transfer.sh

SECURITY WARNING

IP filter and HTTP auth bypass via unauthenticated X-Forwarded-For header spoofing

transfer.sh

Easy and fast file sharing from the command-line. This code contains the server with everything you need to create your own instance.

Transfer.sh currently supports the s3 (Amazon S3), gdrive (Google Drive), storj (Storj) providers, and local file system (local).

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Disclaimer

@stefanbenten happens to be a maintainer of this repository and the person who host a well known public installation of the software in the repo.

The two are anyway unrelated, and the repo is not the place to direct requests and issues for any of the pubblic installation.

No third-party public installation of the software in the repo will be advertised or mentioned in the repo itself, for security reasons.

The official position of me, @francescayeye, as maintainer of the repo, is that if you want to use the software you should host your own installation.

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Usage

This section outlines how to use transfer.sh

Upload

$ curl -v --upload-file ./hello.txt https://transfer.sh/hello.txt

Encrypt & Upload

$ gpg --armor --symmetric --output - /tmp/hello.txt | curl --upload-file - https://transfer.sh/test.txt

Download & Decrypt

$ curl https://transfer.sh/1lDau/test.txt | gpg --decrypt --output /tmp/hello.txt

Upload to Virustotal

$ curl -X PUT --upload-file nhgbhhj https://transfer.sh/test.txt/virustotal

Deleting

$ curl -X DELETE <X-Url-Delete Response Header URL>

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Request Headers

This section explains how to handle request headers with curl:

Max-Downloads

$ curl --upload-file ./hello.txt https://transfer.sh/hello.txt -H "Max-Downloads: 1" # Limit the number of downloads

Max-Days

$ curl --upload-file ./hello.txt https://transfer.sh/hello.txt -H "Max-Days: 1" # Set the number of days before deletion

X-Encrypt-Password

Beware, use this feature only on your self-hosted server: trusting a third-party service for server side encryption is at your own risk

$ curl --upload-file ./hello.txt https://your-transfersh-instance.tld/hello.txt -H "X-Encrypt-Password: test" # Encrypt the content server side with AES256 using "test" as password

X-Decrypt-Password

Beware, use this feature only on your self-hosted server: trusting a third-party service for server side encryption is at your own risk

$ curl https://your-transfersh-instance.tld/BAYh0/hello.txt -H "X-Decrypt-Password: test" # Decrypt the content server side with AES256 using "test" as password

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Response Headers

This section explains how to handle response headers:

X-Url-Delete

The URL used to request the deletion of a file and returned as a response header:

curl -sD - --upload-file ./hello.txt https://transfer.sh/hello.txt | grep -i -E 'transfer\.sh|x-url-delete'
x-url-delete: https://transfer.sh/hello.txt/BAYh0/hello.txt/PDw0NHPcqU
https://transfer.sh/hello.txt/BAYh0/hello.txt

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Examples

See good usage examples on examples.md

Link aliases

Create direct download link:

https://transfer.sh/1lDau/test.txt --> https://transfer.sh/get/1lDau/test.txt

Inline file:

