diff options
| -rw-r--r-- | README.rst | 47 | ||||
| -rwxr-xr-x | git-remote-gcrypt | 135 |
2 files changed, 110 insertions, 72 deletions
@@ -44,18 +44,15 @@ Quickstart git remote add cryptremote gcrypt::rsync://example.com:repo git push cryptremote master > gcrypt: Setting up new repository - > gcrypt: Repository URL is gcrypt::rsync://example.com:repo#KNBr0wKzct52 - > gcrypt: (configuration for cryptremote updated) + > gcrypt: Repository ID is :SHA256:3a29d035adf234af7e[... ] > [ more lines .. ] > To gcrypt::[...] > * [new branch] master -> master -* Share the updated Repository URL with all participants. - -(The generated Repository URL is not secret, it only exists to ensure -that two repositories signed by the same user can not be maliciously -switched around. It incidentally allows multiple repositories to all -share location.) +(The generated Repository id is not secret, it only exists to ensure +that two repositories signed by the same user can be distinguished. +You will see a warning if the remote repository ID changes, which will +only happen if the remote was re-created or switched out.) Design Goals ............ @@ -98,10 +95,12 @@ Examples How to use a git backend:: # notice that the target repo must already exist and its - # `master` branch will be overwritten! - git remote add gitcrypt gcrypt::git@example.com:repo + # `next` branch will be overwritten! + git remote add gitcrypt gcrypt::git@example.com:repo#next git push gitcrypt HEAD +The URL fragment (`#next` here) indicates which branch is used. + Notes ===== @@ -112,20 +111,20 @@ Repository Format EncSign(X) is sign+encrypt to a PGP key holder Encrypt(K,X) is symmetric encryption - Hash(X) is SHA-224 + Hash(X) is SHA-256 B: branch list L: list of the hash (Hi) and key (Ki) for each packfile - R: Hash(Repository ID) + R: repository id - Store Manifest as EncSign(B || L || R) in filename R + Store Manifest as EncSign(B || L || R) Store each packfile P as P' = Encrypt(Ki, P) in filename Hi where Hi = Hash(P') and Ki is a random string To read the repository decrypt+verify Manifest using private key -> (B, L, R) - verify R matches Hash(Requested Repository ID) + warn if R does not match saved repository id for this remote for Hi, Ki in L: download file Hi from the server -> P' verify Hash(P') matches Hi @@ -138,14 +137,13 @@ Manifest file :: - $ gpg -d < 5a191cea8c1021a95d813c4007c14f2cc987a40880c2f669430f1916 - b4a4a39365d19282810c19d0f3f24d04dd2d179f refs/tags/version1 - 1d323ddadf4cf1d80fced447e637ab3766b168b7 refs/heads/master - pack :SHA224:cfdf36515e0d0820554fe5fd9f00a4bee17bcf88ec8a752d851c46ee \ - Rc+j8Nv6GOW3mBhWOx6W6jjz3BTX7B6XIJ6RYI+P4TEy - pack :SHA224:a43ccd208d3bd2ea582dbd5407cb8ed6e18b150b1da25c806115eaa5 \ - UXR3/R7awFCUJWYdzXzrlkk7E2Acxq/Y4EfEcd62AwGG - repo :SHA224:5a191cea8c1021a95d813c4007c14f2cc987a40880c2f669430f1916 1 + $ gpg -d 91bd0c092128cf2e60e1a608c31e92caf1f9c1595f83f2890ef17c0e4881aa0a + 542051c7cd152644e4995bda63cc3ddffd635958 