Merge branch 'js/rebase-reschedule-applies-only-to-interactive' into maint
[git/git.git] / contrib / hooks / update-paranoid
1 #!/usr/bin/perl
2
3 use strict;
4 use File::Spec;
5
6 $ENV{PATH} = '/opt/git/bin';
7 my $acl_git = '/vcs/acls.git';
8 my $acl_branch = 'refs/heads/master';
9 my $debug = 0;
10
11 =doc
12 Invoked as: update refname old-sha1 new-sha1
13
14 This script is run by git-receive-pack once for each ref that the
15 client is trying to modify. If we exit with a non-zero exit value
16 then the update for that particular ref is denied, but updates for
17 other refs in the same run of receive-pack may still be allowed.
18
19 We are run after the objects have been uploaded, but before the
20 ref is actually modified. We take advantage of that fact when we
21 look for "new" commits and tags (the new objects won't show up in
22 `rev-list --all`).
23
24 This script loads and parses the content of the config file
25 "users/$this_user.acl" from the $acl_branch commit of $acl_git ODB.
26 The acl file is a git-config style file, but uses a slightly more
27 restricted syntax as the Perl parser contained within this script
28 is not nearly as permissive as git-config.
29
30 Example:
31
32 [user]
33 committer = John Doe <john.doe@example.com>
34 committer = John R. Doe <john.doe@example.com>
35
36 [repository "acls"]
37 allow = heads/master
38 allow = CDUR for heads/jd/
39 allow = C for ^tags/v\\d+$
40
41 For all new commit or tag objects the committer (or tagger) line
42 within the object must exactly match one of the user.committer
43 values listed in the acl file ("HEAD:users/$this_user.acl").
44
45 For a branch to be modified an allow line within the matching
46 repository section must be matched for both the refname and the
47 opcode.
48
49 Repository sections are matched on the basename of the repository
50 (after removing the .git suffix).
51
52 The opcode abbrevations are:
53
54 C: create new ref
55 D: delete existing ref
56 U: fast-forward existing ref (no commit loss)
57 R: rewind/rebase existing ref (commit loss)
58
59 if no opcodes are listed before the "for" keyword then "U" (for
60 fast-forward update only) is assumed as this is the most common
61 usage.
62
63 Refnames are matched by always assuming a prefix of "refs/".
64 This hook forbids pushing or deleting anything not under "refs/".
65
66 Refnames that start with ^ are Perl regular expressions, and the ^
67 is kept as part of the regexp. \\ is needed to get just one \, so
68 \\d expands to \d in Perl. The 3rd allow line above is an example.
69
70 Refnames that don't start with ^ but that end with / are prefix
71 matches (2nd allow line above); all other refnames are strict
72 equality matches (1st allow line).
73
74 Anything pushed to "heads/" (ok, really "refs/heads/") must be
75 a commit. Tags are not permitted here.
76
77 Anything pushed to "tags/" (err, really "refs/tags/") must be an
78 annotated tag. Commits, blobs, trees, etc. are not permitted here.
79 Annotated tag signatures aren't checked, nor are they required.
80
81 The special subrepository of 'info/new-commit-check' can
82 be created and used to allow users to push new commits and
83 tags from another local repository to this one, even if they
84 aren't the committer/tagger of those objects. In a nut shell
85 the info/new-commit-check directory is a Git repository whose
86 objects/info/alternates file lists this repository and all other
87 possible sources, and whose refs subdirectory contains symlinks
88 to this repository's refs subdirectory, and to all other possible
89 sources refs subdirectories. Yes, this means that you cannot
90 use packed-refs in those repositories as they won't be resolved
91 correctly.
