2022-05-14 14:58:42

by Trond Myklebust

[permalink] [raw]
Subject: [PATCH 0/3] Export the NFSv4.1 'dacl' and 'sacl' attributes

From: Trond Myklebust <[email protected]>

This patch series allows the NFSv4 client to also export the NFSv4.1
'dacl' and 'sacl' attributes.
The main differences with respect to the existing NFSv4 'acl' attribute
are:

1) by splitting out the 'sacl' component, the server is free to enforce
stronger privilege requirements against users that want to read or
modify the sacl auditing features, while still allowing ordinary
users to read and modify the 'dacl'.
2) Support for automatic inheritance of acls.

These two differences do mean that the acl tools will need some
modifications in order to make use of the new functionality.

Trond Myklebust (3):
NFSv4: Specify the type of ACL to cache
NFSv4: Add encoders/decoders for the NFSv4.1 dacl and sacl attributes
NFSv4.1: Enable access to the NFSv4.1 'dacl' and 'sacl' attributes

fs/nfs/nfs4proc.c | 137 +++++++++++++++++++++++++++++++++-------
fs/nfs/nfs4xdr.c | 95 ++++++++++++++++++----------
include/linux/nfs4.h | 2 +
include/linux/nfs_xdr.h | 10 +++
4 files changed, 189 insertions(+), 55 deletions(-)

--
2.36.1



2022-05-14 21:16:49

by Trond Myklebust

[permalink] [raw]
Subject: [PATCH 1/3] NFSv4: Specify the type of ACL to cache

From: Trond Myklebust <[email protected]>

When caching a NFSv4 ACL, we want to specify whether we are caching an
NFSv4.0 type acl, the NFSv4.1 dacl or the NFSv4.1 sacl.

Signed-off-by: Trond Myklebust <[email protected]>
---
fs/nfs/nfs4proc.c | 59 ++++++++++++++++++++++++++++-------------
include/linux/nfs4.h | 2 ++
include/linux/nfs_xdr.h | 7 +++++
3 files changed, 49 insertions(+), 19 deletions(-)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index bf3ba541b9fb..e6c830d4db0b 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -5772,9 +5772,17 @@ static int nfs4_proc_renew(struct nfs_client *clp, const struct cred *cred)
return 0;
}

-static inline int nfs4_server_supports_acls(struct nfs_server *server)
+static bool nfs4_server_supports_acls(const struct nfs_server *server,
+ enum nfs4_acl_type type)
{
- return server->caps & NFS_CAP_ACLS;
+ switch (type) {
+ default:
+ return server->attr_bitmask[0] & FATTR4_WORD0_ACL;
+ case NFS4ACL_DACL:
+ return server->attr_bitmask[1] & FATTR4_WORD1_DACL;
+ case NFS4ACL_SACL:
+ return server->attr_bitmask[1] & FATTR4_WORD1_SACL;
+ }
}

/* Assuming that XATTR_SIZE_MAX is a multiple of PAGE_SIZE, and that
@@ -5813,6 +5821,7 @@ int nfs4_buf_to_pages_noslab(const void *buf, size_t buflen,
}

struct nfs4_cached_acl {
+ enum nfs4_acl_type type;
int cached;
size_t len;
char data[];
@@ -5833,7 +5842,8 @@ static void nfs4_zap_acl_attr(struct inode *inode)
nfs4_set_cached_acl(inode, NULL);
}

-static inline ssize_t nfs4_read_cached_acl(struct inode *inode, char *buf, size_t buflen)
+static ssize_t nfs4_read_cached_acl(struct inode *inode, char *buf,
+ size_t buflen, enum nfs4_acl_type type)
{
struct nfs_inode *nfsi = NFS_I(inode);
struct nfs4_cached_acl *acl;
@@ -5843,6 +5853,8 @@ static inline ssize_t nfs4_read_cached_acl(struct inode *inode, char *buf, size_
acl = nfsi->nfs4_acl;
if (acl == NULL)
goto out;
+ if (acl->type != type)
+ goto out;
if (buf == NULL) /* user is just asking for length */
goto out_len;
if (acl->cached == 0)
@@ -5858,7 +5870,9 @@ static inline ssize_t nfs4_read_cached_acl(struct inode *inode, char *buf, size_
return ret;
}

