[moira.git] / reg_svr / admin_call.c

/*
 *	$Source$
 *	$Author$
 *	$Header$
 *
 *	Copyright (C) 1987 by the Massachusetts Institute of Technology
 *
 *	Utility functions for communication with the Kerberos admin_server
 *
 * 	Original version written by Jeffery I. Schiller, January 1987
 *	Completely gutted and rewritten by Bill Sommerfeld, August 1987
 *
 *	$Log$
 *	Revision 1.1  1987-08-07 13:50:37  wesommer
 *	Initial revision
 *
 */

#ifndef lint
static char *rcsid_admin_call_c = "$Header$";
#endif lint

#include <sys/errno.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <netinet/in.h>

#include <netdb.h>
#include <strings.h>
#include <stdio.h>

#include "admin_err.h"
#include "admin_server.h"
#include "prot.h"
#include "krb.h"

extern int krb_err_base;	/* Offset between com_err and kerberos codes */
extern int errno;		/* System call error numbers */

extern long gethostid();

static u_char *strapp();		/* string append function */

static int inited = 0;		/* are we initialized? */
static int admin_fd = -1;	/* socket to talk to admin_server. */

static struct sockaddr_in admin_addr; /* address of admin server. */
static struct sockaddr_in my_addr;    /* address bound to admin_fd. */
static int my_addr_len;		/* size of above address. */

static char krbrlm[REALM_SZ];	/* Local kerberos realm */
static char admin_errmsg[BUFSIZ]; /* Server error message */

/*
 * Initialize socket, etc. to use to talk to admin_server.
 */

int admin_call_init()
{
    register int status = 0;
    
    if (!inited) {
	struct hostent *hp;	/* host to talk to */
	struct servent *sp;	/* service to talk to */
	int on = 1;		/* ioctl argument */
	
	init_kadm_err_tbl();
	if (status = get_krbrlm(krbrlm, 1)) {
	    status += krb_err_base;
	    goto punt;
	}

	/*
	 * Locate server.
	 */

	hp = gethostbyname(KERB_HOST);
	if (!hp) {
	    status = ADMIN_UNKNOWN_HOST;
	    goto punt;
	}
	sp = getservbyname("atest3", "udp");
	if (!sp) {
	    status = ADMIN_UNKNOWN_SERVICE;
	    goto punt;
	}
	bzero((char *)&admin_addr, sizeof(admin_addr));
	admin_addr.sin_family = hp->h_addrtype;
	bcopy((char *)hp->h_addr, (char *)&admin_addr.sin_addr, hp->h_length);
	admin_addr.sin_port = sp->s_port;

	/*
	 * Set up socket.
	 */

	admin_fd = socket(hp->h_addrtype, SOCK_DGRAM, 0);
	if (admin_fd < 0) {
	    status = errno;
	    goto punt;
	}

	bzero((char *)&my_addr, sizeof(my_addr));

	my_addr.sin_family = admin_addr.sin_family;
	my_addr.sin_addr.s_addr = gethostid();

	if (bind(admin_fd, &my_addr, sizeof(my_addr)) < 0) {
	    status = errno;
	    goto punt;
	}

	my_addr_len = sizeof(my_addr);

	if (getsockname(admin_fd, (struct sockaddr *)&my_addr,
			&my_addr_len) < 0) {
	    status = errno;
	    goto punt;
	}

	if (ioctl(admin_fd, FIONBIO, (char *)&on) < 0) {
	    status = errno;
	    goto punt;
	}
	
	inited = 1;
    }
    return 0;
    
punt:
    (void) close(admin_fd);
    admin_fd = -1;
    return status;
}

/*
 * Build and transmit request to admin_server, and wait for
 * response from server.  Returns a standard error code.
 */

int
admin_call(opcode, pname, old_passwd, new_passwd, crypt_passwd)
    int opcode;
    char *pname;
    char *old_passwd;
    char *new_passwd;
    char *crypt_passwd;
{
    int status;
    register u_char *bp;	/* Pointer into buffer. */
    u_char *ep;			/* End of buffer pointer. */
    
    u_char pvt_buf[BUFSIZ];	/* private message plaintext */
    int pvt_len;		/* length of valid data in pvt_buf */

    u_char sealed_buf[BUFSIZ];	/* sealed version of private message */
    int sealed_len;		/* length of valid data in sealed_buf */
    
    u_long checksum;		/* quad_cksum of sealed request. */
    
    C_Block sess_key;		/* Session key. */
    Key_schedule sess_sched;	/* Key schedule for above. */
    
