gvisor/tools/nogo/defs.bzl

429 lines
15 KiB
Python

"""Nogo rules."""
load("//tools/bazeldefs:go.bzl", "go_context", "go_importpath", "go_rule", "go_test_library")
NogoConfigInfo = provider(
"information about a nogo configuration",
fields = {
"srcs": "the collection of configuration files",
},
)
def _nogo_config_impl(ctx):
return [NogoConfigInfo(
srcs = ctx.files.srcs,
)]
nogo_config = rule(
implementation = _nogo_config_impl,
attrs = {
"srcs": attr.label_list(
doc = "a list of yaml files (schema defined by tool/nogo/config.go).",
allow_files = True,
),
},
)
NogoTargetInfo = provider(
"information about the Go target",
fields = {
"goarch": "the build architecture (GOARCH)",
"goos": "the build OS target (GOOS)",
},
)
def _nogo_target_impl(ctx):
return [NogoTargetInfo(
goarch = ctx.attr.goarch,
goos = ctx.attr.goos,
)]
nogo_target = go_rule(
rule,
implementation = _nogo_target_impl,
attrs = {
"goarch": attr.string(
doc = "the Go build architecture (propagated to other rules).",
mandatory = True,
),
"goos": attr.string(
doc = "the Go OS target (propagated to other rules).",
mandatory = True,
),
},
)
def _nogo_objdump_tool_impl(ctx):
# Construct the magic dump command.
#
# Note that in some cases, the input is being fed into the tool via stdin.
# Unfortunately, the Go objdump tool expects to see a seekable file [1], so
# we need the tool to handle this case by creating a temporary file.
#
# [1] https://github.com/golang/go/issues/41051
nogo_target_info = ctx.attr._nogo_target[NogoTargetInfo]
go_ctx = go_context(ctx, goos = nogo_target_info.goos, goarch = nogo_target_info.goarch)
env_prefix = " ".join(["%s=%s" % (key, value) for (key, value) in go_ctx.env.items()])
dumper = ctx.actions.declare_file(ctx.label.name)
ctx.actions.write(dumper, "\n".join([
"#!/bin/bash",
"set -euo pipefail",
"if [[ $# -eq 0 ]]; then",
" T=$(mktemp -u -t libXXXXXX.a)",
" cat /dev/stdin > ${T}",
"else",
" T=$1;",
"fi",
"%s %s tool objdump ${T}" % (
env_prefix,
go_ctx.go.path,
),
"if [[ $# -eq 0 ]]; then",
" rm -rf ${T}",
"fi",
"",
]), is_executable = True)
# Include the full runfiles.
return [DefaultInfo(
runfiles = ctx.runfiles(files = go_ctx.runfiles.to_list()),
executable = dumper,
)]
nogo_objdump_tool = go_rule(
rule,
implementation = _nogo_objdump_tool_impl,
attrs = {
"_nogo_target": attr.label(
default = "//tools/nogo:target",
cfg = "target",
),
},
)
# NogoStdlibInfo is the set of standard library facts.
NogoStdlibInfo = provider(
"information for nogo analysis (standard library facts)",
fields = {
"facts": "serialized standard library facts",
"raw_findings": "raw package findings (if relevant)",
},
)
def _nogo_stdlib_impl(ctx):
# Build the standard library facts.
nogo_target_info = ctx.attr._nogo_target[NogoTargetInfo]
go_ctx = go_context(ctx, goos = nogo_target_info.goos, goarch = nogo_target_info.goarch)
facts = ctx.actions.declare_file(ctx.label.name + ".facts")
raw_findings = ctx.actions.declare_file(ctx.label.name + ".raw_findings")
config = struct(
Srcs = [f.path for f in go_ctx.stdlib_srcs],
GOOS = go_ctx.goos,
GOARCH = go_ctx.goarch,
Tags = go_ctx.tags,
)
config_file = ctx.actions.declare_file(ctx.label.name + ".cfg")
ctx.actions.write(config_file, config.to_json())
ctx.actions.run(
inputs = [config_file] + go_ctx.stdlib_srcs,
outputs = [facts, raw_findings],
tools = depset(go_ctx.runfiles.to_list() + ctx.files._nogo_objdump_tool),
executable = ctx.files._nogo_check[0],
mnemonic = "NogoStandardLibraryAnalysis",
progress_message = "Analyzing Go Standard Library",
arguments = go_ctx.nogo_args + [
"-objdump_tool=%s" % ctx.files._nogo_objdump_tool[0].path,
"-stdlib=%s" % config_file.path,
"-findings=%s" % raw_findings.path,
"-facts=%s" % facts.path,
],
)
# Return the stdlib facts as output.
return [NogoStdlibInfo(
facts = facts,
raw_findings = raw_findings,
)]
nogo_stdlib = go_rule(
rule,
implementation = _nogo_stdlib_impl,
attrs = {
"_nogo_check": attr.label(
default = "//tools/nogo/check:check",
cfg = "host",
),
"_nogo_objdump_tool": attr.label(
default = "//tools/nogo:objdump_tool",
cfg = "host",
),
"_nogo_target": attr.label(
default = "//tools/nogo:target",
cfg = "target",
),
},
)
# NogoInfo is the serialized set of package facts for a nogo analysis.
#
# Each go_library rule will generate a corresponding nogo rule, which will run
# with the source files as input. Note however, that the individual nogo rules
# are simply stubs that enter into the shadow dependency tree (the "aspect").
NogoInfo = provider(
"information for nogo analysis",
fields = {
"facts": "serialized package facts",
"raw_findings": "raw package findings (if relevant)",
"escapes": "escape-only findings (if relevant)",
"importpath": "package import path",
"binaries": "package binary files",
"srcs": "srcs (for go_test support)",
"deps": "deps (for go_test support)",
},
)
def _nogo_aspect_impl(target, ctx):
# If this is a nogo rule itself (and not the shadow of a go_library or
# go_binary rule created by such a rule), then we simply return nothing.
# All work is done in the shadow properties for go rules. For a proto
# library, we simply skip the analysis portion but still need to return a
# valid NogoInfo to reference the generated binary.
if ctx.rule.kind in ("go_library", "go_tool_library", "go_binary", "go_test"):
srcs = ctx.rule.files.srcs
deps = ctx.rule.attr.deps
elif ctx.rule.kind in ("go_proto_library", "go_wrap_cc"):
srcs = []
deps = ctx.rule.attr.deps
else:
return [NogoInfo()]
# If we're using the "library" attribute, then we need to aggregate the
# original library sources and dependencies into this target to perform
# proper type analysis.
if ctx.rule.kind == "go_test":
library = go_test_library(ctx.rule)
if library != None:
info = library[NogoInfo]
if hasattr(info, "srcs"):
srcs = srcs + info.srcs
if hasattr(info, "deps"):
deps = deps + info.deps
# Start with all target files and srcs as input.
inputs = target.files.to_list() + srcs
# