Initial revision

svn path=/trunk/; revision=14

5 files changed, 772 insertions, 0 deletions

diff --git a/getpass.c b/getpass.c
new file mode 100644
index 00000000..c5fe4829
--- /dev/null
+++ b/getpass.c
@@ -0,0 +1,223 @@
+/* Copyright 1993-95 by Carl Harris, Jr.
+ * All rights reserved
+ *
+ * Distribute freely, except: don't remove my name from the source or
+ * documentation (don't take credit for my work), mark your changes (don't
+ * get me blamed for your possible bugs), don't alter or remove this
+ * notice.  May be sold if buildable source is provided to buyer.  No
+ * warrantee of any kind, express or implied, is included with this
+ * software; use at your own risk, responsibility for damages (if any) to
+ * anyone resulting from the use of this software rests entirely with the
+ * user.
+ *
+ * Send bug reports, bug fixes, enhancements, requests, flames, etc., and
+ * I'll try to keep a version up to date.  I can be reached as follows:
+ * Carl Harris <ceharris@mal.com>
+ */
+
+
+/***********************************************************************
+  module:       getpass.c
+  project:      popclient
+  programmer:   Carl Harris, ceharris@mal.com
+  description: 	getpass() replacement which allows for long passwords.
+
+  $Log: getpass.c,v $
+  Revision 1.1  1996/06/28 14:33:54  esr
+  Initial revision
+
+  Revision 1.4  1995/08/10 00:32:27  ceharris
+  Preparation for 3.0b3 beta release:
+  -	added code for --kill/--keep, --limit, --protocol, --flush
+  	options; --pop2 and --pop3 options now obsoleted by --protocol.
+  - 	added support for APOP authentication, including --with-APOP
+  	argument for configure.
+  -	provisional and broken support for RPOP
+  -	added buffering to SockGets and SockRead functions.
+  -	fixed problem of command-line options not being correctly
+  	carried into the merged options record.
+
+  Revision 1.3  1995/08/08 01:01:19  ceharris
+  Added GNU-style long options processing.
+  Fixed password in 'ps' output problem.
+  Fixed various RCS tag blunders.
+  Integrated .poprc parser, lexer, etc into Makefile processing.
+
+ ***********************************************************************/
+
+#include <config.h>
+
+#if defined(STDC_HEADERS)
+#include <stdio.h>
+#endif
+
+#include <signal.h>
+
+#define INPUT_BUF_SIZE	MAX_PASSWORD_LENGTH
+
+#if defined(HAVE_TERMIOS_H) && defined(HAVE_TCSETATTR)
+#  include <termios.h>
+#else
+#if defined(HAVE_TERMIO_H)
+#  include <sys/ioctl.h>
+#  include <termio.h>
+#else
+#if defined(HAVE_SGTTY_H)
+#  include <sgtty.h>
+#endif
+#endif
+#endif
+
+static int ttyfd;
+
+#if defined(HAVE_TCSETATTR)
+  static struct termios termb;
+  static tcflag_t flags;
+#else
+#if defined(HAVE_TERMIO_H)
+  static struct termio termb;
+  static unsigned short flags;
+#else
+#if defined(HAVE_STTY)
+  static struct sgttyb ttyb;
+  static int flags;
+#endif
+#endif
+#endif
+
+void save_tty_state();
+void disable_tty_echo();
+void restore_tty_state();
+
+char *
+getpassword(prompt)
+char *prompt;
+{
+
+#if !(defined(HAVE_TCSETATTR) || defined(HAVE_TERMIO_H) || defined(HAVE_STTY))
+
+#if defined(HAVE_GETPASS) 
+  char *getpass();
+  return getpass(prompt);
+#else
+  fputs("ERROR: no support for getpassword() routine\n",stderr);
