diff --git a/src/api2/backup.rs b/src/api2/backup.rs
index 1f53d2c9..0d580b44 100644
--- a/src/api2/backup.rs
+++ b/src/api2/backup.rs
@@ -323,7 +323,7 @@ fn dynamic_append (
 
     for (i, item) in digest_list.iter().enumerate() {
         let digest_str = item.as_str().unwrap();
-        let digest = crate::tools::hex_to_digest(digest_str)?;
+        let digest = proxmox::tools::hex_to_digest(digest_str)?;
         let offset = offset_list[i].as_u64().unwrap();
         let size = env.lookup_chunk(&digest).ok_or_else(|| format_err!("no such chunk {}", digest_str))?;
 
@@ -375,7 +375,7 @@ fn fixed_append (
 
     for (i, item) in digest_list.iter().enumerate() {
         let digest_str = item.as_str().unwrap();
-        let digest = crate::tools::hex_to_digest(digest_str)?;
+        let digest = proxmox::tools::hex_to_digest(digest_str)?;
         let offset = offset_list[i].as_u64().unwrap();
         let size = env.lookup_chunk(&digest).ok_or_else(|| format_err!("no such chunk {}", digest_str))?;
 
diff --git a/src/api2/backup/environment.rs b/src/api2/backup/environment.rs
index ade2ac98..6131b632 100644
--- a/src/api2/backup/environment.rs
+++ b/src/api2/backup/environment.rs
@@ -4,7 +4,7 @@ use std::collections::HashMap;
 
 use serde_json::Value;
 
-use crate::tools;
+use proxmox::tools;
 
 use crate::api_schema::router::{RpcEnvironment, RpcEnvironmentType};
 use crate::server::WorkerTask;
diff --git a/src/api2/backup/upload_chunk.rs b/src/api2/backup/upload_chunk.rs
index 3ed54c9c..cd9bc55b 100644
--- a/src/api2/backup/upload_chunk.rs
+++ b/src/api2/backup/upload_chunk.rs
@@ -102,7 +102,7 @@ fn upload_fixed_chunk(
     let encoded_size = tools::required_integer_param(&param, "encoded-size")? as u32;
 
     let digest_str = tools::required_string_param(&param, "digest")?;
-    let digest = crate::tools::hex_to_digest(digest_str)?;
+    let digest = proxmox::tools::hex_to_digest(digest_str)?;
 
     let env: &BackupEnvironment = rpcenv.as_ref();
 
@@ -114,7 +114,7 @@ fn upload_fixed_chunk(
 
              let result = result.and_then(|(digest, size, compressed_size, is_duplicate)| {
                  env.register_fixed_chunk(wid, digest, size, compressed_size, is_duplicate)?;
-                 let digest_str = tools::digest_to_hex(&digest);
+                 let digest_str = proxmox::tools::digest_to_hex(&digest);
                  env.debug(format!("upload_chunk done: {} bytes, {}", size, digest_str));
                  Ok(json!(digest_str))
              });
@@ -158,7 +158,7 @@ fn upload_dynamic_chunk(
     let encoded_size = tools::required_integer_param(&param, "encoded-size")? as u32;
 
     let digest_str = tools::required_string_param(&param, "digest")?;
-    let digest = crate::tools::hex_to_digest(digest_str)?;
+    let digest = proxmox::tools::hex_to_digest(digest_str)?;
 
     let env: &BackupEnvironment = rpcenv.as_ref();
 
@@ -170,7 +170,7 @@ fn upload_dynamic_chunk(
 
              let result = result.and_then(|(digest, size, compressed_size, is_duplicate)| {
                  env.register_dynamic_chunk(wid, digest, size, compressed_size, is_duplicate)?;
-                 let digest_str = tools::digest_to_hex(&digest);
+                 let digest_str = proxmox::tools::digest_to_hex(&digest);
                  env.debug(format!("upload_chunk done: {} bytes, {}", size, digest_str));
                  Ok(json!(digest_str))
              });
diff --git a/src/api2/node/dns.rs b/src/api2/node/dns.rs
index f78d5179..8f83ecb6 100644
--- a/src/api2/node/dns.rs
+++ b/src/api2/node/dns.rs
@@ -25,7 +25,7 @@ fn read_etc_resolv_conf() -> Result<Value, Error> {
 
     let raw = tools::file_get_contents(RESOLV_CONF_FN)?;
 