refs/heads/next + 3c9e76484c7596eff70b21cbe58408b2774bedad refs/heads/master + pack :SHA256:f2ad50316fbca42c553810aec3709c24974585ec1b34aae77d5cd4ba67092dc4 z8YoAnFpMlWPIYG8wo1adewd4Fp7Fo3PkI2mND49P1qm + pack :SHA256:a6e17bb4c042bdfa8e38856ee6d058d0c0f0c575ace857c4795426492f379584 82+k2cbiUn7i2cW0dgXfyX6wXGpvVaQGj5sF59Y8my5W + keep :SHA256:f2ad50316fbca42c553810aec3709c24974585ec1b34aae77d5cd4ba67092dc4 1 + repo :SHA256:ef8e52a7ea96761f713c14caa7190b5f3b55ff87ffe091cab40f7cbe1d3b5b96 Each item extends until newline, and matches one of the following forms: @@ -158,8 +156,8 @@ Each item extends until newline, and matches one of the following forms: `keep :<hashtype>:<hash> <generation>` Packfile hash and its repack generation - `repo :<hashtype>:<hash> <version>` - The hash of the repository id. + `repo :<hashtype>:<hash>` + The repository id `extn <name> ...` Extension field, preserved but unused. @@ -168,7 +166,6 @@ Each item extends until newline, and matches one of the following forms: Yet to be Implemented ..................... -+ Repacking the remote repository + Some kind of simple keyring management See Also diff --git a/git-remote-gcrypt b/git-remote-gcrypt index 19565ac..98c8ee6 100755 --- a/git-remote-gcrypt +++ b/git-remote-gcrypt @@ -16,9 +16,10 @@ Gref="refs/gcrypt/gitception$GITCEPTION" Gref_rbranch="refs/heads/master" Repoid= Packkey_bytes=33 # 33 random bytes for passphrase, still compatible if changed -Hashtype=SHA224 # incompatible if changed -Packpfx="pack :${Hashtype}:" -Keeppfx="keep :${Hashtype}:" +Hashtype=SHA256 # SHA512 SHA384 SHA256 SHA224 supported. +Packpat="pack :*:" +Manifestfile=91bd0c092128cf2e60e1a608c31e92caf1f9c1595f83f2890ef17c0e4881aa0a +Urlfrag= Branchlist= Packlist= @@ -68,7 +69,7 @@ splitcolon() prefix_=${1%%:*} suffix_=${1#*:} } -repoidstr() { xecho "repo :${Hashtype}:$Repoid 1"; } +repoidstr() { xecho "repo $Repoid"; } ## gitception part # Fetch giturl $1, file $2 @@ -77,7 +78,7 @@ gitception_get() # Take care to preserve FETCH_HEAD local ret_=: obj_id= f_head="$GIT_DIR/FETCH_HEAD" [ -e "$f_head" ] && command mv -f "$f_head" "$f_head.$$~" || : - git fetch -q -f "$1" "$Gref_rbranch:$Gref" 2>/dev/tty >/dev/null && + git fetch -q -f "$1" "refs/heads/${Urlfrag:-master}:$Gref" 2>/dev/tty >/dev/null && obj_id="$(git ls-tree "$Gref" | xgrep -E '\b'"$2"'$' | awk '{print $3}')" && isnonnull "$obj_id" && git cat-file blob "$obj_id" && ret_=: || { ret_=false && : ; } @@ -180,7 +181,8 @@ PUT_FINAL() then : else - git push --quiet -f "${1#gitception://}" "$Gref:$Gref_rbranch" + git push --quiet -f "${1#gitception://}" \ + "$Gref:refs/heads/${Urlfrag:-master}" fi } @@ -285,14 +287,17 @@ genkey() gpg --armor --gen-rand 1 "$1" } -pack_hash() +gpg_hash() { local hash_= - hash_=$(gpg --with-colons --print-md "$Hashtype" | tr A-F a-f) + hash_=$(gpg --with-colons --print-md "$1" | tr A-F a-f) hash_=${hash_#:*:} xecho "${hash_%:}" } +pack_hash() { gpg_hash "$Hashtype"; } + + # Pass