Towards RFC 1938 compliance. Also, now supports SHA (secure hash algorithm).

1 files changed, 105 insertions, 49 deletions

diff --git a/lib/libskey/skeysubr.c b/lib/libskey/skeysubr.c
index 6c3f9ea985a..8907592c62f 100644
--- a/lib/libskey/skeysubr.c
+++ b/lib/libskey/skeysubr.c
@@ -10,7 +10,7 @@
  *
  * S/KEY misc routines.
  *
- * $Id: skeysubr.c,v 1.3 1996/09/27 20:40:17 millert Exp $
+ * $Id: skeysubr.c,v 1.4 1996/09/29 21:27:02 millert Exp $
  */
 
 #include <stdio.h>
@@ -20,22 +20,43 @@
 #include <termios.h>
 #include <md4.h>
 #include <md5.h>
+#include <sha1.h>
 
 #include "skey.h"
 
-/* Default MDX function to use (currently 4 or 5) */
-#ifndef SKEY_MDX_DEFAULT
-#define SKEY_MDX_DEFAULT	5
+/* Default hash function to use (index into skey_hash_types array) */
+#ifndef SKEY_HASH_DEFAULT
+#define SKEY_HASH_DEFAULT	1
 #endif
 
 static void trapped __ARGS((int sig));
-static void f_MD4 __ARGS ((char *x));
-static void f_MD5 __ARGS ((char *x));
-static void skey_echo __ARGS ((int));
-static int keycrunch_MD4 __ARGS ((char *result, char *seed, char *passwd));
-static int keycrunch_MD5 __ARGS ((char *result, char *seed, char *passwd));
+static void f_md4 __ARGS ((char *x));
+static void f_md5 __ARGS ((char *x));
+static void f_sha1 __ARGS ((char *x));
+static void skey_echo __ARGS ((int action));
+static int keycrunch_md4 __ARGS ((char *result, char *seed, char *passwd));
+static int keycrunch_md5 __ARGS ((char *result, char *seed, char *passwd));
+static int keycrunch_sha1 __ARGS ((char *result, char *seed, char *passwd));
+
+/* Current hash type (index into skey_hash_types array) */
+static int skey_hash_type = SKEY_HASH_DEFAULT;
+
+/*
+ * Hash types we support.
+ * Each has an associated keycrunch() and f() function.
+ */
+#define SKEY_ALGORITH_MAX	3
+struct skey_algorithm_table {
+	const char *name;
+	int (*keycrunch) __ARGS((char *, char *, char *));
+	void (*f) __ARGS((char *));
+};
+static struct skey_algorithm_table skey_algorithm_table[] = {
+	{ "md4", keycrunch_md4, f_md4 },
+	{ "md5", keycrunch_md5, f_md5 },
+	{ "sha1", keycrunch_sha1, f_sha1 }
+};
 
-static int skey_MDX = 0;
 
 /*
  * Crunch a key:
@@ -48,19 +69,11 @@ keycrunch(result, seed, passwd)
 	char *seed;	/* Seed, any length */
 	char *passwd;	/* Password, any length */
 {
-	switch (skey_get_MDX()) {
-		/*
-		 * Need a default case to appease gc even though 
-		 * skey_set_MDX() guantaees we get back 4 or 5
-		 */
-		case 4  : return(keycrunch_MD4(result, seed, passwd));
-		default : return(keycrunch_MD5(result, seed, passwd));
-	}
-	/* NOTREACHED */
+	return(skey_algorithm_table[skey_hash_type].keycrunch(result, seed, passwd));
 }
 
 static int
-keycrunch_MD4(result, seed, passwd)
+keycrunch_md4(result, seed, passwd)
 	char *result;	/* 8-byte result */
 	char *seed;	/* Seed, any length */
 	char *passwd;	/* Password, any length */
@@ -93,7 +106,7 @@ keycrunch_MD4(result, seed, passwd)
 }
 
 static int
-keycrunch_MD5(result, seed, passwd)
+keycrunch_md5(result, seed, passwd)
 	char *result;	/* 8-byte result */
 	char *seed;	/* Seed, any length */
 	char *passwd;	/* Password, any length */
@@ -125,24 +138,49 @@ keycrunch_MD5(result, seed, passwd)
 	return 0;
 }
 
