Bazel: pull in some dependencies to the internal repo

This allows to build the ruby and python packs
(and the upcoming experimental rust one) from
within `codeql`.

misc/bazel/glibc_symbols_check.bzl

@@ -0,0 +1,19 @@
+load("@rules_python//python:defs.bzl", "py_test")
+
+def glibc_symbols_check(name, binary):
+    """
+    Checks that the supplied binary doesn't use symbols that are not available in older glibc versions.
+    """
+    # Note this accesses system binaries that are not declared anywhere,
+    # thus breaking build hermeticity
+
+    py_test(
+        name = name,
+        srcs = ["//misc/bazel/internal:check_glibc_symbols.py"],
+        main = "//misc/bazel/internal:check_glibc_symbols.py",
+        data = [binary],
+        args = ["$(location :%s)" % binary],
+        target_compatible_with = ["@platforms//os:linux", "//misc/bazel/platforms:bundled"],
+        size = "medium",
+        tags = ["glibc-symbols-check"],
+    )

misc/bazel/internal/BUILD.bazel

@@ -1 +1 @@
-exports_files(["install.py"])
+exports_files(glob(["*.py"]))

misc/bazel/internal/check_glibc_symbols.py

@@ -0,0 +1,172 @@
+#!/usr/bin/env python
+
+import re
+import subprocess
+import sys
+import os
+import argparse
+
+# Some of these limits are conservative and the required versions could be
+# comfortably increased, especially if they're no newer than the versions that
+# Java depends on.
+default_limits = {
+    'GCC': '3.0',
+
+    # Default limit for versions of GLIBC symbols used by target program.
+    # GLIBC_2.17 was released on 2012-12-25.
+    # https://sourceware.org/glibc/wiki/Glibc%20Timeline
+    'GLIBC': '2.17',
+
+    # Default limit for versions of GLIBCXX (and GLIBCPP) symbols used
+    # by target program. GLIBCXX_3.4 implies at least libstdc++.6.0,
+    # and was adopted by GCC 3.4, release on 18/4/2004.
+    # https://gcc.gnu.org/onlinedocs/libstdc++/manual/abi.html
+    'GLIBCXX': '3.4',
+    'GLIBCPP': '3.4',
+    'CXXABI': '1.3',
+}
+
+# List of libraries which must not be dynamically loaded
+# On linux, the llvm libc++ libraries are statically linked and should not appear
+# in the output of `ldd`
+no_dynlink_libs = [
+  "libstdc++",
+  "libc++",
+  "libc++abi",
+  "libunwind",
+]
+
+def get_glibc_version():
+  version = subprocess.check_output(['ldd', '--version']).decode("utf-8").split('\n')[0]
+  return float(version.split(' ')[-1])
+
+def isTrue(var):
+  return var in os.environ and os.environ[var].lower() in ['true', 'yes', '1']
+
+def memoize(f):
+  '''Memoize decorator'''
+  memo = {}
+  def helper(x):
+    if x not in memo:
+      memo[x] = f(x)
+    return memo[x]
+  return helper
+
+def normalise_ver(ver):
+  '''Convert a dot delimited numerical version string into list of integers.
+
+     This conversion facilitates comparisons between version numbers.'''
+  return [int(p) for p in ver.split('.')]
+
+def too_new(cat, ver, limits):
+  '''Compare version string ver with the limit for cat.
+     Return True if ver is greater than the limit, or if there is no limit for cat.'''
+  if cat in limits:
+    limit = limits[cat]
+    return normalise_ver(ver) > normalise_ver(limit)
+  else:
+    return True
+
+@memoize
+def get_libs(prog):
+  '''Get list of dynamically linked libraries'''
+  # Find paths to all libraries linked
+  re_lib = re.compile('^.* (/.*) \(0x[0-9a-f]+\)$')
+  try:
+    subprocess.check_output(['ldd', prog], stderr=subprocess.STDOUT).decode('utf-8').split('\n')
+  except subprocess.CalledProcessError as e:
+    # ldd will have a non zero exitcode of the binary is not dynamically linked.
+    return []
+  except:
+    raise
+
+  return [m.group(1) for m in [ re_lib.search(l) for l in subprocess.check_output(['ldd', prog]).decode('utf-8').split('\n') ] if m]
+
+def gather_min_symbol_versions(prog, limits):
+  '''Inspect the given executable 'prog' using `ldd` to discover which libraries it is linked
