X-Git-Url: https://git.dogcows.com/gitweb?a=blobdiff_plain;ds=sidebyside;f=src%2Fxattrs.c;h=a3f0b5f5b8740f5e43b822bfa6a5949ad571f711;hb=d36f5a3cc3280d6c4a58367bf51b527d5c14ac04;hp=e813d5388ad5c2048d8567eca198995a8e4fdbf8;hpb=696338043e52f440853e1143c52b81b41cd59723;p=chaz%2Ftar diff --git a/src/xattrs.c b/src/xattrs.c index e813d53..a3f0b5f 100644 --- a/src/xattrs.c +++ b/src/xattrs.c @@ -19,6 +19,7 @@ with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ +#include #include #include @@ -43,6 +44,318 @@ static struct struct xattrs_mask_map excl; } xattrs_setup; +/* disable posix acls when problem found in gnulib script m4/acl.m4 */ +#if ! USE_ACL +# undef HAVE_POSIX_ACLS +#endif + +#ifdef HAVE_POSIX_ACLS +# include "acl.h" +# include +#endif + +#ifdef HAVE_POSIX_ACLS + +/* acl-at wrappers, TODO: move to gnulib in future? */ +acl_t acl_get_file_at (int dirfd, const char *file, acl_type_t type); +int acl_set_file_at (int dirfd, const char *file, acl_type_t type, acl_t acl); +int file_has_acl_at (int dirfd, char const *, struct stat const *); + +/* acl_get_file_at */ +#define AT_FUNC_NAME acl_get_file_at +#define AT_FUNC_RESULT acl_t +#define AT_FUNC_FAIL (acl_t)NULL +#define AT_FUNC_F1 acl_get_file +#define AT_FUNC_POST_FILE_PARAM_DECLS , acl_type_t type +#define AT_FUNC_POST_FILE_ARGS , type +#include "at-func.c" +#undef AT_FUNC_NAME +#undef AT_FUNC_F1 +#undef AT_FUNC_RESULT +#undef AT_FUNC_FAIL +#undef AT_FUNC_POST_FILE_PARAM_DECLS +#undef AT_FUNC_POST_FILE_ARGS + +/* acl_set_file_at */ +#define AT_FUNC_NAME acl_set_file_at +#define AT_FUNC_F1 acl_set_file +#define AT_FUNC_POST_FILE_PARAM_DECLS , acl_type_t type, acl_t acl +#define AT_FUNC_POST_FILE_ARGS , type, acl +#include "at-func.c" +#undef AT_FUNC_NAME +#undef AT_FUNC_F1 +#undef AT_FUNC_POST_FILE_PARAM_DECLS +#undef AT_FUNC_POST_FILE_ARGS + +/* gnulib file_has_acl_at */ +#define AT_FUNC_NAME file_has_acl_at +#define AT_FUNC_F1 file_has_acl +#define AT_FUNC_POST_FILE_PARAM_DECLS , struct stat const *st +#define AT_FUNC_POST_FILE_ARGS , st +#include "at-func.c" +#undef AT_FUNC_NAME +#undef AT_FUNC_F1 +#undef AT_FUNC_POST_FILE_PARAM_DECLS +#undef AT_FUNC_POST_FILE_ARGS + +/* convert unix permissions into an ACL ... needed due to "default" ACLs */ +static acl_t perms2acl (int perms) +{ + char val[] = "user::---,group::---,other::---"; + /* 0123456789 123456789 123456789 123456789 */ + + /* user */ + if (perms & 0400) val[ 6] = 'r'; + if (perms & 0200) val[ 7] = 'w'; + if (perms & 0100) val[ 8] = 'x'; + + /* group */ + if (perms & 0040) val[17] = 'r'; + if (perms & 0020) val[18] = 'w'; + if (perms & 0010) val[19] = 'x'; + + /* other */ + if (perms & 0004) val[28] = 'r'; + if (perms & 0002) val[29] = 'w'; + if (perms & 0001) val[30] = 'x'; + + return (acl_from_text (val)); +} + +static char *skip_to_ext_fields (char *ptr) +{ + ptr += strcspn (ptr, ":,\n"); /* skip tag name. Ie. user/group/default/mask */ + + if (*ptr != ':') + return (ptr); /* error? no user/group field */ + ++ptr; + + ptr += strcspn (ptr, ":,\n"); /* skip user/group name */ + + if (*ptr != ':') + return (ptr); /* error? no perms field */ + ++ptr; + + ptr += strcspn (ptr, ":,\n"); /* skip perms */ + + if (*ptr != ':') + return (ptr); /* no extra fields */ + + return (ptr); +} + +/* The POSIX draft allows extra fields after the three main ones. Star + uses this to add a fourth field for user/group which is the numeric ID. + We just skip all extra fields atm. */ +static const char *fixup_extra_acl_fields (const char *ptr) +{ + char *src = (char *)ptr; + char *dst = (char *)ptr; + + while (*src) + { + const char *old = src; + size_t len = 0; + + src = skip_to_ext_fields (src); + len = src - old; + if (old != dst) memmove (dst, old, len); + dst += len; + + if (*src == ':') /* We have extra fields, skip them all */ + src += strcspn (src, "\n,"); + + if ((*src == '\n') || (*src == ',')) + *dst++ = *src++; /* also done when dst == src, but that's ok */ + } + if (src != dst) + *dst = 0; + + return ptr; +} + +static void xattrs__acls_set (struct tar_stat_info const *st, + char const *file_name, int type, + const char *ptr, size_t len, bool def) +{ /* "system.posix_acl_access" */ + acl_t acl; + + if (ptr) + { + /* assert (strlen (ptr) == len); */ + ptr = fixup_extra_acl_fields (ptr); + + acl = acl_from_text (ptr); + acls_option = 1; + } + else if (acls_option > 0) + acl = perms2acl (st->stat.st_mode); + else + return; /* don't call acl functions unless we first hit an ACL, or + --acls was passed explicitly */ + + if (acl == (acl_t)NULL) + { + call_arg_warn ("acl_from_text", file_name); + return; + } + + if (acl_set_file_at (chdir_fd, file_name, type, acl) == -1) + /* warn even if filesystem does not support acls */ + WARNOPT (WARN_XATTR_WRITE, (0, errno, + _("acl_set_file_at: Cannot set POSIX ACLs for file '%s'"), file_name)); + + acl_free (acl); +} + +static void xattrs__acls_get_a (int parentfd, const char *file_name, + struct tar_stat_info *st, + char **ret_ptr, size_t *ret_len) +{ /* "system.posix_acl_access" */ + char *val = NULL; + ssize_t len; + acl_t acl; + + if ((acl = acl_get_file_at (parentfd, file_name, ACL_TYPE_ACCESS)) + == (acl_t)NULL) + { + if (errno != ENOTSUP) + call_arg_warn ("acl_get_file_at", file_name); + return; + } + + val = acl_to_text (acl, &len); + acl_free (acl); + + if (val == NULL) + { + call_arg_warn ("acl_to_text", file_name); + return; + } + + *ret_ptr = xstrdup (val); + *ret_len = len; + + acl_free (val); +} + +static void xattrs__acls_get_d (int parentfd, char const *file_name, + struct tar_stat_info *st, + char **ret_ptr, size_t *ret_len) +{ /* "system.posix_acl_default" */ + char *val = NULL; + ssize_t len; + acl_t acl; + + if ((acl = acl_get_file_at (parentfd, file_name, ACL_TYPE_DEFAULT)) + == (acl_t)NULL) + { + if (errno != ENOTSUP) + call_arg_warn ("acl_get_file_at", file_name); + return; + } + + val = acl_to_text (acl, &len); + acl_free (acl); + + if (val == NULL) + { + call_arg_warn ("acl_to_text", file_name); + return; + } + + *ret_ptr = xstrdup (val); + *ret_len = len; + + acl_free (val); +} +#endif /* HAVE_POSIX_ACLS */ + +static void acls_one_line (const char *prefix, char delim, + const char *aclstring, size_t len) +{ + /* support both long and short text representation of posix acls */ + struct obstack stk; + obstack_init (&stk); + int pref_len = strlen (prefix); + const char *oldstring = aclstring; + + if (!aclstring || !len) + return; + + int pos = 0; + while (pos <= len) + { + int move = strcspn (aclstring, ",\n"); + if (!move) + break; + + if (oldstring != aclstring) + obstack_1grow (&stk, delim); + + obstack_grow (&stk, prefix, pref_len); + obstack_grow (&stk, aclstring, move); + + aclstring += move + 1; + } + + obstack_1grow (&stk, '\0'); + const char *toprint = obstack_finish (&stk); + + fprintf (stdlis, "%s", toprint); + + obstack_free (&stk, NULL); +} + +void xattrs_acls_get (int parentfd, char const *file_name, + struct tar_stat_info *st, int fd, int xisfile) +{ + if (acls_option > 0) + { +#ifndef HAVE_POSIX_ACLS + static int done = 0; + if (!done) + WARN ((0, 0, _("POSIX ACL support is not available"))); + done = 1; +#else + int err = file_has_acl_at (parentfd, file_name, &st->stat); + if (err == 0) + return; + if (err == -1) + { + call_arg_warn ("file_has_acl_at", file_name); + return; + } + + xattrs__acls_get_a (parentfd, file_name, st, + &st->acls_a_ptr, &st->acls_a_len); + if (!xisfile) + xattrs__acls_get_d (parentfd, file_name, st, + &st->acls_d_ptr, &st->acls_d_len); +#endif + } +} + +void xattrs_acls_set (struct tar_stat_info const *st, + char const *file_name, char typeflag) +{ + if ((acls_option > 0) && (typeflag != SYMTYPE)) + { +#ifndef HAVE_POSIX_ACLS + static int done = 0; + if (!done) + WARN ((0, 0, _("POSIX ACL support is not available"))); + done = 1; +#else + xattrs__acls_set (st, file_name, ACL_TYPE_ACCESS, + st->acls_a_ptr, st->acls_a_len, false); + if ((typeflag == DIRTYPE) || (typeflag == GNUTYPE_DUMPDIR)) + xattrs__acls_set (st, file_name, ACL_TYPE_DEFAULT, + st->acls_d_ptr, st->acls_d_len, true); +#endif + } +} + static void mask_map_realloc (struct xattrs_mask_map *map) { if (map->size == 0) @@ -276,7 +589,7 @@ void xattrs_print_char (struct tar_stat_info const *st, char *output) return; } - if (xattrs_option > 0) + if (xattrs_option > 0 || acls_option > 0) { /* placeholders */ *output = ' '; @@ -292,6 +605,9 @@ void xattrs_print_char (struct tar_stat_info const *st, char *output) *output = '*'; break; } + + if (acls_option && (st->acls_a_len || st->acls_d_len)) + *output = '+'; } void xattrs_print (struct tar_stat_info const *st) @@ -299,6 +615,15 @@ void xattrs_print (struct tar_stat_info const *st) if (verbose_option < 3) return; + /* acls */ + if (acls_option && (st->acls_a_len || st->acls_d_len)) + { + fprintf (stdlis, " a: "); + acls_one_line ("", ',', st->acls_a_ptr, st->acls_a_len); + acls_one_line ("default:", ',', st->acls_d_ptr, st->acls_d_len); + fprintf (stdlis, "\n"); + } + /* xattrs */ if (xattrs_option && st->xattr_map_size) {