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-rw-r--r--libmisc/copydir.c968
1 files changed, 968 insertions, 0 deletions
diff --git a/libmisc/copydir.c b/libmisc/copydir.c
new file mode 100644
index 0000000..b692aa9
--- /dev/null
+++ b/libmisc/copydir.c
@@ -0,0 +1,968 @@
+/*
+ * SPDX-FileCopyrightText: 1991 - 1994, Julianne Frances Haugh
+ * SPDX-FileCopyrightText: 1996 - 2001, Marek Michałkiewicz
+ * SPDX-FileCopyrightText: 2003 - 2006, Tomasz Kłoczko
+ * SPDX-FileCopyrightText: 2007 - 2010, Nicolas François
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <config.h>
+
+#ident "$Id$"
+
+#include <assert.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/time.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include "prototypes.h"
+#include "defines.h"
+#ifdef WITH_SELINUX
+#include <selinux/selinux.h>
+#endif /* WITH_SELINUX */
+#if defined(WITH_ACL) || defined(WITH_ATTR)
+#include <stdarg.h>
+#include <attr/error_context.h>
+#endif /* WITH_ACL || WITH_ATTR */
+#ifdef WITH_ACL
+#include <acl/libacl.h>
+#endif /* WITH_ACL */
+#ifdef WITH_ATTR
+#include <attr/libattr.h>
+#endif /* WITH_ATTR */
+#include "shadowlog.h"
+
+
+static /*@null@*/const char *src_orig;
+static /*@null@*/const char *dst_orig;
+
+struct link_name {
+ dev_t ln_dev;
+ ino_t ln_ino;
+ nlink_t ln_count;
+ char *ln_name;
+ /*@dependent@*/struct link_name *ln_next;
+};
+static /*@exposed@*/struct link_name *links;
+
+struct path_info {
+ const char *full_path;
+ int dirfd;
+ const char *name;
+};
+
+static int copy_entry (const struct path_info *src, const struct path_info *dst,
+ bool reset_selinux,
+ uid_t old_uid, uid_t new_uid,
+ gid_t old_gid, gid_t new_gid);
+static int copy_dir (const struct path_info *src, const struct path_info *dst,
+ bool reset_selinux,
+ const struct stat *statp, const struct timespec mt[],
+ uid_t old_uid, uid_t new_uid,
+ gid_t old_gid, gid_t new_gid);
+static /*@null@*/char *readlink_malloc (const char *filename);
+static int copy_symlink (const struct path_info *src, const struct path_info *dst,
+ unused bool reset_selinux,
+ const struct stat *statp, const struct timespec mt[],
+ uid_t old_uid, uid_t new_uid,
+ gid_t old_gid, gid_t new_gid);
+static int copy_hardlink (const struct path_info *dst,
+ unused bool reset_selinux,
+ struct link_name *lp);
+static int copy_special (const struct path_info *src, const struct path_info *dst,
+ bool reset_selinux,
+ const struct stat *statp, const struct timespec mt[],
+ uid_t old_uid, uid_t new_uid,
+ gid_t old_gid, gid_t new_gid);
+static int copy_file (const struct path_info *src, const struct path_info *dst,
+ bool reset_selinux,
+ const struct stat *statp, const struct timespec mt[],
+ uid_t old_uid, uid_t new_uid,
+ gid_t old_gid, gid_t new_gid);
+static int chownat_if_needed (const struct path_info *dst, const struct stat *statp,
+ uid_t old_uid, uid_t new_uid,
+ gid_t old_gid, gid_t new_gid);
+static int fchown_if_needed (int fdst, const struct stat *statp,
+ uid_t old_uid, uid_t new_uid,
+ gid_t old_gid, gid_t new_gid);
+
+#if defined(WITH_ACL) || defined(WITH_ATTR)
+/*
+ * error_acl - format the error messages for the ACL and EQ libraries.
+ */
+format_attr(printf, 2, 3)
+static void error_acl (unused struct error_context *ctx, const char *fmt, ...)
