protocol == AF_INET && i->monitor->server->fd_ipv4 >= 0) - avahi_send_dns_packet_ipv4(i->monitor->server->fd_ipv4, i->hardware->index, p); - else if (i->protocol == AF_INET6 && i->monitor->server->fd_ipv6 >= 0) - avahi_send_dns_packet_ipv6(i->monitor->server->fd_ipv6, i->hardware->index, p); - } + if (a) + g_message("unicast sending on '%s.%i' to %s:%u", i->hardware->name, i->protocol, avahi_address_snprint(t, sizeof(t), a), port); + else + g_message("multicast sending on '%s.%i'", i->hardware->name, i->protocol); + + if (i->protocol == AF_INET && i->monitor->server->fd_ipv4 >= 0) + avahi_send_dns_packet_ipv4(i->monitor->server->fd_ipv4, i->hardware->index, p, a ? &a->data.ipv4 : NULL, port); + else if (i->protocol == AF_INET6 && i->monitor->server->fd_ipv6 >= 0) + avahi_send_dns_packet_ipv6(i->monitor->server->fd_ipv6, i->hardware->index, p, a ? &a->data.ipv6 : NULL, port); +} + +void avahi_interface_send_packet(AvahiInterface *i, AvahiDnsPacket *p) { + g_assert(i); + g_assert(p); + + avahi_interface_send_packet_unicast(i, p, NULL, 0); } -void avahi_interface_post_query(AvahiInterface *i, AvahiKey *key, gboolean immediately) { +gboolean avahi_interface_post_query(AvahiInterface *i, AvahiKey *key, gboolean immediately) { g_assert(i); g_assert(key); if (avahi_interface_relevant(i)) - avahi_packet_scheduler_post_query(i->scheduler, key, immediately); -} + return avahi_packet_scheduler_post_query(i->scheduler, key, immediately); + return FALSE; +} -void avahi_interface_post_response(AvahiInterface *i, const AvahiAddress *a, AvahiRecord *record, gboolean flush_cache, gboolean immediately) { +gboolean avahi_interface_post_response(AvahiInterface *i, const AvahiAddress *a, AvahiRecord *record, gboolean flush_cache, gboolean immediately) { g_assert(i); g_assert(record); if (avahi_interface_relevant(i)) - avahi_packet_scheduler_post_response(i->scheduler, a, record, flush_cache, immediately); + return avahi_packet_scheduler_post_response(i->scheduler, a, record, flush_cache, immediately); + + return FALSE; } -void avahi_interface_post_probe(AvahiInterface *i, AvahiRecord *record, gboolean immediately) { +gboolean avahi_interface_post_probe(AvahiInterface *i, AvahiRecord *record, gboolean immediately) { g_assert(i); g_assert(record); if (avahi_interface_relevant(i)) - avahi_packet_scheduler_post_probe(i->scheduler, record, immediately); + return avahi_packet_scheduler_post_probe(i->scheduler, record, immediately); + + return FALSE; } void avahi_dump_caches(AvahiInterfaceMonitor *m, FILE *f) { diff --git a/avahi-core/iface.h b/avahi-core/iface.h index bedf331..431dae3 100644 --- a/avahi-core/iface.h +++ b/avahi-core/iface.h @@ -104,10 +104,11 @@ AvahiInterface* avahi_interface_monitor_get_interface(AvahiInterfaceMonitor *m, AvahiHwInterface* avahi_interface_monitor_get_hw_interface(AvahiInterfaceMonitor *m, gint index); void avahi_interface_send_packet(AvahiInterface *i, AvahiDnsPacket *p); +void avahi_interface_send_packet_unicast(AvahiInterface *i, AvahiDnsPacket *p, const AvahiAddress *a, guint16 port); -void avahi_interface_post_query(AvahiInterface *i, AvahiKey *k, gboolean immediately); -void avahi_interface_post_probe(AvahiInterface *i, AvahiRecord *p, gboolean immediately); -void avahi_interface_post_response(AvahiInterface *i, const AvahiAddress *a, AvahiRecord *record, gboolean flush_cache, gboolean immediately); +gboolean