Check auth_mkvalue(3) return value for NULL (malloc failure).

For constant strings we don't actually need to use auth_mkvalue(3).
Problem reported by Ross L Richardson.

4 files changed, 41 insertions, 20 deletions

diff --git a/libexec/login_passwd/login_passwd.c b/libexec/login_passwd/login_passwd.c
index 92790494489..df83a825d76 100644
--- a/libexec/login_passwd/login_passwd.c
+++ b/libexec/login_passwd/login_passwd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: login_passwd.c,v 1.18 2020/05/15 17:25:39 millert Exp $	*/
+/*	$OpenBSD: login_passwd.c,v 1.19 2021/01/02 20:32:20 millert Exp $	*/
 
 /*-
  * Copyright (c) 1995 Berkeley Software Design, Inc. All rights reserved.
@@ -49,7 +49,6 @@
 #include <util.h>
 
 #include <login_cap.h>
-#include <bsd_auth.h>
 
 int
 main(int argc, char *argv[])
@@ -121,7 +120,7 @@ main(int argc, char *argv[])
 	}
 	if (wheel != NULL && strcmp(wheel, "yes") != 0) {
 		fprintf(back, BI_VALUE " errormsg %s\n",
-		    auth_mkvalue("you are not in group wheel"));
+		    "you are not in group wheel");
 		fprintf(back, BI_REJECT "\n");
 		exit(1);
 	}
diff --git a/libexec/login_radius/login_radius.c b/libexec/login_radius/login_radius.c
index 9b00f973133..6e38ba7c138 100644
--- a/libexec/login_radius/login_radius.c
+++ b/libexec/login_radius/login_radius.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: login_radius.c,v 1.9 2017/04/27 20:55:52 millert Exp $	*/
+/*	$OpenBSD: login_radius.c,v 1.10 2021/01/02 20:32:20 millert Exp $	*/
 
 /*-
  * Copyright (c) 1996, 1997 Berkeley Software Design, Inc. All rights reserved.
@@ -183,19 +183,29 @@ main(int argc, char **argv)
 	    strcmp(service, "login") ? challenge : NULL, password, &emsg);
 
 	if (c == 0) {
-		if (*challenge == '\0')
+		if (*challenge == '\0') {
 			(void)fprintf(back, BI_AUTH "\n");
-		else {
-			(void)fprintf(back, BI_VALUE " challenge %s\n",
-			    auth_mkvalue(challenge));
-			(void)fprintf(back, BI_CHALLENGE "\n");
+			exit(0);
+		} else {
+			char *val = auth_mkvalue(challenge);
+			if (val != NULL) {
+				(void)fprintf(back, BI_VALUE " challenge %s\n",
+				    val);
+				(void)fprintf(back, BI_CHALLENGE "\n");
+				exit(0);
+			}
+			emsg = "unable to allocate memory";
+		}
+	}
+	if (emsg != NULL) {
+		if (strcmp(service, "login") == 0) {
+		    (void)fprintf(stderr, "%s\n", emsg);
+		} else {
+		    emsg = auth_mkvalue(emsg);
+		    (void)fprintf(back, BI_VALUE " errormsg %s\n",
+			emsg ? emsg : "unable to allocate memory");
 		}
-		exit(0);
 	}
-	if (emsg && strcmp(service, "login") == 0)
-		(void)fprintf(stderr, "%s\n", emsg);
-	else if (emsg)
-		(void)fprintf(back, "value errormsg %s\n", auth_mkvalue(emsg));
 	if (strcmp(service, "challenge") == 0) {
 		(void)fprintf(back, BI_SILENT "\n");
 		exit(0);
diff --git a/libexec/login_skey/login_skey.c b/libexec/login_skey/login_skey.c
index 11a3bae3503..f57f76ebc73 100644
--- a/libexec/login_skey/login_skey.c
+++ b/libexec/login_skey/login_skey.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: login_skey.c,v 1.28 2019/06/28 13:32:53 deraadt Exp $	*/
+/*	$OpenBSD: login_skey.c,v 1.29 2021/01/02 20:32:20 millert Exp $	*/
 
 /*
  * Copyright (c) 2000, 2001, 2004 Todd C. Miller <millert@openbsd.org>
@@ -157,8 +157,14 @@ main(int argc, char *argv[])
 	case MODE_CHALLENGE:
 		haskey = (skeychallenge2(fd, &skey, user, challenge) == 0);
 		strlcat(challenge, "\nS/Key Password:", sizeof(challenge));
-		fprintf(back, BI_VALUE " challenge %s\n",
-		    auth_mkvalue(challenge));
+		cp = auth_mkvalue(challenge);
+		if (cp == NULL) {
+			(void)fprintf(back, BI_VALUE " errormsg %s\n",
+			    "unable to allocate memory");
+			(void)fprintf(back, BI_REJECT "\n");
+			exit(1);
+		}
+		fprintf(back, BI_VALUE " challenge %s\n", cp);
 		fprintf(back, BI_CHALLENGE "\n");
 		if (haskey) {
 			fprintf(back, BI_FDPASS "\n");
diff --git a/libexec/login_token/login_token.c b/libexec/login_token/login_token.c
index 0ee7d2cdda4..6f11b54f6cd 100644
--- a/libexec/login_token/login_token.c
+++ b/libexec/login_token/login_token.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: login_token.c,v 1.16 2019/06/28 13:32:53 deraadt Exp $	*/
+/*	$OpenBSD: login_token.c,v 1.17 2021/01/02 20:32:20 millert Exp $	*/
 
 /*-
  * Copyright (c) 1995, 1996 Berkeley Software Design, Inc. All rights reserved.
@@ -152,8 +152,14 @@ main(int argc, char *argv[])
 		    tt->proper);
 		(void)sigprocmask(SIG_UNBLOCK, &blockset, NULL);
 		if (mode == 1) {
-			fprintf(back, BI_VALUE " challenge %s\n",
-			    auth_mkvalue(challenge));
+			char *val = auth_mkvalue(challenge);
+			if (val == NULL) {
+				(void)fprintf(back, BI_VALUE " errormsg %s\n",
+				    "unable to allocate memory");
+				(void)fprintf(back, BI_REJECT "\n");
+				exit(1);
+			}
+			fprintf(back, BI_VALUE " challenge %s\n", val);
 			fprintf(back, BI_CHALLENGE "\n");
 			exit(0);
 		}