1 /*
2  * Copyright 2001-2003 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 #pragma ident	"%Z%%M%	%I%	%E% SMI"
7 
8 #include <stdio.h>
9 #include <string.h>
10 #include "lber.h"
11 #include "ldap.h"
12 #include "ldap-int.h"
13 #include <sys/types.h>
14 #include <strings.h>
15 #include "sec.h"
16 
17 /* text is the challenge, key is the password, digest is an allocated
18    buffer (min 16 chars) which will contain the resulting digest */
19 void hmac_md5(unsigned char *text, int text_len, unsigned char *key,
20 	int key_len, unsigned char *digest)
21 {
22 	MD5_CTX context;
23 	unsigned char k_ipad[65];
24 	unsigned char k_opad[65];
25 	unsigned char tk[16];
26 	int i;
27 
28 	if (key_len > 64){
29 		MD5_CTX tctx;
30 
31 		(void) MD5Init(&tctx);
32 		(void) MD5Update(&tctx, key, key_len);
33 		(void) MD5Final(tk, &tctx);
34 		key = tk;
35 		key_len = 16;
36 	}
37 
38 	bzero(k_ipad, sizeof (k_ipad));
39 	bzero(k_opad, sizeof (k_opad));
40 	bcopy(key, k_ipad, key_len);
41 	bcopy(key, k_opad, key_len);
42 
43 	for (i=0; i<64; i++){
44 		k_ipad[i] ^= 0x36;
45 		k_opad[i] ^= 0x5c;
46 	}
47 
48 	/* Perform inner MD5 */
49 	(void) MD5Init(&context);
50 	(void) MD5Update(&context, k_ipad, 64);
51 	(void) MD5Update(&context, text, text_len);
52 	(void) MD5Final(digest, &context);
53 
54 	/* Perform outer MD5 */
55 	(void) MD5Init(&context);
56 	(void) MD5Update(&context, k_opad, 64);
57 	(void) MD5Update(&context, digest, 16);
58 
59 	(void) MD5Final(digest, &context);
60 
61 	return;
62 }
63 
64 int ldap_sasl_cram_md5_bind_s(
65 	LDAP *ld,
66 	char *dn,
67 	struct berval *cred,
68 	LDAPControl **serverctrls,
69 	LDAPControl **clientctrls )
70 {
71 	int res;
72 	struct berval *challenge = NULL;
73 	struct berval resp;
74 	unsigned char digest[16];
75 	char *theHDigest;
76 
77 	if (dn == NULL){
78 		return (LDAP_PARAM_ERROR);
79 	}
80 
81 	bzero(digest, sizeof (digest));
82 
83 	if ((res = ldap_sasl_bind_s(ld, NULL, LDAP_SASL_CRAM_MD5, NULL, serverctrls, clientctrls, &challenge))
84 		!= LDAP_SASL_BIND_IN_PROGRESS){
85 		return (res);
86 	}
87 	if (challenge == NULL){
88 		return (LDAP_PARAM_ERROR);
89 	}
90 
91 	LDAPDebug (LDAP_DEBUG_TRACE, "SASL challenge: %s\n", challenge->bv_val, 0, 0);
92 
93 	hmac_md5((unsigned char *)challenge->bv_val, challenge->bv_len,
94 					 (unsigned char *)cred->bv_val, cred->bv_len,  digest);
95 	ber_bvfree(challenge);
96 	challenge = NULL;
97 
98 	theHDigest = hexa_print(digest, 16);
99 	if (theHDigest == NULL){
100 		return (LDAP_NO_MEMORY);
101 	}
102 
103 	resp.bv_len = (strlen(dn) + 32 + 1);
104 	if ((resp.bv_val = (char *)malloc(resp.bv_len+1)) == NULL) {
105 		return(LDAP_NO_MEMORY);
106 	}
107 
108 	sprintf(resp.bv_val, "%s %s", dn, theHDigest);
109 	free(theHDigest);
110 
111 	LDAPDebug (LDAP_DEBUG_TRACE, "SASL response: %s\n", resp.bv_val, 0, 0);
112 	res = ldap_sasl_bind_s(ld, NULL, LDAP_SASL_CRAM_MD5, &resp, serverctrls, clientctrls, &challenge);
113 
114 	free(resp.bv_val);
115 	return (res);
116 }
117