+  exit(1);
+#endif
+
+#endif /* !(defined(HAVE_TCSETATTR) || ... */
+
+  register char *p;
+  register c;
+  FILE *fi;
+  static char pbuf[INPUT_BUF_SIZE];
+  RETSIGTYPE (*sig)();
+  RETSIGTYPE sigint_handler();
+
+
+  /* get the file descriptor for the input device */
+  if ((fi = fdopen(open("/dev/tty", 2), "r")) == NULL)
+    fi = stdin;
+  else
+    setbuf(fi, (char *)NULL);
+
+  /* store descriptor for the tty */
+  ttyfd = fileno(fi);
+
+  /* preserve tty state before turning off echo */
+  save_tty_state();
+
+  /* now that we have the current tty state, we can catch SIGINT and  
+     exit gracefully */
+  sig = signal(SIGINT, sigint_handler);
+
+  /* turn off echo on the tty */
+  disable_tty_echo();
+
+  /* display the prompt and get the input string */
+  fprintf(stderr, "%s", prompt); fflush(stderr);
+  for (p=pbuf; (c = getc(fi))!='\n' && c!=EOF;) {
+    if (p < &pbuf[INPUT_BUF_SIZE - 1])
+      *p++ = c;
+  }
+  *p = '\0';
+
+  /* write a newline so cursor won't appear to hang */
+  fprintf(stderr, "\n"); fflush(stderr);
+
+  /* restore previous state of the tty */
+  restore_tty_state();
+
+  /* restore previous state of SIGINT */
+  signal(SIGINT, sig);
+
+  if (fi != stdin)
+    fclose(fi);
+
+  return(pbuf);
+
+}
+
+
+void
+save_tty_state ()
+{
+#if defined(HAVE_TCSETATTR)
+  tcgetattr(ttyfd, &termb);
+  flags = termb.c_lflag;
+#else
+#if defined(HAVE_TERMIO_H)
+  ioctl(ttyfd, TCGETA, (char *) &termb);
+  flags = termb.c_lflag;
+#else  /* we HAVE_STTY */
+  gtty(ttyfd, &ttyb);
+  flags = ttyb.sg_flags;
+#endif
+#endif
+}
+
+
+void
+disable_tty_echo() 
+{
+  /* turn off echo on the tty */
+#if defined(HAVE_TCSETATTR)
+  termb.c_lflag &= ~ECHO;
+  tcsetattr(ttyfd, TCSAFLUSH, &termb);
+#else
+#if defined(HAVE_TERMIO_H)
+  termb.c_lflag &= ~ECHO;
+  ioctl(ttyfd, TCSETA, (char *) &termb);
+#else  /* we HAVE_STTY */
+  ttyb.sg_flags &= ~ECHO;
+  stty(ttyfd, &ttyb);
+#endif
+#endif
+}
+
+
+
+void
+restore_tty_state()
+{
+  /* restore previous tty echo state */
+#if defined(HAVE_TCSETATTR)
+  termb.c_lflag = flags;
+  tcsetattr(ttyfd, TCSAFLUSH, &termb);
+#else
+#if defined(HAVE_TERMIO_H)
+  termb.c_lflag = flags;
+  ioctl(ttyfd, TCSETA, (char *) &termb);
+#else  /* we HAVE_STTY */
+  ttyb.sg_flags = flags;
+  stty(ttyfd, &ttyb);
+#endif
+#endif
+}
+
+
+RETSIGTYPE sigint_handler ()
+{
+  restore_tty_state();
+  fputs("\nCaught signal... bailing out.\n", stderr);
+  exit(1);
+}
diff --git a/md5.h b/md5.h
new file mode 100644
index 00000000..848894ac
--- /dev/null
+++ b/md5.h
@@ -0,0 +1,67 @@
+/*
+ * md5.h  header file for MD5 module used by popclient
+ *
+ * $Log: md5.h,v $
+ * Revision 1.1  1996/06/28 14:34:58  esr
+ * Initial revision
+ *
+ * Revision 1.2  1995/08/10 00:32:28  ceharris
+ * Preparation for 3.0b3 beta release:
+ * -	added code for --kill/--keep, --limit, --protocol, --flush
+ * 	options; --pop2 and --pop3 options now obsoleted by --protocol.
+ * - 	added support for APOP authentication, including --with-APOP
+ * 	argument for configure.
+ * -	provisional and broken support for RPOP
+ * -	added buffering to SockGets and SockRead functions.
+ * -	fixed problem of command-line options not being correctly
+ * 	carried into the merged options record.
