From bc995801a09d1fead0bec1356bfd836911c8eed7 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 4 Dec 2008 14:20:08 -0500 Subject: NLM: Support IPv6 scope IDs in nlm_display_address() Scope ID support is needed since the kernel's NSM implementation is about to use these displayed addresses as a mon_name in some cases. When nsm_use_hostnames is zero, without scope ID support NSM will fail to handle peers that contact us via a link-local address. Link-local addresses do not work without an interface ID, which is stored in the sockaddr's sin6_scope_id field. Signed-off-by: Chuck Lever Signed-off-by: J. Bruce Fields --- fs/lockd/host.c | 21 +++++++++++++++------ include/linux/lockd/lockd.h | 10 +++++++++- 2 files changed, 24 insertions(+), 7 deletions(-) diff --git a/fs/lockd/host.c b/fs/lockd/host.c index beb5da8..012e49a 100644 --- a/fs/lockd/host.c +++ b/fs/lockd/host.c @@ -105,22 +105,31 @@ static void nlm_clear_port(struct sockaddr *sap) } } +static void nlm_display_ipv6_address(const struct sockaddr *sap, char *buf, + const size_t len) +{ + const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap; + + if (ipv6_addr_v4mapped(&sin6->sin6_addr)) + snprintf(buf, len, "%pI4", &sin6->sin6_addr.s6_addr32[3]); + else if (sin6->sin6_scope_id != 0) + snprintf(buf, len, "%pI6%%%u", &sin6->sin6_addr, + sin6->sin6_scope_id); + else + snprintf(buf, len, "%pI6", &sin6->sin6_addr); +} + static void nlm_display_address(const struct sockaddr *sap, char *buf, const size_t len) { const struct sockaddr_in *sin = (struct sockaddr_in *)sap; - const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap; switch (sap->sa_family) { case AF_INET: snprintf(buf, len, "%pI4", &sin->sin_addr.s_addr); break; case AF_INET6: - if (ipv6_addr_v4mapped(&sin6->sin6_addr)) - snprintf(buf, len, "%pI4", - &sin6->sin6_addr.s6_addr32[3]); - else - snprintf(buf, len, "%pI6", &sin6->sin6_addr); + nlm_display_ipv6_address(sap, buf, len); break; default: snprintf(buf, len, "unsupported address family"); diff --git a/include/linux/lockd/lockd.h b/include/linux/lockd/lockd.h index dae22cb..80a0a2c 100644 --- a/include/linux/lockd/lockd.h +++ b/include/linux/lockd/lockd.h @@ -68,6 +68,14 @@ struct nlm_host { char *h_addrbuf; /* address eyecatcher */ }; +/* + * The largest string sm_addrbuf should hold is a full-size IPv6 address + * (no "::" anywhere) with a scope ID. The buffer size is computed to + * hold eight groups of colon-separated four-hex-digit numbers, a + * percent sign, a scope id (at most 32 bits, in decimal), and NUL. + */ +#define NSM_ADDRBUF ((8 * 4 + 7) + (1 + 10) + 1) + struct nsm_handle { struct list_head sm_link; atomic_t sm_count; @@ -76,7 +84,7 @@ struct nsm_handle { size_t sm_addrlen; unsigned int sm_monitored : 1, sm_sticky : 1; /* don't unmonitor */ - char sm_addrbuf[48]; /* address eyecatcher */ + char sm_addrbuf[NSM_ADDRBUF]; }; /* -- cgit v1.1