Commit | Line | Data |
a0d0e21e |
1 | package Net::Ping; |
2 | |
b124990b |
3 | require 5.002; |
a0d0e21e |
4 | require Exporter; |
5 | |
a3b93737 |
6 | use strict; |
b124990b |
7 | use vars qw(@ISA @EXPORT $VERSION |
f569508e |
8 | $def_timeout $def_proto $max_datasize $pingstring $hires $source_verify $syn_forking); |
9 | use Fcntl qw( F_GETFL F_SETFL O_NONBLOCK ); |
10 | use Socket qw( SOCK_DGRAM SOCK_STREAM SOCK_RAW PF_INET SOL_SOCKET |
e82f584b |
11 | inet_aton inet_ntoa sockaddr_in ); |
69c74a9c |
12 | use POSIX qw( ECONNREFUSED EINPROGRESS EAGAIN WNOHANG ); |
f569508e |
13 | use FileHandle; |
a3b93737 |
14 | use Carp; |
a79c1648 |
15 | |
a0d0e21e |
16 | @ISA = qw(Exporter); |
a3b93737 |
17 | @EXPORT = qw(pingecho); |
9c36735d |
18 | $VERSION = "2.28"; |
a0d0e21e |
19 | |
a3b93737 |
20 | # Constants |
a0d0e21e |
21 | |
a3b93737 |
22 | $def_timeout = 5; # Default timeout to wait for a reply |
a5a165b1 |
23 | $def_proto = "tcp"; # Default protocol to use for pinging |
a3b93737 |
24 | $max_datasize = 1024; # Maximum data bytes in a packet |
b124990b |
25 | # The data we exchange with the server for the stream protocol |
26 | $pingstring = "pingschwingping!\n"; |
5d20095f |
27 | $source_verify = 1; # Default is to verify source endpoint |
f569508e |
28 | $syn_forking = 0; |
a0d0e21e |
29 | |
ef73e1db |
30 | if ($^O =~ /Win32/i) { |
31 | # Hack to avoid this Win32 spewage: |
32 | # Your vendor has not defined POSIX macro ECONNREFUSED |
33 | *ECONNREFUSED = sub {10061;}; # "Unknown Error" Special Win32 Response? |
f569508e |
34 | $syn_forking = 1; |
ef73e1db |
35 | }; |
36 | |
f569508e |
37 | # h2ph "asm/socket.h" |
38 | # require "asm/socket.ph"; |
39 | sub SO_BINDTODEVICE {25;} |
40 | |
a3b93737 |
41 | # Description: The pingecho() subroutine is provided for backward |
42 | # compatibility with the original Net::Ping. It accepts a host |
43 | # name/IP and an optional timeout in seconds. Create a tcp ping |
44 | # object and try pinging the host. The result of the ping is returned. |
a0d0e21e |
45 | |
a3b93737 |
46 | sub pingecho |
47 | { |
e82f584b |
48 | my ($host, # Name or IP number of host to ping |
49 | $timeout # Optional timeout in seconds |
50 | ) = @_; |
51 | my ($p); # A ping object |
a0d0e21e |
52 | |
e82f584b |
53 | $p = Net::Ping->new("tcp", $timeout); |
54 | $p->ping($host); # Going out of scope closes the connection |
a3b93737 |
55 | } |
a0d0e21e |
56 | |
a3b93737 |
57 | # Description: The new() method creates a new ping object. Optional |
58 | # parameters may be specified for the protocol to use, the timeout in |
59 | # seconds and the size in bytes of additional data which should be |
60 | # included in the packet. |
61 | # After the optional parameters are checked, the data is constructed |
62 | # and a socket is opened if appropriate. The object is returned. |
63 | |
64 | sub new |
65 | { |
e82f584b |
66 | my ($this, |
67 | $proto, # Optional protocol to use for pinging |
68 | $timeout, # Optional timeout in seconds |
f569508e |
69 | $data_size, # Optional additional bytes of data |
70 | $device, # Optional device to use |
e82f584b |
71 | ) = @_; |
72 | my $class = ref($this) || $this; |
73 | my $self = {}; |
74 | my ($cnt, # Count through data bytes |
75 | $min_datasize # Minimum data bytes required |
76 | ); |
77 | |
78 | bless($self, $class); |
79 | |
80 | $proto = $def_proto unless $proto; # Determine the protocol |
f569508e |
81 | croak('Protocol for ping must be "icmp", "udp", "tcp", "syn", "stream", or "external"') |
82 | unless $proto =~ m/^(icmp|udp|tcp|syn|stream|external)$/; |
e82f584b |
83 | $self->{"proto"} = $proto; |
84 | |
85 | $timeout = $def_timeout unless $timeout; # Determine the timeout |
86 | croak("Default timeout for ping must be greater than 0 seconds") |
87 | if $timeout <= 0; |
88 | $self->{"timeout"} = $timeout; |
89 | |
f569508e |
90 | $self->{"device"} = $device; |
91 | |
e82f584b |
92 | $min_datasize = ($proto eq "udp") ? 1 : 0; # Determine data size |
93 | $data_size = $min_datasize unless defined($data_size) && $proto ne "tcp"; |
94 | croak("Data for ping must be from $min_datasize to $max_datasize bytes") |
95 | if ($data_size < $min_datasize) || ($data_size > $max_datasize); |
96 | $data_size-- if $self->{"proto"} eq "udp"; # We provide the first byte |
97 | $self->{"data_size"} = $data_size; |
98 | |
99 | $self->{"data"} = ""; # Construct data bytes |
100 | for ($cnt = 0; $cnt < $self->{"data_size"}; $cnt++) |
101 | { |
102 | $self->{"data"} .= chr($cnt % 256); |
103 | } |
104 | |
105 | $self->{"local_addr"} = undef; # Don't bind by default |
106 | |
f569508e |
107 | $self->{"tcp_econnrefused"} = undef; # Default Connection refused behavior |
108 | |
e82f584b |
109 | $self->{"seq"} = 0; # For counting packets |
110 | if ($self->{"proto"} eq "udp") # Open a socket |
111 | { |
112 | $self->{"proto_num"} = (getprotobyname('udp'))[2] || |
113 | croak("Can't udp protocol by name"); |
114 | $self->{"port_num"} = (getservbyname('echo', 'udp'))[2] || |
115 | croak("Can't get udp echo port by name"); |
116 | $self->{"fh"} = FileHandle->new(); |
117 | socket($self->{"fh"}, PF_INET, SOCK_DGRAM, |
118 | $self->{"proto_num"}) || |
119 | croak("udp socket error - $!"); |
f569508e |
120 | if ($self->{'device'}) { |
121 | setsockopt($self->{"fh"}, SOL_SOCKET, SO_BINDTODEVICE(), pack("Z*", $self->{'device'})) |
122 | or croak "error binding to device $self->{'device'} $!"; |
123 | } |
e82f584b |
124 | } |
125 | elsif ($self->{"proto"} eq "icmp") |
126 | { |
f569508e |
127 | croak("icmp ping requires root privilege") if ($> and $^O ne 'VMS' and $^O ne 'cygwin'); |
e82f584b |
128 | $self->{"proto_num"} = (getprotobyname('icmp'))[2] || |
129 | croak("Can't get icmp protocol by name"); |
130 | $self->{"pid"} = $$ & 0xffff; # Save lower 16 bits of pid |
131 | $self->{"fh"} = FileHandle->new(); |
132 | socket($self->{"fh"}, PF_INET, SOCK_RAW, $self->{"proto_num"}) || |
133 | croak("icmp socket error - $!"); |
f569508e |
134 | if ($self->{'device'}) { |
135 | setsockopt($self->{"fh"}, SOL_SOCKET, SO_BINDTODEVICE(), pack("Z*", $self->{'device'})) |
136 | or croak "error binding to device $self->{'device'} $!"; |
137 | } |
e82f584b |
138 | } |
139 | elsif ($self->{"proto"} eq "tcp" || $self->{"proto"} eq "stream") |
140 | { |
141 | $self->{"proto_num"} = (getprotobyname('tcp'))[2] || |
142 | croak("Can't get tcp protocol by name"); |
143 | $self->{"port_num"} = (getservbyname('echo', 'tcp'))[2] || |
144 | croak("Can't get tcp echo port by name"); |
145 | $self->{"fh"} = FileHandle->new(); |
146 | } |
f569508e |
147 | elsif ($self->{"proto"} eq "syn") |
148 | { |
149 | $self->{"proto_num"} = (getprotobyname('tcp'))[2] || |
150 | croak("Can't get tcp protocol by name"); |
151 | $self->{"port_num"} = (getservbyname('echo', 'tcp'))[2] || |
152 | croak("Can't get tcp echo port by name"); |
153 | if ($syn_forking) { |
154 | $self->{"fork_rd"} = FileHandle->new(); |
155 | $self->{"fork_wr"} = FileHandle->new(); |
156 | pipe($self->{"fork_rd"}, $self->{"fork_wr"}); |
157 | $self->{"fh"} = FileHandle->new(); |
69c74a9c |
158 | $self->{"good"} = {}; |
159 | $self->{"bad"} = {}; |
f569508e |
160 | } else { |
161 | $self->{"wbits"} = ""; |
162 | $self->{"bad"} = {}; |
163 | } |
164 | $self->{"syn"} = {}; |
165 | $self->{"stop_time"} = 0; |
166 | } |
167 | elsif ($self->{"proto"} eq "external") |
168 | { |
169 | # No preliminary work needs to be done. |
170 | } |
e82f584b |
171 | |
172 | return($self); |
a3b93737 |
173 | } |
a0d0e21e |
174 | |
49afa5f6 |
175 | # Description: Set the local IP address from which pings will be sent. |
176 | # For ICMP and UDP pings, this calls bind() on the already-opened socket; |
