Prepare for radical source tree reorganization. zack/build-layout-experiment

All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).

1 files changed, 429 insertions, 0 deletions

diff --git a/REORG.TODO/crypt/sha256-crypt.c b/REORG.TODO/crypt/sha256-crypt.c
new file mode 100644
index 0000000000..561ff577bf
--- /dev/null
+++ b/REORG.TODO/crypt/sha256-crypt.c
@@ -0,0 +1,429 @@
+/* One way encryption based on SHA256 sum.
+   Copyright (C) 2007-2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@redhat.com>, 2007.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <assert.h>
+#include <errno.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h>
+#include <sys/param.h>
+
+#include "sha256.h"
+#include "crypt-private.h"
+
+
+#ifdef USE_NSS
+typedef int PRBool;
+# include <hasht.h>
+# include <nsslowhash.h>
+
+# define sha256_init_ctx(ctxp, nss_ctxp) \
+  do									      \
+    {									      \
+      if (((nss_ctxp = NSSLOWHASH_NewContext (nss_ictx, HASH_AlgSHA256))      \
+	   == NULL))							      \
+	{								      \
+	  if (nss_ctx != NULL)						      \
+	    NSSLOWHASH_Destroy (nss_ctx);				      \
+	  if (nss_alt_ctx != NULL)					      \
+	    NSSLOWHASH_Destroy (nss_alt_ctx);				      \
+	  return NULL;							      \
+	}								      \
+      NSSLOWHASH_Begin (nss_ctxp);					      \
+    }									      \
+  while (0)
+
+# define sha256_process_bytes(buf, len, ctxp, nss_ctxp) \
+  NSSLOWHASH_Update (nss_ctxp, (const unsigned char *) buf, len)
+
+# define sha256_finish_ctx(ctxp, nss_ctxp, result) \
+  do									      \
+    {									      \
+      unsigned int ret;							      \
+      NSSLOWHASH_End (nss_ctxp, result, &ret, sizeof (result));		      \
+      assert (ret == sizeof (result));					      \
+      NSSLOWHASH_Destroy (nss_ctxp);					      \
+      nss_ctxp = NULL;							      \
+    }									      \
+  while (0)
+#else
+# define sha256_init_ctx(ctxp, nss_ctxp) \
+  __sha256_init_ctx (ctxp)
+
+# define sha256_process_bytes(buf, len, ctxp, nss_ctxp) \
+  __sha256_process_bytes(buf, len, ctxp)
+
+# define sha256_finish_ctx(ctxp, nss_ctxp, result) \
+  __sha256_finish_ctx (ctxp, result)
+#endif
+
+
+/* Define our magic string to mark salt for SHA256 "encryption"
+   replacement.  */
+static const char sha256_salt_prefix[] = "$5$";
+
+/* Prefix for optional rounds specification.  */
+static const char sha256_rounds_prefix[] = "rounds=";
+
+/* Maximum salt string length.  */
+#define SALT_LEN_MAX 16
+/* Default number of rounds if not explicitly specified.  */
+#define ROUNDS_DEFAULT 5000
+/* Minimum number of rounds.  */
+#define ROUNDS_MIN 1000
+/* Maximum number of rounds.  */
+#define ROUNDS_MAX 999999999
+
+
+/* Prototypes for local functions.  */
+extern char *__sha256_crypt_r (const char *key, const char *salt,
+			       char *buffer, int buflen);
+extern char *__sha256_crypt (const char *key, const char *salt);
+
+
+char *
+__sha256_crypt_r (const char *key, const char *salt, char *buffer, int buflen)
+{
+  unsigned char alt_result[32]
+    __attribute__ ((__aligned__ (__alignof__ (uint32_t))));
+  unsigned char temp_result[32]
+    __attribute__ ((__aligned__ (__alignof__ (uint32_t))));
+  size_t salt_len;
+  size_t key_len;
+  size_t cnt;
+  char *cp;
+  char *copied_key = NULL;
