-/*
- Copyright (C) Andrew Tridgell 1998
+/* -*- c-file-style: "linux" -*-
+
+ Copyright (C) 1992-2001 by Andrew Tridgell <tridge@samba.org>
+ Copyright (C) 2001 by Martin Pool <mbp@samba.org>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
-/*
- socket functions used in rsync
-
- */
+/**
+ * @file socket.c
+ *
+ * Socket functions used in rsync.
+ **/
#include "rsync.h"
-/* open a socket to a tcp remote host with the specified port
- based on code from Warren */
-int open_socket_out(char *host, int port)
+#ifndef HAVE_GETADDRINFO
+#include "lib/addrinfo.h"
+#endif
+
+/* Establish a proxy connection on an open socket to a web roxy by
+ * using the CONNECT method. */
+static int establish_proxy_connection(int fd, char *host, int port)
{
- int type = SOCK_STREAM;
- struct sockaddr_in sock_out;
- int res;
- struct hostent *hp;
-
+ char buffer[1024];
+ char *cp;
- res = socket(PF_INET, type, 0);
- if (res == -1) {
+ snprintf(buffer, sizeof(buffer), "CONNECT %s:%d HTTP/1.0\r\n\r\n", host, port);
+ if (write(fd, buffer, strlen(buffer)) != strlen(buffer)) {
+ rprintf(FERROR, "failed to write to proxy: %s\n",
+ strerror(errno));
return -1;
}
- hp = gethostbyname(host);
- if (!hp) {
- rprintf(FERROR,"unknown host: %s\n", host);
+ for (cp = buffer; cp < &buffer[sizeof(buffer) - 1]; cp++) {
+ if (read(fd, cp, 1) != 1) {
+ rprintf(FERROR, "failed to read from proxy: %s\n",
+ strerror(errno));
+ return -1;
+ }
+ if (*cp == '\n')
+ break;
+ }
+
+ if (*cp != '\n')
+ cp++;
+ *cp-- = '\0';
+ if (*cp == '\r')
+ *cp = '\0';
+ if (strncmp(buffer, "HTTP/", 5) != 0) {
+ rprintf(FERROR, "bad response from proxy - %s\n",
+ buffer);
+ return -1;
+ }
+ for (cp = &buffer[5]; isdigit(*cp) || (*cp == '.'); cp++)
+ ;
+ while (*cp == ' ')
+ cp++;
+ if (*cp != '2') {
+ rprintf(FERROR, "bad response from proxy - %s\n",
+ buffer);
return -1;
}
+ /* throw away the rest of the HTTP header */
+ while (1) {
+ for (cp = buffer; cp < &buffer[sizeof(buffer) - 1];
+ cp++) {
+ if (read(fd, cp, 1) != 1) {
+ rprintf(FERROR, "failed to read from proxy: %s\n",
+ strerror(errno));
+ return -1;
+ }
+ if (*cp == '\n')
+ break;
+ }
+ if ((cp > buffer) && (*cp == '\n'))
+ cp--;
+ if ((cp == buffer) && ((*cp == '\n') || (*cp == '\r')))
+ break;
+ }
+ return 0;
+}
+
- memcpy(&sock_out.sin_addr, hp->h_addr, hp->h_length);
- sock_out.sin_port = htons(port);
- sock_out.sin_family = PF_INET;
- if (connect(res,(struct sockaddr *)&sock_out,sizeof(sock_out))) {
- close(res);
- rprintf(FERROR,"failed to connect to %s - %s\n", host, strerror(errno));
+/**
+ * Open a socket to a tcp remote host with the specified port .
+ *
+ * Based on code from Warren. Proxy support by Stephen Rothwell.
+ * getaddrinfo() rewrite contributed by KAME.net.
+ *
+ * Now that we support IPv6 we need to look up the remote machine's
+ * address first, using @p af_hint to set a preference for the type
+ * of address. Then depending on whether it has v4 or v6 addresses we
+ * try to open a connection.
