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  * Deviations from posix: -adlnrsvF, --preserve... about half the
10  * functionality in this cp isn't in posix. Posix is stuck in the 1970's.
11  *
12  * TODO: --preserve=links
13  * TODO: what's this _CP_mode system.posix_acl_ business? We chmod()?
14 
15 // options shared between mv/cp must be in same order (right to left)
16 // for FLAG macros to work out right in shared infrastructure.
17 
18 USE_CP(NEWTOY(cp, "<1(preserve):;D(parents)RHLPprudaslvnF(remove-destination)fit:T[-HLPd][-niu]", TOYFLAG_BIN))
19 USE_MV(NEWTOY(mv, "<1vnF(remove-destination)fit:T[-ni]", TOYFLAG_BIN))
20 USE_INSTALL(NEWTOY(install, "<1cdDpsvt:m:o:g:", TOYFLAG_USR|TOYFLAG_BIN))
21 
22 config CP
23   bool "cp"
24   default y
25   help
26     usage: cp [-adfHiLlnPpRrsTv] [--preserve=motcxa] [-t TARGET] SOURCE... [DEST]
27 
28     Copy files from SOURCE to DEST.  If more than one SOURCE, DEST must
29     be a directory.
30 
31     -a	Same as -dpr
32     -D	Create leading dirs under DEST (--parents)
33     -d	Don't dereference symlinks
34     -F	Delete any existing destination file first (--remove-destination)
35     -f	Delete destination files we can't write to
36     -H	Follow symlinks listed on command line
37     -i	Interactive, prompt before overwriting existing DEST
38     -L	Follow all symlinks
39     -l	Hard link instead of copy
40     -n	No clobber (don't overwrite DEST)
41     -u	Update (keep newest mtime)
42     -P	Do not follow symlinks
43     -p	Preserve timestamps, ownership, and mode
44     -R	Recurse into subdirectories (DEST must be a directory)
45     -r	Synonym for -R
46     -s	Symlink instead of copy
47     -t	Copy to TARGET dir (no DEST)
48     -T	DEST always treated as file, max 2 arguments
49     -v	Verbose
50 
51     Arguments to --preserve are the first letter(s) of:
52 
53             mode - permissions (ignore umask for rwx, copy suid and sticky bit)
54        ownership - user and group
55       timestamps - file creation, modification, and access times.
56          context - security context
57            xattr - extended attributes
58              all - all of the above
59 
60 config MV
61   bool "mv"
62   default y
63   help
64     usage: mv [-finTv] [-t TARGET] SOURCE... [DEST]
65 
66     -f	Force copy by deleting destination file
67     -i	Interactive, prompt before overwriting existing DEST
68     -n	No clobber (don't overwrite DEST)
69     -t	Move to TARGET dir (no DEST)
70     -T	DEST always treated as file, max 2 arguments
71     -v	Verbose
72 
73 config INSTALL
74   bool "install"
75   default y
76   help
77     usage: install [-dDpsv] [-o USER] [-g GROUP] [-m MODE] [-t TARGET] [SOURCE...] [DEST]
78 
79     Copy files and set attributes.
80 
81     -d	Act like mkdir -p
82     -D	Create leading directories for DEST
83     -g	Make copy belong to GROUP
84     -m	Set permissions to MODE
85     -o	Make copy belong to USER
86     -p	Preserve timestamps
87     -s	Call "strip -p"
88     -t	Copy files to TARGET dir (no DEST)
89     -v	Verbose
90 */
91 
92 #define FORCE_FLAGS
93 #define FOR_cp
94 #include "toys.h"
95 
96 GLOBALS(
97   union {
98     // install's options
99     struct {
100       char *g, *o, *m, *t;
101     } i;
102     // cp's options
103     struct {
104       char *t, *preserve;
105     } c;
106   };
107 
108   char *destname;
109   struct stat top;
110   int (*callback)(struct dirtree *try);
111   uid_t uid;
112   gid_t gid;
113   int pflags;
114 )
115 
116 struct cp_preserve {
117   char *name;
118 } static const cp_preserve[] = TAGGED_ARRAY(CP,
119   {"mode"}, {"ownership"}, {"timestamps"}, {"context"}, {"xattr"},
120 );
121 
122 // Callback from dirtree_read() for each file/directory under a source dir.
