Re: base-apt signing interface could be improved

[Henning Schild <henning.schild@siemens.com>]

Am Fri, 14 Jun 2019 06:50:58 -0700
schrieb "Amy_Fong@mentor.com" <amy.fong.3142@gmail.com>:

> On Friday, 14 June 2019 04:23:00 UTC-4, Henning Schild wrote:
> >
> > Am Thu, 13 Jun 2019 09:55:29 -0700 
> > schrieb "Amy_...@mentor.com <javascript:>" <amy.f...@gmail.com 
> > <javascript:>>: 
> >  
> > > On Thursday, 6 June 2019 09:46:02 UTC-4, Henning Schild wrote:   
> > > > 
> > > > Hi, 
> > > > 
> > > > i just had a quick look at the implementation of the base-apt 
> > > > signing for the first time. The interface is not ideal and has 
> > > > potential for the signing key and the checking key not actually 
> > > > belonging together. 
> > > > 
> > > > As far as i understand the code i read, Isar will start signing 
> > > > base-apt if BASE_REPO_KEY is set to anything. The private key
> > > > it will use to sign the repo is not specified at all, it will
> > > > be whatever gnupg defaults to, given its configuration. 
> > > > 
> > > > I would suggest to switch from "SignWith yes" to "SignWith 
> > > > <keyid>", and derive the id from BASE_REPO_KEY. 
> > > > 
> > > > Further improvements would be to actually configure gnupg
> > > > inside Isar and not rely on an outside configuration. Relying
> > > > on the outside config means that all (multi)configs will have
> > > > to use the same keypair. So we would add 
> > > > 
> > > > BASE_REPO_KEY_PRIVATE and ..._PASSPHRASE 
> > > > 
> > > > Now we would create a new gpg homedir next to where we store 
> > > > base-apt. We would import that one key there and potentially
> > > > unlock it with its passphrase. If we clean and rebuild we get a
> > > > working gpghome for sure. 
> > > > 
> > > > Henning 
> > > >     
> > > 
> > > Hi, 
> > > 
> > > Perhaps something like the following ... 
> > > 
> > > Of course, since BASE_REPO_KEY permits specifying 
> > > multiple keys, this raises a question of which keyid?   
> >
> > Oh that is a nice hidden feature, indeed one can specify multiple
> > keys there. So that variable should be called BASE_REPO_KEYS
> > instead. 
> >
> > And yes reprepro also supports multiple values. So i guess your
> > patch is correct and it would probably sign the repo with all the
> > keys specified. 
> >
> > Whether that is what we want is another question, and i am not sure 
> > whether "yes" will also use all keys or just the default one. 
> >  
> > > Amy 
> > > 
> > > From 5ceb4a2ef97bc7fa6c44cd9ce6f73f9a831773f3 Mon Sep 17 00:00:00
> > > 2001 From: Amy Fong <Amy_...@mentor.com <javascript:>> 
> > > Date: Thu, 13 Jun 2019 12:52:06 -0400 
> > > Subject: [PATCH] base-apt: Use BASE_REPO_KEY for signing 
> > > 
> > > Extract keyid from BASE_REPO_KEY for signing 
> > > 
> > > Signed-off-by: Amy Fong <Amy_...@mentor.com <javascript:>> 
> > > --- 
> > >  meta/recipes-devtools/base-apt/base-apt.bb | 9 ++++++++- 
> > >  1 file changed, 8 insertions(+), 1 deletion(-) 
> > > 
> > > diff --git a/meta/recipes-devtools/base-apt/base-apt.bb 
> > > b/meta/recipes-devtools/base-apt/base-apt.bb 
> > > index 1c0b4c6..81245f7 100644 
> > > --- a/meta/recipes-devtools/base-apt/base-apt.bb 
> > > +++ b/meta/recipes-devtools/base-apt/base-apt.bb 
> > > @@ -19,8 +19,15 @@ do_cache_config() { 
> > >          sed -e "s#{CODENAME}#"${BASE_DISTRO_CODENAME}"#g" \ 
> > >              ${WORKDIR}/distributions.in > 
> > > ${CACHE_CONF_DIR}/distributions if [ "${BASE_REPO_KEY}" ] ; then 
> > > +            option="yes"   
> >
> > maybe there is a better name for the variable? 
> >
> > Henning 
> >  
> > > +            for key in ${BASE_REPO_KEY}; do 
> > > +                keyid=$(wget -qO - $key | gpg --keyid-format
> > > 0xlong --with-colons - 2>/dev/null |grep "^pub:" |awk -F':'
> > > '{print $5;}') 
> > > +                if [ -n "$keyid" ]; then 
> > > +                    option="$keyid" 
> > > +                fi 
> > > +            done 
> > >              # To generate Release.gpg 
> > > -            echo "SignWith: yes" >>
> > > ${CACHE_CONF_DIR}/distributions 
> > > +            echo "SignWith: $option" >> 
> > > ${CACHE_CONF_DIR}/distributions fi 
> > >      fi 
> > >     
> >  
> 
> How about BASE_REPO_SIGN_KEY?

I do not understand what you are trying to solve with changing that
name and going back to one-key-only, after you have found that
BASE_REPO_KEY is indeed an array and reprepro also accepts an array.

Now we need to know what "yes", compared to the array.

And any tiny patch like this one, without a proper commit message and
description, is not going to lead anywhere good.

You guys are doing the full story. kas, signed base-apt, multiple keys,
agent-forwarding ...
After you are done you should have a clear picture of what currently
does not work as expected, and how it can be fixes (your initial
implementation).
We can then discuss that implementation and incorporate a full patch
series including docs into kas and Isar.

> commit 42ee1139e8383fc27e7d98be522cb4d306fd170c (HEAD -> apt_sign)
> Author: Amy Fong <Amy_Fong@mentor.com>
> Date:   Thu Jun 13 12:52:06 2019 -0400
> 
>     base-apt: Use BASE_REPO_SIGN_KEY for signing
>     
>     Extract keyid from BASE_REPO_SIGN_KEY for signing
>     
>     Signed-off-by: Amy Fong <Amy_Fong@mentor.com>
> 
> diff --git a/meta/recipes-devtools/base-apt/base-apt.bb 
> b/meta/recipes-devtools/base-apt/base-apt.bb
> index 1c0b4c6..c896add 100644
> --- a/meta/recipes-devtools/base-apt/base-apt.bb
> +++ b/meta/recipes-devtools/base-apt/base-apt.bb
> @@ -18,9 +18,14 @@ do_cache_config() {
>      if [ ! -e "${CACHE_CONF_DIR}/distributions" ]; then
>          sed -e "s#{CODENAME}#"${BASE_DISTRO_CODENAME}"#g" \
>              ${WORKDIR}/distributions.in >
> ${CACHE_CONF_DIR}/distributions
> -        if [ "${BASE_REPO_KEY}" ] ; then
> +        if [ "${BASE_REPO_SIGN_KEY}" ] ; then
> +            option="yes"
> +            keyid=$(wget -qO - "${BASE_REPO_SIGN_KEY}" | gpg 

Using wget, but that is most likely a "file:///" URI. And whenever you
do networking in a task, you need to take care of proxies.

Henning

> --keyid-format 0xlong --with-colons - 2>/dev/null |grep "^pub:" |awk
> -F':' '{print $5;}')
> +            if [ -n "$keyid" ]; then
> +                option="$keyid"
> +            fi
>              # To generate Release.gpg
> -            echo "SignWith: yes" >> ${CACHE_CONF_DIR}/distributions
> +            echo "SignWith: $option" >>
> ${CACHE_CONF_DIR}/distributions fi
>      fi
>  
>