+ *
+ * The loop allows for machines with some addresses which may not be
+ * reachable, perhaps because we can't e.g. route ipv6 to that network
+ * but we can get ip4 packets through.
+ *
+ * @param bind_address Local address to use. Normally NULL to bind
+ * the wildcard address.
+ *
+ * @param af_hint Address family, e.g. AF_INET or AF_INET6.
+ **/
+int open_socket_out(char *host, int port, const char *bind_address,
+ int af_hint)
+{
+ int type = SOCK_STREAM;
+ int error;
+ int s;
+ int result;
+ struct addrinfo hints, *res0, *res;
+ char portbuf[10];
+ char *h;
+ int proxied = 0;
+ char buffer[1024];
+ char *cp;
+
+ /* if we have a RSYNC_PROXY env variable then redirect our
+ * connetcion via a web proxy at the given address. The format
+ * is hostname:port */
+ h = getenv("RSYNC_PROXY");
+ proxied = (h != NULL) && (*h != '\0');
+
+ if (proxied) {
+ strlcpy(buffer, h, sizeof(buffer));
+ cp = strchr(buffer, ':');
+ if (cp == NULL) {
+ rprintf(FERROR,
+ "invalid proxy specification: should be HOST:PORT\n");
+ return -1;
+ }
+ *cp++ = '\0';
+ strcpy(portbuf, cp);
+ h = buffer;
+ } else {
+ snprintf(portbuf, sizeof(portbuf), "%d", port);
+ h = host;
+ }
+
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_family = af_hint;
+ hints.ai_socktype = type;
+ error = getaddrinfo(h, portbuf, &hints, &res0);
+ if (error) {
+ rprintf(FERROR, RSYNC_NAME ": getaddrinfo: %s %s: %s\n",
+ h, portbuf, gai_strerror(error));
return -1;
}
- set_nonblocking(res);
+ s = -1;
+ for (res = res0; res; res = res->ai_next) {
+ s = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
+ if (s < 0)
+ continue;
+
+ if (bind_address) {
+ struct addrinfo bhints, *bres;
+
+ memset(&bhints, 0, sizeof(bhints));
+ bhints.ai_family = res->ai_family;
+ bhints.ai_socktype = type;
+ bhints.ai_flags = AI_PASSIVE;
+ error = getaddrinfo(bind_address, NULL, &bhints, &bres);
+ if (error) {
+ rprintf(FERROR, RSYNC_NAME ": getaddrinfo: bind address %s <noport>: %s\n",
+ bind_address, gai_strerror(error));
+ continue;
+ }
+ if (bres->ai_next) {
+ rprintf(FERROR, RSYNC_NAME ": getaddrinfo: bind address %s resolved to multiple hosts\n",
+ bind_address);
+ freeaddrinfo(bres);
+ continue;
+ }
+ bind(s, bres->ai_addr, bres->ai_addrlen);
+ }
- return res;
+ if (connect(s, res->ai_addr, res->ai_addrlen) < 0) {
+ close(s);
+ s = -1;
+ continue;
+ }
+ if (proxied &&
+ establish_proxy_connection(s, host, port) != 0) {
+ close(s);
+ s = -1;
+ continue;
+ } else
+ break;
+ }
+ freeaddrinfo(res0);
+ if (s < 0) {
+ rprintf(FERROR, RSYNC_NAME ": failed to connect to %s: %s\n",
+ h, strerror(errno));
+ return -1;
+ }
+ return s;
}
-/****************************************************************************
-open a socket of the specified type, port and address for incoming data
-****************************************************************************/
-static int open_socket_in(int type, int port)
+/**
+ * Open an outgoing socket, but allow for it to be intercepted by
+ * $RSYNC_CONNECT_PROG, which will execute a program across a TCP
+ * socketpair rather than really opening a socket.
+ *
+ * We use this primarily in testing to detect TCP flow bugs, but not
+ * cause security problems by really opening remote connections.
+ *
+ * This is based on the Samba LIBSMB_PROG feature.
