Version 2 upcalls will allow the nfsd to include a hash of the kerberos
principal string in the Cld_Create upcall. If a principal is present in
the svc_cred, then the hash will be included in the Cld_Create upcall.
We attempt to use the svc_cred.cr_raw_principal (which is returned by
gssproxy) first, and then fall back to using the svc_cred.cr_principal
(which is returned by both gssproxy and rpc.svcgssd). Upon a subsequent
restart, the hash will be returned in the Cld_Gracestart downcall and
stored in the reclaim_str_hashtbl so it can be used when handling
reclaim opens.
Signed-off-by: Scott Mayhew <smayhew@xxxxxxxxxx>
---
fs/nfsd/nfs4recover.c | 223 +++++++++++++++++++++++++++++++---
fs/nfsd/nfs4state.c | 6 +-
fs/nfsd/state.h | 3 +-
include/uapi/linux/nfsd/cld.h | 30 ++++-
4 files changed, 245 insertions(+), 17 deletions(-)
diff --git a/fs/nfsd/nfs4recover.c b/fs/nfsd/nfs4recover.c
index 58a61339d40c..cdc75ad4438b 100644
--- a/fs/nfsd/nfs4recover.c
+++ b/fs/nfsd/nfs4recover.c
@@ -64,6 +64,7 @@ struct nfsd4_client_tracking_ops {
};
static const struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops;
+static const struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops_v2;
/* Globals */
static char user_recovery_dirname[PATH_MAX] = "/var/lib/nfs/v4recovery";
@@ -177,6 +178,7 @@ __nfsd4_create_reclaim_record_grace(struct nfs4_client *clp,
const char *dname, int len, struct nfsd_net *nn)
{
struct xdr_netobj name;
+ struct xdr_netobj princhash = { .len = 0, .data = NULL };
struct nfs4_client_reclaim *crp;
name.data = kmemdup(dname, len, GFP_KERNEL);
@@ -186,7 +188,7 @@ __nfsd4_create_reclaim_record_grace(struct nfs4_client *clp,
return;
}
name.len = len;
- crp = nfs4_client_to_reclaim(name, nn);
+ crp = nfs4_client_to_reclaim(name, princhash, nn);
if (!crp) {
kfree(name.data);
return;
@@ -486,6 +488,7 @@ static int
load_recdir(struct dentry *parent, struct dentry *child, struct nfsd_net *nn)
{
struct xdr_netobj name;
+ struct xdr_netobj princhash = { .len = 0, .data = NULL };
if (child->d_name.len != HEXDIR_LEN - 1) {
printk("%s: illegal name %pd in recovery directory\n",
@@ -500,7 +503,7 @@ load_recdir(struct dentry *parent, struct dentry *child, struct nfsd_net *nn)
goto out;
}
name.len = HEXDIR_LEN;
- if (!nfs4_client_to_reclaim(name, nn))
+ if (!nfs4_client_to_reclaim(name, princhash, nn))
kfree(name.data);
out:
return 0;
@@ -737,6 +740,7 @@ struct cld_net {
struct list_head cn_list;
unsigned int cn_xid;
bool cn_has_legacy;
+ struct crypto_shash *cn_tfm;
};
struct cld_upcall {
@@ -746,6 +750,7 @@ struct cld_upcall {
union {
struct cld_msg_hdr cu_hdr;
struct cld_msg cu_msg;
+ struct cld_msg_v2 cu_msg_v2;
} cu_u;
};
@@ -792,11 +797,11 @@ cld_pipe_upcall(struct rpc_pipe *pipe, void *cmsg)
}
static ssize_t
