1 /* Copyright 2008 Rob Landley <rob@landley.net>
2  *
3  * See http://opengroup.org/onlinepubs/9699919799/utilities/cp.html
4  * And http://opengroup.org/onlinepubs/9699919799/utilities/mv.html
5  * And http://refspecs.linuxfoundation.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic.html#INSTALL
6  *
7  * Posix says "cp -Rf dir file" shouldn't delete file, but our -f does.
8  *
9  * TODO: --preserve=links
10  * TODO: what's this _CP_mode system.posix_acl_ business? We chmod()?
11 
12 // options shared between mv/cp must be in same order (right to left)
13 // for FLAG macros to work out right in shared infrastructure.
14 
15 USE_CP(NEWTOY(cp, "<2"USE_CP_PRESERVE("(preserve):;")"RHLPp"USE_CP_MORE("rdaslvnF(remove-destination)")"fi[-HLP"USE_CP_MORE("d")"]"USE_CP_MORE("[-ni]"), TOYFLAG_BIN))
16 USE_MV(NEWTOY(mv, "<2"USE_CP_MORE("vnF")"fi"USE_CP_MORE("[-ni]"), TOYFLAG_BIN))
17 USE_INSTALL(NEWTOY(install, "<1cdDpsvm:o:g:", TOYFLAG_USR|TOYFLAG_BIN))
18 
19 config CP
20   bool "cp"
21   default y
22   help
23     usage: cp [-fipRHLP] SOURCE... DEST
24 
25     Copy files from SOURCE to DEST.  If more than one SOURCE, DEST must
26     be a directory.
27 
28     -f	delete destination files we can't write to
29     -F	delete any existing destination file first (--remove-destination)
30     -i	interactive, prompt before overwriting existing DEST
31     -p	preserve timestamps, ownership, and mode
32     -R	recurse into subdirectories (DEST must be a directory)
33     -H	Follow symlinks listed on command line
34     -L	Follow all symlinks
35     -P	Do not follow symlinks [default]
36 
37 config CP_MORE
38   bool "cp -adlnrsv options"
39   default y
40   depends on CP
41   help
42     usage: cp [-adlnrsv]
43 
44     -a	same as -dpr
45     -d	don't dereference symlinks
46     -l	hard link instead of copy
47     -n	no clobber (don't overwrite DEST)
48     -r	synonym for -R
49     -s	symlink instead of copy
50     -v	verbose
51 
52 config CP_PRESERVE
53   bool "cp --preserve support"
54   default y
55   depends on CP_MORE
56   help
57     usage: cp [--preserve=motcxa]
58 
59     --preserve takes either a comma separated list of attributes, or the first
60     letter(s) of:
61 
62             mode - permissions (ignore umask for rwx, copy suid and sticky bit)
63        ownership - user and group
64       timestamps - file creation, modification, and access times.
65          context - security context
66            xattr - extended attributes
67              all - all of the above
68 
69 config MV
70   bool "mv"
71   default y
72   depends on CP
73   help
74     usage: mv [-fi] SOURCE... DEST"
75 
76     -f	force copy by deleting destination file
77     -i	interactive, prompt before overwriting existing DEST
78 
79 config MV_MORE
80   bool
81   default y
82   depends on MV && CP_MORE
83   help
84     usage: mv [-vn]
85 
86     -v	verbose
87     -n	no clobber (don't overwrite DEST)
88 
89 config INSTALL
90   bool "install"