177 | # for TCP pings, just saves the address to be used when the socket is |
178 | # opened. Returns non-zero if successful; croaks on error. |
179 | sub bind |
180 | { |
e82f584b |
181 | my ($self, |
182 | $local_addr # Name or IP number of local interface |
183 | ) = @_; |
184 | my ($ip # Packed IP number of $local_addr |
185 | ); |
186 | |
187 | croak("Usage: \$p->bind(\$local_addr)") unless @_ == 2; |
188 | croak("already bound") if defined($self->{"local_addr"}) && |
189 | ($self->{"proto"} eq "udp" || $self->{"proto"} eq "icmp"); |
190 | |
191 | $ip = inet_aton($local_addr); |
192 | croak("nonexistent local address $local_addr") unless defined($ip); |
193 | $self->{"local_addr"} = $ip; # Only used if proto is tcp |
194 | |
195 | if ($self->{"proto"} eq "udp" || $self->{"proto"} eq "icmp") |
196 | { |
197 | CORE::bind($self->{"fh"}, sockaddr_in(0, $ip)) || |
198 | croak("$self->{'proto'} bind error - $!"); |
199 | } |
200 | elsif ($self->{"proto"} ne "tcp") |
201 | { |
202 | croak("Unknown protocol \"$self->{proto}\" in bind()"); |
203 | } |
204 | |
205 | return 1; |
206 | } |
49afa5f6 |
207 | |
49afa5f6 |
208 | |
15d96390 |
209 | # Description: Allow UDP source endpoint comparision to be |
210 | # skipped for those remote interfaces that do |
211 | # not response from the same endpoint. |
212 | |
213 | sub source_verify |
214 | { |
215 | my $self = shift; |
5d20095f |
216 | $source_verify = 1 unless defined |
217 | ($source_verify = ((defined $self) && (ref $self)) ? shift() : $self); |
15d96390 |
218 | } |
219 | |
f569508e |
220 | # Description: Set whether or not the tcp connect |
221 | # behavior should enforce remote service availability |
222 | # as well as reachability. |
223 | |
224 | sub tcp_service_check |
225 | { |
226 | my $self = shift; |
227 | $self->{"tcp_econnrefused"} = 1 unless defined |
228 | ($self->{"tcp_econnrefused"} = shift()); |
229 | } |
230 | |
e82f584b |
231 | # Description: allows the module to use milliseconds as returned by |
232 | # the Time::HiRes module |
49afa5f6 |
233 | |
e82f584b |
234 | $hires = 0; |
235 | sub hires |
236 | { |
237 | my $self = shift; |
238 | $hires = 1 unless defined |
239 | ($hires = ((defined $self) && (ref $self)) ? shift() : $self); |
240 | require Time::HiRes if $hires; |
49afa5f6 |
241 | } |
242 | |
e82f584b |
243 | sub time |
244 | { |
245 | return $hires ? Time::HiRes::time() : CORE::time(); |
246 | } |
49afa5f6 |
247 | |
9c36735d |
248 | # Description: Sets or clears the O_NONBLOCK flag on a file handle. |
249 | sub socket_blocking_mode |
250 | { |
251 | my ($self, |
252 | $fh, # the file handle whose flags are to be modified |
253 | $block) = @_; # if true then set the blocking |
254 | # mode (clear O_NONBLOCK), otherwise |
255 | # set the non-blocking mode (set O_NONBLOCK) |
256 | |
257 | my $flags; |
258 | if ($flags = fcntl($fh, F_GETFL, 0)) { |
259 | $flags = $block ? ($flags & ~O_NONBLOCK) : ($flags | O_NONBLOCK); |
260 | if (!fcntl($fh, F_SETFL, $flags)) { |
261 | croak("fcntl F_SETFL: $!"); |
262 | } |
263 | } else { |
264 | croak("fcntl F_GETFL: $!"); |
265 | } |
266 | } |
267 | |
a3b93737 |
268 | # Description: Ping a host name or IP number with an optional timeout. |
269 | # First lookup the host, and return undef if it is not found. Otherwise |
b124990b |
270 | # perform the specific ping method based on the protocol. Return the |
a3b93737 |
271 | # result of the ping. |
272 | |
273 | sub ping |
274 | { |
e82f584b |
275 | my ($self, |
276 | $host, # Name or IP number of host to ping |
277 | $timeout, # Seconds after which ping times out |
278 | ) = @_; |
279 | my ($ip, # Packed IP number of $host |
280 | $ret, # The return value |
281 | $ping_time, # When ping began |
282 | ); |
283 | |
284 | croak("Usage: \$p->ping(\$host [, \$timeout])") unless @_ == 2 || @_ == 3; |
285 | $timeout = $self->{"timeout"} unless $timeout; |
286 | croak("Timeout must be greater than 0 seconds") if $timeout <= 0; |
287 | |
288 | $ip = inet_aton($host); |
289 | return(undef) unless defined($ip); # Does host exist? |
290 | |
291 | # Dispatch to the appropriate routine. |
292 | $ping_time = &time(); |
293 | if ($self->{"proto"} eq "external") { |
294 | $ret = $self->ping_external($ip, $timeout); |
295 | } |
296 | elsif ($self->{"proto"} eq "udp") { |
297 | $ret = $self->ping_udp($ip, $timeout); |
298 | } |
299 | elsif ($self->{"proto"} eq "icmp") { |
300 | $ret = $self->ping_icmp($ip, $timeout); |
301 | } |
302 | elsif ($self->{"proto"} eq "tcp") { |
303 | $ret = $self->ping_tcp($ip, $timeout); |
304 | } |
305 | elsif ($self->{"proto"} eq "stream") { |
306 | $ret = $self->ping_stream($ip, $timeout); |
f569508e |
307 | } |
308 | elsif ($self->{"proto"} eq "syn") { |
309 | $ret = $self->ping_syn($host, $ip, $ping_time, $ping_time+$timeout); |
e82f584b |
310 | } else { |
787ecdfa |
311 | croak("Unknown protocol \"$self->{proto}\" in ping()"); |
e82f584b |
312 | } |
313 | |
314 | return wantarray ? ($ret, &time() - $ping_time, inet_ntoa($ip)) : $ret; |
787ecdfa |
315 | } |
316 | |
317 | # Uses Net::Ping::External to do an external ping. |
318 | sub ping_external { |
319 | my ($self, |
320 | $ip, # Packed IP number of the host |
321 | $timeout # Seconds after which ping times out |
322 | ) = @_; |
323 | |
b124990b |
324 | eval { require Net::Ping::External; } |
325 | or croak('Protocol "external" not supported on your system: Net::Ping::External not found'); |
787ecdfa |
326 | return Net::Ping::External::ping(ip => $ip, timeout => $timeout); |
a3b93737 |
327 | } |
a0d0e21e |
328 | |
49afa5f6 |
329 | use constant ICMP_ECHOREPLY => 0; # ICMP packet types |
330 | use constant ICMP_ECHO => 8; |
9c36735d |
331 | use constant ICMP_STRUCT => "C2 n3 A"; # Structure of a minimal ICMP packet |
49afa5f6 |
332 | use constant SUBCODE => 0; # No ICMP subcode for ECHO and ECHOREPLY |
333 | use constant ICMP_FLAGS => 0; # No special flags for send or recv |
334 | use constant ICMP_PORT => 0; # No port with ICMP |
335 | |
a3b93737 |
336 | sub ping_icmp |
337 | { |
e82f584b |
338 | my ($self, |
339 | $ip, # Packed IP number of the host |
340 | $timeout # Seconds after which ping times out |
341 | ) = @_; |
342 | |
343 | my ($saddr, # sockaddr_in with port and ip |
344 | $checksum, # Checksum of ICMP packet |
345 | $msg, # ICMP packet to send |
346 | $len_msg, # Length of $msg |
347 | $rbits, # Read bits, filehandles for reading |
348 | $nfound, # Number of ready filehandles found |
349 | $finish_time, # Time ping should be finished |
350 | $done, # set to 1 when we are done |
351 | $ret, # Return value |
352 | $recv_msg, # Received message including IP header |
353 | $from_saddr, # sockaddr_in of sender |
354 | $from_port, # Port packet was sent from |
355 | $from_ip, # Packed IP of sender |
356 | $from_type, # ICMP type |
357 | $from_subcode, # ICMP subcode |
358 | $from_chk, # ICMP packet checksum |
359 | $from_pid, # ICMP packet id |
360 | $from_seq, # ICMP packet sequence |
361 | $from_msg # ICMP message |
362 | ); |
363 | |
364 | $self->{"seq"} = ($self->{"seq"} + 1) % 65536; # Increment sequence |
365 | $checksum = 0; # No checksum for starters |
366 | $msg = pack(ICMP_STRUCT . $self->{"data_size"}, ICMP_ECHO, SUBCODE, |
367 | $checksum, $self->{"pid"}, $self->{"seq"}, $self->{"data"}); |
368 | $checksum = Net::Ping->checksum($msg); |
369 | $msg = pack(ICMP_STRUCT . $self->{"data_size"}, ICMP_ECHO, SUBCODE, |
370 | $checksum, $self->{"pid"}, $self->{"seq"}, $self->{"data"}); |
371 | $len_msg = length($msg); |
372 | $saddr = sockaddr_in(ICMP_PORT, $ip); |
9c36735d |
373 | $self->{"from_ip"} = undef; |
374 | $self->{"from_type"} = undef; |
375 | $self->{"from_subcode"} = undef; |