+{
+ va_list ap;
+ FILE *shadow_logfd = log_get_logfd();
+
+ /* ignore the case when destination does not support ACLs
+ * or extended attributes */
+ if (ENOTSUP == errno) {
+ errno = 0;
+ return;
+ }
+
+ va_start (ap, fmt);
+ (void) fprintf (shadow_logfd, _("%s: "), log_get_progname());
+ if (vfprintf (shadow_logfd, fmt, ap) != 0) {
+ (void) fputs (_(": "), shadow_logfd);
+ }
+ (void) fprintf (shadow_logfd, "%s\n", strerror (errno));
+ va_end (ap);
+}
+
+static struct error_context ctx = {
+ error_acl, NULL, NULL
+};
+#endif /* WITH_ACL || WITH_ATTR */
+
+#ifdef WITH_ACL
+static int perm_copy_path(const struct path_info *src,
+ const struct path_info *dst,
+ struct error_context *errctx)
+{
+ int src_fd, dst_fd, ret;
+
+ src_fd = openat(src->dirfd, src->name, O_RDONLY | O_NOFOLLOW | O_NONBLOCK | O_CLOEXEC);
+ if (src_fd < 0) {
+ return -1;
+ }
+
+ dst_fd = openat(dst->dirfd, dst->name, O_RDONLY | O_NOFOLLOW | O_NONBLOCK | O_CLOEXEC);
+ if (dst_fd < 0) {
+ (void) close (src_fd);
+ return -1;
+ }
+
+ ret = perm_copy_fd(src->full_path, src_fd, dst->full_path, dst_fd, errctx);
+ (void) close (src_fd);
+ (void) close (dst_fd);
+ return ret;
+}
+#endif /* WITH_ACL */
+
+#ifdef WITH_ATTR
+static int attr_copy_path(const struct path_info *src,
+ const struct path_info *dst,
+ int (*callback) (const char *, struct error_context *),
+ struct error_context *errctx)
+{
+ int src_fd, dst_fd, ret;
+
+ src_fd = openat(src->dirfd, src->name, O_RDONLY | O_NOFOLLOW | O_NONBLOCK | O_CLOEXEC);
+ if (src_fd < 0) {
+ return -1;
+ }
+
+ dst_fd = openat(dst->dirfd, dst->name, O_RDONLY | O_NOFOLLOW | O_NONBLOCK | O_CLOEXEC);
+ if (dst_fd < 0) {
+ (void) close (src_fd);
+ return -1;
+ }
+
+ ret = attr_copy_fd(src->full_path, src_fd, dst->full_path, dst_fd, callback, errctx);
+ (void) close (src_fd);
+ (void) close (dst_fd);
+ return ret;
+}
+#endif /* WITH_ATTR */
+
+/*
+ * remove_link - delete a link from the linked list
+ */
+static void remove_link (/*@only@*/struct link_name *ln)
+{
+ struct link_name *lp;
+
+ if (links == ln) {
+ links = ln->ln_next;
+ free (ln->ln_name);
+ free (ln);
+ return;
+ }
+ for (lp = links; NULL !=lp; lp = lp->ln_next) {
+ if (lp->ln_next == ln) {
+ break;
+ }
+ }
+
+ if (NULL == lp) {
+ free (ln->ln_name);
+ free (ln);
+ return;
+ }
+
+ lp->ln_next = lp->ln_next->ln_next;
+ free (ln->ln_name);
+ free (ln);
+}
+
+/*
+ * check_link - see if a file is really a link
+ */
+
+static /*@exposed@*/ /*@null@*/struct link_name *check_link (const char *name, const struct stat *sb)
+{
+ struct link_name *lp;
+ size_t src_len;
+ size_t dst_len;
+ size_t name_len;
+ size_t len;
+
+ /* copy_tree () must be the entry point */
+ assert (NULL != src_orig);
+ assert (NULL != dst_orig);
+
+ for (lp = links; NULL != lp; lp = lp->ln_next) {
+ if ((lp->ln_dev == sb->st_dev) && (lp->ln_ino == sb->st_ino)) {
+ return lp;
+ }
+ }
+
+ if (sb->st_nlink == 1) {
+ return NULL;
+ }
+
+ lp = (struct link_name *) xmalloc (sizeof *lp);
+ src_len = strlen (src_orig);
+ dst_len = strlen (dst_orig);
+ name_len = strlen (name);
+ lp->ln_dev = sb->st_dev;
+ lp->ln_ino = sb->st_ino;
+ lp->ln_count = sb->st_nlink;
+ len = name_len - src_len + dst_len + 1;
+ lp->ln_name = (char *) xmalloc (len);
+ (void) snprintf (lp->ln_name, len, "%s%s", dst_orig, name + src_len);
+ lp->ln_next = links;
+ links = lp;
+