+ *
+ * Revision 1.1  1995/08/09 14:27:22  ceharris
+ * First revision popclient MD5 support for APOP.  The MD5 code is
+ * provided by RSA Data Security.  See notice below.
+ *
+ *
+ */
+
+/* MD5.H - header file for MD5C.C
+ */
+
+/* Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
+rights reserved.
+
+License to copy and use this software is granted provided that it
+is identified as the "RSA Data Security, Inc. MD5 Message-Digest
+Algorithm" in all material mentioning or referencing this software
+or this function.
+
+License is also granted to make and use derivative works provided
+that such works are identified as "derived from the RSA Data
+Security, Inc. MD5 Message-Digest Algorithm" in all material
+mentioning or referencing the derived work.
+
+RSA Data Security, Inc. makes no representations concerning either
+the merchantability of this software or the suitability of this
+software for any particular purpose. It is provided "as is"
+without express or implied warranty of any kind.
+
+These notices must be retained in any copies of any part of this
+documentation and/or software.
+ */
+
+#ifndef MD5_H__
+#define MD5_H__
+
+#include "md5global.h"
+
+/* MD5 context. */
+typedef struct {
+  UINT4 state[4];                                   /* state (ABCD) */
+  UINT4 count[2];        /* number of bits, modulo 2^64 (lsb first) */
+  unsigned char buffer[64];                         /* input buffer */
+} MD5_CTX;
+
+void MD5Init PROTO_LIST ((MD5_CTX *));
+void MD5Update PROTO_LIST
+  ((MD5_CTX *, unsigned char *, unsigned int));
+void MD5Final PROTO_LIST ((unsigned char [16], MD5_CTX *));
+#endif /* MD5_H__ */
diff --git a/md5c.c b/md5c.c
new file mode 100644
index 00000000..9488fa71
--- /dev/null
+++ b/md5c.c
@@ -0,0 +1,359 @@
+/*
+ * md5c.c   MD5 support used by popclient.
+ *
+ * $Log: md5c.c,v $
+ * Revision 1.1  1996/06/28 14:35:47  esr
+ * Initial revision
+ *
+ * Revision 1.2  1995/08/10 00:32:30  ceharris
+ * Preparation for 3.0b3 beta release:
+ * -	added code for --kill/--keep, --limit, --protocol, --flush
+ * 	options; --pop2 and --pop3 options now obsoleted by --protocol.
+ * - 	added support for APOP authentication, including --with-APOP
+ * 	argument for configure.
+ * -	provisional and broken support for RPOP
+ * -	added buffering to SockGets and SockRead functions.
+ * -	fixed problem of command-line options not being correctly
+ * 	carried into the merged options record.
+ *
+ * Revision 1.1  1995/08/09 14:27:23  ceharris
+ * First revision popclient MD5 support for APOP.  The MD5 code is
+ * provided by RSA Data Security.  See notice below.
+ *
+ *
+ */
+
+/* MD5C.C - RSA Data Security, Inc., MD5 message-digest algorithm
+ */
+
+/* Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
+rights reserved.
+
+License to copy and use this software is granted provided that it
+is identified as the "RSA Data Security, Inc. MD5 Message-Digest
+Algorithm" in all material mentioning or referencing this software
+or this function.
+
+License is also granted to make and use derivative works provided
+that such works are identified as "derived from the RSA Data
+Security, Inc. MD5 Message-Digest Algorithm" in all material
+mentioning or referencing the derived work.
+
+RSA Data Security, Inc. makes no representations concerning either
+the merchantability of this software or the suitability of this
+software for any particular purpose. It is provided "as is"
+without express or implied warranty of any kind.
+
+These notices must be retained in any copies of any part of this
+documentation and/or software.
+ */
+
+#include <config.h>
+#include "md5global.h"
+#include "md5.h"
+
+/* Constants for MD5Transform routine.
