mdw@git.distorted.org.uk Git - odin-cgi/blob - lib/Odin.pm

   1 ### -*-perl-*-
   2
   3 package Odin;
   4
   5 use DBI;
   6 use Digest::SHA qw(sha256_hex);
   7 use MIME::Base64;
   8
   9 ###--------------------------------------------------------------------------
  10 ### Early utilities.
  11
  12 sub merge_hash (\%%) {
  13   my ($hashref, %defaults) = @_;
  14   for my $k (keys %defaults)
  15     { $hashref->{$k} = $defaults{$k} unless exists $hashref->{$k}; }
  16 }
  17
  18 ###--------------------------------------------------------------------------
  19 ### Configuration.
  20
  21 our $DSN = "dbi:Pg(pg_enable_utf8=>1):host=db";
  22 our $RETRY = 10;
  23 our @BACKOFF = (0.1, 10, 1.5, 0.5, 2.0);
  24
  25 our $BASEURL = "http://odin.gg/";
  26 our $STATIC = "http://odin.gg/";
  27
  28 our $SHORTURL_PATH = "u";
  29 our $PASTEBIN_PATH = "p";
  30
  31 our $URLMAXLEN = 1024;
  32 our @URLPAT = (
  33   qr{^https?://}
  34 );
  35
  36 our %COOKIE_DEFAULTS = (
  37   -httponly => undef,
  38   -max_age => 3600
  39 );
  40
  41 require "config.pl";
  42
  43 our ($SCHEME, $DOMAIN, $BASEPATH) = $BASEURL =~ m!^([^:]+)://([^/]+)(/.*)$!;
  44 merge_hash %COOKIE_DEFAULTS, -domain => $DOMAIN, -path => $BASEPATH;
  45 merge_hash %COOKIE_DEFAULTS, -secure => undef if $SCHEME eq "https";
  46
  47 our $SHORTURL = "$BASEURL$SHORTURL_PATH";
  48 our $PASTEBIN = "$BASEURL$PASTEBIN_PATH";
  49
  50 ###--------------------------------------------------------------------------
  51 ### Miscellaneous utilities.
  52
  53 our $NOW;
  54 sub update_now () { $NOW = time; }
  55 update_now;
  56
  57 (our $PROG = $0) =~ s:^.*/::;
  58
  59 sub fail_cmdline ($$%) {
  60   my ($msg, $label, %args) = @_;
  61   print STDERR "$PROG: $msg\n";
  62   exit 1;
  63 }
  64
  65 our $FAILPROC = \&fail_cmdline;
  66
  67 sub fail ($;$%) {
  68   my ($msg, $label, %args) = @_;
  69   $FAILPROC->($msg, $label, %args);
  70 }
  71
  72 sub set_mason_failproc ($) {
  73   my ($m) = @_;
  74   $FAILPROC = sub {
  75     my ($msg, $label, %args) = @_;
  76     $m->clear_buffer;
  77     $m->comp($label, %args);
  78     $m->abort;
  79   };
  80 }
  81
  82 sub nice_name ($) {
  83   my ($s) = @_;
  84   $s =~ s/\W+//g;
  85   return lc $s;
  86 }
  87
  88 ###--------------------------------------------------------------------------
  89 ### Database utilities.
  90
  91 sub open_db (@) {
  92   my @attr = @_;
  93   my $db = DBI->connect_cached($DSN, undef, undef, {
  94     PrintError => 0,
  95     RaiseError => 1,
  96     @attr
  97   });
  98
  99   my $drv = $db->{Driver}{Name};
 100   if ($drv eq "Pg") {
 101     $db->{private_odin_retry_p} = sub { $db->state =~ /^40[0P]01$/ };
 102   } elsif ($drv eq "SQLite") {
 103     $db->{private_odin_retry_p} = sub { $db->err == 5 };
 104   } else {
 105     $db->{private_odin_retry_p} = sub { 0 };
 106   }
 107
 108   return $db;
 109 }
 110
 111 sub xact (&$) {
 112   my ($body, $db) = @_;
 113   my @rv;
 114   my $exc;
 115
 116   my ($sleep, $maxsleep, $mult, $minvar, $maxvar) = @BACKOFF;
 117   for (my $i = 0; $i < $RETRY; $i++) {
 118     $db->begin_work;
 119     eval { @rv = $body->(); $db->commit; };
 120     $exc = $@;
 121     return @rv unless $exc;
 122     my $retryp = $db->{private_odin_retry_p}();
 123     eval { $db->rollback; };
 124     die $exc unless $retryp;
 125     my $t = $sleep * ($minvar + rand($maxvar - $minvar));
 126     $sleep *= $mult; $sleep = $max if $sleep > $max;
 127     select undef, undef, undef, $t;
 128   }
 129   die $exc;
 130 }
 131
 132
 133 ###--------------------------------------------------------------------------
 134 ### Sequence numbers and tagging.