the branch/ref by pipe to git safe_git_rev_parse() { @@ -306,19 +311,15 @@ make_new_repo() echo_info "Setting up new repository" PUTREPO "$URL" - # We need a relatively short ID for URL+REPO - # The manifest will be stored at pack_hash($urlid_) - # Needed assumption: the same user should have no duplicate urlid_ - # For now, we arbitrarily use 9 random bytes (72 bits) - urlid_=$(genkey 9 | tr '+/' '-_') - Repoid=$(xecho_n "$urlid_" | pack_hash) + # Needed assumption: the same user should have no duplicate Repoid + Repoid=":${Hashtype}:$(genkey 64 | pack_hash)" iseq "${NAME#gcrypt::}" "$URL" || { - git config "remote.$NAME.url" "gcrypt::$URL#$urlid_" + git config "remote.$NAME.gcrypt-id" "$Repoid" fix_config=1 } - echo_info "Repository URL is" "gcrypt::$URL#$urlid_" + echo_info "Repository ID is $Repoid" Extension_list=$(xecho "extn comment") - isnull "$fix_config" || echo_info "(configuration for $NAME updated)" + #isnull "$fix_config" || echo_info "(configuration for $NAME updated)" } @@ -365,7 +366,7 @@ read_config() ensure_connected() { - local manifest_= rcv_repoid= url_id= + local manifest_= rcv_repoid= r_name= if isnonnull "$Did_find_repo" then @@ -374,24 +375,36 @@ ensure_connected() Did_find_repo=no read_config + iseq "${NAME#gcrypt::}" "$URL" || r_name=$NAME + # Fixup ssh:// -> rsync:// if isurl ssh "$URL"; then URL="rsync://${URL#ssh://}" fi - # split out Repo ID from URL - url_id=${URL##*"#"} - isnoteq "$url_id" "$URL" || { - url_id=${URL##*/"G."} - isnoteq "$url_id" "$URL" || return 0 - URL=${URL%/"G.$url_id"} + # Find the URL fragment + Urlfrag=${URL##*"#"} + isnoteq "$Urlfrag" "$URL" || Urlfrag= + URL=${URL%"#$Urlfrag"} + + # manifestfile -- sha224 hash if we can, else the default location + if isurl sftp "$URL" || islocalrepo "$URL" || isurl rsync "$URL" + then + # not for gitception + isnull "$Urlfrag" || Manifestfile=$(xecho_n "$Urlfrag" | gpg_hash SHA224) + fi + + Repoid= + isnull "$r_name" || { + Repoid=$(git config "remote.$r_name.gcrypt-id" || :) } - URL=${URL%"#$url_id"} - Repoid=$(xecho_n "$url_id" | pack_hash) + TmpManifest_Enc="$Localdir/tmp_manifest.$$" - GET "$URL" "$Repoid" "$TmpManifest_Enc" 2>/dev/null || - echo_die "Repository not found: $url_id at $URL" + GET "$URL" "$Manifestfile" "$TmpManifest_Enc" 2>/dev/null || { + echo_info "Repository not found: $URL" + return 0 + } Did_find_repo=yes echo_info "Decrypting manifest" @@ -401,21 +414,50 @@ ensure_connected() rm -f "$TmpManifest_Enc" Branchlist=$(xecho "$manifest_" | xgrep -E '^[0-9a-f]{40} ') - Packlist=$(xecho "$manifest_" | xgrep "^$Packpfx") - Keeplist=$(xecho "$manifest_" | xgrep "^keep") + Packlist=$(xecho "$manifest_" | xgrep "^pack ") + Keeplist=$(xecho "$manifest_" | xgrep "^keep ") Extension_list=$(xecho "$manifest_" | xgrep "^extn ") rcv_repoid=$(xecho "$manifest_" | xgrep "^repo ") - iseq "$(repoidstr)" "$rcv_repoid" || echo_die "Repository id mismatch!" + + rcv_repoid=${rcv_repoid#repo } + rcv_repoid=${rcv_repoid% *} + if isnull "$Repoid" + then + echo_info "Remote repo ID is $rcv_repoid" + Repoid=$rcv_repoid + elif isnoteq "$rcv_repoid" "$Repoid" + then + echo_info "WARNING:" + echo_info "WARNING: Remote repository ID has changed!" + echo_info "WARNING: to $rcv_repoid" + echo_info "WARNING:" + Repoid=$rcv_repoid + else + return 0 + fi + + isnull "$r_name" || { + git config "remote.