+ return NULL;
+}
+
+static int copy_tree_impl (const struct path_info *src, const struct path_info *dst,
+ bool copy_root, bool reset_selinux,
+ uid_t old_uid, uid_t new_uid,
+ gid_t old_gid, gid_t new_gid)
+{
+ int dst_fd, src_fd, err = 0;
+ bool set_orig = false;
+ const struct dirent *ent;
+ DIR *dir;
+
+ if (copy_root) {
+ struct stat sb;
+
+ if ( fstatat (dst->dirfd, dst->name, &sb, 0) == 0
+ || errno != ENOENT) {
+ return -1;
+ }
+
+ if (fstatat (src->dirfd, src->name, &sb, AT_SYMLINK_NOFOLLOW) == -1) {
+ return -1;
+ }
+
+ if (!S_ISDIR (sb.st_mode)) {
+ fprintf (log_get_logfd(),
+ "%s: %s is not a directory",
+ log_get_progname(), src->full_path);
+ return -1;
+ }
+
+ return copy_entry (src, dst, reset_selinux,
+ old_uid, new_uid, old_gid, new_gid);
+ }
+
+ /*
+ * Make certain both directories exist. This routine is called
+ * after the home directory is created, or recursively after the
+ * target is created. It assumes the target directory exists.
+ */
+
+ src_fd = openat (src->dirfd, src->name, O_DIRECTORY | O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
+ if (src_fd < 0) {
+ return -1;
+ }
+
+ dst_fd = openat (dst->dirfd, dst->name, O_DIRECTORY | O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
+ if (dst_fd < 0) {
+ (void) close (src_fd);
+ return -1;
+ }
+
+ /*
+ * Open the source directory and read each entry. Every file
+ * entry in the directory is copied with the UID and GID set
+ * to the provided values. As an added security feature only
+ * regular files (and directories ...) are copied, and no file
+ * is made set-ID.
+ */
+ dir = fdopendir (src_fd);
+ if (NULL == dir) {
+ (void) close (src_fd);
+ (void) close (dst_fd);
+ return -1;
+ }
+
+ if (src_orig == NULL) {
+ src_orig = src->full_path;
+ dst_orig = dst->full_path;
+ set_orig = true;
+ }
+ while ((0 == err) && (ent = readdir (dir)) != NULL) {
+ /*
+ * Skip the "." and ".." entries
+ */
+ if ((strcmp (ent->d_name, ".") != 0) &&
+ (strcmp (ent->d_name, "..") != 0)) {
+ char *src_name;
+ char *dst_name;
+ size_t src_len = strlen (ent->d_name) + 2;
+ size_t dst_len = strlen (ent->d_name) + 2;
+ src_len += strlen (src->full_path);
+ dst_len += strlen (dst->full_path);
+
+ src_name = (char *) malloc (src_len);
+ dst_name = (char *) malloc (dst_len);
+
+ if ((NULL == src_name) || (NULL == dst_name)) {
+ err = -1;
+ } else {
+ /*
+ * Build the filename for both the source and
+ * the destination files.
+ */
+ struct path_info src_entry, dst_entry;
+
+ (void) snprintf (src_name, src_len, "%s/%s",
+ src->full_path, ent->d_name);
+ (void) snprintf (dst_name, dst_len, "%s/%s",
+ dst->full_path, ent->d_name);
+
+ src_entry.full_path = src_name;
+ src_entry.dirfd = dirfd(dir);
+ src_entry.name = ent->d_name;
+
+ dst_entry.full_path = dst_name;
+ dst_entry.dirfd = dst_fd;
+ dst_entry.name = ent->d_name;
+
+ err = copy_entry (&src_entry, &dst_entry,
+ reset_selinux,
+ old_uid, new_uid,
+ old_gid, new_gid);
+ }
+ free (src_name);
+ free (dst_name);
+ }
+ }
+ (void) closedir (dir);
+ (void) close (dst_fd);
+
+ if (set_orig) {
+ src_orig = NULL;
+ dst_orig = NULL;
+ /* FIXME: clean links
+ * Since there can be hardlinks elsewhere on the device,
+ * we cannot check that all the hardlinks were found:
+ assert (NULL == links);
+ */
+ }
+
+#ifdef WITH_SELINUX
+ /* Reset SELinux to create files with default contexts.
