678 lines
24 KiB
Diff
678 lines
24 KiB
Diff
From 08f5e0df46ce1ad617bcde1fd5542545397630b9 Mon Sep 17 00:00:00 2001
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From: Hans Dedecker <dedeckeh@gmail.com>
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Date: Sat, 24 Oct 2020 21:13:30 +0200
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Subject: Revert "Disallow use of DES encryption functions in new programs."
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This reverts commit b10a0accee709a5efff2fadf0b0bbb79ff0ad759.
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ppp still uses the encrypt functions from the libc while musl libc also
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provides them.
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---
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conform/data/stdlib.h-data | 3 +
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conform/data/unistd.h-data | 6 ++
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crypt/cert.c | 26 -----
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crypt/crypt-entry.c | 15 ++-
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crypt/crypt.h | 16 +++
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crypt/crypt_util.c | 9 --
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manual/conf.texi | 2 -
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manual/crypt.texi | 204 +++++++++++++++++++++++++++++++++++++
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manual/string.texi | 82 +++++++--------
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posix/unistd.h | 17 +++-
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stdlib/stdlib.h | 6 ++
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sunrpc/des_crypt.c | 7 +-
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sunrpc/des_soft.c | 2 +-
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13 files changed, 305 insertions(+), 90 deletions(-)
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--- a/conform/data/stdlib.h-data
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+++ b/conform/data/stdlib.h-data
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@@ -149,6 +149,9 @@ function {unsigned short int*} seed48 (u
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#if !defined ISO && !defined ISO99 && !defined ISO11 && !defined POSIX && !defined XPG4 && !defined XPG42 && !defined UNIX98
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function int setenv (const char*, const char*, int)
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#endif
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+#if !defined ISO && !defined ISO99 && !defined ISO11 && !defined POSIX && !defined POSIX2008
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+function void setkey (const char*)
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+#endif
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#if !defined ISO && !defined ISO99 && !defined ISO11 && !defined XPG4 && !defined POSIX && !defined POSIX2008
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function {char*} setstate (char*)
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#endif
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--- a/conform/data/unistd.h-data
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+++ b/conform/data/unistd.h-data
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@@ -437,6 +437,9 @@ function int chroot (const char*)
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function int chown (const char*, uid_t, gid_t)
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function int close (int)
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function size_t confstr (int, char*, size_t)
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+#if !defined POSIX && !defined POSIX2008
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+function {char*} crypt (const char*, const char*)
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+#endif
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#if defined XPG4 || defined XPG42 || defined UNIX98
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function {char*} ctermid (char*)
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function {char*} cuserid (char*)
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@@ -446,6 +449,9 @@ allow cuserid
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#endif
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function int dup (int)
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function int dup2 (int, int)
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+#if !defined POSIX && !defined POSIX2008
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+function void encrypt (char[64], int)
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+#endif
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function int execl (const char*, const char*, ...)
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function int execle (const char*, const char*, ...)
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function int execlp (const char*, const char*, ...)
