Modify the authentication API such that the init and cleanup functions

are always called, regardless of whether or not we are going to
verify a password.  This is needed for proper PAM session support.

plugins/sudoers/auth/API

@@ -12,7 +12,7 @@ typedef struct sudo_auth {
     char *name;			/* name of the method in string form */
     void *data;                 /* method-specific data pointer */
 
-    int (*init)(struct passwd *pw, char **prompt, sudo_auth *auth);
+    int (*init)(struct passwd *pw, sudo_auth *auth);
     int (*setup)(struct passwd *pw, char **prompt, sudo_auth *auth);
     int (*verify)(struct passwd *pw, char *p, sudo_auth *auth);
     int (*cleanup)(struct passwd *pw, sudo_auth *auth);
@@ -64,11 +64,10 @@ The member functions can return the following values:
 
 The functions in the struct are as follows:
 
-    int init(struct passwd *pw, char **prompt, sudo_auth *auth)
+    int init(struct passwd *pw, sudo_auth *auth)
         Function to do any one-time initialization for the auth
         method.  All of the "init" functions are run before anything
-        else.  A pointer to the prompt string may be used to add
-        method-specific info to the prompt.
+        else.
 
     int setup(struct passwd *pw, char **prompt, sudo_auth *auth)
         Function to do method-specific setup.  All the "setup"

plugins/sudoers/auth/bsdauth.c

@@ -54,7 +54,7 @@
 extern char *login_style;		/* from sudo.c */
 
 int
-bsdauth_init(struct passwd *pw, char **promptp, sudo_auth *auth)
+bsdauth_init(struct passwd *pw, sudo_auth *auth)
 {
     static auth_session_t *as;
     extern login_cap_t *lc;			/* from sudo.c */

plugins/sudoers/auth/fwtk.c

@@ -50,7 +50,7 @@
 #include "sudo_auth.h"
 
 int
-fwtk_init(struct passwd *pw, char **promptp, sudo_auth *auth)
+fwtk_init(struct passwd *pw, sudo_auth *auth)
 {
     static Cfg *confp;			/* Configuration entry struct */
     char resp[128];			/* Response from the server */

plugins/sudoers/auth/kerb4.c

@@ -48,7 +48,7 @@
 #include "sudo_auth.h"
 
 int
-kerb4_init(struct passwd *pw, char **promptp, sudo_auth *auth)
+kerb4_init(struct passwd *pw, sudo_auth *auth)
 {
     static char realm[REALM_SZ];
 

plugins/sudoers/auth/kerb5.c

@@ -88,14 +88,49 @@ krb5_get_init_creds_opt_free(krb5_get_init_creds_opt *opts)
 #endif
 
 int
-kerb5_init(struct passwd *pw, char **promptp, sudo_auth *auth)
+kerb5_setup(struct passwd *pw, char **promptp, sudo_auth *auth)
+{
+    static char	*krb5_prompt;
+
+    if (krb5_prompt == NULL) {
+	krb5_context	sudo_context;
+	krb5_principal	princ;
+	char		*pname;
+	krb5_error_code	error;
+
+	sudo_context = ((sudo_krb5_datap) auth->data)->sudo_context;
+	princ = ((sudo_krb5_datap) auth->data)->princ;
+
+	/*
+	 * Really, we need to tell the caller not to prompt for password. The
+	 * API does not currently provide this unless the auth is standalone.
+	 */
+	if ((error = krb5_unparse_name(sudo_context, princ, &pname))) {
+	    log_error(NO_EXIT|NO_MAIL,
+		      _("%s: unable to unparse princ ('%s'): %s"), auth->name,
+		      pw->pw_name, error_message(error));
+	    return AUTH_FAILURE;
+	}
+
+	/* Only rewrite prompt if user didn't specify their own. */
+	/*if (!strcmp(prompt, PASSPROMPT)) { */
+	    easprintf(&krb5_prompt, "Password for %s: ", pname);
+	/*}*/
+	free(pname);
+    }
+    *promptp = krb5_prompt;
+
+    return AUTH_SUCCESS;
+}
+
+int
+kerb5_init(struct passwd *pw, sudo_auth *auth)
 {
     krb5_context	sudo_context;
     krb5_ccache		ccache;
     krb5_principal	princ;
     krb5_error_code 	error;
     char		cache_name[64];
-    char		*pname;
 
     auth->data = (void *) &sudo_krb5_data; /* Stash all our data here */
 
@@ -117,25 +152,6 @@ kerb5_init(struct passwd *pw, char **promptp, sudo_auth *auth)
     }
     princ = sudo_krb5_data.princ;
 