+ * Note that the context is only reset on exit of copy_tree (it is
+ * assumed that the program would quit without needing a restored
+ * context if copy_tree failed previously), and that copy_tree can
+ * be called recursively (hence the context is set on the
+ * sub-functions of copy_entry).
+ */
+ if (reset_selinux_file_context () != 0) {
+ err = -1;
+ }
+#endif /* WITH_SELINUX */
+
+ return err;
+}
+
+/*
+ * copy_entry - copy the entry of a directory
+ *
+ * Copy the entry src to dst.
+ * Depending on the type of entry, this function will forward the
+ * request to copy_dir(), copy_symlink(), copy_hardlink(),
+ * copy_special(), or copy_file().
+ *
+ * The access and modification time will not be modified.
+ *
+ * The permissions will be set to new_uid/new_gid.
+ *
+ * If new_uid (resp. new_gid) is equal to -1, the user (resp. group) will
+ * not be modified.
+ *
+ * Only the files owned (resp. group-owned) by old_uid (resp.
+ * old_gid) will be modified, unless old_uid (resp. old_gid) is set
+ * to -1.
+ */
+static int copy_entry (const struct path_info *src, const struct path_info *dst,
+ bool reset_selinux,
+ uid_t old_uid, uid_t new_uid,
+ gid_t old_gid, gid_t new_gid)
+{
+ int err = 0;
+ struct stat sb;
+ struct link_name *lp;
+ struct timespec mt[2];
+
+ if (fstatat(src->dirfd, src->name, &sb, AT_SYMLINK_NOFOLLOW) == -1) {
+ /* If we cannot stat the file, do not care. */
+ } else {
+#ifdef HAVE_STRUCT_STAT_ST_ATIM
+ mt[0].tv_sec = sb.st_atim.tv_sec;
+ mt[0].tv_nsec = sb.st_atim.tv_nsec;
+#else /* !HAVE_STRUCT_STAT_ST_ATIM */
+ mt[0].tv_sec = sb.st_atime;
+# ifdef HAVE_STRUCT_STAT_ST_ATIMENSEC
+ mt[0].tv_nsec = sb.st_atimensec;
+# else /* !HAVE_STRUCT_STAT_ST_ATIMENSEC */
+ mt[0].tv_nsec = 0;
+# endif /* !HAVE_STRUCT_STAT_ST_ATIMENSEC */
+#endif /* !HAVE_STRUCT_STAT_ST_ATIM */
+
+#ifdef HAVE_STRUCT_STAT_ST_MTIM
+ mt[1].tv_sec = sb.st_mtim.tv_sec;
+ mt[1].tv_nsec = sb.st_mtim.tv_nsec;
+#else /* !HAVE_STRUCT_STAT_ST_MTIM */
+ mt[1].tv_sec = sb.st_mtime;
+# ifdef HAVE_STRUCT_STAT_ST_MTIMENSEC
+ mt[1].tv_nsec = sb.st_mtimensec;
+# else /* !HAVE_STRUCT_STAT_ST_MTIMENSEC */
+ mt[1].tv_nsec = 0;
+# endif /* !HAVE_STRUCT_STAT_ST_MTIMENSEC */
+#endif /* !HAVE_STRUCT_STAT_ST_MTIM */
+
+ if (S_ISDIR (sb.st_mode)) {
+ err = copy_dir (src, dst, reset_selinux, &sb, mt,
+ old_uid, new_uid, old_gid, new_gid);
+ }
+
+ /*
+ * Copy any symbolic links
+ */
+
+ else if (S_ISLNK (sb.st_mode)) {
+ err = copy_symlink (src, dst, reset_selinux, &sb, mt,
+ old_uid, new_uid, old_gid, new_gid);
+ }
+
+ /*
+ * See if this is a previously copied link
+ */
+
+ else if ((lp = check_link (src->full_path, &sb)) != NULL) {
+ err = copy_hardlink (dst, reset_selinux, lp);
+ }
+
+ /*
+ * Deal with FIFOs and special files. The user really
+ * shouldn't have any of these, but it seems like it
+ * would be nice to copy everything ...
