1 files changed, 139 insertions, 0 deletions
diff --git a/lib/libcrypt/crypt-md5.c b/lib/libcrypt/crypt-md5.c
new file mode 100644
index 0000000..49710d6
--- /dev/null
+++ b/lib/libcrypt/crypt-md5.c
@@ -0,0 +1,139 @@
+/*
+ * ----------------------------------------------------------------------------
+ * "THE BEER-WARE LICENSE" (Revision 42):
+ * <phk@FreeBSD.org> wrote this file.  As long as you retain this notice you
+ * can do whatever you want with this stuff. If we meet some day, and you think
+ * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
+ * ----------------------------------------------------------------------------
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <unistd.h>
+#include <stdio.h>
+#include <string.h>
+#include <md5.h>
+#include <err.h>
+#include "crypt.h"
+
+/*
+ * UNIX password
+ */
+
+char *
+crypt_md5(const char *pw, const char *salt)
+{
+	MD5_CTX	ctx,ctx1;
+	unsigned long l;
+	int sl, pl;
+	u_int i;
+	u_char final[MD5_SIZE];
+	static const char *sp, *ep;
+	static char passwd[120], *p;
+	static const char *magic = "$1$";	/*
+						 * This string is magic for
+						 * this algorithm.  Having
+						 * it this way, we can get
+						 * better later on.
+						 */
+
+	/* Refine the Salt first */
+	sp = salt;
+
+	/* If it starts with the magic string, then skip that */
+	if(!strncmp(sp, magic, strlen(magic)))
+		sp += strlen(magic);
+
+	/* It stops at the first '$', max 8 chars */
+	for(ep = sp; *ep && *ep != '$' && ep < (sp + 8); ep++)
+		continue;
+
+	/* get the length of the true salt */
+	sl = ep - sp;
+
+	MD5Init(&ctx);
+
+	/* The password first, since that is what is most unknown */
+	MD5Update(&ctx, (const u_char *)pw, strlen(pw));
+
+	/* Then our magic string */
+	MD5Update(&ctx, (const u_char *)magic, strlen(magic));
+
+	/* Then the raw salt */
+	MD5Update(&ctx, (const u_char *)sp, (u_int)sl);
+
+	/* Then just as many characters of the MD5(pw,salt,pw) */
+	MD5Init(&ctx1);
+	MD5Update(&ctx1, (const u_char *)pw, strlen(pw));
+	MD5Update(&ctx1, (const u_char *)sp, (u_int)sl);
+	MD5Update(&ctx1, (const u_char *)pw, strlen(pw));
+	MD5Final(final, &ctx1);
+	for(pl = (int)strlen(pw); pl > 0; pl -= MD5_SIZE)
+		MD5Update(&ctx, (const u_char *)final,
+		    (u_int)(pl > MD5_SIZE ? MD5_SIZE : pl));
+
+	/* Don't leave anything around in vm they could use. */
+	memset(final, 0, sizeof(final));
+
+	/* Then something really weird... */
+	for (i = strlen(pw); i; i >>= 1)
+		if(i & 1)
+		    MD5Update(&ctx, (const u_char *)final, 1);
+		else
+		    MD5Update(&ctx, (const u_char *)pw, 1);
+
+	/* Now make the output string */
+	strcpy(passwd, magic);
+	strncat(passwd, sp, (u_int)sl);
+	strcat(passwd, "$");
+
+	MD5Final(final, &ctx);
+
+	/*
+	 * and now, just to make sure things don't run too fast
+	 * On a 60 Mhz Pentium this takes 34 msec, so you would
+	 * need 30 seconds to build a 1000 entry dictionary...
+	 */
+	for(i = 0; i < 1000; i++) {
+		MD5Init(&ctx1);
+		if(i & 1)
+			MD5Update(&ctx1, (const u_char *)pw, strlen(pw));
+		else
+			MD5Update(&ctx1, (const u_char *)final, MD5_SIZE);
+
+		if(i % 3)
+			MD5Update(&ctx1, (const u_char *)sp, (u_int)sl);
+
+		if(i % 7)
+			MD5Update(&ctx1, (const u_char *)pw, strlen(pw));
+
+		if(i & 1)
+			MD5Update(&ctx1, (const u_char *)final, MD5_SIZE);
+		else
+			MD5Update(&ctx1, (const u_char *)pw, strlen(pw));
+		MD5Final(final, &ctx1);
+	}
+
+	p = passwd + strlen(passwd);
+
+	l = (final[ 0]<<16) | (final[ 6]<<8) | final[12];
+	_crypt_to64(p, l, 4); p += 4;
+	l = (final[ 1]<<16) | (final[ 7]<<8) | final[13];
+	_crypt_to64(p, l, 4); p += 4;
+	l = (final[ 2]<<16) | (final[ 8]<<8) | final[14];
+	_crypt_to64(p, l, 4); p += 4;
+	l = (final[ 3]<<16) | (final[ 9]<<8) | final[15];
+	_crypt_to64(p, l, 4); p += 4;
+	l = (final[ 4]<<16) | (final[10]<<8) | final[ 5];
+	_crypt_to64(p, l, 4); p += 4;
+	l =                    final[11]                ;
+	_crypt_to64(p, l, 2); p += 2;
+	*p = '\0';
+
+	/* Don't leave anything around in vm they could use. */
+	memset(final, 0, sizeof(final));
+
+	return passwd;
+}
+