+  char *copied_salt = NULL;
+  char *p_bytes;
+  char *s_bytes;
+  /* Default number of rounds.  */
+  size_t rounds = ROUNDS_DEFAULT;
+  bool rounds_custom = false;
+  size_t alloca_used = 0;
+  char *free_key = NULL;
+  char *free_pbytes = NULL;
+
+  /* Find beginning of salt string.  The prefix should normally always
+     be present.  Just in case it is not.  */
+  if (strncmp (sha256_salt_prefix, salt, sizeof (sha256_salt_prefix) - 1) == 0)
+    /* Skip salt prefix.  */
+    salt += sizeof (sha256_salt_prefix) - 1;
+
+  if (strncmp (salt, sha256_rounds_prefix, sizeof (sha256_rounds_prefix) - 1)
+      == 0)
+    {
+      const char *num = salt + sizeof (sha256_rounds_prefix) - 1;
+      char *endp;
+      unsigned long int srounds = strtoul (num, &endp, 10);
+      if (*endp == '$')
+	{
+	  salt = endp + 1;
+	  rounds = MAX (ROUNDS_MIN, MIN (srounds, ROUNDS_MAX));
+	  rounds_custom = true;
+	}
+    }
+
+  salt_len = MIN (strcspn (salt, "$"), SALT_LEN_MAX);
+  key_len = strlen (key);
+
+  if ((key - (char *) 0) % __alignof__ (uint32_t) != 0)
+    {
+      char *tmp;
+
+      if (__libc_use_alloca (alloca_used + key_len + __alignof__ (uint32_t)))
+	tmp = alloca_account (key_len + __alignof__ (uint32_t), alloca_used);
+      else
+	{
+	  free_key = tmp = (char *) malloc (key_len + __alignof__ (uint32_t));
+	  if (tmp == NULL)
+	    return NULL;
+	}
+
+      key = copied_key =
+	memcpy (tmp + __alignof__ (uint32_t)
+		- (tmp - (char *) 0) % __alignof__ (uint32_t),
+		key, key_len);
+      assert ((key - (char *) 0) % __alignof__ (uint32_t) == 0);
+    }
+
+  if ((salt - (char *) 0) % __alignof__ (uint32_t) != 0)
+    {
+      char *tmp = (char *) alloca (salt_len + __alignof__ (uint32_t));
+      alloca_used += salt_len + __alignof__ (uint32_t);
+      salt = copied_salt =
+	memcpy (tmp + __alignof__ (uint32_t)
+		- (tmp - (char *) 0) % __alignof__ (uint32_t),
+		salt, salt_len);
+      assert ((salt - (char *) 0) % __alignof__ (uint32_t) == 0);
+    }
+
+#ifdef USE_NSS
+  /* Initialize libfreebl3.  */
+  NSSLOWInitContext *nss_ictx = NSSLOW_Init ();
+  if (nss_ictx == NULL)
+    {
+      free (free_key);
+      return NULL;
+    }
+  NSSLOWHASHContext *nss_ctx = NULL;
+  NSSLOWHASHContext *nss_alt_ctx = NULL;
+#else
+  struct sha256_ctx ctx;
+  struct sha256_ctx alt_ctx;
+#endif
+
+  /* Prepare for the real work.  */
+  sha256_init_ctx (&ctx, nss_ctx);
+
+  /* Add the key string.  */
+  sha256_process_bytes (key, key_len, &ctx, nss_ctx);
+
+  /* The last part is the salt string.  This must be at most 16
+     characters and it ends at the first `$' character.  */
+  sha256_process_bytes (salt, salt_len, &ctx, nss_ctx);
+
+
+  /* Compute alternate SHA256 sum with input KEY, SALT, and KEY.  The
+     final result will be added to the first context.  */
+  sha256_init_ctx (&alt_ctx, nss_alt_ctx);
+
+  /* Add key.  */
+  sha256_process_bytes (key, key_len, &alt_ctx, nss_alt_ctx);
+
+  /* Add salt.  */
+  sha256_process_bytes (salt, salt_len, &alt_ctx, nss_alt_ctx);
+
+  /* Add key again.  */
+  sha256_process_bytes (key, key_len, &alt_ctx, nss_alt_ctx);
+
+  /* Now get result of this (32 bytes) and add it to the other
+     context.  */
+  sha256_finish_ctx (&alt_ctx, nss_alt_ctx, alt_result);
+
