/*
- * Copyright (C) 2005-2009 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2005-2010 Andre Noll <maan@systemlinux.org>
*
* Licensed under the GPL v2. For licencing details see COPYING.
*/
#include "crypt.h"
#include "net.h"
#include "string.h"
+#include "list.h"
#include "fd.h"
/**
return "UNKNOWN PROTOCOL";
}
+/**
+ * Flowopts: Transport-layer independent encapsulation of socket options.
+ *
+ * These collect individual socket options into a queue, which is disposed of
+ * directly after makesock(). The 'pre_conn_opt' structure is for internal use
+ * only and should not be visible elsewhere.
+ *
+ * \sa setsockopt(2), makesock()
+ */
+struct pre_conn_opt {
+ int sock_level; /**< Second argument to setsockopt() */
+ int sock_option; /**< Third argument to setsockopt() */
+ char *opt_name; /**< Stringified \a sock_option */
+ void *opt_val; /**< Fourth argument to setsockopt() */
+ socklen_t opt_len; /**< Fifth argument to setsockopt() */
+
+ struct list_head node; /**< FIFO, as sockopt order matters. */
+};
+
+/** FIFO list of pre-connection socket options to be set */
+struct flowopts {
+ struct list_head sockopts;
+};
+
+struct flowopts *flowopt_new(void)
+{
+ struct flowopts *new = para_malloc(sizeof(*new));
+
+ INIT_LIST_HEAD(&new->sockopts);
+ return new;
+}
+
+/**
+ * Append new socket option to flowopt queue.
+ *
+ * \param fo The flowopt queue to append to.
+ * \param lev Level at which \a opt resides.
+ * \param opt New option to add.
+ * \param name Stringified name of \a opt.
+ * \param val The value to set \a opt to.
+ * \param len Length of \a val.
+ *
+ * \sa setsockopt(2)
+ */
+void flowopt_add(struct flowopts *fo, int lev, int opt,
+ char *name, const void *val, int len)
+{
+ struct pre_conn_opt *new = para_malloc(sizeof(*new));
+
+ new->sock_option = opt;
+ new->sock_level = lev;
+ new->opt_name = para_strdup(name);
+
+ if (val == NULL) {
+ new->opt_val = NULL;
+ new->opt_len = 0;
+ } else {
+ new->opt_val = para_malloc(len);
+ new->opt_len = len;
+ memcpy(new->opt_val, val, len);
+ }
+
+ list_add_tail(&new->node, &fo->sockopts);
+}
+
+void flowopt_add_bool(struct flowopts *fo, int lev, int opt,
+ char *optname, bool on_or_off)
+{
+ int on = on_or_off; /* kernel takes 'int' */
+
+ flowopt_add(fo, lev, opt, optname, &on, sizeof(on));
+}
+
+/** Set the entire bunch of pre-connection options at once. */
+static void flowopt_setopts(int sockfd, struct flowopts *fo)
+{
+ struct pre_conn_opt *pc;
+
+ if (fo == NULL)
+ return;
+
+ list_for_each_entry(pc, &fo->sockopts, node)
+ if (setsockopt(sockfd, pc->sock_level, pc->sock_option,
+ pc->opt_val, pc->opt_len) < 0) {
+ PARA_EMERG_LOG("Can not set %s socket option: %s",
+ pc->opt_name, strerror(errno));
+ exit(EXIT_FAILURE);
+ }
+}
+
+static void flowopt_cleanup(struct flowopts *fo)
+{
+ struct pre_conn_opt *cur, *next;
+
+ if (fo == NULL)
+ return;
+
+ list_for_each_entry_safe(cur, next, &fo->sockopts, node) {
+ free(cur->opt_name);
+ free(cur->opt_val);
+ free(cur);
+ }
+ free(fo);
+}
+
/**
* Resolve IPv4/IPv6 address and create a ready-to-use active or passive socket.
*
- * \param l3type The layer-3 type (\p AF_INET, \p AF_INET6, \p AF_UNSPEC).
* \param l4type The layer-4 type (\p IPPROTO_xxx).
* \param passive Whether this is a passive (1) or active (0) socket.
* \param host Remote or local hostname or IPv/6 address string.
* \param port_number Decimal port number.
+ * \param fo Socket options to be set before making the connection.
*
* This creates a ready-made IPv4/v6 socket structure after looking up the
* necessary parameters. The interpretation of \a host depends on the value of
*
* Furthermore, bind(2) is called on passive sockets, and connect(2) on active
* sockets. The algorithm tries all possible address combinations until it
- * succeeds.
