From mboxrd@z Thu Jan 1 00:00:00 1970 From: AKASHI Takahiro Date: Wed, 18 Sep 2019 11:35:19 +0900 Subject: [U-Boot] [RFC 2/3] lib: rsa: generate additional parameters for public key In-Reply-To: References: <20190906070808.1198-1-takahiro.akashi@linaro.org> <20190906070808.1198-3-takahiro.akashi@linaro.org> Message-ID: <20190918023518.GA4398@linaro.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Simon, On Mon, Sep 16, 2019 at 10:48:05PM -0700, Simon Glass wrote: > Hi AKASHI, > > On Fri, 6 Sep 2019 at 00:05, AKASHI Takahiro wrote: > > > > In the current implementation of FIT_SIGNATURE, five parameters for > > a RSA public key are required while only two of them are essential. > > (See rsa-mod-exp.h and uImage.FIT/signature.txt) > > This is a result of considering relatively limited computer power > > and resources on embedded systems, while such a assumption may not > > be quite practical for other use cases. > > > > In this patch, added is a function, rsa_gen_key_prop(), which will > > generate additional parameters for other uses, in particular > > UEFI secure boot, on the fly. > > > > Note: the current code uses some "big number" routines from BearSSL > > for the calculation. > > > > Signed-off-by: AKASHI Takahiro > > --- > > include/u-boot/rsa-mod-exp.h | 3 + > > lib/rsa/Makefile | 2 +- > > lib/rsa/rsa-keyprop.c | 631 +++++++++++++++++++++++++++++++++++ > > 3 files changed, 635 insertions(+), 1 deletion(-) > > create mode 100644 lib/rsa/rsa-keyprop.c > > > > diff --git a/include/u-boot/rsa-mod-exp.h b/include/u-boot/rsa-mod-exp.h > > index 8a428c4b6a1a..ca189292d869 100644 > > --- a/include/u-boot/rsa-mod-exp.h > > +++ b/include/u-boot/rsa-mod-exp.h > > @@ -26,6 +26,9 @@ struct key_prop { > > uint32_t exp_len; /* Exponent length in number of uint8_t */ > > }; > > > > +struct key_prop *rsa_gen_key_prop(const void *key, uint32_t keylen); > > +void rsa_free_key_prop(struct key_prop *prop); > > + > > /** > > * rsa_mod_exp_sw() - Perform RSA Modular Exponentiation in sw > > * > > diff --git a/lib/rsa/Makefile b/lib/rsa/Makefile > > index 226d8f3514a9..d66eef74c514 100644 > > --- a/lib/rsa/Makefile > > +++ b/lib/rsa/Makefile > > @@ -5,5 +5,5 @@ > > # (C) Copyright 2000-2007 > > # Wolfgang Denk, DENX Software Engineering, wd at denx.de. > > > > -obj-$(CONFIG_RSA_VERIFY) += rsa-verify.o rsa-checksum.o > > +obj-$(CONFIG_RSA_VERIFY) += rsa-verify.o rsa-checksum.o rsa-keyprop.o > > Can this code only be included when needed? It seems a bit large, Okay, compiled in only if CONFIG_RSA_VERIFY_WITH_PKEY. > > obj-$(CONFIG_RSA_SOFTWARE_EXP) += rsa-mod-exp.o > > diff --git a/lib/rsa/rsa-keyprop.c b/lib/rsa/rsa-keyprop.c > > new file mode 100644 > > index 000000000000..e650a931dff9 > > --- /dev/null > > +++ b/lib/rsa/rsa-keyprop.c > > @@ -0,0 +1,631 @@ > > +// SPDX-License-Identifier: GPL-2.0+ > > +/* > > + * RSA library - generate parameters for a public key > > + * > > + * Copyright (c) 2019 Linaro Limited > > + * Author: AKASHI Takahiro > > + * > > + * Big number routines in this file come from BearSSL. > > + * See the original copyright below. > > + * > > + * Copyright (c) 2016 Thomas Pornin > > + * > > + * Permission is hereby granted, free of charge, to any person obtaining > > Can you use SPDX? I'm not sure this license is listed in SPDX, but will ask the author. > > + * a copy of this software and associated documentation files (the > > + * "Software"), to deal in the Software without restriction, including > > + * without limitation the rights to use, copy, modify, merge, publish, > > + * distribute, sublicense, and/or sell copies of the Software, and to > > + * permit persons to whom the Software is furnished to do so, subject to > > + * the following conditions: > > + * > > + * The above copyright notice and this permission notice shall be > > + * included in all copies or substantial portions of the Software. > > + * > > + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, > > + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF > > + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND > > + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS > > + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN > > + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN > > + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE > > + * SOFTWARE. > > + */ > > +#include > > Should this include common.h? Okay. > > + > > +#include > > +#include > > +#include > > Hmm this seems to be for running on the host? rsa.h? No. It was imported from linux kernel to use rsa_parse_pub_key() in rsa_gen_key_prop(). Thanks, -Takahiro Akashi > Regards, > Simon