From 3970acf7ddb9aa01c4bdeef197495157c98a15f6 Mon Sep 17 00:00:00 2001 From: Boris Protopopov Date: Fri, 18 Dec 2020 11:30:12 -0600 Subject: SMB3: Add support for getting and setting SACLs Add SYSTEM_SECURITY access flag and use with smb2 when opening files for getting/setting SACLs. Add "system.cifs_ntsd_full" extended attribute to allow user-space access to the functionality. Avoid multiple server calls when setting owner, DACL, and SACL. Signed-off-by: Boris Protopopov Signed-off-by: Steve French --- fs/cifs/xattr.c | 83 ++++++++++++++++++++++++++++++++++++++++++--------------- 1 file changed, 62 insertions(+), 21 deletions(-) (limited to 'fs/cifs/xattr.c') diff --git a/fs/cifs/xattr.c b/fs/cifs/xattr.c index b8299173ea7e..9318a2acf4ee 100644 --- a/fs/cifs/xattr.c +++ b/fs/cifs/xattr.c @@ -34,6 +34,7 @@ #define MAX_EA_VALUE_SIZE CIFSMaxBufSize #define CIFS_XATTR_CIFS_ACL "system.cifs_acl" /* DACL only */ #define CIFS_XATTR_CIFS_NTSD "system.cifs_ntsd" /* owner plus DACL */ +#define CIFS_XATTR_CIFS_NTSD_FULL "system.cifs_ntsd_full" /* owner/DACL/SACL */ #define CIFS_XATTR_ATTRIB "cifs.dosattrib" /* full name: user.cifs.dosattrib */ #define CIFS_XATTR_CREATETIME "cifs.creationtime" /* user.cifs.creationtime */ /* @@ -43,12 +44,13 @@ */ #define SMB3_XATTR_CIFS_ACL "system.smb3_acl" /* DACL only */ #define SMB3_XATTR_CIFS_NTSD "system.smb3_ntsd" /* owner plus DACL */ +#define SMB3_XATTR_CIFS_NTSD_FULL "system.smb3_ntsd_full" /* owner/DACL/SACL */ #define SMB3_XATTR_ATTRIB "smb3.dosattrib" /* full name: user.smb3.dosattrib */ #define SMB3_XATTR_CREATETIME "smb3.creationtime" /* user.smb3.creationtime */ /* BB need to add server (Samba e.g) support for security and trusted prefix */ enum { XATTR_USER, XATTR_CIFS_ACL, XATTR_ACL_ACCESS, XATTR_ACL_DEFAULT, - XATTR_CIFS_NTSD }; + XATTR_CIFS_NTSD, XATTR_CIFS_NTSD_FULL }; static int cifs_attrib_set(unsigned int xid, struct cifs_tcon *pTcon, struct inode *inode, char *full_path, @@ -164,7 +166,8 @@ static int cifs_xattr_set(const struct xattr_handler *handler, break; case XATTR_CIFS_ACL: - case XATTR_CIFS_NTSD: { + case XATTR_CIFS_NTSD: + case XATTR_CIFS_NTSD_FULL: { struct cifs_ntsd *pacl; if (!value) @@ -174,23 +177,27 @@ static int cifs_xattr_set(const struct xattr_handler *handler, rc = -ENOMEM; } else { memcpy(pacl, value, size); - if (value && - pTcon->ses->server->ops->set_acl) { + if (pTcon->ses->server->ops->set_acl) { + int aclflags = 0; rc = 0; - if (handler->flags == XATTR_CIFS_NTSD) { - /* set owner and DACL */ - rc = pTcon->ses->server->ops->set_acl( - pacl, size, inode, - full_path, - CIFS_ACL_OWNER); - } - if (rc == 0) { - /* set DACL */ - rc = pTcon->ses->server->ops->set_acl( - pacl, size, inode, - full_path, - CIFS_ACL_DACL); + + switch (handler->flags) { + case XATTR_CIFS_NTSD_FULL: + aclflags = (CIFS_ACL_OWNER | + CIFS_ACL_DACL | + CIFS_ACL_SACL); + break; + case XATTR_CIFS_NTSD: + aclflags = (CIFS_ACL_OWNER | + CIFS_ACL_DACL); + break; + case XATTR_CIFS_ACL: + default: + aclflags = CIFS_ACL_DACL; } + + rc = pTcon->ses->server->ops->set_acl(pacl, + size, inode, full_path, aclflags); } else { rc = -EOPNOTSUPP; } @@ -327,16 +334,27 @@ static int cifs_xattr_get(const struct xattr_handler *handler, break; case XATTR_CIFS_ACL: - case XATTR_CIFS_NTSD: { - /* the whole ntsd is fetched regardless */ - u32 acllen; + case XATTR_CIFS_NTSD: + case XATTR_CIFS_NTSD_FULL: { + /* + * fetch owner, DACL, and SACL if asked for full descriptor, + * fetch owner and DACL otherwise + */ + u32 acllen, additional_info = 0; struct cifs_ntsd *pacl; if (pTcon->ses->server->ops->get_acl == NULL) goto out; /* rc already EOPNOTSUPP */ + if (handler->flags == XATTR_CIFS_NTSD_FULL) { + additional_info = OWNER_SECINFO | GROUP_SECINFO | + DACL_SECINFO | SACL_SECINFO; + } else { + additional_info = OWNER_SECINFO | GROUP_SECINFO | + DACL_SECINFO; + } pacl = pTcon->ses->server->ops->get_acl(cifs_sb, - inode, full_path, &acllen); + inode, full_path, &acllen, additional_info); if (IS_ERR(pacl)) { rc = PTR_ERR(pacl); cifs_dbg(VFS, "%s: error %zd getting sec desc\n", @@ -486,6 +504,27 @@ static const struct xattr_handler smb3_ntsd_xattr_handler = { .set = cifs_xattr_set, }; +static const struct xattr_handler cifs_cifs_ntsd_full_xattr_handler = { + .name = CIFS_XATTR_CIFS_NTSD_FULL, + .flags = XATTR_CIFS_NTSD_FULL, + .get = cifs_xattr_get, + .set = cifs_xattr_set, +}; + +/* + * Although this is just an alias for the above, need to move away from + * confusing users and using the 20 year old term 'cifs' when it is no + * longer secure and was replaced by SMB2/SMB3 a long time ago, and + * SMB3 and later are highly secure. + */ +static const struct xattr_handler smb3_ntsd_full_xattr_handler = { + .name = SMB3_XATTR_CIFS_NTSD_FULL, + .flags = XATTR_CIFS_NTSD_FULL, + .get = cifs_xattr_get, + .set = cifs_xattr_set, +}; + + static const struct xattr_handler cifs_posix_acl_access_xattr_handler = { .name = XATTR_NAME_POSIX_ACL_ACCESS, .flags = XATTR_ACL_ACCESS, @@ -507,6 +546,8 @@ const struct xattr_handler *cifs_xattr_handlers[] = { &smb3_acl_xattr_handler, /* alias for above since avoiding "cifs" */ &cifs_cifs_ntsd_xattr_handler, &smb3_ntsd_xattr_handler, /* alias for above since avoiding "cifs" */ + &cifs_cifs_ntsd_full_xattr_handler, + &smb3_ntsd_full_xattr_handler, /* alias for above since avoiding "cifs" */ &cifs_posix_acl_access_xattr_handler, &cifs_posix_acl_default_xattr_handler, NULL -- cgit v1.2.3-59-g8ed1b