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2020-04-09Add GRND_INSECURE from Linux 5.6 to sys/random.hJoseph Myers1-0/+3
This patch adds the GRND_INSECURE constant from Linux 5.6 to glibc's sys/random.h. This is also added to the documentation. The constant acts as a no-op for the Hurd implementation (as that doesn't check whether the flags are known), which is semantically fine, while older Linux kernels reject unknown flags with an EINVAL error. Tested for x86_64.
2018-06-29manual: Revise crypt.texi.Zack Weinberg1-141/+251
This is a major rewrite of the description of 'crypt', 'getentropy', and 'getrandom'. A few highlights of the content changes: - Throughout the manual, public headers, and user-visible messages, I replaced the term "password" with "passphrase", the term "password database" with "user database", and the term "encrypt(ion)" with "(one-way) hashing" whenever it was applied to passphrases. I didn't bother making this change in internal code or tests. The use of the term "password" in ruserpass.c survives, because that refers to a keyword in netrc files, but it is adjusted to make this clearer. There is a note in crypt.texi explaining that they were traditionally called passwords but single words are not good enough anymore, and a note in users.texi explaining that actual passphrase hashes are found in a "shadow" database nowadays. - There is a new short introduction to the "Cryptographic Functions" section, explaining how we do not intend to be a general-purpose cryptography library, and cautioning that there _are_, or have been, legal restrictions on the use of cryptography in many countries, without getting into any kind of detail that we can't promise to keep up to date. - I added more detail about what a "one-way function" is, and why they are used to obscure passphrases for storage. I removed the paragraph saying that systems not connected to a network need no user authentication, because that's a pretty rare situation nowadays. (It still says "sometimes it is necessary" to authenticate the user, though.) - I added documentation for all of the hash functions that glibc actually supports, but not for the additional hash functions supported by libxcrypt. If we're going to keep this manual section around after the transition is more advanced, it would probably make sense to add them then. - There is much more detailed discussion of how to generate a salt, and the failure behavior for crypt is documented. (Returning an invalid hash on failure is what libxcrypt does; Solar Designer's notes say that this was done "for compatibility with old programs that assume crypt can never fail".) - As far as I can tell, the header 'crypt.h' is entirely a GNU invention, and never existed on any other Unix lineage. The function 'crypt', however, was in Issue 1 of the SVID and is now in the XSI component of POSIX. I tried to make all of the @standards annotations consistent with this, but I'm not sure I got them perfectly right. - The genpass.c example has been improved to use getentropy instead of the current time to generate the salt, and to use a SHA-256 hash instead of MD5. It uses more random bytes than is strictly necessary because I didn't want to complicate the code with proper base64 encoding. - The testpass.c example has three hardwired hashes now, to demonstrate that different one-way functions produce different hashes for the same input. It also demonstrates how DES hashing only pays attention to the first eight characters of the input. - There is new text explaining in more detail how a CSPRNG differs from a regular random number generator, and how getentropy/getrandom are not exactly a CSPRNG. I tried not to make specific falsifiable claims here. I also tried to make the blocking/cancellation/error behavior of both getentropy and getrandom clearer.
2018-06-29manual: Reorganize crypt.texi.Zack Weinberg1-119/+28
In preparation for a major revision of the documentation for crypt(_r), getentropy, and getrandom, reorganize crypt.texi. This patch does not change any text; it only deletes and moves text. The description of 'getpass' moves to terminal.texi, since all it does is read a password from the controlling terminal with echo disabled. The "Legal Problems" section of crypt.texi is dropped, and the introductory text is shifted down to the "Encrypting Passwords" section; the next patch will add some new introductory text. Also, it is no longer true that crypt.texi's top @node needs to have no pointers. That was a vestige of crypt/ being an add-on. (makeinfo itself doesn't need @node pointers anymore, but the scripts that assemble the libc manual's topmost node rely on each chapter-level node having them.)
2018-06-29Disallow use of DES encryption functions in new programs.Zack Weinberg1-201/+0
The functions encrypt, setkey, encrypt_r, setkey_r, cbc_crypt, ecb_crypt, and des_setparity should not be used in new programs, because they use the DES block cipher, which is unacceptably weak by modern standards. Demote all of them to compatibility symbols, and remove their prototypes from installed headers. cbc_crypt, ecb_crypt, and des_setparity were already compat symbols when glibc was configured with --disable-obsolete-rpc. POSIX requires encrypt and setkey to be available when _XOPEN_CRYPT is defined, so this change also removes the definition of X_OPEN_CRYPT from <unistd.h>. The entire "DES Encryption" section is dropped from the manual, as is the mention of AUTH_DES and FIPS 140-2 in the introduction to crypt.texi. The documentation of 'memfrob' cross-referenced the DES Encryption section, which is replaced by a hyperlink to libgcrypt, and while I was in there I spruced up the actual documentation of 'memfrob' and 'strfry' a little. It's still fairly jokey, because those functions _are_ jokes, but they do also have real use cases, so people trying to use them for real should have all the information they need. DES-based authentication for Sun RPC is also insecure and should be deprecated or even removed, but maybe that can be left as TI-RPC's problem.
