pespin has uploaded this change for review. (
https://gerrit.osmocom.org/c/libosmocore/+/15781 )
Change subject: socket: Introduce API osmo_sock_init2_multiaddr()
......................................................................
socket: Introduce API osmo_sock_init2_multiaddr()
This API will be used by libosmo-netif's osmo_stream for SCTP sockets,
which in turn will be used by libosmo-sccp to support multi-homed
connections.
Related: OS#3608
Change-Id: Ic8681d9e093216c99c6bca4be81c31ef83688ed1
---
M configure.ac
M include/osmocom/core/socket.h
M src/Makefile.am
M src/socket.c
4 files changed, 306 insertions(+), 2 deletions(-)
git pull ssh://gerrit.osmocom.org:29418/libosmocore refs/changes/81/15781/1
diff --git a/configure.ac b/configure.ac
index 39d232b..2aefd2c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -100,6 +100,17 @@
AC_CHECK_FUNCS(clock_gettime localtime_r)
+old_LIBS=$LIBS
+AC_SEARCH_LIBS([sctp_bindx], [sctp], [
+ AC_DEFINE(HAVE_LIBSCTP, 1, [Define 1 to enable SCTP support])
+ AC_SUBST(HAVE_LIBSCTP, [1])
+ if test -n "$ac_lib"; then
+ AC_SUBST(LIBSCTP_LIBS, [-l$ac_lib])
+ fi
+ ], [
+ AC_MSG_ERROR([sctp_bindx not found in searched libs])])
+LIBS=$old_LIBS
+
AC_DEFUN([CHECK_TM_INCLUDES_TM_GMTOFF], [
AC_CACHE_CHECK(
[whether struct tm has tm_gmtoff member],
diff --git a/include/osmocom/core/socket.h b/include/osmocom/core/socket.h
index 37b1eae..e26ca0d 100644
--- a/include/osmocom/core/socket.h
+++ b/include/osmocom/core/socket.h
@@ -36,6 +36,9 @@
/*! use SO_REUSEADDR on UDP ports (required for multicast) */
#define OSMO_SOCK_F_UDP_REUSEADDR (1 << 5)
+/*! maximum number of local or remote addresses supported by an osmo_sock
instance */
+#define OSMO_SOCK_MAX_ADDRS 32
+
int osmo_sock_init(uint16_t family, uint16_t type, uint8_t proto,
const char *host, uint16_t port, unsigned int flags);
@@ -43,6 +46,10 @@
const char *local_host, uint16_t local_port,
const char *remote_host, uint16_t remote_port, unsigned int
flags);
+int osmo_sock_init2_multiaddr(uint16_t family, uint16_t type, uint8_t proto,
+ const char **local_hosts, size_t local_hosts_cnt, uint16_t
local_port,
+ const char **remote_hosts, size_t remote_hosts_cnt, uint16_t
remote_port, unsigned int flags);
+
int osmo_sock_init_ofd(struct osmo_fd *ofd, int family, int type, int proto,
const char *host, uint16_t port, unsigned int flags);
diff --git a/src/Makefile.am b/src/Makefile.am
index 5f5f017..9943281 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -4,7 +4,7 @@
LIBVERSION=14:0:2
AM_CPPFLAGS = -I$(top_srcdir)/include -I$(top_builddir)/include
-AM_CFLAGS = -Wall $(TALLOC_CFLAGS) $(PTHREAD_CFLAGS)
+AM_CFLAGS = -Wall $(TALLOC_CFLAGS) $(PTHREAD_CFLAGS) $(LIBSCTP_CFLAGS)
if ENABLE_PSEUDOTALLOC
AM_CPPFLAGS += -I$(top_srcdir)/src/pseudotalloc
@@ -12,7 +12,7 @@
lib_LTLIBRARIES = libosmocore.la
-libosmocore_la_LIBADD = $(BACKTRACE_LIB) $(TALLOC_LIBS) $(LIBRARY_RT)
$(PTHREAD_LIBS)
+libosmocore_la_LIBADD = $(BACKTRACE_LIB) $(TALLOC_LIBS) $(LIBRARY_RT)
$(PTHREAD_LIBS) $(LIBSCTP_LIBS)
libosmocore_la_SOURCES = context.c timer.c timer_gettimeofday.c
timer_clockgettime.c \
select.c signal.c msgb.c bits.c \
bitvec.c bitcomp.c counter.c fsm.c \
diff --git a/src/socket.c b/src/socket.c
index ef3bb58..542c76e 100644
--- a/src/socket.c
+++ b/src/socket.c
@@ -53,6 +53,10 @@
#include <netdb.h>
#include <ifaddrs.h>
+#ifdef HAVE_LIBSCTP
+#include <netinet/sctp.h>
+#endif
+
static struct addrinfo *addrinfo_helper(uint16_t family, uint16_t type,
uint8_t proto,
const char *host, uint16_t port, bool
passive)
{
@@ -96,6 +100,34 @@
return result;
}
+/*! Retrieve an array of addrinfo with specified hints, one for each host in
the hosts array.
