plugin-caller: add missing methods from acme.sh

As reported in our community forum [0] certain dns plugins use code
from `acme.sh`, which is currently not in our proxmox-acme.

I initially only added _sign and it's callees, but then though about
trying to get all missing methods somehow (only resethttp() was
missing in addition).

The heuristic used to get all missing methods was grepping for '\b_'
in all dns plugins and then removing:
* declarations in proxmox_acme (already present)
* methods declared in the plugins themselves
* $_.* (or ${_.*) - variable use
* comments

in shell:
```
present=$(awk 'BEGIN{ORS="|";} /^_/{ gsub(/\(\) {/, ""); print $0}' \
  src/proxmox-acme | | sed -r 's/\|$//')
local=$(awk 'BEGIN{ORS="|";} /^_/{ gsub(/\(\) {/, ""); print $0}' \
  src/acme.sh/dnsapi/dns*.sh | sed -r 's/\|$//')
grep '\b_' src/acme.sh/dnsapi/* | grep -Ev \
  "$present|$local|_[a-zA-Z0-9_-]+=|\\$\{?_|^src/acme.sh/dnsapi/.*sh:#"
```

[0] https://forum.proxmox.com/threads/proxmox-acme-with-transip-plugin-_sign-command-not-found.92582/

Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>

diff --git a/src/proxmox-acme b/src/proxmox-acme
index 4d249a7f4f72418087ed4f6d378e60b35a0a19a9..9c55521da77e3dd8900cbbc050c3f792038d1114 100644 (file)
--- a/src/proxmox-acme
+++ b/src/proxmox-acme
@@ -33,6 +33,11 @@ _digest() {
   fi
 }
 
+_usage() {
+  __red "$@" >&2
+  printf "\n" >&2
+}
+
 _upper_case() {
   # shellcheck disable=SC2018,SC2019
   tr 'a-z' 'A-Z'
@@ -108,6 +113,115 @@ _egrep_o() {
   fi
 }
 
+_h2b() {
+  if _exists xxd; then
+    if _contains "$(xxd --help 2>&1)" "assumes -c30"; then
+      if xxd -r -p -c 9999 2>/dev/null; then
+        return
+      fi
+    else
+      if xxd -r -p 2>/dev/null; then
+        return
+      fi
+    fi
+  fi
+
+  hex=$(cat)
+  ic=""
+  jc=""
+  _debug2 _URGLY_PRINTF "$_URGLY_PRINTF"
+  if [ -z "$_URGLY_PRINTF" ]; then
+    if [ "$_ESCAPE_XARGS" ] && _exists xargs; then
+      _debug2 "xargs"
+      echo "$hex" | _upper_case | sed 's/\([0-9A-F]\{2\}\)/\\\\\\x\1/g' | xargs printf
+    else
+      for h in $(echo "$hex" | _upper_case | sed 's/\([0-9A-F]\{2\}\)/ \1/g'); do
+        if [ -z "$h" ]; then
+          break
+        fi
+        printf "\x$h%s"
+      done
+    fi
+  else
+    for c in $(echo "$hex" | _upper_case | sed 's/\([0-9A-F]\)/ \1/g'); do
+      if [ -z "$ic" ]; then
+        ic=$c
+        continue
+      fi
+      jc=$c
+      ic="$(_h_char_2_dec "$ic")"
+      jc="$(_h_char_2_dec "$jc")"
+      printf '\'"$(printf "%o" "$(_math "$ic" \* 16 + $jc)")""%s"
+      ic=""
+      jc=""
+    done
+  fi
+
+}
+
+#Usage: keyfile hashalg
+#Output: Base64-encoded signature value
+_sign() {
+  keyfile="$1"
+  alg="$2"
+  if [ -z "$alg" ]; then
+    _usage "Usage: _sign keyfile hashalg"
+    return 1
+  fi
+
+  _sign_openssl="${ACME_OPENSSL_BIN:-openssl} dgst -sign $keyfile "
+
+  if grep "BEGIN RSA PRIVATE KEY" "$keyfile" >/dev/null 2>&1 || grep "BEGIN PRIVATE KEY" "$keyfile" >/dev/null 2>&1; then
+    $_sign_openssl -$alg | _base64
+  elif grep "BEGIN EC PRIVATE KEY" "$keyfile" >/dev/null 2>&1; then
+    if ! _signedECText="$($_sign_openssl -sha$__ECC_KEY_LEN | ${ACME_OPENSSL_BIN:-openssl} asn1parse -inform DER)"; then
+      _err "Sign failed: $_sign_openssl"
+      _err "Key file: $keyfile"
+      _err "Key content:$(wc -l <"$keyfile") lines"
+      return 1
+    fi
+    _debug3 "_signedECText" "$_signedECText"
+    _ec_r="$(echo "$_signedECText" | _head_n 2 | _tail_n 1 | cut -d : -f 4 | tr -d "\r\n")"
+    _ec_s="$(echo "$_signedECText" | _head_n 3 | _tail_n 1 | cut -d : -f 4 | tr -d "\r\n")"
+    if [ "$__ECC_KEY_LEN" -eq "256" ]; then
+      while [ "${#_ec_r}" -lt "64" ]; do
+        _ec_r="0${_ec_r}"
+      done
+      while [ "${#_ec_s}" -lt "64" ]; do
+        _ec_s="0${_ec_s}"
+      done
+    fi
+    if [ "$__ECC_KEY_LEN" -eq "384" ]; then
+      while [ "${#_ec_r}" -lt "96" ]; do
+        _ec_r="0${_ec_r}"
+      done
+      while [ "${#_ec_s}" -lt "96" ]; do
+        _ec_s="0${_ec_s}"
+      done
+    fi
+    if [ "$__ECC_KEY_LEN" -eq "512" ]; then
+      while [ "${#_ec_r}" -lt "132" ]; do
+        _ec_r="0${_ec_r}"
+      done
+      while [ "${#_ec_s}" -lt "132" ]; do
+        _ec_s="0${_ec_s}"
+      done
+    fi
+    _debug3 "_ec_r" "$_ec_r"
+    _debug3 "_ec_s" "$_ec_s"
+    printf "%s" "$_ec_r$_ec_s" | _h2b | _base64
+  else
+    _err "Unknown key file format."
+    return 1
+  fi
+
+}
+
+#dummy function because proxmox-acme does not call inithttp
+_resethttp() {
+  :
+}
+
 # body  url [needbase64] [POST|PUT|DELETE] [ContentType]
 _post() {
   body="$1"