+  /* Add for any character in the key one byte of the alternate sum.  */
+  for (cnt = key_len; cnt > 32; cnt -= 32)
+    sha256_process_bytes (alt_result, 32, &ctx, nss_ctx);
+  sha256_process_bytes (alt_result, cnt, &ctx, nss_ctx);
+
+  /* Take the binary representation of the length of the key and for every
+     1 add the alternate sum, for every 0 the key.  */
+  for (cnt = key_len; cnt > 0; cnt >>= 1)
+    if ((cnt & 1) != 0)
+      sha256_process_bytes (alt_result, 32, &ctx, nss_ctx);
+    else
+      sha256_process_bytes (key, key_len, &ctx, nss_ctx);
+
+  /* Create intermediate result.  */
+  sha256_finish_ctx (&ctx, nss_ctx, alt_result);
+
+  /* Start computation of P byte sequence.  */
+  sha256_init_ctx (&alt_ctx, nss_alt_ctx);
+
+  /* For every character in the password add the entire password.  */
+  for (cnt = 0; cnt < key_len; ++cnt)
+    sha256_process_bytes (key, key_len, &alt_ctx, nss_alt_ctx);
+
+  /* Finish the digest.  */
+  sha256_finish_ctx (&alt_ctx, nss_alt_ctx, temp_result);
+
+  /* Create byte sequence P.  */
+  if (__libc_use_alloca (alloca_used + key_len))
+    cp = p_bytes = (char *) alloca (key_len);
+  else
+    {
+      free_pbytes = cp = p_bytes = (char *)malloc (key_len);
+      if (free_pbytes == NULL)
+	{
+	  free (free_key);
+	  return NULL;
+	}
+    }
+
+  for (cnt = key_len; cnt >= 32; cnt -= 32)
+    cp = mempcpy (cp, temp_result, 32);
+  memcpy (cp, temp_result, cnt);
+
+  /* Start computation of S byte sequence.  */
+  sha256_init_ctx (&alt_ctx, nss_alt_ctx);
+
+  /* For every character in the password add the entire password.  */
+  for (cnt = 0; cnt < 16 + alt_result[0]; ++cnt)
+    sha256_process_bytes (salt, salt_len, &alt_ctx, nss_alt_ctx);
+
+  /* Finish the digest.  */
+  sha256_finish_ctx (&alt_ctx, nss_alt_ctx, temp_result);
+
+  /* Create byte sequence S.  */
+  cp = s_bytes = alloca (salt_len);
+  for (cnt = salt_len; cnt >= 32; cnt -= 32)
+    cp = mempcpy (cp, temp_result, 32);
+  memcpy (cp, temp_result, cnt);
+
+  /* Repeatedly run the collected hash value through SHA256 to burn
+     CPU cycles.  */
+  for (cnt = 0; cnt < rounds; ++cnt)
+    {
+      /* New context.  */
+      sha256_init_ctx (&ctx, nss_ctx);
+
+      /* Add key or last result.  */
+      if ((cnt & 1) != 0)
+	sha256_process_bytes (p_bytes, key_len, &ctx, nss_ctx);
+      else
+	sha256_process_bytes (alt_result, 32, &ctx, nss_ctx);
+
+      /* Add salt for numbers not divisible by 3.  */
+      if (cnt % 3 != 0)
+	sha256_process_bytes (s_bytes, salt_len, &ctx, nss_ctx);
+
+      /* Add key for numbers not divisible by 7.  */
+      if (cnt % 7 != 0)
+	sha256_process_bytes (p_bytes, key_len, &ctx, nss_ctx);
+
+      /* Add key or last result.  */
+      if ((cnt & 1) != 0)
+	sha256_process_bytes (alt_result, 32, &ctx, nss_ctx);
+      else
+	sha256_process_bytes (p_bytes, key_len, &ctx, nss_ctx);
+
+      /* Create intermediate result.  */
+      sha256_finish_ctx (&ctx, nss_ctx, alt_result);
+    }
+
+#ifdef USE_NSS
+  /* Free libfreebl3 resources. */
+  NSSLOW_Shutdown (nss_ictx);
+#endif
+
+  /* Now we can construct the result string.  It consists of three
+     parts.  */
+  cp = __stpncpy (buffer, sha256_salt_prefix, MAX (0, buflen));
+  buflen -= sizeof (sha256_salt_prefix) - 1;
+
+  if (rounds_custom)
+    {
