pam-afs-password-changing-support-20010305
authorUlrich Hahn <zrsha01@zdv.uni-tuebingen.de>
Mon, 5 Mar 2001 16:22:53 +0000 (16:22 +0000)
committerDerrick Brashear <shadow@dementia.org>
Mon, 5 Mar 2001 16:22:53 +0000 (16:22 +0000)
support for changing passwords when user has kaserver password only

src/pam/afs_message.c
src/pam/afs_message.h
src/pam/afs_password.c

index 0845f9a..da3c708 100644 (file)
@@ -36,7 +36,7 @@ static char *fallback_messages[] = {
     "AFS not available",                       /* 10: AFS_UNAVAIL      */
     "AFS error code 0x%x",                     /* 11: AFS_ERROR        */
     "AFS Authentication succeeded.\n",         /* 12: LOGIN_OK         */
-    "AFS Authentication failed for user %s. %s\n",
+    "AFS Authentication failed for user %s %s\n",
                                                /* 13: LOGIN_FAILED     */
     "AFS PAM error, code=%d",                  /* 14: PAMERROR         */
     "AFS uid exceeds OS bounds.\n",            /* 15: UID_OVERFLOW     */
@@ -68,8 +68,13 @@ static char *fallback_messages[] = {
                                                /* 33: */
     "",
                                                /* 34: */
-    "AFS blindly trusting user %s\n",
-                                               /* 35: TRUSTROOT        */
+    "AFS blindly trusting user %s\n",          /* 35: TRUSTROOT        */
+    "New AFS Password: ",                       /* 36: NEW_PWD_PROMPT   */
+    "New AFS Password (again): ",               /* 37: VERIFY_PWD_PROMPT */
+    "Failed to change AFS password",            /* 38: KRBPASS_FAIL     */
+    "Missing PAM flag: %s",                     /* 39: FLAGS            */
+    "ka error, code=%d",                        /* 40: KAERROR          */
+    "Passwords are not equal"                   /* 41: NE_PASSWORD      */
 };
 
 static int num_fallbacks = sizeof(fallback_messages)/sizeof(char *);
index 6b7ec9b..8b211b0 100644 (file)
 #define PAMAFS_CHOWNKRB                33 /* "Failed to chown krb ticketfile"  */
 #define PAMAFS_KRBFAIL         34 /* "Failed to set KRBTKTFILE"        */
 #define PAMAFS_TRUSTROOT       35 /* "Ignoring superuser %s"           */
-
+#define PAMAFS_NEW_PWD_PROMPT   36 /* "New AFS Password:"               */
+#define PAMAFS_VERIFY_PWD_PROMPT  37 /* "New AFS Password (again):"     */
+#define PAMAFS_KAPASS_FAIL      38 /* "Failed to change AFS password"   */
+#define PAMAFS_FLAGS            39 /* "Missing PAM flag:"               */
+#define PAMAFS_KAERROR          40 /* "ka error, code=%d"               */
+#define PAMAFS_NE_PASSWORD      41 /* "Passwords are not equal"         */  
 
 char *pam_afs_message(int msgnum, int *freeit);
 void pam_afs_syslog(int priority, int msgid, ...);
index 3bd3dd8..c644e85 100644 (file)
@@ -9,6 +9,22 @@
 
 #include <security/pam_appl.h>
 #include <security/pam_modules.h>
+#include <syslog.h>
+#include <stdlib.h>
+#include <string.h>
+#include <pwd.h>
+#include <unistd.h>
+#include <afs/param.h>
+#include <sys/param.h>
+#include <afs/kautils.h>
+#include "afs_message.h"
+#include "afs_util.h"
+#include "afs_pam_msg.h"
+#include <signal.h>
+#include <sys/wait.h>
+#include <errno.h>
+
+#define RET(x) { retcode = (x); goto out; }
 
 extern int
 pam_sm_chauthtok(
@@ -17,5 +33,267 @@ pam_sm_chauthtok(
        int             argc,
        const char      **argv)
 {
-    return PAM_PERM_DENIED;
+    int retcode = PAM_SUCCESS;
+    int errcode = PAM_SUCCESS;
+    int code;
+    int origmask;
+    int logmask = LOG_UPTO(LOG_INFO);
+    int nowarn = 0;
+    int use_first_pass = 0;
+    int try_first_pass = 0;
+    int ignore_root = 0;
+    int got_authtok = 0;       /* got PAM_AUTHTOK upon entry */
+    int torch_password = 1;
+    int i;
+    char my_password_buf[256];
+    char instance[256];
+    char realm[256];
+    char cell[256];
+    char *localcell;
+    char *user = NULL, *password = NULL;
+    char *new_password = NULL, *verify_password = NULL;
+    char upwd_buf[2048];       /* size is a guess. */
+    char*      reason = NULL;
+    struct ktc_encryptionKey oldkey, newkey;
+    struct ktc_token token;
+    struct ubik_client *conn = 0;
+    struct pam_conv *pam_convp = NULL;
+    struct passwd unix_pwd, *upwd = NULL;
+
+#ifndef AFS_SUN56_ENV
+    openlog(pam_afs_ident, LOG_CONS, LOG_AUTH);
+#endif
+    origmask = setlogmask(logmask);
+
+    /*
+     * Parse the user options.  Log an error for any unknown options.