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--- a/crypt/cert.c
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+++ b/crypt/cert.c
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@@ -10,22 +10,6 @@
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#include <stdlib.h>
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#include "crypt.h"
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-/* This file tests the deprecated setkey/encrypt interface. */
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-#include <shlib-compat.h>
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-#if TEST_COMPAT (libcrypt, GLIBC_2_0, GLIBC_2_28)
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-
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-#define libcrypt_version_reference(symbol, version) \
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- _libcrypt_version_reference (symbol, VERSION_libcrypt_##version)
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-#define _libcrypt_version_reference(symbol, version) \
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- __libcrypt_version_reference (symbol, version)
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-#define __libcrypt_version_reference(symbol, version) \
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- __asm__ (".symver " #symbol ", " #symbol "@" #version)
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-
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-extern void setkey (const char *);
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-extern void encrypt (const char *, int);
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-libcrypt_version_reference (setkey, GLIBC_2_0);
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-libcrypt_version_reference (encrypt, GLIBC_2_0);
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-
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int totfails = 0;
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int main (int argc, char *argv[]);
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@@ -119,13 +103,3 @@ put8 (char *cp)
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printf("%02x", t);
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}
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}
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-
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-#else /* encrypt and setkey are not available. */
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-
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-int
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-main (void)
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-{
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- return 77; /* UNSUPPORTED */
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-}
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-
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-#endif
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--- a/crypt/crypt-entry.c
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+++ b/crypt/crypt-entry.c
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@@ -35,7 +35,6 @@
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#endif
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#include "crypt-private.h"
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-#include <shlib-compat.h>
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/* Prototypes for local functions. */
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#ifndef __GNU_LIBRARY__
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@@ -177,7 +176,17 @@ crypt (const char *key, const char *salt
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return __crypt_r (key, salt, &_ufc_foobar);
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}
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-#if SHLIB_COMPAT (libcrypt, GLIBC_2_0, GLIBC_2_28)
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+
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+/*
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+ * To make fcrypt users happy.
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+ * They don't need to call init_des.
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+ */
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+#ifdef _LIBC
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weak_alias (crypt, fcrypt)
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-compat_symbol (libcrypt, fcrypt, fcrypt, GLIBC_2_0);
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+#else
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+char *
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+__fcrypt (const char *key, const char *salt)
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+{
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+ return crypt (key, salt);
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+}
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#endif
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--- a/crypt/crypt.h
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+++ b/crypt/crypt.h
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@@ -36,6 +36,14 @@ __BEGIN_DECLS
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extern char *crypt (const char *__phrase, const char *__salt)
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__THROW __nonnull ((1, 2));
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+/* Setup DES tables according KEY. */
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+extern void setkey (const char *__key) __THROW __nonnull ((1));
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+
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+/* Encrypt data in BLOCK in place if EDFLAG is zero; otherwise decrypt
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+ block in place. */
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+extern void encrypt (char *__glibc_block, int __edflag)
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+ __THROW __nonnull ((1));
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+
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#ifdef __USE_GNU
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/* This structure provides scratch and output buffers for 'crypt_r'.
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@@ -63,6 +71,14 @@ struct crypt_data
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extern char *crypt_r (const char *__phrase, const char *__salt,
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struct crypt_data * __restrict __data)
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__THROW __nonnull ((1, 2, 3));
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+
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+extern void setkey_r (const char *__key,
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+ struct crypt_data * __restrict __data)
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+ __THROW __nonnull ((1, 2));
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+
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+extern void encrypt_r (char *__glibc_block, int __edflag,
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+ struct crypt_data * __restrict __data)
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+ __THROW __nonnull ((1, 3));
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#endif
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__END_DECLS
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--- a/crypt/crypt_util.c
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+++ b/crypt/crypt_util.c
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@@ -34,7 +34,6 @@
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#endif
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#include "crypt-private.h"
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-#include <shlib-compat.h>
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/* Prototypes for local functions. */
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#ifndef __GNU_LIBRARY__
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@@ -151,7 +150,6 @@ static const int sbox[8][4][16]= {
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}
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};
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-#if SHLIB_COMPAT (libcrypt, GLIBC_2_0, GLIBC_2_28)