123 
cp_node(struct dirtree * try)124 static int cp_node(struct dirtree *try)
125 {
126   int fdout = -1, cfd = try->parent ? try->parent->extra : AT_FDCWD,
127       tfd = dirtree_parentfd(try);
128   unsigned flags = toys.optflags;
129   char *catch = try->parent ? try->name : TT.destname, *err = "%s";
130   struct stat cst;
131 
132   if (!dirtree_notdotdot(try)) return 0;
133 
134   // If returning from COMEAGAIN, jump straight to -p logic at end.
135   if (S_ISDIR(try->st.st_mode) && try->again) {
136     fdout = try->extra;
137     err = 0;
138   } else {
139 
140     // -d is only the same as -r for symlinks, not for directories
141     if (S_ISLNK(try->st.st_mode) && (flags & FLAG_d)) flags |= FLAG_r;
142 
143     // Detect recursive copies via repeated top node (cp -R .. .) or
144     // identical source/target (fun with hardlinks).
145     if ((TT.top.st_dev == try->st.st_dev && TT.top.st_ino == try->st.st_ino
146          && (catch = TT.destname))
147         || (!fstatat(cfd, catch, &cst, 0) && cst.st_dev == try->st.st_dev
148          && cst.st_ino == try->st.st_ino))
149     {
150       error_msg("'%s' is '%s'", catch, err = dirtree_path(try, 0));
151       free(err);
152 
153       return 0;
154     }
155 
156     // Handle -inuvF
157 
158     if (!faccessat(cfd, catch, F_OK, 0) && !S_ISDIR(cst.st_mode)) {
159       char *s;
160 
161       if (S_ISDIR(try->st.st_mode)) {
162         error_msg("dir at '%s'", s = dirtree_path(try, 0));
163         free(s);
164         return 0;
165       } else if ((flags & FLAG_F) && unlinkat(cfd, catch, 0)) {
166         error_msg("unlink '%s'", catch);
167         return 0;
168       } else if (flags & FLAG_n) return 0;
169       else if ((flags & FLAG_u) && nanodiff(&try->st.st_mtim, &cst.st_mtim)>0)
170         return 0;
171       else if (flags & FLAG_i) {
172         fprintf(stderr, "%s: overwrite '%s'", toys.which->name,
173           s = dirtree_path(try, 0));
174         free(s);
175         if (!yesno(0)) return 0;
176       }
177     }
178 
179     if (flags & FLAG_v) {
180       char *s = dirtree_path(try, 0);
181       printf("%s '%s'\n", toys.which->name, s);
182       free(s);
183     }
184 
185     // Loop for -f retry after unlink
186     do {
187 
188       // directory, hardlink, symlink, mknod (char, block, fifo, socket), file
189 
190       // Copy directory
191 
192       if (S_ISDIR(try->st.st_mode)) {
193         struct stat st2;
194 
195         if (!(flags & (FLAG_a|FLAG_r|FLAG_R))) {
196           err = "Skipped dir '%s'";
197           catch = try->name;
198           break;
199         }
200 
201         // Always make directory writeable to us, so we can create files in it.
202         //
203         // Yes, there's a race window between mkdir() and open() so it's
204         // possible that -p can be made to chown a directory other than the one
205         // we created. The closest we can do to closing this is make sure
206         // that what we open _is_ a directory rather than something else.
207 
208         if (!mkdirat(cfd, catch, try->st.st_mode | 0200) || errno == EEXIST)
209           if (-1 != (try->extra = openat(cfd, catch, O_NOFOLLOW)))
210             if (!fstat(try->extra, &st2) && S_ISDIR(st2.st_mode))
211               return DIRTREE_COMEAGAIN | (DIRTREE_SYMFOLLOW*!!FLAG(L));
212 
213       // Hardlink
214 
215       } else if (flags & FLAG_l) {
216         if (!linkat(tfd, try->name, cfd, catch, 0)) err = 0;
217 
218       // Copy tree as symlinks. For non-absolute paths this involves
219       // appending the right number of .. entries as you go down the tree.
