Re: base-apt signing interface could be improved

[vijaikumar.kanagarajan@gmail.com]

[-- Attachment #1.1: Type: text/plain, Size: 7284 bytes --]



On Monday, June 17, 2019 at 4:49:58 PM UTC+5:30, Henning Schild wrote:
>
> Am Fri, 14 Jun 2019 06:50:58 -0700 
> schrieb "Amy_...@mentor.com <javascript:>" <amy.f...@gmail.com 
> <javascript:>>: 
>
> > 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. 
>

>From reprepro manual:

SignWith
When this field is present, a Release.gpg file will be generated. If the 
value is "yes" or "default", the default key of gpg is used.

Reference: https://manpages.debian.org/stretch/reprepro/reprepro.1.en.html 

So I guess it would not be signed by all the keys instead just with the 
default key.

Thanks,
Vijai Kumar K


> 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_...@mentor.com <javascript:>> 
> > 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_...@mentor.com <javascript:>> 
> > 
> > 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 
> >   
> > 
>
>

[-- Attachment #1.2: Type: text/html, Size: 15281 bytes --]