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/*
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* This is the initial
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* permutation matrix
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@@ -162,7 +160,6 @@ static const int initial_perm[64] = {
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57, 49, 41, 33, 25, 17, 9, 1, 59, 51, 43, 35, 27, 19, 11, 3,
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61, 53, 45, 37, 29, 21, 13, 5, 63, 55, 47, 39, 31, 23, 15, 7
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};
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-#endif
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/*
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* This is the final
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@@ -788,7 +785,6 @@ _ufc_output_conversion_r (ufc_long v1, u
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__data->crypt_3_buf[13] = 0;
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}
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-#if SHLIB_COMPAT (libcrypt, GLIBC_2_0, GLIBC_2_28)
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/*
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* UNIX encrypt function. Takes a bitvector
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@@ -889,14 +885,12 @@ __encrypt_r (char *__block, int __edflag
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}
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}
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weak_alias (__encrypt_r, encrypt_r)
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-compat_symbol (libcrypt, encrypt_r, encrypt_r, GLIBC_2_0);
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void
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encrypt (char *__block, int __edflag)
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{
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__encrypt_r(__block, __edflag, &_ufc_foobar);
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}
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-compat_symbol (libcrypt, encrypt, encrypt, GLIBC_2_0);
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/*
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@@ -921,15 +915,12 @@ __setkey_r (const char *__key, struct cr
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_ufc_mk_keytab_r((char *) ktab, __data);
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}
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weak_alias (__setkey_r, setkey_r)
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-compat_symbol (libcrypt, setkey_r, setkey_r, GLIBC_2_0);
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void
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setkey (const char *__key)
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{
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__setkey_r(__key, &_ufc_foobar);
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}
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-compat_symbol (libcrypt, setkey, setkey, GLIBC_2_0);
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-#endif /* SHLIB_COMPAT (libcrypt, GLIBC_2_0, GLIBC_2_28) */
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void
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__b64_from_24bit (char **cp, int *buflen,
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--- a/manual/conf.texi
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+++ b/manual/conf.texi
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@@ -780,8 +780,6 @@ Inquire about the parameter correspondin
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@item _SC_XOPEN_CRYPT
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@standards{X/Open, unistd.h}
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Inquire about the parameter corresponding to @code{_XOPEN_CRYPT}.
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-@Theglibc no longer implements the @code{_XOPEN_CRYPT} extensions,
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-so @samp{sysconf (_SC_XOPEN_CRYPT)} always returns @code{-1}.
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@item _SC_XOPEN_ENH_I18N
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@standards{X/Open, unistd.h}
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--- a/manual/crypt.texi
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+++ b/manual/crypt.texi
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@@ -16,8 +16,19 @@ subject to them, even if you do not use
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yourself. The restrictions vary from place to place and are changed
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often, so we cannot give any more specific advice than this warning.
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+@vindex AUTH_DES
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+@cindex FIPS 140-2
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+It also provides support for Secure RPC, and some library functions that
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+can be used to perform normal DES encryption. The @code{AUTH_DES}
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+authentication flavor in Secure RPC, as provided by @theglibc{},
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+uses DES and does not comply with FIPS 140-2 nor does any other use of DES
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+within @theglibc{}. It is recommended that Secure RPC should not be used
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+for systems that need to comply with FIPS 140-2 since all flavors of
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+encrypted authentication use normal DES.
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+
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@menu
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* Passphrase Storage:: One-way hashing for passphrases.
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+* crypt:: A one-way function for passwords.
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* Unpredictable Bytes:: Randomness for cryptographic purposes.
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@end menu
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@@ -190,6 +201,199 @@ unpredictable as possible; @pxref{Unpred
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@include genpass.c.texi
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@end smallexample
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+@node DES Encryption
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+@section DES Encryption
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+
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+@cindex FIPS 46-3
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+The Data Encryption Standard is described in the US Government Federal
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+Information Processing Standards (FIPS) 46-3 published by the National
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+Institute of Standards and Technology. The DES has been very thoroughly
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+analyzed since it was developed in the late 1970s, and no new
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+significant flaws have been found.
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+
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+However, the DES uses only a 56-bit key (plus 8 parity bits), and a
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+machine has been built in 1998 which can search through all possible
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+keys in about 6 days, which cost about US$200000; faster searches would
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+be possible with more money. This makes simple DES insecure for most
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+purposes, and NIST no longer permits new US government systems
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+to use simple DES.
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+
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+For serious encryption functionality, it is recommended that one of the
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+many free encryption libraries be used instead of these routines.