    CREDENTIALS cred;		/* Kerberos credentials. */
    KTEXT_ST authent;		/* Authenticator */
    KTEXT_ST reply;		/* Reply from admin_server */
    MSG_DAT msg_data;		/* Decrypted message */
    int attempts;		/* Number of retransmits so far */

    struct sockaddr rec_addr;	/* Address we got reply from */
    int rec_addr_len;		/* Length of that address */
    
    if (!inited) {
	status = admin_call_init();
	if (status) goto bad;
    }

    /*
     * assemble packet:
     *
     * sealed message consists of:
     * version number (one byte).
     * request code (one byte).
     * principal name (null terminated).
     * new password (in the clear, null terminated).
     * old password or instance (null terminated)
     * crypt(new password, seed) (null terminated).
     * an extra null.
     * a '\001' character.
     * This is all sealed inside a private_message, with an
     * authenticator tacked on in front.
     */

    bp = pvt_buf;
    ep = pvt_buf + sizeof(pvt_buf);
    
    *bp++ = PW_SRV_VERSION;
    *bp++ = opcode;
    if ((bp = strapp(bp, (u_char *)pname, ep)) &&
	(bp = strapp(bp, (u_char *)new_passwd, ep)) &&
	(bp = strapp(bp, (u_char *)old_passwd, ep)) &&
	(bp = strapp(bp, (u_char *)crypt_passwd, ep))) {
	*bp++ = '\0';
	*bp++ = '\1';
	pvt_len = bp - pvt_buf;
    } else {
	status = ADMIN_TOO_LONG;
	goto bad;
    }
    
    /*
     * find our session key.
     */

    if (status = get_credentials("changepw", "kerberos", krbrlm, &cred)) {
	status += krb_err_base;
	goto bad;
    }

    bcopy((char *)cred.session, (char *)sess_key, sizeof(sess_key));
    bzero((char *)cred.session, sizeof(sess_key)); /* lest we remember */

    if(key_sched(sess_key, sess_sched)) {
	status = ADMIN_BAD_KEY;
	goto bad;
    }

    /*
     * Encrypt the message using the session key.
     * Since this contains passwords, it must be kept from prying eyes.
     */

    sealed_len = mk_private_msg(pvt_buf, sealed_buf, pvt_len,
				    sess_sched, sess_key, &my_addr,
				    &admin_addr);
    if (sealed_len < 0) {
	status = ADMIN_CANT_ENCRYPT;
	goto bad;
    }

    /*
     * Checksum the cypher text, to guard against tampering in flight.
     */

    checksum = quad_cksum(sealed_buf, NULL, sealed_len, 0, sess_key);
    
    /*
     * Make an authenticator, so the server can learn the session key
     * and know who we are.
     */

    if (status = mk_ap_req(&authent, "changepw", "kerberos", krbrlm,
			   checksum)) {
	status += krb_err_base;
	goto bad;
    }

    /*
     * Add the sealed message to the end of the authenticator.
     */

    if ((authent.length + sealed_len) > MAX_KTXT_LEN) {
	status = ADMIN_TOO_LONG;
	goto bad;
    }

    bcopy(sealed_buf, authent.dat + authent.length, sealed_len);
    authent.length += sealed_len;

    /*
     * send it off, and wait for a reply.
     */

    attempts = 0;
    
    while (attempts++ < RETRY_LIMIT) {
	int active;		/* number of active fds (from select). */
	fd_set set;		/* interesting fd's. */
	struct timeval timeout;	/* timeout on select. */
	
	if (sendto(admin_fd, (char *)authent.dat, authent.length,
		   0, &admin_addr, sizeof(admin_addr)) != authent.length) {
	    status = errno;
	    goto bad;
	}