91   default y
92   depends on CP && CP_MORE
93   help
94     usage: install [-dDpsv] [-o USER] [-g GROUP] [-m MODE] [SOURCE...] DEST
95 
96     Copy files and set attributes.
97 
98     -d	Act like mkdir -p
99     -D	Create leading directories for DEST
100     -g	Make copy belong to GROUP
101     -m	Set permissions to MODE
102     -o	Make copy belong to USER
103     -p	Preserve timestamps
104     -s	Call "strip -p"
105     -v	Verbose
106 */
107 
108 #define FOR_cp
109 #include "toys.h"
110 #if CFG_CP_PRESERVE
111 #include <sys/xattr.h>
112 #endif
113 
114 GLOBALS(
115   union {
116     struct {
117       // install's options
118       char *group;
119       char *user;
120       char *mode;
121     } i;
122     struct {
123       char *preserve;
124     } c;
125   };
126 
127   char *destname;
128   struct stat top;
129   int (*callback)(struct dirtree *try);
130   uid_t uid;
131   gid_t gid;
132   int pflags;
133 )
134 
135 struct cp_preserve {
136   char *name;
137 } static const cp_preserve[] = TAGGED_ARRAY(CP,
138   {"mode"}, {"ownership"}, {"timestamps"}, {"context"}, {"xattr"},
139 );
140 
141 // Callback from dirtree_read() for each file/directory under a source dir.
142 
cp_node(struct dirtree * try)143 int cp_node(struct dirtree *try)
144 {
145   int fdout = -1, cfd = try->parent ? try->parent->extra : AT_FDCWD,
146       tfd = dirtree_parentfd(try);
147   unsigned flags = toys.optflags;
148   char *catch = try->parent ? try->name : TT.destname, *err = "%s";
149   struct stat cst;
150 
151   if (!dirtree_notdotdot(try)) return 0;
152 
153   // If returning from COMEAGAIN, jump straight to -p logic at end.
154   if (S_ISDIR(try->st.st_mode) && try->again) {
155     fdout = try->extra;
156     err = 0;
157   } else {
158 
159     // -d is only the same as -r for symlinks, not for directories
160     if (S_ISLNK(try->st.st_mode) && (flags & FLAG_d)) flags |= FLAG_r;
161 
162     // Detect recursive copies via repeated top node (cp -R .. .) or
163     // identical source/target (fun with hardlinks).
164     if ((TT.top.st_dev == try->st.st_dev && TT.top.st_ino == try->st.st_ino
165          && (catch = TT.destname))
166         || (!fstatat(cfd, catch, &cst, 0) && cst.st_dev == try->st.st_dev
167          && cst.st_ino == try->st.st_ino))
168     {
169       error_msg("'%s' is '%s'", catch, err = dirtree_path(try, 0));
170       free(err);
171 
172       return 0;
173     }
174 
175     // Handle -inv
176 
177     if (!faccessat(cfd, catch, F_OK, 0) && !S_ISDIR(cst.st_mode)) {
178       char *s;
179 
180       if (S_ISDIR(try->st.st_mode)) {
181         error_msg("dir at '%s'", s = dirtree_path(try, 0));
182         free(s);
183         return 0;
184       } else if ((flags & FLAG_F) && unlinkat(cfd, catch, 0)) {
185         error_msg("unlink '%s'", catch);
186         return 0;
187       } else if (flags & FLAG_n) return 0;
188       else if (flags & FLAG_i) {
189         fprintf(stderr, "%s: overwrite '%s'", toys.which->name,
190           s = dirtree_path(try, 0));
191         free(s);
192         if (!yesno(1)) return 0;
193       }
194     }
195 
196     if (flags & FLAG_v) {
197       char *s = dirtree_path(try, 0);
198       printf("%s '%s'\n", toys.which->name, s);
199       free(s);
200     }
201 
202     // Loop for -f retry after unlink
203     do {
204 
205       // directory, hardlink, symlink, mknod (char, block, fifo, socket), file
206 
207       // Copy directory
208 
209       if (S_ISDIR(try->st.st_mode)) {
210         struct stat st2;
211 
212         if (!(flags & (FLAG_a|FLAG_r|FLAG_R))) {
213           err = "Skipped dir '%s'";
214           catch = try->name;
215           break;
216         }
217 
218         // Always make directory writeable to us, so we can create files in it.