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+
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+The DES is a reversible operation which takes a 64-bit block and a
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+64-bit key, and produces another 64-bit block. Usually the bits are
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+numbered so that the most-significant bit, the first bit, of each block
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+is numbered 1.
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+
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+Under that numbering, every 8th bit of the key (the 8th, 16th, and so
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+on) is not used by the encryption algorithm itself. But the key must
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+have odd parity; that is, out of bits 1 through 8, and 9 through 16, and
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+so on, there must be an odd number of `1' bits, and this completely
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+specifies the unused bits.
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+
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+@deftypefun void setkey (const char *@var{key})
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+@standards{BSD, crypt.h}
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+@standards{SVID, crypt.h}
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+@safety{@prelim{}@mtunsafe{@mtasurace{:crypt}}@asunsafe{@asucorrupt{} @asulock{}}@acunsafe{@aculock{}}}
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+@c The static buffer stores the key, making it fundamentally
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+@c thread-unsafe. The locking issues are only in the initialization
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+@c path; cancelling the initialization will leave the lock held, it
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+@c would otherwise repeat the initialization on the next call.
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+
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+The @code{setkey} function sets an internal data structure to be an
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+expanded form of @var{key}. @var{key} is specified as an array of 64
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+bits each stored in a @code{char}, the first bit is @code{key[0]} and
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+the 64th bit is @code{key[63]}. The @var{key} should have the correct
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+parity.
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+@end deftypefun
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+
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+@deftypefun void encrypt (char *@var{block}, int @var{edflag})
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+@standards{BSD, crypt.h}
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+@standards{SVID, crypt.h}
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+@safety{@prelim{}@mtunsafe{@mtasurace{:crypt}}@asunsafe{@asucorrupt{} @asulock{}}@acunsafe{@aculock{}}}
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+@c Same issues as setkey.
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+
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+The @code{encrypt} function encrypts @var{block} if
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+@var{edflag} is 0, otherwise it decrypts @var{block}, using a key
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+previously set by @code{setkey}. The result is
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+placed in @var{block}.
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+
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+Like @code{setkey}, @var{block} is specified as an array of 64 bits each
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+stored in a @code{char}, but there are no parity bits in @var{block}.
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+@end deftypefun
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+
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+@deftypefun void setkey_r (const char *@var{key}, {struct crypt_data *} @var{data})
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+@deftypefunx void encrypt_r (char *@var{block}, int @var{edflag}, {struct crypt_data *} @var{data})
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+@standards{GNU, crypt.h}
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+@c setkey_r: @safety{@prelim{}@mtsafe{}@asunsafe{@asucorrupt{} @asulock{}}@acunsafe{@aculock{}}}
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+@safety{@prelim{}@mtsafe{}@asunsafe{@asucorrupt{} @asulock{}}@acunsafe{@aculock{}}}
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+
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+These are reentrant versions of @code{setkey} and @code{encrypt}. The
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+only difference is the extra parameter, which stores the expanded
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+version of @var{key}. Before calling @code{setkey_r} the first time,
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+@code{data->initialized} must be cleared to zero.
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+@end deftypefun
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+
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+The @code{setkey_r} and @code{encrypt_r} functions are GNU extensions.
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+@code{setkey}, @code{encrypt}, @code{setkey_r}, and @code{encrypt_r} are
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+defined in @file{crypt.h}.
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+
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+@deftypefun int ecb_crypt (char *@var{key}, char *@var{blocks}, unsigned int @var{len}, unsigned int @var{mode})
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+@standards{SUNRPC, rpc/des_crypt.h}
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+@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
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+
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+The function @code{ecb_crypt} encrypts or decrypts one or more blocks
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+using DES. Each block is encrypted independently.
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+
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+The @var{blocks} and the @var{key} are stored packed in 8-bit bytes, so
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+that the first bit of the key is the most-significant bit of
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+@code{key[0]} and the 63rd bit of the key is stored as the
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+least-significant bit of @code{key[7]}. The @var{key} should have the
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+correct parity.
