On Aug 5, 2013, at 4:26 PM, Weston Andros Adamson <dros@xxxxxxxxxx> wrote:
> This is a minimal client side implementation of SP4_MACH_CRED. It will
> attempt to negotiate SP4_MACH_CRED iff the EXCHANGE_ID is using
> krb5i or krb5p auth. SP4_MACH_CRED will be used if the server supports the
> minimal operations:
>
> BACKCHANNEL_CTL
> BIND_CONN_TO_SESSION
> CREATE_SESSION
> DESTROY_SESSION
> DESTROY_CLIENTID
>
> This implementation only includes the EXCHANGE_ID negotiation code because
> the client will already use the machine cred for these operations.
>
> This patch also lays the groundwork for adding more SP4_MACH_CRED "features" -
> instead of just using SP4_MACH_CRED wherever the server says it's ok, we will
> make sure that appropriate sets of operations are supported in the initial
> negotiation and then only use these negotiated features. The hope is that this
> will limit the scope of testing.
>
> Signed-off-by: Weston Andros Adamson <dros@xxxxxxxxxx>
> ---
>
> Version 2: fixed a couple of comment typos and a style cleanup
>
> fs/nfs/nfs4proc.c | 115 +++++++++++++++++++++++++++++++++++++++++++---
> fs/nfs/nfs4xdr.c | 73 +++++++++++++++++++++++++----
> include/linux/nfs_fs_sb.h | 4 ++
> include/linux/nfs_xdr.h | 19 ++++++++
> 4 files changed, 194 insertions(+), 17 deletions(-)
>
> diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
> index 0e64ccc..2564d1b 100644
> --- a/fs/nfs/nfs4proc.c
> +++ b/fs/nfs/nfs4proc.c
> @@ -5915,16 +5915,63 @@ out:
> }
>
> /*
> - * nfs4_proc_exchange_id()
> + * Minimum set of SP4_MACH_CRED operations from RFC 5661
> + */
> +static uint32_t _nfs4_spo_must_enforce[NFS4_OP_MAP_NUM_WORDS] = {
> + [1] = 1 << (OP_BIND_CONN_TO_SESSION - 32) |
> + 1 << (OP_EXCHANGE_ID - 32) |
> + 1 << (OP_CREATE_SESSION - 32) |
> + 1 << (OP_DESTROY_SESSION - 32) |
> + 1 << (OP_DESTROY_CLIENTID - 32)
> +};
This should be const - I'll repost once I get comments.
-dros
> +
> +/*
> + * Select the state protection mode for client `clp' given the server results
> + * from exchange_id in `sp'.
> *
> - * Returns zero, a negative errno, or a negative NFS4ERR status code.
> + * Returns 0 on success, negative errno otherwise.
> + */
> +static int _nfs4_sp4_select_mode(struct nfs_client *clp,
> + struct nfs41_state_protection *sp)
> +{
> + unsigned int i;
> +
> + if (sp->how == SP4_MACH_CRED) {
> + /* Print state protect result */
> + dfprintk(MOUNT, "Server SP4_MACH_CRED support:\n");
> + for (i = 0; i <= LAST_NFS4_OP; i++) {
> + if (test_bit(i, sp->enforce.u.longs))
> + dfprintk(MOUNT, " enforce op %d\n", i);
> + if (test_bit(i, sp->allow.u.longs))
> + dfprintk(MOUNT, " allow op %d\n", i);
> + }
> +
> + /*
> + * Minimal mode - state operations are allowed to use machine
> + * credential. Note this already happens by default, so the
> + * client doesn't have to do anything more than the negotiation.
> + */
> + if (memcmp(sp->enforce.u.words, _nfs4_spo_must_enforce,
> + sizeof(sp->enforce.u.words)) == 0)
> + set_bit(NFS_SP4_MACH_CRED_MINIMAL, &clp->cl_sp4_flags);
> +
> + if (!clp->cl_sp4_flags) {
> + dfprintk(MOUNT, "sp4_mach_cred: disabled\n");
> + return -EINVAL;
> + } else
> + dfprintk(MOUNT, "sp4_mach_cred: enabled\n");
> + }
> +
> + return 0;
> +}
> +
> +/*
> + * _nfs4_proc_exchange_id()
> *
> - * Since the clientid has expired, all compounds using sessions
> - * associated with the stale clientid will be returning
> - * NFS4ERR_BADSESSION in the sequence operation, and will therefore
> - * be in some phase of session reset.
