- djm@cvs.openbsd.org 2004/06/17 15:10:14

     [clientloop.c misc.h readconf.c readpass.c ssh.c ssh_config.5]
     Add option for confirmation (ControlMaster=ask) via ssh-askpass before
     opening shared connections; ok markus@

diff --git a/ChangeLog b/ChangeLog
index f08d4f82224d412eac35f95abb2778ada0164d19..e7105f670e619e6a4d89dff3a1d7d611778ff27b 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -3,6 +3,10 @@
    - djm@cvs.openbsd.org 2004/06/17 14:52:48
      [clientloop.c clientloop.h ssh.c]
      support environment passing over shared connections; ok markus@
+   - djm@cvs.openbsd.org 2004/06/17 15:10:14
+     [clientloop.c misc.h readconf.c readpass.c ssh.c ssh_config.5]
+     Add option for confirmation (ControlMaster=ask) via ssh-askpass before 
+     opening shared connections; ok markus@
 
 20040617
  - (dtucker) [regress/scp.sh] diff -N is not portable (but needed for some

diff --git a/clientloop.c b/clientloop.c
index eb320033130c22fccebdca0b19a60314008059ec..8f2f270d7d91fe990f977b5df6114a1cdd67a9d9 100644 (file)
--- a/clientloop.c
+++ b/clientloop.c
@@ -59,7 +59,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: clientloop.c,v 1.126 2004/06/17 14:52:48 djm Exp $");
+RCSID("$OpenBSD: clientloop.c,v 1.127 2004/06/17 15:10:13 djm Exp $");
 
 #include "ssh.h"
 #include "ssh1.h"
@@ -549,7 +549,7 @@ client_extra_session2_setup(int id, void *arg)
        client_session2_setup(id, cctx->want_tty, cctx->want_subsys, 
            cctx->term, &cctx->tio, c->rfd, &cctx->cmd, cctx->env,
            client_subsystem_reply);
-       
+
        c->confirm_ctx = NULL;
        buffer_free(&cctx->cmd);
        xfree(cctx->term);
@@ -566,7 +566,7 @@ client_process_control(fd_set * readset)
 {
        Buffer m;
        Channel *c;
-       int client_fd, new_fd[3], ver, i;
+       int client_fd, new_fd[3], ver, i, allowed;
        socklen_t addrlen;
        struct sockaddr_storage addr;
        struct confirm_ctx *cctx;
@@ -600,23 +600,52 @@ client_process_control(fd_set * readset)
                close(client_fd);
                return;
        }
-       /* XXX: implement use of ssh-askpass to confirm additional channels */
+
+       allowed = 1;
+       if (options.control_master == 2) {
+               char *p, prompt[1024];
+
+               allowed = 0;
+               snprintf(prompt, sizeof(prompt),
+                   "Allow shared connection to %s? ", host);
+               p = read_passphrase(prompt, RP_USE_ASKPASS|RP_ALLOW_EOF);
+               if (p != NULL) {
+                       /*
+                        * Accept empty responses and responses consisting
+                        * of the word "yes" as affirmative.
+                        */
+                       if (*p == '\0' || *p == '\n' || 
+                           strcasecmp(p, "yes") == 0)
+                               allowed = 1;
+                       xfree(p);
+               }
+       }
 
        unset_nonblock(client_fd);
 
        buffer_init(&m);
 
+       buffer_put_int(&m, allowed);
        buffer_put_int(&m, getpid());
        if (ssh_msg_send(client_fd, /* version */0, &m) == -1) {
                error("%s: client msg_send failed", __func__);
                close(client_fd);
+               buffer_free(&m);
                return;
        }
        buffer_clear(&m);
 
+       if (!allowed) {
+               error("Refused control connection");
+               close(client_fd);
+               buffer_free(&m);
+               return;
+       }
+
        if (ssh_msg_recv(client_fd, &m) == -1) {
                error("%s: client msg_recv failed", __func__);
                close(client_fd);
+               buffer_free(&m);
                return;
        }
 
@@ -670,6 +699,7 @@ client_process_control(fd_set * readset)
                close(new_fd[0]);
                close(new_fd[1]);
                close(new_fd[2]);
+               buffer_free(&m);
                return;
        }
        buffer_free(&m);

diff --git a/misc.h b/misc.h
index 6a4eff1369722f0490acb44196ad5bb699da40cf..ffa8d8f27bdb1acdc3ef468a451419e78b4ca488 100644 (file)
--- a/misc.h
+++ b/misc.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: misc.h,v 1.15 2004/06/14 01:44:39 djm Exp $   */
+/*     $OpenBSD: misc.h,v 1.16 2004/06/17 15:10:14 djm Exp $   */
 