+ * \param[out] addrinfo array of addrinfo pointers, will be filled by the
function on success.
+ * Its size must be at least the one of hosts.
+ * \param[in] family Socket family like AF_INET, AF_INET6.
+ * \param[in] type Socket type like SOCK_DGRAM, SOCK_STREAM.
+ * \param[in] proto Protocol like IPPROTO_TCP, IPPROTO_UDP.
+ * \param[in] hosts array of char pointers (strings) containing the addresses
to query.
+ * \param[in] host_cnt length of the hosts array (in items).
+ * \param[in] port port number in host byte order.
+ * \param[in] passive whether to include the AI_PASSIVE flag in getaddrinfo()
hints.
+ * \returns 0 is returned on success together with a filled addrinfo array;
negative on error
+ */
+static int addrinfo_helper_multi(struct addrinfo **addrinfo, uint16_t family,
uint16_t type, uint8_t proto,
+ const char **hosts, size_t host_cnt,
uint16_t port, bool passive)
+{
+ int i, j;
+
+ for (i = 0; i < host_cnt; i++) {
+ addrinfo[i] = addrinfo_helper(family, type, proto, hosts[i],
port, passive);
+ if (!addrinfo[i]) {
+ for (j = 0; j < i; j++)
+ freeaddrinfo(addrinfo[j]);
+ return -EINVAL;
+ }
+ }
+ return 0;
+}
+
static int socket_helper(const struct addrinfo *rp, unsigned int flags)
{
int sfd, on = 1;
@@ -118,6 +150,37 @@
return sfd;
}
+/* Fill buf with a string representation of the address set, in the form:
+ * buf_len == 0: "()"
+ * buf_len == 1: "hostA"
+ * buf_len >= 2: (hostA|hostB|...|...)
+ */
+static int multiaddr_snprintf(char* buf, size_t buf_len, const char **hosts,
size_t host_cnt)
+{
+ int len = 0, offset = 0, rem = buf_len;
+ int ret, i;
+ char *after;
+
+ if (buf_len < 3)
+ return -EINVAL;
+
+ if (host_cnt != 1) {
+ ret = snprintf(buf, rem, "(");
+ if (ret < 0)
+ return ret;
+ OSMO_SNPRINTF_RET(ret, rem, offset, len);
+ }
+ for (i = 0; i < host_cnt; i++) {
+ if (host_cnt == 1)
+ after = "";
+ else
+ after = (i == (host_cnt - 1)) ? ")" : "|";
+ ret = snprintf(buf + offset, rem, "%s%s", hosts[i] ? :
"0.0.0.0", after);
+ OSMO_SNPRINTF_RET(ret, rem, offset, len);
+ }
+
+ return len;
+}
static int osmo_sock_init_tail(int fd, uint16_t type, unsigned int flags)
{
@@ -294,6 +357,229 @@
return sfd;
}
+#ifdef HAVE_LIBSCTP
+
+
+/* Build array of addresses taking first addrinfo result of the requested
family
+ * for each host in hosts. addrs4 or addrs6 are filled based on family type. */
+static int addrinfo_to_sockaddr(uint16_t family, const struct addrinfo
**result,
+ const char **hosts, int host_cont,
+ struct sockaddr_in *addrs4, struct sockaddr_in6
*addrs6) {
+ size_t host_idx;
+ const struct addrinfo *rp;
+ OSMO_ASSERT(family == AF_INET || family == AF_INET6);
+
+ for (host_idx = 0; host_idx < host_cont; host_idx++) {
+ for (rp = result[host_idx]; rp != NULL; rp = rp->ai_next) {
+ if (rp->ai_family != family)
+ continue;
+ if (family == AF_INET)
+ memcpy(&addrs4[host_idx], rp->ai_addr,
sizeof(addrs4[host_idx]));
+ else
+ memcpy(&addrs6[host_idx], rp->ai_addr,
sizeof(addrs6[host_idx]));
+ break;
+ }
+ if (!rp) { /* No addr could be bound for this host! */
+ LOGP(DLGLOBAL, LOGL_ERROR, "No suitable remote address
found for host: %s\n",
+ hosts[host_idx]);
+ return -ENODEV;
+ }
+ }
+ return 0;
+}
+
+/*! Initialize a socket (including bind and/or connect) with multiple local or
remote addresses.
