@ -46,23 +46,20 @@
static void timeadd ( ares_timeval_t * now , size_t millisecs ) ; static void timeadd ( ares_timeval_t * now , size_t millisecs ) ;
static void write_tcp_data ( ares_channel_t * channel , fd_set * write_fds , static void process_ write( ares_channel_t * channel , fd_set * write_fds ,
ares_socket_t write_fd ) ; ares_socket_t write_fd ) ;
static void read_packets ( ares_channel_t * channel , fd_set * read_fds , static void process_read ( ares_channel_t * channel , fd_set * read_fds ,
ares_socket_t read_fd , const ares_timeval_t * now ) ; ares_socket_t read_fd , const ares_timeval_t * now ) ;
static void process_timeouts ( ares_channel_t * channel , static void process_timeouts ( ares_channel_t * channel ,
const ares_timeval_t * now ) ; const ares_timeval_t * now ) ;
static ares_status_t process_answer ( ares_channel_t * channel , static ares_status_t process_answer ( ares_channel_t * channel ,
const unsigned char * abuf , size_t alen , const unsigned char * abuf , size_t alen ,
ares_conn_t * conn , ares_bool_t tcp , ares_conn_t * conn ,
const ares_timeval_t * now ) ; const ares_timeval_t * now ) ;
static void handle_conn_error ( ares_conn_t * conn , ares_bool_t critical_failure , static void handle_conn_error ( ares_conn_t * conn , ares_bool_t critical_failure ,
ares_status_t failure_status ) ; ares_status_t failure_status ) ;
static ares_bool_t same_questions ( const ares_query_t * query , static ares_bool_t same_questions ( const ares_query_t * query ,
const ares_dns_record_t * arec ) ; const ares_dns_record_t * arec ) ;
static ares_bool_t same_address ( const struct sockaddr * sa ,
const struct ares_addr * aa ) ;
static void end_query ( ares_channel_t * channel , ares_server_t * server , static void end_query ( ares_channel_t * channel , ares_server_t * server ,
ares_query_t * query , ares_status_t status , ares_query_t * query , ares_status_t status ,
const ares_dns_record_t * dnsrec ) ; const ares_dns_record_t * dnsrec ) ;
@ -204,12 +201,10 @@ static void processfds(ares_channel_t *channel, fd_set *read_fds,
} }
ares__channel_lock ( channel ) ; ares__channel_lock ( channel ) ;
ares__tvnow ( & now ) ; ares__tvnow ( & now ) ;
read_packets ( channel , read_fds , read_fd , & now ) ; process_read ( channel , read_fds , read_fd , & now ) ;
process_timeouts ( channel , & now ) ; process_timeouts ( channel , & now ) ;
/* Write last as the other 2 operations might have triggered writes */ process_write ( channel , write_fds , write_fd ) ;
write_tcp_data ( channel , write_fds , write_fd ) ;
/* See if any connections should be cleaned up */ /* See if any connections should be cleaned up */
ares__check_cleanup_conns ( channel ) ; ares__check_cleanup_conns ( channel ) ;
@ -235,105 +230,233 @@ void ares_process_fd(ares_channel_t *channel,
processfds ( channel , NULL , read_fd , NULL , write_fd ) ; processfds ( channel , NULL , read_fd , NULL , write_fd ) ;
} }
static ares_socket_t * channel_socket_list ( const ares_channel_t * channel ,
size_t * num )
{
ares__slist_node_t * snode ;
ares__array_t * arr = ares__array_create ( sizeof ( ares_socket_t ) , NULL ) ;
* num = 0 ;
if ( arr = = NULL ) {
return NULL ; /* LCOV_EXCL_LINE: OutOfMemory */
}
for ( snode = ares__slist_node_first ( channel - > servers ) ; snode ! = NULL ;
snode = ares__slist_node_next ( snode ) ) {
ares_server_t * server = ares__slist_node_val ( snode ) ;
ares__llist_node_t * node ;
for ( node = ares__llist_node_first ( server - > connections ) ; node ! = NULL ;
node = ares__llist_node_next ( node ) ) {
const ares_conn_t * conn = ares__llist_node_val ( node ) ;
ares_socket_t * sptr ;
ares_status_t status ;
if ( conn - > fd = = ARES_SOCKET_BAD ) {
continue ;
}
status = ares__array_insert_last ( ( void * * ) & sptr , arr ) ;
if ( status ! = ARES_SUCCESS ) {
ares__array_destroy ( arr ) ; /* LCOV_EXCL_LINE: OutOfMemory */
return NULL ; /* LCOV_EXCL_LINE: OutOfMemory */
}
* sptr = conn - > fd ;
}
}
return ares__array_finish ( arr , num ) ;
}
/* If any TCP sockets select true for writing, write out queued data
/* If any TCP sockets select true for writing, write out queued data
* we have for them . * we have for them .
