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authorWeston Andros Adamson <dros@netapp.com>2013-10-18 15:15:19 -0400
committerTrond Myklebust <Trond.Myklebust@netapp.com>2013-10-28 15:38:02 -0400
commit4d4b69dd847a098cdca341c45326f6c6f61b8691 (patch)
treefdd1d7204d48f7af1f93f06844ee507e36dc917b /fs/nfs/super.c
parent5837f6dfcb00f764976ddc178933e612702cbf54 (diff)
downloadlinux-4d4b69dd847a098cdca341c45326f6c6f61b8691.tar.bz2
NFS: add support for multiple sec= mount options
This patch adds support for multiple security options which can be specified using a colon-delimited list of security flavors (the same syntax as nfsd's exports file). This is useful, for instance, when NFSv4.x mounts cross SECINFO boundaries. With this patch a user can use "sec=krb5i,krb5p" to mount a remote filesystem using krb5i, but can still cross into krb5p-only exports. New mounts will try all security options before failing. NFSv4.x SECINFO results will be compared against the sec= flavors to find the first flavor in both lists or if no match is found will return -EPERM. Signed-off-by: Weston Andros Adamson <dros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Diffstat (limited to 'fs/nfs/super.c')
-rw-r--r--fs/nfs/super.c160
1 files changed, 105 insertions, 55 deletions
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 3a4f8bf5e5a5..317d6fc2160e 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -497,7 +497,8 @@ static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
static const struct {
rpc_authflavor_t flavour;
const char *str;
- } sec_flavours[] = {
+ } sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = {
+ /* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */
{ RPC_AUTH_NULL, "null" },
{ RPC_AUTH_UNIX, "sys" },
{ RPC_AUTH_GSS_KRB5, "krb5" },
@@ -1019,6 +1020,52 @@ static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
}
/*
+ * Add 'flavor' to 'auth_info' if not already present.
+ * Returns true if 'flavor' ends up in the list, false otherwise
+ */
+static bool nfs_auth_info_add(struct nfs_auth_info *auth_info,
+ rpc_authflavor_t flavor)
+{
+ unsigned int i;
+ unsigned int max_flavor_len = (sizeof(auth_info->flavors) /
+ sizeof(auth_info->flavors[0]));
+
+ /* make sure this flavor isn't already in the list */
+ for (i = 0; i < auth_info->flavor_len; i++) {
+ if (flavor == auth_info->flavors[i])
+ return true;
+ }
+
+ if (auth_info->flavor_len + 1 >= max_flavor_len) {
+ dfprintk(MOUNT, "NFS: too many sec= flavors\n");
+ return false;
+ }
+
+ auth_info->flavors[auth_info->flavor_len++] = flavor;
+ return true;
+}
+
+/*
+ * Return true if 'match' is in auth_info or auth_info is empty.
+ * Return false otherwise.
+ */
+bool nfs_auth_info_match(const struct nfs_auth_info *auth_info,
+ rpc_authflavor_t match)
+{
+ int i;
+
+ if (!auth_info->flavor_len)
+ return true;
+
+ for (i = 0; i < auth_info->flavor_len; i++) {
+ if (auth_info->flavors[i] == match)
+ return true;
+ }
+ return false;
+}
+EXPORT_SYMBOL_GPL(nfs_auth_info_match);
+
+/*
* Parse the value of the 'sec=' option.