https://transfer.sh/1lDau/test.txt --> https://transfer.sh/inline/1lDau/test.txt

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Usage

Parameter	Description	Value	Env
listener	port to use for http (:80)		LISTENER
profile-listener	port to use for profiler (:6060)		PROFILE_LISTENER
force-https	redirect to https	false	FORCE_HTTPS
tls-listener	port to use for https (:443)		TLS_LISTENER
tls-listener-only	flag to enable tls listener only		TLS_LISTENER_ONLY
tls-cert-file	path to tls certificate		TLS_CERT_FILE
tls-private-key	path to tls private key		TLS_PRIVATE_KEY
http-auth-user	user for basic http auth on upload		HTTP_AUTH_USER
http-auth-pass	pass for basic http auth on upload		HTTP_AUTH_PASS
http-auth-htpasswd	htpasswd file path for basic http auth on upload		HTTP_AUTH_HTPASSWD
http-auth-ip-whitelist	comma separated list of allowed ips to upload without auth challenge		HTTP_AUTH_IP_WHITELIST
virustotal-key	VirusTotal API key		VIRUSTOTAL_KEY
ip-whitelist	comma separated list of ips allowed to connect to the service		IP_WHITELIST
ip-blacklist	comma separated list of ips not allowed to connect to the service		IP_BLACKLIST
temp-path	path to temp folder	system temp	TEMP_PATH
web-path	path to static web files (for development or custom front end)		WEB_PATH
proxy-path	path prefix when service is run behind a proxy (a / prefix will be trimmed)		PROXY_PATH
proxy-port	port of the proxy when the service is run behind a proxy		PROXY_PORT
email-contact	email contact for the front end		EMAIL_CONTACT
ga-key	google analytics key for the front end		GA_KEY
provider	which storage provider to use	(s3, storj, gdrive or local)
uservoice-key	user voice key for the front end		USERVOICE_KEY
aws-access-key	aws access key		AWS_ACCESS_KEY
aws-secret-key	aws access key		AWS_SECRET_KEY
bucket	aws bucket		BUCKET
s3-endpoint	Custom S3 endpoint.		S3_ENDPOINT
s3-region	region of the s3 bucket	eu-west-1	S3_REGION
s3-credentials-type	S3 credential mode (legacy or default-sdk-credential-chain)	legacy	S3_CREDENTIALS_TYPE
s3-no-multipart	disables s3 multipart upload	false	S3_NO_MULTIPART
s3-path-style	Forces path style URLs, required for Minio.	false	S3_PATH_STYLE
storj-access	Access for the project		STORJ_ACCESS
storj-bucket	Bucket to use within the project		STORJ_BUCKET
basedir	path storage for local/gdrive provider		BASEDIR
gdrive-client-json-filepath	path to oauth client json config for gdrive provider		GDRIVE_CLIENT_JSON_FILEPATH
gdrive-local-config-path	path to store local transfer.sh config cache for gdrive provider		GDRIVE_LOCAL_CONFIG_PATH
gdrive-chunk-size	chunk size for gdrive upload in megabytes, must be lower than available memory (8 MB)		GDRIVE_CHUNK_SIZE
lets-encrypt-hosts	hosts to use for lets encrypt certificates (comma separated)		HOSTS
log	path to log file		LOG
cors-domains	comma separated list of domains for CORS, setting it enable CORS		CORS_DOMAINS
clamav-host	host for clamav feature		CLAMAV_HOST
perform-clamav-prescan	prescan every upload using clamav (clamav-host must be local clamd unix socket)		PERFORM_CLAMAV_PRESCAN
rate-limit	request per minute		RATE_LIMIT
max-upload-size	max upload size in kilobytes		MAX_UPLOAD_SIZE
purge-days	number of days after the uploads are purged automatically		PURGE_DAYS
purge-interval	interval (hours) to run automatic purge for (excluding S3 and Storj)		PURGE_INTERVAL
random-token-length	length of random token for upload path (double the size for delete path)	6	RANDOM_TOKEN_LENGTH

If you want to use TLS using lets encrypt certificates, set lets-encrypt-hosts to your domain, set tls-listener to :443 and enable force-https.

If you want to use TLS using your own certificates, set tls-listener to :443, force-https, tls-cert-file and tls-private-key.

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Development

Switched to GO111MODULE

go run main.go --provider=local --listener :8080 --temp-path=/tmp/ --basedir=/tmp/

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Build

$ git clone [email protected]:dutchcoders/transfer.sh.git
$ cd transfer.sh
$ go build -o transfersh main.go

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Docker

For easy deployment, we've created an official Docker container. There are two variants, differing only by which user runs the process.

The default one will run as root:

[!WARNING] It is discouraged to use latest tag for WatchTower or similar tools. The latest tag can reference unreleased developer, test builds, and patch releases for older versions. Use an actual version tag until transfer.sh supports major or minor version tags.

docker run --publish 8080:8080 dutchcoders/transfer.sh:latest --provider local --basedir /tmp/

No root

The -noroot tags indicate image builds that run with least privilege to reduce the attack surface might an application get compromised.

[!NOTE] Using -noroot is recommended

The one tagged with the suffix -noroot will use 5000 as both UID and GID:

docker run --publish 8080:8080 dutchcoders/transfer.sh:latest-noroot --provider local --basedir /tmp/

[!NOTE] Development history details at:

• https://github.com/dutchcoders/transfer.sh/pull/418

Tags

Name	Usage
latest	Latest CI build, can be nightly, at commit, at tag, etc.
latest-noroot	Latest CI build, can be nightly, at commit, at tag, etc. using [no root]
nightly	Scheduled CI build every midnight UTC
nightly-noroot	Scheduled CI build every midnight UTC using [no root]
edge	Latest CI build after every commit on main
edge-noroot	Latest CI build after every commit on main using [no root]
vx.y.z	CI build after tagging a release
vx.y.z-noroot	CI build after tagging a release using [no root]

Building the Container

You can also build the container yourself. This allows you to choose which UID/GID will be used, e.g. when using NFS mounts:

# Build arguments:
# * RUNAS: If empty, the container will run as root.
#          Set this to anything to enable UID/GID selection.
# * PUID:  UID of the process. Needs RUNAS != "". Defaults to 5000.
# * PGID:  GID of the process. Needs RUNAS != "". Defaults to 5000.

docker build -t transfer.sh-noroot --build-arg RUNAS=doesntmatter --build-arg PUID=1337 --build-arg PGID=1338 .