-    result["digest"] = Value::from(tools::digest_to_hex(&sha::sha256(&raw)));
+    result["digest"] = Value::from(proxmox::tools::digest_to_hex(&sha::sha256(&raw)));
 
     let data = String::from_utf8(raw)?;
 
@@ -66,7 +66,7 @@ fn update_dns(
     let search = tools::required_string_param(&param, "search")?;
 
     let raw = tools::file_get_contents(RESOLV_CONF_FN)?;
-    let old_digest = tools::digest_to_hex(&sha::sha256(&raw));
+    let old_digest = proxmox::tools::digest_to_hex(&sha::sha256(&raw));
 
     if let Some(digest) = param["digest"].as_str() {
         tools::assert_if_modified(&old_digest, &digest)?;
diff --git a/src/backup/chunk_store.rs b/src/backup/chunk_store.rs
index c5b18d1d..f76d6543 100644
--- a/src/backup/chunk_store.rs
+++ b/src/backup/chunk_store.rs
@@ -148,7 +148,7 @@ impl ChunkStore {
         let mut chunk_path = self.chunk_dir.clone();
         let prefix = digest_to_prefix(&digest);
         chunk_path.push(&prefix);
-        let digest_str = tools::digest_to_hex(&digest);
+        let digest_str = proxmox::tools::digest_to_hex(&digest);
         chunk_path.push(&digest_str);
 
         const UTIME_NOW: i64 = ((1 << 30) - 1);
@@ -177,7 +177,7 @@ impl ChunkStore {
         let mut chunk_path = self.chunk_dir.clone();
         let prefix = digest_to_prefix(digest);
         chunk_path.push(&prefix);
-        let digest_str = tools::digest_to_hex(digest);
+        let digest_str = proxmox::tools::digest_to_hex(digest);
         chunk_path.push(&digest_str);
 
         let mut file = std::fs::File::open(&chunk_path)
@@ -324,12 +324,12 @@ impl ChunkStore {
 
         let digest = chunk.digest();
 
-        //println!("DIGEST {}", tools::digest_to_hex(digest));
+        //println!("DIGEST {}", proxmox::tools::digest_to_hex(digest));
 
         let mut chunk_path = self.chunk_dir.clone();
         let prefix = digest_to_prefix(digest);
         chunk_path.push(&prefix);
-        let digest_str = tools::digest_to_hex(digest);
+        let digest_str = proxmox::tools::digest_to_hex(digest);
         chunk_path.push(&digest_str);
 
         let lock = self.mutex.lock();
diff --git a/src/backup/dynamic_index.rs b/src/backup/dynamic_index.rs
index d2ac9064..1af99776 100644
--- a/src/backup/dynamic_index.rs
+++ b/src/backup/dynamic_index.rs
@@ -182,7 +182,7 @@ impl DynamicIndexReader {
             let digest = self.chunk_digest(pos);
             if let Err(err) = self.store.touch_chunk(digest) {
                 bail!("unable to access chunk {}, required by {:?} - {}",
-                      tools::digest_to_hex(digest), self.filename, err);
+                      proxmox::tools::digest_to_hex(digest), self.filename, err);
             }
         }
         Ok(())
@@ -589,7 +589,7 @@ impl DynamicChunkWriter {
                 }
 
                 println!("ADD CHUNK {:016x} {} {}% {} {}", self.chunk_offset, chunk_size,
-                         (compressed_size*100)/(chunk_size as u64), is_duplicate,  tools::digest_to_hex(digest));
+                         (compressed_size*100)/(chunk_size as u64), is_duplicate, proxmox::tools::digest_to_hex(digest));
                 self.index.add_chunk(self.chunk_offset as u64, &digest)?;
                 self.chunk_buffer.truncate(0);
                 return Ok(());
diff --git a/src/backup/fixed_index.rs b/src/backup/fixed_index.rs
index 40d727df..c1f3330d 100644
--- a/src/backup/fixed_index.rs
+++ b/src/backup/fixed_index.rs
@@ -158,7 +158,7 @@ impl FixedIndexReader {
             let digest = self.index_digest(pos).unwrap();
             if let Err(err) = self.store.touch_chunk(digest) {
                 bail!("unable to access chunk {}, required by {:?} - {}",
-                      tools::digest_to_hex(digest), self.filename, err);
+                      proxmox::tools::digest_to_hex(digest), self.filename, err);
             }
         }
 