2017-06-15manual: Replace summary.awk with summary.pl.Rical Jasan1-42/+23
The Summary is now generated from @standards, and syntax-checking is performed. If invalid @standards syntax is detected, summary.pl will fail, reporting all errors. Failure and error reporting is disabled for now, however, since much of the manual is still incomplete wrt. header and standards annotations. Note that the sorting order of the Summary has changed; summary.pl respects the locale, like summary.awk did, but the use of LC_ALL=C is introduced in the Makefile. Other notable deviations are improved detection of the annotated elements' names, which are used for sorting, and improved detection of the @node used to reference into the manual. The most noticeable difference in the rendered Summary is that entries may now contain multiple lines, one for each header and standard combination. summary.pl accepts a `--help' option, which details the expected syntax of @standards. If errors are reported, the user is directed to this feature for further information. * manual/Makefile: Generate summary.texi with summary.pl. Force use of the C locale. Update Perl dependency comment. * manual/header.texi: Update reference to summary.awk. * manual/macros.texi: Refer authors to `summary.pl --help'. * manual/summary.awk: Remove file. * manual/summary.pl: New file. Generate summary.texi, and check for @standards-related syntax errors. * manual/argp.texi: Convert header and standards @comments to @standards. * manual/arith.texi: Likewise. * manual/charset.texi: Likewise. * manual/conf.texi: Likewise. * manual/creature.texi: Likewise. * manual/crypt.texi: Likewise. * manual/ctype.texi: Likewise. * manual/debug.texi: Likewise. * manual/errno.texi: Likewise. * manual/filesys.texi: Likewise. * manual/getopt.texi: Likewise. * manual/job.texi: Likewise. * manual/lang.texi: Likewise. * manual/llio.texi: Likewise. * manual/locale.texi: Likewise. * manual/math.texi: Likewise. * manual/memory.texi: Likewise. * manual/message.texi: Likewise. * manual/pattern.texi: Likewise. * manual/pipe.texi: Likewise. * manual/process.texi: Likewise. * manual/resource.texi: Likewise. * manual/search.texi: Likewise. * manual/setjmp.texi: Likewise. * manual/signal.texi: Likewise. * manual/socket.texi: Likewise. * manual/startup.texi: Likewise. * manual/stdio.texi: Likewise. * manual/string.texi: Likewise. * manual/sysinfo.texi: Likewise. * manual/syslog.texi: Likewise. * manual/terminal.texi: Likewise. * manual/threads.texi: Likewise. * manual/time.texi: Likewise. * manual/users.texi: Likewise.
2017-05-18manual: Fix up invalid header and standards syntax.Rical Jasan1-1/+1
This commit handles exceptional cases of invalid syntax for the @standards conversion script. * manual/crypt.texi: Move a comment out of an @*x list. * manual/filesys.texi: Refactor some comments, one of which looks like a standard. Fix incorrectly separated standards. * manual/locale.texi: Invert an annotation. * manual/resource.texi: Fix incorrectly separated standards. * manual/time.texi: Refactor a @vtable that obscures an annotation. * manual/users.texi: Refactor multiple headers to occupy a single @comment.
2016-12-12Add getentropy, getrandom, <sys/random.h> [BZ #17252]Florian Weimer1-0/+112
2016-10-06Manual typos: DES Encryption and Password HandlingRical Jasan1-4/+4
2016-05-06 Rical Jasan <ricaljasan@pacific.net> * manual/crypt.texi: Fix typos in the manual.
2016-06-16manual: fix spelling typosMike Frysinger1-1/+1
I've bracketed the changes to make it easier to pick out. enlengthen -> extend enlengthened -> extended excep[e]tions -> exceptions exten[da]ble -> exten[si]ble implement[o]r -> implement[e]r licen[c]e -> licen[s]e optimzed -> optim[i]zed overriden -> overrid[d]en param[a]ter -> param[e]ter Signed-off-by: Mike Frysinger <vapier@gentoo.org> 2012-10-27 Mike Frysinger <vapier@gentoo.org> * manual/arith.texi: Fix spelling typos. * manual/contrib.texi: Likewise. * manual/crypt.texi: Likewise. * manual/filesys.texi: Likewise. * manual/llio.texi: Likewise. * manual/locale.texi: Likewise. * manual/message.texi: Likewise. * manual/nss.texi: Likewise. * manual/socket.texi: Likewise. * manual/stdio.texi: Likewise. * manual/string.texi: Likewise. * manual/sysinfo.texi: Likewise.
