| Message ID | 1544027592-35204-2-git-send-email-matthew.weber@rockwellcollins.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [1/2] system cfg: default mkpasswd to SHA | expand |
Matt, All, On 2018-12-05 10:33 -0600, Matt Weber spake thusly: > As SHA256 is now default, removing weak MD5 option. C libraries now > all support the SHA methods. > glibc 2.7+ > uclibc (bdd8362a88 package/uclibc: defconfig: enable sha-256...) > musl 1.1.14+ > > One issue this would prevent is a host tool issue with a FIPS enabled > system where weak ciphers/methods are disabled. The crypt(3) call > checks /proc/sys/crypto/fips_enabled and would result in mkpasswd > returning "crypt failed." Rather then create a host dependency check > this patch removes the potential issue. > > Cc: Yann E. MORIN <yann.morin.1998@free.fr> > Signed-off-by: Matthew Weber <matthew.weber@rockwellcollins.com> Acked-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Regards, Yann E. MORIN. > --- > Config.in.legacy | 8 ++++++++ > system/Config.in | 10 ---------- > 2 files changed, 8 insertions(+), 10 deletions(-) > > diff --git a/Config.in.legacy b/Config.in.legacy > index 02321c8..d70654c 100644 > --- a/Config.in.legacy > +++ b/Config.in.legacy > @@ -143,6 +143,14 @@ comment "----------------------------------------------------" > endif > > ############################################################################### > + > +config BR2_TARGET_GENERIC_PASSWD_MD5 > + bool "target passwd md5 format support has been removed" > + select BR2_LEGACY > + help > + The default has been moved to SHA256 and all C libraries > + now support that method by default > + > comment "Legacy options removed in 2018.11" > > config BR2_TARGET_XLOADER > diff --git a/system/Config.in b/system/Config.in > index 2123d33..9a87b1b 100644 > --- a/system/Config.in > +++ b/system/Config.in > @@ -68,16 +68,6 @@ choice > > Note: this is used at build-time, and *not* at runtime. > > -config BR2_TARGET_GENERIC_PASSWD_MD5 > - bool "md5" > - help > - Use MD5 to encode passwords. > - > - The default. Wildly available, and pretty good. > - Although pretty strong, MD5 is now an old hash function, and > - suffers from some weaknesses, which makes it susceptible to > - brute-force attacks. > - > config BR2_TARGET_GENERIC_PASSWD_SHA256 > bool "sha-256" > help > -- > 1.9.1 >
On Wed, Dec 5, 2018 at 10:33 AM Matt Weber <matthew.weber@rockwellcollins.com> wrote: > > As SHA256 is now default, removing weak MD5 option. C libraries now > all support the SHA methods. > glibc 2.7+ > uclibc (bdd8362a88 package/uclibc: defconfig: enable sha-256...) > musl 1.1.14+ > > One issue this would prevent is a host tool issue with a FIPS enabled > system where weak ciphers/methods are disabled. The crypt(3) call > checks /proc/sys/crypto/fips_enabled and would result in mkpasswd > returning "crypt failed." Rather then create a host dependency check > this patch removes the potential issue. A little more research has me changing the reasoning a bit. This actually makes more sense. Our host/bin/mkpasswd uses the host systems PAM "sufficient algorithm" rules when creating the password. (https://www.stigviewer.com/stig/red_hat_enterprise_linux_6/2016-06-05/finding/V-38574) It just so happens the system we were looking at this issue on was also configured for other FIPS related desired cipher/hashes. > > Cc: Yann E. MORIN <yann.morin.1998@free.fr> > Signed-off-by: Matthew Weber <matthew.weber@rockwellcollins.com> > --- > Config.in.legacy | 8 ++++++++ > system/Config.in | 10 ---------- > 2 files changed, 8 insertions(+), 10 deletions(-) > > diff --git a/Config.in.legacy b/Config.in.legacy > index 02321c8..d70654c 100644 > --- a/Config.in.legacy > +++ b/Config.in.legacy > @@ -143,6 +143,14 @@ comment "----------------------------------------------------" > endif > > ############################################################################### > + > +config BR2_TARGET_GENERIC_PASSWD_MD5 > + bool "target passwd md5 format support has been removed" > + select BR2_LEGACY > + help > + The default has been moved to SHA256 and all C libraries > + now support that method by default > + > comment "Legacy options removed in 2018.11" > > config BR2_TARGET_XLOADER > diff --git a/system/Config.in b/system/Config.in > index 2123d33..9a87b1b 100644 > --- a/system/Config.in > +++ b/system/Config.in > @@ -68,16 +68,6 @@ choice > > Note: this is used at build-time, and *not* at runtime. > > -config BR2_TARGET_GENERIC_PASSWD_MD5 > - bool "md5" > - help > - Use MD5 to encode passwords. > - > - The default. Wildly available, and pretty good. > - Although pretty strong, MD5 is now an old hash function, and > - suffers from some weaknesses, which makes it susceptible to > - brute-force attacks. > - > config BR2_TARGET_GENERIC_PASSWD_SHA256 > bool "sha-256" > help > -- > 1.9.1 >