@@ -361,7 +361,7 @@ impl FixedIndexWriter {
         let digest = chunk_info.chunk.digest();
 
         println!("ADD CHUNK {} {} {}% {} {}", pos, chunk_len,
-                 (compressed_size*100)/(chunk_len as u64), is_duplicate, tools::digest_to_hex(digest));
+                 (compressed_size*100)/(chunk_len as u64), is_duplicate, proxmox::tools::digest_to_hex(digest));
 
         if is_duplicate {
             stat.duplicate_chunks += 1;
diff --git a/src/client/http_client.rs b/src/client/http_client.rs
index 329536d4..c366ceef 100644
--- a/src/client/http_client.rs
+++ b/src/client/http_client.rs
@@ -589,8 +589,8 @@ impl BackupClient {
                             let mut digest_list = vec![];
                             let mut offset_list = vec![];
                             for (offset, digest) in chunk_list {
-                                //println!("append chunk {} (offset {})", tools::digest_to_hex(&digest), offset);
-                                digest_list.push(tools::digest_to_hex(&digest));
+                                //println!("append chunk {} (offset {})", proxmox::tools::digest_to_hex(&digest), offset);
+                                digest_list.push(proxmox::tools::digest_to_hex(&digest));
                                 offset_list.push(offset);
                             }
                             println!("append chunks list len ({})", digest_list.len());
@@ -651,7 +651,7 @@ impl BackupClient {
                         DigestListDecoder::new(body.map_err(Error::from))
                             .for_each(move |chunk| {
                                 let _ = release_capacity.release_capacity(chunk.len());
-                                println!("GOT DOWNLOAD {}", tools::digest_to_hex(&chunk));
+                                println!("GOT DOWNLOAD {}", proxmox::tools::digest_to_hex(&chunk));
                                 known_chunks.lock().unwrap().insert(chunk);
                                 Ok(())
                             })
@@ -713,7 +713,7 @@ impl BackupClient {
                 if let MergedChunkInfo::New(chunk_info) = merged_chunk_info {
                     let offset = chunk_info.offset;
                     let digest = *chunk_info.chunk.digest();
-                    let digest_str = tools::digest_to_hex(&digest);
+                    let digest_str = proxmox::tools::digest_to_hex(&digest);
                     let upload_queue = upload_queue.clone();
 
                     println!("upload new chunk {} ({} bytes, offset {})", digest_str,
diff --git a/src/tools.rs b/src/tools.rs
index 78a01625..011ca19c 100644
--- a/src/tools.rs
+++ b/src/tools.rs
@@ -567,46 +567,6 @@ pub fn get_hardware_address() -> Result<String, Error> {
     Ok(format!("{:0x}", digest))
 }
 
-const HEX_CHARS: &'static [u8; 16] = b"0123456789abcdef";
-
-pub fn digest_to_hex(digest: &[u8]) -> String {
-    let mut buf = Vec::<u8>::with_capacity(digest.len()*2);
-
-    for i in 0..digest.len() {
-        buf.push(HEX_CHARS[(digest[i] >> 4) as usize]);
-        buf.push(HEX_CHARS[(digest[i] & 0xf) as usize]);
-    }
-
-    unsafe { String::from_utf8_unchecked(buf) }
-}
-
-pub fn hex_to_digest(hex: &str) -> Result<[u8; 32], Error> {
-    let mut digest = [0u8; 32];
-
-    let bytes = hex.as_bytes();
-
-    if bytes.len() != 64 { bail!("got wrong digest length."); }
-
-    let val = |c| {
-        if c >= b'0' && c <= b'9' { return Ok(c - b'0'); }
-        if c >= b'a' && c <= b'f' { return Ok(c - b'a' + 10); }
-        if c >= b'A' && c <= b'F' { return Ok(c - b'A' + 10); }
-        bail!("found illegal hex character.");
-    };
-
-    let mut pos = 0;
-    for pair in bytes.chunks(2) {
-        if pos >= digest.len() { bail!("hex digest too long."); }
-        let h = val(pair[0])?;
-        let l = val(pair[1])?;
-        digest[pos] = (h<<4)|l;
-        pos +=1;
-    }
-
-    if pos != digest.len() {  bail!("hex digest too short."); }
-
-    Ok(digest)
-}
 
 pub fn assert_if_modified(digest1: &str, digest2: &str) -> Result<(), Error> {
     if digest1 != digest2 {