220 
221       } else if (flags & FLAG_s) {
222         char *s;
223         struct dirtree *or;
224         int dotdots = 0;
225 
226         s = dirtree_path(try, 0);
227         for (or = try; or->parent; or = or->parent) dotdots++;
228 
229         if (*or->name == '/') dotdots = 0;
230         if (dotdots) {
231           char *s2 = xmprintf("%*c%s", 3*dotdots, ' ', s);
232           free(s);
233           s = s2;
234           while(dotdots--) {
235             memcpy(s2, "../", 3);
236             s2 += 3;
237           }
238         }
239         if (!symlinkat(s, cfd, catch)) {
240           err = 0;
241           fdout = AT_FDCWD;
242         }
243         free(s);
244 
245       // Do something _other_ than copy contents of a file?
246       } else if (!S_ISREG(try->st.st_mode)
247                  && (try->parent || (flags & (FLAG_a|FLAG_P|FLAG_r))))
248       {
249         int i;
250 
251         // make symlink, or make block/char/fifo/socket
252         if (S_ISLNK(try->st.st_mode)
253             ? ((i = readlinkat0(tfd, try->name, toybuf, sizeof(toybuf))) &&
254                ((!unlinkat(cfd, catch, 0) || ENOENT == errno) &&
255                 !symlinkat(toybuf, cfd, catch)))
256             : !mknodat(cfd, catch, try->st.st_mode, try->st.st_rdev))
257         {
258           err = 0;
259           fdout = AT_FDCWD;
260         }
261 
262       // Copy contents of file.
263       } else {
264         int fdin;
265 
266         fdin = openat(tfd, try->name, O_RDONLY);
267         if (fdin < 0) {
268           catch = try->name;
269           break;
270         }
271         // When copying contents use symlink target's attributes
272         if (S_ISLNK(try->st.st_mode)) fstat(fdin, &try->st);
273         fdout = openat(cfd, catch, O_RDWR|O_CREAT|O_TRUNC, try->st.st_mode);
274         if (fdout >= 0) {
275           xsendfile(fdin, fdout);
276           err = 0;
277         }
278 
279         // We only copy xattrs for files because there's no flistxattrat()
280         if (TT.pflags&(_CP_xattr|_CP_context)) {
281           ssize_t listlen = xattr_flist(fdin, 0, 0), len;
282           char *name, *value, *list;
283 
284           if (listlen>0) {
285             list = xmalloc(listlen);
286             xattr_flist(fdin, list, listlen);
287             list[listlen-1] = 0; // I do not trust this API.
288             for (name = list; name-list < listlen; name += strlen(name)+1) {
289               if (!(TT.pflags&_CP_xattr) && strncmp(name, "security.", 9))
290                 continue;
291               if ((len = xattr_fget(fdin, name, 0, 0))>0) {
292                 value = xmalloc(len);
293                 if (len == xattr_fget(fdin, name, value, len))
294                   if (xattr_fset(fdout, name, value, len, 0))
295                     perror_msg("%s setxattr(%s=%s)", catch, name, value);
296                 free(value);
297               }
298             }
299             free(list);
300           }
301         }
302 
303         close(fdin);
304       }
305     } while (err && (flags & (FLAG_f|FLAG_n)) && !unlinkat(cfd, catch, 0));
306   }
307 
308   // Did we make a thing?
309   if (fdout != -1) {
310     int rc;
311 
312     // Inability to set --preserve isn't fatal, some require root access.