-    /*
-     * Really, we need to tell the caller not to prompt for password.
-     * The API does not currently provide this unless the auth is standalone.
-     */
-#if 1
-    if ((error = krb5_unparse_name(sudo_context, princ, &pname))) {
-	log_error(NO_EXIT|NO_MAIL,
-		  _("%s: unable to unparse princ ('%s'): %s"), auth->name,
-		  pw->pw_name, error_message(error));
-	return AUTH_FAILURE;
-    }
-
-    /* Only rewrite prompt if user didn't specify their own. */
-    /*if (!strcmp(prompt, PASSPROMPT)) { */
-	easprintf(promptp, "Password for %s: ", pname);
-    /*}*/
-    free(pname);
-#endif
-
     (void) snprintf(cache_name, sizeof(cache_name), "MEMORY:sudocc_%ld",
 		    (long) getpid());
     if ((error = krb5_cc_resolve(sudo_context, cache_name,

plugins/sudoers/auth/pam.c

@@ -80,7 +80,7 @@ static int gotintr;
 static pam_handle_t *pamh;
 
 int
-pam_init(struct passwd *pw, char **promptp, sudo_auth *auth)
+pam_init(struct passwd *pw, sudo_auth *auth)
 {
     static struct pam_conv pam_conv;
     static int pam_status;
@@ -184,10 +184,11 @@ pam_cleanup(struct passwd *pw, sudo_auth *auth)
     int *pam_status = (int *) auth->data;
 
     /* If successful, we can't close the session until pam_end_session() */
-    if (auth->status == AUTH_SUCCESS)
+    if (*pam_status == AUTH_SUCCESS)
 	return AUTH_SUCCESS;
 
     *pam_status = pam_end(pamh, *pam_status | PAM_DATA_SILENT);
+    pamh = NULL;
     return *pam_status == PAM_SUCCESS ? AUTH_SUCCESS : AUTH_FAILURE;
 }
 
@@ -209,10 +210,6 @@ pam_begin_session(struct passwd *pw, sudo_auth *auth)
 	goto done;
     }
 
-    /* If the user did not have to authenticate there is no pam handle yet. */
-    if (pamh == NULL)
-	pam_init(pw, NULL, NULL);
-
     /*
      * Update PAM_USER to reference the user we are running the command
      * as, as opposed to the user we authenticated as.
@@ -246,22 +243,19 @@ pam_end_session(struct passwd *pw, sudo_auth *auth)
 {
     int status = PAM_SUCCESS;
 
+    if (pamh != NULL) {
 #ifndef NO_PAM_SESSION
-    /* If the user did not have to authenticate there is no pam handle yet. */
-    if (pamh == NULL)
-	pam_init(pw, NULL, NULL);
-
 	/*
 	 * Update PAM_USER to reference the user we are running the command
 	 * as to match the call to pam_open_session().
 	 */
 	(void) pam_set_item(pamh, PAM_USER, pw->pw_name);
-
 	(void) pam_close_session(pamh, PAM_SILENT);
 #endif
-
-    if (pamh != NULL)
 	status = pam_end(pamh, PAM_SUCCESS | PAM_DATA_SILENT);
+	pamh = NULL;
+    }
+
     return status == PAM_SUCCESS ? AUTH_SUCCESS : AUTH_FAILURE;
 }
 

plugins/sudoers/auth/passwd.c

@@ -49,7 +49,7 @@
 #define HAS_AGEINFO(p, l)	(l == 18 && p[DESLEN] == ',')
 
