Re: [PATCH 1/2] Teach clients to map numeric strings into valid uids and gids.

[Trond Myklebust <trond.myklebust@fys.uio.no>]

On Tue, 2010-08-17 at 15:38 -0400, Steve Dickson wrote:
> When a server can not map a uid or gid they can send
> an numeric string (one that does not include the @domain)
> of the given id. When this occurs the client will can use
> that numeric representation iff that id exists on the client.
> 
> Signed-off-by: Steve Dickson <steved@redhat.com>
> ---
>  utils/idmapd/idmapd.c |   38 ++++++++++++++++++++++++++++++++++++++
>  1 files changed, 38 insertions(+), 0 deletions(-)
> 
> diff --git a/utils/idmapd/idmapd.c b/utils/idmapd/idmapd.c
> index 9ecab66..d6799c9 100644
> --- a/utils/idmapd/idmapd.c
> +++ b/utils/idmapd/idmapd.c
> @@ -826,6 +826,21 @@ idtonameres(struct idmap_msg *im)
>  		im->im_status = IDMAP_STATUS_SUCCESS;
>  }
>  
> +static int
> +alldigits(char *name)
> +{
> +	char *p = name;
> +
> +	if (name == NULL)
> +		return 0;
> +
> +	while (*p != '\0') {
> +		if (!isdigit(*p++))
> +			return 0;
> +	}
> +	return 1;
> +}
> +
>  static void
>  nametoidres(struct idmap_msg *im)
>  {
> @@ -843,6 +858,18 @@ nametoidres(struct idmap_msg *im)
>  		ret = nfs4_name_to_uid(im->im_name, &uid);
>  		im->im_id = (u_int32_t) uid;
>  		if (ret) {
> +			/*
> +			 * When a server sends numeric string that's
> +			 * lacking the @domain part, and the uid exists
> +			 * use the numeric string as the uid. 
> +			 */
> +			if (alldigits(im->im_name)) {
> +				sscanf(im->im_name, "%u", &uid);
> +				if (getpwuid(uid) != NULL) {
> +					im->im_id = uid;	
> +					break;
> +				}
> +			}
>  			im->im_status = IDMAP_STATUS_LOOKUPFAIL;
>  			im->im_id = nobodyuid;
>  		}
> @@ -851,6 +878,17 @@ nametoidres(struct idmap_msg *im)
>  		ret = nfs4_name_to_gid(im->im_name, &gid);
>  		im->im_id = (u_int32_t) gid;
>  		if (ret) {
> +			/*
> +			 * Do the same type of mapping of a numeric string
> +			 * sent as the gid.
> +			 */
> +			if (alldigits(im->im_name)) {
> +				sscanf(im->im_name, "%u", &gid);
> +				if (getgrgid(gid) != NULL) {
> +					im->im_id = gid;
> +					break;
> +				}
> +			}
>  			im->im_status = IDMAP_STATUS_LOOKUPFAIL;
>  			im->im_id = nobodygid;
>  		}

Wouldn't it make more sense to put this into libnfsidmap instead?

Cheers
  Trond