+ * \param[in] family Address Family like AF_INET, AF_INET6, AF_UNSPEC
+ * \param[in] type Socket type like SOCK_DGRAM, SOCK_STREAM
+ * \param[in] proto Protocol like IPPROTO_TCP, IPPROTO_UDP
+ * \param[in] local_hosts array of char pointers (strings), each containing
local host name or IP address in string form
+ * \param[in] local_hosts_cnt length of local_hosts (in items)
+ * \param[in] local_port local port number in host byte order
+ * \param[in] remote_host array of char pointers (strings), each containing
remote host name or IP address in string form
+ * \param[in] remote_hosts_cnt length of remote_hosts (in items)
+ * \param[in] remote_port remote port number in host byte order
+ * \param[in] flags flags like \ref OSMO_SOCK_F_CONNECT
+ * \returns socket file descriptor on success; negative on error
+ *
+ * This function is similar to \ref osmo_sock_init2(), but can be passed an
+ * array of local or remote addresses for protocols supporting multiple
+ * addresses per socket, like SCTP (currently only one supported). This
function
+ * should not be used by protocols not supporting this kind of features, but
+ * rather \ref osmo_sock_init2() should be used instead.
+ * See \ref osmo_sock_init2() for more information on flags and general
behavior.
+ */
+int osmo_sock_init2_multiaddr(uint16_t family, uint16_t type, uint8_t proto,
+ const char **local_hosts, size_t local_hosts_cnt, uint16_t
local_port,
+ const char **remote_hosts, size_t remote_hosts_cnt, uint16_t
remote_port,
+ unsigned int flags)
+
+{
+ struct addrinfo *result[OSMO_SOCK_MAX_ADDRS];
+ int sfd = -1, rc, on = 1;
+ int i;
+ struct sockaddr_in addrs4[OSMO_SOCK_MAX_ADDRS];
+ struct sockaddr_in6 addrs6[OSMO_SOCK_MAX_ADDRS];
+ struct sockaddr *addrs;
+ char strbuf[512];
+
+ /* TODO: So far this function is only aimed for SCTP, but could be
+ reused in the future for other protocols with multi-addr support */
+ if (proto != IPPROTO_SCTP)
+ return -ENOTSUP;
+
+ /* TODO: Let's not support AF_UNSPEC for now. sctp_bindx() actually
+ supports binding both types of addresses on a AF_INET6 soscket, but
+ that would mean we could get both AF_INET and AF_INET6 addresses for
+ each host, and makes complexity of this function increase a lot since
+ we'd need to find out which subsets to use, use v4v6 mapped socket,
+ etc. */
+ if (family == AF_UNSPEC)
+ return -ENOTSUP;
+
+ if ((flags & (OSMO_SOCK_F_BIND | OSMO_SOCK_F_CONNECT)) == 0) {
+ LOGP(DLGLOBAL, LOGL_ERROR, "invalid: you have to specify either
"
+ "BIND or CONNECT flags\n");
+ return -EINVAL;
+ }
+
+ if (((flags & OSMO_SOCK_F_BIND) && !local_hosts_cnt) ||
+ ((flags & OSMO_SOCK_F_CONNECT) && !remote_hosts_cnt) ||
+ local_hosts_cnt > OSMO_SOCK_MAX_ADDRS ||
+ remote_hosts_cnt > OSMO_SOCK_MAX_ADDRS)
+ return -EINVAL;
+
+ /* figure out local side of socket */
+ if (flags & OSMO_SOCK_F_BIND) {
+ rc = addrinfo_helper_multi(result, family, type, proto,
local_hosts,
+ local_hosts_cnt, local_port,
true);
+ if (rc < 0)
+ return -EINVAL;
+
+ /* Since addrinfo_helper sets ai_family, socktype and
+ ai_protocol in hints, we know all results will use same
+ values, so simply pick the first one and pass it to create
+ the socket:
+ */
+ sfd = socket_helper(result[0], flags);
+ if (sfd < 0) {
+ for (i = 0; i < local_hosts_cnt; i++)
+ freeaddrinfo(result[i]);
+ return sfd;
+ }
+
+ if (proto != IPPROTO_UDP || flags & OSMO_SOCK_F_UDP_REUSEADDR) {
+ rc = setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR,
+ &on, sizeof(on));
+ if (rc < 0) {
+ multiaddr_snprintf(strbuf, sizeof(strbuf),
local_hosts, local_hosts_cnt);
+ LOGP(DLGLOBAL, LOGL_ERROR,
+ "cannot setsockopt socket:"
+ " %s:%u: %s\n",
+ strbuf, local_port,
+ strerror(errno));
+ for (i = 0; i < local_hosts_cnt; i++)
+ freeaddrinfo(result[i]);
+ close(sfd);
+ return rc;
+ }
+ }
+
+ /* Build array of addresses taking first of same family for
each host.
