fix loading of passphrase-protected keys.

3 files changed, 64 insertions, 24 deletions

diff --git a/usr.sbin/smtpd/smtpd.c b/usr.sbin/smtpd/smtpd.c
index 479a0391d02..6520e519a6e 100644
--- a/usr.sbin/smtpd/smtpd.c
+++ b/usr.sbin/smtpd/smtpd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: smtpd.c,v 1.206 2013/11/13 13:02:44 eric Exp $	*/
+/*	$OpenBSD: smtpd.c,v 1.207 2013/11/28 12:50:40 eric Exp $	*/
 
 /*
  * Copyright (c) 2008 Gilles Chehade <gilles@poolp.org>
@@ -742,6 +742,8 @@ main(int argc, char *argv[])
 	log_init(foreground);
 	log_verbose(verbose);
 
+	load_ssl_tree();
+
 	log_info("info: %s %s starting", SMTPD_NAME, SMTPD_VERSION);
 
 	if (! foreground)
@@ -764,8 +766,6 @@ main(int argc, char *argv[])
 		errx(1, "machine does not have a hostname set");
 	env->sc_uptime = time(NULL);
 
-	load_ssl_tree();
-
 	fork_peers();
 
 	config_process(PROC_PARENT);
@@ -827,24 +827,23 @@ load_ssl_tree(void)
 	log_debug("debug: init ssl-tree");
 	iter_dict = NULL;
 	while (dict_iter(env->sc_ssl_dict, &iter_dict, &k, (void **)&ssl)) {
-		log_debug("debug: loading pki information for %s", k);
-
+		log_debug("info: loading pki information for %s", k);
 		if (ssl->ssl_cert_file == NULL)
-			errx(1, "load_ssl_tree: missing certificate file for %s", k);
+			fatalx("load_ssl_tree: missing certificate file");
 		if (ssl->ssl_key_file == NULL)
-			errx(1, "load_ssl_tree: missing key file for %s", k);
+			fatalx("load_ssl_tree: missing key file");
 
 		if (! ssl_load_certificate(ssl, ssl->ssl_cert_file))
-			errx(1, "load_ssl_tree: failed to load certificate file for %s", k);
-		if (! ssl_load_keyfile(ssl, ssl->ssl_key_file))
-			errx(1, "load_ssl_tree: failed to load certificate file for %s", k);
+			fatalx("load_ssl_tree: failed to load certificate file");
+		if (! ssl_load_keyfile(ssl, ssl->ssl_key_file, k))
+			fatalx("load_ssl_tree: failed to load key file");
 
 		if (ssl->ssl_ca_file)
 			if (! ssl_load_cafile(ssl, ssl->ssl_ca_file))
-				errx(1, "load_ssl_tree: failed to load CA file for %s", k);
+				fatalx("load_ssl_tree: failed to load CA file");
 		if (ssl->ssl_dhparams_file)
 			if (! ssl_load_dhparams(ssl, ssl->ssl_dhparams_file))
-				errx(1, "load_ssl_tree: failed to load dhparams file for %s", k);
+				fatalx("load_ssl_tree: failed to load dhparams file");
 	}
 }
 
diff --git a/usr.sbin/smtpd/ssl.c b/usr.sbin/smtpd/ssl.c
index 7b7adb8fd54..b6c064711f2 100644
--- a/usr.sbin/smtpd/ssl.c
+++ b/usr.sbin/smtpd/ssl.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ssl.c,v 1.56 2013/11/06 10:01:29 eric Exp $	*/
+/*	$OpenBSD: ssl.c,v 1.57 2013/11/28 12:50:40 eric Exp $	*/
 
 /*
  * Copyright (c) 2008 Pierre-Yves Ritschard <pyr@openbsd.org>
@@ -146,6 +146,7 @@ fail:
 	return (NULL);
 }
 
+#if 0
 static int
 ssl_password_cb(char *buf, int size, int rwflag, void *u)
 {
@@ -158,15 +159,39 @@ ssl_password_cb(char *buf, int size, int rwflag, void *u)
 		return (0);
 	return (len);
 }
+#endif
+
+static int
+ssl_getpass_cb(char *buf, int size, int rwflag, void *u)
+{
+	int	ret = 0;
+	size_t	len;
+	char	*pass;
+
+	pass = getpass((const char *)u);
+	if (pass == NULL)
+		return 0;
+	len = strlen(pass);
+	if (strlcpy(buf, pass, size) >= (size_t)size)
+		goto end;
+	ret = len;
+end:
+	if (len)
+		bzero(pass, len);
+	return ret;
+}
 
 char *
-ssl_load_key(const char *name, off_t *len, char *pass)
+ssl_load_key(const char *name, off_t *len, char *pass, mode_t perm, const char *pkiname)
 {
 	FILE		*fp;
 	EVP_PKEY	*key = NULL;
 	BIO		*bio = NULL;
 	long		 size;
 	char		*data, *buf = NULL;
+	struct stat	 st;
+	char		 mode[12];
+	char		 prompt[2048];
 