	FD_ZERO(&set);
	FD_SET(admin_fd, &set);

	timeout.tv_sec = USER_TIMEOUT;
	timeout.tv_usec = 0;
	    
	active = select(admin_fd+1, &set, (fd_set *)0, (fd_set *)0, &timeout);
	if (active < 0) {
	    status = errno;
	    goto bad;
	} else if (active == 0) continue;
	else {
	    reply.length = recvfrom(admin_fd, (char *)reply.dat,
				    sizeof(reply.dat), 0,
				    &rec_addr, &rec_addr_len);
	    if (reply.length < 0) continue;
#ifdef notdef
	    if (!bcmp(&rec_addr, &admin_addr, sizeof(admin_addr)))
		/* the spoofers are out in force.. */
		continue;
#endif notdef
	    break;		/* got one.. */
	}
    }

    if (attempts > RETRY_LIMIT) {
	status = ETIMEDOUT;
	goto bad;
    }

    if (pkt_version((&reply)) != KRB_PROT_VERSION) {
	status = ADMIN_BAD_VERSION;
	goto bad;
    }

    if ((pkt_msg_type((&reply)) & ~1) != AUTH_MSG_PRIVATE) {
	bp = reply.dat;
	if (*bp++ != KRB_PROT_VERSION) {
	    status = ADMIN_BAD_VERSION;
	    goto bad;
	}
	if (*bp++ != AUTH_MSG_ERR_REPLY) {
	    status = ADMIN_UNKNOWN_CODE;
	    goto bad;
	}
	bp += strlen((char *)bp) + 1;	/* Skip name */
	bp += strlen((char *)bp) + 1;	/* Skip instance */
	bp += strlen((char *)bp) + 1;	/* Skip realm */

	/* null-terminate error string */
	reply.dat[reply.length] = '\0'; 

	if (*bp++ == 126) {
	    status = ADMIN_SERVER_ERROR;
	    strcpy(admin_errmsg, bp);
	    goto bad;
	} else {
	    status = ADMIN_UNKNOWN_CODE;
	    goto bad;
	}
    }
    status = rd_private_msg(reply.dat, reply.length,
			    sess_sched, sess_key,
			    &admin_addr, &my_addr,
			    &msg_data);
    if (status) {
	status += krb_err_base;
	goto bad;
    }
    bp = msg_data.app_data;

    if (*bp++ != PW_SRV_VERSION) {
	status = ADMIN_BAD_VERSION;
	goto bad;
    }
    if (*bp++ != INSTALL_REPLY) {
	status = ADMIN_UNKNOWN_CODE;
	goto bad;
    }

    status = 0;
    /* fall through into cleanup */

bad:
    /*
     * Paranoia: shred all the incriminating evidence.
     * We'll let the caller shred the arguments.
     */
    bzero((char *)sess_key, sizeof(sess_key));
    bzero((char *)sess_sched, sizeof(sess_sched));
    bzero(pvt_buf, sizeof(pvt_buf));
    return status;
}

/*
 * Copies characters from source to dest, returning a pointer to the
 * point in dest after the last character copied from source.
 * If this would be greater than end, no characters are copied, and NULL
 * is returned instead.
 */

static u_char *strapp(dest, source, end)
    register u_char *dest, *source, *end;
{
    register int length = strlen(source) + 1;
    if (dest+length > end) return NULL;
    else {
	bcopy(source, dest, length);
	return dest + length;
    }
}

