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Incorrect retry actions after transfer connection drops because server reports too long file size

See original GitHub issue

FTP Server OS: Apache FtpServer

Client Computer OS: Ubuntu (amazon linux 2)

FluentFTP Version: 42.0

Framework: .NET 6

It is working very few time under Ubuntu, but under Windows I got a file with double or 3x size.

Logs :


# AutoConnect()

# AutoDetect(True, False)

# ConnectAsync()
Status:   FluentFTP 42.0.0.0
Status:   Connecting to *.*.*.*:21
Status:   Waiting for a response
Response: 220 Service ready for new user.
Command:  AUTH TLS
Status:   Waiting for response to: AUTH TLS
Response: 431 Service is unavailable.
Command:  USER ****
Status:   Waiting for response to: USER ****
Response: 331 User name okay, need password for ****.
Command:  PASS ***
Status:   Waiting for response to: PASS ***
Response: 230 User logged in, proceed.
Command:  FEAT
Status:   Waiting for response to: FEAT
Response: 211-Extensions supported
Response: SIZE
Response: MDTM
Response: REST STREAM
Response: LANG en;zh-tw;ja;is
Response: MLST Size;Modify;Type;Perm
Response: AUTH SSL
Response: AUTH TLS
Response: MODE Z
Response: UTF8
Response: TVFS
Response: MD5
Response: MMD5
Response: MFMT
Response: 211 End
Status:   Text encoding: System.Text.UTF8Encoding+UTF8EncodingSealed
Command:  OPTS UTF8 ON
Status:   Waiting for response to: OPTS UTF8 ON
Response: 200 Command OPTS okay.
Command:  SYST
Status:   Waiting for response to: SYST
Response: 215 UNIX Type: Apache FtpServer
Status:   Listing parser set to: Machine

# GetFileSize("****.txt.gz", -1)
Command:  SIZE ****.txt.gz
Status:   Waiting for response to: SIZE ****.txt.gz
Response: 213 85049263

# GetModifiedTime("****.txt.gz")
Command:  MDTM ****.txt.gz
Status:   Waiting for response to: MDTM ****.txt.gz
Response: 213 20221115094042.667
Downloading file to:

# DownloadFile("/tmp/tmp9CCdaq.tmp", "****.txt.gz", Resume, Retry)

# GetFileSize("****.txt.gz", -1)
Command:  SIZE ****.txt.gz
Status:   Waiting for response to: SIZE ****.txt.gz
Response: 213 85049263

# OpenRead("****.txt.gz", Binary, 0, 85049263)
Command:  TYPE I
Status:   Waiting for response to: TYPE I
Response: 200 Command TYPE okay.

# OpenPassiveDataStreamAsync(PASV, "RETR ****.txt.gz", 0)
Command:  PASV
Status:   Waiting for response to: PASV
Response: 227 Entering Passive Mode (*,*,*,*,181,29)
Status:   Connecting to *.*.*.*:46365
Command:  RETR ****.txt.gz
Status:   Waiting for response to: RETR ****.txt.gz
Response: 150 Getting data connection.

Status:   Disposing FtpSocketStream...

# OpenRead("****.txt.gz", Binary, 74993893, 0)

# GetFileSize("****.txt.gz", -1)
Status:   Socket has stale data - prior to command execution
Status:   The stale data was:
Stale:    226 Transfer complete.
Status:   Closing stream because of stale data
Status:   Disposing FtpSocketStream...