 	/* Initialize SSL library once */
 	ssl_init();
@@ -177,11 +202,26 @@ ssl_load_key(const char *name, off_t *len, char *pass)
 	if ((fp = fopen(name, "r")) == NULL)
 		return (NULL);
 
-	key = PEM_read_PrivateKey(fp, NULL, ssl_password_cb, pass);
+	if (fstat(fileno(fp), &st) != 0)
+		goto fail;
+	if (st.st_uid != 0) {
+		log_warnx("warn:  %s: not owned by uid 0", name);
+		errno = EACCES;
+		goto fail;
+	}
+	if (st.st_mode & (S_IRWXU | S_IRWXG | S_IRWXO) & ~perm) {
+		strmode(perm, mode);
+		log_warnx("warn:  %s: insecure permissions: must be at most %s",
+		    name, &mode[1]);
+		errno = EACCES;
+		goto fail;
+	}
+
+	(void)snprintf(prompt, sizeof prompt, "passphrase for %s: ", pkiname);
+	key = PEM_read_PrivateKey(fp, NULL, ssl_getpass_cb, prompt);
 	fclose(fp);
 	if (key == NULL)
 		goto fail;
-
 	/*
 	 * Write unencrypted key to memory buffer
 	 */
@@ -191,17 +231,16 @@ ssl_load_key(const char *name, off_t *len, char *pass)
 		goto fail;
 	if ((size = BIO_get_mem_data(bio, &data)) <= 0)
 		goto fail;
-	if ((buf = calloc(1, size)) == NULL)
+	if ((buf = calloc(1, size + 1)) == NULL)
 		goto fail;
 	memcpy(buf, data, size);
 
 	BIO_free_all(bio);
-	*len = (off_t)size;
+	*len = (off_t)size + 1;
 	return (buf);
 
 fail:
 	ssl_error("ssl_load_key");
-
 	free(buf);
 	if (bio != NULL)
 		BIO_free_all(bio);
@@ -244,9 +283,11 @@ ssl_load_certificate(struct ssl *s, const char *pathname)
 }
 
 int
-ssl_load_keyfile(struct ssl *s, const char *pathname)
+ssl_load_keyfile(struct ssl *s, const char *pathname, const char *pkiname)
 {
-	s->ssl_key = ssl_load_file(pathname, &s->ssl_key_len, 0700);
+	char	pass[1024];
+
+	s->ssl_key = ssl_load_key(pathname, &s->ssl_key_len, pass, 0700, pkiname);
 	if (s->ssl_key == NULL)
 		return 0;
 	return 1;
diff --git a/usr.sbin/smtpd/ssl.h b/usr.sbin/smtpd/ssl.h
index 9d127beffac..cbf5574da4b 100644
--- a/usr.sbin/smtpd/ssl.h
+++ b/usr.sbin/smtpd/ssl.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ssl.h,v 1.3 2013/11/06 10:01:29 eric Exp $	*/
+/*	$OpenBSD: ssl.h,v 1.4 2013/11/28 12:50:40 eric Exp $	*/
 /*
  * Copyright (c) 2013 Gilles Chehade <gilles@poolp.org>
  *
@@ -52,13 +52,13 @@ void		ssl_set_ephemeral_key_exchange(SSL_CTX *, DH *);
 void		ssl_set_ecdh_curve(SSL_CTX *);
 extern int	ssl_ctx_load_verify_memory(SSL_CTX *, char *, off_t);
 char	       *ssl_load_file(const char *, off_t *, mode_t);
-char	       *ssl_load_key(const char *, off_t *, char *);
+char	       *ssl_load_key(const char *, off_t *, char *, mode_t, const char *);
 
 const char     *ssl_to_text(const SSL *);
 void		ssl_error(const char *);
 
 int		ssl_load_certificate(struct ssl *, const char *);
-int		ssl_load_keyfile(struct ssl *, const char *);
+int		ssl_load_keyfile(struct ssl *, const char *, const char *);
 int		ssl_load_cafile(struct ssl *, const char *);
 int		ssl_load_dhparams(struct ssl *, const char *);