 int
-passwd_init(struct passwd *pw, char **promptp, sudo_auth *auth)
+passwd_init(struct passwd *pw, sudo_auth *auth)
 {
 #ifdef HAVE_SKEYACCESS
     if (skeyaccess(pw, user_tty, NULL, NULL) == 0)

plugins/sudoers/auth/secureware.c

@@ -53,7 +53,7 @@
 #include "sudo_auth.h"
 
 int
-secureware_init(struct passwd *pw, char **promptp, sudo_auth *auth)
+secureware_init(struct passwd *pw, sudo_auth *auth)
 {
 #ifdef __alpha
     extern int crypt_type;

plugins/sudoers/auth/securid.c

@@ -56,7 +56,7 @@
 union config_record configure;
 
 int
-securid_init(struct passwd *pw, char **promptp, sudo_auth *auth)
+securid_init(struct passwd *pw, sudo_auth *auth)
 {
     static struct SD_CLIENT sd_dat;		/* SecurID data block */
 

plugins/sudoers/auth/securid5.c

@@ -59,7 +59,6 @@
  * securid_init - Initialises communications with ACE server
  * Arguments in:
  *     pw - UNUSED
- *     promptp - UNUSED
  *     auth - sudo authentication structure
  *
  * Results out:
@@ -68,7 +67,7 @@
  *                   success.
  */
 int
-securid_init(struct passwd *pw, char **promptp, sudo_auth *auth)
+securid_init(struct passwd *pw, sudo_auth *auth)
 {
     static SDI_HANDLE sd_dat;			/* SecurID handle */
 

plugins/sudoers/auth/sudo_auth.c

@@ -86,7 +86,7 @@ static sudo_auth auth_switch[] = {
     AUTH_ENTRY("kerb4", 0, kerb4_init, NULL, kerb4_verify, NULL, NULL, NULL)
 #endif
 #ifdef HAVE_KERB5
-    AUTH_ENTRY("kerb5", 0, kerb5_init, NULL, kerb5_verify, kerb5_cleanup, NULL, NULL)
+    AUTH_ENTRY("kerb5", 0, kerb5_init, kerb5_setup, kerb5_verify, kerb5_cleanup, NULL, NULL)
 #endif
 #ifdef HAVE_SKEY
     AUTH_ENTRY("S/Key", 0, NULL, rfc1938_setup, rfc1938_verify, NULL, NULL, NULL)
@@ -97,35 +97,19 @@ static sudo_auth auth_switch[] = {
     AUTH_ENTRY(NULL, 0, NULL, NULL, NULL, NULL, NULL, NULL)
 };
 
+static int standalone;
+
 extern char **NewArgv; /* XXX - for auditing */
 
 static void pass_warn(void);
 
 int
-verify_user(struct passwd *pw, char *prompt)
+sudo_auth_init(struct passwd *pw)
 {
-    int counter = def_passwd_tries + 1;
-    int success = AUTH_FAILURE;
-    int flags, status, standalone, rval;
-    char *p;
     sudo_auth *auth;
-    sigaction_t sa, osa;
 
-    /* Enable suspend during password entry. */
-    sigemptyset(&sa.sa_mask);
-    sa.sa_flags = SA_RESTART;
-    sa.sa_handler = SIG_DFL;
-    (void) sigaction(SIGTSTP, &sa, &osa);
-
-    /* Make sure we have at least one auth method. */
-    if (auth_switch[0].name == NULL) {
-	audit_failure(NewArgv, "no authentication methods");
-    	log_error(0,
-	    _("There are no authentication methods compiled into sudo!  "
-	    "If you want to turn off authentication, use the "
-	    "--disable-authentication configure option."));
-	return -1;
-    }
+    if (auth_switch[0].name == NULL)
+	return AUTH_SUCCESS;
 
     /* Make sure we haven't mixed standalone and shared auth methods. */
     standalone = IS_STANDALONE(&auth_switch[0]);
@@ -146,10 +130,12 @@ verify_user(struct passwd *pw, char *prompt)
 	    if (NEEDS_USER(auth))
 		set_perms(PERM_USER);
 