# ConnectAsync()
Status:   FluentFTP 42.0.0.0
Status:   Connecting to *.*.*.*:21
Status:   Waiting for a response
Response: 220 Service ready for new user.
Command:  USER ****
Status:   Waiting for response to: USER ****
Response: 331 User name okay, need password for ****.
Command:  PASS ***
Status:   Waiting for response to: PASS ***
Response: 230 User logged in, proceed.
Command:  FEAT
Status:   Waiting for response to: FEAT
Response: 211-Extensions supported
Response: SIZE
Response: MDTM
Response: REST STREAM
Response: LANG en;zh-tw;ja;is
Response: MLST Size;Modify;Type;Perm
Response: AUTH SSL
Response: AUTH TLS
Response: MODE Z
Response: UTF8
Response: TVFS
Response: MD5
Response: MMD5
Response: MFMT
Response: 211 End
Status:   Text encoding: System.Text.UTF8Encoding+UTF8EncodingSealed
Command:  OPTS UTF8 ON
Status:   Waiting for response to: OPTS UTF8 ON
Response: 200 Command OPTS okay.
Command:  SYST
Status:   Waiting for response to: SYST
Response: 215 UNIX Type: Apache FtpServer
Status:   Listing parser set to: Machine
Command:  SIZE ****.txt.gz
Status:   Waiting for response to: SIZE ****.txt.gz
Response: 213 85049263
Command:  TYPE I
Status:   Waiting for response to: TYPE I
Response: 200 Command TYPE okay.

# OpenPassiveDataStreamAsync(PASV, "RETR ****.txt.gz", 74993893)
Command:  PASV
Status:   Waiting for response to: PASV
Response: 227 Entering Passive Mode (*,*,*,*,181,11)
Status:   Connecting to *.*.*.*:46347
Command:  REST 74993893
Status:   Waiting for response to: REST 74993893
Response: 350 Restarting at 74993893. Send STORE or RETRIEVE to initiate transfer.
Command:  RETR ****.txt.gz
Status:   Waiting for response to: RETR ****.txt.gz
Response: 150 Getting data connection.

Status:   Disposing FtpSocketStream...

# OpenRead("****.txt.gz", Binary, 149987786, 0)

# GetFileSize("****.txt.gz", -1)
Command:  SIZE ****.txt.gz
Status:   Waiting for response to: SIZE ****.txt.gz
Response: 226 Transfer complete.

# OpenPassiveDataStreamAsync(PASV, "RETR ****.txt.gz", 149987786)
Command:  PASV
Status:   Waiting for response to: PASV
Response: 213 85049263
Status:   Disposing FtpSocketStream...

# Dispose()
Status:   Disposing FtpClient object...
Status:   Disposing FtpSocketStream...
Unhandled exception. FluentFTP.FtpException: Error while downloading the file from the server. See InnerException for more info.
 ---> FluentFTP.FtpException: Malformed PASV response: 85049263
   at FluentFTP.Client.BaseClient.BaseFtpClient.GetPassivePort(FtpDataConnectionType type, FtpReply reply, String& host, Int32& port)
   at FluentFTP.AsyncFtpClient.OpenPassiveDataStreamAsync(FtpDataConnectionType type, String command, Int64 restart, CancellationToken token)
   at FluentFTP.AsyncFtpClient.OpenDataStreamAsync(String command, Int64 restart, CancellationToken token)
   at FluentFTP.AsyncFtpClient.OpenRead(String path, FtpDataType type, Int64 restart, Int64 fileLen, CancellationToken token)
   at FluentFTP.AsyncFtpClient.ResumeDownloadAsync(String remotePath, Stream downStream, Int64 offset, IOException ex, CancellationToken token)
   at FluentFTP.AsyncFtpClient.DownloadFileInternalAsync(String localPath, String remotePath, Stream outStream, Int64 restartPosition, IProgress`1 progress, CancellationToken token, FtpProgress metaProgress, Int64 knownFileSize, Boolean isAppend)
   --- End of inner exception stack trace ---
   at FluentFTP.AsyncFtpClient.DownloadFileInternalAsync(String localPath, String remotePath, Stream outStream, Int64 restartPosition, IProgress`1 progress, CancellationToken token, FtpProgress metaProgress, Int64 knownFileSize, Boolean isAppend)
   at FluentFTP.AsyncFtpClient.DownloadFileToFileAsync(String localPath, String remotePath, FtpLocalExists existsMode, FtpVerify verifyOptions, IProgress`1 progress, CancellationToken token, FtpProgress metaProgress)
   at FluentFTP.AsyncFtpClient.DownloadFile(String localPath, String remotePath, FtpLocalExists existsMode, FtpVerify verifyOptions, IProgress`1 progress, CancellationToken token)