+ */
+#define S11 7
+#define S12 12
+#define S13 17
+#define S14 22
+#define S21 5
+#define S22 9
+#define S23 14
+#define S24 20
+#define S31 4
+#define S32 11
+#define S33 16
+#define S34 23
+#define S41 6
+#define S42 10
+#define S43 15
+#define S44 21
+
+static void MD5Transform PROTO_LIST ((UINT4 [4], unsigned char [64]));
+static void Encode PROTO_LIST
+  ((unsigned char *, UINT4 *, unsigned int));
+static void Decode PROTO_LIST
+  ((UINT4 *, unsigned char *, unsigned int));
+static void MD5_memcpy PROTO_LIST ((POINTER, POINTER, unsigned int));
+static void MD5_memset PROTO_LIST ((POINTER, int, unsigned int));
+
+static unsigned char PADDING[64] = {
+  0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+};
+
+/* F, G, H and I are basic MD5 functions.
+ */
+#define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
+#define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
+#define H(x, y, z) ((x) ^ (y) ^ (z))
+#define I(x, y, z) ((y) ^ ((x) | (~z)))
+
+/* ROTATE_LEFT rotates x left n bits.
+ */
+#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
+
+/* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
+Rotation is separate from addition to prevent recomputation.
+ */
+#define FF(a, b, c, d, x, s, ac) { \
+ (a) += F ((b), (c), (d)) + (x) + (UINT4)(ac); \
+ (a) = ROTATE_LEFT ((a), (s)); \
+ (a) += (b); \
+  }
+#define GG(a, b, c, d, x, s, ac) { \
+ (a) += G ((b), (c), (d)) + (x) + (UINT4)(ac); \
+ (a) = ROTATE_LEFT ((a), (s)); \
+ (a) += (b); \
+  }
+#define HH(a, b, c, d, x, s, ac) { \
+ (a) += H ((b), (c), (d)) + (x) + (UINT4)(ac); \
+ (a) = ROTATE_LEFT ((a), (s)); \
+ (a) += (b); \
+  }
+#define II(a, b, c, d, x, s, ac) { \
+ (a) += I ((b), (c), (d)) + (x) + (UINT4)(ac); \
+ (a) = ROTATE_LEFT ((a), (s)); \
+ (a) += (b); \
+  }
+
+/* MD5 initialization. Begins an MD5 operation, writing a new context.
+ */
+void MD5Init (context)
+MD5_CTX *context;                                        /* context */
+{
+  context->count[0] = context->count[1] = 0;
+  /* Load magic initialization constants.
+*/
+  context->state[0] = 0x67452301;
+  context->state[1] = 0xefcdab89;
+  context->state[2] = 0x98badcfe;
+  context->state[3] = 0x10325476;
+}
+
+/* MD5 block update operation. Continues an MD5 message-digest
+  operation, processing another message block, and updating the
+  context.
+ */
+void MD5Update (context, input, inputLen)
+MD5_CTX *context;                                        /* context */
+unsigned char *input;                                /* input block */
+unsigned int inputLen;                     /* length of input block */
+{
+  unsigned int i, index, partLen;
+
+  /* Compute number of bytes mod 64 */
+  index = (unsigned int)((context->count[0] >> 3) & 0x3F);
+
+  /* Update number of bits */
+  if ((context->count[0] += ((UINT4)inputLen << 3))
+   < ((UINT4)inputLen << 3))
+ context->count[1]++;
+  context->count[1] += ((UINT4)inputLen >> 29);
+
+  partLen = 64 - index;
+
+  /* Transform as many times as possible.
+*/
+  if (inputLen >= partLen) {
+ MD5_memcpy
+   ((POINTER)&context->buffer[index], (POINTER)input, partLen);
+ MD5Transform (context->state, context->buffer);
+
+ for (i = partLen; i + 63 < inputLen; i += 64)
+   MD5Transform (context->state, &input[i]);
+
+ index = 0;
+  }
+  else
+ i = 0;
+
+  /* Buffer remaining input */
+  MD5_memcpy
+ ((POINTER)&context->buffer[index], (POINTER)&input[i],
+  inputLen-i);
+}
+
+/* MD5 finalization. Ends an MD5 message-digest operation, writing the
+  the message digest and zeroizing the context.
+ */
+void MD5Final (digest, context)
+unsigned char digest[16];                         /* message digest */
+MD5_CTX *context;                                       /* context */
+{
+  unsigned char bits[8];
+  unsigned int index, padLen;
+
+  /* Save number of bits */
+  Encode (bits, context->count, 8);
+
+  /* Pad out to 56 mod 64.