+     *
+     * Todo options: PAM_SILENT
+     */
+    for (i = 0; i < argc; i++) {
+       if (       strcasecmp(argv[i], "debug"         ) == 0) {
+           logmask |= LOG_MASK(LOG_DEBUG);
+           (void) setlogmask(logmask);
+       } else if (strcasecmp(argv[i], "nowarn"        ) == 0) {
+           nowarn = 1;
+       } else if (strcasecmp(argv[i], "use_first_pass") == 0) {
+           use_first_pass = 1;
+       } else if (strcasecmp(argv[i], "try_first_pass") == 0) {
+           try_first_pass = 1;
+       } else if (strcasecmp(argv[i], "ignore_root"   ) == 0) {
+           ignore_root = 1;
+       } else {
+           pam_afs_syslog(LOG_ERR, PAMAFS_UNKNOWNOPT, argv[i]);
+       }
+    }
+
+    if (use_first_pass) try_first_pass = 0;
+
+    pam_afs_syslog(LOG_DEBUG, PAMAFS_OPTIONS, nowarn, use_first_pass, try_first_pass);
+    pam_afs_syslog(LOG_DEBUG, PAMAFS_PAMERROR, flags);
+
+    /* Try to get the user-interaction info, if available. */
+    errcode = pam_get_item(pamh, PAM_CONV, (const void **) &pam_convp);
+    if (errcode != PAM_SUCCESS) {
+       pam_afs_syslog(LOG_WARNING, PAMAFS_NO_USER_INT);
+       pam_convp = NULL;
+    }
+
+    /* Who are we trying to authenticate here? */
+    if ((errcode = pam_get_user(pamh, (const char **)&user, "AFS username: ")) != PAM_SUCCESS) {
+       pam_afs_syslog(LOG_ERR, PAMAFS_NOUSER, errcode);
+       RET(PAM_USER_UNKNOWN);
+    }
+
+    pam_afs_syslog(LOG_DEBUG, PAMAFS_USERNAMEDEBUG, user);
+
+    /*
+     * If the user has a "local" (or via nss, possibly nss_dce) pwent,
+     * and its uid==0, and "ignore_root" was given in pam.conf,
+     * ignore the user.