> + * Wrapper for EXCHANGE_ID operation.
> */
> -int nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred)
> +static int _nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred,
> + u32 sp4_how)
> {
> nfs4_verifier verifier;
> struct nfs41_exchange_id_args args = {
> @@ -5971,10 +6018,35 @@ int nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred)
> goto out_server_scope;
> }
>
> + switch (sp4_how) {
> + case SP4_NONE:
> + args.state_protect.how = SP4_NONE;
> + break;
> +
> + case SP4_MACH_CRED:
> + args.state_protect.how = SP4_MACH_CRED;
> +
> + /* request minumum set of operations */
> + memcpy(args.state_protect.enforce.u.words,
> + &_nfs4_spo_must_enforce,
> + sizeof(uint32_t) * NFS4_OP_MAP_NUM_WORDS);
> +
> + break;
> +
> + default:
> + /* unsupported! */
> + WARN_ON_ONCE(1);
> + status = -EINVAL;
> + goto out_server_scope;
> + }
> +
> status = rpc_call_sync(clp->cl_rpcclient, &msg, RPC_TASK_TIMEOUT);
> if (status == 0)
> status = nfs4_check_cl_exchange_flags(res.flags);
>
> + if (status == 0)
> + status = _nfs4_sp4_select_mode(clp, &res.state_protect);
> +
> if (status == 0) {
> clp->cl_clientid = res.clientid;
> clp->cl_exchange_flags = (res.flags & ~EXCHGID4_FLAG_CONFIRMED_R);
> @@ -6021,6 +6093,35 @@ out:
> return status;
> }
>
> +/*
> + * nfs4_proc_exchange_id()
> + *
> + * Returns zero, a negative errno, or a negative NFS4ERR status code.
> + *
> + * Since the clientid has expired, all compounds using sessions
> + * associated with the stale clientid will be returning
> + * NFS4ERR_BADSESSION in the sequence operation, and will therefore
> + * be in some phase of session reset.
> + *
> + * Will attempt to negotiate SP4_MACH_CRED if krb5i / krb5p auth is used.
> + */
> +int nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred)
> +{
> + rpc_authflavor_t authflavor = clp->cl_rpcclient->cl_auth->au_flavor;
> + int status;
> +
> + /* try SP4_MACH_CRED if krb5i/p */
> + if (authflavor == RPC_AUTH_GSS_KRB5I ||
> + authflavor == RPC_AUTH_GSS_KRB5P) {
> + status = _nfs4_proc_exchange_id(clp, cred, SP4_MACH_CRED);
> + if (!status)
> + return 0;
> + }
> +
> + /* try SP4_NONE */
> + return _nfs4_proc_exchange_id(clp, cred, SP4_NONE);
> +}
> +
> static int _nfs4_proc_destroy_clientid(struct nfs_client *clp,
> struct rpc_cred *cred)
> {
> diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
> index 1a4a3bd..0a645f7 100644
> --- a/fs/nfs/nfs4xdr.c
> +++ b/fs/nfs/nfs4xdr.c
> @@ -294,7 +294,9 @@ static int nfs4_stat_to_errno(int);
> XDR_QUADLEN(NFS4_EXCHANGE_ID_LEN) + \
> 1 /* flags */ + \
> 1 /* spa_how */ + \
> - 0 /* SP4_NONE (for now) */ + \
> + /* max is SP4_MACH_CRED (for now) */ + \
> + 1 + NFS4_OP_MAP_NUM_WORDS + \
> + 1 + NFS4_OP_MAP_NUM_WORDS + \
> 1 /* implementation id array of size 1 */ + \
> 1 /* nii_domain */ + \
> XDR_QUADLEN(NFS4_OPAQUE_LIMIT) + \
