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/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/*
* kadmin/ktutil/ktutil_funcs.c
*
*(C) Copyright 1995, 1996 by the Massachusetts Institute of Technology.
* All Rights Reserved.
*
* Export of this software from the United States of America may
* require a specific license from the United States Government.
* It is the responsibility of any person or organization contemplating
* export to obtain such a license before exporting.
*
* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
* distribute this software and its documentation for any purpose and
* without fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright notice and
* this permission notice appear in supporting documentation, and that
* the name of M.I.T. not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior
* permission. Furthermore if you modify this software you must label
* your software as modified software and not distribute it in such a
* fashion that it might be confused with the original M.I.T. software.
* M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is" without express
* or implied warranty.
*
* Utility functions for ktutil.
*/
#include "k5-int.h"
#include "ktutil.h"
#include <string.h>
#include <ctype.h>
/*
* Free a kt_list
*/
krb5_error_code ktutil_free_kt_list(context, list)
krb5_context context;
krb5_kt_list list;
{
krb5_kt_list lp, prev;
krb5_error_code retval = 0;
for (lp = list; lp;) {
retval = krb5_kt_free_entry(context, lp->entry);
free(lp->entry);
if (retval)
break;
prev = lp;
lp = lp->next;
free(prev);
}
return retval;
}
/*
* Delete a numbered entry in a kt_list. Takes a pointer to a kt_list
* in case head gets deleted.
*/
krb5_error_code ktutil_delete(context, list, idx)
krb5_context context;
krb5_kt_list *list;
int idx;
{
krb5_kt_list lp, prev;
int i;
for (lp = *list, i = 1; lp; prev = lp, lp = lp->next, i++) {
if (i == idx) {
if (i == 1)
*list = lp->next;
else
prev->next = lp->next;
lp->next = NULL;
return ktutil_free_kt_list(context, lp);
}
}
return EINVAL;
}
/*
* Create a new keytab entry and add it to the keytab list.
* Based on the value of use_pass, either prompt the user for a
* password or key. If the keytab list is NULL, allocate a new
* one first.
*/
krb5_error_code ktutil_add(context, list, princ_str, kvno,
enctype_str, use_pass)
krb5_context context;
krb5_kt_list *list;
char *princ_str;
krb5_kvno kvno;
char *enctype_str;
int use_pass;
{
krb5_keytab_entry *entry;
krb5_kt_list lp = NULL, prev = NULL;
krb5_principal princ;
krb5_enctype enctype;
krb5_timestamp now;
krb5_error_code retval;
krb5_data password, salt;
krb5_keyblock key;
char buf[BUFSIZ];
char promptstr[1024];
char *cp;
int i, tmp;
unsigned int pwsize = BUFSIZ;
retval = krb5_parse_name(context, princ_str, &princ);
if (retval)
return retval;
/* now unparse in order to get the default realm appended
to princ_str, if no realm was specified */
retval = krb5_unparse_name(context, princ, &princ_str);
if (retval)
return retval;
retval = krb5_string_to_enctype(enctype_str, &enctype);
if (retval)
return KRB5_BAD_ENCTYPE;
retval = krb5_timeofday(context, &now);
if (retval)
return retval;
if (*list) {
/* point lp at the tail of the list */
for (lp = *list; lp->next; lp = lp->next);
}
entry = (krb5_keytab_entry *) malloc(sizeof(krb5_keytab_entry));
if (!entry) {
return ENOMEM;
}
memset(entry, 0, sizeof(*entry));
if (!lp) { /* if list is empty, start one */
lp = (krb5_kt_list) malloc(sizeof(*lp));
if (!lp) {
return ENOMEM;
}
} else {
lp->next = (krb5_kt_list) malloc(sizeof(*lp));
if (!lp->next) {
return ENOMEM;
}
prev = lp;
lp = lp->next;
}
lp->next = NULL;
lp->entry = entry;
if (use_pass) {
password.length = pwsize;
password.data = (char *) malloc(pwsize);
if (!password.data) {
retval = ENOMEM;
goto cleanup;
}
snprintf(promptstr, sizeof(promptstr), "Password for %.1000s",
princ_str);
retval = krb5_read_password(context, promptstr, NULL, password.data,
&password.length);
if (retval)
goto cleanup;
retval = krb5_principal2salt(context, princ, &salt);
if (retval)
goto cleanup;
retval = krb5_c_string_to_key(context, enctype, &password,
&salt, &key);
if (retval)
goto cleanup;
memset(password.data, 0, password.length);
password.length = 0;
lp->entry->key = key;
} else {
printf("Key for %s (hex): ", princ_str);
fgets(buf, BUFSIZ, stdin);
/*
* We need to get rid of the trailing '\n' from fgets.