+*/
+  index = (unsigned int)((context->count[0] >> 3) & 0x3f);
+  padLen = (index < 56) ? (56 - index) : (120 - index);
+  MD5Update (context, PADDING, padLen);
+
+  /* Append length (before padding) */
+  MD5Update (context, bits, 8);
+  /* Store state in digest */
+  Encode (digest, context->state, 16);
+
+  /* Zeroize sensitive information.
+*/
+  MD5_memset ((POINTER)context, 0, sizeof (*context));
+}
+
+/* MD5 basic transformation. Transforms state based on block.
+ */
+static void MD5Transform (state, block)
+UINT4 state[4];
+unsigned char block[64];
+{
+  UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];
+
+  Decode (x, block, 64);
+
+  /* Round 1 */
+  FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
+  FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
+  FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
+  FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
+  FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
+  FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
+  FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
+  FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
+  FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
+  FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
+  FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
+  FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
+  FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
+  FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
+  FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
+  FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */
+
+ /* Round 2 */
+  GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
+  GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
+  GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
+  GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
+  GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
+  GG (d, a, b, c, x[10], S22,  0x2441453); /* 22 */
+  GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
+  GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
+  GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
+  GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
+  GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
+  GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
+  GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
+  GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
+  GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
+  GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */
+
+  /* Round 3 */
+  HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
+  HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
+  HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
+  HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
+  HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
+  HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
+  HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
+  HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
+  HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
+  HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
+  HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
+  HH (b, c, d, a, x[ 6], S34,  0x4881d05); /* 44 */
+  HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
+  HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
+  HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
+  HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */
+
+  /* Round 4 */
+  II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
+  II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
+  II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
+  II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
+  II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
+  II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
+  II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
+  II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
+  II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
+  II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
+  II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
+  II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
+  II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
+  II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
+  II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
+  II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */
+
+  state[0] += a;
+  state[1] += b;
+  state[2] += c;
+  state[3] += d;
+
+  /* Zeroize sensitive information.
+*/
+  MD5_memset ((POINTER)x, 0, sizeof (x));
+}
+
+/* Encodes input (UINT4) into output (unsigned char). Assumes len is
+  a multiple of 4.
+ */
+static void Encode (output, input, len)
+unsigned char *output;
+UINT4 *input;
+unsigned int len;
+{
+  unsigned int i, j;
+
+  for (i = 0, j = 0; j < len; i++, j += 4) {
+ output[j] = (unsigned char)(input[i] & 0xff);
+ output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
+ output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
+ output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
+  }
+}
+
+/* Decodes input (unsigned char) into output (UINT4). Assumes len is
+  a multiple of 4.
+ */
+static void Decode (output, input, len)
+UINT4 *output;
+unsigned char *input;
+unsigned int len;
+{
+  unsigned int i, j;
+
+  for (i = 0, j = 0; j < len; i++, j += 4)
+ output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) |
+   (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);
+}
+
+/* Note: Replace "for loop" with standard memcpy if possible.
+ */
+
+static void MD5_memcpy (output, input, len)
+POINTER output;
+POINTER input;
+unsigned int len;
+{
+  unsigned int i;
+
+  for (i = 0; i < len; i++)
+ output[i] = input[i];
+}
+
+/* Note: Replace "for loop" with standard memset if possible.
+ */
+static void MD5_memset (output, value, len)
+POINTER output;
+int value;
+unsigned int len;
+{
+  unsigned int i;
+
+  for (i = 0; i < len; i++)
+ ((char *)output)[i] = (char)value;
+}
diff --git a/md5global.h b/md5global.h
new file mode 100644
index 00000000..ba261587
--- /dev/null
+++ b/md5global.h
@@ -0,0 +1,56 @@
+/*
+ * md5global.h    Global declarations for MD5 module used by popclient
+ *
+ * $Log: md5global.h,v $
+ * Revision 1.1  1996/06/28 14:36:11  esr
+ * Initial revision
+ *
+ * Revision 1.2  1995/08/10 00:32:31  ceharris
+ * Preparation for 3.0b3 beta release:
+ * -	added code for --kill/--keep, --limit, --protocol, --flush
+ * 	options; --pop2 and --pop3 options now obsoleted by --protocol.