All, On Wed, Dec 5, 2018 at 7:08 PM Matthew Weber <matthew.weber@rockwellcollins.com> wrote: > > On Wed, Dec 5, 2018 at 10:33 AM Matt Weber > <matthew.weber@rockwellcollins.com> wrote: > > > > As SHA256 is now default, removing weak MD5 option. C libraries now > > all support the SHA methods. > > glibc 2.7+ > > uclibc (bdd8362a88 package/uclibc: defconfig: enable sha-256...) > > musl 1.1.14+ > > > > One issue this would prevent is a host tool issue with a FIPS enabled > > system where weak ciphers/methods are disabled. The crypt(3) call > > checks /proc/sys/crypto/fips_enabled and would result in mkpasswd > > returning "crypt failed." Rather then create a host dependency check > > this patch removes the potential issue. > > A little more research has me changing the reasoning a bit. This > actually makes more sense. Our host/bin/mkpasswd uses the host > systems PAM "sufficient algorithm" rules when creating the password. > (https://www.stigviewer.com/stig/red_hat_enterprise_linux_6/2016-06-05/finding/V-38574) > It just so happens the system we were looking at this issue on was > also configured for other FIPS related desired cipher/hashes. Oops that doesn't seem to be valid for mkpasswd. just passwd. I'll refresh my description when I split the first patch. > > > > > Cc: Yann E. MORIN <yann.morin.1998@free.fr> > > Signed-off-by: Matthew Weber <matthew.weber@rockwellcollins.com> > > --- > > Config.in.legacy | 8 ++++++++ > > system/Config.in | 10 ---------- > > 2 files changed, 8 insertions(+), 10 deletions(-) > > > > diff --git a/Config.in.legacy b/Config.in.legacy > > index 02321c8..d70654c 100644 > > --- a/Config.in.legacy > > +++ b/Config.in.legacy > > @@ -143,6 +143,14 @@ comment "----------------------------------------------------" > > endif > > > > ############################################################################### > > + > > +config BR2_TARGET_GENERIC_PASSWD_MD5 > > + bool "target passwd md5 format support has been removed" > > + select BR2_LEGACY > > + help > > + The default has been moved to SHA256 and all C libraries > > + now support that method by default > > + > > comment "Legacy options removed in 2018.11" > > > > config BR2_TARGET_XLOADER > > diff --git a/system/Config.in b/system/Config.in > > index 2123d33..9a87b1b 100644 > > --- a/system/Config.in > > +++ b/system/Config.in > > @@ -68,16 +68,6 @@ choice > > > > Note: this is used at build-time, and *not* at runtime. > > > > -config BR2_TARGET_GENERIC_PASSWD_MD5 > > - bool "md5" > > - help > > - Use MD5 to encode passwords. > > - > > - The default. Wildly available, and pretty good. > > - Although pretty strong, MD5 is now an old hash function, and > > - suffers from some weaknesses, which makes it susceptible to > > - brute-force attacks. > > - > > config BR2_TARGET_GENERIC_PASSWD_SHA256 > > bool "sha-256" > > help > > -- > > 1.9.1 > > > > > -- > > Matthew Weber | Pr. Software Engineer | Commercial Avionics > > COLLINS AEROSPACE > > 400 Collins Road NE, Cedar Rapids, Iowa 52498, USA > > Tel: +1 319 295 7349 | FAX: +1 319 263 6099 > > matthew.weber@collins.com | collinsaerospace.com > > > > CONFIDENTIALITY WARNING: This message may contain proprietary and/or > privileged information of Collins Aerospace and its affiliated > companies. If you are not the intended recipient, please 1) Do not > disclose, copy, distribute or use this message or its contents. 2) > Advise the sender by return email. 3) Delete all copies (including all > attachments) from your computer. Your cooperation is greatly > appreciated.
diff --git a/Config.in.legacy b/Config.in.legacy index 02321c8..d70654c 100644 --- a/Config.in.legacy +++ b/Config.in.legacy @@ -143,6 +143,14 @@ comment "----------------------------------------------------" endif ############################################################################### + +config BR2_TARGET_GENERIC_PASSWD_MD5 + bool "target passwd md5 format support has been removed" + select BR2_LEGACY + help + The default has been moved to SHA256 and all C libraries + now support that method by default + comment "Legacy options removed in 2018.11" config BR2_TARGET_XLOADER diff --git a/system/Config.in b/system/Config.in index 2123d33..9a87b1b 100644 --- a/system/Config.in +++ b/system/Config.in @@ -68,16 +68,6 @@ choice Note: this is used at build-time, and *not* at runtime. -config BR2_TARGET_GENERIC_PASSWD_MD5 - bool "md5" - help - Use MD5 to encode passwords. - - The default. Wildly available, and pretty good. - Although pretty strong, MD5 is now an old hash function, and - suffers from some weaknesses, which makes it susceptible to - brute-force attacks. - config BR2_TARGET_GENERIC_PASSWD_SHA256 bool "sha-256" help
As SHA256 is now default, removing weak MD5 option. C libraries now all support the SHA methods. glibc 2.7+ uclibc (bdd8362a88 package/uclibc: defconfig: enable sha-256...) musl 1.1.14+ One issue this would prevent is a host tool issue with a FIPS enabled system where weak ciphers/methods are disabled. The crypt(3) call checks /proc/sys/crypto/fips_enabled and would result in mkpasswd returning "crypt failed." Rather then create a host dependency check this patch removes the potential issue. Cc: Yann E. MORIN <yann.morin.1998@free.fr> Signed-off-by: Matthew Weber <matthew.weber@rockwellcollins.com> --- Config.in.legacy | 8 ++++++++ system/Config.in | 10 ---------- 2 files changed, 8 insertions(+), 10 deletions(-)