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+
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+@var{len} is the number of bytes in @var{blocks}. It should be a
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+multiple of 8 (so that there are a whole number of blocks to encrypt).
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+@var{len} is limited to a maximum of @code{DES_MAXDATA} bytes.
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+
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+The result of the encryption replaces the input in @var{blocks}.
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+
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+The @var{mode} parameter is the bitwise OR of two of the following:
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+
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+@vtable @code
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+@item DES_ENCRYPT
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+@standards{SUNRPC, rpc/des_crypt.h}
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+This constant, used in the @var{mode} parameter, specifies that
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+@var{blocks} is to be encrypted.
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+
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+@item DES_DECRYPT
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+@standards{SUNRPC, rpc/des_crypt.h}
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+This constant, used in the @var{mode} parameter, specifies that
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+@var{blocks} is to be decrypted.
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+
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+@item DES_HW
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+@standards{SUNRPC, rpc/des_crypt.h}
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+This constant, used in the @var{mode} parameter, asks to use a hardware
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+device. If no hardware device is available, encryption happens anyway,
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+but in software.
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+
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+@item DES_SW
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+@standards{SUNRPC, rpc/des_crypt.h}
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+This constant, used in the @var{mode} parameter, specifies that no
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+hardware device is to be used.
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+@end vtable
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+
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+The result of the function will be one of these values:
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+
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+@vtable @code
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+@item DESERR_NONE
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+@standards{SUNRPC, rpc/des_crypt.h}
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+The encryption succeeded.
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+
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+@item DESERR_NOHWDEVICE
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+@standards{SUNRPC, rpc/des_crypt.h}
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+The encryption succeeded, but there was no hardware device available.
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+
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+@item DESERR_HWERROR
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+@standards{SUNRPC, rpc/des_crypt.h}
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+The encryption failed because of a hardware problem.
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+
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+@item DESERR_BADPARAM
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+@standards{SUNRPC, rpc/des_crypt.h}
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+The encryption failed because of a bad parameter, for instance @var{len}
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+is not a multiple of 8 or @var{len} is larger than @code{DES_MAXDATA}.
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+@end vtable
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+@end deftypefun
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+
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+@deftypefun int DES_FAILED (int @var{err})
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+@standards{SUNRPC, rpc/des_crypt.h}
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+@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
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+This macro returns 1 if @var{err} is a `success' result code from
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+@code{ecb_crypt} or @code{cbc_crypt}, and 0 otherwise.
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+@end deftypefun
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+
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+@deftypefun int cbc_crypt (char *@var{key}, char *@var{blocks}, unsigned int @var{len}, unsigned int @var{mode}, char *@var{ivec})
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+@standards{SUNRPC, rpc/des_crypt.h}
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+@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
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+
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+The function @code{cbc_crypt} encrypts or decrypts one or more blocks
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+using DES in Cipher Block Chaining mode.
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+
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+For encryption in CBC mode, each block is exclusive-ored with @var{ivec}
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+before being encrypted, then @var{ivec} is replaced with the result of
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+the encryption, then the next block is processed. Decryption is the
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+reverse of this process.
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+
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+This has the advantage that blocks which are the same before being
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+encrypted are very unlikely to be the same after being encrypted, making
|
|
+it much harder to detect patterns in the data.
|
|
+
|
|
+Usually, @var{ivec} is set to 8 random bytes before encryption starts.
|
|
+Then the 8 random bytes are transmitted along with the encrypted data
|
|
+(without themselves being encrypted), and passed back in as @var{ivec}
|
|
+for decryption. Another possibility is to set @var{ivec} to 8 zeroes
|
|
+initially, and have the first block encrypted consist of 8 random
|
|
+bytes.
|
|
+
|
|
+Otherwise, all the parameters are similar to those for @code{ecb_crypt}.