+ * - 	added support for APOP authentication, including --with-APOP
+ * 	argument for configure.
+ * -	provisional and broken support for RPOP
+ * -	added buffering to SockGets and SockRead functions.
+ * -	fixed problem of command-line options not being correctly
+ * 	carried into the merged options record.
+ *
+ *
+ */
+
+#ifndef MD5GLOBAL_H__
+#define MD5GLOBAL_H__ 
+/* GLOBAL.H - RSAREF types and constants
+ */
+
+/* PROTOTYPES should be set to one if and only if the compiler supports
+  function argument prototyping.
+The following makes PROTOTYPES default to 0 if it has not already
+  been defined with C compiler flags.
+ */
+
+#ifndef PROTOTYPES
+#define PROTOTYPES HAVE_PROTOTYPES
+#endif
+
+/* POINTER defines a generic pointer type */
+typedef unsigned char *POINTER;
+
+/* UINT2 defines a two byte word */
+typedef unsigned short int UINT2;
+
+/* UINT4 defines a four byte word */
+typedef unsigned long int UINT4;
+
+/* PROTO_LIST is defined depending on how PROTOTYPES is defined above.
+If using PROTOTYPES, then PROTO_LIST returns the list, otherwise it
+  returns an empty list.
+ */
+#if PROTOTYPES
+#define PROTO_LIST(list) list
+#else
+#define PROTO_LIST(list) ()
+#endif
+
+#endif  /* MD5GLOBAL_H__ */
diff --git a/md5ify.c b/md5ify.c
new file mode 100644
index 00000000..b090687f
--- /dev/null
+++ b/md5ify.c
@@ -0,0 +1,67 @@
+/* Copyright 1993-95 by Carl Harris, Jr.
+ * All rights reserved
+ *
+ * Distribute freely, except: don't remove my name from the source or
+ * documentation (don't take credit for my work), mark your changes (don't
+ * get me blamed for your possible bugs), don't alter or remove this
+ * notice.  May be sold if buildable source is provided to buyer.  No
+ * warrantee of any kind, express or implied, is included with this
+ * software; use at your own risk, responsibility for damages (if any) to
+ * anyone resulting from the use of this software rests entirely with the
+ * user.
+ *
+ * Send bug reports, bug fixes, enhancements, requests, flames, etc., and
+ * I'll try to keep a version up to date.  I can be reached as follows:
+ * Carl Harris <ceharris@mal.com>
+ */
+
+
+/***********************************************************************
+  module:       md5ify.c
+  project:      popclient
+  programmer:   Carl Harris, ceharris@mal.com
+  description:  Simple interface to MD5 module.
+
+  $Log: md5ify.c,v $
+  Revision 1.1  1996/06/28 14:36:57  esr
+  Initial revision
+
+  Revision 1.1  1995/08/10 00:32:33  ceharris
+  Preparation for 3.0b3 beta release:
+  -	added code for --kill/--keep, --limit, --protocol, --flush
+  	options; --pop2 and --pop3 options now obsoleted by --protocol.
+  - 	added support for APOP authentication, including --with-APOP
+  	argument for configure.
+  -	provisional and broken support for RPOP
+  -	added buffering to SockGets and SockRead functions.
+  -	fixed problem of command-line options not being correctly
+  	carried into the merged options record.
+
+ ***********************************************************************/
+
+#include <stdio.h>
+
+#if defined(STDC_HEADERS)
+#include <string.h>
+#endif
+
+#include "md5.h"
+
+char *
+MD5Digest (s)
+char *s;
+{
+  int i;
+  MD5_CTX context;
+  unsigned char digest[16];
+  static char ascii_digest [33];
+
+  MD5Init(&context);
+  MD5Update(&context, s, strlen(s));
+  MD5Final(digest, &context);
+  
+  for (i = 0;  i < 16;  i++) 
+    sprintf(ascii_digest+2*i, "%02x", digest[i]);
+ 
+  return(ascii_digest);
+}