e82f584b |
376 | send($self->{"fh"}, $msg, ICMP_FLAGS, $saddr); # Send the message |
377 | |
378 | $rbits = ""; |
379 | vec($rbits, $self->{"fh"}->fileno(), 1) = 1; |
380 | $ret = 0; |
381 | $done = 0; |
382 | $finish_time = &time() + $timeout; # Must be done by this time |
383 | while (!$done && $timeout > 0) # Keep trying if we have time |
384 | { |
385 | $nfound = select($rbits, undef, undef, $timeout); # Wait for packet |
386 | $timeout = $finish_time - &time(); # Get remaining time |
387 | if (!defined($nfound)) # Hmm, a strange error |
a3b93737 |
388 | { |
e82f584b |
389 | $ret = undef; |
390 | $done = 1; |
391 | } |
392 | elsif ($nfound) # Got a packet from somewhere |
393 | { |
394 | $recv_msg = ""; |
395 | $from_saddr = recv($self->{"fh"}, $recv_msg, 1500, ICMP_FLAGS); |
396 | ($from_port, $from_ip) = sockaddr_in($from_saddr); |
9c36735d |
397 | ($from_type, $from_subcode) = unpack("C2", substr($recv_msg, 20, 2)); |
398 | if ($from_type == ICMP_ECHOREPLY){ |
399 | ($from_pid, $from_seq) = unpack("n3", substr($recv_msg, 24, 4)); |
400 | } else { |
401 | ($from_pid, $from_seq) = unpack("n3", substr($recv_msg, 52, 4)); |
402 | } |
403 | $self->{"from_ip"} = $from_ip; |
404 | $self->{"from_type"} = $from_type; |
405 | $self->{"from_subcode"} = $from_subcode; |
406 | if (($from_pid == $self->{"pid"}) && # Does the packet check out? |
407 | ($from_seq == $self->{"seq"})) { |
408 | if ($from_type == ICMP_ECHOREPLY){ |
409 | $ret = 1; |
410 | } |
e82f584b |
411 | $done = 1; |
412 | } |
9c36735d |
413 | } else { # Oops, timed out |
e82f584b |
414 | $done = 1; |
415 | } |
416 | } |
417 | return $ret; |
a3b93737 |
418 | } |
419 | |
9c36735d |
420 | sub icmp_result { |
421 | my ($self) = @_; |
422 | my $ip = $self->{"from_ip"} || ""; |
423 | $ip = "\0\0\0\0" unless 4 == length $ip; |
424 | return (inet_ntoa($ip),($self->{"from_type"} || 0), ($self->{"from_subcode"} || 0)); |
425 | } |
426 | |
a3b93737 |
427 | # Description: Do a checksum on the message. Basically sum all of |
428 | # the short words and fold the high order bits into the low order bits. |
429 | |
430 | sub checksum |
431 | { |
e82f584b |
432 | my ($class, |
433 | $msg # The message to checksum |
434 | ) = @_; |
435 | my ($len_msg, # Length of the message |
436 | $num_short, # The number of short words in the message |
437 | $short, # One short word |
438 | $chk # The checksum |
439 | ); |
440 | |
441 | $len_msg = length($msg); |
442 | $num_short = int($len_msg / 2); |
443 | $chk = 0; |
9c36735d |
444 | foreach $short (unpack("n$num_short", $msg)) |
e82f584b |
445 | { |
446 | $chk += $short; |
447 | } # Add the odd byte in |
448 | $chk += (unpack("C", substr($msg, $len_msg - 1, 1)) << 8) if $len_msg % 2; |
449 | $chk = ($chk >> 16) + ($chk & 0xffff); # Fold high into low |
450 | return(~(($chk >> 16) + $chk) & 0xffff); # Again and complement |
a3b93737 |
451 | } |
452 | |
787ecdfa |
453 | |
b124990b |
454 | # Description: Perform a tcp echo ping. Since a tcp connection is |
455 | # host specific, we have to open and close each connection here. We |
456 | # can't just leave a socket open. Because of the robust nature of |
457 | # tcp, it will take a while before it gives up trying to establish a |
458 | # connection. Therefore, we use select() on a non-blocking socket to |
459 | # check against our timeout. No data bytes are actually |
460 | # sent since the successful establishment of a connection is proof |
461 | # enough of the reachability of the remote host. Also, tcp is |
462 | # expensive and doesn't need our help to add to the overhead. |
463 | |
464 | sub ping_tcp |
787ecdfa |
465 | { |
e82f584b |
466 | my ($self, |
467 | $ip, # Packed IP number of the host |
468 | $timeout # Seconds after which ping times out |
469 | ) = @_; |
470 | my ($ret # The return value |
471 | ); |
472 | |
9c36735d |
473 | $! = 0; |
e82f584b |
474 | $ret = $self -> tcp_connect( $ip, $timeout); |
f569508e |
475 | if (!$self->{"tcp_econnrefused"} && |
476 | $! == ECONNREFUSED) { |
477 | $ret = 1; # "Connection refused" means reachable |
478 | } |
e82f584b |
479 | $self->{"fh"}->close(); |
480 | return $ret; |
787ecdfa |
481 | } |
482 | |
b124990b |
483 | sub tcp_connect |
787ecdfa |
484 | { |
e82f584b |
485 | my ($self, |
486 | $ip, # Packed IP number of the host |
487 | $timeout # Seconds after which connect times out |
488 | ) = @_; |
489 | my ($saddr); # Packed IP and Port |
b124990b |
490 | |
e82f584b |
491 | $saddr = sockaddr_in($self->{"port_num"}, $ip); |
b124990b |
492 | |
e82f584b |
493 | my $ret = 0; # Default to unreachable |
b124990b |
494 | |
e82f584b |
495 | my $do_socket = sub { |
496 | socket($self->{"fh"}, PF_INET, SOCK_STREAM, $self->{"proto_num"}) || |
497 | croak("tcp socket error - $!"); |
498 | if (defined $self->{"local_addr"} && |
499 | !CORE::bind($self->{"fh"}, sockaddr_in(0, $self->{"local_addr"}))) { |
500 | croak("tcp bind error - $!"); |
501 | } |
f569508e |
502 | if ($self->{'device'}) { |
503 | setsockopt($self->{"fh"}, SOL_SOCKET, SO_BINDTODEVICE(), pack("Z*", $self->{'device'})) |
504 | or croak("error binding to device $self->{'device'} $!"); |
505 | } |
e82f584b |
506 | }; |
507 | my $do_connect = sub { |
9c36735d |
508 | $self->{"ip"} = $ip; |
509 | return ($ret = connect($self->{"fh"}, $saddr)); |
e82f584b |
510 | }; |
9c36735d |
511 | my $do_connect_nb = sub { |
512 | # Set O_NONBLOCK property on filehandle |
513 | $self->socket_blocking_mode($self->{"fh"}, 0); |
514 | |
515 | # start the connection attempt |
516 | if (!connect($self->{"fh"}, $saddr)) { |
517 | if ($! == ECONNREFUSED) { |
518 | $ret = 1 unless $self->{"tcp_econnrefused"}; |
519 | } else { |
520 | # EINPROGRESS is the expected error code after a connect() |
521 | # on a non-blocking socket |
522 | croak("tcp connect error - $!") if $! != EINPROGRESS; |
523 | |
524 | # wait for connection completion |
525 | my ($wbits, $wout); |
526 | $wout = $wbits = ""; |
527 | vec($wbits, $self->{"fh"}->fileno, 1) = 1; |
528 | |
529 | my $nfound = select(undef, ($wout = $wbits), undef, $timeout); |
530 | warn("select: $!") unless defined $nfound; |
531 | |
532 | if ($nfound && vec($wout, $self->{"fh"}->fileno, 1)) { |
533 | # the socket is ready for writing so the connection |
534 | # attempt completed. test whether the connection |
535 | # attempt was successful or not |
536 | |
537 | if (getpeername($self->{"fh"})) { |
538 | # Connection established to remote host |
539 | $ret = 1; |
540 | } else { |
541 | # TCP ACK will never come from this host |
542 | # because there was an error connecting. |
e82f584b |
543 | |
9c36735d |
544 | # This should set $! to the correct error. |
545 | my $char; |
546 | sysread($self->{"fh"},$char,1); |
547 | $! = ECONNREFUSED if ($! == EAGAIN && $^O =~ /cygwin/i); |
e82f584b |
548 | |
9c36735d |
549 | $ret = 1 if (!$self->{"tcp_econnrefused"} |
550 | && $! == ECONNREFUSED); |
551 | } |
552 | } else { |
553 | # the connection attempt timed out |
554 | } |
555 | } |
556 | } else { |
557 | # Connection established to remote host |
558 | $ret = 1; |
559 | } |
560 | |
561 | # Unset O_NONBLOCK property on filehandle |
562 | $self->socket_blocking_mode($self->{"fh"}, 1); |
563 | $self->{"ip"} = $ip; |
564 | return $ret; |
565 | }; |
566 | |
567 | if ($syn_forking) { |
568 | # Buggy Winsock API doesn't allow nonblocking connect. |
e82f584b |
569 | # Hence, if our OS is Windows, we need to create a separate |
570 | # process to do the blocking connect attempt. |
571 | |
572 | $| = 1; # Clear buffer prior to fork to prevent duplicate flushing. |
9c36735d |
573 | $self->{'tcp_chld'} = fork; |
574 | if (!$self->{'tcp_chld'}) { |
575 | if (!defined $self->{'tcp_chld'}) { |
