Imported Upstream version 3.2.0

[debian/amanda] / common-src / ssh-security.c

diff --git a/common-src/ssh-security.c b/common-src/ssh-security.c
index 19d60692792725905a82e3e4465555201db8fa1c..bed501be996151a31ca54560b8b1513b7de975e9 100644 (file)
--- a/common-src/ssh-security.c
+++ b/common-src/ssh-security.c
@@ -39,6 +39,7 @@
 #include "packet.h"
 #include "security.h"
 #include "security-util.h"
+#include "sockaddr-util.h"
 #include "stream.h"
 
 /*
@@ -58,6 +59,10 @@
 static void    ssh_connect(const char *, char *(*)(char *, void *),
                        void (*)(void *, security_handle_t *, security_status_t),
                        void *, void *);
+static void ssh_accept(const security_driver_t *driver, char *(*conf_fn)(char *, void *),
+                       int in, int out,
+                       void (*fn)(security_handle_t *, pkt_t *),
+                       void *datap);
 
 /*
  * This is our interface to the outside world.
@@ -65,7 +70,8 @@ static void   ssh_connect(const char *, char *(*)(char *, void *),
 const security_driver_t ssh_security_driver = {
     "SSH",
     ssh_connect,
-    sec_accept,
+    ssh_accept,
+    sec_get_authenticated_peer_name_hostname,
     sec_close,
     stream_sendpkt,
     stream_recvpkt,
@@ -113,7 +119,7 @@ ssh_connect(
 
     auth_debug(1, "ssh_connect: %s\n", hostname);
 
-    rh = alloc(SIZEOF(*rh));
+    rh = g_new0(struct sec_handle, 1);
     security_handleinit(&rh->sech, &ssh_security_driver);
     rh->hostname = NULL;
     rh->rs = NULL;
@@ -180,6 +186,99 @@ error:
     (*fn)(arg, &rh->sech, S_ERROR);
 }
 
+/* like sec_accept, but first it gets the remote system's hostname */
+static void
+ssh_accept(
+    const security_driver_t *driver,
+    char       *(*conf_fn)(char *, void *),
+    int                in,
+    int                out,
+    void       (*fn)(security_handle_t *, pkt_t *),
+    void       *datap)
+{
+    struct sec_handle *rh;
+    struct tcp_conn *rc = sec_tcp_conn_get("", 0);
+    char *ssh_connection, *p;
+    char *errmsg = NULL;
+    sockaddr_union addr;
+    int result;
+
+    /* "Accepting" an SSH connection means that amandad was invoked via sshd, so
+     * we should have anSSH_CONNECTION env var.  If not, then this probably isn't
+     * a real SSH connection and we should bail out. */
+    ssh_connection = getenv("SSH_CONNECTION");
+    if (!ssh_connection) {
+       errmsg = g_strdup("$SSH_CONNECTION not set - was amandad started by sshd?");
+       goto error;
+    }
+
+    /* make a local copy, to munge */
+    ssh_connection = g_strdup(ssh_connection);
+
+    /* strip off the first component - the ASCII IP address */
+    if ((p = strchr(ssh_connection, ' ')) == NULL) {
+       errmsg = g_strdup("$SSH_CONNECTION malformed");
+       goto error;
+    }
+    *p = '\0';
+
+    /* ---- everything from here on is just a warning, leaving hostname at "" */
+
+    SU_INIT(&addr, AF_INET);
+
+    /* turn the string address into a sockaddr */
+    if ((result = str_to_sockaddr(ssh_connection, &addr)) != 1) {
+       if (result == 0) {
+           g_warning("Could not parse peer address %s", ssh_connection);
+       } else {
+           g_warning("Parsing peer address %s: %s", ssh_connection, gai_strerror(result));
+       }
+       goto done;
+    }
+
+    /* find the hostname */
+    result = getnameinfo((struct sockaddr *)&addr, SS_LEN(&addr),
+                rc->hostname, sizeof(rc->hostname), NULL, 0, 0);
+    if (result != 0) {
+       g_warning("Could not get hostname for SSH client %s: %s", ssh_connection,
+               gai_strerror(result));
+       goto done;
+    }
+
+    /* and verify it */
+    if (check_name_give_sockaddr(rc->hostname,
+                                (struct sockaddr *)&addr, &errmsg) < 0) {
+       rc->hostname[0] = '\0'; /* null out the bad hostname */
+       g_warning("Checking SSH client DNS: %s", errmsg);
+       amfree(errmsg);
+       goto done;
+    }
+
+done:
+    if (ssh_connection)
+       g_free(ssh_connection);
+
+    rc->read = in;
+    rc->write = out;
+    rc->accept_fn = fn;
+    rc->driver = driver;
+    rc->conf_fn = conf_fn;
+    rc->datap = datap;
+    sec_tcp_conn_read(rc);
+    return;
+
+error:
+    if (ssh_connection)
+       g_free(ssh_connection);
+
+    /* make up a fake handle for the error */
+    rh = g_new0(struct sec_handle, 1);
+    security_handleinit(&rh->sech, driver);
+    security_seterror((security_handle_t*)rh, "ssh_accept: %s", errmsg);
+    amfree(errmsg);
+    (*fn)(&rh->sech, NULL);
+}
+
 /*
  * Forks a ssh to the host listed in rc->hostname
  * Returns negative on error, with an errmsg in rc->errmsg.