/*
 * Local Variables:
 * mode: c
 * c-indent-level: 4
 * c-continued-statement-offset: 4
 * c-brace-offset: -4
 * c-argdecl-indent: 4
 * c-label-offset: -4
 * End:
 */
Commit	Line	Data
718bc25c	1	/*
	2	* $Source$
	3	* $Author$
	4	* $Header$
	5	*
	6	* Copyright (C) 1987 by the Massachusetts Institute of Technology
	7	*
	8	* Utility functions for communication with the Kerberos admin_server
	9	*
	10	* Original version written by Jeffery I. Schiller, January 1987
	11	* Completely gutted and rewritten by Bill Sommerfeld, August 1987
	12	*
	13	* $Log$
	14	* Revision 1.1 1987-08-07 13:50:37 wesommer
	15	* Initial revision
	16	*
	17	*/
	18
	19	#ifndef lint
	20	static char *rcsid_admin_call_c = "$Header$";
	21	#endif lint
	22
	23	#include <sys/errno.h>
	24	#include <sys/types.h>
	25	#include <sys/time.h>
	26	#include <sys/ioctl.h>
	27	#include <sys/socket.h>
	28	#include <netinet/in.h>
	29
	30	#include <netdb.h>
	31	#include <strings.h>
	32	#include <stdio.h>
	33
	34	#include "admin_err.h"
	35	#include "admin_server.h"
	36	#include "prot.h"
	37	#include "krb.h"
	38
	39	extern int krb_err_base; /* Offset between com_err and kerberos codes */
	40	extern int errno; /* System call error numbers */
	41
	42	extern long gethostid();
	43
	44	static u_char strapp(); / string append function */
	45
	46	static int inited = 0; /* are we initialized? */
	47	static int admin_fd = -1; /* socket to talk to admin_server. */
	48
	49	static struct sockaddr_in admin_addr; /* address of admin server. */
	50	static struct sockaddr_in my_addr; /* address bound to admin_fd. */
	51	static int my_addr_len; /* size of above address. */
	52
	53	static char krbrlm[REALM_SZ]; /* Local kerberos realm */
	54	static char admin_errmsg[BUFSIZ]; /* Server error message */
	55
	56	/*
	57	* Initialize socket, etc. to use to talk to admin_server.
	58	*/
	59
	60	int admin_call_init()
	61	{
	62	register int status = 0;
	63
	64	if (!inited) {
65	struct hostent hp; / host to talk to */
66	struct servent sp; / service to talk to */
67	int on = 1; /* ioctl argument */
68
69	init_kadm_err_tbl();
70	if (status = get_krbrlm(krbrlm, 1)) {
71	status += krb_err_base;
72	goto punt;
73	}
74
75	/*
76	* Locate server.
77	*/
78
79	hp = gethostbyname(KERB_HOST);
80	if (!hp) {
81	status = ADMIN_UNKNOWN_HOST;
82	goto punt;
83	}
84	sp = getservbyname("atest3", "udp");
85	if (!sp) {
86	status = ADMIN_UNKNOWN_SERVICE;
87	goto punt;
88	}
89	bzero((char *)&admin_addr, sizeof(admin_addr));
90	admin_addr.sin_family = hp->h_addrtype;
91	bcopy((char )hp->h_addr, (char )&admin_addr.sin_addr, hp->h_length);
92	admin_addr.sin_port = sp->s_port;
93
94	/*
95	* Set up socket.
96	*/
97
98	admin_fd = socket(hp->h_addrtype, SOCK_DGRAM, 0);
99	if (admin_fd < 0) {
100	status = errno;
101	goto punt;
102	}
103
104	bzero((char *)&my_addr, sizeof(my_addr));
105
106	my_addr.sin_family = admin_addr.sin_family;
107	my_addr.sin_addr.s_addr = gethostid();
108
109	if (bind(admin_fd, &my_addr, sizeof(my_addr)) < 0) {
110	status = errno;
111	goto punt;
112	}
113
114	my_addr_len = sizeof(my_addr);
115
116	if (getsockname(admin_fd, (struct sockaddr *)&my_addr,
117	&my_addr_len) < 0) {
118	status = errno;
119	goto punt;
120	}
121
122	if (ioctl(admin_fd, FIONBIO, (char *)&on) < 0) {
123	status = errno;
124	goto punt;
125	}
126
127	inited = 1;
128	}
129	return 0;
130
131	punt:
132	(void) close(admin_fd);
133	admin_fd = -1;
134	return status;
135	}
136
137	/*
138	* Build and transmit request to admin_server, and wait for