e82f584b |
576 | # Fork did not work |
9c36735d |
577 | warn "Fork error: $!"; |
e82f584b |
578 | return 0; |
b124990b |
579 | } |
b124990b |
580 | &{ $do_socket }(); |
581 | |
e82f584b |
582 | # Try a slow blocking connect() call |
9c36735d |
583 | # and report the status to the parent. |
e82f584b |
584 | if ( &{ $do_connect }() ) { |
585 | $self->{"fh"}->close(); |
586 | # No error |
587 | exit 0; |
b124990b |
588 | } else { |
e82f584b |
589 | # Pass the error status to the parent |
590 | exit $!; |
b124990b |
591 | } |
e82f584b |
592 | } |
b124990b |
593 | |
e82f584b |
594 | &{ $do_socket }(); |
595 | |
596 | my $patience = &time() + $timeout; |
597 | |
9c36735d |
598 | my ($child, $child_errno); |
599 | $? = 0; $child_errno = 0; |
e82f584b |
600 | # Wait up to the timeout |
601 | # And clean off the zombie |
602 | do { |
9c36735d |
603 | $child = waitpid($self->{'tcp_chld'}, &WNOHANG()); |
604 | $child_errno = $? >> 8; |
e82f584b |
605 | select(undef, undef, undef, 0.1); |
9c36735d |
606 | } while &time() < $patience && $child != $self->{'tcp_chld'}; |
607 | |
608 | if ($child == $self->{'tcp_chld'}) { |
609 | if ($self->{"proto"} eq "stream") { |
610 | # We need the socket connected here, in parent |
611 | # Should be safe to connect because the child finished |
612 | # within the timeout |
613 | &{ $do_connect }(); |
614 | } |
e82f584b |
615 | } else { |
616 | # Time must have run out. |
e82f584b |
617 | # Put that choking client out of its misery |
9c36735d |
618 | kill "KILL", $self->{'tcp_chld'}; |
e82f584b |
619 | # Clean off the zombie |
9c36735d |
620 | waitpid($self->{'tcp_chld'}, 0); |
e82f584b |
621 | $ret = 0; |
b124990b |
622 | } |
9c36735d |
623 | delete $self->{'tcp_chld'}; |
624 | $! = $child_errno; |
625 | } else { |
e82f584b |
626 | # Otherwise don't waste the resources to fork |
627 | |
628 | &{ $do_socket }(); |
629 | |
9c36735d |
630 | &{ $do_connect_nb }(); |
e82f584b |
631 | } |
787ecdfa |
632 | |
e82f584b |
633 | return $ret; |
787ecdfa |
634 | } |
635 | |
9c36735d |
636 | sub DESTROY { |
637 | my $self = shift; |
638 | if ($self->{'proto'} eq 'tcp' && |
639 | $self->{'tcp_chld'}) { |
640 | # Put that choking client out of its misery |
641 | kill "KILL", $self->{'tcp_chld'}; |
642 | # Clean off the zombie |
643 | waitpid($self->{'tcp_chld'}, 0); |
644 | } |
645 | } |
646 | |
787ecdfa |
647 | # This writes the given string to the socket and then reads it |
648 | # back. It returns 1 on success, 0 on failure. |
649 | sub tcp_echo |
650 | { |
e82f584b |
651 | my $self = shift; |
652 | my $timeout = shift; |
653 | my $pingstring = shift; |
654 | |
655 | my $ret = undef; |
656 | my $time = &time(); |
657 | my $wrstr = $pingstring; |
658 | my $rdstr = ""; |
659 | |
660 | eval <<'EOM'; |
661 | do { |
662 | my $rin = ""; |
663 | vec($rin, $self->{"fh"}->fileno(), 1) = 1; |
664 | |
665 | my $rout = undef; |
666 | if($wrstr) { |
667 | $rout = ""; |
668 | vec($rout, $self->{"fh"}->fileno(), 1) = 1; |
669 | } |
670 | |
671 | if(select($rin, $rout, undef, ($time + $timeout) - &time())) { |
672 | |
673 | if($rout && vec($rout,$self->{"fh"}->fileno(),1)) { |
9c36735d |
674 | my $num = syswrite($self->{"fh"}, $wrstr, length $wrstr); |
e82f584b |
675 | if($num) { |
676 | # If it was a partial write, update and try again. |
677 | $wrstr = substr($wrstr,$num); |
678 | } else { |
679 | # There was an error. |
680 | $ret = 0; |
681 | } |
682 | } |
683 | |
684 | if(vec($rin,$self->{"fh"}->fileno(),1)) { |
685 | my $reply; |
686 | if(sysread($self->{"fh"},$reply,length($pingstring)-length($rdstr))) { |
687 | $rdstr .= $reply; |
688 | $ret = 1 if $rdstr eq $pingstring; |
689 | } else { |
690 | # There was an error. |
691 | $ret = 0; |
692 | } |
693 | } |
694 | |
695 | } |
696 | } until &time() > ($time + $timeout) || defined($ret); |
787ecdfa |
697 | EOM |
698 | |
e82f584b |
699 | return $ret; |
787ecdfa |
700 | } |
701 | |
787ecdfa |
702 | |
787ecdfa |
703 | |
787ecdfa |
704 | |
705 | # Description: Perform a stream ping. If the tcp connection isn't |
706 | # already open, it opens it. It then sends some data and waits for |
707 | # a reply. It leaves the stream open on exit. |
708 | |
709 | sub ping_stream |
710 | { |
e82f584b |
711 | my ($self, |
712 | $ip, # Packed IP number of the host |
713 | $timeout # Seconds after which ping times out |
714 | ) = @_; |
072620d9 |
715 | |
e82f584b |
716 | # Open the stream if it's not already open |
717 | if(!defined $self->{"fh"}->fileno()) { |
718 | $self->tcp_connect($ip, $timeout) or return 0; |
719 | } |
787ecdfa |
720 | |
e82f584b |
721 | croak "tried to switch servers while stream pinging" |
722 | if $self->{"ip"} ne $ip; |
723 | |
724 | return $self->tcp_echo($timeout, $pingstring); |
787ecdfa |
725 | } |
726 | |
727 | # Description: opens the stream. You would do this if you want to |
728 | # separate the overhead of opening the stream from the first ping. |
729 | |
730 | sub open |
731 | { |
e82f584b |
732 | my ($self, |
733 | $host, # Host or IP address |
734 | $timeout # Seconds after which open times out |
735 | ) = @_; |
736 | |
737 | my ($ip); # Packed IP number of the host |
738 | $ip = inet_aton($host); |
739 | $timeout = $self->{"timeout"} unless $timeout; |
740 | |
741 | if($self->{"proto"} eq "stream") { |
742 | if(defined($self->{"fh"}->fileno())) { |
743 | croak("socket is already open"); |
744 | } else { |
745 | $self->tcp_connect($ip, $timeout); |
b124990b |
746 | } |
e82f584b |
747 | } |
072620d9 |
748 | } |
749 | |
b124990b |
750 | |
a3b93737 |
751 | # Description: Perform a udp echo ping. Construct a message of |
752 | # at least the one-byte sequence number and any additional data bytes. |
753 | # Send the message out and wait for a message to come back. If we |
754 | # get a message, make sure all of its parts match. If they do, we are |
755 | # done. Otherwise go back and wait for the message until we run out |
756 | # of time. Return the result of our efforts. |
757 | |
49afa5f6 |
758 | use constant UDP_FLAGS => 0; # Nothing special on send or recv |
69c74a9c |
759 | # XXX - Use concept by rdw @ perlmonks |
760 | # http://perlmonks.thepen.com/42898.html |
a3b93737 |
761 | sub ping_udp |
762 | { |
e82f584b |
763 | my ($self, |
764 | $ip, # Packed IP number of the host |
765 | $timeout # Seconds after which ping times out |
766 | ) = @_; |
767 | |
768 | my ($saddr, # sockaddr_in with port and ip |
769 | $ret, # The return value |
770 | $msg, # Message to be echoed |
771 | $finish_time, # Time ping should be finished |
e82f584b |
772 | $done, # Set to 1 when we are done pinging |
773 | $rbits, # Read bits, filehandles for reading |
774 | $nfound, # Number of ready filehandles found |
775 | $from_saddr, # sockaddr_in of sender |
776 | $from_msg, # Characters echoed by $host |
777 | $from_port, # Port message was echoed from |
778 | $from_ip # Packed IP number of sender |
779 | ); |
780 | |
781 | $saddr = sockaddr_in($self->{"port_num"}, $ip); |
782 | $self->{"seq"} = ($self->{"seq"} + 1) % 256; # Increment sequence |
783 | $msg = chr($self->{"seq"}) . $self->{"data"}; # Add data if any |
784 | send($self->{"fh"}, $msg, UDP_FLAGS, $saddr); # Send it |
785 | |
786 | $rbits = ""; |
787 | vec($rbits, $self->{"fh"}->fileno(), 1) = 1; |
788 | $ret = 0; # Default to unreachable |
789 | $done = 0; |
e82f584b |
790 | $finish_time = &time() + $timeout; # Ping needs to be done by then |
791 | while (!$done && $timeout > 0) |
792 | { |
793 | $nfound = select($rbits, undef, undef, $timeout); # Wait for response |
794 | $timeout = $finish_time - &time(); # Get remaining time |
795 | |
796 | if (!defined($nfound)) # Hmm, a strange error |
a3b93737 |
797 | { |
e82f584b |
