#include <netinet/in.h>
  #ifdef __sun__
  #include <inttypes.h>
  #else
  #include <stdint.h>
  #endif
  #include <ctype.h>
  #include <errno.h>
  #include <string.h>
  #include <limits.h>
  #include "modpost.h"
  
  /*
   * Stolen form Cryptographic API.
   *
   * MD4 Message Digest Algorithm (RFC1320).
   *
   * Implementation derived from Andrew Tridgell and Steve French's
   * CIFS MD4 implementation, and the cryptoapi implementation
   * originally based on the public domain implementation written
   * by Colin Plumb in 1993.
   *
   * Copyright (c) Andrew Tridgell 1997-1998.
   * Modified by Steve French (sfrench@us.ibm.com) 2002
   * Copyright (c) Cryptoapi developers.
   * Copyright (c) 2002 David S. Miller (davem@redhat.com)
   * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   *
   */
  #define MD4_DIGEST_SIZE		16
  #define MD4_HMAC_BLOCK_SIZE	64
  #define MD4_BLOCK_WORDS		16
  #define MD4_HASH_WORDS		4
  
  struct md4_ctx {
  	uint32_t hash[MD4_HASH_WORDS];
  	uint32_t block[MD4_BLOCK_WORDS];
  	uint64_t byte_count;
  };
  
  static inline uint32_t lshift(uint32_t x, unsigned int s)
  {
  	x &= 0xFFFFFFFF;
  	return ((x << s) & 0xFFFFFFFF) | (x >> (32 - s));
  }
  
  static inline uint32_t F(uint32_t x, uint32_t y, uint32_t z)
  {
  	return (x & y) | ((~x) & z);
  }
  
  static inline uint32_t G(uint32_t x, uint32_t y, uint32_t z)
  {
  	return (x & y) | (x & z) | (y & z);
  }
  
  static inline uint32_t H(uint32_t x, uint32_t y, uint32_t z)
  {
  	return x ^ y ^ z;
  }
  
  #define ROUND1(a,b,c,d,k,s) (a = lshift(a + F(b,c,d) + k, s))
  #define ROUND2(a,b,c,d,k,s) (a = lshift(a + G(b,c,d) + k + (uint32_t)0x5A827999,s))
  #define ROUND3(a,b,c,d,k,s) (a = lshift(a + H(b,c,d) + k + (uint32_t)0x6ED9EBA1,s))
  
  /* XXX: this stuff can be optimized */
  static inline void le32_to_cpu_array(uint32_t *buf, unsigned int words)
  {
  	while (words--) {
  		*buf = ntohl(*buf);
  		buf++;
  	}
  }
  
  static inline void cpu_to_le32_array(uint32_t *buf, unsigned int words)
  {
  	while (words--) {
  		*buf = htonl(*buf);
  		buf++;
  	}
  }
  
  static void md4_transform(uint32_t *hash, uint32_t const *in)
  {
  	uint32_t a, b, c, d;
  
  	a = hash[0];
  	b = hash[1];
  	c = hash[2];
  	d = hash[3];
  
  	ROUND1(a, b, c, d, in[0], 3);
  	ROUND1(d, a, b, c, in[1], 7);
  	ROUND1(c, d, a, b, in[2], 11);
  	ROUND1(b, c, d, a, in[3], 19);
  	ROUND1(a, b, c, d, in[4], 3);
  	ROUND1(d, a, b, c, in[5], 7);
  	ROUND1(c, d, a, b, in[6], 11);
  	ROUND1(b, c, d, a, in[7], 19);
  	ROUND1(a, b, c, d, in[8], 3);
  	ROUND1(d, a, b, c, in[9], 7);
  	ROUND1(c, d, a, b, in[10], 11);
  	ROUND1(b, c, d, a, in[11], 19);
  	ROUND1(a, b, c, d, in[12], 3);
  	ROUND1(d, a, b, c, in[13], 7);
  	ROUND1(c, d, a, b, in[14], 11);
  	ROUND1(b, c, d, a, in[15], 19);
  