 135
 136 sub next_seq ($$) {
 137   my ($db, $table) = @_;
 138   my ($seq) = $db->selectrow_array("SELECT seq FROM $table");
 139   die "no sequence number in $table" unless defined $seq;
 140   $db->do("UPDATE $table SET seq = ?", undef, $seq + 1);
 141   return $seq;
 142 }
 143
 144 my $ALPHABET =
 145   "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
 146 my $NALPHA = length $ALPHABET;
 147
 148 sub encode_tag ($) {
 149   my ($seq) = @_;
 150   my $tag = "";
 151   while ($seq) {
 152     $tag .= substr($ALPHABET, $seq % $NALPHA, 1);
 153     $seq = int $seq/$NALPHA;
 154   }
 155   return $tag;
 156 }
 157
 158 ###--------------------------------------------------------------------------
 159 ### HTTP utilities.
 160
 161 our %COOKIE;
 162 sub fetch_cookies ($) {
 163   my ($r) = @_;
 164
 165   %COOKIE = ();
 166   my $cookies = $r->header_in("Cookie");
 167   if (defined $cookies) {
 168     for my $kv (split /;/, $cookies) {
 169       my ($k, $v) = split /=/, $kv, 2;
 170       $k =~ s/^\s*(|\S|\S.*\S)\s*$/$1/;
 171       $v =~ s/^\s*(|\S|\S.*\S)\s*$/$1/;
 172       $v =~ s/\+/ /g;
 173       $v =~ s/\%([0-9a-f][0-9a-f])/chr hex $1/eg;
 174       $COOKIE{$k} = $v;
 175     }
 176   }
 177 }
 178
 179 sub bake_cookie ($$%) {
 180   my ($r, $cookie, %attr) = @_;
 181   merge_hash %attr, %COOKIE_DEFAULTS;
 182   my @attr = map {
 183     my $v = $attr{$_}; tr/_-/-/d;
 184     defined $v ? "$_=$v" : $_
 185   } keys %attr;
 186   $r->headers_out->add("Set-Cookie", join "; ", $cookie, @attr);
 187 }
 188
 189 sub path_info ($) {
 190   my ($r) = @_;
 191   return $ENV{PATH_INFO} // $r->path_info;
 192 }
 193
 194 ###--------------------------------------------------------------------------
 195 ### HTML utilities.
 196
 197 sub escapify ($$;$) {
 198   my ($m, $s, $mode) = @_;
 199   return $m->interp->apply_escapes($s, $mode // "h");
 200 }
 201
 202 ###--------------------------------------------------------------------------
 203 ### Access control.
 204
 205 our ($WHO, $WHOSURE);
 206 our ($WHOMATCH, $WHOCMP, $WHOPAT);
 207
 208 sub cgi_who ($) {
 209   my ($r) = @_;
 210   my $raddr = $ENV{REMOTE_ADDR} // $r->connection->remote_ip;
 211   $WHO = ":NET-$raddr"; $WHOSURE = 0;
 212   $WHOMATCH = "LIKE"; $WHOCMP = ":NET-\%"; $WHOPAT = qr/^:NET-/;
 213 }
 214
 215 sub cmdline_who () {
 216   $WHO = $ENV{USERV_USER}
 217     // ($< == $> && $ENV{USER})
 218     // @{[getpwuid $<]}[0]
 219     // die "nameless user";
 220   $WHOMATCH = "="; $WHOCMP = $WHO; $WHOPAT = qr/^\Q$WHO\E$/;
 221   $WHOSURE = 1;
 222 }
 223
 224 sub new_editkey () {
 225   open my $fh, "/dev/urandom" or die "open urandom: $!";
 226   sysread $fh, my $rand, 16;
 227   (my $edit = encode_base64 $rand) =~ tr:+/=\n:.-:d;
 228   return $edit, sha256_hex $edit;
 229 }
 230
 231 ###--------------------------------------------------------------------------
 232 ### URL shortening.