*/ */
static void write_tcp_data ( ares_channel_t * channel , fd_set * write_fds , static void ares_notify_write ( ares_conn_t * conn )
ares_socket_t write_fd )
{ {
ares__slist_node_t * node ; ares_status_t status ;
/* Mark as connected if we got here and TFO Initial not set */
if ( ! ( conn - > flags & ARES_CONN_FLAG_TFO_INITIAL ) ) {
conn - > state_flags | = ARES_CONN_STATE_CONNECTED ;
}
status = ares__conn_flush ( conn ) ;
if ( status ! = ARES_SUCCESS ) {
handle_conn_error ( conn , ARES_TRUE , status ) ;
}
}
if ( ! write_fds & & ( write_fd = = ARES_SOCKET_BAD ) ) { static void process_write ( ares_channel_t * channel , fd_set * write_fds ,
ares_socket_t write_fd )
{
size_t i ;
ares_socket_t * socketlist = NULL ;
size_t num_sockets = 0 ;
ares__llist_node_t * node = NULL ;
if ( ! write_fds & & write_fd = = ARES_SOCKET_BAD ) {
/* no possible action */ /* no possible action */
return ; return ;
} }
for ( node = ares__slist_node_first ( channel - > servers ) ; node ! = NULL ; /* Single socket specified */
node = ares__slist_node_next ( node ) ) { if ( ! write_fds ) {
ares_server_t * server = ares__slist_node_val ( node ) ; node = ares__htable_asvp_get_direct ( channel - > connnode_by_socket , write_fd ) ;
const unsigned char * data ; if ( node = = NULL ) {
size_t data_len ; return ;
ares_ssize_t count ;
/* Make sure server has data to send and is selected in write_fds or
write_fd . */
if ( ares__buf_len ( server - > tcp_send ) = = 0 | | server - > tcp_conn = = NULL ) {
continue ;
} }
if ( write_fds ) { ares_notify_write ( ares__llist_node_val ( node ) ) ;
if ( ! FD_ISSET ( server - > tcp_conn - > fd , write_fds ) ) { return ;
continue ; }
}
} else {
if ( server - > tcp_conn - > fd ! = write_fd ) {
continue ;
}
}
if ( write_fds ) { /* There is no good way to iterate across an fd_set, instead we must pull a
/* If there's an error and we close this socket, then open
* list of all known fds , and iterate across that checking against the fd_set .
