/*
- * Copyright (C) 2005-2010 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2005-2011 Andre Noll <maan@systemlinux.org>
*
* Licensed under the GPL v2. For licencing details see COPYING.
*/
const char *host, uint16_t port_number,
struct flowopts *fo)
{
- struct addrinfo *local = NULL, *src,
- *remote = NULL, *dst, hints;
+ struct addrinfo *local = NULL, *src = NULL, *remote = NULL,
+ *dst = NULL, hints;
unsigned int l3type = AF_UNSPEC;
int rc, on = 1, sockfd = -1,
socktype = sock_type(l4type);
layer4_name(l4type),
host? host : (passive? "[loopback]" : "[localhost]"),
port, gai_strerror(rc));
- return -E_ADDRESS_LOOKUP;
+ rc = -E_ADDRESS_LOOKUP;
+ goto out;
}
/* Iterate over all src/dst combination, exhausting dst first */
close(sockfd);
PARA_ERROR_LOG("can not set SO_REUSEADDR: %s\n",
strerror(rc));
- return -ERRNO_TO_PARA_ERROR(rc);
+ rc = -ERRNO_TO_PARA_ERROR(rc);
+ break;
}
flowopt_setopts(sockfd, fo);
if (src && (src = src->ai_next)) /* restart inner loop */
dst = remote;
}
+out:
if (local)
freeaddrinfo(local);
if (remote)
flowopt_cleanup(fo);
if (src == NULL && dst == NULL) {
- rc = errno;
+ if (rc >= 0)
+ rc = -E_MAKESOCK;
PARA_ERROR_LOG("can not create %s socket %s#%s.\n",
layer4_name(l4type), host? host : (passive?
"[loopback]" : "[localhost]"), port);
- return -ERRNO_TO_PARA_ERROR(rc);
+ return rc;
}
return sockfd;
}
: sizeof(struct sockaddr_in);
}
+/** True if @ss holds a v6-mapped-v4 address (RFC 4291, 2.5.5.2) */
+static bool SS_IS_ADDR_V4MAPPED(const struct sockaddr_storage *ss)
+{
+ const struct sockaddr_in6 *ia6 = (const struct sockaddr_in6 *)ss;
+
+ return ss->ss_family == AF_INET6 && IN6_IS_ADDR_V4MAPPED(&ia6->sin6_addr);
+}
+
/**
* Process IPv4/v6 address, turn v6-mapped-v4 address into normal IPv4 address.
* \param ss Container of IPv4/6 address.
static const struct sockaddr *
normalize_ip_address(const struct sockaddr_storage *ss)
{
- const struct sockaddr_in6 *ia6 = (const struct sockaddr_in6 *)ss;
-
assert(ss->ss_family == AF_INET || ss->ss_family == AF_INET6);
- if (ss->ss_family == AF_INET6 && IN6_IS_ADDR_V4MAPPED(&ia6->sin6_addr)) {
+ if (SS_IS_ADDR_V4MAPPED(ss)) {
+ const struct sockaddr_in6 *ia6 = (const struct sockaddr_in6 *)ss;
static struct sockaddr_in ia;
ia.sin_family = AF_INET;
return (const struct sockaddr *)ss;
}
+/**
+ * Generic/fallback MTU values
+ *
+ * These are taken from RFC 1122, RFC 2460, and RFC 5405.
+ * - RFC 1122, 3.3.3 defines EMTU_S ("Effective MTU for sending") and recommends
+ * to use an EMTU_S size of of 576 bytes if the IPv4 path MTU is unknown;
+ * - RFC 2460, 5. requires a minimum IPv6 MTU of 1280 bytes;
+ * - RFC 5405, 3.2 recommends that if path MTU discovery is not done,
+ * UDP senders should use the respective minimum values of EMTU_S.
+ */
+static inline int generic_mtu(const int af_type)
+{
+ return af_type == AF_INET6 ? 1280 : 576;
+}
+
+/** Crude approximation of IP header overhead - neglecting options. */
+static inline int estimated_header_overhead(const int af_type)
+{
+ return af_type == AF_INET6 ? 40 : 20;
+}
+
+/**
+ * Maximum transport-layer message size (MMS_S) as per RFC 1122, 3.3.3
+ * Socket must be connected.
+ */
+int generic_max_transport_msg_size(int sockfd)
+{
+ struct sockaddr_storage ss;
+ socklen_t sslen = sizeof(ss);
+ int af_type = AF_INET;
+
+ if (getpeername(sockfd, (struct sockaddr *)&ss, &sslen) < 0) {
+ PARA_ERROR_LOG("can not determine remote address type: %s\n",
+ strerror(errno));
+ } else if (!SS_IS_ADDR_V4MAPPED(&ss)) {
+ af_type = ss.ss_family;
+ }
+ return generic_mtu(af_type) - estimated_header_overhead(af_type);
+}
+
/**
* Print numeric host and port number (beware - uses static char).
*
* \param sa The IPv4/IPv6 socket address to use.
*
+ * \return Host string in numeric host:port format, \sa parse_url().
* \sa getnameinfo(3), services(5), nsswitch.conf(5)
*/
static char *host_and_port(const struct sockaddr_storage *ss)
{
const struct sockaddr *sa = normalize_ip_address(ss);
char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
- static char output[sizeof(hbuf) + sizeof(sbuf) + 2];
+ static char output[sizeof(hbuf) + sizeof(sbuf) + 4];
int ret;
ret = getnameinfo(sa, salen(sa),
hbuf, sizeof(hbuf),
sbuf, sizeof(sbuf),
- NI_NUMERICHOST);
- if (ret == 0) {
- snprintf(output, sizeof(output), "%s#%s", hbuf, sbuf);
- } else {
+ NI_NUMERICHOST | NI_NUMERICSERV);
+ if (ret) {
snprintf(output, sizeof(output), "(unknown)");
PARA_WARNING_LOG("hostname lookup error (%s).\n",
gai_strerror(ret));
+ } else if (sa->sa_family == AF_INET6) {
+ snprintf(output, sizeof(output), "[%s]:%s", hbuf, sbuf);
+ } else {
+ snprintf(output, sizeof(output), "%s:%s", hbuf, sbuf);
}
return output;
}
* This function creates a local socket for sequenced, reliable, two-way,
* connection-based byte streams.
*
- * \return The file descriptor, on success, negative on errors.
+ * \return The file descriptor of the connected socket on success, negative on
+ * errors.
*
* \sa create_local_socket(), unix(7), connect(2).
*/
-int create_remote_socket(const char *name)
+int connect_local_socket(const char *name)
{
struct sockaddr_un unix_addr;
int fd, ret;
+ PARA_DEBUG_LOG("connecting to %s\n", name);
ret = init_unix_addr(&unix_addr, name);
if (ret < 0)
return ret;
projects / paraslash.git / blobdiff