|
|
+@end deftypefun
|
|
+
|
|
+@deftypefun void des_setparity (char *@var{key})
|
|
+@standards{SUNRPC, rpc/des_crypt.h}
|
|
+@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
|
|
+
|
|
+The function @code{des_setparity} changes the 64-bit @var{key}, stored
|
|
+packed in 8-bit bytes, to have odd parity by altering the low bits of
|
|
+each byte.
|
|
+@end deftypefun
|
|
+
|
|
+The @code{ecb_crypt}, @code{cbc_crypt}, and @code{des_setparity}
|
|
+functions and their accompanying macros are all defined in the header
|
|
+@file{rpc/des_crypt.h}.
|
|
+
|
|
+@node Unpredictable Bytes
|
|
+@section Generating Unpredictable Bytes
|
|
+
|
|
The next program demonstrates how to verify a passphrase. It checks a
|
|
hash hardcoded into the program, because looking up real users' hashed
|
|
passphrases may require special privileges (@pxref{User Database}).
|
|
--- a/manual/string.texi
|
|
+++ b/manual/string.texi
|
|
@@ -36,8 +36,8 @@ too.
|
|
for delimiters.
|
|
* Erasing Sensitive Data:: Clearing memory which contains sensitive
|
|
data, after it's no longer needed.
|
|
-* Shuffling Bytes:: Or how to flash-cook a string.
|
|
-* Obfuscating Data:: Reversibly obscuring data from casual view.
|
|
+* strfry:: Function for flash-cooking a string.
|
|
+* Trivial Encryption:: Obscuring data.
|
|
* Encode Binary Data:: Encoding and Decoding of Binary Data.
|
|
* Argz and Envz Vectors:: Null-separated string vectors.
|
|
@end menu
|
|
@@ -2423,73 +2423,73 @@ functionality under a different name, su
|
|
systems it may be in @file{strings.h} instead.
|
|
@end deftypefun
|
|
|
|
-
|
|
-@node Shuffling Bytes
|
|
-@section Shuffling Bytes
|
|
+@node strfry
|
|
+@section strfry
|
|
|
|
The function below addresses the perennial programming quandary: ``How do
|
|
I take good data in string form and painlessly turn it into garbage?''
|
|
-This is not a difficult thing to code for oneself, but the authors of
|
|
-@theglibc{} wish to make it as convenient as possible.
|
|
+This is actually a fairly simple task for C programmers who do not use
|
|
+@theglibc{} string functions, but for programs based on @theglibc{},
|
|
+the @code{strfry} function is the preferred method for
|
|
+destroying string data.
|
|
|
|
-To @emph{erase} data, use @code{explicit_bzero} (@pxref{Erasing
|
|
-Sensitive Data}); to obfuscate it reversibly, use @code{memfrob}
|
|
-(@pxref{Obfuscating Data}).
|
|
+The prototype for this function is in @file{string.h}.
|
|
|
|
@deftypefun {char *} strfry (char *@var{string})
|
|
@standards{GNU, string.h}
|
|
@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
|
|
@c Calls initstate_r, time, getpid, strlen, and random_r.
|
|
|
|
-@code{strfry} performs an in-place shuffle on @var{string}. Each
|
|
-character is swapped to a position selected at random, within the
|
|
-portion of the string starting with the character's original position.
|
|
-(This is the Fisher-Yates algorithm for unbiased shuffling.)
|
|
-
|
|
-Calling @code{strfry} will not disturb any of the random number
|
|
-generators that have global state (@pxref{Pseudo-Random Numbers}).
|
|
+@code{strfry} creates a pseudorandom anagram of a string, replacing the
|
|
+input with the anagram in place. For each position in the string,
|
|
+@code{strfry} swaps it with a position in the string selected at random
|
|
+(from a uniform distribution). The two positions may be the same.
|
|
|
|
The return value of @code{strfry} is always @var{string}.
|
|
|
|
@strong{Portability Note:} This function is unique to @theglibc{}.
|
|
-It is declared in @file{string.h}.
