WIP

2026-07-20 00:56:41 +03:00
parent d906e14afe
commit 2bf8c8ede3
10 changed files with 1362 additions and 0 deletions
@@ -0,0 +1,126 @@
+#!/bin/bash
+
+rpm_safe_symlink_target()
+{
+    local root=$1 relative_path=$2 link_target=$3
+    local canonical_root link_directory resolved_target
+
+    canonical_root=$(realpath -m -- "$root") || return 1
+    link_directory=$(realpath -m -- "$canonical_root/$(dirname -- "$relative_path")") || return 1
+
+    if [[ $link_target == /* ]]; then
+        resolved_target=$(realpath -m -- "$canonical_root/${link_target#/}") || return 1
+    else
+        resolved_target=$(realpath -m -- "$link_directory/$link_target") || return 1
+    fi
+
+    [[ $resolved_target == "$canonical_root" || $resolved_target == "$canonical_root"/* ]] || return 1
+
+    if [[ $link_target == /* ]]; then
+        realpath -m --relative-to="$link_directory" -- "$resolved_target"
+    else
+        printf '%s\n' "$link_target"
+    fi
+}
+
+rpm_cpio_literal_pattern()
+{
+    local input=$1 output= character index
+
+    [[ $input != *$'\n'* && $input != *$'\r'* ]] || return 1
+    for ((index = 0; index < ${#input}; ++index)); do
+        character=${input:index:1}
+        case $character in
+            '[') output+='[[]' ;;
+            ']') output+='[]]' ;;
+            '*') output+='[*]' ;;
+            '?') output+='[?]' ;;
+            '\\') output+='[\\]' ;;
+            *) output+=$character ;;
+        esac
+    done
+    printf '%s\n' "$output"
+}
+
+rpm_split_file_record()
+{
+    local record=$1 separator=$'\034'
+
+    RPM_FILENAME=
+    RPM_LINK_TARGET=
+    [[ $record == *"$separator"* ]] || return 1
+    RPM_FILENAME=${record%%"$separator"*}
+    RPM_LINK_TARGET=${record#*"$separator"}
+    [[ $RPM_LINK_TARGET != *"$separator"* ]] || return 1
+    [[ $RPM_FILENAME != *$'\t'* && $RPM_FILENAME != *$'\n'* && $RPM_FILENAME != *$'\r'* ]] || return 1
+    [[ $RPM_LINK_TARGET != *$'\t'* && $RPM_LINK_TARGET != *$'\n'* && $RPM_LINK_TARGET != *$'\r'* ]] || return 1
+}
+
+rpm_install_symlink_manifest()
+{
+    local root=$1 manifest=$2 log=$3 separator=$'\034'
+    local canonical_root sorted row relative link_target safe_target destination parent existing
+
+    canonical_root=$(realpath -m -- "$root") || return 1
+
+    sorted=$(mktemp "${manifest}.sorted.XXXXXX") || return 1
+    if ! awk -F '\t' -v separator="$separator" '
+        NF >= 2 {
+            path=$1
+            depth=gsub(/\//, "/", path)
+            printf "%08d%s%s\n", depth, separator, $0
+        }
+    ' "$manifest" | LC_ALL=C sort -t "$separator" -k1,1n -k2,2 >"$sorted"; then
+        rm -f -- "$sorted"
+        return 1
+    fi
+
+    while IFS=$separator read -r _depth row; do
+        IFS=$'\t' read -r relative link_target <<<"$row"
+        [[ -n $relative && -n $link_target ]] || continue
+        destination=$canonical_root/$relative
+        parent=$(realpath -m -- "$(dirname -- "$destination")") || {
+            rm -f -- "$sorted"
+            return 1
+        }
+        [[ $parent == "$canonical_root" || $parent == "$canonical_root"/* ]] || {
+            printf 'escaping RPM symlink parent rejected: %q\n' "/$relative" >>"$log"
+            rm -f -- "$sorted"
+            return 1
+        }
+        if ! safe_target=$(rpm_safe_symlink_target "$canonical_root" "$relative" "$link_target"); then
+            printf 'escaping RPM symlink rejected: %q -> %q\n' "/$relative" "$link_target" >>"$log"
+            rm -f -- "$sorted"
+            return 1
+        fi
+        mkdir -p -- "$parent" || {
+            rm -f -- "$sorted"
+            return 1
+        }
+
+        if [[ -L $destination ]]; then
+            existing=$(readlink -- "$destination") || {
+                rm -f -- "$sorted"
+                return 1
+            }
+            if [[ $existing == "$safe_target" ]]; then
+                continue
+            fi
+            printf 'conflicting RPM symlinks: %q -> %q and %q\n' \
+                "/$relative" "$existing" "$safe_target" >>"$log"
+            rm -f -- "$sorted"
+            return 1
+        elif [[ -e $destination ]]; then
+            printf 'RPM symlink conflicts with existing path: %q\n' "/$relative" >>"$log"
+            rm -f -- "$sorted"
+            return 1
+        fi
+        if ! ln -s -- "$safe_target" "$destination"; then
+            printf 'unable to create RPM symlink: %q -> %q\n' "/$relative" "$safe_target" >>"$log"
+            rm -f -- "$sorted"
+            return 1
+        fi
+    done <"$sorted"
+
+    rm -f -- "$sorted"
+}