external/dropbear 0.49upstream/0.49

1 files changed, 105 insertions, 0 deletions

diff --git a/svr-authpasswd.c b/svr-authpasswd.c
new file mode 100644
index 0000000..5be1e2a
--- /dev/null
+++ b/svr-authpasswd.c
@@ -0,0 +1,105 @@
+/*
+ * Dropbear - a SSH2 server
+ * 
+ * Copyright (c) 2002,2003 Matt Johnston
+ * All rights reserved.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE. */
+
+/* Validates a user password */
+
+#include "includes.h"
+#include "session.h"
+#include "buffer.h"
+#include "dbutil.h"
+#include "auth.h"
+
+#ifdef ENABLE_SVR_PASSWORD_AUTH
+
+/* Process a password auth request, sending success or failure messages as
+ * appropriate */
+void svr_auth_password() {
+	
+#ifdef HAVE_SHADOW_H
+	struct spwd *spasswd = NULL;
+#endif
+	char * passwdcrypt = NULL; /* the crypt from /etc/passwd or /etc/shadow */
+	char * testcrypt = NULL; /* crypt generated from the user's password sent */
+	unsigned char * password;
+	unsigned int passwordlen;
+
+	unsigned int changepw;
+
+	passwdcrypt = ses.authstate.pw->pw_passwd;
+#ifdef HAVE_SHADOW_H
+	/* get the shadow password if possible */
+	spasswd = getspnam(ses.authstate.printableuser);
+	if (spasswd != NULL && spasswd->sp_pwdp != NULL) {
+		passwdcrypt = spasswd->sp_pwdp;
+	}
+#endif
+
+#ifdef DEBUG_HACKCRYPT
+	/* debugging crypt for non-root testing with shadows */
+	passwdcrypt = DEBUG_HACKCRYPT;
+#endif
+
+	/* check for empty password - need to do this again here
+	 * since the shadow password may differ to that tested
+	 * in auth.c */
+	if (passwdcrypt[0] == '\0') {
+		dropbear_log(LOG_WARNING, "user '%s' has blank password, rejected",
+				ses.authstate.printableuser);
+		send_msg_userauth_failure(0, 1);
+		return;
+	}
+
+	/* check if client wants to change password */
+	changepw = buf_getbool(ses.payload);
+	if (changepw) {
+		/* not implemented by this server */
+		send_msg_userauth_failure(0, 1);
+		return;
+	}
+
+	password = buf_getstring(ses.payload, &passwordlen);
+
+	/* the first bytes of passwdcrypt are the salt */
+	testcrypt = crypt((char*)password, passwdcrypt);
+	m_burn(password, passwordlen);
+	m_free(password);
+
+	if (strcmp(testcrypt, passwdcrypt) == 0) {
+		/* successful authentication */
+		dropbear_log(LOG_NOTICE, 
+				"password auth succeeded for '%s' from %s",
+				ses.authstate.printableuser,
+				svr_ses.addrstring);
+		send_msg_userauth_success();
+	} else {
+		dropbear_log(LOG_WARNING,
+				"bad password attempt for '%s' from %s",
+				ses.authstate.printableuser,
+				svr_ses.addrstring);
+		send_msg_userauth_failure(0, 1);
+	}
+
+}
+
+#endif