diff options
Diffstat (limited to 'crypto/kerberosIV/lib/krb/read_service_key.c')
| -rw-r--r-- | crypto/kerberosIV/lib/krb/read_service_key.c | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/crypto/kerberosIV/lib/krb/read_service_key.c b/crypto/kerberosIV/lib/krb/read_service_key.c new file mode 100644 index 0000000..6de5db2 --- /dev/null +++ b/crypto/kerberosIV/lib/krb/read_service_key.c @@ -0,0 +1,116 @@ +/* + Copyright (C) 1989 by the Massachusetts Institute of Technology + + Export of this software from the United States of America is assumed + to 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. 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. + + */ + +#include "krb_locl.h" + +RCSID("$Id: read_service_key.c,v 1.8 1997/03/23 03:53:16 joda Exp $"); + +/* + * The private keys for servers on a given host are stored in a + * "srvtab" file (typically "/etc/srvtab"). This routine extracts + * a given server's key from the file. + * + * read_service_key() takes the server's name ("service"), "instance", + * and "realm" and a key version number "kvno", and looks in the given + * "file" for the corresponding entry, and if found, returns the entry's + * key field in "key". + * + * If "instance" contains the string "*", then it will match + * any instance, and the chosen instance will be copied to that + * string. For this reason it is important that the there is enough + * space beyond the "*" to receive the entry. + * + * If "kvno" is 0, it is treated as a wild card and the first + * matching entry regardless of the "vno" field is returned. + * + * This routine returns KSUCCESS on success, otherwise KFAILURE. + * + * The format of each "srvtab" entry is as follows: + * + * Size Variable Field in file + * ---- -------- ------------- + * string serv server name + * string inst server instance + * string realm server realm + * 1 byte vno server key version # + * 8 bytes key server's key + * ... ... ... + */ + + +int +read_service_key(char *service, /* Service Name */ + char *instance, /* Instance name or "*" */ + char *realm, /* Realm */ + int kvno, /* Key version number */ + char *file, /* Filename */ + char *key) /* Pointer to key to be filled in */ +{ + char serv[SNAME_SZ]; + char inst[INST_SZ]; + char rlm[REALM_SZ]; + unsigned char vno; /* Key version number */ + int wcard; + + int stab; + + if ((stab = open(file, O_RDONLY, 0)) < 0) + return(KFAILURE); + + wcard = (instance[0] == '*') && (instance[1] == '\0'); + + while (getst(stab,serv,SNAME_SZ) > 0) { /* Read sname */ + getst(stab,inst,INST_SZ); /* Instance */ + getst(stab,rlm,REALM_SZ); /* Realm */ + /* Vers number */ + if (read(stab, &vno, 1) != 1) { + close(stab); + return(KFAILURE); + } + /* Key */ + if (read(stab,key,8) != 8) { + close(stab); + return(KFAILURE); + } + /* Is this the right service */ + if (strcmp(serv,service)) + continue; + /* How about instance */ + if (!wcard && strcmp(inst,instance)) + continue; + if (wcard) + strncpy(instance,inst,INST_SZ); + /* Is this the right realm */ + if (strcmp(rlm,realm)) + continue; + + /* How about the key version number */ + if (kvno && kvno != (int) vno) + continue; + + close(stab); + return(KSUCCESS); + } + + /* Can't find the requested service */ + close(stab); + return(KFAILURE); +} |