+ */
+
+ else if (!S_ISREG (sb.st_mode)) {
+ err = copy_special (src, dst, reset_selinux, &sb, mt,
+ old_uid, new_uid, old_gid, new_gid);
+ }
+
+ /*
+ * Create the new file and copy the contents. The new
+ * file will be owned by the provided UID and GID values.
+ */
+
+ else {
+ err = copy_file (src, dst, reset_selinux, &sb, mt,
+ old_uid, new_uid, old_gid, new_gid);
+ }
+ }
+
+ return err;
+}
+
+/*
+ * copy_dir - copy a directory
+ *
+ * Copy a directory (recursively) from src to dst.
+ *
+ * statp, mt, old_uid, new_uid, old_gid, and new_gid are used to set
+ * the access and modification and the access rights.
+ *
+ * Return 0 on success, -1 on error.
+ */
+static int copy_dir (const struct path_info *src, const struct path_info *dst,
+ bool reset_selinux,
+ const struct stat *statp, const struct timespec mt[],
+ uid_t old_uid, uid_t new_uid,
+ gid_t old_gid, gid_t new_gid)
+{
+ int err = 0;
+
+ /*
+ * Create a new target directory, make it owned by
+ * the user and then recursively copy that directory.
+ */
+
+#ifdef WITH_SELINUX
+ if (set_selinux_file_context (dst->full_path, S_IFDIR) != 0) {
+ return -1;
+ }
+#endif /* WITH_SELINUX */
+ if ( (mkdirat (dst->dirfd, dst->name, 0700) != 0)
+ || (chownat_if_needed (dst, statp,
+ old_uid, new_uid, old_gid, new_gid) != 0)
+ || (fchmodat (dst->dirfd, dst->name, statp->st_mode & 07777, AT_SYMLINK_NOFOLLOW) != 0)
+#ifdef WITH_ACL
+ || ( (perm_copy_path (src, dst, &ctx) != 0)
+ && (errno != 0))
+#endif /* WITH_ACL */
+#ifdef WITH_ATTR
+ /*
+ * If the third parameter is NULL, all extended attributes
+ * except those that define Access Control Lists are copied.
+ * ACLs are excluded by default because copying them between
+ * file systems with and without ACL support needs some
+ * additional logic so that no unexpected permissions result.
+ */
+ || ( !reset_selinux
+ && (attr_copy_path (src, dst, NULL, &ctx) != 0)
+ && (errno != 0))
+#endif /* WITH_ATTR */
+ || (copy_tree_impl (src, dst, false, reset_selinux,
+ old_uid, new_uid, old_gid, new_gid) != 0)
+ || (utimensat (dst->dirfd, dst->name, mt, AT_SYMLINK_NOFOLLOW) != 0)) {
+ err = -1;
+ }
+
+ return err;
+}
+
+/*
+ * readlink_malloc - wrapper for readlink
+ *
+ * return NULL on error.
+ * The return string shall be freed by the caller.
+ */
+static /*@null@*/char *readlink_malloc (const char *filename)
+{
+ size_t size = 1024;
+
+ while (true) {
+ ssize_t nchars;
+ char *buffer = (char *) malloc (size);
+ if (NULL == buffer) {
+ return NULL;
+ }
+
+ nchars = readlink (filename, buffer, size);
+
+ if (nchars < 0) {
+ free(buffer);
+ return NULL;
+ }
+
+ if ((size_t) nchars < size) { /* The buffer was large enough */
+ /* readlink does not nul-terminate */
+ buffer[nchars] = '\0';
+ return buffer;
+ }
+
+ /* Try again with a bigger buffer */
+ free (buffer);
+ size *= 2;
+ }
+}
+
+/*
+ * copy_symlink - copy a symlink
+ *
+ * Copy a symlink from src to dst.
+ *
+ * statp, mt, old_uid, new_uid, old_gid, and new_gid are used to set
+ * the access and modification and the access rights.
+ *
+ * Return 0 on success, -1 on error.