* another with the same fd to talk to another server , then we */
* don ' t want to think that it was the new socket that was socketlist = channel_socket_list ( channel , & num_sockets ) ;
* ready . This is not disastrous , but is likely to result in
* extra system calls and confusion . */
FD_CLR ( server - > tcp_conn - > fd , write_fds ) ;
}
data = ares__buf_peek ( server - > tcp_send , & data_len ) ; for ( i = 0 ; i < num_sockets ; i + + ) {
count = ares__conn_write ( server - > tcp_conn , data , data_len ) ; if ( ! FD_ISSET ( socketlist [ i ] , write_fds ) ) {
if ( count < = 0 ) {
if ( ! ares__socket_try_again ( SOCKERRNO ) ) {
handle_conn_error ( server - > tcp_conn , ARES_TRUE , ARES_ECONNREFUSED ) ;
}
continue ; continue ;
} }
/* Strip data written from the buffer */ /* If there's an error and we close this socket, then open
ares__buf_consume ( server - > tcp_send , ( size_t ) count ) ; * another with the same fd to talk to another server , then we
* don ' t want to think that it was the new socket that was
* ready . This is not disastrous , but is likely to result in
* extra system calls and confusion . */
FD_CLR ( socketlist [ i ] , write_fds ) ;
/* Notify state callback all data is written */ node =
if ( ares__buf_len ( server - > tcp_send ) = = 0 ) { ares__htable_asvp_get_direct ( channel - > connnode_by_socket , socketlist [ i ] ) ;
SOCK_STATE_CALLBACK ( channel , server - > tcp_conn - > fd , 1 , 0 ) ; if ( node = = NULL ) {
return ;
} }
ares_notify_write ( ares__llist_node_val ( node ) ) ;
} }
ares_free ( socketlist ) ;
} }
/* If any TCP socket selects true for reading, read some data,
void ares_process_pending_write ( ares_channel_t * channel )
* allocate a buffer if we finish reading the length word , and process
* a packet if we finish reading one .
*/
static void read_tcp_data ( ares_channel_t * channel , ares_conn_t * conn ,
const ares_timeval_t * now )
{ {
ares_ssize_t count ; ares__slist_node_t * node ;
ares_server_t * server = conn - > server ;
/* Fetch buffer to store data we are reading */ if ( channel = = NULL ) {
size_t ptr_len = 65535 ; return ;
unsigned char * ptr ; }
ares__channel_lock ( channel ) ;
if ( ! channel - > notify_pending_write ) {
ares__channel_unlock ( channel ) ;
return ;
}
ptr = ares__buf_append_start ( server - > tcp_parser , & ptr_len ) ; /* Set as untriggerd before calling into ares__conn_flush(), this is
* because its possible ares__conn_flush ( ) might cause additional data to
* be enqueued if there is some form of exception so it will need to recurse .
*/
channel - > notify_pending_write = ARES_FALSE ;
if ( ptr = = NULL ) { for ( node = ares__slist_node_first ( channel - > servers ) ; node ! = NULL ;
handle_conn_error ( conn , ARES_FALSE /* not critical to connection */ , node = ares__slist_node_next ( node ) ) {
ARES_SUCCESS ) ; ares_server_t * server = ares__slist_node_val ( node ) ;
return ; /* bail out on malloc failure. TODO: make this
ares_conn_t * conn = server - > tcp_conn ;
function return error codes */ ares_status_t status ;
if ( conn = = NULL ) {
continue ;
}
/* Enqueue any pending data if there is any */
status = ares__conn_flush ( conn ) ;
if ( status ! = ARES_SUCCESS ) {
handle_conn_error ( conn , ARES_TRUE , status ) ;
