[openssh.git] / auth-skey.c

#include "includes.h"

#ifdef SKEY

RCSID("$Id$");

#include "ssh.h"
#include <sha1.h>

/* from %OpenBSD: skeylogin.c,v 1.32 1999/08/16 14:46:56 millert Exp % */


#define ROUND(x)   (((x)[0] << 24) + (((x)[1]) << 16) + (((x)[2]) << 8) + \
		    ((x)[3]))

/*
 * hash_collapse()
 */
static u_int32_t
hash_collapse(s)
        u_char *s;
{
        int len, target;
	u_int32_t i;
	
	if ((strlen(s) % sizeof(u_int32_t)) == 0)
  		target = strlen(s);    /* Multiple of 4 */
	else
		target = strlen(s) - (strlen(s) % sizeof(u_int32_t));
  
	for (i = 0, len = 0; len < target; len += 4)
        	i ^= ROUND(s + len);

	return i;
}

char *
skey_fake_keyinfo(char *username)
{
	int i;
	u_int ptr;
	u_char hseed[SKEY_MAX_SEED_LEN], flg = 1, *up;
	char pbuf[SKEY_MAX_PW_LEN+1];
	static char skeyprompt[SKEY_MAX_CHALLENGE+1];
	char *secret = NULL;
	size_t secretlen = 0;
	SHA1_CTX ctx;
	char *p, *u;

	/*
	 * Base first 4 chars of seed on hostname.
	 * Add some filler for short hostnames if necessary.
	 */
	if (gethostname(pbuf, sizeof(pbuf)) == -1)
		*(p = pbuf) = '.';
	else
		for (p = pbuf; *p && isalnum(*p); p++)
			if (isalpha(*p) && isupper(*p))
				*p = tolower(*p);
	if (*p && pbuf - p < 4)
		(void)strncpy(p, "asjd", 4 - (pbuf - p));
	pbuf[4] = '\0';

	/* Hash the username if possible */
	if ((up = SHA1Data(username, strlen(username), NULL)) != NULL) {
		struct stat sb;
		time_t t;
		int fd;

		/* Collapse the hash */
		ptr = hash_collapse(up);
		memset(up, 0, strlen(up));

		/* See if the random file's there, else use ctime */
		if ((fd = open(_SKEY_RAND_FILE_PATH_, O_RDONLY)) != -1
		    && fstat(fd, &sb) == 0 &&
		    sb.st_size > (off_t)SKEY_MAX_SEED_LEN &&
		    lseek(fd, ptr % (sb.st_size - SKEY_MAX_SEED_LEN),
		    SEEK_SET) != -1 && read(fd, hseed,
		    SKEY_MAX_SEED_LEN) == SKEY_MAX_SEED_LEN) {
			close(fd);
			secret = hseed;
			secretlen = SKEY_MAX_SEED_LEN;
			flg = 0;
		} else if (!stat(_PATH_MEM, &sb) || !stat("/", &sb)) {
			t = sb.st_ctime;
			secret = ctime(&t);
			secretlen = strlen(secret);
			flg = 0;
		}
	}

	/* Put that in your pipe and smoke it */
	if (flg == 0) {
		/* Hash secret value with username */
		SHA1Init(&ctx);
		SHA1Update(&ctx, secret, secretlen);
		SHA1Update(&ctx, username, strlen(username));
		SHA1End(&ctx, up);
		
		/* Zero out */
		memset(secret, 0, secretlen);

		/* Now hash the hash */
		SHA1Init(&ctx);
		SHA1Update(&ctx, up, strlen(up));
		SHA1End(&ctx, up);
		
		ptr = hash_collapse(up + 4);
		
		for (i = 4; i < 9; i++) {
			pbuf[i] = (ptr % 10) + '0';
			ptr /= 10;
		}
		pbuf[i] = '\0';

		/* Sequence number */
		ptr = ((up[2] + up[3]) % 99) + 1;

		memset(up, 0, 20); /* SHA1 specific */
		free(up);

		(void)snprintf(skeyprompt, sizeof skeyprompt,
			      "otp-%.*s %d %.*s",
			      SKEY_MAX_HASHNAME_LEN,
			      skey_get_algorithm(),
			      ptr, SKEY_MAX_SEED_LEN,
			      pbuf);
	} else {
		/* Base last 8 chars of seed on username */
		u = username;
		i = 8;
		p = &pbuf[4];
		do {
			if (*u == 0) {
				/* Pad remainder with zeros */
				while (--i >= 0)
					*p++ = '0';
				break;
			}

			*p++ = (*u++ % 10) + '0';
		} while (--i != 0);
		pbuf[12] = '\0';

		(void)snprintf(skeyprompt, sizeof skeyprompt,
			      "otp-%.*s %d %.*s",
			      SKEY_MAX_HASHNAME_LEN,
			      skey_get_algorithm(),
			      99, SKEY_MAX_SEED_LEN, pbuf);
	}
	return skeyprompt;
}