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
@@ -43,5 +43,6 @@ char  *tilde_expand_filename(const char *, uid_t);
 #define RP_ECHO                        0x0001
 #define RP_ALLOW_STDIN         0x0002
 #define RP_ALLOW_EOF           0x0004
+#define RP_USE_ASKPASS         0x0008
 
 char   *read_passphrase(const char *, int);

diff --git a/readconf.c b/readconf.c
index 2b1d7cc46d33aa4260bb0e56e98b004c334161a4..429f691292e733754ccf32bb95afac64f7d9dc7a 100644 (file)
--- a/readconf.c
+++ b/readconf.c
@@ -12,7 +12,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: readconf.c,v 1.132 2004/06/13 15:03:02 djm Exp $");
+RCSID("$OpenBSD: readconf.c,v 1.133 2004/06/17 15:10:14 djm Exp $");
 
 #include "ssh.h"
 #include "xmalloc.h"
@@ -772,7 +772,7 @@ parse_int:
 
        case oControlMaster:
                intptr = &options->control_master;
-               goto parse_flag;
+               goto parse_yesnoask;
 
        case oDeprecated:
                debug("%s line %d: Deprecated option \"%s\"",

diff --git a/readpass.c b/readpass.c
index fc7629c37e6d3f51e8ad46aff2671bd66f81f371..eb4f6fdb6d903aa29b533e42b315b150a2f9a3ca 100644 (file)
--- a/readpass.c
+++ b/readpass.c
@@ -23,7 +23,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: readpass.c,v 1.29 2004/05/08 00:21:31 djm Exp $");
+RCSID("$OpenBSD: readpass.c,v 1.30 2004/06/17 15:10:14 djm Exp $");
 
 #include "xmalloc.h"
 #include "misc.h"
@@ -103,7 +103,9 @@ read_passphrase(const char *prompt, int flags)
        int rppflags, use_askpass = 0, ttyfd;
 
        rppflags = (flags & RP_ECHO) ? RPP_ECHO_ON : RPP_ECHO_OFF;
-       if (flags & RP_ALLOW_STDIN) {
+       if (flags & RP_USE_ASKPASS)
+               use_askpass = 1;
+       else if (flags & RP_ALLOW_STDIN) {
                if (!isatty(STDIN_FILENO))
                        use_askpass = 1;
        } else {
@@ -115,6 +117,9 @@ read_passphrase(const char *prompt, int flags)
                        use_askpass = 1;
        }
 
+       if ((flags & RP_USE_ASKPASS) && getenv("DISPLAY") == NULL)
+               return (flags & RP_ALLOW_EOF) ? NULL : xstrdup("");
+
        if (use_askpass && getenv("DISPLAY")) {
                if (getenv(SSH_ASKPASS_ENV))
                        askpass = getenv(SSH_ASKPASS_ENV);

diff --git a/ssh.c b/ssh.c
index 9b434b93ecc0ef042591ce77f44555727b4682ac..6f8114d53b063dba464adac309481e4321daa432 100644 (file)
--- a/ssh.c
+++ b/ssh.c
@@ -40,7 +40,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: ssh.c,v 1.215 2004/06/17 14:52:48 djm Exp $");
+RCSID("$OpenBSD: ssh.c,v 1.216 2004/06/17 15:10:14 djm Exp $");
 
 #include <openssl/evp.h>
 #include <openssl/err.h>
@@ -1044,7 +1044,7 @@ ssh_control_listener(void)
        mode_t old_umask;
        int addr_len;
 
-       if (options.control_path == NULL || options.control_master != 1)
+       if (options.control_path == NULL || options.control_master <= 0)
                return;
 
        memset(&addr, '\0', sizeof(addr));
@@ -1266,6 +1266,9 @@ control_client(const char *path)
                fatal("%s: msg_recv", __func__);
        if (buffer_get_char(&m) != 0)
                fatal("%s: wrong version", __func__);
+       /* Connection allowed? */
+       if (buffer_get_int(&m) != 1)
+               fatal("Connection to master denied");
        control_server_pid = buffer_get_int(&m);
 
        buffer_clear(&m);

diff --git a/ssh_config.5 b/ssh_config.5
index bab11d313a928e1dafc29b102c290bb752b5ac7e..3e8c1db069ed69cf94c27d8bb0e2f49d223458be 100644 (file)
--- a/ssh_config.5
+++ b/ssh_config.5
@@ -34,7 +34,7 @@
 .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 .\"
-.\" $OpenBSD: ssh_config.5,v 1.36 2004/06/13 15:03:02 djm Exp $
+.\" $OpenBSD: ssh_config.5,v 1.37 2004/06/17 15:10:14 djm Exp $
 .Dd September 25, 1999
 .Dt SSH_CONFIG 5
 .Os
@@ -273,6 +273,15 @@ set to
 (the default.)
 These sessions will reuse the master instance's network connection rather
 than initiating new ones.
+Setting this to
+.Dq ask
+will cause
+.Nm ssh
+to listen for control connections, but require confirmation using the
+.Ev SSH_ASKPASS
+program before they are accepted (see
+.Xr ssh-add 1
+for details)
 .It Cm ControlPath
 Specify a the path to the control socket used for connection sharing.
 See