}
} }
/* Read from socket */ ares__channel_unlock ( channel ) ;
count = ares__socket_recv ( channel , conn - > fd , ptr , ptr_len ) ; }
if ( count < = 0 ) {
ares__buf_append_finish ( server - > tcp_parser , 0 ) ; static ares_status_t read_conn_packets ( ares_conn_t * conn )
if ( ! ( count = = - 1 & & ares__socket_try_again ( SOCKERRNO ) ) ) { {
handle_conn_error ( conn , ARES_TRUE , ARES_ECONNREFUSED ) ; ares_bool_t read_again ;
ares_conn_err_t err ;
ares_channel_t * channel = conn - > server - > channel ;
do {
size_t count ;
size_t len = 65535 ;
unsigned char * ptr ;
size_t start_len = ares__buf_len ( conn - > in_buf ) ;
/* If UDP, lets write out a placeholder for the length indicator */
if ( ! ( conn - > flags & ARES_CONN_FLAG_TCP ) ) {
if ( ares__buf_append_be16 ( conn - > in_buf , 0 ) ! = ARES_SUCCESS ) {
handle_conn_error ( conn , ARES_FALSE /* not critical to connection */ ,
ARES_SUCCESS ) ;
return ARES_ENOMEM ;
}
} }
return ;
/* Get a buffer of sufficient size */
ptr = ares__buf_append_start ( conn - > in_buf , & len ) ;
if ( ptr = = NULL ) {
handle_conn_error ( conn , ARES_FALSE /* not critical to connection */ ,
ARES_SUCCESS ) ;
return ARES_ENOMEM ;
}
/* Read from socket */
err = ares__conn_read ( conn , ptr , len , & count ) ;
if ( err ! = ARES_CONN_ERR_SUCCESS ) {
ares__buf_append_finish ( conn - > in_buf , 0 ) ;
if ( ! ( conn - > flags & ARES_CONN_FLAG_TCP ) ) {
ares__buf_set_length ( conn - > in_buf , start_len ) ;
}
break ;
}
/* Record amount of data read */
ares__buf_append_finish ( conn - > in_buf , ( size_t ) count ) ;
/* Only loop if we're not overwriting socket functions, and are using UDP
* or are using TCP and read the maximum buffer size */
read_again = ARES_FALSE ;
if ( channel - > sock_funcs = = NULL ) {
if ( ! ( conn - > flags & ARES_CONN_FLAG_TCP ) ) {
read_again = ARES_TRUE ;
} else if ( count = = len ) {
read_again = ARES_TRUE ;
}
}
/* If UDP, overwrite length */
if ( ! ( conn - > flags & ARES_CONN_FLAG_TCP ) ) {
len = ares__buf_len ( conn - > in_buf ) ;
ares__buf_set_length ( conn - > in_buf , start_len ) ;
ares__buf_append_be16 ( conn - > in_buf , ( unsigned short ) count ) ;
ares__buf_set_length ( conn - > in_buf , len ) ;
}
/* Try to read again only if *we* set up the socket, otherwise it may be
* a blocking socket and would cause recvfrom to hang . */
} while ( read_again ) ;
if ( err ! = ARES_CONN_ERR_SUCCESS & & err ! = ARES_CONN_ERR_WOULDBLOCK ) {
handle_conn_error ( conn , ARES_TRUE , ARES_ECONNREFUSED ) ;
return ARES_ECONNREFUSED ;
} }
/* Record amount of data read */ return ARES_SUCCESS ;
ares__buf_append_finish ( server - > tcp_parser , ( size_t ) count ) ; }
static void read_answers ( ares_conn_t * conn , const ares_timeval_t * now )
{
ares_channel_t * channel = conn - > server - > channel ;
/* Process all queued answers */ /* Process all queued answers */
while ( 1 ) { while ( 1 ) {
@ -343,24 +466,24 @@ static void read_tcp_data(ares_channel_t *channel, ares_conn_t *conn,
ares_status_t status ; ares_status_t status ;
/* Tag so we can roll back */ /* Tag so we can roll back */
ares__buf_tag ( server - > tcp_parser ) ; ares__buf_tag ( conn - > in_buf ) ;
/* Read length indicator */ /* Read length indicator */