-__cld_pipe_inprogress_downcall(const struct cld_msg __user *cmsg,
+__cld_pipe_inprogress_downcall(const struct cld_msg_v2 __user *cmsg,
struct nfsd_net *nn)
{
- uint8_t cmd;
- struct xdr_netobj name;
+ uint8_t cmd, princhashlen;
+ struct xdr_netobj name, princhash = { .len = 0, .data = NULL };
uint16_t namelen;
struct cld_net *cn = nn->cld_net;
@@ -805,19 +810,45 @@ __cld_pipe_inprogress_downcall(const struct cld_msg __user *cmsg,
return -EFAULT;
}
if (cmd == Cld_GraceStart) {
- if (get_user(namelen, &cmsg->cm_u.cm_name.cn_len))
- return -EFAULT;
- name.data = memdup_user(&cmsg->cm_u.cm_name.cn_id, namelen);
- if (IS_ERR_OR_NULL(name.data))
- return -EFAULT;
- name.len = namelen;
+ if (nn->client_tracking_ops->version >= 2) {
+ const struct cld_clntinfo __user *ci;
+
+ ci = &cmsg->cm_u.cm_clntinfo;
+ if (get_user(namelen, &ci->cc_name.cn_len))
+ return -EFAULT;
+ name.data = memdup_user(&ci->cc_name.cn_id, namelen);
+ if (IS_ERR_OR_NULL(name.data))
+ return -EFAULT;
+ name.len = namelen;
+ get_user(princhashlen, &ci->cc_princhash.cp_len);
+ if (princhashlen > 0) {
+ princhash.data = memdup_user(
+ &ci->cc_princhash.cp_data,
+ princhashlen);
+ if (IS_ERR_OR_NULL(princhash.data))
+ return -EFAULT;
+ princhash.len = princhashlen;
+ } else
+ princhash.len = 0;
+ } else {
+ const struct cld_name __user *cnm;
+
+ cnm = &cmsg->cm_u.cm_name;
+ if (get_user(namelen, &cnm->cn_len))
+ return -EFAULT;
+ name.data = memdup_user(&cnm->cn_id, namelen);
+ if (IS_ERR_OR_NULL(name.data))
+ return -EFAULT;
+ name.len = namelen;
+ }
if (name.len > 5 && memcmp(name.data, "hash:", 5) == 0) {
name.len = name.len - 5;
memmove(name.data, name.data + 5, name.len);
cn->cn_has_legacy = true;
}
- if (!nfs4_client_to_reclaim(name, nn)) {
+ if (!nfs4_client_to_reclaim(name, princhash, nn)) {
kfree(name.data);
+ kfree(princhash.data);
return -EFAULT;
}
return nn->client_tracking_ops->msglen;
@@ -830,7 +861,7 @@ cld_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
{
struct cld_upcall *tmp, *cup;
struct cld_msg_hdr __user *hdr = (struct cld_msg_hdr __user *)src;
- struct cld_msg __user *cmsg = (struct cld_msg __user *)src;
+ struct cld_msg_v2 __user *cmsg = (struct cld_msg_v2 __user *)src;
uint32_t xid;
struct nfsd_net *nn = net_generic(file_inode(filp)->i_sb->s_fs_info,
nfsd_net_id);
@@ -881,7 +912,7 @@ cld_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
if (status == -EINPROGRESS)
return __cld_pipe_inprogress_downcall(cmsg, nn);
- if (copy_from_user(&cup->cu_u.cu_msg, src, mlen) != 0)
+ if (copy_from_user(&cup->cu_u.cu_msg_v2, src, mlen) != 0)
return -EFAULT;
complete(&cup->cu_done);
@@ -1019,6 +1050,8 @@ nfsd4_remove_cld_pipe(struct net *net)
nfsd4_cld_unregister_net(net, cn->cn_pipe);
rpc_destroy_pipe_data(cn->cn_pipe);
+ if (cn->cn_tfm)
+ crypto_free_shash(cn->cn_tfm);
kfree(nn->cld_net);