+ */
+static int copy_symlink (const struct path_info *src, const struct path_info *dst,
+ unused bool reset_selinux,
+ const struct stat *statp, const struct timespec mt[],
+ uid_t old_uid, uid_t new_uid,
+ gid_t old_gid, gid_t new_gid)
+{
+ char *oldlink;
+
+ /* copy_tree () must be the entry point */
+ assert (NULL != src_orig);
+ assert (NULL != dst_orig);
+
+ /*
+ * Get the name of the file which the link points
+ * to. If that name begins with the original
+ * source directory name, that part of the link
+ * name will be replaced with the original
+ * destination directory name.
+ */
+
+ oldlink = readlink_malloc (src->full_path);
+ if (NULL == oldlink) {
+ return -1;
+ }
+
+ /* If src was a link to an entry of the src_orig directory itself,
+ * create a link to the corresponding entry in the dst_orig
+ * directory.
+ */
+ if (strncmp (oldlink, src_orig, strlen (src_orig)) == 0) {
+ size_t len = strlen (dst_orig) + strlen (oldlink) - strlen (src_orig) + 1;
+ char *dummy = (char *) xmalloc (len);
+ (void) snprintf (dummy, len, "%s%s",
+ dst_orig,
+ oldlink + strlen (src_orig));
+ free (oldlink);
+ oldlink = dummy;
+ }
+
+#ifdef WITH_SELINUX
+ if (set_selinux_file_context (dst->full_path, S_IFLNK) != 0) {
+ free (oldlink);
+ return -1;
+ }
+#endif /* WITH_SELINUX */
+ if ( (symlinkat (oldlink, dst->dirfd, dst->name) != 0)
+ || (chownat_if_needed (dst, statp,
+ old_uid, new_uid, old_gid, new_gid) != 0)) {
+ /* FIXME: there are no modes on symlinks, right?
+ * ACL could be copied, but this would be much more
+ * complex than calling perm_copy_file.
+ * Ditto for Extended Attributes.
+ * We currently only document that ACL and Extended
+ * Attributes are not copied.
+ */
+ free (oldlink);
+ return -1;
+ }
+ free (oldlink);
+
+ if (utimensat (dst->dirfd, dst->name, mt, AT_SYMLINK_NOFOLLOW) != 0) {
+ return -1;
+ }
+
+ return 0;
+}
+
+/*
+ * copy_hardlink - copy a hardlink
+ *
+ * Copy a hardlink from src to dst.
+ *
+ * Return 0 on success, -1 on error.
+ */
+static int copy_hardlink (const struct path_info *dst,
+ unused bool reset_selinux,
+ struct link_name *lp)
+{
+ /* FIXME: selinux, ACL, Extended Attributes needed? */
+
+ if (linkat (AT_FDCWD, lp->ln_name, dst->dirfd, dst->name, 0) != 0) {
+ return -1;
+ }
+
+ /* If the file could be unlinked, decrement the links counter,
+ * and forget about this link if it was the last reference */
+ lp->ln_count--;
+ if (lp->ln_count <= 0) {
+ remove_link (lp);
+ }
+
+ return 0;
+}
+
+/*
+ * copy_special - copy a special file
+ *
+ * Copy a special file from src to dst.
+ *
+ * statp, mt, old_uid, new_uid, old_gid, and new_gid are used to set
+ * the access and modification and the access rights.
+ *
+ * Return 0 on success, -1 on error.
+ */
+static int copy_special (const struct path_info *src, const struct path_info *dst,
+ bool reset_selinux,
+ const struct stat *statp, const struct timespec mt[],
+ uid_t old_uid, uid_t new_uid,
+ gid_t old_gid, gid_t new_gid)
+{
+ int err = 0;
+
+#ifdef WITH_SELINUX
+ if (set_selinux_file_context (dst->full_path, statp->st_mode & S_IFMT) != 0) {
+ return -1;
+ }
+#endif /* WITH_SELINUX */
+
+ if ( (mknodat (dst->dirfd, dst->name, statp->st_mode & ~07777U, statp->st_rdev) != 0)
+ || (chownat_if_needed (dst, statp,
+ old_uid, new_uid, old_gid, new_gid) != 0)
+ || (fchmodat (dst->dirfd, dst->name, statp->st_mode & 07777, AT_SYMLINK_NOFOLLOW) != 0)
+#ifdef WITH_ACL
+ || ( (perm_copy_path (src, dst, &ctx) != 0)
+ && (errno != 0))
+#endif /* WITH_ACL */
+#ifdef WITH_ATTR
+ /*
+ * If the third parameter is NULL, all extended attributes
+ * except those that define Access Control Lists are copied.