798 | $ret = undef; |
799 | $done = 1; |
a3b93737 |
800 | } |
e82f584b |
801 | elsif ($nfound) # A packet is waiting |
802 | { |
803 | $from_msg = ""; |
804 | $from_saddr = recv($self->{"fh"}, $from_msg, 1500, UDP_FLAGS) |
805 | or last; # For example an unreachable host will make recv() fail. |
806 | ($from_port, $from_ip) = sockaddr_in($from_saddr); |
5d20095f |
807 | if (!$source_verify || |
15d96390 |
808 | (($from_ip eq $ip) && # Does the packet check out? |
809 | ($from_port == $self->{"port_num"}) && |
810 | ($from_msg eq $msg))) |
e82f584b |
811 | { |
812 | $ret = 1; # It's a winner |
813 | $done = 1; |
814 | } |
815 | } |
816 | else # Oops, timed out |
817 | { |
818 | $done = 1; |
819 | } |
820 | } |
a5a165b1 |
821 | return $ret; |
b124990b |
822 | } |
a0d0e21e |
823 | |
f569508e |
824 | # Description: Send a TCP SYN packet to host specified. |
825 | sub ping_syn |
826 | { |
827 | my $self = shift; |
828 | my $host = shift; |
829 | my $ip = shift; |
830 | my $start_time = shift; |
831 | my $stop_time = shift; |
832 | |
833 | if ($syn_forking) { |
834 | return $self->ping_syn_fork($host, $ip, $start_time, $stop_time); |
835 | } |
836 | |
837 | my $fh = FileHandle->new(); |
838 | my $saddr = sockaddr_in($self->{"port_num"}, $ip); |
839 | |
840 | # Create TCP socket |
841 | if (!socket ($fh, PF_INET, SOCK_STREAM, $self->{"proto_num"})) { |
842 | croak("tcp socket error - $!"); |
843 | } |
844 | |
845 | if (defined $self->{"local_addr"} && |
846 | !CORE::bind($fh, sockaddr_in(0, $self->{"local_addr"}))) { |
847 | croak("tcp bind error - $!"); |
848 | } |
849 | |
850 | if ($self->{'device'}) { |
851 | setsockopt($fh, SOL_SOCKET, SO_BINDTODEVICE(), pack("Z*", $self->{'device'})) |
852 | or croak("error binding to device $self->{'device'} $!"); |
853 | } |
854 | |
855 | # Set O_NONBLOCK property on filehandle |
9c36735d |
856 | $self->socket_blocking_mode($fh, 0); |
f569508e |
857 | |
858 | # Attempt the non-blocking connect |
859 | # by just sending the TCP SYN packet |
860 | if (connect($fh, $saddr)) { |
861 | # Non-blocking, yet still connected? |
69c74a9c |
862 | # Must have connected very quickly, |
863 | # or else it wasn't very non-blocking. |
864 | #warn "WARNING: Nonblocking connect connected anyway? ($^O)"; |
865 | } else { |
f569508e |
866 | # Error occurred connecting. |
69c74a9c |
867 | if ($! == EINPROGRESS) { |
868 | # The connection is just still in progress. |
869 | # This is the expected condition. |
870 | } else { |
871 | # Just save the error and continue on. |
872 | # The ack() can check the status later. |
f569508e |
873 | $self->{"bad"}->{$host} = $!; |
f569508e |
874 | } |
875 | } |
876 | |
877 | my $entry = [ $host, $ip, $fh, $start_time, $stop_time ]; |
878 | $self->{"syn"}->{$fh->fileno} = $entry; |
879 | if ($self->{"stop_time"} < $stop_time) { |
880 | $self->{"stop_time"} = $stop_time; |
881 | } |
882 | vec($self->{"wbits"}, $fh->fileno, 1) = 1; |
883 | |
884 | return 1; |
885 | } |
886 | |
887 | sub ping_syn_fork { |
888 | my ($self, $host, $ip, $start_time, $stop_time) = @_; |
889 | |
890 | # Buggy Winsock API doesn't allow nonblocking connect. |
891 | # Hence, if our OS is Windows, we need to create a separate |
892 | # process to do the blocking connect attempt. |
893 | my $pid = fork(); |
894 | if (defined $pid) { |
895 | if ($pid) { |
896 | # Parent process |
897 | my $entry = [ $host, $ip, $pid, $start_time, $stop_time ]; |
898 | $self->{"syn"}->{$pid} = $entry; |
899 | if ($self->{"stop_time"} < $stop_time) { |
900 | $self->{"stop_time"} = $stop_time; |
901 | } |
902 | } else { |
903 | # Child process |
904 | my $saddr = sockaddr_in($self->{"port_num"}, $ip); |
905 | |
906 | # Create TCP socket |
907 | if (!socket ($self->{"fh"}, PF_INET, SOCK_STREAM, $self->{"proto_num"})) { |
908 | croak("tcp socket error - $!"); |
909 | } |
910 | |
911 | if (defined $self->{"local_addr"} && |
912 | !CORE::bind($self->{"fh"}, sockaddr_in(0, $self->{"local_addr"}))) { |
913 | croak("tcp bind error - $!"); |
914 | } |
915 | |
916 | if ($self->{'device'}) { |
917 | setsockopt($self->{"fh"}, SOL_SOCKET, SO_BINDTODEVICE(), pack("Z*", $self->{'device'})) |
918 | or croak("error binding to device $self->{'device'} $!"); |
919 | } |
920 | |
921 | $!=0; |
922 | # Try to connect (could take a long time) |
923 | connect($self->{"fh"}, $saddr); |
924 | # Notify parent of connect error status |
925 | my $err = $!+0; |
926 | my $wrstr = "$$ $err"; |
9c36735d |
927 | # Force to 16 chars including \n |
928 | $wrstr .= " "x(15 - length $wrstr). "\n"; |
929 | syswrite($self->{"fork_wr"}, $wrstr, length $wrstr); |
f569508e |
930 | exit; |
931 | } |
932 | } else { |
933 | # fork() failed? |
934 | die "fork: $!"; |
935 | } |
936 | return 1; |
937 | } |
938 | |
939 | # Description: Wait for TCP ACK from host specified |
940 | # from ping_syn above. If no host is specified, wait |
941 | # for TCP ACK from any of the hosts in the SYN queue. |
942 | sub ack |
943 | { |
944 | my $self = shift; |
945 | |
946 | if ($self->{"proto"} eq "syn") { |
947 | if ($syn_forking) { |
948 | my @answer = $self->ack_unfork(shift); |
949 | return wantarray ? @answer : $answer[0]; |
950 | } |
951 | my $wbits = ""; |
952 | my $stop_time = 0; |
953 | if (my $host = shift) { |
954 | # Host passed as arg |
955 | if (exists $self->{"bad"}->{$host}) { |
69c74a9c |
956 | if (!$self->{"tcp_econnrefused"} && |
957 | $self->{"bad"}->{ $host } && |
958 | (($! = ECONNREFUSED)>0) && |
959 | $self->{"bad"}->{ $host } eq "$!") { |
960 | # "Connection refused" means reachable |
961 | # Good, continue |
962 | } else { |
963 | # ECONNREFUSED means no good |
964 | return (); |
965 | } |
f569508e |
966 | } |
967 | my $host_fd = undef; |
968 | foreach my $fd (keys %{ $self->{"syn"} }) { |
969 | my $entry = $self->{"syn"}->{$fd}; |
970 | if ($entry->[0] eq $host) { |
971 | $host_fd = $fd; |
972 | $stop_time = $entry->[4] |
973 | || croak("Corrupted SYN entry for [$host]"); |
974 | last; |
975 | } |
976 | } |
977 | croak("ack called on [$host] without calling ping first!") |
978 | unless defined $host_fd; |
979 | vec($wbits, $host_fd, 1) = 1; |
980 | } else { |
981 | # No $host passed so scan all hosts |
982 | # Use the latest stop_time |
983 | $stop_time = $self->{"stop_time"}; |
984 | # Use all the bits |
985 | $wbits = $self->{"wbits"}; |
986 | } |
987 | |
9c36735d |
988 | while ($wbits !~ /^\0*\z/) { |
f569508e |
989 | my $timeout = $stop_time - &time(); |
990 | # Force a minimum of 10 ms timeout. |
69c74a9c |
991 | $timeout = 0.01 if $timeout <= 0.01; |
992 | |
993 | my $winner_fd = undef; |
994 | my $wout = $wbits; |
995 | my $fd = 0; |
996 | # Do "bad" fds from $wbits first |
9c36735d |
997 | while ($wout !~ /^\0*\z/) { |
69c74a9c |
998 | if (vec($wout, $fd, 1)) { |
999 | # Wipe it from future scanning. |
1000 | vec($wout, $fd, 1) = 0; |
1001 | if (my $entry = $self->{"syn"}->{$fd}) { |
1002 | if ($self->{"bad"}->{ $entry->[0] }) { |
1003 | $winner_fd = $fd; |
1004 | last; |
1005 | } |
1006 | } |
1007 | } |
1008 | $fd++; |
1009 | } |
1010 | |
1011 | if (defined($winner_fd) or my $nfound = select(undef, ($wout=$wbits), undef, $timeout)) { |
1012 | if (defined $winner_fd) { |
1013 | $fd = $winner_fd; |
1014 | } else { |
1015 | # Done waiting for one of the ACKs |
1016 | $fd = 0; |
1017 | # Determine which one |
9c36735d |
1018 | while ($wout !~ /^\0*\z/ && |
69c74a9c |
1019 | !vec($wout, $fd, 1)) { |
1020 | $fd++; |
1021 | } |
f569508e |
1022 | } |
1023 | if (my $entry = $self->{"syn"}->{$fd}) { |
69c74a9c |
1024 | # Wipe it from future scanning. |
1025 | delete $self->{"syn"}->{$fd}; |
1026 | vec($self->{"wbits"}, $fd, 1) = 0; |
1027 | vec($wbits, $fd, 1) = 0; |