nn->cld_net = NULL;
}
@@ -1103,6 +1136,75 @@ nfsd4_cld_create(struct nfs4_client *clp)
"record on stable storage: %d\n", ret);
}
+/* Ask daemon to create a new record */
+static void
+nfsd4_cld_create_v2(struct nfs4_client *clp)
+{
+ int ret;
+ struct cld_upcall *cup;
+ struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
+ struct cld_net *cn = nn->cld_net;
+ struct cld_msg_v2 *cmsg;
+ struct crypto_shash *tfm = cn->cn_tfm;
+ struct xdr_netobj cksum;
+ char *principal = NULL;
+ SHASH_DESC_ON_STACK(desc, tfm);
+
+ /* Don't upcall if it's already stored */
+ if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
+ return;
+
+ cup = alloc_cld_upcall(nn);
+ if (!cup) {
+ ret = -ENOMEM;
+ goto out_err;
+ }
+
+ cmsg = &cup->cu_u.cu_msg_v2;
+ cmsg->cm_cmd = Cld_Create;
+ cmsg->cm_u.cm_clntinfo.cc_name.cn_len = clp->cl_name.len;
+ memcpy(cmsg->cm_u.cm_clntinfo.cc_name.cn_id, clp->cl_name.data,
+ clp->cl_name.len);
+ if (clp->cl_cred.cr_raw_principal)
+ principal = clp->cl_cred.cr_raw_principal;
+ else if (clp->cl_cred.cr_principal)
+ principal = clp->cl_cred.cr_principal;
+ if (principal) {
+ desc->tfm = tfm;
+ cksum.len = crypto_shash_digestsize(tfm);
+ cksum.data = kmalloc(cksum.len, GFP_KERNEL);
+ if (cksum.data == NULL) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ ret = crypto_shash_digest(desc, principal, strlen(principal),
+ cksum.data);
+ shash_desc_zero(desc);
+ if (ret) {
+ kfree(cksum.data);
+ goto out;
+ }
+ cmsg->cm_u.cm_clntinfo.cc_princhash.cp_len = cksum.len;
+ memcpy(cmsg->cm_u.cm_clntinfo.cc_princhash.cp_data,
+ cksum.data, cksum.len);
+ kfree(cksum.data);
+ } else
+ cmsg->cm_u.cm_clntinfo.cc_princhash.cp_len = 0;
+
+ ret = cld_pipe_upcall(cn->cn_pipe, cmsg);
+ if (!ret) {
+ ret = cmsg->cm_status;
+ set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
+ }
+
+out:
+ free_cld_upcall(cup);
+out_err:
+ if (ret)
+ pr_err("NFSD: Unable to create client record on stable storage: %d\n",
+ ret);
+}
+
/* Ask daemon to create a new record */
static void
nfsd4_cld_remove(struct nfs4_client *clp)
@@ -1229,6 +1331,79 @@ nfsd4_cld_check(struct nfs4_client *clp)
return 0;
}
+static int
+nfsd4_cld_check_v2(struct nfs4_client *clp)
+{
+ struct nfs4_client_reclaim *crp;
+ struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
+ struct cld_net *cn = nn->cld_net;
+ int status;
+ char dname[HEXDIR_LEN];
+ struct xdr_netobj name;
+ struct crypto_shash *tfm = cn->cn_tfm;
+ struct xdr_netobj cksum;
+ char *principal = NULL;
+ SHASH_DESC_ON_STACK(desc, tfm);
+
+ /* did we already find that this client is stable? */
+ if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
+ return 0;
+
+ /* look for it in the reclaim hashtable otherwise */
+ crp = nfsd4_find_reclaim_client(clp->cl_name, nn);
+ if (crp)
+ goto found;
+
+ if (cn->cn_has_legacy) {
