Re: [PATCH v2] rpc.nfsd: Squelch DNS errors when using the --host option

[Kinglong Mee <kinglongmee@gmail.com>]

On 6/10/2015 9:04 AM, Chuck Lever wrote:
> Sean Elble <elbles@sessys.com> says:
>> [rpc.nfsd --host] throws an error/warning (where nfs-server is
>> defined in /etc/hosts for the IPv4 address of the interface I wish
>> for TCP port 2049 to be opened on):
>>
>>  rpc.nfsd: unable to resolve nfs-server:nfs to inet6 address: Name
>>  or service not known
> 
> I think we can simplify the use of getaddrinfo(3) so that only one
> call is needed to gather both IPv4 and IPv6 addresses. The call
> should fail, and an error should be reported, only when there are
> _no_ addresses bound to a hostname.
> 
> Reported-by: Sean Elble <elbles@sessys.com>
> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
> ---
> 
> Second take, after review by Jeff. This one should now create both
> an IPv4 and an IPv6 listener in the case where -H is not specified.
> 
> 
>  utils/nfsd/nfsd.c   |   75 +++------------------------------------------------
>  utils/nfsd/nfssvc.c |    9 +++++-
>  utils/nfsd/nfssvc.h |    2 +
>  3 files changed, 13 insertions(+), 73 deletions(-)
> 
> diff --git a/utils/nfsd/nfsd.c b/utils/nfsd/nfsd.c
> index 201bb13..586a9f2 100644
> --- a/utils/nfsd/nfsd.c
> +++ b/utils/nfsd/nfsd.c
> @@ -52,50 +52,6 @@ static struct option longopts[] =
>  	{ NULL, 0, 0, 0 }
>  };
>  
> -/* given a family and ctlbits, disable any that aren't listed in netconfig */
> -#ifdef HAVE_LIBTIRPC
> -static void
> -nfsd_enable_protos(unsigned int *proto4, unsigned int *proto6)
> -{
> -	struct netconfig *nconf;
> -	unsigned int *famproto;
> -	void *handle;
> -
> -	xlog(D_GENERAL, "Checking netconfig for visible protocols.");
> -
> -	handle = setnetconfig();
> -	while((nconf = getnetconfig(handle))) {
> -		if (!(nconf->nc_flag & NC_VISIBLE))
> -			continue;
> -
> -		if (!strcmp(nconf->nc_protofmly, NC_INET))
> -			famproto = proto4;
> -		else if (!strcmp(nconf->nc_protofmly, NC_INET6))
> -			famproto = proto6;
> -		else
> -			continue;
> -
> -		if (!strcmp(nconf->nc_proto, NC_TCP))
> -			NFSCTL_TCPSET(*famproto);
> -		else if (!strcmp(nconf->nc_proto, NC_UDP))
> -			NFSCTL_UDPSET(*famproto);
> -
> -		xlog(D_GENERAL, "Enabling %s %s.", nconf->nc_protofmly,
> -			nconf->nc_proto);
> -	}
> -	endnetconfig(handle);
> -	return;
> -}
> -#else /* HAVE_LIBTIRPC */
> -static void
> -nfsd_enable_protos(unsigned int *proto4, unsigned int *proto6)
> -{
> -	/* Enable all IPv4 protocols if no TIRPC support */
> -	*proto4 = NFSCTL_ALLBITS;
> -	*proto6 = 0;
> -}
> -#endif /* HAVE_LIBTIRPC */
> -
>  int
>  main(int argc, char **argv)
>  {
> @@ -108,8 +64,6 @@ main(int argc, char **argv)
>  	unsigned int minorversset = 0;
>  	unsigned int versbits = NFSCTL_VERDEFAULT;
>  	unsigned int protobits = NFSCTL_ALLBITS;
> -	unsigned int proto4 = 0;
> -	unsigned int proto6 = 0;
>  	int grace = -1;
>  	int lease = -1;
>  
> @@ -278,18 +232,6 @@ main(int argc, char **argv)
>  
>  	xlog_open(progname);
>  
> -	nfsd_enable_protos(&proto4, &proto6);
> -
> -	if (!NFSCTL_TCPISSET(protobits)) {
> -		NFSCTL_TCPUNSET(proto4);
> -		NFSCTL_TCPUNSET(proto6);
> -	}
> -
> -	if (!NFSCTL_UDPISSET(protobits)) {
> -		NFSCTL_UDPUNSET(proto4);
> -		NFSCTL_UDPUNSET(proto6);
> -	}
> -
>  	/* make sure that at least one version is enabled */
>  	found_one = 0;
>  	for (c = NFSD_MINVERS; c <= NFSD_MAXVERS; c++) {
> @@ -302,8 +244,7 @@ main(int argc, char **argv)
>  	}
>  
>  	if (NFSCTL_VERISSET(versbits, 4) &&
> -	    !NFSCTL_TCPISSET(proto4) &&
> -	    !NFSCTL_TCPISSET(proto6)) {
> +	    !NFSCTL_TCPISSET(protobits)) {
>  		xlog(L_ERROR, "version 4 requires the TCP protocol");
>  		exit(1);
>  	}
> @@ -335,23 +276,17 @@ main(int argc, char **argv)
>  	if (lease  > 0)
>  		nfssvc_set_time("lease", lease);
>  
> -	i = 0;
> -	do {
> -		error = nfssvc_set_sockets(AF_INET, proto4, haddr[i], port);
> +	for (i = 0; i < hcounter; i++) {
> +		error = nfssvc_set_sockets(protobits, haddr[i], port);