219         //
220         // Yes, there's a race window between mkdir() and open() so it's
221         // possible that -p can be made to chown a directory other than the one
222         // we created. The closest we can do to closing this is make sure
223         // that what we open _is_ a directory rather than something else.
224 
225         if (!mkdirat(cfd, catch, try->st.st_mode | 0200) || errno == EEXIST)
226           if (-1 != (try->extra = openat(cfd, catch, O_NOFOLLOW)))
227             if (!fstat(try->extra, &st2) && S_ISDIR(st2.st_mode))
228               return DIRTREE_COMEAGAIN
229                      | (DIRTREE_SYMFOLLOW*!!(toys.optflags&FLAG_L));
230 
231       // Hardlink
232 
233       } else if (flags & FLAG_l) {
234         if (!linkat(tfd, try->name, cfd, catch, 0)) err = 0;
235 
236       // Copy tree as symlinks. For non-absolute paths this involves
237       // appending the right number of .. entries as you go down the tree.
238 
239       } else if (flags & FLAG_s) {
240         char *s;
241         struct dirtree *or;
242         int dotdots = 0;
243 
244         s = dirtree_path(try, 0);
245         for (or = try; or->parent; or = or->parent) dotdots++;
246 
247         if (*or->name == '/') dotdots = 0;
248         if (dotdots) {
249           char *s2 = xmprintf("%*c%s", 3*dotdots, ' ', s);
250           free(s);
251           s = s2;
252           while(dotdots--) {
253             memcpy(s2, "../", 3);
254             s2 += 3;
255           }
256         }
257         if (!symlinkat(s, cfd, catch)) {
258           err = 0;
259           fdout = AT_FDCWD;
260         }
261         free(s);
262 
263       // Do something _other_ than copy contents of a file?
264       } else if (!S_ISREG(try->st.st_mode)
265                  && (try->parent || (flags & (FLAG_a|FLAG_r))))
266       {
267         int i;
268 
269         // make symlink, or make block/char/fifo/socket
270         if (S_ISLNK(try->st.st_mode)
271             ? (0 < (i = readlinkat(tfd, try->name, toybuf, sizeof(toybuf))) &&
272                sizeof(toybuf) > i && !symlinkat(toybuf, cfd, catch))
273             : !mknodat(cfd, catch, try->st.st_mode, try->st.st_rdev))
274         {
275           err = 0;
276           fdout = AT_FDCWD;
277         }
278 
279       // Copy contents of file.
280       } else {
281         int fdin;
282 
283         fdin = openat(tfd, try->name, O_RDONLY);
284         if (fdin < 0) {
285           catch = try->name;
286           break;
287         }
288         fdout = openat(cfd, catch, O_RDWR|O_CREAT|O_TRUNC, try->st.st_mode);
289         if (fdout >= 0) {
290           xsendfile(fdin, fdout);
291           err = 0;
292         }
293 
294         // We only copy xattrs for files because there's no flistxattrat()
295         if (TT.pflags&(_CP_xattr|_CP_context)) {
296           ssize_t listlen = flistxattr(fdin, 0, 0), len;
297           char *name, *value, *list;
298 
299           if (listlen>0) {
300             list = xmalloc(listlen);
301             flistxattr(fdin, list, listlen);
302             list[listlen-1] = 0; // I do not trust this API.
303             for (name = list; name-list < listlen; name += strlen(name)+1) {
304               if (!(TT.pflags&_CP_xattr) && strncmp(name, "security.", 9))
305                 continue;
306               if ((len = fgetxattr(fdin, name, 0, 0))>0) {
307                 value = xmalloc(len);
308                 if (len == fgetxattr(fdin, name, value, len))
309                   if (fsetxattr(fdout, name, value, len, 0))
310                     perror_msg("%s setxattr(%s=%s)", catch, name, value);
311                 free(value);
312               }
313             }
314             free(list);
315           }
316         }
317 
318         close(fdin);
319       }
320     } while (err && (flags & (FLAG_f|FLAG_n)) && !unlinkat(cfd, catch, 0));
321   }
322 
323   // Did we make a thing?
