1 files changed, 110 insertions, 106 deletions

diff --git a/auth-pam.c b/auth-pam.c
index ab985d15b..e6fddecc0 100644
--- a/auth-pam.c
+++ b/auth-pam.c
@@ -28,31 +28,29 @@
 #include "ssh.h"
 #include "xmalloc.h"
 #include "log.h"
+#include "auth-pam.h"
 #include "servconf.h"
 #include "canohost.h"
 #include "readpass.h"
 
-RCSID("$Id: auth-pam.c,v 1.24 2001/02/05 12:42:17 stevesk Exp $");
+RCSID("$Id: auth-pam.c,v 1.25 2001/02/07 01:58:34 djm Exp $");
 
 #define NEW_AUTHTOK_MSG \
         "Warning: Your password has expired, please change it now"
 
-/* Callbacks */
-static int pamconv(int num_msg, const struct pam_message **msg,
-          struct pam_response **resp, void *appdata_ptr);
-void pam_cleanup_proc(void *context);
-void pam_msg_cat(const char *msg);
+static int do_pam_conversation(int num_msg, const struct pam_message **msg,
+        struct pam_response **resp, void *appdata_ptr);
 
 /* module-local variables */
 static struct pam_conv conv = {
-        pamconv,
+        do_pam_conversation,
         NULL
 };
+static char *pam_msg = NULL;
 static pam_handle_t *pamh = NULL;
 static const char *pampasswd = NULL;
-static char *pam_msg = NULL;
 
-/* states for pamconv() */
+/* states for do_pam_conversation() */
 enum { INITIAL_LOGIN, OTHER } pamstate = INITIAL_LOGIN;
 /* remember whether pam_acct_mgmt() returned PAM_NEWAUTHTOK_REQD */
 static int password_change_required = 0;
@@ -80,14 +78,14 @@ int do_pam_authenticate(int flags)
  *
  * INITIAL_LOGIN mode simply feeds the password from the client into
  * PAM in response to PAM_PROMPT_ECHO_OFF, and collects output
- * messages with pam_msg_cat().  This is used during initial
+ * messages with into pam_msg.  This is used during initial
  * authentication to bypass the normal PAM password prompt.
  *
  * OTHER mode handles PAM_PROMPT_ECHO_OFF with read_passphrase(prompt, 1)
  * and outputs messages to stderr. This mode is used if pam_chauthtok()
  * is called to update expired passwords.
  */
-static int pamconv(int num_msg, const struct pam_message **msg,
+static int do_pam_conversation(int num_msg, const struct pam_message **msg,
         struct pam_response **resp, void *appdata_ptr)
 {
         struct pam_response *reply;
@@ -100,40 +98,28 @@ static int pamconv(int num_msg, const struct pam_message **msg,
                 return PAM_CONV_ERR;
 