-static void nfs4_write_cached_acl(struct inode *inode, struct page **pages, size_t pgbase, size_t acl_len)
+static void nfs4_write_cached_acl(struct inode *inode, struct page **pages,
+ size_t pgbase, size_t acl_len,
+ enum nfs4_acl_type type)
{
struct nfs4_cached_acl *acl;
size_t buflen = sizeof(*acl) + acl_len;
@@ -5875,6 +5889,7 @@ static void nfs4_write_cached_acl(struct inode *inode, struct page **pages, size
goto out;
acl->cached = 0;
}
+ acl->type = type;
acl->len = acl_len;
out:
nfs4_set_cached_acl(inode, acl);
@@ -5890,7 +5905,8 @@ static void nfs4_write_cached_acl(struct inode *inode, struct page **pages, size
* length. The next getxattr call will then produce another round trip to
* the server, this time with the input buf of the required size.
*/
-static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t buflen)
+static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf,
+ size_t buflen, enum nfs4_acl_type type)
{
struct page **pages;
struct nfs_getaclargs args = {
@@ -5947,7 +5963,8 @@ static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t bu
ret = -ERANGE;
goto out_free;
}
- nfs4_write_cached_acl(inode, pages, res.acl_data_offset, res.acl_len);
+ nfs4_write_cached_acl(inode, pages, res.acl_data_offset, res.acl_len,
+ type);
if (buf) {
if (res.acl_len > buflen) {
ret = -ERANGE;
@@ -5967,14 +5984,15 @@ static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t bu
return ret;
}

-static ssize_t nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t buflen)
+static ssize_t nfs4_get_acl_uncached(struct inode *inode, void *buf,
+ size_t buflen, enum nfs4_acl_type type)
{
struct nfs4_exception exception = {
.interruptible = true,
};
ssize_t ret;
do {
- ret = __nfs4_get_acl_uncached(inode, buf, buflen);
+ ret = __nfs4_get_acl_uncached(inode, buf, buflen, type);
trace_nfs4_get_acl(inode, ret);
if (ret >= 0)
break;
@@ -5983,27 +6001,29 @@ static ssize_t nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t bufl
return ret;
}

-static ssize_t nfs4_proc_get_acl(struct inode *inode, void *buf, size_t buflen)
+static ssize_t nfs4_proc_get_acl(struct inode *inode, void *buf, size_t buflen,
+ enum nfs4_acl_type type)
{
struct nfs_server *server = NFS_SERVER(inode);
int ret;

- if (!nfs4_server_supports_acls(server))
+ if (!nfs4_server_supports_acls(server, type))
return -EOPNOTSUPP;
ret = nfs_revalidate_inode(inode, NFS_INO_INVALID_CHANGE);
if (ret < 0)
return ret;
if (NFS_I(inode)->cache_validity & NFS_INO_INVALID_ACL)
nfs_zap_acl_cache(inode);
- ret = nfs4_read_cached_acl(inode, buf, buflen);
+ ret = nfs4_read_cached_acl(inode, buf, buflen, type);
if (ret != -ENOENT)
/* -ENOENT is returned if there is no ACL or if there is an ACL
* but no cached acl data, just the acl length */
return ret;
- return nfs4_get_acl_uncached(inode, buf, buflen);
+ return nfs4_get_acl_uncached(inode, buf, buflen, type);
}