+ *
+ * @param bind_address Local address to use. Normally NULL to get the stack default.
+ **/
+int open_socket_out_wrapped (char *host,
+ int port,
+ const char *bind_address,
+ int af_hint)
{
- struct hostent *hp;
- struct sockaddr_in sock;
- char host_name[200];
- int res;
- int one=1;
+ char *prog;
+
+ if ((prog = getenv ("RSYNC_CONNECT_PROG")) != NULL)
+ return sock_exec (prog);
+ else
+ return open_socket_out (host, port, bind_address,
+ af_hint);
+}
+
- /* get my host name */
- if (gethostname(host_name, sizeof(host_name)) == -1) {
- rprintf(FERROR,"gethostname failed\n");
- return -1;
- }
- /* get host info */
- if ((hp = gethostbyname(host_name)) == 0) {
- rprintf(FERROR,"gethostbyname: Unknown host %s\n",host_name);
+/**
+ * Open a socket of the specified type, port and address for incoming data
+ *
+ * Try to be better about handling the results of getaddrinfo(): when
+ * opening an inbound socket, we might get several address results,
+ * e.g. for the machine's ipv4 and ipv6 name.
+ *
+ * If binding a wildcard, then any one of them should do. If an address
+ * was specified but it's insufficiently specific then that's not our
+ * fault.
+ *
+ * However, some of the advertized addresses may not work because e.g. we
+ * don't have IPv6 support in the kernel. In that case go on and try all
+ * addresses until one succeeds.
+ *
+ * @param bind_address Local address to bind, or NULL to allow it to
+ * default.
+ **/
+static int open_socket_in(int type, int port, const char *bind_address,
+ int af_hint)
+{
+ int one=1;
+ int s;
+ struct addrinfo hints, *res, *resp;
+ char portbuf[10];
+ int error;
+
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_family = af_hint;
+ hints.ai_socktype = type;
+ hints.ai_flags = AI_PASSIVE;
+ snprintf(portbuf, sizeof(portbuf), "%d", port);
+ error = getaddrinfo(bind_address, portbuf, &hints, &res);
+ if (error) {
+ rprintf(FERROR, RSYNC_NAME ": getaddrinfo: bind address %s: %s\n",
+ bind_address, gai_strerror(error));
return -1;
}
-
- memset((char *)&sock,0,sizeof(sock));
- memcpy((char *)&sock.sin_addr,(char *)hp->h_addr, hp->h_length);
- sock.sin_port = htons(port);
- sock.sin_family = hp->h_addrtype;
- sock.sin_addr.s_addr = INADDR_ANY;
- res = socket(hp->h_addrtype, type, 0);
- if (res == -1) {
- rprintf(FERROR,"socket failed\n");
- return -1;
+ /* XXX: Do we need to care about getting multiple results
+ * back? I think probably not; if the user passed
+ * bind_address == NULL and we set AI_PASSIVE then we ought to
+ * get a wildcard result. */
+
+ resp = res;
+ while (1) {
+ s = socket(resp->ai_family, resp->ai_socktype, resp->ai_protocol);
+
+ if (s >= 0) {
+ break; /* got a socket */
+ } else if ((resp = resp->ai_next)) {
+ switch (errno) {
+ case EPROTONOSUPPORT:
+ case EAFNOSUPPORT:
+ case EPFNOSUPPORT:
+ /* See if there's another address that will work... */
+ continue;
+ }
+ }
+
+ rprintf(FERROR, RSYNC_NAME ": open inbound socket"
+ "(dom=%d, type=%d, proto=%d) failed: %s\n",
+ resp->ai_family, resp->ai_socktype, resp->ai_protocol,
+ strerror(errno));
+ goto fail;
}
- setsockopt(res,SOL_SOCKET,SO_REUSEADDR,(char *)&one,sizeof(one));
+ setsockopt(s,SOL_SOCKET,SO_REUSEADDR,(char *)&one,sizeof(one));
/* now we've got a socket - we need to bind it */
- if (bind(res, (struct sockaddr * ) &sock,sizeof(sock)) == -1) {
- rprintf(FERROR,"bind failed on port %d\n", port);
- close(res);
- return -1;
+ if (bind(s, res->ai_addr, res->ai_addrlen) < 0) {
+ rprintf(FERROR, RSYNC_NAME ": bind failed on port %d\n", port);
+ close(s);
+ goto fail;
}
- return res;
+ return s;
+
+fail:
+ freeaddrinfo(res);
+ return -1;
}
-/****************************************************************************
-determine if a file descriptor is in fact a socket
-****************************************************************************/
+/*
+ * Determine if a file descriptor is in fact a socket
+ */
int is_a_socket(int fd)
{
- int v,l;
+ int v;
+ socklen_t l;
l = sizeof(int);
+
+ /* Parameters to getsockopt, setsockopt etc are very
+ * unstandardized across platforms, so don't be surprised if
+ * there are compiler warnings on e.g. SCO OpenSwerver or AIX.