         for (count = 0; count < num_msg; count++) {
-                switch(PAM_MSG_MEMBER(msg, count, msg_style)) {
+                if (pamstate == INITIAL_LOGIN) {
+                        /*
+                         * We can't use stdio yet, queue messages for 
+                         * printing later
+                         */
+                        switch(PAM_MSG_MEMBER(msg, count, msg_style)) {
                         case PAM_PROMPT_ECHO_ON:
-                                if (pamstate == INITIAL_LOGIN) {
+                                free(reply);
+                                return PAM_CONV_ERR;
+                        case PAM_PROMPT_ECHO_OFF:
+                                if (pampasswd == NULL) {
                                         free(reply);
                                         return PAM_CONV_ERR;
-                                } else {
-                                        fputs(PAM_MSG_MEMBER(msg, count, msg), stderr);
-                                        fgets(buf, sizeof(buf), stdin);
-                                        reply[count].resp = xstrdup(buf);
-                                        reply[count].resp_retcode = PAM_SUCCESS;
-                                        break;
-                                }
-                        case PAM_PROMPT_ECHO_OFF:
-                                if (pamstate == INITIAL_LOGIN) {
-                                        if (pampasswd == NULL) {
-                                                free(reply);
-                                                return PAM_CONV_ERR;
-                                        }
-                                        reply[count].resp = xstrdup(pampasswd);
-                                } else {
-                                        reply[count].resp =
-                                                xstrdup(read_passphrase(PAM_MSG_MEMBER(msg, count, msg), 1));
                                 }
+                                reply[count].resp = xstrdup(pampasswd);
                                 reply[count].resp_retcode = PAM_SUCCESS;
                                 break;
                         case PAM_ERROR_MSG:
                         case PAM_TEXT_INFO:
                                 if ((*msg)[count].msg != NULL) {
-                                        if (pamstate == INITIAL_LOGIN)
-                                                pam_msg_cat(PAM_MSG_MEMBER(msg, count, msg));
-                                        else {
-                                                fputs(PAM_MSG_MEMBER(msg, count, msg), stderr);
-                                                fputs("\n", stderr);
-                                        }
+                                        message_cat(&pam_msg, 
+                                            PAM_MSG_MEMBER(msg, count, msg));
                                 }
                                 reply[count].resp = xstrdup("");
                                 reply[count].resp_retcode = PAM_SUCCESS;
@@ -141,6 +127,36 @@ static int pamconv(int num_msg, const struct pam_message **msg,
                         default:
                                 free(reply);
                                 return PAM_CONV_ERR;
+                        }
+                } else {
+                        /*
+                         * stdio is connected, so interact directly
+                         */
+                        switch(PAM_MSG_MEMBER(msg, count, msg_style)) {
+                        case PAM_PROMPT_ECHO_ON:
+                                fputs(PAM_MSG_MEMBER(msg, count, msg), stderr);
+                                fgets(buf, sizeof(buf), stdin);
+                                reply[count].resp = xstrdup(buf);
+                                reply[count].resp_retcode = PAM_SUCCESS;
+                                break;
+                        case PAM_PROMPT_ECHO_OFF:
+                                reply[count].resp = xstrdup(
+                                    read_passphrase(PAM_MSG_MEMBER(msg, count, 
+                                    msg), 1));
+                                reply[count].resp_retcode = PAM_SUCCESS;
+                                break;
+                        case PAM_ERROR_MSG:
+                        case PAM_TEXT_INFO:
+                                if ((*msg)[count].msg != NULL)
+                                        fprintf(stderr, "%s\n", 
+                                            PAM_MSG_MEMBER(msg, count, msg));
+                                reply[count].resp = xstrdup("");
+                                reply[count].resp_retcode = PAM_SUCCESS;
+                                break;
+                        default:
+                                free(reply);
+                                return PAM_CONV_ERR;
+                        }
                 }
         }
 
@@ -154,25 +170,21 @@ void pam_cleanup_proc(void *context)
 {
         int pam_retval;
 
-        if (pamh != NULL)
-        {
+        if (pamh) {
                 pam_retval = pam_close_session(pamh, 0);
-                if (pam_retval != PAM_SUCCESS) {
+                if (pam_retval != PAM_SUCCESS)
                         log("Cannot close PAM session[%d]: %.200s",
-                                pam_retval, PAM_STRERROR(pamh, pam_retval));
-                }
+                            pam_retval, PAM_STRERROR(pamh, pam_retval));
 
                 pam_retval = pam_setcred(pamh, PAM_DELETE_CRED);
-                if (pam_retval != PAM_SUCCESS) {
-                        debug("Cannot delete credentials[%d]: %.200s",
-                                pam_retval, PAM_STRERROR(pamh, pam_retval));
-                }
+                if (pam_retval != PAM_SUCCESS)
+                        debug("Cannot delete credentials[%d]: %.200s", 
+                            pam_retval, PAM_STRERROR(pamh, pam_retval));
 
                 pam_retval = pam_end(pamh, pam_retval);
-                if (pam_retval != PAM_SUCCESS) {
+                if (pam_retval != PAM_SUCCESS)
                         log("Cannot release PAM authentication[%d]: %.200s",
-                                pam_retval, PAM_STRERROR(pamh, pam_retval));
-                }
+                            pam_retval, PAM_STRERROR(pamh, pam_retval));
         }
 }
 