313 
314     // ownership
315     if (TT.pflags & _CP_ownership) {
316 
317       // permission bits already correct for mknod and don't apply to symlink
318       // If we can't get a filehandle to the actual object, use racy functions
319       if (fdout == AT_FDCWD)
320         rc = fchownat(cfd, catch, try->st.st_uid, try->st.st_gid,
321                       AT_SYMLINK_NOFOLLOW);
322       else rc = fchown(fdout, try->st.st_uid, try->st.st_gid);
323       if (rc && !geteuid()) {
324         char *pp;
325 
326         perror_msg("chown '%s'", pp = dirtree_path(try, 0));
327         free(pp);
328       }
329     }
330 
331     // timestamp
332     if (TT.pflags & _CP_timestamps) {
333       struct timespec times[] = {try->st.st_atim, try->st.st_mtim};
334 
335       if (fdout == AT_FDCWD) utimensat(cfd, catch, times, AT_SYMLINK_NOFOLLOW);
336       else futimens(fdout, times);
337     }
338 
339     // mode comes last because other syscalls can strip suid bit
340     if (fdout != AT_FDCWD) {
341       if (TT.pflags & _CP_mode) fchmod(fdout, try->st.st_mode);
342       xclose(fdout);
343     }
344 
345     if (CFG_MV && toys.which->name[0] == 'm')
346       if (unlinkat(tfd, try->name, S_ISDIR(try->st.st_mode) ? AT_REMOVEDIR :0))
347         err = "%s";
348   }
349 
350   if (err) {
351     char *f = 0;
352 
353     if (catch == try->name) {
354       f = dirtree_path(try, 0);
355       while (try->parent) try = try->parent;
356       catch = xmprintf("%s%s", TT.destname, f+strlen(try->name));
357       free(f);
358       f = catch;
359     }
360     perror_msg(err, catch);
361     free(f);
362   }
363   return 0;
364 }
365 
cp_main(void)366 void cp_main(void)
367 {
368   char *tt = *toys.which->name == 'i' ? TT.i.t : TT.c.t,
369     *destname = tt ? : toys.optargs[--toys.optc];
370   int i, destdir = !stat(destname, &TT.top);
371 
372   if (!toys.optc) error_exit("Needs 2 arguments");
373   if (!destdir && errno==ENOENT && FLAG(D)) {
374     if (tt && mkpathat(AT_FDCWD, tt, 0777, MKPATHAT_MAKE|MKPATHAT_MKLAST))
375       perror_exit("-t '%s'", tt);
376     destdir = 1;
377   } else {
378     destdir = destdir && S_ISDIR(TT.top.st_mode);
379     if (!destdir && (toys.optc>1 || FLAG(D) || tt))
380       error_exit("'%s' not directory", destname);
381   }
382 
383   if (FLAG(T)) {
384     if (toys.optc>1) help_exit("Max 2 arguments");
385     if (destdir) error_exit("'%s' is a directory", destname);
386   }
387 
388   if (FLAG(a)||FLAG(p)) TT.pflags = _CP_mode|_CP_ownership|_CP_timestamps;
389 
390   // Not using comma_args() (yet?) because interpeting as letters.
391   if (FLAG(preserve)) {
392     char *pre = xstrdup(TT.c.preserve ? TT.c.preserve : "mot"), *s;
393 
394     if (comma_remove(pre, "all")) TT.pflags = ~0;
395     for (i=0; i<ARRAY_LEN(cp_preserve); i++)
396       while (comma_remove(pre, cp_preserve[i].name)) TT.pflags |= 1<<i;
397     if (*pre) {
398 
399       // Try to interpret as letters, commas won't set anything this doesn't.
400       for (s = pre; *s; s++) {
401         for (i=0; i<ARRAY_LEN(cp_preserve); i++)
402           if (*s == *cp_preserve[i].name) break;
403         if (i == ARRAY_LEN(cp_preserve)) {
404           if (*s == 'a') TT.pflags = ~0;
405           else break;
406         } else TT.pflags |= 1<<i;
407       }
408 
409       if (*s) error_exit("bad --preserve=%s", pre);
410     }
411     free(pre);
412   }
413   if (TT.pflags & _CP_mode) umask(0);
414   if (!TT.callback) TT.callback = cp_node;
415 
416   // Loop through sources
417   for (i=0; i<toys.optc; i++) {
418     char *src = toys.optargs[i], *trail;
419     int send = 1;
420 
421     if (!(trail = strrchr(src, '/')) || trail[1]) trail = 0;
422     else while (trail>src && *trail=='/') *trail-- = 0;
423 
424     if (destdir) {
425       char *s = FLAG(D) ? src : getbasename(src);
426 
427       TT.destname = xmprintf("%s/%s", destname, s);
428       if (FLAG(D)) {
429         if (!(s = fileunderdir(TT.destname, destname))) {
430           error_msg("%s not under %s", TT.destname, destname);
431           continue;
432         }
433         // TODO: .. follows abspath, not links...