+ status = nfs4_make_rec_clidname(dname, &clp->cl_name);
+ if (status)
+ return -ENOENT;
+
+ name.data = kmemdup(dname, HEXDIR_LEN, GFP_KERNEL);
+ if (!name.data) {
+ dprintk("%s: failed to allocate memory for name.data\n",
+ __func__);
+ return -ENOENT;
+ }
+ name.len = HEXDIR_LEN;
+ crp = nfsd4_find_reclaim_client(name, nn);
+ kfree(name.data);
+ if (crp)
+ goto found;
+
+ }
+ return -ENOENT;
+found:
+ if (crp->cr_princhash.len) {
+ if (clp->cl_cred.cr_raw_principal)
+ principal = clp->cl_cred.cr_raw_principal;
+ else if (clp->cl_cred.cr_principal)
+ principal = clp->cl_cred.cr_principal;
+ if (principal == NULL)
+ return -ENOENT;
+ desc->tfm = tfm;
+ cksum.len = crypto_shash_digestsize(tfm);
+ cksum.data = kmalloc(cksum.len, GFP_KERNEL);
+ if (cksum.data == NULL)
+ return -ENOENT;
+ status = crypto_shash_digest(desc, principal, strlen(principal),
+ cksum.data);
+ shash_desc_zero(desc);
+ if (status) {
+ kfree(cksum.data);
+ return -ENOENT;
+ }
+ if (memcmp(crp->cr_princhash.data, cksum.data,
+ crp->cr_princhash.len)) {
+ kfree(cksum.data);
+ return -ENOENT;
+ }
+ kfree(cksum.data);
+ }
+ crp->cr_clp = clp;
+ return 0;
+}
+
static int
nfsd4_cld_grace_start(struct nfsd_net *nn)
{
@@ -1380,6 +1555,9 @@ nfsd4_cld_get_version(struct nfsd_net *nn)
case 1:
nn->client_tracking_ops = &nfsd4_cld_tracking_ops;
break;
+ case 2:
+ nn->client_tracking_ops = &nfsd4_cld_tracking_ops_v2;
+ break;
default:
break;
}
@@ -1408,6 +1586,11 @@ nfsd4_cld_tracking_init(struct net *net)
status = __nfsd4_init_cld_pipe(net);
if (status)
goto err_shutdown;
+ nn->cld_net->cn_tfm = crypto_alloc_shash("sha256", 0, 0);
+ if (IS_ERR(nn->cld_net->cn_tfm)) {
+ status = PTR_ERR(nn->cld_net->cn_tfm);
+ goto err_remove;
+ }
/*
* rpc pipe upcalls take 30 seconds to time out, so we don't want to
@@ -1480,6 +1663,18 @@ static const struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops = {
.msglen = sizeof(struct cld_msg),
};
+/* v2 create/check ops include the principal, if available */
+static const struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops_v2 = {
+ .init = nfsd4_cld_tracking_init,
+ .exit = nfsd4_cld_tracking_exit,
+ .create = nfsd4_cld_create_v2,
+ .remove = nfsd4_cld_remove,
+ .check = nfsd4_cld_check_v2,
+ .grace_done = nfsd4_cld_grace_done,
+ .version = 2,
+ .msglen = sizeof(struct cld_msg_v2),
+};
+
/* upcall via usermodehelper */
static char cltrack_prog[PATH_MAX] = "/sbin/nfsdcltrack";
module_param_string(cltrack_prog, cltrack_prog, sizeof(cltrack_prog),
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 7857942c5ca6..a744546535bc 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -6888,7 +6888,8 @@ nfs4_has_reclaimed_state(struct xdr_netobj name, struct nfsd_net *nn)
* will be freed in nfs4_remove_reclaim_record in the normal case).