+     */
+#if    defined(AFS_HPUX_ENV)
+#if     defined(AFS_HPUX110_ENV)
+    i = getpwnam_r(user, &unix_pwd, upwd_buf, sizeof(upwd_buf), &upwd);
+#else   /* AFS_HPUX110_ENV */
+    i = getpwnam_r(user, &unix_pwd, upwd_buf, sizeof(upwd_buf));
+    if ( i == 0 )                      /* getpwnam_r success */
+       upwd = &unix_pwd; 
+#endif  /* else AFS_HPUX110_ENV */
+    if (ignore_root && i == 0  && upwd->pw_uid == 0) {
+       pam_afs_syslog(LOG_INFO, PAMAFS_IGNORINGROOT, user);
+       RET(PAM_AUTH_ERR);
+    }
+#else
+#ifdef AFS_LINUX20_ENV
+    upwd = getpwnam(user);
+#else
+    upwd = getpwnam_r(user, &unix_pwd, upwd_buf, sizeof(upwd_buf));
+#endif
+    if (ignore_root && upwd != NULL && upwd->pw_uid == 0) {
+       pam_afs_syslog(LOG_INFO, PAMAFS_IGNORINGROOT, user);
+       RET(PAM_AUTH_ERR);
+    }
+#endif
+
+    errcode = pam_get_item(pamh, PAM_AUTHTOK, (const void **) &password);
+    if (errcode != PAM_SUCCESS || password == NULL) {
+       if (use_first_pass) {
+           pam_afs_syslog(LOG_ERR, PAMAFS_PASSWD_REQ, user);
+           RET(PAM_AUTH_ERR);
+       }
+       password = NULL;        /* In case it isn't already NULL */
+       pam_afs_syslog(LOG_DEBUG, PAMAFS_NOFIRSTPASS, user);
+    } else if (password[0] == '\0') {
+       /* Actually we *did* get one but it was empty. */
+       torch_password = 0;
+       pam_afs_syslog(LOG_INFO, PAMAFS_NILPASSWORD, user);
+       RET(PAM_NEW_AUTHTOK_REQD);
+    } else {
+       pam_afs_syslog(LOG_DEBUG, PAMAFS_GOTPASS, user);
+       torch_password = 0;
+       got_authtok = 1;
+    }
+    if (!(use_first_pass || try_first_pass)) {
+       password = NULL;
+    }
+
+    if (password == NULL) {
+       torch_password = 1;
+       if (use_first_pass)
+           RET(PAM_AUTH_ERR);  /* shouldn't happen */
+       if (try_first_pass)
+           try_first_pass = 0; 
+       if (pam_convp == NULL || pam_convp->conv == NULL) {
+           pam_afs_syslog(LOG_ERR, PAMAFS_CANNOT_PROMPT);
+           RET(PAM_AUTH_ERR);
+       }
+
+       errcode = pam_afs_prompt(pam_convp, &password, 0, PAMAFS_PWD_PROMPT);
+       if (errcode != PAM_SUCCESS || password == NULL) {
+           pam_afs_syslog(LOG_ERR, PAMAFS_GETPASS_FAILED);
+           RET(PAM_AUTH_ERR);
+       }
+       if (password[0] == '\0') {
+           pam_afs_syslog(LOG_INFO, PAMAFS_NILPASSWORD, user);
+           RET(PAM_NEW_AUTHTOK_REQD);
+       }
+
+       /*
+         * We aren't going to free the password later (we will wipe it,
+         * though), because the storage for it if we get it from other
+         * paths may belong to someone else.  Since we do need to free
+         * this storage, copy it to a buffer that won't need to be freed
+         * later, and free this storage now.
+         */
+        strncpy(my_password_buf, password, sizeof(my_password_buf));
+        my_password_buf[sizeof(my_password_buf)-1] = '\0';
+        memset(password, 0, strlen(password));
+        free(password);
+        password = my_password_buf;
+    }
+
+    if ( (code = ka_VerifyUserPassword(KA_USERAUTH_VERSION + KA_USERAUTH_DOSETPAG,
+                                   user, /* kerberos name */
+                                   (char *)0, /* instance */
+                                   (char *)0, /* realm */
+                                   password, /* password */
+                                   0, /* spare 2 */
+                                   &reason /* error string */ )) !=0 ) {
+       pam_afs_syslog(LOG_ERR, PAMAFS_LOGIN_FAILED, user, reason);
+        RET(PAM_AUTH_ERR);
+    }
+    torch_password = 0;