if ( ares__buf_fetch_be16 ( server - > tcp_parser , & dns_len ) ! = ARES_SUCCESS ) { if ( ares__buf_fetch_be16 ( conn - > in_buf , & dns_len ) ! = ARES_SUCCESS ) {
ares__buf_tag_rollback ( server - > tcp_parser ) ; ares__buf_tag_rollback ( conn - > in_buf ) ;
break ; break ;
} }
/* Not enough data for a full response yet */ /* Not enough data for a full response yet */
if ( ares__buf_consume ( server - > tcp_parser , dns_len ) ! = ARES_SUCCESS ) { if ( ares__buf_consume ( conn - > in_buf , dns_len ) ! = ARES_SUCCESS ) {
ares__buf_tag_rollback ( server - > tcp_parser ) ; ares__buf_tag_rollback ( conn - > in_buf ) ;
break ; break ;
} }
/* Can't fail except for misuse */ /* Can't fail except for misuse */
data = ares__buf_tag_fetch ( server - > tcp_parser , & data_len ) ; data = ares__buf_tag_fetch ( conn - > in_buf , & data_len ) ;
if ( data = = NULL | | data_len < 2 ) { if ( data = = NULL | | data_len < 2 ) {
ares__buf_tag_clear ( server - > tcp_parser ) ; ares__buf_tag_clear ( conn - > in_buf ) ;
break ; break ;
} }
@ -369,126 +492,36 @@ static void read_tcp_data(ares_channel_t *channel, ares_conn_t *conn,
data_len - = 2 ; data_len - = 2 ;
/* We finished reading this answer; process it */ /* We finished reading this answer; process it */
status = process_answer ( channel , data , data_len , conn , ARES_TRUE , now ) ; status = process_answer ( channel , data , data_len , conn , now ) ;
if ( status ! = ARES_SUCCESS ) { if ( status ! = ARES_SUCCESS ) {
handle_conn_error ( conn , ARES_TRUE , status ) ; handle_conn_error ( conn , ARES_TRUE , status ) ;
return ; return ;
} }
/* Since we processed the answer, clear the tag so space can be reclaimed */ /* Since we processed the answer, clear the tag so space can be reclaimed */
ares__buf_tag_clear ( server - > tcp_parser ) ; ares__buf_tag_clear ( conn - > in_buf ) ;
} }
} }
static ares_socket_t * channel_socket_list ( const ares_channel_t * channel , static void read_conn ( ares_conn_t * conn , const ares_timeval_t * now )
size_t * num )
{ {
ares__slist_node_t * snode ; /* TODO: There might be a potential issue here where there was a read that
ares__array_t * arr = ares__array_create ( sizeof ( ares_socket_t ) , NULL ) ; * read some data , then looped and read again and got a disconnect .
* Right now , that would cause a resend instead of processing the data
* num = 0 ; * we have . This is fairly unlikely to occur due to only looping if
* a full buffer of 65535 bytes was read . */
if ( arr = = NULL ) { if ( read_conn_packets ( conn ) ! = ARES_SUCCESS ) {
return NULL ; /* LCOV_EXCL_LINE: OutOfMemory */ return ;
}
for ( snode = ares__slist_node_first ( channel - > servers ) ; snode ! = NULL ;
snode = ares__slist_node_next ( snode ) ) {
ares_server_t * server = ares__slist_node_val ( snode ) ;
ares__llist_node_t * node ;
for ( node = ares__llist_node_first ( server - > connections ) ; node ! = NULL ;
node = ares__llist_node_next ( node ) ) {
const ares_conn_t * conn = ares__llist_node_val ( node ) ;
ares_socket_t * sptr ;
ares_status_t status ;
if ( conn - > fd = = ARES_SOCKET_BAD ) {
continue ;
}
status = ares__array_insert_last ( ( void * * ) & sptr , arr ) ;
if ( status ! = ARES_SUCCESS ) {
ares__array_destroy ( arr ) ; /* LCOV_EXCL_LINE: OutOfMemory */
