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"
47 * Number of seconds ssh has to start up
49 #define CONNECT_TIMEOUT 20
52 * Magic values for ssh_conn->handle
54 #define H_TAKEN -1 /* ssh_conn->tok was already read */
55 #define H_EOF -2 /* this connection has been shut down */
60 static void ssh_connect(const char *, char *(*)(char *, void *),
61 void (*)(void *, security_handle_t *, security_status_t),
65 * This is our interface to the outside world.
67 const security_driver_t ssh_security_driver = {
74 stream_recvpkt_cancel,
83 tcpm_stream_read_sync,
84 tcpm_stream_read_cancel,
85 tcpm_close_connection,
90 static int newhandle = 1;
95 static int runssh(struct tcp_conn *, const char *, const char *, const char *);
98 * ssh version of a security handle allocator. Logically sets
99 * up a network "connection".
103 const char * hostname,
104 char * (*conf_fn)(char *, void *),
105 void (*fn)(void *, security_handle_t *, security_status_t),
110 struct sec_handle *rh;
111 char *amandad_path=NULL, *client_username=NULL, *ssh_keys=NULL;
114 assert(hostname != NULL);
116 auth_debug(1, "ssh_connect: %s\n", hostname);
118 rh = alloc(SIZEOF(*rh));
119 security_handleinit(&rh->sech, &ssh_security_driver);
122 rh->ev_timeout = NULL;
125 /* get the canonical hostname */
127 if ((result = resolve_hostname(hostname, 0, NULL, &rh->hostname)) != 0
128 || rh->hostname == NULL) {
129 security_seterror(&rh->sech,
130 _("ssh_security could not find canonical name for '%s': %s"),
131 hostname, gai_strerror(result));
132 (*fn)(arg, &rh->sech, S_ERROR);
135 rh->rs = tcpma_stream_client(rh, newhandle++);
136 rh->rc->conf_fn = conf_fn;
137 rh->rc->datap = datap;
142 amfree(rh->hostname);
143 rh->hostname = stralloc(rh->rs->rc->hostname);
146 * We need to open a new connection.
148 * XXX need to eventually limit number of outgoing connections here.
151 amandad_path = conf_fn("amandad_path", datap);
152 client_username = conf_fn("client_username", datap);
153 ssh_keys = conf_fn("ssh_keys", datap);
155 if(rh->rc->read == -1) {
156 if (runssh(rh->rs->rc, amandad_path, client_username, ssh_keys) < 0) {
157 security_seterror(&rh->sech, _("can't connect to %s: %s"),
158 hostname, rh->rs->rc->errmsg);
165 * The socket will be opened async so hosts that are down won't
166 * block everything. We need to register a write event
167 * so we will know when the socket comes alive.
169 * Overload rh->rs->ev_read to provide a write event handle.
170 * We also register a timeout.
174 rh->rs->ev_read = event_register((event_id_t)rh->rs->rc->write, EV_WRITEFD,
175 sec_connect_callback, rh);
176 rh->ev_timeout = event_register((event_id_t)CONNECT_TIMEOUT, EV_TIME,
177 sec_connect_timeout, rh);
182 (*fn)(arg, &rh->sech, S_ERROR);
186 * Forks a ssh to the host listed in rc->hostname
187 * Returns negative on error, with an errmsg in rc->errmsg.
191 struct tcp_conn * rc,
192 const char * amandad_path,
193 const char * client_username,
194 const char * ssh_keys)
196 int rpipe[2], wpipe[2];
197 char *xamandad_path = (char *)amandad_path;
198 char *xclient_username = (char *)client_username;
199 char *xssh_keys = (char *)ssh_keys;
201 memset(rpipe, -1, SIZEOF(rpipe));
202 memset(wpipe, -1, SIZEOF(wpipe));
203 if (pipe(rpipe) < 0 || pipe(wpipe) < 0) {
204 rc->errmsg = newvstrallocf(rc->errmsg, _("pipe: %s"), strerror(errno));
208 switch (rc->pid = fork()) {
210 rc->errmsg = newvstrallocf(rc->errmsg, _("fork: %s"), strerror(errno));
223 rc->write = wpipe[1];
230 if(!xamandad_path || strlen(xamandad_path) <= 1)
231 xamandad_path = vstralloc(amlibexecdir, "/", "amandad",
232 versionsuffix(), NULL);
233 if(!xclient_username || strlen(xclient_username) <= 1)
234 xclient_username = CLIENT_LOGIN;
235 if(!ssh_keys || strlen(ssh_keys) <= 1) {
236 execlp(SSH, SSH, SSH_OPTIONS, "-l", xclient_username,
237 rc->hostname, xamandad_path, "-auth=ssh", "amdump", "amindexd",
238 "amidxtaped", (char *)NULL);
241 execlp(SSH, SSH, SSH_OPTIONS, "-l", xclient_username,
242 "-i", xssh_keys, rc->hostname, xamandad_path, "-auth=ssh",
243 "amdump", "amindexd", "amidxtaped", (char *)NULL);
245 error("error: couldn't exec %s: %s", SSH, strerror(errno));
247 /* should never go here, shut up compiler warning */