 233
 234 sub get_shorturl ($) {
 235   my ($tag) = @_;
 236
 237   my $db = open_db;
 238   my ($url) = $db->selectrow_array
 239     ("SELECT url FROM odin_shorturl WHERE tag = ?", undef, $tag);
 240   fail "tag `$tag' not found", ".notfound", tag => $tag unless defined $url;
 241   return $url;
 242 }
 243
 244 sub valid_url_p ($) {
 245   my ($url) = @_;
 246   return
 247     length $url < $URLMAXLEN &&
 248     scalar grep { $url =~ /$_/ } @URLPAT;
 249 }
 250
 251 sub new_shorturl ($) {
 252   my ($url) = @_;
 253
 254   valid_url_p $url or fail "invalid url", ".badurl", u => $url;
 255
 256   my $db = open_db;
 257   my $tag;
 258   xact {
 259     ($tag) = $db->selectrow_array
 260       ("SELECT tag FROM odin_shorturl WHERE owner $WHOMATCH ? AND url = ?",
 261        undef, $WHOCMP, $url);
 262     unless (defined $tag) {
 263       $tag = encode_tag(next_seq($db, "odin_shorturl_seq"));
 264       $db->do("INSERT INTO odin_shorturl (tag, stamp, owner, url)
 265                VALUES (?, ?, ?, ?)", undef,
 266               $tag, $NOW, $WHO, $url);
 267     }
 268   } $db;
 269   return $tag;
 270 }
 271
 272 sub check_shorturl_owner ($$) {
 273   my ($db, $tag) = @_;
 274
 275   my ($owner) = $db->selectrow_array
 276     ("SELECT owner FROM odin_shorturl WHERE tag = ?", undef, $tag);
 277   fail "tag `$tag' not found", ".notfound", tag => $tag
 278     unless defined $owner;
 279   fail "not owner of `$tag'", ".notowner", tag => $tag
 280     unless $owner =~ /$WHOPAT/;
 281 }
 282
 283 sub update_shorturl ($$) {
 284   my ($tag, $url) = @_;
 285
 286   my $db = open_db;
 287   xact {
 288     check_shorturl_owner $db, $tag;
 289     $db->do("UPDATE odin_shorturl SET url = ? WHERE tag = ?",
 290             undef, $url, $tag);
 291   } $db;
 292 }
 293
 294 sub delete_shorturl (@) {
 295   my (@tags) = @_;
 296
 297   my $db = open_db;
 298   xact {
 299     for my $tag (@tags) {
 300       check_shorturl_owner $db, $tag;
 301       $db->do("DELETE FROM odin_shorturl WHERE tag = ?", undef, $tag);
 302     }
 303   } $db;
 304 }
 305
 306 ###--------------------------------------------------------------------------
 307 ### Paste bin.
 308
 309 our %PASTEBIN_DEFAULTS = (
 310   title => "(untitled)",
 311   lang => "txt",
 312   content => ""
 313 );
 314 our @PASTEBIN_PROPS = keys %PASTEBIN_DEFAULTS;
 315 our $PASTEBIN_PROPCOLS = join ", ", @PASTEBIN_PROPS;
 316 our $PASTEBIN_PROPPLACES = join ", ", map "?", @PASTEBIN_PROPS;
 317
 318 sub new_pastebin (\%) {
 319   my ($new) = @_;
 320
 321   my $db = open_db;
 322   my ($editkey, $hash) = new_editkey;
 323   my $tag;
 324
 325   merge_hash %$new, %PASTEBIN_DEFAULTS;
 326   xact {
 327     $tag = encode_tag next_seq $db, "odin_pastebin_seq";
 328     $db->do("INSERT INTO odin_pastebin
 329                (tag, stamp, edithash, owner, $PASTEBIN_PROPCOLS)
 330              VALUES (?, ?, ?, ?, $PASTEBIN_PROPPLACES)", undef,
 331             $tag, $NOW, $hash, $WHO, @{$new}{@PASTEBIN_PROPS});
 332   } $db;
 333   return $tag, $editkey;
 334 }
 335
 336 sub get_pastebin ($$\%) {
 337   my ($db, $tag, $props) = @_;
 338
 339   (my $owner, my $hash, @{$props}{@PASTEBIN_PROPS}) =
 340     $db->selectrow_array("SELECT owner, edithash, $PASTEBIN_PROPCOLS
 341                           FROM odin_pastebin WHERE tag = ?",
 342                          undef, $tag);
 343   fail "tag `$tag' not found", ".notfound", tag => $tag
 344     unless defined $owner;
 345   return $owner, $hash;
 346 }
 347
 348 sub get_pastebin_check_owner ($$\%) {
 349   my ($db, $tag, $props) = @_;
 350
 351   my ($owner, $hash) = get_pastebin $db, $tag, %$props;
 352   fail "not owner of `$tag'", ".notowner", tag => $tag
 353     unless $WHOSURE && $WHO eq $owner;