+ * succeeds. If \a fo is supplied, options are set and cleanup is performed.
*
* \return This function returns 1 on success and \a -E_ADDRESS_LOOKUP when no
* matching connection could be set up (with details in the error log).
*
* \sa ipv6(7), getaddrinfo(3), bind(2), connect(2).
*/
-int makesock(unsigned l3type, unsigned l4type, int passive,
- const char *host, unsigned short port_number)
+int makesock(unsigned l4type, bool passive,
+ const char *host, uint16_t port_number,
+ struct flowopts *fo)
{
struct addrinfo *local = NULL, *src,
*remote = NULL, *dst, hints;
+ unsigned int l3type = AF_UNSPEC;
int rc, on = 1, sockfd = -1,
socktype = sock_type(l4type);
char port[6]; /* port number has at most 5 digits */
goto get_next_dst;
/*
- * Set those options that need to be set before establishing
- * the connection. Reuse the address on passive (listening)
- * sockets to avoid failure on restart.
+ * Reuse the address on passive sockets to avoid failure on
+ * restart (protocols using listen()) and when creating
+ * multiple listener instances (UDP multicast).
*/
if (passive && setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR,
- &on, sizeof(on)) == -1) {
+ &on, sizeof(on)) == -1) {
+ rc = errno;
+ close(sockfd);
PARA_ERROR_LOG("can not set SO_REUSEADDR: %s\n",
- strerror(errno));
- return -ERRNO_TO_PARA_ERROR(errno);
+ strerror(rc));
+ return -ERRNO_TO_PARA_ERROR(rc);
}
+ flowopt_setopts(sockfd, fo);
if (src) {
if (bind(sockfd, src->ai_addr, src->ai_addrlen) < 0) {
freeaddrinfo(local);
if (remote)
freeaddrinfo(remote);
+ flowopt_cleanup(fo);
if (src == NULL && dst == NULL) {
+ rc = errno;
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(errno);
+ return -ERRNO_TO_PARA_ERROR(rc);
}
return sockfd;
}
/**
* Create a passive / listening socket.
*
- * \param l3type The network-layer type (\p AF_xxx).
* \param l4type The transport-layer type (\p IPPROTO_xxx).
* \param port The decimal port number to listen on.
+ * \param fo Flowopts (if any) to set before starting to listen.
*
* \return Positive integer (socket descriptor) on success, negative value
* otherwise.
*
* \sa makesock(), ip(7), ipv6(7), bind(2), listen(2).
*/
-int para_listen(unsigned l3type, unsigned l4type, unsigned short port)
+int para_listen(unsigned l4type, uint16_t port, struct flowopts *fo)
{
- int ret, fd = makesock(l3type, l4type, 1, NULL, port);
+ int ret, fd = makesock(l4type, 1, NULL, port, fo);
if (fd > 0) {
ret = listen(fd, BACKLOG);
if (ret < 0) {
+ ret = errno;
close(fd);
- return -ERRNO_TO_PARA_ERROR(errno);
+ return -ERRNO_TO_PARA_ERROR(ret);
}
PARA_INFO_LOG("listening on %s port %u, fd %d\n",
layer4_name(l4type), port, fd);
return new_fd < 0? -ERRNO_TO_PARA_ERROR(errno) : new_fd;
}
+/**
+ * Probe the list of DCCP CCIDs configured on this host.
+ * \param ccid_array Pointer to return statically allocated array in.
+ * \return Number of elements returned in \a ccid_array or error.
+ *
+ * NB: This feature is only available on Linux > 2.6.30; on older kernels
+ * ENOPROTOOPT ("Protocol not available") will be returned.
+ */
+int dccp_available_ccids(uint8_t **ccid_array)
+{
+ static uint8_t ccids[DCCP_MAX_HOST_CCIDS];
+ socklen_t nccids = sizeof(ccids);
+ int ret, fd;
+
+ ret = fd = makesock(IPPROTO_DCCP, 1, NULL, 0, NULL);
+ if (ret < 0)
+ return ret;
+
+ if (getsockopt(fd, SOL_DCCP, DCCP_SOCKOPT_AVAILABLE_CCIDS,
+ ccids, &nccids) < 0) {
+ ret = errno;
+ close(fd);
+ PARA_ERROR_LOG("No DCCP_SOCKOPT_AVAILABLE_CCIDS: %s\n",
+ strerror(ret));
+ return -ERRNO_TO_PARA_ERROR(ret);
+ }
+
+ close(fd);
+ *ccid_array = ccids;
+ return nccids;
+}
+
/**
* Prepare a structure for \p AF_UNIX socket addresses.
*