diff options
Diffstat (limited to 'crypto/kerberosIV/lib/krb/kuserok.c')
-rw-r--r-- | crypto/kerberosIV/lib/krb/kuserok.c | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/crypto/kerberosIV/lib/krb/kuserok.c b/crypto/kerberosIV/lib/krb/kuserok.c new file mode 100644 index 0000000..e3d5e6b --- /dev/null +++ b/crypto/kerberosIV/lib/krb/kuserok.c @@ -0,0 +1,156 @@ +/* + * Copyright (c) 1995, 1996, 1997 Kungliga Tekniska Högskolan + * (Royal Institute of Technology, Stockholm, Sweden). + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the Kungliga Tekniska + * Högskolan and its contributors. + * + * 4. Neither the name of the Institute nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include "krb_locl.h" + +RCSID("$Id: kuserok.c,v 1.21 1997/04/01 08:18:35 joda Exp $"); + +#define OK 0 +#define NOTOK 1 +#define MAX_USERNAME 10 + +/* + * Given a Kerberos principal and a local username, determine whether + * user is authorized to login according to the authorization file + * ("~luser/.klogin" by default). Returns OK if authorized, NOTOK if + * not authorized. + * + * IMPORTANT CHANGE: To eliminate the need of making a distinction + * between the 3 cases: + * + * 1. We can't verify that a .klogin file doesn't exist (no home dir). + * 2. It's there but we aren't allowed to read it. + * 3. We can read it and ~luser@LOCALREALM is (not) included. + * + * We instead make the assumption that luser@LOCALREALM is *always* + * included. Thus it is impossible to have an empty .klogin file and + * also to exclude luser@LOCALREALM from it. Root is treated differently + * since it's home should always be available. + * + * OLD STRATEGY: + * If there is no account for "luser" on the local machine, returns + * NOTOK. If there is no authorization file, and the given Kerberos + * name "kdata" translates to the same name as "luser" (using + * krb_kntoln()), returns OK. Otherwise, if the authorization file + * can't be accessed, returns NOTOK. Otherwise, the file is read for + * a matching principal name, instance, and realm. If one is found, + * returns OK, if none is found, returns NOTOK. + * + * The file entries are in the format: + * + * name.instance@realm + * + * one entry per line. + * + */ + +int +krb_kuserok(char *name, char *instance, char *realm, char *luser) +{ + struct passwd *pwd; + char lrealm[REALM_SZ]; + FILE *f; + char line[1024]; + char file[MaxPathLen]; + struct stat st; + + pwd = getpwnam(luser); + if(pwd == NULL) + return NOTOK; + if(krb_get_lrealm(lrealm, 1)) + return NOTOK; + if(pwd->pw_uid != 0 && + strcmp(name, luser) == 0 && + strcmp(instance, "") == 0 && + strcmp(realm, lrealm) == 0) + return OK; + strcpy(file, pwd->pw_dir); + strcat(file, "/.klogin"); + + f = fopen(file, "r"); + if(f == NULL) + return NOTOK; + + /* this is not a working test in filesystems like AFS and DFS */ + if(fstat(fileno(f), &st) < 0){ + fclose(f); + return NOTOK; + } + + if(st.st_uid != pwd->pw_uid){ + fclose(f); + return NOTOK; + } + + while(fgets(line, sizeof(line), f)){ + char fname[ANAME_SZ], finst[INST_SZ], frealm[REALM_SZ]; + if(line[strlen(line) - 1] != '\n') + /* read till end of line */ + while(1){ + int c = fgetc(f); + if(c == '\n' || c == EOF) + break; + } + else + line[strlen(line) - 1] = 0; + + if(kname_parse(fname, finst, frealm, line)) + continue; + if(strcmp(name, fname)) + continue; + if(strcmp(instance, finst)) + continue; + if(frealm[0] == 0) + strcpy(frealm, lrealm); + if(strcmp(realm, frealm)) + continue; + fclose(f); + return OK; + } + fclose(f); + return NOTOK; +} + +/* compatibility interface */ + +int +kuserok(AUTH_DAT *auth, char *luser) +{ + return krb_kuserok(auth->pname, auth->pinst, auth->prealm, luser); +} + |