-	    status = (auth->init)(pw, &prompt, auth);
-	    if (status == AUTH_FAILURE)
+	    switch ((auth->init)(pw, auth)) {
+		case AUTH_FAILURE:
 		    SET(auth->flags, FLAG_DISABLED);
-	    else if (status == AUTH_FATAL) {	/* XXX log */
+		    break;
+		case AUTH_FATAL:
+		    /* XXX log */
 		    audit_failure(NewArgv, "authentication failure");
 		    return -1;		/* assume error msg already printed */
 	    }
@@ -158,6 +144,59 @@ verify_user(struct passwd *pw, char *prompt)
 		restore_perms();
 	}
     }
+    return AUTH_SUCCESS;
+}
+
+int
+sudo_auth_cleanup(struct passwd *pw)
+{
+    sudo_auth *auth;
+
+    /* Call cleanup routines. */
+    for (auth = auth_switch; auth->name; auth++) {
+	if (auth->cleanup && !IS_DISABLED(auth)) {
+	    if (NEEDS_USER(auth))
+		set_perms(PERM_USER);
+
+	    if ((auth->cleanup)(pw, auth) == AUTH_FATAL) {
+		/* XXX log */
+		audit_failure(NewArgv, "authentication failure");
+		return -1;		/* assume error msg already printed */
+	    }
+
+	    if (NEEDS_USER(auth))
+		restore_perms();
+	}
+    }
+    return AUTH_SUCCESS;
+}
+
+int
+verify_user(struct passwd *pw, char *prompt)
+{
+    int counter = def_passwd_tries + 1;
+    int success = AUTH_FAILURE;
+    int flags, status, rval;
+    char *p;
+    sudo_auth *auth;
+    sigaction_t sa, osa;
+
+    /* Enable suspend during password entry. */
+    sigemptyset(&sa.sa_mask);
+    sa.sa_flags = SA_RESTART;
+    sa.sa_handler = SIG_DFL;
+    (void) sigaction(SIGTSTP, &sa, &osa);
+
+    /* Make sure we have at least one auth method. */
+    /* XXX - check FLAG_DISABLED too */
+    if (auth_switch[0].name == NULL) {
+	audit_failure(NewArgv, "no authentication methods");
+    	log_error(0,
+	    _("There are no authentication methods compiled into sudo!  "
+	    "If you want to turn off authentication, use the "
+	    "--disable-authentication configure option."));
+	return -1;
+    }
 
     while (--counter) {
 	/* Do any per-method setup and unconfigure the method if needed */
@@ -203,31 +242,14 @@ verify_user(struct passwd *pw, char *prompt)
 		restore_perms();
 
 	    if (auth->status != AUTH_FAILURE)
-		goto cleanup;
+		goto done;
 	}
 	if (!standalone)
 	    zero_bytes(p, strlen(p));
 	pass_warn();
     }
 
-cleanup:
-    /* Call cleanup routines. */
-    for (auth = auth_switch; auth->name; auth++) {
-	if (auth->cleanup && !IS_DISABLED(auth)) {
-	    if (NEEDS_USER(auth))
-		set_perms(PERM_USER);
-
-	    status = (auth->cleanup)(pw, auth);
-	    if (status == AUTH_FATAL) {	/* XXX log */
-		audit_failure(NewArgv, "authentication failure");
-		return -1;		/* assume error msg already printed */
-	    }
-
-	    if (NEEDS_USER(auth))
-		restore_perms();
-	}
-    }
-
+done:
     switch (success) {
 	case AUTH_SUCCESS:
 	    (void) sigaction(SIGTSTP, &osa, NULL);
@@ -257,7 +279,8 @@ cleanup:
     return rval;
 }
 
-int auth_begin_session(struct passwd *pw)
+int
+sudo_auth_begin_session(struct passwd *pw)
 {
     sudo_auth *auth;
     int status;
@@ -274,7 +297,8 @@ int auth_begin_session(struct passwd *pw)
     return TRUE;
 }
 