$r_name.gcrypt-id" "$rcv_repoid" + } } fetch_decrypt_pack() { - local key_= rcv_id= - GET "$URL" "$1" "$TmpPack_Encrypted" && - rcv_id=$(pack_hash < "$TmpPack_Encrypted") && - iseq "$rcv_id" "$1" || - echo_die "Packfile $1 does not match digest!" - key_=$(xecho "$Packlist" | grep "$1" | cut -f 3 -d ' ') + local key_= rcv_id= htype_= pack_= hfunc_= + splitcolon "${1#pack :}" + htype_=$prefix_ + pack_=$suffix_ + + if isnoteq "$htype_" SHA256 && isnoteq "$htype_" SHA224 && + isnoteq "$htype_" SHA384 && isnoteq "$htype_" SHA512 + then + echo_die "Packline malformed: $1" + fi + GET "$URL" "$pack_" "$TmpPack_Encrypted" && + rcv_id=$(gpg_hash "$htype_" < "$TmpPack_Encrypted") && + iseq "$rcv_id" "$pack_" || + echo_die "Packfile $pack_ does not match digest!" + key_=$(xecho "$Packlist" | grep "$pack_" | cut -f 3 -d ' ') DECRYPT "$key_" < "$TmpPack_Encrypted" } @@ -462,8 +504,8 @@ repack_if_needed() then continue fi - pack_=${packline_#"$Packpfx"} - fetch_decrypt_pack "$pack_" | + pack_=${packline_#$Packpat} + fetch_decrypt_pack "$packline_" | git index-pack -v --stdin "$Localdir/pack/${pack_}.pack" >/dev/null done key_=$(genkey "$Packkey_bytes") @@ -483,8 +525,8 @@ repack_if_needed() fi pack_id=$(pack_hash < "$TmpPack_Encrypted") - Packlist=$(append "$Packlist" "$Packpfx$pack_id $key_") - Keeplist=$(append "$Keeplist" "$Keeppfx$pack_id 1") + Packlist=$(append "$Packlist" "pack :${Hashtype}:$pack_id $key_") + Keeplist=$(append "$Keeplist" "keep :${Hashtype}:$pack_id 1") rm -r -f "$Localdir/pack" did_repack=yes } @@ -542,11 +584,10 @@ do_fetch() xecho "$pneed_" | while read packline_ do isnonnull "$packline_" || continue - pack_=${packline_#"$Packpfx"} - fetch_decrypt_pack "$pack_" | + fetch_decrypt_pack "$packline_" | git index-pack -v --stdin >/dev/null # add to local pack list - xecho "$Packpfx$pack_" >> "$Localdir/have_packs$GITCEPTION" + xecho "${packline_}" >> "$Localdir/have_packs$GITCEPTION" done rm -f "$TmpPack_Encrypted" @@ -614,7 +655,7 @@ EOF if isnoteq "$did_repack" yes then - Packlist=$(append "$Packlist" "$Packpfx$pack_id $key_") + Packlist=$(append "$Packlist" "pack :${Hashtype}:$pack_id $key_") fi # else, repack rewrote Packlist @@ -639,14 +680,14 @@ EOF rm -f "$TmpObjlist" # Upload manifest - PUT "$URL" "$Repoid" "$TmpManifest_Enc" + PUT "$URL" "$Manifestfile" "$TmpManifest_Enc" # Delete packs if isnonnull "$Packlist_delete"; then REMOVE "$URL" "$(xecho "$Packlist_delete" | while read packline_ do isnonnull "$packline_" || continue - pack_=${packline_#"$Packpfx"} + pack_=${packline_#$Packpat} xecho "$pack_" done)" fi |