2014-01-29* manual/crypt.texi: Document MTASC-safety properties.Alexandre Oliva1-0/+30
2013-10-19Mention FIPS 140-2 compliance and Sun RPC.Carlos O'Donell1-1/+9
The Secure RPC implementation in glibc uses DES encryption during authentication of the user. This use of DES means that anyone using Sun RPC will likely not be compliant with FIPS 140-2 which forbids the use of DES. One solution to the compliance issue is to disable AUTH_DES and AUTH_KERB, both use DES, when in FIPS compliance mode. This is not a good idea because it disables all of the even mildly secure methods of authentication allowing only plain text methods. Instead we leave AUTH_DES and AUTH_KERB enabled in FIPS compliance mode and document the compliance issue in the manual. FIPS allows this, that is to say that if you can't fix it you must document the non-compliance. This commit adds documentation to that effect in the "DES encryption and password handling" section of the manual.
2012-02-28Use Texinfo macros to refer to the GNU C Library within the manual.Joseph Myers1-2/+2
2004-05-17[BZ #40]Ulrich Drepper1-2/+2
Update. 2004-05-15 Petter Reinholdtsen <pere@hungry.com> * locale/iso-3166.def: Remove YUGOSLAVIA and insert "SERBIA AND MONTENEGRO" which have taken over the code 819. Patch from Danilo Segan. [BZ #40] 2004-05-15 Jakub Jelinek <jakub@redhat.com> * sysdeps/unix/sysv/linux/sparc/sparc32/sysdep.h (SYSCALL_ERROR_HANDLER): Rename __sparc.get_pic.l7 to __sparc_get_pic_l7. 2004-05-15 Joseph S. Myers <jsm@polyomino.org.uk> * catgets/gencat.c: Update bug reporting instructions. * csu/version.c: Likewise. * debug/catchsegv.sh: Likewise. * debug/pcprofiledump.c: Likewise. * debug/xtrace.sh: Likewise. * elf/ldd.bash.in: Likewise. * iconv/iconv_prog.c: Likewise. * iconv/iconvconfig.c: Likewise. * locale/programs/locale.c: Likewise. * locale/programs/localedef.c: Likewise. * login/programs/pt_chown.c: Likewise. * malloc/memusage.sh: Likewise. * malloc/memusagestat.c: Likewise. * malloc/mtrace.pl: Likewise. * manual/crypt.texi: Likewise. * manual/install.texi: Likewise. * nss/makedb.c: Likewise. 2004-05-14 Jakub Jelinek <jakub@redhat.com> * sysdeps/sparc/sparc32/dl-machine.h (elf_machine_rela): Only CHECK_STATIC_TLS if sym != NULL. * sysdeps/sh/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/i386/dl-machine.h (elf_machine_rela): Likewise. 2004-05-12 Andreas Schwab <schwab@suse.de> * posix/regex_internal.c (build_wcs_buffer): Also set pstr->mbs when translating. 2004-05-13 H.J. Lu <hongjiu.lu@intel.com> * Rules (xtests): Depend on tests.
2002-11-132002-11-11 Paul Eggert <eggert@twinsun.com>Roland McGrath1-4/+7
* manual/crypt.texi (Cryptographic Functions): Mention that the MD5 one-way algorithm is compatible with BSD's.
2001-05-21Update.Andreas Jaeger1-5/+5
2001-05-21 Andreas Jaeger <aj@suse.de> * locale/programs/ld-collate.c (handle_ellipsis): Fix message. Patch by Philipp Thomas <pthomas@suse.de>.
2001-02-13Update.Ulrich Drepper1-15/+5
* iconvdata/Makefile (modules): Add GBBIG5. (distribute): Add gbbig5.c. * iconvdata/gbbig5.c: New file. * iconvdata/gconv-modules: Add entries for GBBIG5 module. 2001-02-13 Philip Blundell <pb@futuretv.com> * manual/crypt.texi: Remove outdated references to crypt add-on. * manual/creature.texi: Improve wording slightly. 2001-02-13 Ulrich Drepper <drepper@redhat.com>
2001-02-11(Currency Symbol): Add INT_ constants and CODESET:Ulrich Drepper1-33/+19
2001-01-17Update.Ulrich Drepper1-5/+5
2001-01-17 Ulrich Drepper <drepper@redhat.com> * manual/Makefile (chapters): Add debug. * manual/debug.texi: New file. * manual/examples/execinfo.c: New file. Patch by suckfish@ihug.co.nz.
2000-03-08Update.Andreas Jaeger1-3/+3
2000-03-08 Andreas Jaeger <aj@suse.de> * manual/crypt.texi: Fix paths.
2000-02-29Update.Ulrich Drepper1-1/+2
* crypt/crypt.texi: Moved to... * crypt/examples/genpass.c: Moved to... * manual/examples/genpass.c: ...here. * crypt/examples/mygenpass.c: Moved to... * manual/examples/mygenpass.c: ...here. * crypt/examples/testpass.c: Moved to... * manual/examples/testpass.c: ...here. * manual/Makefile (chapters): Add crypt. * manual/conf.texi: Add usual header for not-last chapter. * manual/crypt.texi: Add special header for last chapter.
2000-02-29Update.Ulrich Drepper1-0/+412
2000-02-28 Ulrich Drepper <drepper@redhat.com> * crypt/tcrypt.texi: Moved to... * manual/crypt.texi: ...here.