  	ROUND2(a, b, c, d,in[ 0], 3);
  	ROUND2(d, a, b, c, in[4], 5);
  	ROUND2(c, d, a, b, in[8], 9);
  	ROUND2(b, c, d, a, in[12], 13);
  	ROUND2(a, b, c, d, in[1], 3);
  	ROUND2(d, a, b, c, in[5], 5);
  	ROUND2(c, d, a, b, in[9], 9);
  	ROUND2(b, c, d, a, in[13], 13);
  	ROUND2(a, b, c, d, in[2], 3);
  	ROUND2(d, a, b, c, in[6], 5);
  	ROUND2(c, d, a, b, in[10], 9);
  	ROUND2(b, c, d, a, in[14], 13);
  	ROUND2(a, b, c, d, in[3], 3);
  	ROUND2(d, a, b, c, in[7], 5);
  	ROUND2(c, d, a, b, in[11], 9);
  	ROUND2(b, c, d, a, in[15], 13);
  
  	ROUND3(a, b, c, d,in[ 0], 3);
  	ROUND3(d, a, b, c, in[8], 9);
  	ROUND3(c, d, a, b, in[4], 11);
  	ROUND3(b, c, d, a, in[12], 15);
  	ROUND3(a, b, c, d, in[2], 3);
  	ROUND3(d, a, b, c, in[10], 9);
  	ROUND3(c, d, a, b, in[6], 11);
  	ROUND3(b, c, d, a, in[14], 15);
  	ROUND3(a, b, c, d, in[1], 3);
  	ROUND3(d, a, b, c, in[9], 9);
  	ROUND3(c, d, a, b, in[5], 11);
  	ROUND3(b, c, d, a, in[13], 15);
  	ROUND3(a, b, c, d, in[3], 3);
  	ROUND3(d, a, b, c, in[11], 9);
  	ROUND3(c, d, a, b, in[7], 11);
  	ROUND3(b, c, d, a, in[15], 15);
  
  	hash[0] += a;
  	hash[1] += b;
  	hash[2] += c;
  	hash[3] += d;
  }
  
  static inline void md4_transform_helper(struct md4_ctx *ctx)
  {
  	le32_to_cpu_array(ctx->block, sizeof(ctx->block) / sizeof(uint32_t));
  	md4_transform(ctx->hash, ctx->block);
  }
  
  static void md4_init(struct md4_ctx *mctx)
  {
  	mctx->hash[0] = 0x67452301;
  	mctx->hash[1] = 0xefcdab89;
  	mctx->hash[2] = 0x98badcfe;
  	mctx->hash[3] = 0x10325476;
  	mctx->byte_count = 0;
  }
  
  static void md4_update(struct md4_ctx *mctx,
  		       const unsigned char *data, unsigned int len)
  {
  	const uint32_t avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f);
  
  	mctx->byte_count += len;
  
  	if (avail > len) {
  		memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
  		       data, len);
  		return;
  	}
  
  	memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
  	       data, avail);
  
  	md4_transform_helper(mctx);
  	data += avail;
  	len -= avail;
  
  	while (len >= sizeof(mctx->block)) {
  		memcpy(mctx->block, data, sizeof(mctx->block));
  		md4_transform_helper(mctx);
  		data += sizeof(mctx->block);
  		len -= sizeof(mctx->block);
  	}
  
  	memcpy(mctx->block, data, len);
  }
  
  static void md4_final_ascii(struct md4_ctx *mctx, char *out, unsigned int len)
  {
  	const unsigned int offset = mctx->byte_count & 0x3f;
  	char *p = (char *)mctx->block + offset;
  	int padding = 56 - (offset + 1);
  
  	*p++ = 0x80;
  	if (padding < 0) {
  		memset(p, 0x00, padding + sizeof (uint64_t));
  		md4_transform_helper(mctx);
  		p = (char *)mctx->block;
  		padding = 56;
  	}
  
  	memset(p, 0, padding);
  	mctx->block[14] = mctx->byte_count << 3;
  	mctx->block[15] = mctx->byte_count >> 29;
  	le32_to_cpu_array(mctx->block, (sizeof(mctx->block) -
  	                  sizeof(uint64_t)) / sizeof(uint32_t));
  	md4_transform(mctx->hash, mctx->block);
  	cpu_to_le32_array(mctx->hash, sizeof(mctx->hash) / sizeof(uint32_t));
  
  	snprintf(out, len, "%08X%08X%08X%08X",
  		 mctx->hash[0], mctx->hash[1], mctx->hash[2], mctx->hash[3]);
  }
  