-static int __nfs4_proc_set_acl(struct inode *inode, const void *buf, size_t buflen)
+static int __nfs4_proc_set_acl(struct inode *inode, const void *buf,
+ size_t buflen, enum nfs4_acl_type type)
{
struct nfs_server *server = NFS_SERVER(inode);
struct page *pages[NFS4ACL_MAXPAGES];
@@ -6024,7 +6044,7 @@ static int __nfs4_proc_set_acl(struct inode *inode, const void *buf, size_t bufl
/* You can't remove system.nfs4_acl: */
if (buflen == 0)
return -EINVAL;
- if (!nfs4_server_supports_acls(server))
+ if (!nfs4_server_supports_acls(server, type))
return -EOPNOTSUPP;
if (npages > ARRAY_SIZE(pages))
return -ERANGE;
@@ -6055,12 +6075,13 @@ static int __nfs4_proc_set_acl(struct inode *inode, const void *buf, size_t bufl
return ret;
}

-static int nfs4_proc_set_acl(struct inode *inode, const void *buf, size_t buflen)
+static int nfs4_proc_set_acl(struct inode *inode, const void *buf,
+ size_t buflen, enum nfs4_acl_type type)
{
struct nfs4_exception exception = { };
int err;
do {
- err = __nfs4_proc_set_acl(inode, buf, buflen);
+ err = __nfs4_proc_set_acl(inode, buf, buflen, type);
trace_nfs4_set_acl(inode, err);
if (err == -NFS4ERR_BADOWNER || err == -NFS4ERR_BADNAME) {
/*
@@ -7659,19 +7680,19 @@ static int nfs4_xattr_set_nfs4_acl(const struct xattr_handler *handler,
const char *key, const void *buf,
size_t buflen, int flags)
{
- return nfs4_proc_set_acl(inode, buf, buflen);
+ return nfs4_proc_set_acl(inode, buf, buflen, NFS4ACL_ACL);
}

static int nfs4_xattr_get_nfs4_acl(const struct xattr_handler *handler,
struct dentry *unused, struct inode *inode,
const char *key, void *buf, size_t buflen)
{
- return nfs4_proc_get_acl(inode, buf, buflen);
+ return nfs4_proc_get_acl(inode, buf, buflen, NFS4ACL_ACL);
}

static bool nfs4_xattr_list_nfs4_acl(struct dentry *dentry)
{
- return nfs4_server_supports_acls(NFS_SERVER(d_inode(dentry)));
+ return nfs4_server_supports_acls(NFS_SB(dentry->d_sb), NFS4ACL_ACL);
}

#ifdef CONFIG_NFS_V4_SECURITY_LABEL
diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h
index 5662d8be04eb..8d04b6a5964c 100644
--- a/include/linux/nfs4.h
+++ b/include/linux/nfs4.h
@@ -451,6 +451,8 @@ enum lock_type4 {
#define FATTR4_WORD1_TIME_MODIFY (1UL << 21)
#define FATTR4_WORD1_TIME_MODIFY_SET (1UL << 22)
#define FATTR4_WORD1_MOUNTED_ON_FILEID (1UL << 23)
+#define FATTR4_WORD1_DACL (1UL << 26)
+#define FATTR4_WORD1_SACL (1UL << 27)
#define FATTR4_WORD1_FS_LAYOUT_TYPES (1UL << 30)
#define FATTR4_WORD2_LAYOUT_TYPES (1UL << 0)
#define FATTR4_WORD2_LAYOUT_BLKSIZE (1UL << 1)
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 2863e5a69c6a..13d068c57d8d 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -800,6 +800,13 @@ struct nfs_setattrargs {
const struct nfs4_label *label;
};

+enum nfs4_acl_type {
+ NFS4ACL_NONE = 0,
+ NFS4ACL_ACL,
+ NFS4ACL_DACL,
+ NFS4ACL_SACL,
+};
+
struct nfs_setaclargs {
struct nfs4_sequence_args seq_args;
struct nfs_fh * fh;
--
2.36.1