+     against. For each library, use `readelf` to discover the symbols therein, and for each
+     symbol with a GLIBC, GLIBCXX or GLIBCPP version record the latest version of each symbol
+     found that does not exceed the given limits, or the earliest available version if no
+     version is found within the limits.
+
+     Return a dict mapping symbol names to strings of the form "GLIBC_2.5". The dict
+     thus indicates the earliest available versions of each symbol.'''
+  libs = get_libs(prog)
+  # Find earliest versions of all symbols
+  sym_ver = dict()
+  re_sym = re.compile('(\\w+)@+(.+)_([0-9.]+)')
+  for lib in libs:
+    for (sym, cat, ver) in re.findall(re_sym, subprocess.check_output(['readelf', '-Ws', lib]).decode('utf-8')):
+      if sym in sym_ver:
+         (cat2, ver2) = sym_ver[sym]
+         if cat != cat2:
+           raise Exception('Mismatched categories for symbol: ' + str(sym, cat, ver, cat2, ver2))
+         if (normalise_ver(ver) < normalise_ver(ver2) and     too_new(cat2, ver2, limits)) or \
+            (normalise_ver(ver) > normalise_ver(ver2) and not too_new(cat, ver, limits)):
+           sym_ver[sym] = (cat, ver)
+      else:
+        sym_ver[sym] = (cat, ver)
+  return sym_ver
+
+def gather_linked_symbols(prog):
+  '''Inspect the given executable 'prog' using `nm` to discover which symbols it links,
+     and for each symbol with a GLIBC, GLIBCXX, or GLIBCPP version record the version
+     in a dict mapping symbol names to versions.'''
+  re_obj  = re.compile('U (\\w+)@+(.+)_([0-9.]+)')
+  return re_obj.findall(subprocess.check_output(['nm', '-u', prog]).decode('utf-8'))
+
+def verify_dynlinked_libraries(prog):
+  '''Return the intersection set between dynamically linked libraries
+     that should not be dynamically loaded. See `no_dynlink_libs`.'''
+  libs = get_libs(prog)
+  bad_libs = []
+  for lib in libs:
+    lib_name = os.path.basename(lib).split(".")[0]
+    if lib_name in no_dynlink_libs:
+      bad_libs += [lib]
+
+  return bad_libs
+
+def main():
+  if isTrue('CODEQL_SKIP_COMPATIBILITY') and not isTrue('CI'):
+    # Respect CODEQL_SKIP_COMPATIBILITY which tells us to skip this check, unless we are on CI
+    sys.exit(0)
+
+  # Verify parameters
+  parser = argparse.ArgumentParser()
+  parser.add_argument("program")
+  # create outfile - this is needed for the bazel aspect integration
+  parser.add_argument("output", nargs="?", type=argparse.FileType('w'))
+  prog = parser.parse_args().program
+
+  # Gather versions of symbols actually linked
+  prog_symbols = gather_linked_symbols(prog)
+  # Check whether any symbols exceed the maximum version restrictions
+  bad_syms = [ (sym, cat, ver) for sym, cat, ver in prog_symbols if too_new(cat, ver, default_limits) ]
+  if bad_syms != []:
+    # Scan for minimum versions of symbols available in linked libraries
+    available_symbols = gather_min_symbol_versions(prog, default_limits)
+    for sym, cat, ver in bad_syms:
+      print(sym + ' is too new or from an unknown category: it requires ' + cat + '_' + ver
+                + ', but we are limited to ' + str(default_limits))
+    if sym in available_symbols:
+      (cat, ver) = available_symbols[sym]
+      if not too_new(cat, ver, default_limits):
+        print('\tconsider adding: SET_GLIBC_VERSION(%s_%s,%s) { ... } to glibc_compatibility.cpp, ' % (cat, ver, sym))
+        print('\tand add \'-Wl,--wrap=%s\' when linking. ' % (sym))
+      else:
+        print('\tThe earliest available symbol has version %s_%s' % (cat, ver))
+
+  bad_libs = verify_dynlinked_libraries(prog)
+  if bad_libs != []:
+    print("Binary dynamically links against:")
+    for bad_lib in bad_libs:
+      print("\t%s" % (bad_lib))
+    print("These libraries should be statically linked on linux")
+
+  if bad_syms != [] or bad_libs != []:
+    sys.exit(1)
+  sys.exit(0)
+
+if __name__ == '__main__':
+    main()

