1 files changed, 301 insertions, 0 deletions
diff --git a/lib/sysxattrs.c b/lib/sysxattrs.c
new file mode 100644
index 0000000..ca08d13
--- /dev/null
+++ b/lib/sysxattrs.c
@@ -0,0 +1,301 @@
+/*
+ * Extended attribute support for rsync.
+ *
+ * Copyright (C) 2004 Red Hat, Inc.
+ * Copyright (C) 2003-2022 Wayne Davison
+ * Written by Jay Fenlason.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, visit the http://fsf.org website.
+ */
+
+#include "rsync.h"
+#include "sysxattrs.h"
+
+#ifdef SUPPORT_XATTRS
+
+#ifdef HAVE_OSX_XATTRS
+#define GETXATTR_FETCH_LIMIT (64*1024*1024)
+#endif
+
+#if defined HAVE_LINUX_XATTRS
+
+ssize_t sys_lgetxattr(const char *path, const char *name, void *value, size_t size)
+{
+	return lgetxattr(path, name, value, size);
+}
+
+ssize_t sys_fgetxattr(int filedes, const char *name, void *value, size_t size)
+{
+	return fgetxattr(filedes, name, value, size);
+}
+
+int sys_lsetxattr(const char *path, const char *name, const void *value, size_t size)
+{
+	return lsetxattr(path, name, value, size, 0);
+}
+
+int sys_lremovexattr(const char *path, const char *name)
+{
+	return lremovexattr(path, name);
+}
+
+ssize_t sys_llistxattr(const char *path, char *list, size_t size)
+{
+	return llistxattr(path, list, size);
+}
+
+#elif HAVE_OSX_XATTRS
+
+ssize_t sys_lgetxattr(const char *path, const char *name, void *value, size_t size)
+{
+	ssize_t len = getxattr(path, name, value, size, 0, XATTR_NOFOLLOW);
+
+	/* If we're retrieving data, handle resource forks > 64MB specially */
+	if (value != NULL && len == GETXATTR_FETCH_LIMIT && (size_t)len < size) {
+		/* getxattr will only return 64MB of data at a time, need to call again with a new offset */
+		u_int32_t offset = len;
+		size_t data_retrieved = len;
+		while (data_retrieved < size) {
+			len = getxattr(path, name, (char*)value + offset, size - data_retrieved, offset, XATTR_NOFOLLOW);
+			if (len <= 0)
+				break;
+			data_retrieved += len;
+			offset += (u_int32_t)len;
+		}
+		len = data_retrieved;
+	}
+
+	return len;
+}
+
+ssize_t sys_fgetxattr(int filedes, const char *name, void *value, size_t size)
+{
+	return fgetxattr(filedes, name, value, size, 0, 0);
+}
+
+int sys_lsetxattr(const char *path, const char *name, const void *value, size_t size)
+{
+	return setxattr(path, name, value, size, 0, XATTR_NOFOLLOW);
+}
+
+int sys_lremovexattr(const char *path, const char *name)
+{
+	return removexattr(path, name, XATTR_NOFOLLOW);
+}
+
+ssize_t sys_llistxattr(const char *path, char *list, size_t size)
+{
+	return listxattr(path, list, size, XATTR_NOFOLLOW);
+}
+
+#elif HAVE_FREEBSD_XATTRS
+
+ssize_t sys_lgetxattr(const char *path, const char *name, void *value, size_t size)
+{
+	return extattr_get_link(path, EXTATTR_NAMESPACE_USER, name, value, size);
+}
+
+ssize_t sys_fgetxattr(int filedes, const char *name, void *value, size_t size)
+{
+	return extattr_get_fd(filedes, EXTATTR_NAMESPACE_USER, name, value, size);
+}
+
+int sys_lsetxattr(const char *path, const char *name, const void *value, size_t size)
+{
+	return extattr_set_link(path, EXTATTR_NAMESPACE_USER, name, value, size);
+}
+
+int sys_lremovexattr(const char *path, const char *name)
+{
+	return extattr_delete_link(path, EXTATTR_NAMESPACE_USER, name);
+}
+
+ssize_t sys_llistxattr(const char *path, char *list, size_t size)
+{
+	unsigned char keylen;
+	ssize_t off, len = extattr_list_link(path, EXTATTR_NAMESPACE_USER, list, size);
+
+	if (len <= 0 || (size_t)len > size)
+		return len;
+
+	/* FreeBSD puts a single-byte length before each string, with no '\0'