avahi_interface_post_query(AvahiInterface *i, AvahiKey *k, gboolean immediately); +gboolean avahi_interface_post_probe(AvahiInterface *i, AvahiRecord *p, gboolean immediately); +gboolean avahi_interface_post_response(AvahiInterface *i, const AvahiAddress *a, AvahiRecord *record, gboolean flush_cache, gboolean immediately); void avahi_dump_caches(AvahiInterfaceMonitor *m, FILE *f); diff --git a/avahi-core/psched.c b/avahi-core/psched.c index 249e279..5af4a07 100644 --- a/avahi-core/psched.c +++ b/avahi-core/psched.c @@ -163,7 +163,7 @@ static void append_known_answers_and_send(AvahiPacketScheduler *s, AvahiDnsPacke while ((ka = s->known_answers)) { - while (!avahi_dns_packet_append_record(p, ka->record, FALSE)) { + while (!avahi_dns_packet_append_record(p, ka->record, FALSE, 0)) { g_assert(!avahi_dns_packet_is_empty(p)); @@ -172,7 +172,7 @@ static void append_known_answers_and_send(AvahiPacketScheduler *s, AvahiDnsPacke avahi_interface_send_packet(s->interface, p); avahi_dns_packet_free(p); - p = avahi_dns_packet_new_query(s->interface->hardware->mtu - 48); + p = avahi_dns_packet_new_query(s->interface->hardware->mtu); n = 0; } @@ -206,7 +206,7 @@ static void query_elapse(AvahiTimeEvent *e, gpointer data) { g_assert(!s->known_answers); - p = avahi_dns_packet_new_query(s->interface->hardware->mtu - 48); + p = avahi_dns_packet_new_query(s->interface->hardware->mtu); d = packet_add_query_job(s, p, qj); g_assert(d); n = 1; @@ -246,7 +246,7 @@ AvahiQueryJob* query_job_new(AvahiPacketScheduler *s, AvahiKey *key) { return qj; } -void avahi_packet_scheduler_post_query(AvahiPacketScheduler *s, AvahiKey *key, gboolean immediately) { +gboolean avahi_packet_scheduler_post_query(AvahiPacketScheduler *s, AvahiKey *key, gboolean immediately) { GTimeVal tv; AvahiQueryJob *qj; @@ -264,7 +264,7 @@ void avahi_packet_scheduler_post_query(AvahiPacketScheduler *s, AvahiKey *key, g /* Duplicate questions suppression */ if (d >= 0 && d <= AVAHI_QUERY_HISTORY_MSEC*1000) { g_message("WARNING! DUPLICATE QUERY SUPPRESSION ACTIVE!"); - return; + return FALSE; } query_job_free(s, qj); @@ -276,6 +276,7 @@ void avahi_packet_scheduler_post_query(AvahiPacketScheduler *s, AvahiKey *key, g qj = query_job_new(s, key); qj->delivery = tv; qj->time_event = avahi_time_event_queue_add(s->server->time_event_queue, &qj->delivery, query_elapse, qj); + return TRUE; } static guint8* packet_add_response_job(AvahiPacketScheduler *s, AvahiDnsPacket *p, AvahiResponseJob *rj) { @@ -285,7 +286,7 @@ static guint8* packet_add_response_job(AvahiPacketScheduler *s, AvahiDnsPacket * g_assert(p); g_assert(rj); - if ((d = avahi_dns_packet_append_record(p, rj->record, rj->flush_cache))) { + if ((d = avahi_dns_packet_append_record(p, rj->record, rj->flush_cache, 0))) { GTimeVal tv; rj->done = 1; @@ -306,7 +307,7 @@ static void send_response_packet(AvahiPacketScheduler *s, AvahiResponseJob *rj) g_assert(s); - p = avahi_dns_packet_new_response(s->interface->hardware->mtu - 200); + p = avahi_dns_packet_new_response(s->interface->hardware->mtu); n = 0; /* If a job was specified, put it in the packet. */ @@ -382,7 +383,7 @@ static AvahiResponseJob* response_job_new(AvahiPacketScheduler *s, AvahiRecord * return rj; } -void avahi_packet_scheduler_post_response(AvahiPacketScheduler *s, const AvahiAddress *a, AvahiRecord *record, gboolean flush_cache, gboolean immediately) { +gboolean avahi_packet_scheduler_post_response(AvahiPacketScheduler *s, const AvahiAddress *a, AvahiRecord *record, gboolean flush_cache, gboolean immediately) { AvahiResponseJob *rj; GTimeVal tv; @@ -415,7 +416,7 @@ void avahi_packet_scheduler_post_response(AvahiPacketScheduler *s, const AvahiAd rj->flush_cache = flush_cache; - return; + return FALSE; } /* Either one was a goodbye packet, but the other was not, so @@ -438,6 +439,8 @@ void avahi_packet_scheduler_post_response(AvahiPacketScheduler *s, const AvahiAd if ((rj->address_valid = !!a)) rj->address = *a; + + return TRUE; } void avahi_packet_scheduler_incoming_query(AvahiPacketScheduler *s, AvahiKey *key) { @@ -663,7 +666,7 @@ static void probe_elapse(AvahiTimeEvent *e, gpointer data) { g_assert(pj); s = pj->scheduler; - p = avahi_dns_packet_new_query(s->interface->hardware->mtu - 48); + p = avahi_dns_packet_new_query(s->interface->hardware->mtu); /* Add the import probe */ if (!packet_add_probe_query(s, p, pj)) { @@ -698,7 +701,7 @@ static void probe_elapse(AvahiTimeEvent *e, gpointer data) { if (!pj->chosen) continue; - if (!avahi_dns_packet_append_record(p, pj->record, TRUE)) { + if (!avahi_dns_packet_append_record(p, pj->record, TRUE, 0)) { g_warning("Bad probe size estimate!"); /* Unmark all following jobs */ @@ -720,7 +723,7 @@ static void probe_elapse(AvahiTimeEvent *e, gpointer data) { avahi_dns_packet_free(p); } -void avahi_packet_scheduler_post_probe(AvahiPacketScheduler *s, AvahiRecord *record, gboolean immediately) { +gboolean avahi_packet_scheduler_post_probe(AvahiPacketScheduler *s, AvahiRecord *record, gboolean immediately) { AvahiProbeJob *pj; GTimeVal tv; @@ -734,4 +737,6 @@ void avahi_packet_scheduler_post_probe(AvahiPacketScheduler *s, AvahiRecord *rec pj = probe_job_new(s, record); pj->delivery = tv; pj->time_event = avahi_time_event_queue_add(s->server->time_event_queue, &pj->delivery, probe_elapse, pj); + + return TRUE; } diff --git a/avahi-core/psched.h b/avahi-core/psched.h index fe621ca..b31b45e 100644 --- a/avahi-core/psched.h +++ b/avahi-core/psched.h @@ -86,9 +86,9 @@ struct AvahiPacketScheduler { AvahiPacketScheduler *avahi_packet_scheduler_new(AvahiServer *server, AvahiInterface *i); void avahi_packet_scheduler_free(AvahiPacketScheduler *s); -void avahi_packet_scheduler_post_query(AvahiPacketScheduler *s, AvahiKey *key, gboolean immediately); -void avahi_packet_scheduler_post_response(AvahiPacketScheduler *s, const AvahiAddress *a, AvahiRecord *record, gboolean flush_cache, gboolean immediately); -void avahi_packet_scheduler_post_probe(AvahiPacketScheduler *s, AvahiRecord *record, gboolean immediately); +gboolean avahi_packet_scheduler_post_query(AvahiPacketScheduler *s, AvahiKey *key, gboolean immediately); +gboolean avahi_packet_scheduler_post_response(AvahiPacketScheduler *s, const AvahiAddress *a, AvahiRecord *record, gboolean flush_cache, gboolean immediately); +gboolean avahi_packet_scheduler_post_probe(AvahiPacketScheduler *s, AvahiRecord *record, gboolean immediately); void avahi_packet_scheduler_incoming_query(AvahiPacketScheduler *s, AvahiKey *key); void avahi_packet_scheduler_incoming_response(AvahiPacketScheduler *s, AvahiRecord *record); diff --git a/avahi-core/server.c b/avahi-core/server.c index 033622d..3f37e1f 100644 --- a/avahi-core/server.c +++ b/avahi-core/server.c @@ -102,7 +102,83 @@ static void cleanup_dead(AvahiServer *s) { } } -static void handle_query_key(AvahiServer *s, AvahiKey *k, AvahiInterface *i, const AvahiAddress *a, guint16 port, gboolean legacy_unicast, gboolean unicast_response) { +static void send_unicast_response_packet(AvahiServer *s, AvahiInterface *i, const AvahiAddress *a, guint16 port) { + g_assert(s); + g_assert(a); + g_assert(port > 0); + g_assert(s->unicast_packet); + + if (avahi_dns_packet_get_field(s->unicast_packet, AVAHI_DNS_FIELD_ANCOUNT) != 0) + avahi_interface_send_packet_unicast(i, s->unicast_packet, a, port); + + avahi_dns_packet_free(s->unicast_packet); + s->unicast_packet = NULL; +} + +static void post_response(AvahiServer *s, AvahiDnsPacket *p, AvahiInterface *i, const AvahiAddress *a, guint16 port, AvahiRecord *r, gboolean flush_cache, gboolean legacy_unicast, gboolean unicast_response) { + g_assert(s); + g_assert(a); + g_assert(port > 0); + g_assert(r); + + if (legacy_unicast) { + + /* Respond with a legacy unicast packet */ + + if (!(s->unicast_packet)) + s->unicast_packet = avahi_dns_packet_new_reply(p, 512 /* unicast DNS maximum packet size is 512 */ , TRUE, TRUE); + + if (avahi_dns_packet_append_record(s->unicast_packet, r, FALSE, 10)) + + /* Increment the ANCOUNT field */ + + avahi_dns_packet_set_field(s->unicast_packet, AVAHI_DNS_FIELD_ANCOUNT, + avahi_dns_packet_get_field(s->unicast_packet, AVAHI_DNS_FIELD_ANCOUNT)+1); + + /* If there's no space left for this response we simply don't send it */ + + } else { + + if (!avahi_interface_post_response(i, a, r, flush_cache, FALSE) && unicast_response) { + + /* Due to some reasons the record has not been scheduled. + * The client requested an unicast response in that + * case. Therefore we prepare such a response */ + + for (;;) { + + if (!(s->unicast_packet)) + s->unicast_packet = avahi_dns_packet_new_reply(p, i->hardware->mtu, FALSE, FALSE); + + if (avahi_dns_packet_append_record(s->unicast_packet, r, flush_cache, 0)) { + + /* Appending this record succeeded, so incremeant + * the specific header field, and return to the caller */ + + avahi_dns_packet_set_field(s->unicast_packet, AVAHI_DNS_FIELD_ANCOUNT, + avahi_dns_packet_get_field(s->unicast_packet, AVAHI_DNS_FIELD_ANCOUNT)+1); + + break; + } + + if (avahi_dns_packet_get_field(s->unicast_packet, AVAHI_DNS_FIELD_ANCOUNT) == 0) { + g_warning("Record too large, doesn't fit in any packet!"); + return; + } + + /* Appending the record didn't succeeed, so let's send this packet, and create a new one */ + + send_unicast_response_packet(s, i, a, port); + + avahi_dns_packet_free(s->unicast_packet); + s->unicast_packet = NULL; + } + + } + } +} + +static void handle_query_key(AvahiServer *s, AvahiDnsPacket *p, AvahiKey *k, AvahiInterface *i, const AvahiAddress *a, guint16 port, gboolean legacy_unicast, gboolean unicast_response) { AvahiEntry *e; gchar *txt; @@ -122,14 +198,15 @@ static void handle_query_key(AvahiServer *s, AvahiKey *k, AvahiInterface *i, con for (e = s->entries; e; e = e->entries_next) if (!e->dead && avahi_key_pattern_match(k, e->record->key) && avahi_entry_registered(s, e, i)) - avahi_interface_post_response(i, a, e->record, e->flags & AVAHI_ENTRY_UNIQUE, FALSE); + post_response(s, p, i, a, port, e->record, e->flags & AVAHI_ENTRY_UNIQUE, legacy_unicast, unicast_response); + } else { /* Handle all other queries */ for (e = g_hash_table_lookup(s->entries_by_key, k); e; e = e->by_key_next) if (!e->dead && avahi_entry_registered(s, e, i)) - avahi_interface_post_response(i, a, e->record, e->flags & AVAHI_ENTRY_UNIQUE, FALSE); + post_response(s, p, i, a, port, e->record, e->flags & AVAHI_ENTRY_UNIQUE, legacy_unicast, unicast_response); } } @@ -196,6 +273,8 @@ static void handle_query(AvahiServer *s, AvahiDnsPacket *p, AvahiInterface *i, c g_assert(i); g_assert(a); + g_assert(!s->unicast_packet); + /* Handle the questions */ for (n = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_QDCOUNT); n > 0; n --) { AvahiKey *key; @@ -206,7 +285,7 @@ static void handle_query(AvahiServer *s, AvahiDnsPacket *p, AvahiInterface *i, c return; } - handle_query_key(s, key, i, a, port, legacy_unicast, unicast_response); + handle_query_key(s, p, key, i, a, port, legacy_unicast, unicast_response); avahi_key_unref(key); } @@ -239,6 +318,9 @@ static void handle_query(AvahiServer *s, AvahiDnsPacket *p, AvahiInterface *i, c avahi_record_unref(record); } + + if (s->unicast_packet) + send_unicast_response_packet(s, i, a, port); } static gboolean handle_conflict(AvahiServer *s, AvahiInterface *i, AvahiRecord *record, gboolean unique, const AvahiAddress *a) { @@ -557,6 +639,8 @@ AvahiServer *avahi_server_new(GMainContext *c) { s->hostname = g_strdup_printf("%s.local.", hn); g_free(hn); + s->unicast_packet = NULL; + s->time_event_queue = avahi_time_event_queue_new(s->context, G_PRIORITY_DEFAULT+10); /* Slightly less priority than the FDs */ s->monitor = avahi_interface_monitor_new(s); avahi_interface_monitor_sync(s->monitor); @@ -611,6 +695,9 @@ void avahi_server_free(AvahiServer* s) { g_source_unref(s->source); g_main_context_unref(s->context); + if (s->unicast_packet) + avahi_dns_packet_free(s->unicast_packet); + g_free(s); } diff --git a/avahi-core/server.h b/avahi-core/server.h index 6767884..226672f 100644 --- a/avahi-core/server.h +++ b/avahi-core/server.h @@ -29,6 +29,7 @@ #include "timeeventq.h" #include "announce.h" #include "subscribe.h" +#include "dns.h" struct AvahiEntry { AvahiServer *server; @@ -86,6 +87,8 @@ struct AvahiServer { GSource *source; gboolean ignore_bad_ttl; + + AvahiDnsPacket *unicast_packet; }; gboolean avahi_server_entry_match_interface(AvahiEntry *e, AvahiInterface *i); diff --git a/avahi-core/socket.c b/avahi-core/socket.c index e59c78a..86e2a6f 100644 --- a/avahi-core/socket.c +++ b/avahi-core/socket.c @@ -61,8 +61,29 @@ static void mdns_mcast_group_ipv6(struct sockaddr_in6 *ret_sa) { inet_pton(AF_INET6, "ff02::fb", &ret_sa->sin6_addr); } -int avahi_mdns_mcast_join_ipv4 (int index, int fd) -{ +static void ipv4_address_to_sockaddr(struct sockaddr_in *ret_sa, const AvahiIPv4Address *a, guint16 port) { + g_assert(ret_sa); + g_assert(a); + g_assert(port > 0); + + memset(ret_sa, 0, sizeof(struct sockaddr_in)); + ret_sa->sin_family = AF_INET; + ret_sa->sin_port = htons(port); + memcpy(&ret_sa->sin_addr, a, sizeof(AvahiIPv4Address)); +} + +static void ipv6_address_to_sockaddr(struct sockaddr_in6 *ret_sa, const AvahiIPv6Address *a, guint16 port) { + g_assert(ret_sa); + g_assert(a); + g_assert(port > 0); + + memset(ret_sa, 0, sizeof(struct sockaddr_in6)); + ret_sa->sin6_family = AF_INET6; + ret_sa->sin6_port = htons(port); + memcpy(&ret_sa->sin6_addr, a, sizeof(AvahiIPv6Address)); +} + +int avahi_mdns_mcast_join_ipv4 (int index, int fd) { struct ip_mreqn mreq; struct sockaddr_in sa; @@ -80,8 +101,7 @@ int avahi_mdns_mcast_join_ipv4 (int index, int fd) return 0; } -int avahi_mdns_mcast_join_ipv6 (int index, int fd) -{ +int