laforge has submitted this change. ( https://gerrit.osmocom.org/c/libosmocore/+/37874?usp=email )
Change subject: core/socket.c: Fix socket binding on IPv4-only hosts ......................................................................
core/socket.c: Fix socket binding on IPv4-only hosts
Let's avoid attempting to use IPv6 addresses on hosts that do not have IPv6 capability.
Change-Id: I5690a25af98089e3a8a092cb91dfc969720abdc0 Closes: SYS#7047 --- M src/core/socket.c 1 file changed, 24 insertions(+), 1 deletion(-)
Approvals: Jenkins Builder: Verified Hoernchen: Looks good to me, approved pespin: Looks good to me, but someone else must approve
diff --git a/src/core/socket.c b/src/core/socket.c index e394cf9..da20981 100644 --- a/src/core/socket.c +++ b/src/core/socket.c @@ -278,6 +278,24 @@ return 0; }
+/*! Determine if the system supports AF_INET6 sockets at all. + * We call socket(AF_INET6) once and cache the result value. */ +static bool system_supports_inet6(void) +{ + static int cached_val = -1; + + if (cached_val < 0) { + int rc = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP); + if (rc < 0 && errno == EAFNOSUPPORT) { + cached_val = 0; + } else { + cached_val = 1; + close(rc); + } + } + return cached_val == 1; +} + /*! Initialize a socket (including bind and/or connect) * \param[in] family Address Family like AF_INET, AF_INET6, AF_UNSPEC * \param[in] type Socket type like SOCK_DGRAM, SOCK_STREAM @@ -343,7 +361,12 @@ /* It must do a full run to ensure AF_UNSPEC does not fail. * In case first local valid entry is IPv4 and only remote valid entry * is IPv6 or vice versa */ - if (family == AF_UNSPEC) { + if (!system_supports_inet6()) { + /* if no AF_INET6 is supported, then the decision is easy...*/ + local_ipv4 = true; + remote_ipv4 = true; + family = AF_INET; + } else if (family == AF_UNSPEC) { for (rp = local; rp != NULL; rp = rp->ai_next) { switch (rp->ai_family) { case AF_INET:
-
laforge