@@ -197,12 +209,13 @@ int auth_pam_password(struct passwd *pw, const char *password)
         pamstate = INITIAL_LOGIN;
         pam_retval = do_pam_authenticate(0);
         if (pam_retval == PAM_SUCCESS) {
-                debug("PAM Password authentication accepted for user \"%.100s\"",
-                        pw->pw_name);
+                debug("PAM Password authentication accepted for "
+                    "user \"%.100s\"", pw->pw_name);
                 return 1;
         } else {
-                debug("PAM Password authentication for \"%.100s\" failed[%d]: %s",
-                        pw->pw_name, pam_retval, PAM_STRERROR(pamh, pam_retval));
+                debug("PAM Password authentication for \"%.100s\" "
+                    "failed[%d]: %s", pw->pw_name, pam_retval, 
+                    PAM_STRERROR(pamh, pam_retval));
                 return 0;
         }
 }
@@ -213,22 +226,21 @@ int do_pam_account(char *username, char *remote_user)
         int pam_retval;
         extern ServerOptions options;
 
+        pam_set_conv(&conv);
+
         debug("PAM setting rhost to \"%.200s\"",
             get_canonical_hostname(options.reverse_mapping_check));
         pam_retval = pam_set_item(pamh, PAM_RHOST,
                 get_canonical_hostname(options.reverse_mapping_check));
-        if (pam_retval != PAM_SUCCESS) {
-                fatal("PAM set rhost failed[%d]: %.200s",
-                        pam_retval, PAM_STRERROR(pamh, pam_retval));
-        }
-
-        if (remote_user != NULL) {
+        if (pam_retval != PAM_SUCCESS)
+                fatal("PAM set rhost failed[%d]: %.200s", pam_retval,
+                    PAM_STRERROR(pamh, pam_retval));
+        if (remote_user) {
                 debug("PAM setting ruser to \"%.200s\"", remote_user);
                 pam_retval = pam_set_item(pamh, PAM_RUSER, remote_user);
-                if (pam_retval != PAM_SUCCESS) {
-                        fatal("PAM set ruser failed[%d]: %.200s",
-                                pam_retval, PAM_STRERROR(pamh, pam_retval));
-                }
+                if (pam_retval != PAM_SUCCESS)
+                        fatal("PAM set ruser failed[%d]: %.200s", pam_retval, 
+                            PAM_STRERROR(pamh, pam_retval));
         }
 
         pam_retval = pam_acct_mgmt(pamh, 0);
@@ -237,13 +249,14 @@ int do_pam_account(char *username, char *remote_user)
                         /* This is what we want */
                         break;
                 case PAM_NEW_AUTHTOK_REQD:
-                        pam_msg_cat(NEW_AUTHTOK_MSG);
+                        message_cat(&pam_msg, NEW_AUTHTOK_MSG);
                         /* flag that password change is necessary */
                         password_change_required = 1;
                         break;
                 default:
-                        log("PAM rejected by account configuration[%d]: %.200s",
-                                pam_retval, PAM_STRERROR(pamh, pam_retval));
+                        log("PAM rejected by account configuration[%d]: "
+                            "%.200s", pam_retval, PAM_STRERROR(pamh, 
+                            pam_retval));
                         return(0);
         }
 
@@ -258,17 +271,15 @@ void do_pam_session(char *username, const char *ttyname)
         if (ttyname != NULL) {
                 debug("PAM setting tty to \"%.200s\"", ttyname);
                 pam_retval = pam_set_item(pamh, PAM_TTY, ttyname);
-                if (pam_retval != PAM_SUCCESS) {
+                if (pam_retval != PAM_SUCCESS)
                         fatal("PAM set tty failed[%d]: %.200s",
-                                pam_retval, PAM_STRERROR(pamh, pam_retval));
-                }
+                            pam_retval, PAM_STRERROR(pamh, pam_retval));
         }
 
         pam_retval = pam_open_session(pamh, 0);
-        if (pam_retval != PAM_SUCCESS) {
+        if (pam_retval != PAM_SUCCESS)
                 fatal("PAM session setup failed[%d]: %.200s",
-                        pam_retval, PAM_STRERROR(pamh, pam_retval));
-        }
+                    pam_retval, PAM_STRERROR(pamh, pam_retval));
 }
 
