2 * Amanda, The Advanced Maryland Automatic Network Disk Archiver
3 * Copyright (c) 1999 University of Maryland
6 * Permission to use, copy, modify, distribute, and sell this software and its
7 * documentation for any purpose is hereby granted without fee, provided that
8 * the above copyright notice appear in all copies and that both that
9 * copyright notice and this permission notice appear in supporting
10 * documentation, and that the name of U.M. not be used in advertising or
11 * publicity pertaining to distribution of the software without specific,
12 * written prior permission. U.M. makes no representations about the
13 * suitability of this software for any purpose. It is provided "as is"
14 * without express or implied warranty.
16 * U.M. DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL U.M.
18 * BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
19 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
20 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
21 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
23 * Authors: the Amanda Development Team. Its members are listed in a
24 * file named AUTHORS, in the root directory of this distribution.
28 * $Id: ssh-security.c,v 1.23 2006/08/21 20:17:10 martinea Exp $
30 * ssh-security.c - security and transport over ssh or a ssh-like command.
32 * XXX still need to check for initial keyword on connect so we can skip
33 * over shell garbage and other stuff that ssh might want to spew out.
42 #include "security-util.h"
49 * Number of seconds ssh has to start up
51 #define CONNECT_TIMEOUT 20
54 * Magic values for ssh_conn->handle
56 #define H_TAKEN -1 /* ssh_conn->tok was already read */
57 #define H_EOF -2 /* this connection has been shut down */
62 static void ssh_connect(const char *, char *(*)(char *, void *),
63 void (*)(void *, security_handle_t *, security_status_t),
67 * This is our interface to the outside world.
69 const security_driver_t ssh_security_driver = {
76 stream_recvpkt_cancel,
85 tcpm_stream_read_sync,
86 tcpm_stream_read_cancel,
87 tcpm_close_connection,
92 static int newhandle = 1;
97 static int runssh(struct tcp_conn *, const char *, const char *, const char *);
100 * ssh version of a security handle allocator. Logically sets
101 * up a network "connection".
105 const char * hostname,
106 char * (*conf_fn)(char *, void *),
107 void (*fn)(void *, security_handle_t *, security_status_t),
111 struct sec_handle *rh;
112 char *amandad_path=NULL, *client_username=NULL, *ssh_keys=NULL;
115 assert(hostname != NULL);
117 (void)conf_fn; /* Quiet unused parameter warning */
119 auth_debug(1, ("%s: ssh: ssh_connect: %s\n", debug_prefix_time(NULL),
122 rh = alloc(SIZEOF(*rh));
123 security_handleinit(&rh->sech, &ssh_security_driver);
126 rh->ev_timeout = NULL;
130 if (try_resolving_hostname(hostname, &rh->hostname)) {
131 security_seterror(&rh->sech,
132 "%s: ssh could not resolve hostname", hostname);
133 (*fn)(arg, &rh->sech, S_ERROR);
136 rh->rs = tcpma_stream_client(rh, newhandle++);
141 amfree(rh->hostname);
142 rh->hostname = stralloc(rh->rs->rc->hostname);
145 * We need to open a new connection.
147 * XXX need to eventually limit number of outgoing connections here.
150 amandad_path = conf_fn("amandad_path", datap);
151 client_username = conf_fn("client_username", datap);
152 ssh_keys = conf_fn("ssh_keys", datap);
154 if(rh->rc->read == -1) {
155 if (runssh(rh->rs->rc, amandad_path, client_username, ssh_keys) < 0) {
156 security_seterror(&rh->sech, "can't connect to %s: %s",
157 hostname, rh->rs->rc->errmsg);
164 * The socket will be opened async so hosts that are down won't
165 * block everything. We need to register a write event
166 * so we will know when the socket comes alive.
168 * Overload rh->rs->ev_read to provide a write event handle.
169 * We also register a timeout.
173 rh->rs->ev_read = event_register((event_id_t)rh->rs->rc->write, EV_WRITEFD,
174 sec_connect_callback, rh);
175 rh->ev_timeout = event_register((event_id_t)CONNECT_TIMEOUT, EV_TIME,
176 sec_connect_timeout, rh);
181 (*fn)(arg, &rh->sech, S_ERROR);
185 * Forks a ssh to the host listed in rc->hostname
186 * Returns negative on error, with an errmsg in rc->errmsg.
190 struct tcp_conn * rc,
191 const char * amandad_path,
192 const char * client_username,
193 const char * ssh_keys)
195 int rpipe[2], wpipe[2];
196 char *xamandad_path = (char *)amandad_path;
197 char *xclient_username = (char *)client_username;
198 char *xssh_keys = (char *)ssh_keys;
200 memset(rpipe, -1, SIZEOF(rpipe));
201 memset(wpipe, -1, SIZEOF(wpipe));
202 if (pipe(rpipe) < 0 || pipe(wpipe) < 0) {
203 rc->errmsg = newvstralloc(rc->errmsg, "pipe: ", strerror(errno), NULL);
207 switch (rc->pid = fork()) {
209 rc->errmsg = newvstralloc(rc->errmsg, "fork: ", strerror(errno), NULL);
222 rc->write = wpipe[1];
229 if(!xamandad_path || strlen(xamandad_path) <= 1)
230 xamandad_path = vstralloc(libexecdir, "/", "amandad",
231 versionsuffix(), NULL);
232 if(!xclient_username || strlen(xclient_username) <= 1)
233 xclient_username = CLIENT_LOGIN;
234 if(!ssh_keys || strlen(ssh_keys) <= 1) {
235 execlp(SSH, SSH, SSH_OPTIONS, "-l", xclient_username,
236 rc->hostname, xamandad_path, "-auth=ssh", "amdump", "amindexd",
237 "amidxtaped", (char *)NULL);
240 execlp(SSH, SSH, SSH_OPTIONS, "-l", xclient_username,
241 "-i", xssh_keys, rc->hostname, xamandad_path, "-auth=ssh",
242 "amdump", "amindexd", "amidxtaped", (char *)NULL);
244 error("error: couldn't exec %s: %s", SSH, strerror(errno));
246 /* should never go here, shut up compiler warning */
250 #endif /* SSH_SECURITY */