+ * It seems they all eventually get the right idea.
+ *
+ * Debian says: ``The fifth argument of getsockopt and
+ * setsockopt is in reality an int [*] (and this is what BSD
+ * 4.* and libc4 and libc5 have). Some POSIX confusion
+ * resulted in the present socklen_t. The draft standard has
+ * not been adopted yet, but glibc2 already follows it and
+ * also has socklen_t [*]. See also accept(2).''
+ *
+ * We now return to your regularly scheduled programming. */
return(getsockopt(fd, SOL_SOCKET, SO_TYPE, (char *)&v, &l) == 0);
}
void start_accept_loop(int port, int (*fn)(int ))
{
int s;
+ extern char *bind_address;
/* open an incoming socket */
- s = open_socket_in(SOCK_STREAM, port);
+ s = open_socket_in(SOCK_STREAM, port, bind_address,
+ global_opts.af_hint);
if (s == -1)
- exit_cleanup(1);
+ exit_cleanup(RERR_SOCKETIO);
/* ready to listen */
if (listen(s, 5) == -1) {
close(s);
- exit_cleanup(1);
+ exit_cleanup(RERR_SOCKETIO);
}
struct sockaddr addr;
int in_addrlen = sizeof(addr);
+ /* close log file before the potentially very long select so
+ file can be trimmed by another process instead of growing
+ forever */
+ log_close();
+
FD_ZERO(&fds);
FD_SET(s, &fds);
if(!FD_ISSET(s, &fds)) continue;
- fd = accept(s,&addr,&in_addrlen);
+ fd = accept(s,(struct sockaddr *)&addr,&in_addrlen);
if (fd == -1) continue;
but I have had reports that on Digital Unix zombies
are produced, so this ensures that they are reaped */
#ifdef WNOHANG
- waitpid(-1, NULL, WNOHANG);
+ while (waitpid(-1, NULL, WNOHANG) > 0);
#endif
if (fork()==0) {
close(s);
-
- set_nonblocking(fd);
-
+ /* open log file in child before possibly giving
+ up privileges */
+ log_open();
_exit(fn(fd));
}
}
if (ret != 0)
- rprintf(FERROR,"Failed to set socket option %s\n",tok);
+ rprintf(FERROR, "failed to set socket option %s: %s\n", tok,
+ strerror(errno));
}
free(options);
}
}
-/*******************************************************************
- return the IP addr of the client as a string
- ******************************************************************/
+/**
+ * Return the IP addr of the client as a string
+ **/
char *client_addr(int fd)
{
- struct sockaddr sa;
- struct sockaddr_in *sockin = (struct sockaddr_in *) (&sa);
- int length = sizeof(sa);
+ struct sockaddr ss;
+ int length = sizeof(ss);
static char addr_buf[100];
+ static int initialised;
- if (getpeername(fd, &sa, &length)) {
- exit_cleanup(1);
- }
+ if (initialised) return addr_buf;
+
+ initialised = 1;
- strlcpy(addr_buf,(char *)inet_ntoa(sockin->sin_addr), sizeof(addr_buf)-1);
+ if (getpeername(fd, &ss, &length)) {
+ exit_cleanup(RERR_SOCKETIO);
+ }
+ getnameinfo(&ss, length,
+ addr_buf, sizeof(addr_buf), NULL, 0, NI_NUMERICHOST);
return addr_buf;
}
-/*******************************************************************
- return the DNS name of the client
- ******************************************************************/