324   if (fdout != -1) {
325     int rc;
326 
327     // Inability to set --preserve isn't fatal, some require root access.
328 
329     // ownership
330     if (TT.pflags & _CP_ownership) {
331 
332       // permission bits already correct for mknod and don't apply to symlink
333       // If we can't get a filehandle to the actual object, use racy functions
334       if (fdout == AT_FDCWD)
335         rc = fchownat(cfd, catch, try->st.st_uid, try->st.st_gid,
336                       AT_SYMLINK_NOFOLLOW);
337       else rc = fchown(fdout, try->st.st_uid, try->st.st_gid);
338       if (rc) {
339         char *pp;
340 
341         perror_msg("chown '%s'", pp = dirtree_path(try, 0));
342         free(pp);
343       }
344     }
345 
346     // timestamp
347     if (TT.pflags & _CP_timestamps) {
348       struct timespec times[] = {try->st.st_atim, try->st.st_mtim};
349 
350       if (fdout == AT_FDCWD) utimensat(cfd, catch, times, AT_SYMLINK_NOFOLLOW);
351       else futimens(fdout, times);
352     }
353 
354     // mode comes last because other syscalls can strip suid bit
355     if (fdout != AT_FDCWD) {
356       if (TT.pflags & _CP_mode) fchmod(fdout, try->st.st_mode);
357       xclose(fdout);
358     }
359 
360     if (CFG_MV && toys.which->name[0] == 'm')
361       if (unlinkat(tfd, try->name, S_ISDIR(try->st.st_mode) ? AT_REMOVEDIR :0))
362         err = "%s";
363   }
364 
365   if (err) perror_msg(err, catch);
366   return 0;
367 }
368 
cp_main(void)369 void cp_main(void)
370 {
371   char *destname = toys.optargs[--toys.optc];
372   int i, destdir = !stat(destname, &TT.top) && S_ISDIR(TT.top.st_mode);
373 
374   if (toys.optc>1 && !destdir) error_exit("'%s' not directory", destname);
375 
376   if (toys.optflags & (FLAG_a|FLAG_p)) {
377     TT.pflags = CP_mode|CP_ownership|CP_timestamps;
378     umask(0);
379   }
380   // Not using comma_args() (yet?) because interpeting as letters.
381   if (CFG_CP_PRESERVE && (toys.optflags & FLAG_preserve)) {
382     char *pre = xstrdup(TT.c.preserve), *s;
383 
384     if (comma_scan(pre, "all", 1)) TT.pflags = ~0;
385     for (i=0; i<ARRAY_LEN(cp_preserve); i++)
386       if (comma_scan(pre, cp_preserve[i].name, 1)) TT.pflags |= 1<<i;
387     if (*pre) {
388 
389       // Try to interpret as letters, commas won't set anything this doesn't.
390       for (s = TT.c.preserve; *s; s++) {
391         for (i=0; i<ARRAY_LEN(cp_preserve); i++)
392           if (*s == *cp_preserve[i].name) break;
393         if (i == ARRAY_LEN(cp_preserve)) {
394           if (*s == 'a') TT.pflags = ~0;
395           else break;
396         } else TT.pflags |= 1<<i;
397       }
398 
399       if (*s) error_exit("bad --preserve=%s", pre);
400     }
401     free(pre);
402   }
403   if (!TT.callback) TT.callback = cp_node;
404 
405   // Loop through sources
406   for (i=0; i<toys.optc; i++) {
407     struct dirtree *new;
408     char *src = toys.optargs[i];
409     int rc = 1;
410 
411     if (destdir) TT.destname = xmprintf("%s/%s", destname, basename(src));
412     else TT.destname = destname;
413 
414     errno = EXDEV;
415     if (CFG_MV && toys.which->name[0] == 'm') {
416       if (!(toys.optflags & FLAG_f)) {
417         struct stat st;
418 
419         // Technically "is writeable" is more complicated (022 is not writeable
420         // by the owner, just everybody _else_) but I don't care.