|
|
+
|
|
@end deftypefun
|
|
|
|
|
|
-@node Obfuscating Data
|
|
-@section Obfuscating Data
|
|
+@node Trivial Encryption
|
|
+@section Trivial Encryption
|
|
+@cindex encryption
|
|
+
|
|
+
|
|
+The @code{memfrob} function converts an array of data to something
|
|
+unrecognizable and back again. It is not encryption in its usual sense
|
|
+since it is easy for someone to convert the encrypted data back to clear
|
|
+text. The transformation is analogous to Usenet's ``Rot13'' encryption
|
|
+method for obscuring offensive jokes from sensitive eyes and such.
|
|
+Unlike Rot13, @code{memfrob} works on arbitrary binary data, not just
|
|
+text.
|
|
@cindex Rot13
|
|
|
|
-The @code{memfrob} function reversibly obfuscates an array of binary
|
|
-data. This is not true encryption; the obfuscated data still bears a
|
|
-clear relationship to the original, and no secret key is required to
|
|
-undo the obfuscation. It is analogous to the ``Rot13'' cipher used on
|
|
-Usenet for obscuring offensive jokes, spoilers for works of fiction,
|
|
-and so on, but it can be applied to arbitrary binary data.
|
|
-
|
|
-Programs that need true encryption---a transformation that completely
|
|
-obscures the original and cannot be reversed without knowledge of a
|
|
-secret key---should use a dedicated cryptography library, such as
|
|
-@uref{https://www.gnu.org/software/libgcrypt/,,libgcrypt}.
|
|
-
|
|
-Programs that need to @emph{destroy} data should use
|
|
-@code{explicit_bzero} (@pxref{Erasing Sensitive Data}), or possibly
|
|
-@code{strfry} (@pxref{Shuffling Bytes}).
|
|
+For true encryption, @xref{Cryptographic Functions}.
|
|
+
|
|
+This function is declared in @file{string.h}.
|
|
+@pindex string.h
|
|
|
|
@deftypefun {void *} memfrob (void *@var{mem}, size_t @var{length})
|
|
@standards{GNU, string.h}
|
|
@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
|
|
|
|
-The function @code{memfrob} obfuscates @var{length} bytes of data
|
|
-beginning at @var{mem}, in place. Each byte is bitwise xor-ed with
|
|
-the binary pattern 00101010 (hexadecimal 0x2A). The return value is
|
|
-always @var{mem}.
|
|
-
|
|
-@code{memfrob} a second time on the same data returns it to
|
|
-its original state.
|
|
+@code{memfrob} transforms (frobnicates) each byte of the data structure
|
|
+at @var{mem}, which is @var{length} bytes long, by bitwise exclusive
|
|
+oring it with binary 00101010. It does the transformation in place and
|
|
+its return value is always @var{mem}.
|
|
+
|
|
+Note that @code{memfrob} a second time on the same data structure
|
|
+returns it to its original state.
|
|
+
|
|
+This is a good function for hiding information from someone who doesn't
|
|
+want to see it or doesn't want to see it very much. To really prevent
|
|
+people from retrieving the information, use stronger encryption such as
|
|
+that described in @xref{Cryptographic Functions}.
|
|
|
|
@strong{Portability Note:} This function is unique to @theglibc{}.
|
|
-It is declared in @file{string.h}.