return NULL ; /* LCOV_EXCL_LINE: OutOfMemory */
}
* sptr = conn - > fd ;
}
} }
read_answers ( conn , now ) ;
return ares__array_finish ( arr , num ) ;
}
/* If any UDP sockets select true for reading, process them. */
static void read_udp_packets_fd ( ares_channel_t * channel , ares_conn_t * conn ,
const ares_timeval_t * now )
{
ares_ssize_t read_len ;
unsigned char buf [ MAXENDSSZ + 1 ] ;
# ifdef HAVE_RECVFROM
ares_socklen_t fromlen ;
union {
struct sockaddr sa ;
struct sockaddr_in sa4 ;
struct sockaddr_in6 sa6 ;
} from ;
memset ( & from , 0 , sizeof ( from ) ) ;
# endif
/* To reduce event loop overhead, read and process as many
* packets as we can . */
do {
if ( conn - > fd = = ARES_SOCKET_BAD ) {
read_len = - 1 ;
} else {
if ( conn - > server - > addr . family = = AF_INET ) {
fromlen = sizeof ( from . sa4 ) ;
} else {
fromlen = sizeof ( from . sa6 ) ;
}
read_len = ares__socket_recvfrom ( channel , conn - > fd , ( void * ) buf ,
sizeof ( buf ) , 0 , & from . sa , & fromlen ) ;
}
if ( read_len = = 0 ) {
/* UDP is connectionless, so result code of 0 is a 0-length UDP
* packet , and not an indication the connection is closed like on
* tcp */
continue ;
} else if ( read_len < 0 ) {
if ( ares__socket_try_again ( SOCKERRNO ) ) {
break ;
}
handle_conn_error ( conn , ARES_TRUE , ARES_ECONNREFUSED ) ;
return ;
# ifdef HAVE_RECVFROM
} else if ( ! same_address ( & from . sa , & conn - > server - > addr ) ) {
/* The address the response comes from does not match the address we
* sent the request to . Someone may be attempting to perform a cache
* poisoning attack . */
continue ;
# endif
} else {
process_answer ( channel , buf , ( size_t ) read_len , conn , ARES_FALSE , now ) ;
}
/* Try to read again only if *we* set up the socket, otherwise it may be
* a blocking socket and would cause recvfrom to hang . */
} while ( read_len > = 0 & & channel - > sock_funcs = = NULL ) ;
} }
static void read_packets ( ares_channel_t * channel , fd_set * read_fds , static void process_read ( ares_channel_t * channel , fd_set * read_fds ,
ares_socket_t read_fd , const ares_timeval_t * now ) ares_socket_t read_fd , const ares_timeval_t * now )
{ {
size_t i ; size_t i ;
ares_socket_t * socketlist = NULL ; ares_socket_t * socketlist = NULL ;
size_t num_sockets = 0 ; size_t num_sockets = 0 ;
ares_conn_t * conn = NULL ;
ares__llist_node_t * node = NULL ; ares__llist_node_t * node = NULL ;
if ( ! read_fds & & ( read_fd = = ARES_SOCKET_BAD ) ) { if ( ! read_fds & & ( read_fd = = ARES_SOCKET_BAD ) ) {
@ -503,13 +536,7 @@ static void read_packets(ares_channel_t *channel, fd_set *read_fds,
return ; return ;
} }
conn = ares__llist_node_val ( node ) ; read_conn ( ares__llist_node_val ( node ) , now ) ;
if ( conn - > flags & ARES_CONN_FLAG_TCP ) {
read_tcp_data ( channel , conn , now ) ;
} else {
read_udp_packets_fd ( channel , conn , now ) ;
}
return ; return ;
} }
@ -537,13 +564,7 @@ static void read_packets(ares_channel_t *channel, fd_set *read_fds,
return ; return ;
} }
conn = ares__llist_node_val ( node ) ; read_conn ( ares__llist_node_val ( node ) , now ) ;
if ( conn - > flags & ARES_CONN_FLAG_TCP ) {
read_tcp_data ( channel , conn , now ) ;
} else {
read_udp_packets_fd ( channel , conn , now ) ;
}
} }