#endif /* SKEY */
Commit	Line	Data
5260325f	1	#include "includes.h"
5260325f	2
91b8065d	3	#ifdef SKEY
91b8065d	4
8efc0c15	5	RCSID("$Id$");
	6
	7	#include "ssh.h"
	8	#include <sha1.h>
	9
	10	/* from %OpenBSD: skeylogin.c,v 1.32 1999/08/16 14:46:56 millert Exp % */
	11
	12
	13	#define ROUND(x) (((x)[0] << 24) + (((x)[1]) << 16) + (((x)[2]) << 8) + \
	14	((x)[3]))
	15
	16	/*
	17	* hash_collapse()
	18	*/
	19	static u_int32_t
	20	hash_collapse(s)
	21	u_char *s;
	22	{
	23	int len, target;
	24	u_int32_t i;
	25
	26	if ((strlen(s) % sizeof(u_int32_t)) == 0)
	27	target = strlen(s); /* Multiple of 4 */
	28	else
	29	target = strlen(s) - (strlen(s) % sizeof(u_int32_t));
	30
	31	for (i = 0, len = 0; len < target; len += 4)
	32	i ^= ROUND(s + len);
	33
	34	return i;
	35	}
5260325f	36
8efc0c15	37	char *
	38	skey_fake_keyinfo(char *username)
	39	{
	40	int i;
	41	u_int ptr;
	42	u_char hseed[SKEY_MAX_SEED_LEN], flg = 1, *up;
	43	char pbuf[SKEY_MAX_PW_LEN+1];
	44	static char skeyprompt[SKEY_MAX_CHALLENGE+1];
	45	char *secret = NULL;
	46	size_t secretlen = 0;
	47	SHA1_CTX ctx;
	48	char p, u;
	49
	50	/*
	51	* Base first 4 chars of seed on hostname.
	52	* Add some filler for short hostnames if necessary.
	53	*/
	54	if (gethostname(pbuf, sizeof(pbuf)) == -1)
	55	*(p = pbuf) = '.';
	56	else
	57	for (p = pbuf; p && isalnum(p); p++)
	58	if (isalpha(p) && isupper(p))
	59	p = tolower(p);
	60	if (*p && pbuf - p < 4)
	61	(void)strncpy(p, "asjd", 4 - (pbuf - p));
	62	pbuf[4] = '\0';
	63
	64	/* Hash the username if possible */
	65	if ((up = SHA1Data(username, strlen(username), NULL)) != NULL) {
	66	struct stat sb;
	67	time_t t;
	68	int fd;
	69
	70	/* Collapse the hash */
	71	ptr = hash_collapse(up);
	72	memset(up, 0, strlen(up));
	73
	74	/* See if the random file's there, else use ctime */
	75	if ((fd = open(_SKEY_RAND_FILE_PATH_, O_RDONLY)) != -1
	76	&& fstat(fd, &sb) == 0 &&
	77	sb.st_size > (off_t)SKEY_MAX_SEED_LEN &&
	78	lseek(fd, ptr % (sb.st_size - SKEY_MAX_SEED_LEN),
	79	SEEK_SET) != -1 && read(fd, hseed,
	80	SKEY_MAX_SEED_LEN) == SKEY_MAX_SEED_LEN) {
	81	close(fd);
	82	secret = hseed;
	83	secretlen = SKEY_MAX_SEED_LEN;
	84	flg = 0;
	85	} else if (!stat(_PATH_MEM, &sb) \|\| !stat("/", &sb)) {
	86	t = sb.st_ctime;
	87	secret = ctime(&t);
	88	secretlen = strlen(secret);
	89	flg = 0;
	90	}
	91	}
	92
	93	/* Put that in your pipe and smoke it */
	94	if (flg == 0) {
	95	/* Hash secret value with username */
	96	SHA1Init(&ctx);
	97	SHA1Update(&ctx, secret, secretlen);
	98	SHA1Update(&ctx, username, strlen(username));
	99	SHA1End(&ctx, up);
	100
101	/* Zero out */
102	memset(secret, 0, secretlen);
103
104	/* Now hash the hash */
105	SHA1Init(&ctx);
106	SHA1Update(&ctx, up, strlen(up));
107	SHA1End(&ctx, up);
108
109	ptr = hash_collapse(up + 4);
110
111	for (i = 4; i < 9; i++) {
112	pbuf[i] = (ptr % 10) + '0';
113	ptr /= 10;
114	}
115	pbuf[i] = '\0';
116
117	/* Sequence number */
118	ptr = ((up[2] + up[3]) % 99) + 1;
119
120	memset(up, 0, 20); /* SHA1 specific */
121	free(up);
122
123	(void)snprintf(skeyprompt, sizeof skeyprompt,
124	"otp-%.s %d %.s",
125	SKEY_MAX_HASHNAME_LEN,
126	skey_get_algorithm(),
127	ptr, SKEY_MAX_SEED_LEN,
128	pbuf);
129	} else {
130	/* Base last 8 chars of seed on username */
131	u = username;
132	i = 8;
133	p = &pbuf[4];
134	do {
135	if (*u == 0) {
136	/* Pad remainder with zeros */
137	while (--i >= 0)
138	*p++ = '0';
139	break;
140	}
141
142	p++ = (u++ % 10) + '0';
143	} while (--i != 0);
144	pbuf[12] = '\0';
145
146	(void)snprintf(skeyprompt, sizeof skeyprompt,
147	"otp-%.s %d %.s",
148	SKEY_MAX_HASHNAME_LEN,
149	skey_get_algorithm(),
150	99, SKEY_MAX_SEED_LEN, pbuf);
151	}
152	return skeyprompt;
153	}
91b8065d	154
5260325f	155	#endif /* SKEY */