socket: Introduce API osmo_sock_multiaddr_get_ip_and_port()
This API will be used internally by osmo_sock_multiaddr_get_name_buf()
in a follow-up patch.
This API can also be used directly by user who wish to obtain a list of
local/remote IP addresses and port from an SCTP socket.
Related: SYS#6636
Related: OS#5581
Change-Id: I19d560ab4aadec18a4c0f94115675ec1d7ab14d7
diff --git a/src/core/libosmocore.map b/src/core/libosmocore.map
index 30c4927..ffbbd2f 100644
--- a/src/core/libosmocore.map
+++ b/src/core/libosmocore.map
@@ -436,6 +436,7 @@
osmo_sock_mcast_ttl_set;
osmo_sock_multiaddr_add_local_addr;
osmo_sock_multiaddr_del_local_addr;
+osmo_sock_multiaddr_get_ip_and_port;
osmo_sock_set_dscp;
osmo_sock_set_priority;
osmo_sock_unix_init;
diff --git a/src/core/socket.c b/src/core/socket.c
index 7fc1b72..51703ef 100644
--- a/src/core/socket.c
+++ b/src/core/socket.c
@@ -1868,6 +1868,95 @@
return 0;
}
+/*! Get multiple IP addresses and/or port number on socket in separate string buffers
+ * \param[in] fd file descriptor of socket.
+ * \param[out] ip_proto IPPROTO of the socket, eg: IPPROTO_SCTP.
+ * \param[out] ip Pointer to memory holding consecutive buffers of size ip_len.
+ * \param[out] ip_cnt length ip array pointer. on return it contains the number of addresses found.
+ * \param[in] ip_len length of each of the string buffer in the the ip array.
+ * \param[out] port number (will be filled in when not NULL).
+ * \param[in] port_len length of the port buffer.
+ * \param[in] local (true) or remote (false) name will get looked at.
+ * \returns 0 on success; negative otherwise.
+ *
+ * Upon return, ip_cnt can be set to a higher value than the one set by the
+ * caller. This can be used by the caller to find out the required array length
+ * and then obtaining by calling the function twice. Only up to ip_cnt addresses
+ * are filed in, as per the value provided by the caller.
+ *
+ * Usage example retrieving all (up to OSMO_SOCK_MAX_ADDRS, 32) bound IP addresses and bound port:
+ * char hostbuf[OSMO_SOCK_MAX_ADDRS][INET6_ADDRSTRLEN];
+ * size_t num_hostbuf = ARRAY_SIZE(hostbuf);
+ * char portbuf[6];
+ * rc = osmo_sock_multiaddr_get_ip_and_port(fd, IPPROTO_SCTP, &hostbuf[0][0], &num_hostbuf,
+ * sizeof(hostbuf[0]), portbuf, sizeof(portbuf), true);
+ * if (rc < 0)
+ * goto error;
+ * if (num_hostbuf > ARRAY_SIZE(hostbuf))
+ * goto not_enough_buffers;
+ */
+int osmo_sock_multiaddr_get_ip_and_port(int fd, int ip_proto, char *ip, size_t *ip_cnt, size_t ip_len,
+ char *port, size_t port_len, bool local)
+{
+ struct sockaddr *addrs = NULL;
+ unsigned int n_addrs, i;
+ void *addr_buf;
+ int rc;
+
+ switch (ip_proto) {
+ case IPPROTO_SCTP:
+ break; /* continue below */
+ default:
+ if (*ip_cnt == 0) {
+ *ip_cnt = 1;
+ return 0;
+ }
+ *ip_cnt = 1;
+ return osmo_sock_get_ip_and_port(fd, ip, ip_len, port, port_len, local);
+ }
+
+ rc = local ? sctp_getladdrs(fd, 0, &addrs) : sctp_getpaddrs(fd, 0, &addrs);
+ if (rc < 0)
+ return rc;
+ if (rc == 0)
+ return -ENOTCONN;
+
+ n_addrs = rc;
+ addr_buf = (void *)addrs;
+ for (i = 0; i < n_addrs; i++) {
+ struct sockaddr *sa_addr = (struct sockaddr *)addr_buf;
+ size_t addrlen;
+
+ if (i >= *ip_cnt)
+ break;
+
+ switch (sa_addr->sa_family) {
+ case AF_INET:
+ addrlen = sizeof(struct sockaddr_in);
+ break;
+ case AF_INET6:
+ addrlen = sizeof(struct sockaddr_in6);
+ break;
+ default:
+ rc = -EINVAL;
+ goto free_addrs_ret;
+ }
+
+ rc = getnameinfo(sa_addr, addrlen, &ip[i * ip_len], ip_len,
+ port, port_len,
+ NI_NUMERICHOST | NI_NUMERICSERV);
+ if (rc < 0)
+ goto free_addrs_ret;
+ addr_buf += addrlen;
+ }
+
+ *ip_cnt = n_addrs;
+ rc = 0;
+free_addrs_ret:
+ local ? sctp_freeladdrs(addrs) : sctp_freepaddrs(addrs);
+ return rc;
+}
+
/*! Get local IP address on socket
* \param[in] fd file descriptor of socket
* \param[out] ip IP address (will be filled in)