139	* response from server. Returns a standard error code.
140	*/
141
142	int
143	admin_call(opcode, pname, old_passwd, new_passwd, crypt_passwd)
144	int opcode;
145	char *pname;
146	char *old_passwd;
147	char *new_passwd;
148	char *crypt_passwd;
149	{
150	int status;
151	register u_char bp; / Pointer into buffer. */
152	u_char ep; / End of buffer pointer. */
153
154	u_char pvt_buf[BUFSIZ]; /* private message plaintext */
155	int pvt_len; /* length of valid data in pvt_buf */
156
157	u_char sealed_buf[BUFSIZ]; /* sealed version of private message */
158	int sealed_len; /* length of valid data in sealed_buf */
159
160	u_long checksum; /* quad_cksum of sealed request. */
161
162	C_Block sess_key; /* Session key. */
163	Key_schedule sess_sched; /* Key schedule for above. */
164
165	CREDENTIALS cred; /* Kerberos credentials. */
166	KTEXT_ST authent; /* Authenticator */
167	KTEXT_ST reply; /* Reply from admin_server */
168	MSG_DAT msg_data; /* Decrypted message */
169	int attempts; /* Number of retransmits so far */
170
171	struct sockaddr rec_addr; /* Address we got reply from */
172	int rec_addr_len; /* Length of that address */
173
174	if (!inited) {
175	status = admin_call_init();
176	if (status) goto bad;
177	}
178
179	/*
180	* assemble packet:
181	*
182	* sealed message consists of:
183	* version number (one byte).
184	* request code (one byte).
185	* principal name (null terminated).
186	* new password (in the clear, null terminated).
187	* old password or instance (null terminated)
188	* crypt(new password, seed) (null terminated).
189	* an extra null.
190	* a '\001' character.
191	* This is all sealed inside a private_message, with an
192	* authenticator tacked on in front.
193	*/
194
195	bp = pvt_buf;
196	ep = pvt_buf + sizeof(pvt_buf);
197
198	*bp++ = PW_SRV_VERSION;
199	*bp++ = opcode;
200	if ((bp = strapp(bp, (u_char *)pname, ep)) &&
201	(bp = strapp(bp, (u_char *)new_passwd, ep)) &&
202	(bp = strapp(bp, (u_char *)old_passwd, ep)) &&
203	(bp = strapp(bp, (u_char *)crypt_passwd, ep))) {
204	*bp++ = '\0';
205	*bp++ = '\1';
206	pvt_len = bp - pvt_buf;
207	} else {
208	status = ADMIN_TOO_LONG;
209	goto bad;
210	}
211
212	/*
213	* find our session key.
214	*/
215
216	if (status = get_credentials("changepw", "kerberos", krbrlm, &cred)) {
217	status += krb_err_base;
218	goto bad;
219	}
220
221	bcopy((char )cred.session, (char )sess_key, sizeof(sess_key));
222	bzero((char )cred.session, sizeof(sess_key)); / lest we remember */
223
224	if(key_sched(sess_key, sess_sched)) {
225	status = ADMIN_BAD_KEY;
226	goto bad;
227	}
228
229	/*
230	* Encrypt the message using the session key.
231	* Since this contains passwords, it must be kept from prying eyes.
232	*/
233
234	sealed_len = mk_private_msg(pvt_buf, sealed_buf, pvt_len,
235	sess_sched, sess_key, &my_addr,
236	&admin_addr);
237	if (sealed_len < 0) {
238	status = ADMIN_CANT_ENCRYPT;
239	goto bad;
240	}
241
242	/*
243	* Checksum the cypher text, to guard against tampering in flight.
244	*/
245
246	checksum = quad_cksum(sealed_buf, NULL, sealed_len, 0, sess_key);
247
248	/*
249	* Make an authenticator, so the server can learn the session key
250	* and know who we are.
251	*/
252
253	if (status = mk_ap_req(&authent, "changepw", "kerberos", krbrlm,
254	checksum)) {
255	status += krb_err_base;
256	goto bad;
257	}
258
259	/*
260	* Add the sealed message to the end of the authenticator.
261	*/
262
263	if ((authent.length + sealed_len) > MAX_KTXT_LEN) {
264	status = ADMIN_TOO_LONG;
265	goto bad;
266	}
267