+	 * terminator.  We need to change this into a series of null-terminted
+	 * strings.  Since the size is the same, we can simply transform the
+	 * output in place. */
+	for (off = 0; off < len; off += keylen + 1) {
+		keylen = ((unsigned char*)list)[off];
+		if (off + keylen >= len) {
+			/* Should be impossible, but kernel bugs happen! */
+			errno = EINVAL;
+			return -1;
+		}
+		memmove(list+off, list+off+1, keylen);
+		list[off+keylen] = '\0';
+	}
+
+	return len;
+}
+
+#elif HAVE_SOLARIS_XATTRS
+
+static ssize_t read_xattr(int attrfd, void *buf, size_t buflen)
+{
+	STRUCT_STAT sb;
+	ssize_t ret;
+
+	if (fstat(attrfd, &sb) < 0)
+		ret = -1;
+	else if (sb.st_size > SSIZE_MAX) {
+		errno = ERANGE;
+		ret = -1;
+	} else if (buflen == 0)
+		ret = sb.st_size;
+	else if (sb.st_size > buflen) {
+		errno = ERANGE;
+		ret = -1;
+	} else {
+		size_t bufpos;
+		for (bufpos = 0; bufpos < sb.st_size; ) {
+			ssize_t cnt = read(attrfd, (char*)buf + bufpos, sb.st_size - bufpos);
+			if (cnt <= 0) {
+				if (cnt < 0 && errno == EINTR)
+					continue;
+				bufpos = -1;
+				break;
+			}
+			bufpos += cnt;
+		}
+		ret = bufpos;
+	}
+
+	close(attrfd);
+
+	return ret;
+}
+
+ssize_t sys_lgetxattr(const char *path, const char *name, void *value, size_t size)
+{
+	int attrfd;
+
+	if ((attrfd = attropen(path, name, O_RDONLY)) < 0) {
+		errno = ENOATTR;
+		return -1;
+	}
+
+	return read_xattr(attrfd, value, size);
+}
+
+ssize_t sys_fgetxattr(int filedes, const char *name, void *value, size_t size)
+{
+	int attrfd;
+
+	if ((attrfd = openat(filedes, name, O_RDONLY|O_XATTR, 0)) < 0) {
+		errno = ENOATTR;
+		return -1;
+	}
+
+	return read_xattr(attrfd, value, size);
+}
+
+int sys_lsetxattr(const char *path, const char *name, const void *value, size_t size)
+{
+	int attrfd;
+	size_t bufpos;
+	mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP;
+
+	if ((attrfd = attropen(path, name, O_CREAT|O_TRUNC|O_WRONLY, mode)) < 0)
+		return -1;
+
+	for (bufpos = 0; bufpos < size; ) {
+		ssize_t cnt = write(attrfd, (char*)value + bufpos, size);
+		if (cnt <= 0) {
+			if (cnt < 0 && errno == EINTR)
+				continue;
+			bufpos = -1;
+			break;
+		}
+		bufpos += cnt;
+	}
+
+	close(attrfd);
+
+	return bufpos > 0 ? 0 : -1;
+}
+
+int sys_lremovexattr(const char *path, const char *name)
+{
+	int attrdirfd;
+	int ret;
+
+	if ((attrdirfd = attropen(path, ".", O_RDONLY)) < 0)
+		return -1;
+
+	ret = unlinkat(attrdirfd, name, 0);
+
+	close(attrdirfd);
+
+	return ret;
+}
+
+ssize_t sys_llistxattr(const char *path, char *list, size_t size)
+{
+	int attrdirfd;
+	DIR *dirp;
+	struct dirent *dp;
+	ssize_t ret = 0;
+
+	if ((attrdirfd = attropen(path, ".", O_RDONLY)) < 0) {
+		errno = ENOTSUP;
+		return -1;
+	}
+
+	if ((dirp = fdopendir(attrdirfd)) == NULL) {
+		close(attrdirfd);
+		return -1;
+	}
+
+	while ((dp = readdir(dirp))) {
+		int len = strlen(dp->d_name);
+
+		if (dp->d_name[0] == '.' && (len == 1 || (len == 2 && dp->d_name[1] == '.')))
+			continue;
+		if (len == 11 && dp->d_name[0] == 'S' && strncmp(dp->d_name, "SUNWattr_r", 10) == 0
+		 && (dp->d_name[10] == 'o' || dp->d_name[10] == 'w'))
+			continue;
+
+		ret += len + 1;
+		if ((size_t)ret > size) {
+			if (size == 0)
+				continue;
+			ret = -1;
+			errno = ERANGE;
+			break;
+		}
+		memcpy(list, dp->d_name, len+1);
+		list += len+1;
+	}
+
+	closedir(dirp);
+	close(attrdirfd);
+
+	return ret;
+}
+
+#else
+
+#error You need to create xattr compatibility functions.
+
+#endif
+
+#endif /* SUPPORT_XATTRS */