+      int n = __snprintf (cp, MAX (0, buflen), "%s%zu$",
+			  sha256_rounds_prefix, rounds);
+      cp += n;
+      buflen -= n;
+    }
+
+  cp = __stpncpy (cp, salt, MIN ((size_t) MAX (0, buflen), salt_len));
+  buflen -= MIN ((size_t) MAX (0, buflen), salt_len);
+
+  if (buflen > 0)
+    {
+      *cp++ = '$';
+      --buflen;
+    }
+
+  __b64_from_24bit (&cp, &buflen,
+		    alt_result[0], alt_result[10], alt_result[20], 4);
+  __b64_from_24bit (&cp, &buflen,
+		    alt_result[21], alt_result[1], alt_result[11], 4);
+  __b64_from_24bit (&cp, &buflen,
+		    alt_result[12], alt_result[22], alt_result[2], 4);
+  __b64_from_24bit (&cp, &buflen,
+		    alt_result[3], alt_result[13], alt_result[23], 4);
+  __b64_from_24bit (&cp, &buflen,
+		    alt_result[24], alt_result[4], alt_result[14], 4);
+  __b64_from_24bit (&cp, &buflen,
+		    alt_result[15], alt_result[25], alt_result[5], 4);
+  __b64_from_24bit (&cp, &buflen,
+		    alt_result[6], alt_result[16], alt_result[26], 4);
+  __b64_from_24bit (&cp, &buflen,
+		    alt_result[27], alt_result[7], alt_result[17], 4);
+  __b64_from_24bit (&cp, &buflen,
+		    alt_result[18], alt_result[28], alt_result[8], 4);
+  __b64_from_24bit (&cp, &buflen,
+		    alt_result[9], alt_result[19], alt_result[29], 4);
+  __b64_from_24bit (&cp, &buflen,
+		    0, alt_result[31], alt_result[30], 3);
+  if (buflen <= 0)
+    {
+      __set_errno (ERANGE);
+      buffer = NULL;
+    }
+  else
+    *cp = '\0';		/* Terminate the string.  */
+
+  /* Clear the buffer for the intermediate result so that people
+     attaching to processes or reading core dumps cannot get any
+     information.  We do it in this way to clear correct_words[]
+     inside the SHA256 implementation as well.  */
+#ifndef USE_NSS
+  __sha256_init_ctx (&ctx);
+  __sha256_finish_ctx (&ctx, alt_result);
+  explicit_bzero (&ctx, sizeof (ctx));
+  explicit_bzero (&alt_ctx, sizeof (alt_ctx));
+#endif
+  explicit_bzero (temp_result, sizeof (temp_result));
+  explicit_bzero (p_bytes, key_len);
+  explicit_bzero (s_bytes, salt_len);
+  if (copied_key != NULL)
+    explicit_bzero (copied_key, key_len);
+  if (copied_salt != NULL)
+    explicit_bzero (copied_salt, salt_len);
+
+  free (free_key);
+  free (free_pbytes);
+  return buffer;
+}
+
+#ifndef _LIBC
+# define libc_freeres_ptr(decl) decl
+#endif
+libc_freeres_ptr (static char *buffer);
+
+/* This entry point is equivalent to the `crypt' function in Unix
+   libcs.  */
+char *
+__sha256_crypt (const char *key, const char *salt)
+{
+  /* We don't want to have an arbitrary limit in the size of the
+     password.  We can compute an upper bound for the size of the
+     result in advance and so we can prepare the buffer we pass to
+     `sha256_crypt_r'.  */
+  static int buflen;
+  int needed = (sizeof (sha256_salt_prefix) - 1
+		+ sizeof (sha256_rounds_prefix) + 9 + 1
+		+ strlen (salt) + 1 + 43 + 1);
+
+  if (buflen < needed)
+    {
+      char *new_buffer = (char *) realloc (buffer, needed);
+      if (new_buffer == NULL)
+	return NULL;
+
+      buffer = new_buffer;
+      buflen = needed;
+    }
+
+  return __sha256_crypt_r (key, salt, buffer, buflen);
+}
+
+#ifndef _LIBC
+static void
+__attribute__ ((__destructor__))
+free_mem (void)
+{
+  free (buffer);
+}
+#endif