-int auth_end_session(struct passwd *pw)
+int
+sudo_auth_end_session(struct passwd *pw)
 {
     sudo_auth *auth;
     int status;

plugins/sudoers/auth/sudo_auth.h

@@ -28,7 +28,7 @@ typedef struct sudo_auth {
     int status;			/* status from verify routine */
     char *name;			/* name of the method as a string */
     void *data;			/* method-specific data pointer */
-    int (*init)(struct passwd *pw, char **prompt, struct sudo_auth *auth);
+    int (*init)(struct passwd *pw, struct sudo_auth *auth);
     int (*setup)(struct passwd *pw, char **prompt, struct sudo_auth *auth);
     int (*verify)(struct passwd *pw, char *p, struct sudo_auth *auth);
     int (*cleanup)(struct passwd *pw, struct sudo_auth *auth);
@@ -55,10 +55,10 @@ char *auth_getpass(const char *prompt, int timeout, int type);
 extern sudo_conv_t sudo_conv;
 
 /* Prototypes for standalone methods */
-int fwtk_init(struct passwd *pw, char **prompt, sudo_auth *auth);
+int fwtk_init(struct passwd *pw, sudo_auth *auth);
 int fwtk_verify(struct passwd *pw, char *prompt, sudo_auth *auth);
 int fwtk_cleanup(struct passwd *pw, sudo_auth *auth);
-int pam_init(struct passwd *pw, char **prompt, sudo_auth *auth);
+int pam_init(struct passwd *pw, sudo_auth *auth);
 int pam_verify(struct passwd *pw, char *prompt, sudo_auth *auth);
 int pam_cleanup(struct passwd *pw, sudo_auth *auth);
 int pam_begin_session(struct passwd *pw, sudo_auth *auth);
@@ -68,27 +68,28 @@ int sia_verify(struct passwd *pw, char *prompt, sudo_auth *auth);
 int sia_cleanup(struct passwd *pw, sudo_auth *auth);
 int aixauth_verify(struct passwd *pw, char *pass, sudo_auth *auth);
 int aixauth_cleanup(struct passwd *pw, sudo_auth *auth);
-int bsdauth_init(struct passwd *pw, char **prompt, sudo_auth *auth);
+int bsdauth_init(struct passwd *pw, sudo_auth *auth);
 int bsdauth_verify(struct passwd *pw, char *prompt, sudo_auth *auth);
 int bsdauth_cleanup(struct passwd *pw, sudo_auth *auth);
 
 /* Prototypes for normal methods */
-int passwd_init(struct passwd *pw, char **prompt, sudo_auth *auth);
+int passwd_init(struct passwd *pw, sudo_auth *auth);
 int passwd_verify(struct passwd *pw, char *pass, sudo_auth *auth);
 int passwd_cleanup(struct passwd *pw, sudo_auth *auth);
-int secureware_init(struct passwd *pw, char **prompt, sudo_auth *auth);
+int secureware_init(struct passwd *pw, sudo_auth *auth);
 int secureware_verify(struct passwd *pw, char *pass, sudo_auth *auth);
 int secureware_cleanup(struct passwd *pw, sudo_auth *auth);
 int rfc1938_setup(struct passwd *pw, char **prompt, sudo_auth *auth);
 int rfc1938_verify(struct passwd *pw, char *pass, sudo_auth *auth);
 int afs_verify(struct passwd *pw, char *pass, sudo_auth *auth);
 int dce_verify(struct passwd *pw, char *pass, sudo_auth *auth);
-int kerb4_init(struct passwd *pw, char **prompt, sudo_auth *auth);
+int kerb4_init(struct passwd *pw, sudo_auth *auth);
 int kerb4_verify(struct passwd *pw, char *pass, sudo_auth *auth);
-int kerb5_init(struct passwd *pw, char **prompt, sudo_auth *auth);
+int kerb5_init(struct passwd *pw, sudo_auth *auth);
+int kerb5_setup(struct passwd *pw, char **prompt, sudo_auth *auth);
 int kerb5_verify(struct passwd *pw, char *pass, sudo_auth *auth);
 int kerb5_cleanup(struct passwd *pw, sudo_auth *auth);
-int securid_init(struct passwd *pw, char **prompt, sudo_auth *auth);
+int securid_init(struct passwd *pw, sudo_auth *auth);
 int securid_setup(struct passwd *pw, char **prompt, sudo_auth *auth);
 int securid_verify(struct passwd *pw, char *pass, sudo_auth *auth);
 

