X-Git-Url: http://andersk.mit.edu/gitweb/openssh.git/blobdiff_plain/1acc8e56c2db711d0185f8af02621856dc71c271..HEAD:/auth.c

diff --git a/auth.c b/auth.c
index 5d23343b..da87807a 100644
--- a/auth.c
+++ b/auth.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: auth.c,v 1.75 2006/08/03 03:34:41 deraadt Exp $ */
+/* $OpenBSD: auth.c,v 1.83 2010/01/13 23:47:26 djm Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  *
@@ -32,6 +32,7 @@
 #include <netinet/in.h>
 
 #include <errno.h>
+#include <fcntl.h>
 #ifdef HAVE_PATHS_H
 # include <paths.h>
 #endif
@@ -48,6 +49,7 @@
 #include <stdarg.h>
 #include <stdio.h>
 #include <string.h>
+#include <unistd.h>
 
 #include "xmalloc.h"
 #include "match.h"
@@ -93,7 +95,7 @@ allowed_user(struct passwd * pw)
 {
 	struct stat st;
 	const char *hostname = NULL, *ipaddr = NULL, *passwd = NULL;
-	char *shell;
+	char *shell, *tmp, *chroot_path;
 	u_int i;
 #ifdef USE_SHADOW
 	struct spwd *spw = NULL;
@@ -113,15 +115,14 @@ allowed_user(struct passwd * pw)
 #endif /* USE_SHADOW */
 
 	/* grab passwd field for locked account check */
+	passwd = pw->pw_passwd;
 #ifdef USE_SHADOW
 	if (spw != NULL)
-#if defined(HAVE_LIBIAF)  &&  !defined(BROKEN_LIBIAF)
+#ifdef USE_LIBIAF
 		passwd = get_iaf_password(pw);
 #else
 		passwd = spw->sp_pwdp;
-#endif /* HAVE_LIBIAF  && !BROKEN_LIBIAF */
-#else
-	passwd = pw->pw_passwd;
+#endif /* USE_LIBIAF */
 #endif
 
 	/* check for locked account */
@@ -141,9 +142,9 @@ allowed_user(struct passwd * pw)
 		if (strstr(passwd, LOCKED_PASSWD_SUBSTR))
 			locked = 1;
 #endif
-#if defined(HAVE_LIBIAF)  &&  !defined(BROKEN_LIBIAF)
+#ifdef USE_LIBIAF
 		free(passwd);
-#endif /* HAVE_LIBIAF  && !BROKEN_LIBIAF */
+#endif /* USE_LIBIAF */
 		if (locked) {
 			logit("User %.100s not allowed because account is locked",
 			    pw->pw_name);
@@ -155,20 +156,40 @@ allowed_user(struct passwd * pw)
 	 * Get the shell from the password data.  An empty shell field is
 	 * legal, and means /bin/sh.
 	 */
-	shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
+	shell = xstrdup((pw->pw_shell[0] == '\0') ?
+	    _PATH_BSHELL : pw->pw_shell);
+
+	/*
+	 * Amend shell if chroot is requested.
+	 */
+	if (options.chroot_directory != NULL &&
+	    strcasecmp(options.chroot_directory, "none") != 0) {
+		tmp = tilde_expand_filename(options.chroot_directory,
+		    pw->pw_uid);
+		chroot_path = percent_expand(tmp, "h", pw->pw_dir,
+		    "u", pw->pw_name, (char *)NULL);
+		xfree(tmp);
+		xasprintf(&tmp, "%s/%s", chroot_path, shell);
+		xfree(shell);
+		shell = tmp;
+		free(chroot_path);
+	}
 
 	/* deny if shell does not exists or is not executable */
 	if (stat(shell, &st) != 0) {
 		logit("User %.100s not allowed because shell %.100s does not exist",
 		    pw->pw_name, shell);
+		xfree(shell);
 		return 0;
 	}
 	if (S_ISREG(st.st_mode) == 0 ||
 	    (st.st_mode & (S_IXOTH|S_IXUSR|S_IXGRP)) == 0) {
 		logit("User %.100s not allowed because shell %.100s is not executable",
 		    pw->pw_name, shell);
+		xfree(shell);
 		return 0;
 	}
+	xfree(shell);
 
 	if (options.num_deny_users > 0 || options.num_allow_users > 0 ||
 	    options.num_deny_groups > 0 || options.num_allow_groups > 0) {
@@ -410,7 +431,7 @@ check_key_in_hostfiles(struct passwd *pw, Key *key, const char *host,
  *
  * Returns 0 on success and -1 on failure
  */
-int
+static int
 secure_filename(FILE *f, const char *file, struct passwd *pw,
     char *err, size_t errlen)
 {
@@ -454,7 +475,7 @@ secure_filename(FILE *f, const char *file, struct passwd *pw,
 			return -1;
 		}
 
-		/* If are passed the homedir then we can stop */
+		/* If are past the homedir then we can stop */
 		if (comparehome && strcmp(homedir, buf) == 0) {
 			debug3("secure_filename: terminating check at '%s'",
 			    buf);
@@ -470,6 +491,50 @@ secure_filename(FILE *f, const char *file, struct passwd *pw,
 	return 0;
 }
 
+FILE *
+auth_openkeyfile(const char *file, struct passwd *pw, int strict_modes)
+{
+	char line[1024];
+	struct stat st;
+	int fd;
+	FILE *f;
+
+	/*
+	 * Open the file containing the authorized keys
+	 * Fail quietly if file does not exist
+	 */
+	if ((fd = open(file, O_RDONLY|O_NONBLOCK)) == -1) {
+		if (errno != ENOENT)
+			debug("Could not open keyfile '%s': %s", file,
+			   strerror(errno));
+		return NULL;
+	}
+
+	if (fstat(fd, &st) < 0) {
+		close(fd);
+		return NULL;
+	}
+	if (!S_ISREG(st.st_mode)) {
+		logit("User %s authorized keys %s is not a regular file",
+		    pw->pw_name, file);
+		close(fd);
+		return NULL;
+	}
+	unset_nonblock(fd);
+	if ((f = fdopen(fd, "r")) == NULL) {
+		close(fd);
+		return NULL;
+	}
+	if (options.strict_modes &&
+	    secure_filename(f, file, pw, line, sizeof(line)) != 0) {
+		fclose(f);
+		logit("Authentication refused: %s", line);
+		return NULL;
+	}
+
+	return f;
+}
+
 struct passwd *
 getpwnamallow(const char *user)
 {
@@ -569,8 +634,8 @@ fakepw(void)
 	fake.pw_passwd =
 	    "$2a$06$r3.juUaHZDlIbQaO2dS9FuYxL1W9M81R1Tc92PoSNmzvpEqLkLGrK";
 	fake.pw_gecos = "NOUSER";
-	fake.pw_uid = privsep_pw->pw_uid;
-	fake.pw_gid = privsep_pw->pw_gid;
+	fake.pw_uid = privsep_pw == NULL ? (uid_t)-1 : privsep_pw->pw_uid;
+	fake.pw_gid = privsep_pw == NULL ? (gid_t)-1 : privsep_pw->pw_gid;
 #ifdef HAVE_PW_CLASS_IN_PASSWD
 	fake.pw_class = "";
 #endif