> @@ -306,7 +308,9 @@ static int nfs4_stat_to_errno(int);
> 1 /* eir_sequenceid */ + \
> 1 /* eir_flags */ + \
> 1 /* spr_how */ + \
> - 0 /* SP4_NONE (for now) */ + \
> + /* max is SP4_MACH_CRED (for now) */ + \
> + 1 + NFS4_OP_MAP_NUM_WORDS + \
> + 1 + NFS4_OP_MAP_NUM_WORDS + \
> 2 /* eir_server_owner.so_minor_id */ + \
> /* eir_server_owner.so_major_id<> */ \
> XDR_QUADLEN(NFS4_OPAQUE_LIMIT) + 1 + \
> @@ -1726,6 +1730,14 @@ static void encode_bind_conn_to_session(struct xdr_stream *xdr,
> *p = 0; /* use_conn_in_rdma_mode = False */
> }
>
> +static void encode_op_map(struct xdr_stream *xdr, struct nfs4_op_map *op_map)
> +{
> + unsigned int i;
> + encode_uint32(xdr, NFS4_OP_MAP_NUM_WORDS);
> + for (i = 0; i < NFS4_OP_MAP_NUM_WORDS; i++)
> + encode_uint32(xdr, op_map->u.words[i]);
> +}
> +
> static void encode_exchange_id(struct xdr_stream *xdr,
> struct nfs41_exchange_id_args *args,
> struct compound_hdr *hdr)
> @@ -1739,9 +1751,19 @@ static void encode_exchange_id(struct xdr_stream *xdr,
>
> encode_string(xdr, args->id_len, args->id);
>
> - p = reserve_space(xdr, 12);
> - *p++ = cpu_to_be32(args->flags);
> - *p++ = cpu_to_be32(0); /* zero length state_protect4_a */
> + encode_uint32(xdr, args->flags);
> + encode_uint32(xdr, args->state_protect.how);
> +
> + switch (args->state_protect.how) {
> + case SP4_NONE:
> + break;
> + case SP4_MACH_CRED:
> + encode_op_map(xdr, &args->state_protect.enforce);
> + encode_op_map(xdr, &args->state_protect.allow);
> + break;
> + default:
> + BUG();
> + }
>
> if (send_implementation_id &&
> sizeof(CONFIG_NFS_V4_1_IMPLEMENTATION_ID_DOMAIN) > 1 &&
> @@ -1752,7 +1774,7 @@ static void encode_exchange_id(struct xdr_stream *xdr,
> utsname()->version, utsname()->machine);
>
> if (len > 0) {
> - *p = cpu_to_be32(1); /* implementation id array length=1 */
> + encode_uint32(xdr, 1); /* implementation id array length=1 */
>
> encode_string(xdr,
> sizeof(CONFIG_NFS_V4_1_IMPLEMENTATION_ID_DOMAIN) - 1,
> @@ -1763,7 +1785,7 @@ static void encode_exchange_id(struct xdr_stream *xdr,
> p = xdr_encode_hyper(p, 0);
> *p = cpu_to_be32(0);
> } else
> - *p = cpu_to_be32(0); /* implementation id array length=0 */
> + encode_uint32(xdr, 0); /* implementation id array length=0 */
> }
>
> static void encode_create_session(struct xdr_stream *xdr,
> @@ -5375,6 +5397,23 @@ static int decode_secinfo_no_name(struct xdr_stream *xdr, struct nfs4_secinfo_re
> return decode_secinfo_common(xdr, res);
> }
>
> +static int decode_op_map(struct xdr_stream *xdr, struct nfs4_op_map *op_map)
> +{
> + __be32 *p;
> + uint32_t bitmap_words;
> + unsigned int i;
> +
> + p = xdr_inline_decode(xdr, 4);
> + bitmap_words = be32_to_cpup(p++);
> + if (bitmap_words > NFS4_OP_MAP_NUM_WORDS)
> + return -EIO;
> + p = xdr_inline_decode(xdr, 4 * bitmap_words);
> + for (i = 0; i < bitmap_words; i++)
> + op_map->u.words[i] = be32_to_cpup(p++);
> +