misc/bazel/lipo.bzl

@@ -0,0 +1,44 @@
+load("@bazel_skylib//lib:paths.bzl", "paths")
+load("//misc/bazel:transitions.bzl", "forward_binary_from_transition", "get_transition_attrs", "universal_binary_transition")
+
+def _universal_binary_impl(ctx):
+    # Two cases: Either we're on macos, and we need to lipo the two binaries that the transition generated
+    # together, or we're on another platform, where we just copy along the binary, and forward the DefaultInfo data
+    binaries = [dep[DefaultInfo].files_to_run.executable for dep in ctx.attr.dep]
+    if len(binaries) == 0:
+        fail("No executable inputs found")
+
+    (_, extension) = paths.split_extension(binaries[0].basename)
+    new_executable = ctx.actions.declare_file(ctx.label.name + extension)
+
+    # We're using a split transition on the `dep` attribute on macos. If we are on macos, that has the function that
+    # a) ctx.split_attr has two entries (if we need to retrieve the per-architecture binaries), and that
+    # ctx.addr.dep is a list with two elements - one for each platform.
+    # While not using a split transition, ctx.attr.dep is a list with one element, as we just have a single platform.
+    # We use this to distinguish whether we should lipo the binaries together, or just forward the binary.
+    if len(binaries) == 1:
+        return forward_binary_from_transition(ctx)
+    else:
+        ctx.actions.run_shell(
+            inputs = binaries,
+            outputs = [new_executable],
+            command = "lipo -create %s -output %s" % (" ".join([binary.path for binary in binaries]), new_executable.path),
+        )
+    files = depset(direct = [new_executable])
+    runfiles = ctx.runfiles([new_executable]).merge_all([dep[DefaultInfo].default_runfiles for dep in ctx.attr.dep])
+
+    providers = [
+        DefaultInfo(
+            files = files,
+            runfiles = runfiles,
+            executable = new_executable,
+        ),
+    ]
+    return providers
+
+universal_binary = rule(
+    implementation = _universal_binary_impl,
+    attrs = get_transition_attrs(universal_binary_transition),
+    doc = """On macOS: Create a universal (fat) binary from the input rule, by applying two transitions and lipoing the result together.
+    No-op on other platforms, just forward the binary.""",
+)

misc/bazel/platforms/BUILD.bazel

@@ -0,0 +1,66 @@
+package(default_visibility = ["//visibility:public"])
+
+constraint_setting(name = "host_or_bundled")
+
+constraint_value(
+    name = "bundled",
+    constraint_setting = ":host_or_bundled",
+)
+
+constraint_value(
+    name = "host",
+    constraint_setting = ":host_or_bundled",
+)
+
+alias(
+    name = "detected",
+    actual = "@local_config_platform//:host",
+)
+
+platform(
+    name = "bundled_toolchain",
+    constraint_values = [":bundled"],
+    parents = [":detected"],
+)
+
+platform(
+    name = "bundled_toolchain_arm64",
+    constraint_values = ["@platforms//cpu:arm64"],
+    parents = [":bundled_toolchain"],
+)
+
+platform(
+    name = "bundled_toolchain_x86_64",
+    constraint_values = ["@platforms//cpu:x86_64"],
+    parents = [":bundled_toolchain"],
+)
+
+platform(
+    name = "bundled_toolchain_x86_32",
+    constraint_values = ["@platforms//cpu:x86_32"],
+    parents = [":bundled_toolchain"],
+)
+
+platform(
+    name = "host_toolchain",
+    constraint_values = [":host"],
+    parents = [":detected"],
+)
+
+platform(
+    name = "host_toolchain_arm64",
+    constraint_values = ["@platforms//cpu:arm64"],
+    parents = [":host_toolchain"],
+)
+
+platform(
+    name = "host_toolchain_x86_64",
+    constraint_values = ["@platforms//cpu:x86_64"],
+    parents = [":host_toolchain"],
+)
+
+platform(
+    name = "host_toolchain_x86_32",
+    constraint_values = ["@platforms//cpu:x86_32"],
+    parents = [":host_toolchain"],
+)

misc/bazel/rust.bzl

@@ -1,6 +1,6 @@
 load("@rules_rust//rust:defs.bzl", "rust_binary")
-load("@semmle_code//buildutils-internal:glibc_symbols_check.bzl", "glibc_symbols_check")
-load("@semmle_code//buildutils-internal:lipo.bzl", "universal_binary")
+load("//misc/bazel:glibc_symbols_check.bzl", "glibc_symbols_check")
+load("//misc/bazel:lipo.bzl", "universal_binary")
 
 def codeql_rust_binary(
         name,