avahi_mdns_mcast_join_ipv6 (int index, int fd) { struct ipv6_mreq mreq6; struct sockaddr_in6 sa6; @@ -99,8 +119,7 @@ int avahi_mdns_mcast_join_ipv6 (int index, int fd) return 0; } -int avahi_mdns_mcast_leave_ipv4 (int index, int fd) -{ +int avahi_mdns_mcast_leave_ipv4 (int index, int fd) { struct ip_mreqn mreq; struct sockaddr_in sa; @@ -118,8 +137,7 @@ int avahi_mdns_mcast_leave_ipv4 (int index, int fd) return 0; } -int avahi_mdns_mcast_leave_ipv6 (int index, int fd) -{ +int avahi_mdns_mcast_leave_ipv6 (int index, int fd) { struct ipv6_mreq mreq6; struct sockaddr_in6 sa6; @@ -313,7 +331,7 @@ static gint sendmsg_loop(gint fd, struct msghdr *msg, gint flags) { return 0; } -gint avahi_send_dns_packet_ipv4(gint fd, gint interface, AvahiDnsPacket *p) { +gint avahi_send_dns_packet_ipv4(gint fd, gint interface, AvahiDnsPacket *p, const AvahiIPv4Address *a, guint16 port) { struct sockaddr_in sa; struct msghdr msg; struct iovec io; @@ -324,8 +342,12 @@ gint avahi_send_dns_packet_ipv4(gint fd, gint interface, AvahiDnsPacket *p) { g_assert(fd >= 0); g_assert(p); g_assert(avahi_dns_packet_check_valid(p) >= 0); + g_assert(!a || port > 0); - mdns_mcast_group_ipv4(&sa); + if (!a) + mdns_mcast_group_ipv4(&sa); + else + ipv4_address_to_sockaddr(&sa, a, port); memset(&io, 0, sizeof(io)); io.iov_base = AVAHI_DNS_PACKET_DATA(p); @@ -352,7 +374,7 @@ gint avahi_send_dns_packet_ipv4(gint fd, gint interface, AvahiDnsPacket *p) { return sendmsg_loop(fd, &msg, MSG_DONTROUTE); } -gint avahi_send_dns_packet_ipv6(gint fd, gint interface, AvahiDnsPacket *p) { +gint avahi_send_dns_packet_ipv6(gint fd, gint interface, AvahiDnsPacket *p, const AvahiIPv6Address *a, guint16 port) { struct sockaddr_in6 sa; struct msghdr msg; struct iovec io; @@ -364,7 +386,10 @@ gint avahi_send_dns_packet_ipv6(gint fd, gint interface, AvahiDnsPacket *p) { g_assert(p); g_assert(avahi_dns_packet_check_valid(p) >= 0); - mdns_mcast_group_ipv6(&sa); + if (!a) + mdns_mcast_group_ipv6(&sa); + else + ipv6_address_to_sockaddr(&sa, a, port); memset(&io, 0, sizeof(io)); io.iov_base = AVAHI_DNS_PACKET_DATA(p); diff --git a/avahi-core/socket.h b/avahi-core/socket.h index 4f6c5a3..fe41254 100644 --- a/avahi-core/socket.h +++ b/avahi-core/socket.h @@ -31,8 +31,8 @@ gint avahi_open_socket_ipv4(void); gint avahi_open_socket_ipv6(void); -gint avahi_send_dns_packet_ipv4(gint fd, gint iface, AvahiDnsPacket *p); -gint avahi_send_dns_packet_ipv6(gint fd, gint iface, AvahiDnsPacket *p); +gint avahi_send_dns_packet_ipv4(gint fd, gint iface, AvahiDnsPacket *p, const AvahiIPv4Address *a, guint16 port); +gint avahi_send_dns_packet_ipv6(gint fd, gint iface, AvahiDnsPacket *p, const AvahiIPv6Address *a, guint16 port); AvahiDnsPacket *avahi_recv_dns_packet_ipv4(gint fd, struct sockaddr_in*ret_sa, gint *ret_iface, guint8 *ret_ttl); AvahiDnsPacket *avahi_recv_dns_packet_ipv6(gint fd, struct sockaddr_in6*ret_sa, gint *ret_iface, guint8 *ret_ttl); diff --git a/todo b/todo index 8019211..b0a9fef 100644 --- a/todo +++ b/todo @@ -1,7 +1,4 @@ todo: -* Unicast responses/queries -* Legacy unicast - * add SRV and TXT records referenced from PTR records automatically to packet * add A and AAAA records referenced from SRV records automatically to packet @@ -25,3 +22,5 @@ done: * allow NULL bytes in TXT records * add flx_server_add_service_strlst() and friends * change flx_* to avahi_* +* Unicast responses/queries +* Legacy unicast -- 2.39.2