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S3 Usage

For the usage with a AWS S3 Bucket, you just need to specify the following options:

• provider --provider s3
• aws-access-key (either via flag or environment variable AWS_ACCESS_KEY)
• aws-secret-key (either via flag or environment variable AWS_SECRET_KEY)
• bucket (either via flag or environment variable BUCKET)
• s3-region (either via flag or environment variable S3_REGION)

The legacy credential type is the default and requires both static credential options. To use the AWS SDK default credential chain, explicitly set --s3-credentials-type default-sdk-credential-chain (or S3_CREDENTIALS_TYPE=default-sdk-credential-chain). The SDK chain supports environment credentials, shared AWS configuration files, ECS task roles, EC2 instance profiles, and EKS IRSA.

If you specify the s3-region, you don't need to set the endpoint URL since the correct endpoint will used automatically.

Custom S3 providers

To use a custom non-AWS S3 provider, you need to specify the endpoint as defined from your cloud provider.

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Storj Network Provider

To use the Storj Network as a storage provider you need to specify the following flags:

• provider --provider storj
• storj-access (either via flag or environment variable STORJ_ACCESS)
• storj-bucket (either via flag or environment variable STORJ_BUCKET)

Creating Bucket and Scope

You need to create an access grant (or copy it from the uplink configuration) and a bucket in preparation.

To get started, log in to your account and go to the Access Grant Menu and start the Wizard on the upper right.

Enter your access grant name of choice, hit Next and restrict it as necessary/preferred. Afterwards continue either in CLI or within the Browser. Next, you'll be asked for a Passphrase used as Encryption Key. Make sure to save it in a safe place. Without it, you will lose the ability to decrypt your files!

Afterwards, you can copy the access grant and then start the startup of the transfer.sh endpoint. It is recommended to provide both the access grant and the bucket name as ENV Variables for enhanced security.

Example:

export STORJ_BUCKET=<BUCKET NAME>
export STORJ_ACCESS=<ACCESS GRANT>
transfer.sh --provider storj

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Google Drive Usage

For the usage with Google drive, you need to specify the following options:

• provider
• gdrive-client-json-filepath
• gdrive-local-config-path
• basedir

Creating Gdrive Client Json

You need to create an OAuth Client id from console.cloud.google.com, download the file, and place it into a safe directory.

Usage example

go run main.go --provider gdrive --basedir /tmp/ --gdrive-client-json-filepath /[credential_dir] --gdrive-local-config-path [directory_to_save_config]

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Shell functions

Bash, ash and zsh (multiple files uploaded as zip archive)

Add this to .bashrc or .zshrc or its equivalent

transfer() (if [ $# -eq 0 ]; then printf "No arguments specified.\nUsage:\n transfer <file|directory>\n ... | transfer <file_name>\n">&2; return 1; fi; file_name=$(basename "$1"); if [ -t 0 ]; then file="$1"; if [ ! -e "$file" ]; then echo "$file: No such file or directory">&2; return 1; fi; if [ -d "$file" ]; then cd "$file" || return 1; file_name="$file_name.zip"; set -- zip -r -q - .; else set -- cat "$file"; fi; else set -- cat; fi; url=$("$@" | curl --silent --show-error --progress-bar --upload-file "-" "https://transfer.sh/$file_name"); echo "$url"; )

Now you can use transfer function

$ transfer hello.txt

Bash and zsh (with delete url, delete token output and prompt before uploading)

Add this to .bashrc or .zshrc or its equivalent

transfer()
{
    local file
    declare -a file_array
    file_array=("${@}")

    if [[ "${file_array[@]}" == "" || "${1}" == "--help" || "${1}" == "-h" ]]
    then
        echo "${0} - Upload arbitrary files to \"transfer.sh\"."
        echo ""
        echo "Usage: ${0} [options] [<file>]..."
        echo ""
        echo "OPTIONS:"
        echo "  -h, --help"
        echo "      show this message"
        echo ""
        echo "EXAMPLES:"
        echo "  Upload a single file from the current working directory:"
        echo "      ${0} \"image.img\""
        echo ""
        echo "  Upload multiple files from the current working directory:"
        echo "      ${0} \"image.img\" \"image2.img\""
        echo ""
        echo "  Upload a file from a different directory:"
        echo "      ${0} \"/tmp/some_file\""
        echo ""
        echo "  Upload all files from the current working directory. Be aware of the webserver's rate limiting!:"
        echo "      ${0} *"
        echo ""
        echo "  Upload a single file from the current working directory and filter out the delete token and download link:"
        echo "      ${0} \"image.img\" | awk --field-separator=\": \" '/Delete token:/ { print \$2 } /Download link:/ { print \$2 }'"
        echo ""
        echo "  Show help text from \"transfer.sh\":"
        echo "      curl --request GET \"https://transfer.sh\""
        return 0
    else
        for file in "${file_array[@]}"
        do
            if [[ ! -f "${file}" ]]
            then
                echo -e "\e[01;31m'${file}' could not be found or is not a file.\e[0m" >&2
                return 1
            fi
        done
        unset file
    fi

