Added EAP support with MD5-Challenge and SRP-SHA1 methods. Tested

[ppp.git] / pppd / pppcrypt.c

diff --git a/pppd/pppcrypt.c b/pppd/pppcrypt.c
new file mode 100644 (file)
index 0000000..1c4ce3b
--- /dev/null
+++ b/pppd/pppcrypt.c
@@ -0,0 +1,185 @@
+/*
+ * pppcrypt.c - PPP/DES linkage for MS-CHAP and EAP SRP-SHA1
+ *
+ * Extracted from chap_ms.c by James Carlson.
+ *
+ * Copyright (c) 1995 Eric Rosenquist, Strata Software Limited.
+ * http://www.strataware.com/
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by Eric Rosenquist.  The name of the author may not be used to
+ * endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+#include <errno.h>
+#include "pppd.h"
+#include "pppcrypt.h"
+
+static u_char
+Get7Bits(input, startBit)
+u_char *input;
+int startBit;
+{
+       unsigned int word;
+
+       word  = (unsigned)input[startBit / 8] << 8;
+       word |= (unsigned)input[startBit / 8 + 1];
+
+       word >>= 15 - (startBit % 8 + 7);
+
+       return word & 0xFE;
+}
+
+static void
+MakeKey(key, des_key)
+u_char *key;           /* IN  56 bit DES key missing parity bits */
+u_char *des_key;       /* OUT 64 bit DES key with parity bits added */
+{
+       des_key[0] = Get7Bits(key,  0);
+       des_key[1] = Get7Bits(key,  7);
+       des_key[2] = Get7Bits(key, 14);
+       des_key[3] = Get7Bits(key, 21);
+       des_key[4] = Get7Bits(key, 28);
+       des_key[5] = Get7Bits(key, 35);
+       des_key[6] = Get7Bits(key, 42);
+       des_key[7] = Get7Bits(key, 49);
+
+#ifndef USE_CRYPT
+       des_set_odd_parity((des_cblock *)des_key);
+#endif
+}
+
+#ifdef USE_CRYPT
+/*
+ * in == 8-byte string (expanded version of the 56-bit key)
+ * out == 64-byte string where each byte is either 1 or 0
+ * Note that the low-order "bit" is always ignored by by setkey()
+ */
+static void
+Expand(in, out)
+u_char *in;
+u_char *out;
+{
+        int j, c;
+        int i;
+
+        for (i = 0; i < 64; in++){
+               c = *in;
+                for (j = 7; j >= 0; j--)
+                        *out++ = (c >> j) & 01;
+                i += 8;
+        }
+}
+
+/* The inverse of Expand
+ */
+static void
+Collapse(in, out)
+u_char *in;
+u_char *out;
+{
+        int j;
+        int i;
+       unsigned int c;
+
+       for (i = 0; i < 64; i += 8, out++) {
+           c = 0;
+           for (j = 7; j >= 0; j--, in++)
+               c |= *in << j;
+           *out = c & 0xff;
+       }
+}
+
+bool
+DesSetkey(key)
+u_char *key;
+{
+       u_char des_key[8];
+       u_char crypt_key[66];
+
+       MakeKey(key, des_key);
+       Expand(des_key, crypt_key);
+       errno = 0;
+       setkey((const char *)crypt_key);
+       if (errno != 0)
+               return (0);
+       return (1);
+}
+
+bool
+DesEncrypt(clear, cipher)
+u_char *clear; /* IN  8 octets */
+u_char *cipher;        /* OUT 8 octets */
+{
+       u_char des_input[66];
+
+       Expand(clear, des_input);
+       errno = 0;
+       encrypt((char *)des_input, 0);
+       if (errno != 0)
+               return (0);
+       Collapse(des_input, cipher);
+       return (1);
+}
+
+bool
+DesDecrypt(cipher, clear)
+u_char *cipher;        /* IN  8 octets */
+u_char *clear; /* OUT 8 octets */
+{
+       u_char des_input[66];
+
+       Expand(cipher, des_input);
+       errno = 0;
+       encrypt((char *)des_input, 1);
+       if (errno != 0)
+               return (0);
+       Collapse(des_input, clear);
+       return (1);
+}
+
+#else /* USE_CRYPT */
+static des_key_schedule        key_schedule;
+
+bool
+DesSetkey(key)
+u_char *key;
+{
+       des_cblock des_key;
+       MakeKey(key, des_key);
+       des_set_key(&des_key, key_schedule);
+       return (1);
+}
+
+bool
+DesEncrypt(clear, key, cipher)
+u_char *clear; /* IN  8 octets */
+u_char *cipher;        /* OUT 8 octets */
+{
+       des_ecb_encrypt((des_cblock *)clear, (des_cblock *)cipher,
+           key_schedule, 1);
+       return (1);
+}
+
+bool
+DesDecrypt(cipher, clear)
+u_char *cipher;        /* IN  8 octets */
+u_char *clear; /* OUT 8 octets */
+{
+       des_ecb_encrypt((des_cblock *)cipher, (des_cblock *)clear,
+           key_schedule, 0);
+       return (1);
+}
+
+#endif /* USE_CRYPT */