plugins/sudoers/check.c

@@ -98,6 +98,7 @@ static struct passwd *get_authpw(void);
 int
 check_user(int validated, int mode)
 {
+    struct passwd *auth_pw;
     char *timestampdir = NULL;
     char *timestampfile = NULL;
     char *prompt;
@@ -113,6 +114,11 @@ check_user(int validated, int mode)
 	    ctim_get(&sb, &tty_info.ctime);
     }
 
+    /* Init authentication system regardless of whether we need a password. */
+    auth_pw = get_authpw();
+    sudo_auth_init(auth_pw);
+    pw_delref(auth_pw);
+
     /* Always prompt for a password when -k was specified with the command. */
     if (ISSET(mode, MODE_IGNORE_TICKET)) {
 	SET(validated, FLAG_CHECK_USER);
@@ -124,11 +130,13 @@ check_user(int validated, int mode)
 	if (user_uid == 0 || (user_uid == runas_pw->pw_uid &&
 	    (!runas_gr || user_in_group(sudo_user.pw, runas_gr->gr_name))) ||
 	    user_is_exempt())
-	    return TRUE;
+	    goto done;
     }
 
-    if (build_timestamp(&timestampdir, &timestampfile) == -1)
-	return -1;
+    if (build_timestamp(&timestampdir, &timestampfile) == -1) {
+	rval = -1;
+	goto done;
+    }
 
     status = timestamp_status(timestampdir, timestampfile, user_name,
 	TS_MAKE_DIRS);
@@ -139,7 +147,8 @@ check_user(int validated, int mode)
 	/* Bail out if we are non-interactive and a password is required */
 	if (ISSET(mode, MODE_NONINTERACTIVE)) {
 	    warningx(_("sorry, a password is required to run %s"), getprogname());
-	    return -1;
+	    rval = -1;
+	    goto done;
 	}
 
 	/* XXX - should not lecture if askpass helper is being used. */
@@ -160,6 +169,9 @@ check_user(int validated, int mode)
     efree(timestampdir);
     efree(timestampfile);
 
+done:
+    sudo_auth_cleanup(auth_pw);
+
     return rval;
 }
 

plugins/sudoers/sudoers.c

@@ -254,7 +254,7 @@ sudoers_policy_close(int exit_status, int error_code)
 
     /* Close the session we opened in sudoers_policy_init_session(). */
     if (ISSET(sudo_mode, MODE_RUN|MODE_EDIT))
-	(void)auth_end_session(runas_pw);
+	(void)sudo_auth_end_session(runas_pw);
 
     /* Free remaining references to password and group entries. */
     pw_delref(sudo_user.pw);
@@ -277,7 +277,7 @@ sudoers_policy_init_session(struct passwd *pwd)
 	return -1;
     }
 
-    return auth_begin_session(pwd);
+    return sudo_auth_begin_session(pwd);
 }
 
 static int

plugins/sudoers/sudoers.h

@@ -218,8 +218,10 @@ int user_is_exempt(void);
 
 /* sudo_auth.c */
 int verify_user(struct passwd *, char *);
-int auth_begin_session(struct passwd *);
-int auth_end_session();
+int sudo_auth_begin_session(struct passwd *);
+int sudo_auth_end_session(struct passwd *);
+int sudo_auth_init(struct passwd *pw);
+int sudo_auth_cleanup(struct passwd *pw);
 
 /* parse.c */
 int sudo_file_open(struct sudo_nss *);