From dfc90ff0b1de9c848fe5b5af694c6feea2717091 Mon Sep 17 00:00:00 2001
From: "Todd C. Miller" <Todd.Miller@courtesan.com>
Date: Wed, 11 Apr 2012 19:51:56 -0400
Subject: [PATCH] Instead of treating ^C from tgetpass() specially, always
 return AUTH_INTR if tgetpass() returned NULL. Treat PAM_AUTHINFO_UNAVAIL like
 PAM_AUTH_ERR which Mac OS X returns this when there is no tty.

---
 plugins/sudoers/auth/pam.c | 51 +++++++++++++++++++++-----------------
 1 file changed, 28 insertions(+), 23 deletions(-)

diff --git a/plugins/sudoers/auth/pam.c b/plugins/sudoers/auth/pam.c
index 64ac30a80..0de9af212 100644
--- a/plugins/sudoers/auth/pam.c
+++ b/plugins/sudoers/auth/pam.c
@@ -71,7 +71,7 @@
 static int converse(int, PAM_CONST struct pam_message **,
 		    struct pam_response **, void *);
 static char *def_prompt = "Password:";
-static int gotintr;
+static int getpass_error;
 
 #ifndef PAM_DATA_SILENT
 #define PAM_DATA_SILENT	0
@@ -166,10 +166,12 @@ sudo_pam_verify(struct passwd *pw, char *prompt, sudo_auth *auth)
 	    }
 	    /* FALLTHROUGH */
 	case PAM_AUTH_ERR:
-	    if (gotintr) {
+	case PAM_AUTHINFO_UNAVAIL:
+	    if (getpass_error) {
 		/* error or ^C from tgetpass() */
 		debug_return_int(AUTH_INTR);
 	    }
+	    /* FALLTHROUGH */
 	case PAM_MAXTRIES:
 	case PAM_PERM_DENIED:
 	    debug_return_int(AUTH_FAILURE);
@@ -297,6 +299,7 @@ converse(int num_msg, PAM_CONST struct pam_message **msg,
     const char *prompt;
     char *pass;
     int n, type, std_prompt;
+    int ret = PAM_AUTH_ERR;
     debug_decl(converse, SUDO_DEBUG_AUTH)
 
     if ((*response = malloc(num_msg * sizeof(struct pam_response))) == NULL)
@@ -308,12 +311,13 @@ converse(int num_msg, PAM_CONST struct pam_message **msg,
 	switch (pm->msg_style) {
 	    case PAM_PROMPT_ECHO_ON:
 		type = SUDO_CONV_PROMPT_ECHO_ON;
+		/* FALLTHROUGH */
 	    case PAM_PROMPT_ECHO_OFF:
 		prompt = def_prompt;
 
 		/* Error out if the last password read was interrupted. */
-		if (gotintr)
-		    goto err;
+		if (getpass_error)
+		    goto done;
 
 		/* Is the sudo prompt standard? (If so, we'l just use PAM's) */
 		std_prompt =  strncmp(def_prompt, "Password:", 9) == 0 &&
@@ -335,13 +339,12 @@ converse(int num_msg, PAM_CONST struct pam_message **msg,
 		/* Read the password unless interrupted. */
 		pass = auth_getpass(prompt, def_passwd_timeout * 60, type);
 		if (pass == NULL) {
-		    /* We got ^C instead of a password; abort quickly. */
-		    if (errno == EINTR)
-			gotintr = 1;
-#if defined(__darwin__) || defined(__APPLE__)
+		    /* Error (or ^C) reading password, don't try again. */
+		    getpass_error = 1;
+#if (defined(__darwin__) || defined(__APPLE__)) && !defined(OPENPAM_VERSION)
 		    pass = "";
 #else
-		    goto err;
+		    goto done;
 #endif
 		}
 		pr->resp = estrdup(pass);
@@ -358,23 +361,25 @@ converse(int num_msg, PAM_CONST struct pam_message **msg,
 		}
 		break;
 	    default:
-		goto err;
+		ret = PAM_CONV_ERR;
+		goto done;
 	}
     }
+    ret = PAM_SUCCESS;
 
-    debug_return_int(PAM_SUCCESS);
-
-err:
-    /* Zero and free allocated memory and return an error. */
-    for (pr = *response, n = num_msg; n--; pr++) {
-	if (pr->resp != NULL) {
-	    zero_bytes(pr->resp, strlen(pr->resp));
-	    free(pr->resp);
-	    pr->resp = NULL;
+done:
+    if (ret != PAM_SUCCESS) {
+	/* Zero and free allocated memory and return an error. */
+	for (pr = *response, n = num_msg; n--; pr++) {
+	    if (pr->resp != NULL) {
+		zero_bytes(pr->resp, strlen(pr->resp));
+		free(pr->resp);
+		pr->resp = NULL;
+	    }
 	}
+	zero_bytes(*response, num_msg * sizeof(struct pam_response));
+	free(*response);
+	*response = NULL;
     }
-    zero_bytes(*response, num_msg * sizeof(struct pam_response));
-    free(*response);
-    *response = NULL;
-    debug_return_int(gotintr ? PAM_AUTH_ERR : PAM_CONV_ERR);
+    debug_return_int(ret);
 }
-- 
2.50.0