+ TODO: Ideally we should use backtracking storing last used
+ indexes and trying next combination if connect() fails .*/
+ rc = addrinfo_to_sockaddr(family, (const struct addrinfo
**)result,
+ local_hosts, local_hosts_cnt, addrs4,
addrs6);
+ if (rc < 0) {
+ for (i = 0; i < local_hosts_cnt; i++)
+ freeaddrinfo(result[i]);
+ close(sfd);
+ return -ENODEV;
+ }
+
+ if (family == AF_INET)
+ addrs = (struct sockaddr *)addrs4;
+ else
+ addrs = (struct sockaddr *)addrs6;
+ if (sctp_bindx(sfd, addrs, local_hosts_cnt,
SCTP_BINDX_ADD_ADDR) == -1) {
+ multiaddr_snprintf(strbuf, sizeof(strbuf), local_hosts,
local_hosts_cnt);
+ LOGP(DLGLOBAL, LOGL_NOTICE, "unable to bind socket:
%s:%u: %s\n",
+ strbuf, local_port, strerror(errno));
+ for (i = 0; i < local_hosts_cnt; i++)
+ freeaddrinfo(result[i]);
+ close(sfd);
+ return -ENODEV;
+ }
+ for (i = 0; i < local_hosts_cnt; i++)
+ freeaddrinfo(result[i]);
+ }
+
+ /* Reached this point, if OSMO_SOCK_F_BIND then sfd is valid (>=0) or it
+ was already closed and func returned. If OSMO_SOCK_F_BIND is not
+ set, then sfd = -1 */
+
+ /* figure out remote side of socket */
+ if (flags & OSMO_SOCK_F_CONNECT) {
+ rc = addrinfo_helper_multi(result, family, type, proto,
remote_hosts,
+ remote_hosts_cnt, remote_port,
false);
+ if (rc < 0) {
+ if (sfd >= 0)
+ close(sfd);
+ return -EINVAL;
+ }
+
+ if (sfd < 0) {
+ /* Since addrinfo_helper sets ai_family, socktype and
+ ai_protocol in hints, we know all results will use
same
+ values, so simply pick the first one and pass it to
create
+ the socket:
+ */
+ sfd = socket_helper(result[0], flags);
+ if (sfd < 0) {
+ for (i = 0; i < remote_hosts_cnt; i++)
+ freeaddrinfo(result[i]);
+ return sfd;
+ }
+ }
+
+ /* Build array of addresses taking first of same family for
each host.
+ TODO: Ideally we should use backtracking storing last used
+ indexes and trying next combination if connect() fails .*/
+ rc = addrinfo_to_sockaddr(family, (const struct addrinfo
**)result,
+ remote_hosts, remote_hosts_cnt,
addrs4, addrs6);
+ if (rc < 0) {
+ for (i = 0; i < remote_hosts_cnt; i++)
+ freeaddrinfo(result[i]);
+ close(sfd);
+ return -ENODEV;
+ }
+
+ if (family == AF_INET)
+ addrs = (struct sockaddr *)addrs4;
+ else
+ addrs = (struct sockaddr *)addrs6;
+ rc = sctp_connectx(sfd, addrs, remote_hosts_cnt, NULL);
+ if (rc != 0 && errno != EINPROGRESS) {
+ multiaddr_snprintf(strbuf, sizeof(strbuf),
remote_hosts, remote_hosts_cnt);
+ LOGP(DLGLOBAL, LOGL_ERROR, "unable to connect socket:
%s:%u: %s\n",
+ strbuf, remote_port, strerror(errno));
+ for (i = 0; i < remote_hosts_cnt; i++)
+ freeaddrinfo(result[i]);
+ close(sfd);
+ return -ENODEV;
+ }
+ for (i = 0; i < remote_hosts_cnt; i++)
+ freeaddrinfo(result[i]);
+ }
+
+ rc = osmo_sock_init_tail(sfd, type, flags);
+ if (rc < 0) {
+ close(sfd);
+ sfd = -1;
+ }
+
+ return sfd;
+}
+#endif /* HAVE_LIBSCTP */
/*! Initialize a socket (including bind/connect)
* \param[in] family Address Family like AF_INET, AF_INET6, AF_UNSPEC
--
To view, visit https://gerrit.osmocom.org/c/libosmocore/+/15781
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Gerrit-Project: libosmocore
Gerrit-Branch: master
Gerrit-Change-Id: Ic8681d9e093216c99c6bca4be81c31ef83688ed1
Gerrit-Change-Number: 15781
Gerrit-PatchSet: 1
Gerrit-Owner: pespin <pes...@sysmocom.de>
Gerrit-MessageType: newchange