    local upload_files
    local curl_output
    local awk_output

    du -c -k -L "${file_array[@]}" >&2
    # be compatible with "bash"
    if [[ "${ZSH_NAME}" == "zsh" ]]
    then
        read $'upload_files?\e[01;31mDo you really want to upload the above files ('"${#file_array[@]}"$') to "transfer.sh"? (Y/n): \e[0m'
    elif [[ "${BASH}" == *"bash"* ]]
    then
        read -p $'\e[01;31mDo you really want to upload the above files ('"${#file_array[@]}"$') to "transfer.sh"? (Y/n): \e[0m' upload_files
    fi

    case "${upload_files:-y}" in
        "y"|"Y")
            # for the sake of the progress bar, execute "curl" for each file.
            # the parameters "--include" and "--form" will suppress the progress bar.
            for file in "${file_array[@]}"
            do
                # show delete link and filter out the delete token from the response header after upload.
                # it is important to save "curl's" "stdout" via a subshell to a variable or redirect it to another command,
                # which just redirects to "stdout" in order to have a sane output afterwards.
                # the progress bar is redirected to "stderr" and is only displayed,
                # if "stdout" is redirected to something; e.g. ">/dev/null", "tee /dev/null" or "| <some_command>".
                # the response header is redirected to "stdout", so redirecting "stdout" to "/dev/null" does not make any sense.
                # redirecting "curl's" "stderr" to "stdout" ("2>&1") will suppress the progress bar.
                curl_output=$(curl --request PUT --progress-bar --dump-header - --upload-file "${file}" "https://transfer.sh/")
                awk_output=$(awk \
                    'gsub("\r", "", $0) && tolower($1) ~ /x-url-delete/ \
                    {
                        delete_link=$2;
                        print "Delete command: curl --request DELETE " "\""delete_link"\"";

                        gsub(".*/", "", delete_link);
                        delete_token=delete_link;
                        print "Delete token: " delete_token;
                    }

                    END{
                        print "Download link: " $0;
                    }' <<< "${curl_output}")

                # return the results via "stdout", "awk" does not do this for some reason.
                echo -e "${awk_output}\n"

                # avoid rate limiting as much as possible; nginx: too many requests.
                if (( ${#file_array[@]} > 4 ))
                then
                    sleep 5
                fi
            done
            ;;

        "n"|"N")
            return 1
            ;;

        *)
            echo -e "\e[01;31mWrong input: '${upload_files}'.\e[0m" >&2
            return 1
    esac
}

Sample output

$ ls -lh
total 20M
-rw-r--r-- 1 <some_username> <some_username> 10M Apr  4 21:08 image.img
-rw-r--r-- 1 <some_username> <some_username> 10M Apr  4 21:08 image2.img
$ transfer image*
10240K  image2.img
10240K  image.img
20480K  total
Do you really want to upload the above files (2) to "transfer.sh"? (Y/n):
######################################################################################################################################################################################################################################## 100.0%
Delete command: curl --request DELETE "https://transfer.sh/wJw9pz/image2.img/mSctGx7pYCId"
Delete token: mSctGx7pYCId
Download link: https://transfer.sh/wJw9pz/image2.img

######################################################################################################################################################################################################################################## 100.0%
Delete command: curl --request DELETE "https://transfer.sh/ljJc5I/image.img/nw7qaoiKUwCU"
Delete token: nw7qaoiKUwCU
Download link: https://transfer.sh/ljJc5I/image.img

$ transfer "image.img" | awk --field-separator=": " '/Delete token:/ { print $2 } /Download link:/ { print $2 }'
10240K  image.img
10240K  total
Do you really want to upload the above files (1) to "transfer.sh"? (Y/n):
######################################################################################################################################################################################################################################## 100.0%
tauN5dE3fWJe
https://transfer.sh/MYkuqn/image.img

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Contributions

Contributions are welcome.

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Creators

Remco Verhoef

• https://twitter.com/remco_verhoef
• https://twitter.com/dutchcoders

Uvis Grinfelds

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Maintainers

• Francesca Schicchera
• Stefan Benten

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Copyright and License

Code and documentation copyright 2011-2018 Remco Verhoef. Code and documentation copyright 2018-2020 Andrea Spacca. Code and documentation copyright 2020- Andrea Spacca and Stefan Benten.

Code released under the MIT license.