*/
static int nfs_parse_security_flavors(char *value,
@@ -1026,49 +1073,55 @@ static int nfs_parse_security_flavors(char *value,
{
substring_t args[MAX_OPT_ARGS];
rpc_authflavor_t pseudoflavor;
+ char *p;
dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
- switch (match_token(value, nfs_secflavor_tokens, args)) {
- case Opt_sec_none:
- pseudoflavor = RPC_AUTH_NULL;
- break;
- case Opt_sec_sys:
- pseudoflavor = RPC_AUTH_UNIX;
- break;
- case Opt_sec_krb5:
- pseudoflavor = RPC_AUTH_GSS_KRB5;
- break;
- case Opt_sec_krb5i:
- pseudoflavor = RPC_AUTH_GSS_KRB5I;
- break;
- case Opt_sec_krb5p:
- pseudoflavor = RPC_AUTH_GSS_KRB5P;
- break;
- case Opt_sec_lkey:
- pseudoflavor = RPC_AUTH_GSS_LKEY;
- break;
- case Opt_sec_lkeyi:
- pseudoflavor = RPC_AUTH_GSS_LKEYI;
- break;
- case Opt_sec_lkeyp:
- pseudoflavor = RPC_AUTH_GSS_LKEYP;
- break;
- case Opt_sec_spkm:
- pseudoflavor = RPC_AUTH_GSS_SPKM;
- break;
- case Opt_sec_spkmi:
- pseudoflavor = RPC_AUTH_GSS_SPKMI;
- break;
- case Opt_sec_spkmp:
- pseudoflavor = RPC_AUTH_GSS_SPKMP;
- break;
- default:
- return 0;
+ while ((p = strsep(&value, ":")) != NULL) {
+ switch (match_token(p, nfs_secflavor_tokens, args)) {
+ case Opt_sec_none:
+ pseudoflavor = RPC_AUTH_NULL;
+ break;
+ case Opt_sec_sys:
+ pseudoflavor = RPC_AUTH_UNIX;
+ break;
+ case Opt_sec_krb5:
+ pseudoflavor = RPC_AUTH_GSS_KRB5;
+ break;
+ case Opt_sec_krb5i:
+ pseudoflavor = RPC_AUTH_GSS_KRB5I;
+ break;
+ case Opt_sec_krb5p:
+ pseudoflavor = RPC_AUTH_GSS_KRB5P;
+ break;
+ case Opt_sec_lkey:
+ pseudoflavor = RPC_AUTH_GSS_LKEY;
+ break;
+ case Opt_sec_lkeyi:
+ pseudoflavor = RPC_AUTH_GSS_LKEYI;
+ break;
+ case Opt_sec_lkeyp:
+ pseudoflavor = RPC_AUTH_GSS_LKEYP;
+ break;
+ case Opt_sec_spkm:
+ pseudoflavor = RPC_AUTH_GSS_SPKM;
+ break;
+ case Opt_sec_spkmi:
+ pseudoflavor = RPC_AUTH_GSS_SPKMI;
+ break;
+ case Opt_sec_spkmp:
+ pseudoflavor = RPC_AUTH_GSS_SPKMP;
+ break;
+ default:
+ dfprintk(MOUNT,
+ "NFS: sec= option '%s' not recognized\n", p);
+ return 0;
+ }
+
+ if (!nfs_auth_info_add(&mnt->auth_info, pseudoflavor))
+ return 0;
}
- mnt->auth_info.flavors[0] = pseudoflavor;
- mnt->auth_info.flavor_len = 1;
return 1;
}
@@ -1615,12 +1668,14 @@ out_security_failure:
}
/*
- * Ensure that the specified authtype in args->auth_info is supported by
- * the server. Returns 0 if it's ok, and -EACCES if not.
+ * Ensure that a specified authtype in args->auth_info is supported by
+ * the server. Returns 0 and sets args->selected_flavor if it's ok, and
+ * -EACCES if not.
*/
-static int nfs_verify_authflavor(struct nfs_parsed_mount_data *args,
+static int nfs_verify_authflavors(struct nfs_parsed_mount_data *args,
rpc_authflavor_t *server_authlist, unsigned int count)
{
+ rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
unsigned int i;
/*
@@ -1632,17 +1687,19 @@ static int nfs_verify_authflavor(struct nfs_parsed_mount_data *args,
* can be used.
*/
for (i = 0; i < count; i++) {
- if (args->auth_info.flavors[0] == server_authlist[i] ||
- server_authlist[i] == RPC_AUTH_NULL)
+ flavor = server_authlist[i];
+
+ if (nfs_auth_info_match(&args->auth_info, flavor) ||
+ flavor == RPC_AUTH_NULL)
goto out;
}
- dfprintk(MOUNT, "NFS: auth flavor %u not supported by server\n",
- args->auth_info.flavors[0]);
+ dfprintk(MOUNT,
+ "NFS: specified auth flavors not supported by server\n");
return -EACCES;
out:
- args->selected_flavor = args->auth_info.flavors[0];
+ args->selected_flavor = flavor;
dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->selected_flavor);
return 0;
}
@@ -1732,7 +1789,7 @@ static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_inf
* whether the server supports it, and then just try to use it if so.
*/
if (args->auth_info.flavor_len > 0) {
- status = nfs_verify_authflavor(args, authlist, authlist_len);
+ status = nfs_verify_authflavors(args, authlist, authlist_len);
dfprintk(MOUNT, "NFS: using auth flavor %u\n",
args->selected_flavor);
if (status)
@@ -2102,9 +2159,6 @@ static int nfs_validate_text_mount_data(void *options,
nfs_set_port(sap, &args->nfs_server.port, port);
- if (args->auth_info.flavor_len > 1)
- goto out_bad_auth;
-
return nfs_parse_devname(dev_name,
&args->nfs_server.hostname,
max_namelen,
@@ -2124,10 +2178,6 @@ out_invalid_transport_udp:
out_no_address:
dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
return -EINVAL;
-
-out_bad_auth:
- dfprintk(MOUNT, "NFS: Too many RPC auth flavours specified\n");
- return -EINVAL;
}
static int