modules.d/45url-lib/url-lib.sh

   1 #!/bin/sh
   2 # url-lib.sh - functions for handling URLs (file fetching etc.)
   3 #
   4 # Authors:
   5 #   Will Woods <wwoods@redhat.com>
   6
   7 type mkuniqdir > /dev/null 2>&1 || . /lib/dracut-lib.sh
   8
   9 # fetch_url URL [OUTFILE]
  10 #   fetch the given URL to a locally-visible location.
  11 #   if OUTFILE is given, the URL will be fetched to that filename,
  12 #   overwriting it if present.
  13 #   If the URL is something mountable (e.g. nfs://) and no OUTFILE is given,
  14 #   the server will be left mounted until pre-pivot.
  15 #   the return values are as follows:
  16 #   0: success
  17 #   253: unknown error (file missing)
  18 #   254: unhandled URL scheme / protocol
  19 #   255: bad arguments / unparsable URLs
  20 #   other: fetch command failure (whatever curl/mount/etc return)
  21 fetch_url() {
  22     local url="$1" outloc="$2"
  23     local handler
  24     handler="$(get_url_handler "$url")"
  25     [ -n "$handler" ] || return 254
  26     [ -n "$url" ] || return 255
  27     "$handler" "$url" "$outloc"
  28 }
  29
  30 # get_url_handler URL
  31 #   returns the first HANDLERNAME corresponding to the URL's scheme
  32 get_url_handler() {
  33     local scheme="${1%%:*}" item=""
  34     for item in $url_handler_map; do
  35         [ "$scheme" = "${item%%:*}" ] && echo "${item#*:}" && return 0
  36     done
  37     return 1
  38 }
  39
  40 # add_url_handler HANDLERNAME SCHEME [SCHEME...]
  41 #   associate the named handler with the named scheme(s).
  42 add_url_handler() {
  43     local handler="$1"
  44     shift
  45     local schemes="$*" scheme=""
  46     set --
  47     for scheme in $schemes; do
  48         [ "$(get_url_handler "$scheme")" = "$handler" ] && continue
  49         set -- "$@" "$scheme:$handler"
  50     done
  51     set -- "$@" "$url_handler_map" # add new items to *front* of list
  52     url_handler_map="$*"
  53 }
  54
  55 ### HTTP, HTTPS, FTP #################################################
  56
  57 export CURL_HOME="/run/initramfs/url-lib"
  58 mkdir -p $CURL_HOME
  59 curl_args="--globoff --location --retry 3 --retry-connrefused --fail --show-error"
  60 getargbool 0 rd.noverifyssl && curl_args="$curl_args --insecure"
  61
  62 proxy=$(getarg proxy=)
  63 [ -n "$proxy" ] && curl_args="$curl_args --proxy $proxy"
  64
  65 curl_fetch_url() {
  66     local url="$1" outloc="$2"
  67     echo "$url" > /proc/self/fd/0
  68     if [ -n "$outloc" ]; then
  69         # shellcheck disable=SC2086
  70         curl $curl_args --output "$outloc" -- "$url" || return $?
  71     else
  72         local outdir
  73         outdir="$(mkuniqdir /tmp curl_fetch_url)"
  74         (
  75             cd "$outdir" || exit
  76             # shellcheck disable=SC2086
  77             curl $curl_args --remote-name "$url" || return $?
  78         )
  79         outloc="$outdir/$(ls -A "$outdir")"
  80     fi
  81     if ! [ -f "$outloc" ]; then
  82         warn "Downloading '$url' failed!"
  83         return 253
  84     fi
  85     if [ -z "$2" ]; then echo "$outloc"; fi
  86 }
  87 add_url_handler curl_fetch_url http https ftp tftp
  88
  89 set_http_header() {
  90     echo "header = \"$1: $2\"" >> $CURL_HOME/.curlrc
  91 }
  92
  93 ### TORRENT ##########################################################
  94
  95 ctorrent_args="-E 0 -e 0"
  96
  97 ctorrent_fetch_url() {
  98     local url="$1" outloc="$2"
  99     url=${url#*//}
 100     torrent_outloc="$outloc.torrent"
 101     echo "$url" > /proc/self/fd/0
 102     if [ -n "$outloc" ]; then
 103         # shellcheck disable=SC2086
 104         curl $curl_args --output "$torrent_outloc" -- "$url" || return $?
 105     else
 106         local outdir
 107         outdir="$(mkuniqdir /tmp torrent_fetch_url)"
 108         (
 109             cd "$outdir" || exit
 110             # shellcheck disable=SC2086
 111             curl $curl_args --remote-name "$url" || return $?
 112         )
 113         torrent_outloc="$outdir/$(ls -A "$outdir")"
 114         outloc=${torrent_outloc%.*}
 115     fi
 116     if ! [ -f "$torrent_outloc" ]; then
 117         warn "Downloading '$url' failed!"
 118         return 253
 119     fi
 120     # shellcheck disable=SC2086
 121     ctorrent $ctorrent_args -s "$outloc" "$torrent_outloc" >&2
 122     if ! [ -f "$outloc" ]; then
 123         warn "Torrent download of '$url' failed!"
 124         return 253
 125     fi
 126     if [ -z "$2" ]; then echo "$outloc"; fi
 127 }
 128
 129 command -v ctorrent > /dev/null \
 130     && add_url_handler ctorrent_fetch_url torrent
 131
 132 ### NFS ##############################################################
 133
 134 [ -e /lib/nfs-lib.sh ] && . /lib/nfs-lib.sh
 135
 136 nfs_already_mounted() {
 137     local server="$1" path="$2" s="" p=""
 138     while read -r src mnt rest || [ -n "$src" ]; do
 139         splitsep ":" "$src" s p
 140         p=${p%/}
 141         if [ "$server" = "$s" ]; then
 142             if [ "$path" = "$p" ]; then
 143                 echo "$mnt"
 144             elif str_starts "$path" "$p"; then
 145                 echo "$mnt"/"${path#"$p"/}"
 146             fi
 147         fi
 148     done < /proc/mounts
 149 }
 150
 151 nfs_fetch_url() {
 152     local url="$1" outloc="$2" nfs="" server="" path="" options=""
 153     nfs_to_var "$url" || return 255
 154     local filepath="${path%/*}" filename="${path##*/}" mntdir=""
 155
 156     # skip mount if server:/filepath is already mounted
 157     mntdir=$(nfs_already_mounted "$server" "$filepath")
 158     if [ -z "$mntdir" ]; then
 159         local mntdir
 160         mntdir="$(mkuniqdir /run nfs_mnt)"
 161         mount_nfs "$nfs:$server:$filepath${options:+:$options}" "$mntdir"
 162         # lazy unmount during pre-pivot hook
 163         inst_hook --hook pre-pivot --name 99url-lib-umount-nfs-"$(basename "$mntdir")" umount -l -- "$mntdir"
 164     fi
 165
 166     if [ -z "$outloc" ]; then
 167         outloc="$mntdir/$filename"
 168     else
 169         cp -f -- "$mntdir/$filename" "$outloc" || return $?
 170     fi
 171     [ -f "$outloc" ] || return 253
 172     if [ -z "$2" ]; then echo "$outloc"; fi
 173 }
 174 command -v nfs_to_var > /dev/null && add_url_handler nfs_fetch_url nfs nfs4