 354 }
 355
 356 sub get_pastebin_check_editkey_or_owner ($$$\%) {
 357   my ($db, $tag, $editkey, $props) = @_;
 358
 359   if (!defined $editkey) { get_pastebin_check_owner $db, $tag, %$props; }
 360   else {
 361     my ($owner, $hash) = get_pastebin $db, $tag, %$props;
 362     fail "incorrect edit key for `$tag'", ".badhash", tag => $tag
 363       unless $hash eq sha256_hex $editkey;
 364   }
 365 }
 366
 367 sub rekey_pastebin ($) {
 368   my ($tag) = @_;
 369
 370   my $db = open_db;
 371   my $editkey;
 372   xact {
 373     get_pastebin_check_owner $db, $tag, my %hunoz;
 374     ($editkey, my $hash) = new_editkey;
 375     $db->do("UPDATE odin_pastebin SET edithash = ? WHERE tag = ?",
 376             undef, $hash, $tag);
 377   } $db;
 378   return $editkey;
 379 }
 380
 381 sub claim_pastebin ($$) {
 382   my ($tag, $editkey) = @_;
 383
 384   my $db = open_db;
 385   $WHOSURE or fail "you can't claim pastes", ".notsure";
 386   xact {
 387     get_pastebin_check_editkey_or_owner $db, $tag, $editkey, my %hunoz;
 388     $db->do("UPDATE odin_pastebin SET owner = ? WHERE tag = ?",
 389             undef, $WHO, $tag);
 390   } $db;
 391 }
 392
 393 sub update_pastebin ($$\%) {
 394   my ($tag, $editkey, $new) = @_;
 395
 396   my $db = open_db;
 397   my $editp = 0;
 398   xact {
 399     get_pastebin_check_editkey_or_owner $db, $tag, $editkey, my %old;
 400     for my $p (@PASTEBIN_PROPS) {
 401       if (!defined $new->{$p}) { $new->{$p} = $old{$p}; }
 402       else {
 403         $db->do("UPDATE odin_pastebin SET $p = ? WHERE tag = ?",
 404                 undef, $new->{$p}, $tag)
 405           unless $new->{$p} eq $old{$p};
 406         $editp = 1;
 407       }
 408     }
 409   } $db;
 410   return $editp;
 411 }
 412
 413 sub delete_pastebin (@) {
 414   my @a = @_;
 415   my $db = open_db;
 416   xact {
 417     while (@a) {
 418       (my $tag, my $editkey, @a) = @a;
 419       get_pastebin_check_editkey_or_owner $db, $tag, $editkey, my %hunoz;
 420       $db->do("DELETE FROM odin_pastebin WHERE tag = ?", undef, $tag);
 421     }
 422   } $db;
 423 }
 424
 425 sub tidy_pastebin_content ($) {
 426   my ($content) = @_;
 427   return undef unless defined $content;
 428   $content =~ tr/\r//d;
 429   $content =~ s/([^\n])\z/$1\n/;
 430   return $content;
 431 }
 432
 433 ###--------------------------------------------------------------------------
 434 ### Simple option parser.
 435
 436 package Odin::OptParse;
 437
 438 sub new {
 439   my ($cls, @args) = @_;
 440   return bless {
 441     cur => "",
 442     args => \@args,
 443     opt => undef,
 444     ok => 1
 445   }, $cls;
 446 }
 447
 448 sub get {
 449   my ($me) = @_;
 450   if (!length $me->{cur}) {
 451     my $args = $me->{args};
 452     if (!@$args) { return undef; }
 453     elsif ($args->[0] =~ /^[^-]|^-$/) { return undef; }
 454     elsif ($args->[0] eq "--") { shift @$args; return undef; }
 455     $me->{cur} = substr shift @$args, 1;
 456   }
 457   my $o = $me->{opt} = substr $me->{cur}, 0, 1;
 458   $me->{cur} = substr $me->{cur}, 1;
 459   return $o;
 460 }
 461
 462 sub arg {
 463   my ($me) = @_;
 464   my $a;
 465   if (length $me->{cur}) { $a = $me->{cur}; $me->{cur} = ""; }
 466   elsif (@{$me->{args}}) { $a = shift @{$me->{args}}; }
 467   else { $a = undef; $me->err("option `-$me->{opt}' requires an argument"); }
 468   return $a;
 469 }
 470
 471 sub rest { return @{$_[0]->{args}}; }
 472 sub ok { return $_[0]->{ok}; }
 473 sub bad { $_[0]->{ok} = 0; }
 474 sub err { $_[0]->bad; print STDERR "$PROG: $_[1]\n"; }
 475 sub unk { $_[0]->err("unknown option `-$_[0]->{opt}'"); }
 476
 477 ###----- That's all, folks --------------------------------------------------
 478
 479 1;