+ * ACLs are excluded by default because copying them between
+ * file systems with and without ACL support needs some
+ * additional logic so that no unexpected permissions result.
+ */
+ || ( !reset_selinux
+ && (attr_copy_path (src, dst, NULL, &ctx) != 0)
+ && (errno != 0))
+#endif /* WITH_ATTR */
+ || (utimensat (dst->dirfd, dst->name, mt, AT_SYMLINK_NOFOLLOW) != 0)) {
+ err = -1;
+ }
+
+ return err;
+}
+
+/*
+ * full_write - write entire buffer
+ *
+ * Write up to count bytes from the buffer starting at buf to the
+ * file referred to by the file descriptor fd.
+ * Retry in case of a short write.
+ *
+ * Returns the number of bytes written on success, -1 on error.
+ */
+static ssize_t full_write(int fd, const void *buf, size_t count) {
+ ssize_t written = 0;
+
+ while (count > 0) {
+ ssize_t res;
+
+ res = write(fd, buf, count);
+ if (res < 0) {
+ if (errno == EINTR) {
+ continue;
+ }
+
+ return res;
+ }
+
+ if (res == 0) {
+ break;
+ }
+
+ written += res;
+ buf = (const unsigned char*)buf + res;
+ count -= (size_t)res;
+ }
+
+ return written;
+}
+
+/*
+ * copy_file - copy a file
+ *
+ * Copy a file from src to dst.
+ *
+ * statp, mt, old_uid, new_uid, old_gid, and new_gid are used to set
+ * the access and modification and the access rights.
+ *
+ * Return 0 on success, -1 on error.
+ */
+static int copy_file (const struct path_info *src, const struct path_info *dst,
+ bool reset_selinux,
+ const struct stat *statp, const struct timespec mt[],
+ uid_t old_uid, uid_t new_uid,
+ gid_t old_gid, gid_t new_gid)
+{
+ int err = 0;
+ int ifd;
+ int ofd;
+
+ ifd = openat (src->dirfd, src->name, O_RDONLY|O_NOFOLLOW|O_CLOEXEC);
+ if (ifd < 0) {
+ return -1;
+ }
+#ifdef WITH_SELINUX
+ if (set_selinux_file_context (dst->full_path, S_IFREG) != 0) {
+ (void) close (ifd);
+ return -1;
+ }
+#endif /* WITH_SELINUX */
+ ofd = openat (dst->dirfd, dst->name, O_WRONLY | O_CREAT | O_EXCL | O_TRUNC | O_NOFOLLOW | O_CLOEXEC, 0600);
+ if ( (ofd < 0)
+ || (fchown_if_needed (ofd, statp,
+ old_uid, new_uid, old_gid, new_gid) != 0)
+ || (fchmod (ofd, statp->st_mode & 07777) != 0)
+#ifdef WITH_ACL
+ || ( (perm_copy_fd (src->full_path, ifd, dst->full_path, ofd, &ctx) != 0)
+ && (errno != 0))
+#endif /* WITH_ACL */
+#ifdef WITH_ATTR
+ /*
+ * If the third parameter is NULL, all extended attributes
+ * except those that define Access Control Lists are copied.
+ * ACLs are excluded by default because copying them between
+ * file systems with and without ACL support needs some
+ * additional logic so that no unexpected permissions result.