92
93 =cut
94
95 my $git_dir = $ENV{GIT_DIR};
96 my $new_commit_check = "$git_dir/info/new-commit-check";
97 my $ref = $ARGV[0];
98 my $old = $ARGV[1];
99 my $new = $ARGV[2];
100 my $new_type;
101 my ($this_user) = getpwuid $<; # REAL_USER_ID
102 my $repository_name;
103 my %user_committer;
104 my @allow_rules;
105 my @path_rules;
106 my %diff_cache;
107
108 sub deny ($) {
109 print STDERR "-Deny- $_[0]\n" if $debug;
110 print STDERR "\ndenied: $_[0]\n\n";
111 exit 1;
112 }
113
114 sub grant ($) {
115 print STDERR "-Grant- $_[0]\n" if $debug;
116 exit 0;
117 }
118
119 sub info ($) {
120 print STDERR "-Info- $_[0]\n" if $debug;
121 }
122
123 sub git_value (@) {
124 open(T,'-|','git',@_); local $_ = <T>; chop; close T; $_;
125 }
126
127 sub match_string ($$) {
128 my ($acl_n, $ref) = @_;
129 ($acl_n eq $ref)
130 || ($acl_n =~ m,/$, && substr($ref,0,length $acl_n) eq $acl_n)
131 || ($acl_n =~ m,^\^, && $ref =~ m:$acl_n:);
132 }
133
134 sub parse_config ($$$$) {
135 my $data = shift;
136 local $ENV{GIT_DIR} = shift;
137 my $br = shift;
138 my $fn = shift;
139 return unless git_value('rev-list','--max-count=1',$br,'--',$fn);
140 info "Loading $br:$fn";
141 open(I,'-|','git','cat-file','blob',"$br:$fn");
142 my $section = '';
143 while (<I>) {
144 chomp;
145 if (/^\s*$/ || /^\s*#/) {
146 } elsif (/^\[([a-z]+)\]$/i) {
147 $section = lc $1;
148 } elsif (/^\[([a-z]+)\s+"(.*)"\]$/i) {
149 $section = join('.',lc $1,$2);
150 } elsif (/^\s*([a-z][a-z0-9]+)\s*=\s*(.*?)\s*$/i) {
151 push @{$data->{join('.',$section,lc $1)}}, $2;
152 } else {
153 deny "bad config file line $. in $br:$fn";
154 }
155 }
156 close I;
157 }
158
159 sub all_new_committers () {
160 local $ENV{GIT_DIR} = $git_dir;
161 $ENV{GIT_DIR} = $new_commit_check if -d $new_commit_check;
162
163 info "Getting committers of new commits.";
164 my %used;
165 open(T,'-|','git','rev-list','--pretty=raw',$new,'--not','--all');
166 while (<T>) {
167 next unless s/^committer //;
168 chop;
169 s/>.*$/>/;
170 info "Found $_." unless $used{$_}++;
171 }
172 close T;
173 info "No new commits." unless %used;
174 keys %used;
175 }
176
177 sub all_new_taggers () {
178 my %exists;
179 open(T,'-|','git','for-each-ref','--format=%(objectname)','refs/tags');
180 while (<T>) {
181 chop;
182 $exists{$_} = 1;
183 }
184 close T;
185
186 info "Getting taggers of new tags.";
187 my %used;
188 my $obj = $new;
189 my $obj_type = $new_type;
190 while ($obj_type eq 'tag') {
191 last if $exists{$obj};
192 $obj_type = '';
193 open(T,'-|','git','cat-file','tag',$obj);
194 while (<T>) {
195 chop;
196 if (/^object ([a-z0-9]{40})$/) {
197 $obj = $1;
198 } elsif (/^type (.+)$/) {
199 $obj_type = $1;
200 } elsif (s/^tagger //) {
201 s/>.*$/>/;
202 info "Found $_." unless $used{$_}++;
203 last;
204 }
205 }
206 close T;
207 }
208 info "No new tags." unless %used;
209 keys %used;
210 }
211
212 sub check_committers (@) {
213 my @bad;
214 foreach (@_) { push @bad, $_ unless $user_committer{$_}; }
215 if (@bad) {
216 print STDERR "\n";
217 print STDERR "You are not $_.\n" foreach (sort @bad);
218 deny "You cannot push changes not committed by you.";
219 }
220 }
221
222 sub load_diff ($) {
223 my $base = shift;
224 my $d = $diff_cache{$base};
225 unless ($d) {
226 local $/ = "\0";
227 my %this_diff;
228 if ($base =~ /^0{40}$/) {
229 # Don't load the diff at all; we are making the
230 # branch and have no base to compare to in this
231 # case. A file level ACL makes no sense in this
232 # context. Having an empty diff will allow the
233 # branch creation.