+static int
+keycrunch_sha1(result, seed, passwd)
+	char *result;	/* 8-byte result */
+	char *seed;	/* Seed, any length */
+	char *passwd;	/* Password, any length */
+{
+	char *buf;
+	SHA1_INFO sha;
+	unsigned int buflen;
+
+	buflen = strlen(seed) + strlen(passwd);
+	if ((buf = (char *)malloc(buflen+1)) == NULL)
+		return -1;
+	(void)strcpy(buf, seed);
+	(void)strcat(buf, passwd);
+
+	/* Crunch the key through SHA1 */
+	sevenbit(buf);
+	sha1Init(&sha);
+	sha1Update(&sha, (unsigned char *)buf, buflen);
+	sha1Final(&sha);
+	(void)free(buf);
+
+	/* Fold 160 to 64 bits */
+	sha.digest[0] ^= sha.digest[2];
+	sha.digest[1] ^= sha.digest[3];
+	sha.digest[0] ^= sha.digest[4];
+
+	(void)memcpy((void *)result, (void *)sha.digest, 8);
+
+	return 0;
+}
+
 /* The one-way function f(). Takes 8 bytes and returns 8 bytes in place */
 void
 f(x)
 	char *x;
 {
-	switch (skey_get_MDX()) {
-		/*
-		 * Need a default case to appease gc even though 
-		 * skey_set_MDX() guantaees we get back 4 or 5
-		 */
-		case 4  : return(f_MD4(x));
-		default : return(f_MD5(x));
-	}
-	/* NOTREACHED */
+	skey_algorithm_table[skey_hash_type].f(x);
 }
 
 void
-f_MD4(x)
+f_md4(x)
 	char *x;
 {
 	MD4_CTX md;
@@ -160,7 +198,7 @@ f_MD4(x)
 }
 
 void
-f_MD5(x)
+f_md5(x)
 	char *x;
 {
 	MD5_CTX md;
@@ -177,6 +215,24 @@ f_MD5(x)
 	(void)memcpy((void *)x, (void *)results, 8);
 }
 
+void
+f_sha1(x)
+	char *x;
+{
+	SHA1_INFO sha;
+
+	sha1Init(&sha);
+	sha1Update(&sha, (unsigned char *)x, 8);
+	sha1Final(&sha);
+
+	/* Fold 160 to 64 bits */
+	sha.digest[0] ^= sha.digest[2];
+	sha.digest[1] ^= sha.digest[3];
+	sha.digest[0] ^= sha.digest[4];
+
+	(void)memcpy((void *)x, (void *)sha.digest, 8);
+}
+
 /* Strip trailing cr/lf from a line of text */
 void
 rip(buf)
@@ -359,29 +415,29 @@ sevenbit(s)
 		*s++ &= 0x7f;
 }
 
-/* Set MDX type (returns previous) */
-int
-skey_set_MDX(new)
-	int new;
+/* Set hash type type */
+char *
+skey_set_algorithm(new)
+	char *new;
 {
-	int old;
+	int i;
 
-	if (new != 4 && new != 5)
-		return -1;
+	for (i = 0; i < SKEY_ALGORITH_MAX; i++) {
+		/* XXX - should be case *sensitive* */
+		if (strcasecmp(new, skey_algorithm_table[i].name) == 0) {
+			skey_hash_type = i;
+			return(new);
+		}
+	}
 
-	old = skey_get_MDX();
-	skey_MDX = new;
-	return old;
+	return(NULL);
 }
 
-/* Get current MDX type */
-int
-skey_get_MDX()
+/* Get current hash type */
+const char *
+skey_get_algorithm()
 {
-	if (skey_MDX == 0)
-		skey_MDX = SKEY_MDX_DEFAULT;
-
-	return skey_MDX;
+	return(skey_algorithm_table[skey_hash_type].name);
 }
 
 /* Turn echo on/off */