1 files changed, 165 insertions, 0 deletions

diff --git a/auth2-pam.c b/auth2-pam.c
new file mode 100644
index 000000000..ac28fb245
--- /dev/null
+++ b/auth2-pam.c
@@ -0,0 +1,165 @@
+#include "includes.h"
+RCSID("$Id: auth2-pam.c,v 1.15 2003/01/08 01:37:03 djm Exp $");
+
+#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, u_int32_t seqnr, 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, u_int32_t seqnr, 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);
+
+
+        if (nresp != context_pam2.num_expected)
+                fatal("%s: Received incorrect number of responses "
+                    "(expected %d, received %u)", __func__, 
+                    context_pam2.num_expected, nresp);
+
+        if (nresp > 100)
+                fatal("%s: too many replies", __func__);
+
+        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 = resp;
+                context_pam2.num_received++;
+        }
+
+        context_pam2.finished = 1;
+
+        packet_check_eom();
+}
+#endif