+/**
+ * Return the DNS name of the client
+ **/
char *client_name(int fd)
{
- struct sockaddr sa;
- struct sockaddr_in *sockin = (struct sockaddr_in *) (&sa);
- int length = sizeof(sa);
+ struct sockaddr ss;
+ int length = sizeof(ss);
static char name_buf[100];
- struct hostent *hp;
- char **p;
+ static char port_buf[100];
char *def = "UNKNOWN";
+ static int initialised;
+ struct addrinfo hints, *res, *res0;
+ int error;
+
+ if (initialised) return name_buf;
+
+ initialised = 1;
strcpy(name_buf,def);
- if (getpeername(fd, &sa, &length)) {
- exit_cleanup(1);
+ if (getpeername(fd, (struct sockaddr *)&ss, &length)) {
+ /* FIXME: Can we really not continue? */
+ rprintf(FERROR, RSYNC_NAME ": getpeername on fd%d failed: %s\n",
+ fd, strerror(errno));
+ exit_cleanup(RERR_SOCKETIO);
}
- /* Look up the remote host name. */
- if ((hp = gethostbyaddr((char *) &sockin->sin_addr,
- sizeof(sockin->sin_addr),
- AF_INET))) {
- strlcpy(name_buf,(char *)hp->h_name,sizeof(name_buf) - 1);
+#ifdef INET6
+ if (ss.sa_family == AF_INET6 &&
+ IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)&ss)->sin6_addr)) {
+ struct sockaddr_in6 sin6;
+ struct sockaddr_in *sin;
+
+ memcpy(&sin6, &ss, sizeof(sin6));
+ sin = (struct sockaddr_in *)&ss;
+ memset(sin, 0, sizeof(*sin));
+ sin->sin_family = AF_INET;
+ length = sizeof(struct sockaddr_in);
+#ifdef HAVE_SOCKADDR_LEN
+ sin->sin_len = length;
+#endif
+ sin->sin_port = sin6.sin6_port;
+ memcpy(&sin->sin_addr, &sin6.sin6_addr.s6_addr[12],
+ sizeof(sin->sin_addr));
+ }
+#endif
+
+ /* reverse lookup */
+ if (getnameinfo((struct sockaddr *)&ss, length,
+ name_buf, sizeof(name_buf), port_buf, sizeof(port_buf),
+ NI_NAMEREQD | NI_NUMERICSERV) != 0) {
+ strcpy(name_buf, def);
+ rprintf(FERROR, "reverse name lookup failed\n");
}
+ /* forward lookup */
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_family = PF_UNSPEC;
+ hints.ai_flags = AI_CANONNAME;
+ hints.ai_socktype = SOCK_STREAM;
+ error = getaddrinfo(name_buf, port_buf, &hints, &res0);
+ if (error) {
+ strcpy(name_buf, def);
+ rprintf(FERROR,
+ RSYNC_NAME ": forward name lookup for %s failed: %s\n",
+ port_buf,
+ gai_strerror(error));
+ return name_buf;
+ }
- /* do a forward lookup as well to prevent spoofing */
- hp = gethostbyname(name_buf);
- if (!hp) {
- strcpy(name_buf,def);
- rprintf(FERROR,"reverse name lookup failed\n");
- } else {
- for (p=hp->h_addr_list;*p;p++) {
- if (memcmp(*p, &sockin->sin_addr, hp->h_length) == 0) {
- break;
- }
- }
- if (!*p) {
- strcpy(name_buf,def);
- rprintf(FERROR,"reverse name lookup mismatch - spoofed address?\n");
- }
+ /* XXX sin6_flowinfo and other fields */
+ for (res = res0; res; res = res->ai_next) {
+ if (res->ai_family != ss.sa_family)
+ continue;
+ if (res->ai_addrlen != length)
+ continue;
+ if (memcmp(res->ai_addr, &ss, res->ai_addrlen) == 0)
+ break;
+ }
+
+ /* TODO: Do a forward lookup as well to prevent spoofing */