234 #
235 } else {
236 open(T,'-|','git','diff-tree',
237 '-r','--name-status','-z',
238 $base,$new) or return undef;
239 while (<T>) {
240 my $op = $_;
241 chop $op;
242
243 my $path = <T>;
244 chop $path;
245
246 $this_diff{$path} = $op;
247 }
248 close T or return undef;
249 }
250 $d = \%this_diff;
251 $diff_cache{$base} = $d;
252 }
253 return $d;
254 }
255
256 deny "No GIT_DIR inherited from caller" unless $git_dir;
257 deny "Need a ref name" unless $ref;
258 deny "Refusing funny ref $ref" unless $ref =~ s,^refs/,,;
259 deny "Bad old value $old" unless $old =~ /^[a-z0-9]{40}$/;
260 deny "Bad new value $new" unless $new =~ /^[a-z0-9]{40}$/;
261 deny "Cannot determine who you are." unless $this_user;
262 grant "No change requested." if $old eq $new;
263
264 $repository_name = File::Spec->rel2abs($git_dir);
265 $repository_name =~ m,/([^/]+)(?:\.git|/\.git)$,;
266 $repository_name = $1;
267 info "Updating in '$repository_name'.";
268
269 my $op;
270 if ($old =~ /^0{40}$/) { $op = 'C'; }
271 elsif ($new =~ /^0{40}$/) { $op = 'D'; }
272 else { $op = 'R'; }
273
274 # This is really an update (fast-forward) if the
275 # merge base of $old and $new is $old.
276 #
277 $op = 'U' if ($op eq 'R'
278 && $ref =~ m,^heads/,
279 && $old eq git_value('merge-base',$old,$new));
280
281 # Load the user's ACL file. Expand groups (user.memberof) one level.
282 {
283 my %data = ('user.committer' => []);
284 parse_config(\%data,$acl_git,$acl_branch,"external/$repository_name.acl");
285
286 %data = (
287 'user.committer' => $data{'user.committer'},
288 'user.memberof' => [],
289 );
290 parse_config(\%data,$acl_git,$acl_branch,"users/$this_user.acl");
291
292 %user_committer = map {$_ => $_} @{$data{'user.committer'}};
293 my $rule_key = "repository.$repository_name.allow";
294 my $rules = $data{$rule_key} || [];
295
296 foreach my $group (@{$data{'user.memberof'}}) {
297 my %g;
298 parse_config(\%g,$acl_git,$acl_branch,"groups/$group.acl");
299 my $group_rules = $g{$rule_key};
300 push @$rules, @$group_rules if $group_rules;
301 }
302
303 RULE:
304 foreach (@$rules) {
305 while (/\${user\.([a-z][a-zA-Z0-9]+)}/) {
306 my $k = lc $1;
307 my $v = $data{"user.$k"};
308 next RULE unless defined $v;
309 next RULE if @$v != 1;
310 next RULE unless defined $v->[0];
311 s/\${user\.$k}/$v->[0]/g;
312 }
313
314 if (/^([AMD ]+)\s+of\s+([^\s]+)\s+for\s+([^\s]+)\s+diff\s+([^\s]+)$/) {
315 my ($ops, $pth, $ref, $bst) = ($1, $2, $3, $4);
316 $ops =~ s/ //g;
317 $pth =~ s/\\\\/\\/g;
318 $ref =~ s/\\\\/\\/g;
319 push @path_rules, [$ops, $pth, $ref, $bst];
320 } elsif (/^([AMD ]+)\s+of\s+([^\s]+)\s+for\s+([^\s]+)$/) {
321 my ($ops, $pth, $ref) = ($1, $2, $3);
322 $ops =~ s/ //g;
323 $pth =~ s/\\\\/\\/g;
324 $ref =~ s/\\\\/\\/g;
325 push @path_rules, [$ops, $pth, $ref, $old];
326 } elsif (/^([CDRU ]+)\s+for\s+([^\s]+)$/) {
327 my $ops = $1;
328 my $ref = $2;
329 $ops =~ s/ //g;
330 $ref =~ s/\\\\/\\/g;
331 push @allow_rules, [$ops, $ref];
332 } elsif (/^for\s+([^\s]+)$/) {
333 # Mentioned, but nothing granted?
