/*
- * Copyright (C) 2005-2009 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2005-2013 Andre Noll <maan@systemlinux.org>
*
* Licensed under the GPL v2. For licencing details see COPYING.
*/
#define AI_ADDRCONFIG 0
#endif
-#include <dirent.h>
#include <regex.h>
-#include <openssl/rc4.h>
#include "para.h"
#include "error.h"
-#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;
+};
+
+/**
+ * Allocate and initialize a flowopt queue.
+ *
+ * \return A new structure to be passed to \ref flowopt_add(). It is
+ * automatically deallocated in \ref makesock().
+ */
+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,
+ const 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);
+}
+
+/** 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;
+ 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);
char port[6]; /* port number has at most 5 digits */
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 */
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));
+ rc = -ERRNO_TO_PARA_ERROR(rc);
+ break;
}
+ flowopt_setopts(sockfd, fo);
if (src) {
if (bind(sockfd, src->ai_addr, src->ai_addrlen) < 0) {
if (src && (src = src->ai_next)) /* restart inner loop */
dst = remote;
}
+out:
if (local)
freeaddrinfo(local);
if (remote)
freeaddrinfo(remote);
+ flowopt_cleanup(fo);
if (src == NULL && dst == NULL) {
+ 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(errno);
+ return 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);
: 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;
}
/**
- * Print numeric host and port number (beware - uses static char).
+ * 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;
+}
+
+/**
+ * Get the maximum transport-layer message size (MMS_S).
+ *
+ * \param sockfd The socket file descriptor.
*
- * \param sa The IPv4/IPv6 socket address to use.
+ * The socket must be connected. See RFC 1122, 3.3.3. If the protocol familiy
+ * could not be determined, \p AF_INET is assumed.
*
- * \sa getnameinfo(3), services(5), nsswitch.conf(5)
+ * \return The maximum message size of the address family type.
*/
-static char *host_and_port(const struct sockaddr_storage *ss)
+int generic_max_transport_msg_size(int sockfd)
{
- const struct sockaddr *sa = normalize_ip_address(ss);
- char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
- static char output[sizeof(hbuf) + sizeof(sbuf) + 2];
- int ret;
+ struct sockaddr_storage ss;
+ socklen_t sslen = sizeof(ss);
+ int af_type = AF_INET;
- 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 {
- snprintf(output, sizeof(output), "(unknown)");
- PARA_WARNING_LOG("hostname lookup error (%s).\n",
- gai_strerror(ret));
+ 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 output;
+ return generic_mtu(af_type) - estimated_header_overhead(af_type);
}
/**
* remote side.
*
* \return A static character string identifying hostname and port of the
- * chosen side.
+ * chosen side in numeric host:port format.
*
- * \sa getsockname(2), getpeername(2).
+ * \sa getsockname(2), getpeername(2), parse_url(), getnameinfo(3),
+ * services(5), nsswitch.conf(5).
*/
-static char *__get_sock_name(int fd, int (*getname)(int, struct sockaddr*,
- socklen_t *))
+static char *__get_sock_name(int fd, typeof(getsockname) getname)
{
struct sockaddr_storage ss;
+ const struct sockaddr *sa;
socklen_t sslen = sizeof(ss);
+ char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
+ static char output[sizeof(hbuf) + sizeof(sbuf) + 4];
+ int ret;
if (getname(fd, (struct sockaddr *)&ss, &sslen) < 0) {
- static char *dont_know = "(don't know)";
PARA_ERROR_LOG("can not determine address from fd %d: %s\n",
fd, strerror(errno));
- return dont_know;
+ snprintf(output, sizeof(output), "(unknown)");
+ return output;
}
- return host_and_port(&ss);
+ sa = normalize_ip_address(&ss);
+ ret = getnameinfo(sa, salen(sa), hbuf, sizeof(hbuf), sbuf,
+ sizeof(sbuf), NI_NUMERICHOST | NI_NUMERICSERV);
+ if (ret) {
+ PARA_WARNING_LOG("hostname lookup error (%s).\n",
+ gai_strerror(ret));
+ snprintf(output, sizeof(output), "(lookup error)");
+ } 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;
}
/**
/**
* Extract IPv4 or IPv6-mapped-IPv4 address from sockaddr_storage.
- * \param ss Container of IPv4/6 address
- * \return Extracted IPv4 address (different from 0) or 0 if unsuccessful.
*
- * \sa RFC 3493
+ * \param ss Container of IPv4/6 address.
+ * \param ia Extracted IPv4 address (different from 0) or 0 if unsuccessful.
+ *
+ * \sa RFC 3493.
*/
-struct in_addr extract_v4_addr(const struct sockaddr_storage *ss)
+void extract_v4_addr(const struct sockaddr_storage *ss, struct in_addr *ia)
{
- struct in_addr ia = {.s_addr = 0};
const struct sockaddr *sa = normalize_ip_address(ss);
+ memset(ia, 0, sizeof(*ia));
if (sa->sa_family == AF_INET)
- ia = ((struct sockaddr_in *)sa)->sin_addr;
- return ia;
-}
-
-/**
- * Send a binary buffer.