|
|
+
|
|
@end deftypefun
|
|
|
|
@node Encode Binary Data
|
|
--- a/posix/unistd.h
|
|
+++ b/posix/unistd.h
|
|
@@ -107,6 +107,9 @@ __BEGIN_DECLS
|
|
/* The X/Open Unix extensions are available. */
|
|
#define _XOPEN_UNIX 1
|
|
|
|
+/* Encryption is present. */
|
|
+#define _XOPEN_CRYPT 1
|
|
+
|
|
/* The enhanced internationalization capabilities according to XPG4.2
|
|
are present. */
|
|
#define _XOPEN_ENH_I18N 1
|
|
@@ -1150,17 +1153,25 @@ ssize_t copy_file_range (int __infd, __o
|
|
extern int fdatasync (int __fildes);
|
|
#endif /* Use POSIX199309 */
|
|
|
|
-#ifdef __USE_MISC
|
|
+/* XPG4.2 specifies that prototypes for the encryption functions must
|
|
+ be defined here. */
|
|
+#ifdef __USE_XOPEN
|
|
/* One-way hash PHRASE, returning a string suitable for storage in the
|
|
user database. SALT selects the one-way function to use, and
|
|
ensures that no two users' hashes are the same, even if they use
|
|
the same passphrase. The return value points to static storage
|
|
which will be overwritten by the next call to crypt. */
|
|
+
|
|
+/* Encrypt at most 8 characters from KEY using salt to perturb DES. */
|
|
extern char *crypt (const char *__key, const char *__salt)
|
|
__THROW __nonnull ((1, 2));
|
|
-#endif
|
|
|
|
-#ifdef __USE_XOPEN
|
|
+/* Encrypt data in BLOCK in place if EDFLAG is zero; otherwise decrypt
|
|
+ block in place. */
|
|
+extern void encrypt (char *__glibc_block, int __edflag)
|
|
+ __THROW __nonnull ((1));
|
|
+
|
|
+
|
|
/* Swab pairs bytes in the first N bytes of the area pointed to by
|
|
FROM and copy the result to TO. The value of TO must not be in the
|
|
range [FROM - N + 1, FROM - 1]. If N is odd the first byte in FROM
|
|
--- a/stdlib/stdlib.h
|
|
+++ b/stdlib/stdlib.h
|
|
@@ -984,6 +984,12 @@ extern int getsubopt (char **__restrict
|
|
#endif
|
|
|
|
|
|
+#ifdef __USE_XOPEN
|
|
+/* Setup DES tables according KEY. */
|
|
+extern void setkey (const char *__key) __THROW __nonnull ((1));
|
|
+#endif
|
|
+
|
|
+
|
|
/* X/Open pseudo terminal handling. */
|
|
|
|
#ifdef __USE_XOPEN2KXSI
|
|
--- a/sunrpc/des_crypt.c
|
|
+++ b/sunrpc/des_crypt.c
|
|
@@ -86,9 +86,6 @@ common_crypt (char *key, char *buf, regi
|
|
return desdev == DES_SW ? DESERR_NONE : DESERR_NOHWDEVICE;
|
|
}
|
|
|
|
-/* Note: these cannot be excluded from the build yet, because they are
|
|
- still used internally. */
|
|
-
|
|
/*
|
|
* CBC mode encryption
|
|
*/
|
|
@@ -105,7 +102,7 @@ cbc_crypt (char *key, char *buf, unsigne
|
|
COPY8 (dp.des_ivec, ivec);
|
|
return err;
|
|
}
|
|
-hidden_nolink (cbc_crypt, libc, GLIBC_2_1)
|
|
+libc_hidden_nolink_sunrpc (cbc_crypt, GLIBC_2_1)
|
|
|
|
/*
|
|
* ECB mode encryption
|
|
@@ -118,4 +115,4 @@ ecb_crypt (char *key, char *buf, unsigne
|
|
dp.des_mode = ECB;
|
|
return common_crypt (key, buf, len, mode, &dp);
|
|
}
|
|
-hidden_nolink (ecb_crypt, libc, GLIBC_2_1)
|
|
+libc_hidden_nolink_sunrpc (ecb_crypt, GLIBC_2_1)
|
|
--- a/sunrpc/des_soft.c
|
|
+++ b/sunrpc/des_soft.c
|
|
@@ -71,4 +71,4 @@ des_setparity (char *p)
|
|
p++;
|
|
}
|
|
}
|
|
-hidden_nolink (des_setparity, libc, GLIBC_2_1)
|
|
+libc_hidden_nolink_sunrpc (des_setparity, GLIBC_2_1)
|