1028 | if (!$self->{"tcp_econnrefused"} && |
1029 | $self->{"bad"}->{ $entry->[0] } && |
1030 | (($! = ECONNREFUSED)>0) && |
1031 | $self->{"bad"}->{ $entry->[0] } eq "$!") { |
1032 | # "Connection refused" means reachable |
1033 | # Good, continue |
1034 | } elsif (getpeername($entry->[2])) { |
f569508e |
1035 | # Connection established to remote host |
69c74a9c |
1036 | # Good, continue |
f569508e |
1037 | } else { |
1038 | # TCP ACK will never come from this host |
1039 | # because there was an error connecting. |
1040 | |
f569508e |
1041 | # This should set $! to the correct error. |
1042 | my $char; |
9c36735d |
1043 | sysread($entry->[2],$char,1); |
f569508e |
1044 | # Store the excuse why the connection failed. |
1045 | $self->{"bad"}->{$entry->[0]} = $!; |
1046 | if (!$self->{"tcp_econnrefused"} && |
69c74a9c |
1047 | (($! == ECONNREFUSED) || |
1048 | ($! == EAGAIN && $^O =~ /cygwin/i))) { |
f569508e |
1049 | # "Connection refused" means reachable |
69c74a9c |
1050 | # Good, continue |
1051 | } else { |
1052 | # No good, try the next socket... |
1053 | next; |
f569508e |
1054 | } |
f569508e |
1055 | } |
69c74a9c |
1056 | # Everything passed okay, return the answer |
1057 | return wantarray ? |
1058 | ($entry->[0], &time() - $entry->[3], inet_ntoa($entry->[1])) |
1059 | : $entry->[0]; |
f569508e |
1060 | } else { |
1061 | warn "Corrupted SYN entry: unknown fd [$fd] ready!"; |
1062 | vec($wbits, $fd, 1) = 0; |
1063 | vec($self->{"wbits"}, $fd, 1) = 0; |
1064 | } |
1065 | } elsif (defined $nfound) { |
1066 | # Timed out waiting for ACK |
1067 | foreach my $fd (keys %{ $self->{"syn"} }) { |
1068 | if (vec($wbits, $fd, 1)) { |
1069 | my $entry = $self->{"syn"}->{$fd}; |
1070 | $self->{"bad"}->{$entry->[0]} = "Timed out"; |
1071 | vec($wbits, $fd, 1) = 0; |
1072 | vec($self->{"wbits"}, $fd, 1) = 0; |
1073 | delete $self->{"syn"}->{$fd}; |
1074 | } |
1075 | } |
1076 | } else { |
1077 | # Weird error occurred with select() |
1078 | warn("select: $!"); |
1079 | $self->{"syn"} = {}; |
1080 | $wbits = ""; |
1081 | } |
1082 | } |
1083 | } |
1084 | return (); |
1085 | } |
1086 | |
1087 | sub ack_unfork { |
69c74a9c |
1088 | my ($self,$host) = @_; |
f569508e |
1089 | my $stop_time = $self->{"stop_time"}; |
69c74a9c |
1090 | if ($host) { |
f569508e |
1091 | # Host passed as arg |
69c74a9c |
1092 | if (my $entry = $self->{"good"}->{$host}) { |
1093 | delete $self->{"good"}->{$host}; |
1094 | return ($entry->[0], &time() - $entry->[3], inet_ntoa($entry->[1])); |
1095 | } |
f569508e |
1096 | } |
1097 | |
1098 | my $rbits = ""; |
1099 | my $timeout; |
69c74a9c |
1100 | |
f569508e |
1101 | if (keys %{ $self->{"syn"} }) { |
1102 | # Scan all hosts that are left |
1103 | vec($rbits, fileno($self->{"fork_rd"}), 1) = 1; |
1104 | $timeout = $stop_time - &time(); |
69c74a9c |
1105 | # Force a minimum of 10 ms timeout. |
1106 | $timeout = 0.01 if $timeout < 0.01; |
f569508e |
1107 | } else { |
1108 | # No hosts left to wait for |
1109 | $timeout = 0; |
1110 | } |
1111 | |
1112 | if ($timeout > 0) { |
69c74a9c |
1113 | my $nfound; |
1114 | while ( keys %{ $self->{"syn"} } and |
1115 | $nfound = select((my $rout=$rbits), undef, undef, $timeout)) { |
f569508e |
1116 | # Done waiting for one of the ACKs |
9c36735d |
1117 | if (!sysread($self->{"fork_rd"}, $_, 16)) { |
f569508e |
1118 | # Socket closed, which means all children are done. |
1119 | return (); |
1120 | } |
1121 | my ($pid, $how) = split; |
1122 | if ($pid) { |
1123 | # Flush the zombie |
1124 | waitpid($pid, 0); |
1125 | if (my $entry = $self->{"syn"}->{$pid}) { |
1126 | # Connection attempt to remote host is done |
1127 | delete $self->{"syn"}->{$pid}; |
1128 | if (!$how || # If there was no error connecting |
1129 | (!$self->{"tcp_econnrefused"} && |
1130 | $how == ECONNREFUSED)) { # "Connection refused" means reachable |
69c74a9c |
1131 | if ($host && $entry->[0] ne $host) { |
1132 | # A good connection, but not the host we need. |
1133 | # Move it from the "syn" hash to the "good" hash. |
1134 | $self->{"good"}->{$entry->[0]} = $entry; |
1135 | # And wait for the next winner |
1136 | next; |
1137 | } |
f569508e |
1138 | return ($entry->[0], &time() - $entry->[3], inet_ntoa($entry->[1])); |
1139 | } |
1140 | } else { |
1141 | # Should never happen |
1142 | die "Unknown ping from pid [$pid]"; |
1143 | } |
1144 | } else { |
1145 | die "Empty response from status socket?"; |
1146 | } |
69c74a9c |
1147 | } |
1148 | if (defined $nfound) { |
f569508e |
1149 | # Timed out waiting for ACK status |
1150 | } else { |
1151 | # Weird error occurred with select() |
1152 | warn("select: $!"); |
1153 | } |
1154 | } |
1155 | if (my @synners = keys %{ $self->{"syn"} }) { |
1156 | # Kill all the synners |
1157 | kill 9, @synners; |
1158 | foreach my $pid (@synners) { |
1159 | # Wait for the deaths to finish |
1160 | # Then flush off the zombie |
1161 | waitpid($pid, 0); |
1162 | } |
1163 | } |
1164 | $self->{"syn"} = {}; |
1165 | return (); |
1166 | } |
1167 | |
1168 | # Description: Tell why the ack() failed |
1169 | sub nack { |
1170 | my $self = shift; |
1171 | my $host = shift || croak('Usage> nack($failed_ack_host)'); |
1172 | return $self->{"bad"}->{$host} || undef; |
1173 | } |
1174 | |
1175 | # Description: Close the connection. |
a3b93737 |
1176 | |
1177 | sub close |
1178 | { |
e82f584b |
1179 | my ($self) = @_; |
a3b93737 |
1180 | |
f569508e |
1181 | if ($self->{"proto"} eq "syn") { |
1182 | delete $self->{"syn"}; |
1183 | } elsif ($self->{"proto"} eq "tcp") { |
1184 | # The connection will already be closed |
1185 | } else { |
1186 | $self->{"fh"}->close(); |
1187 | } |
a3b93737 |
1188 | } |
1189 | |
1190 | |
a0d0e21e |
1191 | 1; |
8e07c86e |
1192 | __END__ |
1193 | |
8e07c86e |
1194 | =head1 NAME |
1195 | |
a3b93737 |
1196 | Net::Ping - check a remote host for reachability |
8e07c86e |
1197 | |
1198 | =head1 SYNOPSIS |
1199 | |
1200 | use Net::Ping; |
8e07c86e |
1201 | |
a3b93737 |
1202 | $p = Net::Ping->new(); |
1203 | print "$host is alive.\n" if $p->ping($host); |
1204 | $p->close(); |
1205 | |
1206 | $p = Net::Ping->new("icmp"); |
49afa5f6 |
1207 | $p->bind($my_addr); # Specify source interface of pings |
a3b93737 |
1208 | foreach $host (@host_array) |
1209 | { |
1210 | print "$host is "; |
1211 | print "NOT " unless $p->ping($host, 2); |
1212 | print "reachable.\n"; |
1213 | sleep(1); |
1214 | } |
1215 | $p->close(); |
b124990b |
1216 | |
a3b93737 |
1217 | $p = Net::Ping->new("tcp", 2); |
b124990b |
1218 | # Try connecting to the www port instead of the echo port |
1219 | $p->{port_num} = getservbyname("http", "tcp"); |
a3b93737 |
1220 | while ($stop_time > time()) |
1221 | { |
1222 | print "$host not reachable ", scalar(localtime()), "\n" |
1223 | unless $p->ping($host); |
1224 | sleep(300); |
1225 | } |
1226 | undef($p); |
b124990b |
1227 | |
f569508e |
1228 | # Like tcp protocol, but with many hosts |
1229 | $p = Net::Ping->new("syn"); |
1230 | $p->{port_num} = getservbyname("http", "tcp"); |
1231 | foreach $host (@host_array) { |
1232 | $p->ping($host); |
1233 | } |
1234 | while (($host,$rtt,$ip) = $p->ack) { |
1235 | print "HOST: $host [$ip] ACKed in $rtt seconds.\n"; |
1236 | } |
1237 | |
e82f584b |
1238 | # High precision syntax (requires Time::HiRes) |
1239 | $p = Net::Ping->new(); |
1240 | $p->hires(); |
1241 | ($ret, $duration, $ip) = $p->ping($host, 5.5); |
1242 | printf("$host [ip: $ip] is alive (packet return time: %.2f ms)\n", 1000 * $duration) |
1243 | if $ret; |
1244 | $p->close(); |
1245 | |
a3b93737 |
1246 | # For backward compatibility |
1247 | print "$host is alive.\n" if pingecho($host); |
8e07c86e |
1248 | |
a3b93737 |
1249 | =head1 DESCRIPTION |
8e07c86e |