*/
struct nfs4_client_reclaim *
-nfs4_client_to_reclaim(struct xdr_netobj name, struct nfsd_net *nn)
+nfs4_client_to_reclaim(struct xdr_netobj name, struct xdr_netobj princhash,
+ struct nfsd_net *nn)
{
unsigned int strhashval;
struct nfs4_client_reclaim *crp;
@@ -6901,6 +6902,8 @@ nfs4_client_to_reclaim(struct xdr_netobj name, struct nfsd_net *nn)
list_add(&crp->cr_strhash, &nn->reclaim_str_hashtbl[strhashval]);
crp->cr_name.data = name.data;
crp->cr_name.len = name.len;
+ crp->cr_princhash.data = princhash.data;
+ crp->cr_princhash.len = princhash.len;
crp->cr_clp = NULL;
nn->reclaim_str_hashtbl_size++;
}
@@ -6912,6 +6915,7 @@ nfs4_remove_reclaim_record(struct nfs4_client_reclaim *crp, struct nfsd_net *nn)
{
list_del(&crp->cr_strhash);
kfree(crp->cr_name.data);
+ kfree(crp->cr_princhash.data);
kfree(crp);
nn->reclaim_str_hashtbl_size--;
}
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 5dbd16946e8e..d84e1ef70b44 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -378,6 +378,7 @@ struct nfs4_client_reclaim {
struct list_head cr_strhash; /* hash by cr_name */
struct nfs4_client *cr_clp; /* pointer to associated clp */
struct xdr_netobj cr_name; /* recovery dir name */
+ struct xdr_netobj cr_princhash;
};
/* A reasonable value for REPLAY_ISIZE was estimated as follows:
@@ -645,7 +646,7 @@ extern void nfsd4_shutdown_callback(struct nfs4_client *);
extern void nfsd4_shutdown_copy(struct nfs4_client *clp);
extern void nfsd4_prepare_cb_recall(struct nfs4_delegation *dp);
extern struct nfs4_client_reclaim *nfs4_client_to_reclaim(struct xdr_netobj name,
- struct nfsd_net *nn);
+ struct xdr_netobj princhash, struct nfsd_net *nn);
extern bool nfs4_has_reclaimed_state(struct xdr_netobj name, struct nfsd_net *nn);
struct nfs4_file *find_file(struct knfsd_fh *fh);
diff --git a/include/uapi/linux/nfsd/cld.h b/include/uapi/linux/nfsd/cld.h
index c5aad16d10c0..a519313af953 100644
--- a/include/uapi/linux/nfsd/cld.h
+++ b/include/uapi/linux/nfsd/cld.h
@@ -26,11 +26,15 @@
#include <linux/types.h>
/* latest upcall version available */
-#define CLD_UPCALL_VERSION 1
+#define CLD_UPCALL_VERSION 2
/* defined by RFC3530 */
#define NFS4_OPAQUE_LIMIT 1024
+#ifndef SHA256_DIGEST_SIZE
+#define SHA256_DIGEST_SIZE 32
+#endif
+
enum cld_command {
Cld_Create, /* create a record for this cm_id */
Cld_Remove, /* remove record of this cm_id */
@@ -46,6 +50,17 @@ struct cld_name {
unsigned char cn_id[NFS4_OPAQUE_LIMIT]; /* client-provided */
} __attribute__((packed));
+/* sha256 hash of the kerberos principal */
+struct cld_princhash {
+ __u8 cp_len; /* length of cp_data */
+ unsigned char cp_data[SHA256_DIGEST_SIZE]; /* hash of principal */
+} __attribute__((packed));
+
+struct cld_clntinfo {
+ struct cld_name cc_name;
+ struct cld_princhash cc_princhash;
+} __attribute__((packed));
+
/* message struct for communication with userspace */
struct cld_msg {
__u8 cm_vers; /* upcall version */
@@ -59,6 +74,19 @@ struct cld_msg {
} __attribute__((packed)) cm_u;
} __attribute__((packed));
+/* version 2 message can include hash of kerberos principal */
+struct cld_msg_v2 {
+ __u8 cm_vers; /* upcall version */
+ __u8 cm_cmd; /* upcall command */
+ __s16 cm_status; /* return code */
+ __u32 cm_xid; /* transaction id */
+ union {
+ struct cld_name cm_name;
+ __u8 cm_version; /* for getting max version */
+ struct cld_clntinfo cm_clntinfo; /* name & princ hash */
+ } __attribute__((packed)) cm_u;
+} __attribute__((packed));
+
struct cld_msg_hdr {
__u8 cm_vers; /* upcall version */
__u8 cm_cmd; /* upcall command */
--
2.17.2