+
+ if (res == NULL) {
+ strcpy(name_buf, def);
+ rprintf(FERROR, RSYNC_NAME ": "
+ "reverse name lookup mismatch on fd%d - spoofed address?\n",
+ fd);
}
+ freeaddrinfo(res0);
return name_buf;
}
+
+
+/*******************************************************************
+this is like socketpair but uses tcp. It is used by the Samba
+regression test code
+The function guarantees that nobody else can attach to the socket,
+or if they do that this function fails and the socket gets closed
+returns 0 on success, -1 on failure
+the resulting file descriptors are symmetrical
+ ******************************************************************/
+static int socketpair_tcp(int fd[2])
+{
+ int listener;
+ struct sockaddr_in sock;
+ struct sockaddr_in sock2;
+ socklen_t socklen = sizeof(sock);
+ int connect_done = 0;
+
+ fd[0] = fd[1] = listener = -1;
+
+ memset(&sock, 0, sizeof(sock));
+
+ if ((listener = socket(PF_INET, SOCK_STREAM, 0)) == -1) goto failed;
+
+ memset(&sock2, 0, sizeof(sock2));
+#ifdef HAVE_SOCK_SIN_LEN
+ sock2.sin_len = sizeof(sock2);
+#endif
+ sock2.sin_family = PF_INET;
+
+ bind(listener, (struct sockaddr *)&sock2, sizeof(sock2));
+
+ if (listen(listener, 1) != 0) goto failed;
+
+ if (getsockname(listener, (struct sockaddr *)&sock, &socklen) != 0) goto failed;
+
+ if ((fd[1] = socket(PF_INET, SOCK_STREAM, 0)) == -1) goto failed;
+
+ set_nonblocking(fd[1]);
+
+ sock.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+
+ if (connect(fd[1],(struct sockaddr *)&sock,sizeof(sock)) == -1) {
+ if (errno != EINPROGRESS) goto failed;
+ } else {
+ connect_done = 1;
+ }
+
+ if ((fd[0] = accept(listener, (struct sockaddr *)&sock, &socklen)) == -1) goto failed;
+
+ close(listener);
+ if (connect_done == 0) {
+ if (connect(fd[1],(struct sockaddr *)&sock,sizeof(sock)) != 0
+ && errno != EISCONN) goto failed;
+ }
+
+ set_blocking (fd[1]);
+
+ /* all OK! */
+ return 0;
+
+ failed:
+ if (fd[0] != -1) close(fd[0]);
+ if (fd[1] != -1) close(fd[1]);
+ if (listener != -1) close(listener);
+ return -1;
+}
+
+
+/*******************************************************************
+run a program on a local tcp socket, this is used to launch smbd
+when regression testing
+the return value is a socket which is attached to a subprocess
+running "prog". stdin and stdout are attached. stderr is left
+attached to the original stderr
+ ******************************************************************/
+int sock_exec(const char *prog)
+{
+ int fd[2];
+ if (socketpair_tcp(fd) != 0) {
+ rprintf (FERROR, RSYNC_NAME
+ ": socketpair_tcp failed (%s)\n",
+ strerror(errno));
+ return -1;
+ }
+ if (fork() == 0) {
+ close(fd[0]);
+ close(0);
+ close(1);
+ dup(fd[1]);
+ dup(fd[1]);
+ if (verbose > 3)
+ fprintf (stderr,
+ RSYNC_NAME ": execute socket program \"%s\"\n",
+ prog);
+ exit (system (prog));
+ }
+ close (fd[1]);
+ return fd[0];
+}
+
+
+