1250 | |
a3b93737 |
1251 | This module contains methods to test the reachability of remote |
1252 | hosts on a network. A ping object is first created with optional |
1253 | parameters, a variable number of hosts may be pinged multiple |
1254 | times and then the connection is closed. |
1255 | |
f569508e |
1256 | You may choose one of six different protocols to use for the |
1257 | ping. The "tcp" protocol is the default. Note that a live remote host |
b124990b |
1258 | may still fail to be pingable by one or more of these protocols. For |
f569508e |
1259 | example, www.microsoft.com is generally alive but not "icmp" pingable. |
787ecdfa |
1260 | |
b124990b |
1261 | With the "tcp" protocol the ping() method attempts to establish a |
1262 | connection to the remote host's echo port. If the connection is |
1263 | successfully established, the remote host is considered reachable. No |
1264 | data is actually echoed. This protocol does not require any special |
9c36735d |
1265 | privileges but has higher overhead than the "udp" and "icmp" protocols. |
072620d9 |
1266 | |
b124990b |
1267 | Specifying the "udp" protocol causes the ping() method to send a udp |
a3b93737 |
1268 | packet to the remote host's echo port. If the echoed packet is |
1269 | received from the remote host and the received packet contains the |
1270 | same data as the packet that was sent, the remote host is considered |
1271 | reachable. This protocol does not require any special privileges. |
b124990b |
1272 | It should be borne in mind that, for a udp ping, a host |
787ecdfa |
1273 | will be reported as unreachable if it is not running the |
b124990b |
1274 | appropriate echo service. For Unix-like systems see L<inetd(8)> |
1275 | for more information. |
787ecdfa |
1276 | |
b124990b |
1277 | If the "icmp" protocol is specified, the ping() method sends an icmp |
1278 | echo message to the remote host, which is what the UNIX ping program |
1279 | does. If the echoed message is received from the remote host and |
1280 | the echoed information is correct, the remote host is considered |
1281 | reachable. Specifying the "icmp" protocol requires that the program |
1282 | be run as root or that the program be setuid to root. |
787ecdfa |
1283 | |
b124990b |
1284 | If the "external" protocol is specified, the ping() method attempts to |
1285 | use the C<Net::Ping::External> module to ping the remote host. |
1286 | C<Net::Ping::External> interfaces with your system's default C<ping> |
1287 | utility to perform the ping, and generally produces relatively |
787ecdfa |
1288 | accurate results. If C<Net::Ping::External> if not installed on your |
1289 | system, specifying the "external" protocol will result in an error. |
edc5bd88 |
1290 | |
f569508e |
1291 | If the "syn" protocol is specified, the ping() method will only |
1292 | send a TCP SYN packet to the remote host then immediately return. |
1293 | If the syn packet was sent successfully, it will return a true value, |
1294 | otherwise it will return false. NOTE: Unlike the other protocols, |
1295 | the return value does NOT determine if the remote host is alive or |
1296 | not since the full TCP three-way handshake may not have completed |
1297 | yet. The remote host is only considered reachable if it receives |
1298 | a TCP ACK within the timeout specifed. To begin waiting for the |
1299 | ACK packets, use the ack() method as explained below. Use the |
1300 | "syn" protocol instead the "tcp" protocol to determine reachability |
1301 | of multiple destinations simultaneously by sending parallel TCP |
1302 | SYN packets. It will not block while testing each remote host. |
1303 | demo/fping is provided in this distribution to demonstrate the |
1304 | "syn" protocol as an example. |
1305 | This protocol does not require any special privileges. |
1306 | |
a3b93737 |
1307 | =head2 Functions |
1308 | |
1309 | =over 4 |
1310 | |
f569508e |
1311 | =item Net::Ping->new([$proto [, $def_timeout [, $bytes [, $device ]]]]); |
a3b93737 |
1312 | |
1313 | Create a new ping object. All of the parameters are optional. $proto |
1314 | specifies the protocol to use when doing a ping. The current choices |
f569508e |
1315 | are "tcp", "udp", "icmp", "stream", "syn", or "external". |
1316 | The default is "tcp". |
a3b93737 |
1317 | |
1318 | If a default timeout ($def_timeout) in seconds is provided, it is used |
1319 | when a timeout is not given to the ping() method (below). The timeout |
1320 | must be greater than 0 and the default, if not specified, is 5 seconds. |
1321 | |
1322 | If the number of data bytes ($bytes) is given, that many data bytes |
1323 | are included in the ping packet sent to the remote host. The number of |
1324 | data bytes is ignored if the protocol is "tcp". The minimum (and |
1325 | default) number of data bytes is 1 if the protocol is "udp" and 0 |
1326 | otherwise. The maximum number of data bytes that can be specified is |
1327 | 1024. |
1328 | |
f569508e |
1329 | If $device is given, this device is used to bind the source endpoint |
1330 | before sending the ping packet. I beleive this only works with |
1331 | superuser privileges and with udp and icmp protocols at this time. |
1332 | |
5d20095f |
1333 | =item $p->ping($host [, $timeout]); |
1334 | |
1335 | Ping the remote host and wait for a response. $host can be either the |
1336 | hostname or the IP number of the remote host. The optional timeout |
1337 | must be greater than 0 seconds and defaults to whatever was specified |
1338 | when the ping object was created. Returns a success flag. If the |
1339 | hostname cannot be found or there is a problem with the IP number, the |
1340 | success flag returned will be undef. Otherwise, the success flag will |
1341 | be 1 if the host is reachable and 0 if it is not. For most practical |
1342 | purposes, undef and 0 and can be treated as the same case. In array |
f569508e |
1343 | context, the elapsed time as well as the string form of the ip the |
1344 | host resolved to are also returned. The elapsed time value will |
5d20095f |
1345 | be a float, as retuned by the Time::HiRes::time() function, if hires() |
1346 | has been previously called, otherwise it is returned as an integer. |
1347 | |
15d96390 |
1348 | =item $p->source_verify( { 0 | 1 } ); |
1349 | |
1350 | Allows source endpoint verification to be enabled or disabled. |
1351 | This is useful for those remote destinations with multiples |
1352 | interfaces where the response may not originate from the same |
1353 | endpoint that the original destination endpoint was sent to. |
5d20095f |
1354 | This only affects udp and icmp protocol pings. |
15d96390 |
1355 | |
1356 | This is enabled by default. |
1357 | |
f569508e |
1358 | =item $p->tcp_service_check( { 0 | 1 } ); |
1359 | |
1360 | Set whether or not the tcp connect behavior should enforce |
1361 | remote service availability as well as reachability. Normally, |
1362 | if the remote server reported ECONNREFUSED, it must have been |
1363 | reachable because of the status packet that it reported. |
1364 | With this option enabled, the full three-way tcp handshake |
1365 | must have been established successfully before it will |
1366 | claim it is reachable. NOTE: It still does nothing more |
1367 | than connect and disconnect. It does not speak any protocol |
1368 | (i.e., HTTP or FTP) to ensure the remote server is sane in |
1369 | any way. The remote server CPU could be grinding to a halt |
1370 | and unresponsive to any clients connecting, but if the kernel |
1371 | throws the ACK packet, it is considered alive anyway. To |
1372 | really determine if the server is responding well would be |
