nfsd: add IPv6 addr escaping to fs_location hosts

The fs_location->hosts list is split on colons, but this doesn't work when
IPv6 addresses are used (they contain colons).
This patch adds the function nfsd4_encode_components_esc() to
allow the caller to specify escape characters when splitting on 'sep'.
In order to fix referrals, this patch must be used with the mountd patch
that similarly fixes IPv6 [] escaping.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 61555e7..30817e9 100644 (file)
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -1744,15 +1744,16 @@ static void encode_seqid_op_tail(struct nfsd4_compoundres *resp, __be32 *save, _
 }
 
 /* Encode as an array of strings the string given with components
- * separated @sep.
+ * separated @sep, escaped with esc_enter and esc_exit.
  */
-static __be32 nfsd4_encode_components(char sep, char *components,
-                                  __be32 **pp, int *buflen)
+static __be32 nfsd4_encode_components_esc(char sep, char *components,
+                                  __be32 **pp, int *buflen,
+                                  char esc_enter, char esc_exit)
 {
        __be32 *p = *pp;
        __be32 *countp = p;
        int strlen, count=0;
-       char *str, *end;
+       char *str, *end, *next;
 
        dprintk("nfsd4_encode_components(%s)\n", components);
        if ((*buflen -= 4) < 0)
@@ -1760,8 +1761,23 @@ static __be32 nfsd4_encode_components(char sep, char *components,
        WRITE32(0); /* We will fill this in with @count later */
        end = str = components;
        while (*end) {
-               for (; *end && (*end != sep); end++)
-                       ; /* Point to end of component */
+               bool found_esc = false;
+
+               /* try to parse as esc_start, ..., esc_end, sep */
+               if (*str == esc_enter) {
+                       for (; *end && (*end != esc_exit); end++)
+                               /* find esc_exit or end of string */;
+                       next = end + 1;
+                       if (*end && (!*next || *next == sep)) {
+                               str++;
+                               found_esc = true;
+                       }
+               }
+
+               if (!found_esc)
+                       for (; *end && (*end != sep); end++)
+                               /* find sep or end of string */;
+
                strlen = end - str;
                if (strlen) {
                        if ((*buflen -= ((XDR_QUADLEN(strlen) << 2) + 4)) < 0)
@@ -1780,6 +1796,15 @@ static __be32 nfsd4_encode_components(char sep, char *components,
        return 0;
 }
 
+/* Encode as an array of strings the string given with components
+ * separated @sep.
+ */
+static __be32 nfsd4_encode_components(char sep, char *components,
+                                  __be32 **pp, int *buflen)
+{
+       return nfsd4_encode_components_esc(sep, components, pp, buflen, 0, 0);
+}
+
 /*
  * encode a location element of a fs_locations structure
  */
@@ -1789,7 +1814,8 @@ static __be32 nfsd4_encode_fs_location4(struct nfsd4_fs_location *location,
        __be32 status;
        __be32 *p = *pp;
 
-       status = nfsd4_encode_components(':', location->hosts, &p, buflen);
+       status = nfsd4_encode_components_esc(':', location->hosts, &p, buflen,
+                                               '[', ']');
        if (status)
                return status;
        status = nfsd4_encode_components('/', location->path, &p, buflen);