+    pam_set_item(pamh, PAM_AUTHTOK, password);
+    pam_set_item(pamh, PAM_OLDAUTHTOK, password);
+    if (flags & PAM_PRELIM_CHECK) {
+       /* only auth check was requested, so return success here */
+       return(PAM_SUCCESS);
+    }
+    if (!(flags & PAM_UPDATE_AUTHTOK)) {
+       /* these lines are never executed ... */
+       /* UPDATE_AUTHTOK flag is required, return with error */
+       pam_afs_syslog(LOG_ERR, PAMAFS_FLAGS, "PAM_UPDATE_AUTHTOK");
+       RET(PAM_AUTH_ERR);
+    }
+
+    /* get the new passwd and verify it */
+    errcode = pam_afs_prompt(pam_convp, &new_password, 0, PAMAFS_NEW_PWD_PROMPT);
+    if (errcode != PAM_SUCCESS || new_password == NULL) {
+        pam_afs_syslog(LOG_ERR, PAMAFS_GETPASS_FAILED);
+        RET(PAM_AUTH_ERR);
+    }
+    if (new_password[0] == '\0') {
+        pam_afs_syslog(LOG_INFO, PAMAFS_NILPASSWORD, user);
+        RET(PAM_AUTH_ERR);
+    }
+    errcode = pam_afs_prompt(pam_convp, &verify_password, 0, PAMAFS_VERIFY_PWD_PROMPT);
+    if (errcode != PAM_SUCCESS || verify_password == NULL) {
+        pam_afs_syslog(LOG_ERR, PAMAFS_GETPASS_FAILED);
+       memset(new_password, 0, strlen(new_password));
+        RET(PAM_AUTH_ERR);
+    }
+    if (verify_password[0] == '\0') {
+        pam_afs_syslog(LOG_INFO, PAMAFS_NILPASSWORD, user);
+       memset(new_password, 0, strlen(new_password));
+        RET(PAM_AUTH_ERR);
+    }
+    if (strcmp(new_password, verify_password) != 0) {
+        pam_afs_syslog(LOG_INFO, PAMAFS_NE_PASSWORD);
+       memset(new_password, 0, strlen(new_password));
+       memset(verify_password, 0, strlen(verify_password));
+        RET(PAM_AUTH_ERR);
+    }
+    memset(verify_password, 0, strlen(verify_password));
+    /* checking password length and quality is up to other PAM modules */ 
+
+    /* set the new password */
+    if ((code = ka_Init(0)) != 0) {
+        pam_afs_syslog(LOG_ERR, PAMAFS_KAERROR, code);
+        RET(PAM_AUTH_ERR);
+    }
+    if ((code = rx_Init(0)) != 0) {
+        pam_afs_syslog(LOG_ERR, PAMAFS_KAERROR, code);
+        RET(PAM_AUTH_ERR);
+    }
+    strcpy(instance,"");
+    if ((localcell = ka_LocalCell()) == NULL) {
+        pam_afs_syslog(LOG_ERR, PAMAFS_NOCELLNAME);
+        RET(PAM_AUTH_ERR);
+    }
+    strcpy(realm,localcell);
+    strcpy(cell,realm);
+    /* oldkey is not used in ka_ChangePassword (only for ka_auth) */
+    ka_StringToKey(password, realm, &oldkey);
+    ka_StringToKey(new_password, realm, &newkey);
+    if ((code = ka_GetAdminToken(user, instance, realm, &oldkey, 20, &token, 0)) != 0) {
+        pam_afs_syslog(LOG_ERR, PAMAFS_KAERROR, code);
+        RET(PAM_AUTH_ERR);
+    }
+    if ((code = ka_AuthServerConn(realm, KA_MAINTENANCE_SERVICE, &token, &conn)) != 0) { 
+        pam_afs_syslog(LOG_ERR, PAMAFS_KAERROR, code);
+        RET(PAM_AUTH_ERR);
+    }
+    if ((code = ka_ChangePassword(user,     /* kerberos name */
+                                 instance, /* instance */
+                                 conn,     /* conn */
+                                 0,        /* old password unused */
+                                 &newkey   /* new password */ )) != 0) {
+       pam_afs_syslog(LOG_ERR, PAMAFS_KAPASS_FAIL);
+        memset(new_password, 0, strlen(new_password));
+        RET(PAM_AUTH_ERR);
+    } else {
+        pam_set_item(pamh, PAM_AUTHTOK, new_password);
+        RET(PAM_SUCCESS);
+    }
+       
+ out:
+    if (password && torch_password) {
+        memset(password, 0, strlen(password));
+    }
+    (void) setlogmask(origmask);
+#ifndef AFS_SUN56_ENV
+    closelog();
+#endif
+    return retcode;
 }