- *
- * \param fd The file descriptor.
- * \param buf The buffer to be sent.
- * \param len The length of \a buf.
- *
- * Send out the buffer and try to resend the remaining part in case of short
- * writes.
- *
- * \return Standard.
- */
-int send_bin_buffer(int fd, const char *buf, size_t len)
-{
- if (!len)
- PARA_CRIT_LOG("len == 0\n");
- return write_all(fd, buf, &len);
-}
-
-/**
- * Send a \p NULL-terminated buffer.
- *
- * \param fd The file descriptor.
- * \param buf The null-terminated buffer to be send.
- *
- * This is equivalent to send_bin_buffer(fd, buf, strlen(buf)).
- *
- * \return Standard.
- */
-int send_buffer(int fd, const char *buf)
-{
- return send_bin_buffer(fd, buf, strlen(buf));
-}
-
-/**
- * Send a buffer given by a format string.
- *
- * \param fd The file descriptor.
- * \param fmt A format string.
- *
- * \return Standard.
- */
-__printf_2_3 int send_va_buffer(int fd, const char *fmt, ...)
-{
- char *msg;
- int ret;
-
- PARA_VSPRINTF(fmt, msg);
- ret = send_buffer(fd, msg);
- free(msg);
- return ret;
+ *ia = ((struct sockaddr_in *)sa)->sin_addr;
}
/**
* Wrapper around the accept system call.
*
* \param fd The listening socket.
+ * \param rfds An optional fd_set pointer.
* \param addr Structure which is filled in with the address of the peer socket.
* \param size Should contain the size of the structure pointed to by \a addr.
+ * \param new_fd Result pointer.
*
- * Accept incoming connections on \a addr. Retry if interrupted.
+ * Accept incoming connections on \a addr, retry if interrupted. If \a rfds is
+ * not \p NULL, return 0 if \a fd is not set in \a rfds without calling accept().
*
- * \return The new file descriptor on success, negative on errors.
+ * \return Negative on errors, zero if no connections are present to be accepted,
+ * one otherwise.
*
* \sa accept(2).
*/
-int para_accept(int fd, void *addr, socklen_t size)
+int para_accept(int fd, fd_set *rfds, void *addr, socklen_t size, int *new_fd)
{
- int new_fd;
+ int ret;
+ if (rfds && !FD_ISSET(fd, rfds))
+ return 0;
do
- new_fd = accept(fd, (struct sockaddr *) addr, &size);
- while (new_fd < 0 && errno == EINTR);
- return new_fd < 0? -ERRNO_TO_PARA_ERROR(errno) : new_fd;
+ ret = accept(fd, (struct sockaddr *) addr, &size);
+ while (ret < 0 && errno == EINTR);
+
+ if (ret >= 0) {
+ *new_fd = ret;
+ return 1;
+ }
+ if (errno == EAGAIN || errno == EWOULDBLOCK)
+ return 0;
+ return -ERRNO_TO_PARA_ERROR(errno);
+}
+
+/**
+ * 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;
}
/**
* 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;
#ifndef HAVE_UCRED
ssize_t send_cred_buffer(int sock, char *buf)
{
- return send_buffer(sock, buf);
+ return write_buffer(sock, buf);
}
int recv_cred_buffer(int fd, char *buf, size_t size)
{
return result;
}
#endif /* HAVE_UCRED */
-
-/**
- * Receive a buffer and check for a pattern.
- *
- * \param fd The file descriptor to receive from.
- * \param pattern The expected pattern.
- * \param bufsize The size of the internal buffer.
- *
- * \return Positive if \a pattern was received, negative otherwise.
- *
- * This function tries to receive at most \a bufsize bytes from file descriptor
- * \a fd. If at least \p strlen(\a pattern) bytes were received, the beginning
- * of the received buffer is compared with \a pattern, ignoring case.
- *
- * \sa recv_buffer(), \sa strncasecmp(3).
- */
-int recv_pattern(int fd, const char *pattern, size_t bufsize)
-{
- size_t len = strlen(pattern);
- char *buf = para_malloc(bufsize + 1);
- int ret = -E_RECV_PATTERN, n = recv_buffer(fd, buf, bufsize + 1);
-
- if (n < len)
- goto out;
- if (strncasecmp(buf, pattern, len))
- goto out;
- ret = 1;
-out:
- if (ret < 0) {
- PARA_NOTICE_LOG("did not receive pattern '%s'\n", pattern);
- if (n > 0)
- PARA_NOTICE_LOG("recvd %d bytes: %s\n", n, buf);
- else if (n < 0)
- PARA_NOTICE_LOG("%s\n", para_strerror(-n));
- }
- free(buf);
- return ret;
-}
projects / paraslash.git / blobdiff