268	bcopy(sealed_buf, authent.dat + authent.length, sealed_len);
269	authent.length += sealed_len;
270
271	/*
272	* send it off, and wait for a reply.
273	*/
274
275	attempts = 0;
276
277	while (attempts++ < RETRY_LIMIT) {
278	int active; /* number of active fds (from select). */
279	fd_set set; /* interesting fd's. */
280	struct timeval timeout; /* timeout on select. */
281
282	if (sendto(admin_fd, (char *)authent.dat, authent.length,
283	0, &admin_addr, sizeof(admin_addr)) != authent.length) {
284	status = errno;
285	goto bad;
286	}
287
288	FD_ZERO(&set);
289	FD_SET(admin_fd, &set);
290
291	timeout.tv_sec = USER_TIMEOUT;
292	timeout.tv_usec = 0;
293
294	active = select(admin_fd+1, &set, (fd_set )0, (fd_set )0, &timeout);
295	if (active < 0) {
296	status = errno;
297	goto bad;
298	} else if (active == 0) continue;
299	else {
300	reply.length = recvfrom(admin_fd, (char *)reply.dat,
301	sizeof(reply.dat), 0,
302	&rec_addr, &rec_addr_len);
303	if (reply.length < 0) continue;
304	#ifdef notdef
305	if (!bcmp(&rec_addr, &admin_addr, sizeof(admin_addr)))
306	/* the spoofers are out in force.. */
307	continue;
308	#endif notdef
309	break; /* got one.. */
310	}
311	}
312
313	if (attempts > RETRY_LIMIT) {
314	status = ETIMEDOUT;
315	goto bad;
316	}
317
318	if (pkt_version((&reply)) != KRB_PROT_VERSION) {
319	status = ADMIN_BAD_VERSION;
320	goto bad;
321	}
322
323	if ((pkt_msg_type((&reply)) & ~1) != AUTH_MSG_PRIVATE) {
324	bp = reply.dat;
325	if (*bp++ != KRB_PROT_VERSION) {
326	status = ADMIN_BAD_VERSION;
327	goto bad;
328	}
329	if (*bp++ != AUTH_MSG_ERR_REPLY) {
330	status = ADMIN_UNKNOWN_CODE;
331	goto bad;
332	}
333	bp += strlen((char )bp) + 1; / Skip name */
334	bp += strlen((char )bp) + 1; / Skip instance */
335	bp += strlen((char )bp) + 1; / Skip realm */
336
337	/* null-terminate error string */
338	reply.dat[reply.length] = '\0';
339
340	if (*bp++ == 126) {
341	status = ADMIN_SERVER_ERROR;
342	strcpy(admin_errmsg, bp);
343	goto bad;
344	} else {
345	status = ADMIN_UNKNOWN_CODE;
346	goto bad;
347	}
348	}
349	status = rd_private_msg(reply.dat, reply.length,
350	sess_sched, sess_key,
351	&admin_addr, &my_addr,
352	&msg_data);
353	if (status) {
354	status += krb_err_base;
355	goto bad;
356	}
357	bp = msg_data.app_data;
358
359	if (*bp++ != PW_SRV_VERSION) {
360	status = ADMIN_BAD_VERSION;
361	goto bad;
362	}
363	if (*bp++ != INSTALL_REPLY) {
364	status = ADMIN_UNKNOWN_CODE;
365	goto bad;
366	}
367
368	status = 0;
369	/* fall through into cleanup */
370
371	bad:
372	/*
373	* Paranoia: shred all the incriminating evidence.
374	* We'll let the caller shred the arguments.
375	*/
376	bzero((char *)sess_key, sizeof(sess_key));
377	bzero((char *)sess_sched, sizeof(sess_sched));
378	bzero(pvt_buf, sizeof(pvt_buf));
379	return status;
380	}
381
382	/*
383	* Copies characters from source to dest, returning a pointer to the
384	* point in dest after the last character copied from source.
385	* If this would be greater than end, no characters are copied, and NULL
386	* is returned instead.
387	*/
388
389	static u_char *strapp(dest, source, end)
390	register u_char dest, source, *end;
391	{
392	register int length = strlen(source) + 1;
393	if (dest+length > end) return NULL;
394	else {
395	bcopy(source, dest, length);
396	return dest + length;
397	}
398	}
399
400	/*
401	* Local Variables:
402	* mode: c
403	* c-indent-level: 4
404	* c-continued-statement-offset: 4
405	* c-brace-offset: -4
406	* c-argdecl-indent: 4
407	* c-label-offset: -4
408	* End:
409	*/