From a26cfad6e0a308a2c68df1f1ef50aabd48b17e6d Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Mon, 18 Aug 2008 19:34:16 -0400 Subject: [PATCH] SUNRPC: Support IPv6 when registering kernel RPC services In order to advertise NFS-related services on IPv6 interfaces via rpcbind, the kernel RPC server implementation must use rpcb_v4_register() instead of rpcb_register(). A new kernel build option allows distributions to use the legacy v2 call until they integrate an appropriate user-space rpcbind daemon that can support IPv6 RPC services. I tried adding some automatic logic to fall back if registering with a v4 protocol request failed, but there are too many corner cases. So I just made it a compile-time switch that distributions can throw when they've replaced portmapper with rpcbind. Signed-off-by: Chuck Lever Signed-off-by: J. Bruce Fields --- fs/Kconfig | 22 +++++++++ include/linux/sunrpc/svc.h | 4 +- net/sunrpc/svc.c | 95 +++++++++++++++++++++++++++++++++++--- 3 files changed, 113 insertions(+), 8 deletions(-) diff --git a/fs/Kconfig b/fs/Kconfig index c6ae4d4842eb..ed57a5a37250 100644 --- a/fs/Kconfig +++ b/fs/Kconfig @@ -1773,6 +1773,28 @@ config SUNRPC_XPRT_RDMA If unsure, say N. +config SUNRPC_REGISTER_V4 + bool "Register local RPC services via rpcbind v4 (EXPERIMENTAL)" + depends on SUNRPC && EXPERIMENTAL + default n + help + Sun added support for registering RPC services at an IPv6 + address by creating two new versions of the rpcbind protocol + (RFC 1833). + + This option enables support in the kernel RPC server for + registering kernel RPC services via version 4 of the rpcbind + protocol. If you enable this option, you must run a portmapper + daemon that supports rpcbind protocol version 4. + + Serving NFS over IPv6 from knfsd (the kernel's NFS server) + requires that you enable this option and use a portmapper that + supports rpcbind version 4. + + If unsure, say N to get traditional behavior (register kernel + RPC services using only rpcbind version 2). Distributions + using the legacy Linux portmapper daemon must say N here. + config RPCSEC_GSS_KRB5 tristate "Secure RPC: Kerberos V mechanism (EXPERIMENTAL)" depends on SUNRPC && EXPERIMENTAL diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h index 23143f38b121..54a79e1ad634 100644 --- a/include/linux/sunrpc/svc.h +++ b/include/linux/sunrpc/svc.h @@ -393,7 +393,9 @@ struct svc_serv * svc_create_pooled(struct svc_program *, unsigned int, int svc_set_num_threads(struct svc_serv *, struct svc_pool *, int); void svc_destroy(struct svc_serv *); int svc_process(struct svc_rqst *); -int svc_register(struct svc_serv *, int, unsigned short); +int svc_register(const struct svc_serv *, const unsigned short, + const unsigned short); + void svc_wake_up(struct svc_serv *); void svc_reserve(struct svc_rqst *rqstp, int space); struct svc_pool * svc_pool_for_cpu(struct svc_serv *serv, int cpu); diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c index 9eb78a771da5..c43ccb628052 100644 --- a/net/sunrpc/svc.c +++ b/net/sunrpc/svc.c @@ -719,13 +719,92 @@ svc_exit_thread(struct svc_rqst *rqstp) } EXPORT_SYMBOL(svc_exit_thread); +#ifdef CONFIG_SUNRPC_REGISTER_V4 /* - * Register an RPC service with the local portmapper. - * To unregister a service, call this routine with - * proto and port == 0. + * Registering kernel RPC services with rpcbind version 2 will work + * over either IPv4 or IPv6, since the Linux kernel always registers + * services for the "any" address. + * + * However, the local rpcbind daemon listens on either only AF_INET + * or AF_INET6 (never both). When it listens on AF_INET6, an rpcbind + * version 2 registration will result in registering the service at + * IN6ADDR_ANY, even if the RPC service being registered is not + * IPv6-enabled. + * + * Rpcbind version 4 allows us to be a little more specific. Kernel + * RPC services that don't yet support AF_INET6 can register + * themselves as IPv4-only with the local rpcbind daemon, even if the + * daemon is listening only on AF_INET6. + * + * And, registering IPv6-enabled kernel RPC services via AF_INET6 + * verifies that the local user space rpcbind daemon is properly + * configured to support remote AF_INET6 rpcbind requests. + * + * An AF_INET6 registration request will fail if the local rpcbind + * daemon is not set up to listen on AF_INET6. Likewise, we fail + * AF_INET6 registration requests if svc_register() is configured to + * support only rpcbind version 2. */ -int -svc_register(struct svc_serv *serv, int proto, unsigned short port) +static int __svc_register(const u32 program, const u32 version, + const sa_family_t family, + const unsigned short protocol, + const unsigned short port) +{ + struct sockaddr_in sin = { + .sin_family = AF_INET, + .sin_addr.s_addr = htonl(INADDR_ANY), + .sin_port = htons(port), + }; + struct sockaddr_in6 sin6 = { + .sin6_family = AF_INET6, + .sin6_addr = IN6ADDR_ANY_INIT, + .sin6_port = htons(port), + }; + struct sockaddr *sap; + char *netid; + + switch (family) { + case AF_INET: + sap = (struct sockaddr *)&sin; + netid = RPCBIND_NETID_TCP; + if (protocol == IPPROTO_UDP) + netid = RPCBIND_NETID_UDP; + break; + case AF_INET6: + sap = (struct sockaddr *)&sin6; + netid = RPCBIND_NETID_TCP6; + if (protocol == IPPROTO_UDP) + netid = RPCBIND_NETID_UDP6; + break; + default: + return -EAFNOSUPPORT; + } + + return rpcb_v4_register(program, version, sap, netid); +} +#else +static int __svc_register(const u32 program, const u32 version, + sa_family_t family, + const unsigned short protocol, + const unsigned short port) +{ + if (family != AF_INET) + return -EAFNOSUPPORT; + + return rpcb_register(program, version, protocol, port); +} +#endif + +/** + * svc_register - register an RPC service with the local portmapper + * @serv: svc_serv struct for the service to register + * @proto: transport protocol number to advertise + * @port: port to advertise + * + * Service is registered for any address in serv's address family + */ +int svc_register(const struct svc_serv *serv, const unsigned short proto, + const unsigned short port) { struct svc_program *progp; unsigned int i; @@ -738,8 +817,9 @@ svc_register(struct svc_serv *serv, int proto, unsigned short port) if (progp->pg_vers[i] == NULL) continue; - dprintk("svc: svc_register(%s, %s, %d, %d)%s\n", + dprintk("svc: svc_register(%s, %u, %s, %u, %d)%s\n", progp->pg_name, + serv->sv_family, proto == IPPROTO_UDP? "udp" : "tcp", port, i, @@ -749,7 +829,8 @@ svc_register(struct svc_serv *serv, int proto, unsigned short port) if (progp->pg_vers[i]->vs_hidden) continue; - error = rpcb_register(progp->pg_prog, i, proto, port); + error = __svc_register(progp->pg_prog, i, + serv->sv_family, proto, port); if (error < 0) break; }