+ */
+ || ( !reset_selinux
+ && (attr_copy_fd (src->full_path, ifd, dst->full_path, ofd, NULL, &ctx) != 0)
+ && (errno != 0))
+#endif /* WITH_ATTR */
+ ) {
+ if (ofd >= 0) {
+ (void) close (ofd);
+ }
+ (void) close (ifd);
+ return -1;
+ }
+
+ while (true) {
+ char buf[8192];
+ ssize_t cnt;
+
+ cnt = read (ifd, buf, sizeof buf);
+ if (cnt < 0) {
+ if (errno == EINTR) {
+ continue;
+ }
+ (void) close (ofd);
+ (void) close (ifd);
+ return -1;
+ }
+ if (cnt == 0) {
+ break;
+ }
+
+ if (full_write (ofd, buf, (size_t)cnt) < 0) {
+ (void) close (ofd);
+ (void) close (ifd);
+ return -1;
+ }
+ }
+
+ (void) close (ifd);
+ if (close (ofd) != 0) {
+ return -1;
+ }
+
+ if (utimensat (dst->dirfd, dst->name, mt, AT_SYMLINK_NOFOLLOW) != 0) {
+ return -1;
+ }
+
+ return err;
+}
+
+#define def_chown_if_needed(chown_function, type_dst) \
+static int chown_function ## _if_needed (type_dst dst, \
+ const struct stat *statp, \
+ uid_t old_uid, uid_t new_uid, \
+ gid_t old_gid, gid_t new_gid) \
+{ \
+ uid_t tmpuid = (uid_t) -1; \
+ gid_t tmpgid = (gid_t) -1; \
+ \
+ /* Use new_uid if old_uid is set to -1 or if the file was \
+ * owned by the user. */ \
+ if (((uid_t) -1 == old_uid) || (statp->st_uid == old_uid)) { \
+ tmpuid = new_uid; \
+ } \
+ /* Otherwise, or if new_uid was set to -1, we keep the same \
+ * owner. */ \
+ if ((uid_t) -1 == tmpuid) { \
+ tmpuid = statp->st_uid; \
+ } \
+ \
+ if (((gid_t) -1 == old_gid) || (statp->st_gid == old_gid)) { \
+ tmpgid = new_gid; \
+ } \
+ if ((gid_t) -1 == tmpgid) { \
+ tmpgid = statp->st_gid; \
+ } \
+ \
+ return chown_function (dst, tmpuid, tmpgid); \
+}
+
+def_chown_if_needed (fchown, int)
+
+static int chownat_if_needed (const struct path_info *dst,
+ const struct stat *statp,
+ uid_t old_uid, uid_t new_uid,
+ gid_t old_gid, gid_t new_gid)
+{
+ uid_t tmpuid = (uid_t) -1;
+ gid_t tmpgid = (gid_t) -1;
+
+ /* Use new_uid if old_uid is set to -1 or if the file was
+ * owned by the user. */
+ if (((uid_t) -1 == old_uid) || (statp->st_uid == old_uid)) {
+ tmpuid = new_uid;
+ }
+ /* Otherwise, or if new_uid was set to -1, we keep the same
+ * owner. */
+ if ((uid_t) -1 == tmpuid) {
+ tmpuid = statp->st_uid;
+ }
+
+ if (((gid_t) -1 == old_gid) || (statp->st_gid == old_gid)) {
+ tmpgid = new_gid;
+ }
+ if ((gid_t) -1 == tmpgid) {
+ tmpgid = statp->st_gid;
+ }
+
+ return fchownat (dst->dirfd, dst->name, tmpuid, tmpgid, AT_SYMLINK_NOFOLLOW);
+}
+
+/*
+ * copy_tree - copy files in a directory tree
+ *
+ * copy_tree() walks a directory tree and copies ordinary files
+ * as it goes.
+ *
+ * When reset_selinux is enabled, extended attributes (and thus
+ * SELinux attributes) are not copied.
+ *
+ * old_uid and new_uid are used to set the ownership of the copied
+ * files. Unless old_uid is set to -1, only the files owned by
+ * old_uid have their ownership changed to new_uid. In addition, if
+ * new_uid is set to -1, no ownership will be changed.
+ *
+ * The same logic applies for the group-ownership and
+ * old_gid/new_gid.
+ */
+int copy_tree (const char *src_root, const char *dst_root,
+ bool copy_root, bool reset_selinux,
+ uid_t old_uid, uid_t new_uid,
+ gid_t old_gid, gid_t new_gid)
+{
+ const struct path_info src = {
+ .full_path = src_root,
+ .dirfd = AT_FDCWD,
+ .name = src_root
+ };
+ const struct path_info dst = {
+ .full_path = dst_root,
+ .dirfd = AT_FDCWD,
+ .name = dst_root
+ };
+
+ return copy_tree_impl(&src, &dst, copy_root, reset_selinux,
+ old_uid, new_uid, old_gid, new_gid);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-05 20:30:03 +0000