  static inline void add_char(unsigned char c, struct md4_ctx *md)
  {
  	md4_update(md, &c, 1);
  }
  
  static int parse_string(const char *file, unsigned long len,
  			struct md4_ctx *md)
  {
  	unsigned long i;
  
  	add_char(file[0], md);
  	for (i = 1; i < len; i++) {
  		add_char(file[i], md);
  		if (file[i] == '"' && file[i-1] != '\\')
  			break;
  	}
  	return i;
  }
  
  static int parse_comment(const char *file, unsigned long len)
  {
  	unsigned long i;
  
  	for (i = 2; i < len; i++) {
  		if (file[i-1] == '*' && file[i] == '/')
  			break;
  	}
  	return i;
  }
  
  /* FIXME: Handle .s files differently (eg. # starts comments) --RR */
  static int parse_file(const char *fname, struct md4_ctx *md)
  {
  	char *file;
  	unsigned long i, len;
  
  	file = grab_file(fname, &len);
  	if (!file)
  		return 0;
  
  	for (i = 0; i < len; i++) {
  		/* Collapse and ignore \ and CR. */
  		if (file[i] == '\\' && (i+1 < len) && file[i+1] == '
  ') {
  			i++;
  			continue;
  		}
  
  		/* Ignore whitespace */
  		if (isspace(file[i]))
  			continue;
  
  		/* Handle strings as whole units */
  		if (file[i] == '"') {
  			i += parse_string(file+i, len - i, md);
  			continue;
  		}
  
  		/* Comments: ignore */
  		if (file[i] == '/' && file[i+1] == '*') {
  			i += parse_comment(file+i, len - i);
  			continue;
  		}
  
  		add_char(file[i], md);
  	}
  	release_file(file, len);
  	return 1;
  }
  /* Check whether the file is a static library or not */
  static int is_static_library(const char *objfile)
  {
  	int len = strlen(objfile);
  	if (objfile[len - 2] == '.' && objfile[len - 1] == 'a')
  		return 1;
  	else
  		return 0;
  }
  
  /* We have dir/file.o.  Open dir/.file.o.cmd, look for source_ and deps_ line
   * to figure out source files. */
  static int parse_source_files(const char *objfile, struct md4_ctx *md)
  {
  	char *cmd, *file, *line, *dir;
  	const char *base;
  	unsigned long flen, pos = 0;
  	int dirlen, ret = 0, check_files = 0;
  
  	cmd = NOFAIL(malloc(strlen(objfile) + sizeof("..cmd")));
  
  	base = strrchr(objfile, '/');
  	if (base) {
  		base++;
  		dirlen = base - objfile;
  		sprintf(cmd, "%.*s.%s.cmd", dirlen, objfile, base);
  	} else {
  		dirlen = 0;
  		sprintf(cmd, ".%s.cmd", objfile);
  	}
  	dir = NOFAIL(malloc(dirlen + 1));
  	strncpy(dir, objfile, dirlen);
  	dir[dirlen] = '\0';
  
  	file = grab_file(cmd, &flen);
  	if (!file) {
  		warn("could not find %s for %s
  ", cmd, objfile);
  		goto out;
  	}
  
  	/* There will be a line like so:
  		deps_drivers/net/dummy.o := \
  		  drivers/net/dummy.c \
  		    $(wildcard include/config/net/fastroute.h) \
  		  include/linux/module.h \
  
  	   Sum all files in the same dir or subdirs.
  	*/
  	while ((line = get_next_line(&pos, file, flen)) != NULL) {
  		char* p = line;
  
  		if (strncmp(line, "source_", sizeof("source_")-1) == 0) {
  			p = strrchr(line, ' ');
  			if (!p) {
  				warn("malformed line: %s
  ", line);
  				goto out_file;
  			}
  			p++;
  			if (!parse_file(p, md)) {
  				warn("could not open %s: %s
  ",
  				     p, strerror(errno));
  				goto out_file;
  			}
  			continue;
  		}
  		if (strncmp(line, "deps_", sizeof("deps_")-1) == 0) {
  			check_files = 1;
  			continue;
  		}
  		if (!check_files)
  			continue;
  
