Initial revision

[gssapi-openssh.git] / openssh / auth2-pam.c

diff --git a/openssh/auth2-pam.c b/openssh/auth2-pam.c
new file mode 100644 (file)
index 0000000..b6eaf08
--- /dev/null
+++ b/openssh/auth2-pam.c
@@ -0,0 +1,158 @@
+#include "includes.h"
+RCSID("$Id$");
+
+#ifdef USE_PAM
+#include <security/pam_appl.h>
+
+#include "ssh.h"
+#include "ssh2.h"
+#include "auth.h"
+#include "auth-pam.h"
+#include "packet.h"
+#include "xmalloc.h"
+#include "dispatch.h"
+#include "log.h"
+
+static int do_pam_conversation_kbd_int(int num_msg, 
+    const struct pam_message **msg, struct pam_response **resp, 
+    void *appdata_ptr);
+void input_userauth_info_response_pam(int type, int plen, void *ctxt);
+
+struct {
+       int finished, num_received, num_expected;
+       int *prompts;
+       struct pam_response *responses;
+} context_pam2 = {0, 0, 0, NULL};
+
+static struct pam_conv conv2 = {
+       do_pam_conversation_kbd_int,
+       NULL,
+};
+
+int
+auth2_pam(Authctxt *authctxt)
+{
+       int retval = -1;
+
+       if (authctxt->user == NULL)
+               fatal("auth2_pam: internal error: no user");
+
+       conv2.appdata_ptr = authctxt;
+       do_pam_set_conv(&conv2);
+
+       dispatch_set(SSH2_MSG_USERAUTH_INFO_RESPONSE,
+           &input_userauth_info_response_pam);
+       retval = (do_pam_authenticate(0) == PAM_SUCCESS);
+       dispatch_set(SSH2_MSG_USERAUTH_INFO_RESPONSE, NULL);
+
+       return retval;
+}
+
+static int
+do_pam_conversation_kbd_int(int num_msg, const struct pam_message **msg,
+    struct pam_response **resp, void *appdata_ptr)
+{
+       int i, j, done;
+       char *text;
+
+       context_pam2.finished = 0;
+       context_pam2.num_received = 0;
+       context_pam2.num_expected = 0;
+       context_pam2.prompts = xmalloc(sizeof(int) * num_msg);
+       context_pam2.responses = xmalloc(sizeof(struct pam_response) * num_msg);
+       memset(context_pam2.responses, 0, sizeof(struct pam_response) * num_msg);
+
+       text = NULL;
+       for (i = 0, context_pam2.num_expected = 0; i < num_msg; i++) {
+               int style = PAM_MSG_MEMBER(msg, i, msg_style);
+               switch (style) {
+               case PAM_PROMPT_ECHO_ON:
+               case PAM_PROMPT_ECHO_OFF:
+                       context_pam2.num_expected++;
+                       break;
+               case PAM_TEXT_INFO:
+               case PAM_ERROR_MSG:
+               default:
+                       /* Capture all these messages to be sent at once */
+                       message_cat(&text, PAM_MSG_MEMBER(msg, i, msg));
+                       break;
+               }
+       }
+
+       if (context_pam2.num_expected == 0)
+               return PAM_SUCCESS;
+
+       packet_start(SSH2_MSG_USERAUTH_INFO_REQUEST);
+       packet_put_cstring(""); /* Name */
+       packet_put_cstring(""); /* Instructions */
+       packet_put_cstring(""); /* Language */
+       packet_put_int(context_pam2.num_expected);
+       
+       for (i = 0, j = 0; i < num_msg; i++) {
+               int style = PAM_MSG_MEMBER(msg, i, msg_style);
+               
+               /* Skip messages which don't need a reply */
+               if (style != PAM_PROMPT_ECHO_ON && style != PAM_PROMPT_ECHO_OFF)
+                       continue;
+               
+               context_pam2.prompts[j++] = i;
+               if (text) {
+                       message_cat(&text, PAM_MSG_MEMBER(msg, i, msg));
+                       packet_put_cstring(text);
+                       text = NULL;
+               } else
+                       packet_put_cstring(PAM_MSG_MEMBER(msg, i, msg));
+               packet_put_char(style == PAM_PROMPT_ECHO_ON);
+       }
+       packet_send();
+       packet_write_wait();
+
+       /*
+        * Grabbing control of execution and spinning until we get what
+        * we want is probably rude, but it seems to work properly, and
+        * the client *should* be in lock-step with us, so the loop should
+        * only be traversed once.
+        */
+       while(context_pam2.finished == 0) {
+               done = 1;
+               dispatch_run(DISPATCH_BLOCK, &done, appdata_ptr);
+               if(context_pam2.finished == 0)
+                       debug("extra packet during conversation");
+       }
+
+       if(context_pam2.num_received == context_pam2.num_expected) {
+               *resp = context_pam2.responses;
+               return PAM_SUCCESS;
+       } else
+               return PAM_CONV_ERR;
+}
+
+void
+input_userauth_info_response_pam(int type, int plen, void *ctxt)
+{
+       Authctxt *authctxt = ctxt;
+       unsigned int nresp = 0, rlen = 0, i = 0;
+       char *resp;
+
+       if (authctxt == NULL)
+               fatal("input_userauth_info_response_pam: no authentication context");
+
+       nresp = packet_get_int();       /* Number of responses. */
+       debug("got %d responses", nresp);
+
+       for (i = 0; i < nresp; i++) {
+               int j = context_pam2.prompts[i];
+
+               resp = packet_get_string(&rlen);
+               context_pam2.responses[j].resp_retcode = PAM_SUCCESS;
+               context_pam2.responses[j].resp = xstrdup(resp);
+               xfree(resp);
+               context_pam2.num_received++;
+       }
+
+       context_pam2.finished = 1;
+
+       packet_done();
+}
+
+#endif