[pbs-devel] [PATCH v5 proxmox-backup 3/4] add file inspection to pb-debug

[Hannes Laimer <h.laimer@proxmox.com>]

Adds possibility to inspect .blob, .fidx and .didx files. For index
files a list of the chunks referenced will be printed in addition to
some other inforation. .blob files can be decoded into file or directly
into stdout. Options:
 - file: path to the file
 - [opt] decode: path to a file or stdout(-), if specidied, the file will be
   decoded into the specified location [only for blob files, no effect
  with index files]
 - [opt] keyfile: path to a keyfile, needed if decode is specified and the
   data was encrypted

Signed-off-by: Hannes Laimer <h.laimer@proxmox.com>
---
v5:
 - combine path for fixed and dynamic index fliles to avoid duplicate
   code

v4:
 - only the types of file that are passed by the user are check with the
   magic number, when looking for index files just the filename ending
   is checked -> don't have to open the file for that
 - not sure if a function for the magic nr reading, seek reset makes
   sense(?), it's just two lines
 
 src/bin/proxmox_backup_debug/inspect.rs | 119 ++++++++++++++++++++++--
 1 file changed, 112 insertions(+), 7 deletions(-)

diff --git a/src/bin/proxmox_backup_debug/inspect.rs b/src/bin/proxmox_backup_debug/inspect.rs
index dd6ee287..2d95448e 100644
--- a/src/bin/proxmox_backup_debug/inspect.rs
+++ b/src/bin/proxmox_backup_debug/inspect.rs
@@ -1,19 +1,26 @@
+use std::collections::HashSet;
+use std::fs::File;
+use std::io::{Read, Seek, SeekFrom};
 use std::path::Path;
 
 use anyhow::{format_err, Error};
-use proxmox::api::cli::{
-    format_and_print_result, get_output_format, CliCommand, CliCommandMap, CommandLineInterface,
-};
-use proxmox::api::{api, cli::*};
 use serde_json::{json, Value};
 use walkdir::WalkDir;
 
+use crate::{get_encryption_key_password, KEYFILE_SCHEMA, PATH_SCHEMA};
+use proxmox::api::{
+    api,
+    cli::{
+        format_and_print_result, get_output_format, CliCommand, CliCommandMap,
+        CommandLineInterface, OUTPUT_FORMAT,
+    },
+};
 use proxmox_backup::backup::{
     load_and_decrypt_key, CryptConfig, DataBlob, DynamicIndexReader, FixedIndexReader, IndexFile,
+    COMPRESSED_BLOB_MAGIC_1_0, DYNAMIC_SIZED_CHUNK_INDEX_1_0, ENCRYPTED_BLOB_MAGIC_1_0,
+    ENCR_COMPR_BLOB_MAGIC_1_0, FIXED_SIZED_CHUNK_INDEX_1_0, UNCOMPRESSED_BLOB_MAGIC_1_0,
 };
 
-use crate::{get_encryption_key_password, KEYFILE_SCHEMA, PATH_SCHEMA};
-
 use proxmox_backup::tools::outfile_or_stdout;
 
 /// Decodes a blob and writes its content either to stdout or into a file
@@ -37,6 +44,102 @@ fn decode_blob(
     Ok(())
 }
 
+#[api(
+    input: {
+        properties: {
+            file: {
+                schema: PATH_SCHEMA,
+            },
+            "decode": {
+                schema: PATH_SCHEMA,
+                optional: true,
+            },
+            "keyfile": {
+                schema: KEYFILE_SCHEMA,
+                optional: true,
+            },
+            "output-format": {
+                schema: OUTPUT_FORMAT,
+                optional: true,
+            },
+        }
+    }
+)]
+/// Inspect a file
+fn inspect_file(
+    file: String,
+    decode: Option<String>,
+    keyfile: Option<String>,
+    param: Value,
+) -> Result<(), Error> {
+    let output_format = get_output_format(&param);
+
+    let mut file = File::open(Path::new(&file))?;
+    let mut magic = [0; 8];
+    file.read_exact(&mut magic)?;
+    file.seek(SeekFrom::Start(0))?;
+    let val = match magic {
+        UNCOMPRESSED_BLOB_MAGIC_1_0
+        | COMPRESSED_BLOB_MAGIC_1_0
+        | ENCRYPTED_BLOB_MAGIC_1_0
+        | ENCR_COMPR_BLOB_MAGIC_1_0 => {
+            let data_blob = DataBlob::load_from_reader(&mut file)?;
+            let key_file_path = keyfile.as_ref().map(Path::new);
+
+            let (decode_output_path, to_stdout) = (
+                decode.as_ref().map(Path::new),
+                decode.clone().map_or(false, |p| p.eq("-")),
+            );
+
+            if decode_output_path.is_some() || to_stdout {
+                decode_blob(decode_output_path, key_file_path, None, &data_blob)?;
+            }
+
+            let crypt_mode = data_blob.crypt_mode()?;
+            Ok(json!({
+                "encryption": crypt_mode,
+                "raw_size": data_blob.raw_size(),
+            }))
+        }
+        FIXED_SIZED_CHUNK_INDEX_1_0 | DYNAMIC_SIZED_CHUNK_INDEX_1_0 => {
+            let index: Box<dyn IndexFile> = match magic {
+                FIXED_SIZED_CHUNK_INDEX_1_0 => {
+                    Ok(Box::new(FixedIndexReader::new(file)?) as Box<dyn IndexFile>)
+                }
+                DYNAMIC_SIZED_CHUNK_INDEX_1_0 => {
+                    Ok(Box::new(DynamicIndexReader::new(file)?) as Box<dyn IndexFile>)
+                }
+                _ => Err(format_err!("This is technically not possible")),
+            }?;
+
+            let mut ctime_str = index.index_ctime().to_string();
+            if let Ok(s) = proxmox::tools::time::strftime_local("%c", index.index_ctime()) {
+                ctime_str = s;
+            }
+
+            let mut chunk_digests = HashSet::new();
+
+            for pos in 0..index.index_count() {
+                let digest = index.index_digest(pos).unwrap();
+                chunk_digests.insert(proxmox::tools::digest_to_hex(digest));
+            }
+
+            Ok(json!({
+                "size": index.index_size(),
+                "ctime": ctime_str,
+                "chunk-digests": chunk_digests
+            }))
+        }
+        _ => Err(format_err!(
+            "Only .blob, .fidx and .didx files may be inspected"
+        )),
+    }?;
+
+    format_and_print_result(&val, &output_format);
+
+    Ok(())
+}
+
 #[api(
     input: {
         properties: {
@@ -156,7 +259,9 @@ fn inspect_chunk(
 }
 
 pub fn inspect_commands() -> CommandLineInterface {
-    let cmd_def = CliCommandMap::new().insert("chunk", CliCommand::new(&API_METHOD_INSPECT_CHUNK));
+    let cmd_def = CliCommandMap::new()
+        .insert("file", CliCommand::new(&API_METHOD_INSPECT_FILE))
+        .insert("chunk", CliCommand::new(&API_METHOD_INSPECT_CHUNK));
 
     cmd_def.into()
 }
-- 
2.20.1