* If we have an even number of hex digits (as we should),
* write a '\0' over the '\n'. If for some reason we have
* an odd number of hex digits, force an even number of hex
* digits by writing a '0' into the last position (the string
* will still be null-terminated).
*/
buf[strlen(buf) - 1] = strlen(buf) % 2 ? '\0' : '0';
if (strlen(buf) == 0) {
fprintf(stderr, "addent: Error reading key.\n");
retval = 0;
goto cleanup;
}
lp->entry->key.enctype = enctype;
lp->entry->key.contents = (krb5_octet *) malloc((strlen(buf) + 1) / 2);
if (!lp->entry->key.contents) {
retval = ENOMEM;
goto cleanup;
}
i = 0;
for (cp = buf; *cp; cp += 2) {
if (!isxdigit((int) cp[0]) || !isxdigit((int) cp[1])) {
fprintf(stderr, "addent: Illegal character in key.\n");
retval = 0;
goto cleanup;
}
sscanf(cp, "%02x", &tmp);
lp->entry->key.contents[i++] = (krb5_octet) tmp;
}
lp->entry->key.length = i;
}
lp->entry->principal = princ;
lp->entry->vno = kvno;
lp->entry->timestamp = now;
if (!*list)
*list = lp;
return 0;
cleanup:
if (prev)
prev->next = NULL;
ktutil_free_kt_list(context, lp);
return retval;
}
/*
* Read in a keytab and append it to list. If list starts as NULL,
* allocate a new one if necessary.
*/
krb5_error_code ktutil_read_keytab(context, name, list)
krb5_context context;
char *name;
krb5_kt_list *list;
{
krb5_kt_list lp = NULL, tail = NULL, back = NULL;
krb5_keytab kt;
krb5_keytab_entry *entry;
krb5_kt_cursor cursor;
krb5_error_code retval = 0;
if (*list) {
/* point lp at the tail of the list */
for (lp = *list; lp->next; lp = lp->next);
back = lp;
}
retval = krb5_kt_resolve(context, name, &kt);
if (retval)
return retval;
retval = krb5_kt_start_seq_get(context, kt, &cursor);
if (retval)
goto close_kt;
for (;;) {
entry = (krb5_keytab_entry *)malloc(sizeof (krb5_keytab_entry));
if (!entry) {
retval = ENOMEM;
break;
}
memset(entry, 0, sizeof (*entry));
retval = krb5_kt_next_entry(context, kt, entry, &cursor);
if (retval)
break;
if (!lp) { /* if list is empty, start one */
lp = (krb5_kt_list)malloc(sizeof (*lp));
if (!lp) {
retval = ENOMEM;
break;
}
} else {
lp->next = (krb5_kt_list)malloc(sizeof (*lp));
if (!lp->next) {
retval = ENOMEM;
break;
}
lp = lp->next;
}
if (!tail)
tail = lp;
lp->next = NULL;
lp->entry = entry;
}
if (entry)
free(entry);
if (retval) {
if (retval == KRB5_KT_END)
retval = 0;
else {
ktutil_free_kt_list(context, tail);
tail = NULL;
if (back)
back->next = NULL;
}
}
if (!*list)
*list = tail;
krb5_kt_end_seq_get(context, kt, &cursor);
close_kt:
krb5_kt_close(context, kt);
return retval;
}
/*
* Takes a kt_list and writes it to the named keytab.
*/
krb5_error_code ktutil_write_keytab(context, list, name)
krb5_context context;
krb5_kt_list list;
char *name;
{
krb5_kt_list lp;
krb5_keytab kt;
char ktname[MAXPATHLEN+sizeof("WRFILE:")+1];
krb5_error_code retval = 0;
int result;
result = snprintf(ktname, sizeof(ktname), "WRFILE:%s", name);
if (SNPRINTF_OVERFLOW(result, sizeof(ktname)))
return ENAMETOOLONG;
retval = krb5_kt_resolve(context, ktname, &kt);
if (retval)
return retval;
for (lp = list; lp; lp = lp->next) {
retval = krb5_kt_add_entry(context, kt, lp->entry);
if (retval)
break;
}
krb5_kt_close(context, kt);
return retval;
}
/*
* Read in a named krb4 srvtab and append to list. Allocate new list
* if needed.
*/
krb5_error_code ktutil_read_srvtab(context, name, list)
krb5_context context;
char *name;
krb5_kt_list *list;
{
char *ktname;
krb5_error_code result;
if (asprintf(&ktname, "SRVTAB:%s", name) < 0)
return ENOMEM;
result = ktutil_read_keytab(context, ktname, list);
free(ktname);
return result;
}
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