1 /* 2 * Dropbear - a SSH2 server 3 * 4 * Copyright (c) 2002,2003 Matt Johnston 5 * All rights reserved. 6 * 7 * Permission is hereby granted, free of charge, to any person obtaining a copy 8 * of this software and associated documentation files (the "Software"), to deal 9 * in the Software without restriction, including without limitation the rights 10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 11 * copies of the Software, and to permit persons to whom the Software is 12 * furnished to do so, subject to the following conditions: 13 * 14 * The above copyright notice and this permission notice shall be included in 15 * all copies or substantial portions of the Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 20 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 23 * SOFTWARE. */ 24 25 /* Validates a user password */ 26 27 #include "includes.h" 28 #include "session.h" 29 #include "buffer.h" 30 #include "dbutil.h" 31 #include "auth.h" 32 33 #ifdef ENABLE_SVR_PASSWORD_AUTH 34 35 /* Process a password auth request, sending success or failure messages as 36 * appropriate */ 37 void svr_auth_password() { 38 39 #ifdef HAVE_SHADOW_H 40 struct spwd *spasswd = NULL; 41 #endif 42 char * passwdcrypt = NULL; /* the crypt from /etc/passwd or /etc/shadow */ 43 char * testcrypt = NULL; /* crypt generated from the user's password sent */ 44 unsigned char * password; 45 unsigned int passwordlen; 46 47 unsigned int changepw; 48 49 passwdcrypt = ses.authstate.pw->pw_passwd; 50 #ifdef HAVE_SHADOW_H 51 /* get the shadow password if possible */ 52 spasswd = getspnam(ses.authstate.printableuser); 53 if (spasswd != NULL && spasswd->sp_pwdp != NULL) { 54 passwdcrypt = spasswd->sp_pwdp; 55 } 56 #endif 57 58 #ifdef DEBUG_HACKCRYPT 59 /* debugging crypt for non-root testing with shadows */ 60 passwdcrypt = DEBUG_HACKCRYPT; 61 #endif 62 63 /* check for empty password - need to do this again here 64 * since the shadow password may differ to that tested 65 * in auth.c */ 66 if (passwdcrypt[0] == '\0') { 67 dropbear_log(LOG_WARNING, "user '%s' has blank password, rejected", 68 ses.authstate.printableuser); 69 send_msg_userauth_failure(0, 1); 70 return; 71 } 72 73 /* check if client wants to change password */ 74 changepw = buf_getbool(ses.payload); 75 if (changepw) { 76 /* not implemented by this server */ 77 send_msg_userauth_failure(0, 1); 78 return; 79 } 80 81 password = buf_getstring(ses.payload, &passwordlen); 82 83 /* the first bytes of passwdcrypt are the salt */ 84 testcrypt = crypt((char*)password, passwdcrypt); 85 m_burn(password, passwordlen); 86 m_free(password); 87 88 if (strcmp(testcrypt, passwdcrypt) == 0) { 89 /* successful authentication */ 90 dropbear_log(LOG_NOTICE, 91 "password auth succeeded for '%s' from %s", 92 ses.authstate.printableuser, 93 svr_ses.addrstring); 94 send_msg_userauth_success(); 95 } else { 96 dropbear_log(LOG_WARNING, 97 "bad password attempt for '%s' from %s", 98 ses.authstate.printableuser, 99 svr_ses.addrstring); 100 send_msg_userauth_failure(0, 1); 101 } 102 103 } 104 105 #endif 106