ares_free ( socketlist ) ; ares_free ( socketlist ) ;
@ -607,7 +628,7 @@ done:
* the connection to be terminated after this call . */ * the connection to be terminated after this call . */
static ares_status_t process_answer ( ares_channel_t * channel , static ares_status_t process_answer ( ares_channel_t * channel ,
const unsigned char * abuf , size_t alen , const unsigned char * abuf , size_t alen ,
ares_conn_t * conn , ares_bool_t tcp , ares_conn_t * conn ,
const ares_timeval_t * now ) const ares_timeval_t * now )
{ {
ares_query_t * query ; ares_query_t * query ;
@ -618,6 +639,11 @@ static ares_status_t process_answer(ares_channel_t *channel,
ares_status_t status ; ares_status_t status ;
ares_bool_t is_cached = ARES_FALSE ; ares_bool_t is_cached = ARES_FALSE ;
/* UDP can have 0-byte messages, drop them to the ground */
if ( alen = = 0 ) {
return ARES_SUCCESS ;
}
/* Parse the response */ /* Parse the response */
status = ares_dns_parse ( abuf , alen , 0 , & rdnsrec ) ; status = ares_dns_parse ( abuf , alen , 0 , & rdnsrec ) ;
if ( status ! = ARES_SUCCESS ) { if ( status ! = ARES_SUCCESS ) {
@ -681,7 +707,8 @@ static ares_status_t process_answer(ares_channel_t *channel,
* don ' t accept the packet , and switch the query to TCP if we hadn ' t * don ' t accept the packet , and switch the query to TCP if we hadn ' t
* done so already . * done so already .
*/ */
if ( ares_dns_record_get_flags ( rdnsrec ) & ARES_FLAG_TC & & ! tcp & & if ( ares_dns_record_get_flags ( rdnsrec ) & ARES_FLAG_TC & &
! ( conn - > flags & ARES_CONN_FLAG_TCP ) & &
! ( channel - > flags & ARES_FLAG_IGNTC ) ) { ! ( channel - > flags & ARES_FLAG_IGNTC ) ) {
query - > using_tcp = ARES_TRUE ; query - > using_tcp = ARES_TRUE ;
ares__send_query ( query , now ) ; ares__send_query ( query , now ) ;
@ -971,9 +998,6 @@ static ares_status_t ares__conn_query_write(ares_conn_t *conn,
ares_query_t * query , ares_query_t * query ,
const ares_timeval_t * now ) const ares_timeval_t * now )
{ {
unsigned char * qbuf = NULL ;
size_t qbuf_len = 0 ;
ares_ssize_t len ;
ares_server_t * server = conn - > server ; ares_server_t * server = conn - > server ;
ares_channel_t * channel = server - > channel ; ares_channel_t * channel = server - > channel ;
ares_status_t status ; ares_status_t status ;
@ -983,64 +1007,33 @@ static ares_status_t ares__conn_query_write(ares_conn_t *conn,
return status ; return status ;
} }
if ( conn - > flags & ARES_CONN_FLAG_TCP ) { /* We write using the TCP format even for UDP, we just strip the length
size_t prior_len = ares__buf_len ( server - > tcp_send ) ; * before putting on the wire */
status = ares_dns_write_buf_tcp ( query - > query , conn - > out_buf ) ;
status = ares_dns_write_buf_tcp ( query - > query , server - > tcp_send ) ;
if ( status ! = ARES_SUCCESS ) {
return status ;
}
if ( conn - > flags & ARES_CONN_FLAG_TFO_INITIAL ) {
/* When using TFO, we need to put it on the wire immediately. */
size_t data_len ;
const unsigned char * data = NULL ;
data = ares__buf_peek ( server - > tcp_send , & data_len ) ;
len = ares__conn_write ( conn , data , data_len ) ;
if ( len < = 0 ) {
if ( ares__socket_try_again ( SOCKERRNO ) ) {
/* This means we must not have qualified for TFO, keep the data
* buffered , wait on write signal . */