 /* Set PAM credentials */
@@ -279,13 +290,12 @@ void do_pam_setcred(void)
         debug("PAM establishing creds");
         pam_retval = pam_setcred(pamh, PAM_ESTABLISH_CRED);
         if (pam_retval != PAM_SUCCESS) {
-                if(was_authenticated) {
+                if (was_authenticated)
                         fatal("PAM setcred failed[%d]: %.200s",
-                                pam_retval, PAM_STRERROR(pamh, pam_retval));
-                } else {
+                            pam_retval, PAM_STRERROR(pamh, pam_retval));
+                else
                         debug("PAM setcred failed[%d]: %.200s",
-                                pam_retval, PAM_STRERROR(pamh, pam_retval));
-                }
+                            pam_retval, PAM_STRERROR(pamh, pam_retval));
         }
 }
 
@@ -307,15 +317,13 @@ void do_pam_chauthtok(void)
 
         if (password_change_required) {
                 pamstate = OTHER;
-                /*
-                 * XXX: should we really loop forever?
-                 */
+                /* XXX: should we really loop forever? */
                 do {
-                        pam_retval = pam_chauthtok(pamh, PAM_CHANGE_EXPIRED_AUTHTOK);
-                        if (pam_retval != PAM_SUCCESS) {
+                        pam_retval = pam_chauthtok(pamh, 
+                            PAM_CHANGE_EXPIRED_AUTHTOK);
+                        if (pam_retval != PAM_SUCCESS)
                                 log("PAM pam_chauthtok failed[%d]: %.200s",
-                                        pam_retval, PAM_STRERROR(pamh, pam_retval));
-                        }
+                                    pam_retval, PAM_STRERROR(pamh, pam_retval));
                 } while (pam_retval != PAM_SUCCESS);
         }
 }
@@ -336,11 +344,9 @@ void start_pam(const char *user)
 
         pam_retval = pam_start(SSHD_PAM_SERVICE, user, &conv, &pamh);
 
-        if (pam_retval != PAM_SUCCESS) {
+        if (pam_retval != PAM_SUCCESS)
                 fatal("PAM initialisation failed[%d]: %.200s",
-                        pam_retval, PAM_STRERROR(pamh, pam_retval));
-        }
-
+                    pam_retval, PAM_STRERROR(pamh, pam_retval));
 #ifdef PAM_TTY_KLUDGE
         /*
          * Some PAM modules (e.g. pam_time) require a TTY to operate,
@@ -350,10 +356,9 @@ void start_pam(const char *user)
          * Kludge: Set a fake PAM_TTY
          */
         pam_retval = pam_set_item(pamh, PAM_TTY, "ssh");
-        if (pam_retval != PAM_SUCCESS) {
+        if (pam_retval != PAM_SUCCESS)
                 fatal("PAM set tty failed[%d]: %.200s",
-                        pam_retval, PAM_STRERROR(pamh, pam_retval));
-        }
+                    pam_retval, PAM_STRERROR(pamh, pam_retval));
 #endif /* PAM_TTY_KLUDGE */
 
         fatal_add_cleanup(&pam_cleanup_proc, NULL);
@@ -377,26 +382,25 @@ void print_pam_messages(void)
                 fputs(pam_msg, stderr);
 }
 
-/* Append a message to the PAM message buffer */
-void pam_msg_cat(const char *msg)
+/* Append a message to buffer */
+void message_cat(char **p, const char *a)
 {
-        char *p;
-        size_t new_msg_len;
-        size_t pam_msg_len;
+        char *cp;
+        size_t new_len;
 
-        new_msg_len = strlen(msg);
+        new_len = strlen(a);
 
-        if (pam_msg) {
-                pam_msg_len = strlen(pam_msg);
-                pam_msg = xrealloc(pam_msg, new_msg_len + pam_msg_len + 2);
-                p = pam_msg + pam_msg_len;
-        } else {
-                pam_msg = p = xmalloc(new_msg_len + 2);
-        }
+        if (*p) {
+                size_t len = strlen(*p);
+
+                *p = xrealloc(*p, new_len + len + 2);
+                cp = *p + len;
+        } else
+                *p = cp = xmalloc(new_len + 2);
 
-        memcpy(p, msg, new_msg_len);
-        p[new_msg_len] = '\n';
-        p[new_msg_len + 1] = '\0';
+        memcpy(cp, a, new_len);
+        cp[new_len] = '\n';
+        cp[new_len + 1] = '\0';
 }
 
 #endif /* USE_PAM */