434         free(s);
435         mkpath(TT.destname);
436       }
437     } else TT.destname = destname;
438 
439     // "mv across devices" triggers cp fallback path, so set that as default
440     errno = EXDEV;
441     if (CFG_MV && toys.which->name[0] == 'm') {
442       int force = FLAG(f), no_clobber = FLAG(n);
443 
444       if (!force || no_clobber) {
445         struct stat st;
446         int exists = !stat(TT.destname, &st);
447 
448         // Prompt if -i or file isn't writable.  Technically "is writable" is
449         // more complicated (022 is not writeable by the owner, just everybody
450         // _else_) but I don't care.
451         if (exists && (FLAG(i) || (!(st.st_mode & 0222) && isatty(0)))) {
452           fprintf(stderr, "%s: overwrite '%s'", toys.which->name, TT.destname);
453           if (!yesno(0)) send = 0;
454           else unlink(TT.destname);
455         }
456         // if -n and dest exists, don't try to rename() or copy
457         if (exists && no_clobber) send = 0;
458       }
459       if (send) send = rename(src, TT.destname);
460       if (trail) trail[1] = '/';
461     }
462 
463     // Copy if we didn't mv or hit an error, skipping nonexistent sources
464     if (send) {
465       if (errno!=EXDEV || dirtree_flagread(src, DIRTREE_SHUTUP+
466         DIRTREE_SYMFOLLOW*!!(FLAG(H)||FLAG(L)), TT.callback))
467           perror_msg("bad '%s'", src);
468     }
469     if (destdir) free(TT.destname);
470   }
471 }
472 
mv_main(void)473 void mv_main(void)
474 {
475   toys.optflags |= FLAG_d|FLAG_p|FLAG_R;
476 
477   cp_main();
478 }
479 
480 // Export cp flags into install's flag context.
481 
cp_flag_F(void)482 static inline int cp_flag_F(void) { return FLAG_F; };
cp_flag_p(void)483 static inline int cp_flag_p(void) { return FLAG_p; };
cp_flag_v(void)484 static inline int cp_flag_v(void) { return FLAG_v; };
485 
486 // Switch to install's flag context
487 #define CLEANUP_cp
488 #define FOR_install
489 #include <generated/flags.h>
490 
install_node(struct dirtree * try)491 static int install_node(struct dirtree *try)
492 {
493   try->st.st_mode = TT.i.m ? string_to_mode(TT.i.m, try->st.st_mode) : 0755;
494   if (TT.i.g) try->st.st_gid = TT.gid;
495   if (TT.i.o) try->st.st_uid = TT.uid;
496 
497   // Always returns 0 because no -r
498   cp_node(try);
499 
500   // No -r so always one level deep, so destname as set by cp_node() is correct
501   if (FLAG(s) && xrun((char *[]){"strip", "-p", TT.destname, 0}))
502     toys.exitval = 1;
503 
504   return 0;
505 }
506 
install_main(void)507 void install_main(void)
508 {
509   char **ss;
510 
511   TT.uid = TT.i.o ? xgetuid(TT.i.o) : -1;
512   TT.gid = TT.i.g ? xgetgid(TT.i.g) : -1;
513 
514   if (FLAG(d)) {
515     for (ss = toys.optargs; *ss; ss++) {
516       if (FLAG(v)) printf("%s\n", *ss);
517       if (mkpathat(AT_FDCWD, *ss, 0777, MKPATHAT_MKLAST | MKPATHAT_MAKE))
518         perror_msg_raw(*ss);
519       if (FLAG(g)||FLAG(o))
520         if (lchown(*ss, TT.uid, TT.gid)) perror_msg("chown '%s'", *ss);
521     }
522 
523     return;
524   }
525 
526   if (FLAG(D)) {
527     char *destname = FLAG(t) ? TT.i.t : (TT.destname = toys.optargs[toys.optc-1]);
528     if (mkpathat(AT_FDCWD, destname, 0777, MKPATHAT_MAKE | (FLAG(t) ? MKPATHAT_MKLAST : 0)))
529       perror_exit("-D '%s'", destname);
530     if (toys.optc == !FLAG(t)) return;
531   }
532 
533   // Translate flags from install to cp
534   toys.optflags = cp_flag_F() + cp_flag_v()*!!FLAG(v)
535     + cp_flag_p()*!!(FLAG(p)|FLAG(o)|FLAG(g));
536 
537   TT.callback = install_node;
538   cp_main();
539 }
540