334 } elsif (/^[^\s]+$/) {
335 s/\\\\/\\/g;
336 push @allow_rules, ['U', $_];
337 }
338 }
339 }
340
341 if ($op ne 'D') {
342 $new_type = git_value('cat-file','-t',$new);
343
344 if ($ref =~ m,^heads/,) {
345 deny "$ref must be a commit." unless $new_type eq 'commit';
346 } elsif ($ref =~ m,^tags/,) {
347 deny "$ref must be an annotated tag." unless $new_type eq 'tag';
348 }
349
350 check_committers (all_new_committers);
351 check_committers (all_new_taggers) if $new_type eq 'tag';
352 }
353
354 info "$this_user wants $op for $ref";
355 foreach my $acl_entry (@allow_rules) {
356 my ($acl_ops, $acl_n) = @$acl_entry;
357 next unless $acl_ops =~ /^[CDRU]+$/; # Uhh.... shouldn't happen.
358 next unless $acl_n;
359 next unless $op =~ /^[$acl_ops]$/;
360 next unless match_string $acl_n, $ref;
361
362 # Don't test path rules on branch deletes.
363 #
364 grant "Allowed by: $acl_ops for $acl_n" if $op eq 'D';
365
366 # Aggregate matching path rules; allow if there aren't
367 # any matching this ref.
368 #
369 my %pr;
370 foreach my $p_entry (@path_rules) {
371 my ($p_ops, $p_n, $p_ref, $p_bst) = @$p_entry;
372 next unless $p_ref;
373 push @{$pr{$p_bst}}, $p_entry if match_string $p_ref, $ref;
374 }
375 grant "Allowed by: $acl_ops for $acl_n" unless %pr;
376
377 # Allow only if all changes against a single base are
378 # allowed by file path rules.
379 #
380 my @bad;
381 foreach my $p_bst (keys %pr) {
382 my $diff_ref = load_diff $p_bst;
383 deny "Cannot difference trees." unless ref $diff_ref;
384
385 my %fd = %$diff_ref;
386 foreach my $p_entry (@{$pr{$p_bst}}) {
387 my ($p_ops, $p_n, $p_ref, $p_bst) = @$p_entry;
388 next unless $p_ops =~ /^[AMD]+$/;
389 next unless $p_n;
390
391 foreach my $f_n (keys %fd) {
392 my $f_op = $fd{$f_n};
393 next unless $f_op;
394 next unless $f_op =~ /^[$p_ops]$/;
395 delete $fd{$f_n} if match_string $p_n, $f_n;
396 }
397 last unless %fd;
398 }
399
400 if (%fd) {
401 push @bad, [$p_bst, \%fd];
402 } else {
403 # All changes relative to $p_bst were allowed.
404 #
405 grant "Allowed by: $acl_ops for $acl_n diff $p_bst";
406 }
407 }
408
409 foreach my $bad_ref (@bad) {
410 my ($p_bst, $fd) = @$bad_ref;
411 print STDERR "\n";
412 print STDERR "Not allowed to make the following changes:\n";
413 print STDERR "(base: $p_bst)\n";
414 foreach my $f_n (sort keys %$fd) {
415 print STDERR " $fd->{$f_n} $f_n\n";
416 }
417 }
418 deny "You are not permitted to $op $ref";
419 }
420 close A;
421 deny "You are not permitted to $op $ref";