Must use do {} while() here,
otherwise nfssvc_set_sockets will never be called when rpc.nfsd without anything.

>  		if (!error)
>  			socket_up = 1;
> -#ifdef IPV6_SUPPORTED
> -		error = nfssvc_set_sockets(AF_INET6, proto6, haddr[i], port);
> -		if (!error)
> -			socket_up = 1;
> -#endif /* IPV6_SUPPORTED */
> -	} while (++i < hcounter); 
> -
> +	}
>  	if (rdma_port) {
>  		error = nfssvc_set_rdmaport(rdma_port);
>  		if (!error)
>  			socket_up = 1;
>  	}
> +
>  set_threads:
>  	/* don't start any threads if unable to hand off any sockets */
>  	if (!socket_up) {
> diff --git a/utils/nfsd/nfssvc.c b/utils/nfsd/nfssvc.c
> index 027e5ac..2bcd600 100644
> --- a/utils/nfsd/nfssvc.c
> +++ b/utils/nfsd/nfssvc.c
> @@ -24,6 +24,7 @@
>  
>  #include "nfslib.h"
>  #include "xlog.h"
> +#include "nfssvc.h"
>  
>  #ifndef NFSD_FS_DIR
>  #define NFSD_FS_DIR	  "/proc/fs/nfsd"
> @@ -252,12 +253,16 @@ error:
>  }
> 

Also, nfssvc_setfds needs update, otherwise, 

rpc.nfsd: Unknown address family specified: 0

rpc.nfsd: unable to set any sockets for nfsd

@@ -125,6 +126,9 @@ nfssvc_setfds(const struct addrinfo *hints, const char *node, const char *port)
                return 0;

        switch(hints->ai_family) {
+       case AF_UNSPEC:
+               family = "unspec";
+               break;
        case AF_INET:
                family = "inet";
                break;
@@ -252,12 +256,16 @@ error:

thanks,
Kinglong Mee

>  int
> -nfssvc_set_sockets(const int family, const unsigned int protobits,
> +nfssvc_set_sockets(const unsigned int protobits,
>  		   const char *host, const char *port)
>  {
>  	struct addrinfo hints = { .ai_flags = AI_PASSIVE };
>  
> -	hints.ai_family = family;
> +#ifdef IPV6_SUPPORTED
> +	hints.ai_family = AF_UNSPEC;
> +#else
> +	hints.ai_family = AF_INET;
> +#endif
>  
>  	if (!NFSCTL_ANYPROTO(protobits))
>  		return EPROTOTYPE;
> diff --git a/utils/nfsd/nfssvc.h b/utils/nfsd/nfssvc.h
> index fbb89b2..7d70f0d 100644
> --- a/utils/nfsd/nfssvc.h
> +++ b/utils/nfsd/nfssvc.h
> @@ -22,7 +22,7 @@
>  
>  void	nfssvc_mount_nfsdfs(char *progname);
>  int	nfssvc_inuse(void);
> -int	nfssvc_set_sockets(const int family, const unsigned int protobits,
> +int	nfssvc_set_sockets(const unsigned int protobits,
>  			   const char *host, const char *port);
>  void	nfssvc_set_time(const char *type, const int seconds);
>  int	nfssvc_set_rdmaport(const char *port);
> 
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