> + return 0;
> +}
> +
> static int decode_exchange_id(struct xdr_stream *xdr,
> struct nfs41_exchange_id_res *res)
> {
> @@ -5398,10 +5437,24 @@ static int decode_exchange_id(struct xdr_stream *xdr,
> res->seqid = be32_to_cpup(p++);
> res->flags = be32_to_cpup(p++);
>
> - /* We ask for SP4_NONE */
> - dummy = be32_to_cpup(p);
> - if (dummy != SP4_NONE)
> + res->state_protect.how = be32_to_cpup(p);
> + switch (res->state_protect.how) {
> + case SP4_NONE:
> + break;
> + case SP4_MACH_CRED:
> + status = decode_op_map(xdr, &res->state_protect.enforce);
> + if (status)
> + return status;
> + status = decode_op_map(xdr, &res->state_protect.allow);
> + if (status)
> + return status;
> + break;
> + default:
> + /* completely unexpected since we only ever ask for SP_NONE or
> + * SP4_MACH_CRED */
> + WARN_ON_ONCE(1);
> return -EIO;
> + }
>
> /* server_owner4.so_minor_id */
> p = xdr_inline_decode(xdr, 8);
> diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
> index d221243..a0af429 100644
> --- a/include/linux/nfs_fs_sb.h
> +++ b/include/linux/nfs_fs_sb.h
> @@ -87,6 +87,10 @@ struct nfs_client {
> struct nfs41_server_owner *cl_serverowner;
> struct nfs41_server_scope *cl_serverscope;
> struct nfs41_impl_id *cl_implid;
> + /* nfs 4.1+ state protection modes: */
> + unsigned long cl_sp4_flags;
> +#define NFS_SP4_MACH_CRED_MINIMAL 1 /* Minimal sp4_mach_cred - state ops
> + * must use machine cred */
> #endif /* CONFIG_NFS_V4 */
>
> #ifdef CONFIG_NFS_FSCACHE
> diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
> index 8651574..18681d9 100644
> --- a/include/linux/nfs_xdr.h
> +++ b/include/linux/nfs_xdr.h
> @@ -1107,6 +1107,23 @@ struct pnfs_ds_commit_info {
> struct pnfs_commit_bucket *buckets;
> };
>
> +#define NFS4_OP_MAP_NUM_LONGS \
> + DIV_ROUND_UP(LAST_NFS4_OP, 8 * sizeof(unsigned long))
> +#define NFS4_OP_MAP_NUM_WORDS \
> + (NFS4_OP_MAP_NUM_LONGS * sizeof(unsigned long) / sizeof(u32))
> +struct nfs4_op_map {
> + union {
> + unsigned long longs[NFS4_OP_MAP_NUM_LONGS];
> + u32 words[NFS4_OP_MAP_NUM_WORDS];
> + } u;
> +};
> +
> +struct nfs41_state_protection {
> + u32 how;
> + struct nfs4_op_map enforce;
> + struct nfs4_op_map allow;
> +};
> +
> #define NFS4_EXCHANGE_ID_LEN (48)
> struct nfs41_exchange_id_args {
> struct nfs_client *client;
> @@ -1114,6 +1131,7 @@ struct nfs41_exchange_id_args {
> unsigned int id_len;
> char id[NFS4_EXCHANGE_ID_LEN];
> u32 flags;
> + struct nfs41_state_protection state_protect;
> };
>
> struct nfs41_server_owner {
> @@ -1146,6 +1164,7 @@ struct nfs41_exchange_id_res {
> struct nfs41_server_owner *server_owner;
> struct nfs41_server_scope *server_scope;
> struct nfs41_impl_id *impl_id;
> + struct nfs41_state_protection state_protect;
> };
>
> struct nfs41_create_session_args {
> --
> 1.7.12.4 (Apple Git-37)
>
--
To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