return ARES_SUCCESS ;
}
/* TCP TFO might delay failure. Reflect that here */
return ARES_ECONNREFUSED ;
}
/* Consume what was written */
ares__buf_consume ( server - > tcp_send , ( size_t ) len ) ;
return ARES_SUCCESS ;
}
if ( prior_len = = 0 ) {
SOCK_STATE_CALLBACK ( channel , conn - > fd , 1 , 1 ) ;
}
return ARES_SUCCESS ;
}
/* UDP Here */
status = ares_dns_write ( query - > query , & qbuf , & qbuf_len ) ;
if ( status ! = ARES_SUCCESS ) { if ( status ! = ARES_SUCCESS ) {
return status ; return status ;
} }
len = ares__conn_write ( conn , qbuf , qbuf_len ) ; /* Not pending a TFO write and not connected, so we can't even try to
ares_free ( qbuf ) ; * write until we get a signal */
if ( conn - > flags & ARES_CONN_FLAG_TCP & &
! ( conn - > state_flags & ARES_CONN_STATE_CONNECTED ) & &
! ( conn - > flags & ARES_CONN_FLAG_TFO_INITIAL ) ) {
return ARES_SUCCESS ;
}
if ( len = = - 1 ) { /* Delay actual write if possible (TCP only, and only if callback
if ( ares__socket_try_again ( SOCKERRNO ) ) { * configured ) */
return ARES_ESERVFAIL ; if ( channel - > notify_pending_write_cb & & ! channel - > notify_pending_write & &
} conn - > flags & ARES_CONN_FLAG_TCP ) {
/* UDP is connection-less, but we might receive an ICMP unreachable which
channel - > notify_pending_write = ARES_TRUE ;
* means we can ' t talk to the remote host at all and that will be channel - > notify_pending_write_cb ( channel - > notify_pending_write_cb_data ) ;
* reflected here */ return ARES_SUCCESS ;
return ARES_ECONNREFUSED ;
} }
return ARES_SUCCESS ; /* Unfortunately we need to write right away and can't aggregate multiple
* queries into a single write . */
return ares__conn_flush ( conn ) ;
} }
ares_status_t ares__send_query ( ares_query_t * query , const ares_timeval_t * now ) ares_status_t ares__send_query ( ares_query_t * query , const ares_timeval_t * now )
@ -1150,6 +1143,7 @@ ares_status_t ares__send_query(ares_query_t *query, const ares_timeval_t *now)
query - > conn = conn ; query - > conn = conn ;
conn - > total_queries + + ; conn - > total_queries + + ;
return ARES_SUCCESS ; return ARES_SUCCESS ;
} }
@ -1213,36 +1207,6 @@ done:
return rv ; return rv ;
} }
static ares_bool_t same_address ( const struct sockaddr * sa ,
const struct ares_addr * aa )
{
const void * addr1 ;
const void * addr2 ;
if ( sa - > sa_family = = aa - > family ) {
switch ( aa - > family ) {
case AF_INET :
addr1 = & aa - > addr . addr4 ;
addr2 = & ( CARES_INADDR_CAST ( const struct sockaddr_in * , sa ) ) - > sin_addr ;
if ( memcmp ( addr1 , addr2 , sizeof ( aa - > addr . addr4 ) ) = = 0 ) {
return ARES_TRUE ; /* match */
}
break ;
case AF_INET6 :
addr1 = & aa - > addr . addr6 ;
addr2 =
& ( CARES_INADDR_CAST ( const struct sockaddr_in6 * , sa ) ) - > sin6_addr ;
if ( memcmp ( addr1 , addr2 , sizeof ( aa - > addr . addr6 ) ) = = 0 ) {
return ARES_TRUE ; /* match */
}
break ;
default :
break ; /* LCOV_EXCL_LINE */
}
}
return ARES_FALSE ; /* different */
}
static void ares_detach_query ( ares_query_t * query ) static void ares_detach_query ( ares_query_t * query )
{ {
/* Remove the query from all the lists in which it is linked */ /* Remove the query from all the lists in which it is linked */
Brad House
3 months ago
committed by
GitHub