  		/* Continue until line does not end with '\' */
  		if ( *(p + strlen(p)-1) != '\\')
  			break;
  		/* Terminate line at first space, to get rid of final ' \' */
  		while (*p) {
                         if (isspace(*p)) {
  				*p = '\0';
  				break;
  			}
  			p++;
  		}
  
  		/* Check if this file is in same dir as objfile */
  		if ((strstr(line, dir)+strlen(dir)-1) == strrchr(line, '/')) {
  			if (!parse_file(line, md)) {
  				warn("could not open %s: %s
  ",
  				     line, strerror(errno));
  				goto out_file;
  			}
  
  		}
  
  	}
  
  	/* Everyone parsed OK */
  	ret = 1;
  out_file:
  	release_file(file, flen);
  out:
  	free(dir);
  	free(cmd);
  	return ret;
  }
  
  /* Calc and record src checksum. */
  void get_src_version(const char *modname, char sum[], unsigned sumlen)
  {
  	void *file;
  	unsigned long len;
  	struct md4_ctx md;
  	char *sources, *end, *fname;
  	const char *basename;
  	char filelist[PATH_MAX + 1];
  	char *modverdir = getenv("MODVERDIR");
  
  	if (!modverdir)
  		modverdir = ".";
  
  	/* Source files for module are in .tmp_versions/modname.mod,
  	   after the first line. */
  	if (strrchr(modname, '/'))
  		basename = strrchr(modname, '/') + 1;
  	else
  		basename = modname;
  	snprintf(filelist, sizeof(filelist), "%s/%.*s.mod", modverdir,
  		(int) strlen(basename) - 2, basename);
  
  	file = grab_file(filelist, &len);
  	if (!file)
  		/* not a module or .mod file missing - ignore */
  		return;
  
  	sources = strchr(file, '
  ');
  	if (!sources) {
  		warn("malformed versions file for %s
  ", modname);
  		goto release;
  	}
  
  	sources++;
  	end = strchr(sources, '
  ');
  	if (!end) {
  		warn("bad ending versions file for %s
  ", modname);
  		goto release;
  	}
  	*end = '\0';
  
  	md4_init(&md);
  	while ((fname = strsep(&sources, " ")) != NULL) {
  		if (!*fname)
  			continue;
  		if (!(is_static_library(fname)) &&
  				!parse_source_files(fname, &md))
  			goto release;
  	}
  
  	md4_final_ascii(&md, sum, sumlen);
  release:
  	release_file(file, len);
  }
  
  static void write_version(const char *filename, const char *sum,
  			  unsigned long offset)
  {
  	int fd;
  
  	fd = open(filename, O_RDWR);
  	if (fd < 0) {
  		warn("changing sum in %s failed: %s
  ",
  			filename, strerror(errno));
  		return;
  	}
  
  	if (lseek(fd, offset, SEEK_SET) == (off_t)-1) {
  		warn("changing sum in %s:%lu failed: %s
  ",
  			filename, offset, strerror(errno));
  		goto out;
  	}
  
  	if (write(fd, sum, strlen(sum)+1) != strlen(sum)+1) {
  		warn("writing sum in %s failed: %s
  ",
  			filename, strerror(errno));
  		goto out;
  	}
  out:
  	close(fd);
  }
  
  static int strip_rcs_crap(char *version)
  {
  	unsigned int len, full_len;
  
  	if (strncmp(version, "$Revision", strlen("$Revision")) != 0)
  		return 0;
  
  	/* Space for version string follows. */
  	full_len = strlen(version) + strlen(version + strlen(version) + 1) + 2;
  
  	/* Move string to start with version number: prefix will be
  	 * $Revision$ or $Revision: */
  	len = strlen("$Revision");
  	if (version[len] == ':' || version[len] == '$')
  		len++;
  	while (isspace(version[len]))
  		len++;
  	memmove(version, version+len, full_len-len);
  	full_len -= len;
  
  	/* Preserve up to next whitespace. */
  	len = 0;
  	while (version[len] && !isspace(version[len]))
  		len++;
  	memmove(version + len, version + strlen(version),
  		full_len - strlen(version));
  	return 1;
  }
  
  /* Clean up RCS-style version numbers. */
  void maybe_frob_rcs_version(const char *modfilename,
  			    char *version,
  			    void *modinfo,
  			    unsigned long version_offset)
  {
  	if (strip_rcs_crap(version))
  		write_version(modfilename, version, version_offset);
  }