/usr/share/plowshare/modules/filebin_ca.sh is in plowshare-modules 0~git20171112.e94a905-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 | # Plowshare filebin.ca module
# Copyright (c) 2013 Plowshare team
#
# This file is part of Plowshare.
#
# Plowshare is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Plowshare is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Plowshare.  If not, see <http://www.gnu.org/licenses/>.
MODULE_FILEBIN_CA_REGEXP_URL='https\?://\(www\.\)\?filebin\.ca/[[:alnum:]]\+'
MODULE_FILEBIN_CA_DOWNLOAD_OPTIONS=""
MODULE_FILEBIN_CA_DOWNLOAD_RESUME=yes
MODULE_FILEBIN_CA_DOWNLOAD_FINAL_LINK_NEEDS_COOKIE=no
MODULE_FILEBIN_CA_DOWNLOAD_SUCCESSIVE_INTERVAL=
MODULE_FILEBIN_CA_UPLOAD_OPTIONS=""
MODULE_FILEBIN_CA_UPLOAD_REMOTE_SUPPORT=no
MODULE_FILEBIN_CA_PROBE_OPTIONS=""
# Output a filebin.ca file download URL
# $1: cookie file (unused here)
# $2: filebin.ca url
# stdout: real file download link
filebin_ca_download() {
    local -r URL=$2
    # Nothing to do, links are direct!
    echo "$URL"
}
# Upload a file to filebin.ca
# Official sources: https://github.com/slepp/filebin.ca
# $1: cookie file (unused here)
# $2: input file (with full path)
# $3: remote filename
filebin_ca_upload() {
    local -r FILE=$2
    local -r DESTFILE=$3
    local -r BASE_URL='http://filebin.ca/upload.php'
    local DATA STATUS
    # No API key for now..
    DATA=$(curl_with_log \
        -F "file=@$FILE;filename=$DESTFILE" \
        "$BASE_URL") || return
    if [ -z "$DATA" ]; then
        log_error 'Remote error: empty result not expected. Server busy?'
        return $ERR_LINK_TEMP_UNAVAILABLE
    fi
    # Result sample:
    # status:wjBQjTib7TH
    # url:http://filebin.ca/wjBQjTib7TH/foo.zip
    STATUS=$(parse '^status:' '^status:\(.*\)' <<< "$DATA") || return
    if [ "$STATUS" = 'error' -o "$STATUS" = 'fail' ]; then
        log_error 'Remote error'
        return $ERR_FATAL
    fi
    parse '^url:' '^url:\(http://[^[:space:]]\+\)' <<< "$DATA"
}
# Probe a download URL
# $1: cookie file (unused here)
# $2: filebin.ca url
# $3: requested capability list
# stdout: 1 capability per line
filebin_ca_probe() {
    local -r URL=$2
    local -r REQ_IN=$3
    local HEADERS REQ_OUT
    # Content-Type: application/octet-stream
    # Content-Disposition: attachment; filename="foo"
    # Content-length: 123456
    HEADERS=$(curl --head "$URL") || return
    if match '404 Not Found' "$HEADERS"; then
        return $ERR_LINK_DEAD
    fi
    REQ_OUT=c
    if [[ $REQ_IN = *f* ]]; then
        grep_http_header_content_disposition <<< "$HEADERS" && REQ_OUT="${REQ_OUT}f"
    fi
    if [[ $REQ_IN = *s* ]]; then
        grep_http_header_content_length <<< "$HEADERS" && REQ_OUT="${REQ_OUT}s"
    fi
    echo $REQ_OUT
}
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