1373 | application specific and is beyond the scope of Net::Ping. |
1374 | |
1375 | This only affects "tcp" and "syn" protocols. |
1376 | |
1377 | This is disabled by default. |
1378 | |
e82f584b |
1379 | =item $p->hires( { 0 | 1 } ); |
1380 | |
1381 | Causes this module to use Time::HiRes module, allowing milliseconds |
1382 | to be returned by subsequent calls to ping(). |
1383 | |
15d96390 |
1384 | This is disabled by default. |
1385 | |
49afa5f6 |
1386 | =item $p->bind($local_addr); |
1387 | |
1388 | Sets the source address from which pings will be sent. This must be |
1389 | the address of one of the interfaces on the local host. $local_addr |
1390 | may be specified as a hostname or as a text IP address such as |
1391 | "192.168.1.1". |
1392 | |
1393 | If the protocol is set to "tcp", this method may be called any |
1394 | number of times, and each call to the ping() method (below) will use |
1395 | the most recent $local_addr. If the protocol is "icmp" or "udp", |
1396 | then bind() must be called at most once per object, and (if it is |
1397 | called at all) must be called before the first call to ping() for that |
1398 | object. |
1399 | |
b124990b |
1400 | =item $p->open($host); |
1401 | |
f569508e |
1402 | When you are using the "stream" protocol, this call pre-opens the |
b124990b |
1403 | tcp socket. It's only necessary to do this if you want to |
1404 | provide a different timeout when creating the connection, or |
1405 | remove the overhead of establishing the connection from the |
1406 | first ping. If you don't call C<open()>, the connection is |
1407 | automatically opened the first time C<ping()> is called. |
787ecdfa |
1408 | This call simply does nothing if you are using any protocol other |
1409 | than stream. |
1410 | |
f569508e |
1411 | =item $p->ack( [ $host ] ); |
1412 | |
1413 | When using the "syn" protocol, use this method to determine |
1414 | the reachability of the remote host. This method is meant |
1415 | to be called up to as many times as ping() was called. Each |
1416 | call returns the host (as passed to ping()) that came back |
1417 | with the TCP ACK. The order in which the hosts are returned |
1418 | may not necessarily be the same order in which they were |
1419 | SYN queued using the ping() method. If the timeout is |
1420 | reached before the TCP ACK is received, or if the remote |
1421 | host is not listening on the port attempted, then the TCP |
1422 | connection will not be established and ack() will return |
1423 | undef. In list context, the host, the ack time, and the |
1424 | dotted ip string will be returned instead of just the host. |
1425 | If the optional $host argument is specified, the return |
1426 | value will be partaining to that host only. |
1427 | This call simply does nothing if you are using any protocol |
1428 | other than syn. |
1429 | |
1430 | =item $p->nack( $failed_ack_host ); |
1431 | |
1432 | The reason that host $failed_ack_host did not receive a |
1433 | valid ACK. Useful to find out why when ack( $fail_ack_host ) |
1434 | returns a false value. |
1435 | |
a3b93737 |
1436 | =item $p->close(); |
1437 | |
1438 | Close the network connection for this ping object. The network |
1439 | connection is also closed by "undef $p". The network connection is |
1440 | automatically closed if the ping object goes out of scope (e.g. $p is |
1441 | local to a subroutine and you leave the subroutine). |
1442 | |
1443 | =item pingecho($host [, $timeout]); |
1444 | |
1445 | To provide backward compatibility with the previous version of |
1446 | Net::Ping, a pingecho() subroutine is available with the same |
1447 | functionality as before. pingecho() uses the tcp protocol. The |
1448 | return values and parameters are the same as described for the ping() |
1449 | method. This subroutine is obsolete and may be removed in a future |
1450 | version of Net::Ping. |
8e07c86e |
1451 | |
a3b93737 |
1452 | =back |
8e07c86e |
1453 | |
a3b93737 |
1454 | =head1 NOTES |
8e07c86e |
1455 | |
a3b93737 |
1456 | There will be less network overhead (and some efficiency in your |
1457 | program) if you specify either the udp or the icmp protocol. The tcp |
1458 | protocol will generate 2.5 times or more traffic for each ping than |
1459 | either udp or icmp. If many hosts are pinged frequently, you may wish |
1460 | to implement a small wait (e.g. 25ms or more) between each ping to |
1461 | avoid flooding your network with packets. |
8e07c86e |
1462 | |
a3b93737 |
1463 | The icmp protocol requires that the program be run as root or that it |
787ecdfa |
1464 | be setuid to root. The other protocols do not require special |
1465 | privileges, but not all network devices implement tcp or udp echo. |
8e07c86e |
1466 | |
a3b93737 |
1467 | Local hosts should normally respond to pings within milliseconds. |
1468 | However, on a very congested network it may take up to 3 seconds or |
1469 | longer to receive an echo packet from the remote host. If the timeout |
1470 | is set too low under these conditions, it will appear that the remote |
1471 | host is not reachable (which is almost the truth). |
8e07c86e |
1472 | |
a3b93737 |
1473 | Reachability doesn't necessarily mean that the remote host is actually |
787ecdfa |
1474 | functioning beyond its ability to echo packets. tcp is slightly better |
1475 | at indicating the health of a system than icmp because it uses more |
1476 | of the networking stack to respond. |
8e07c86e |
1477 | |
a3b93737 |
1478 | Because of a lack of anything better, this module uses its own |
1479 | routines to pack and unpack ICMP packets. It would be better for a |
1480 | separate module to be written which understands all of the different |
1481 | kinds of ICMP packets. |
8e07c86e |
1482 | |
5d20095f |
1483 | =head1 INSTALL |
1484 | |
1485 | The latest source tree is available via cvs: |
1486 | |
f569508e |
1487 | cvs -z3 -q -d :pserver:anonymous@cvs.roobik.com.:/usr/local/cvsroot/freeware checkout Net-Ping |
5d20095f |
1488 | cd Net-Ping |
1489 | |
1490 | The tarball can be created as follows: |
1491 | |
1492 | perl Makefile.PL ; make ; make dist |
1493 | |
1494 | The latest Net::Ping release can be found at CPAN: |
1495 | |
1496 | $CPAN/modules/by-module/Net/ |
1497 | |
1498 | 1) Extract the tarball |
1499 | |
1500 | gtar -zxvf Net-Ping-xxxx.tar.gz |
1501 | cd Net-Ping-xxxx |
1502 | |
1503 | 2) Build: |
1504 | |
1505 | make realclean |
1506 | perl Makefile.PL |
1507 | make |
1508 | make test |
1509 | |
1510 | 3) Install |
1511 | |
1512 | make install |
1513 | |
1514 | Or install it RPM Style: |
1515 | |
1516 | rpm -ta SOURCES/Net-Ping-xxxx.tar.gz |
1517 | |
1518 | rpm -ih RPMS/noarch/perl-Net-Ping-xxxx.rpm |
1519 | |
49afa5f6 |
1520 | =head1 AUTHORS |
b124990b |
1521 | |
e82f584b |
1522 | Current maintainer: |
49afa5f6 |
1523 | bbb@cpan.org (Rob Brown) |
b124990b |
1524 | |
e82f584b |
1525 | External protocol: |
1526 | colinm@cpan.org (Colin McMillen) |
1527 | |
b124990b |
1528 | Stream protocol: |
1529 | bronson@trestle.com (Scott Bronson) |
1530 | |
1531 | Original pingecho(): |
1532 | karrer@bernina.ethz.ch (Andreas Karrer) |
1533 | pmarquess@bfsec.bt.co.uk (Paul Marquess) |
1534 | |
1535 | Original Net::Ping author: |
1536 | mose@ns.ccsn.edu (Russell Mosemann) |
1537 | |
b124990b |
1538 | =head1 COPYRIGHT |
1539 | |
9c36735d |
1540 | Copyright (c) 2002-2003, Rob Brown. All rights reserved. |
49afa5f6 |
1541 | |
e82f584b |
1542 | Copyright (c) 2001, Colin McMillen. All rights reserved. |
b124990b |
1543 | |
1544 | This program is free software; you may redistribute it and/or |
1545 | modify it under the same terms as Perl itself. |
1546 | |
a3b93737 |
1547 | =cut |