421         if (!stat(TT.destname, &st)
422           && ((toys.optflags & FLAG_i) || !(st.st_mode & 0222)))
423         {
424           fprintf(stderr, "%s: overwrite '%s'", toys.which->name, TT.destname);
425           if (!yesno(1)) rc = 0;
426           else unlink(TT.destname);
427         }
428       }
429 
430       if (rc) rc = rename(src, TT.destname);
431     }
432 
433     // Skip nonexistent sources
434     if (rc) {
435       if (errno!=EXDEV ||
436         !(new = dirtree_start(src, toys.optflags&(FLAG_H|FLAG_L))))
437           perror_msg("bad '%s'", src);
438       else dirtree_handle_callback(new, TT.callback);
439     }
440     if (destdir) free(TT.destname);
441   }
442 }
443 
mv_main(void)444 void mv_main(void)
445 {
446   toys.optflags |= FLAG_d|FLAG_p|FLAG_R;
447 
448   cp_main();
449 }
450 
451 // Export cp flags into install's flag context.
452 
cp_flag_F(void)453 static inline int cp_flag_F(void) { return FLAG_F; };
cp_flag_p(void)454 static inline int cp_flag_p(void) { return FLAG_p; };
cp_flag_v(void)455 static inline int cp_flag_v(void) { return FLAG_v; };
456 
457 // Switch to install's flag context
458 #define CLEANUP_cp
459 #define FOR_install
460 #include <generated/flags.h>
461 
install_node(struct dirtree * try)462 static int install_node(struct dirtree *try)
463 {
464   try->st.st_mode = (TT.i.mode)
465     ? string_to_mode(TT.i.mode, try->st.st_mode) : 0755;
466   if (TT.i.group) try->st.st_gid = TT.gid;
467   if (TT.i.user) try->st.st_uid = TT.uid;
468 
469   // Always returns 0 because no -r
470   cp_node(try);
471 
472   // No -r so always one level deep, so destname as set by cp_node() is correct
473   if (toys.optflags & FLAG_s)
474     if (xrun((char *[]){"strip", "-p", TT.destname, 0})) toys.exitval = 1;
475 
476   return 0;
477 }
478 
install_main(void)479 void install_main(void)
480 {
481   char **ss;
482   int flags = toys.optflags;
483 
484   if (flags & FLAG_d) {
485     for (ss = toys.optargs; *ss; ss++) {
486       if (mkpathat(AT_FDCWD, *ss, 0777, 3)) perror_msg_raw(*ss);
487       if (flags & FLAG_v) printf("%s\n", *ss);
488     }
489 
490     return;
491   }
492 
493   if (toys.optflags & FLAG_D) {
494     TT.destname = toys.optargs[toys.optc-1];
495     if (mkpathat(AT_FDCWD, TT.destname, 0, 2))
496       perror_exit("-D '%s'", TT.destname);
497     if (toys.optc == 1) return;
498   }
499   if (toys.optc < 2) error_exit("needs 2 args");
500 
501   // Translate flags from install to cp
502   toys.optflags = cp_flag_F();
503   if (flags & FLAG_v) toys.optflags |= cp_flag_v();
504   if (flags & (FLAG_p|FLAG_o|FLAG_g)) toys.optflags |= cp_flag_p();
505 
506   if (TT.i.user) TT.uid = xgetpwnamid(TT.i.user)->pw_uid;
507   if (TT.i.group) TT.gid = xgetgrnamid(TT.i.group)->gr_gid;
508 
509   TT.callback = install_node;
510   cp_main();
511 }
512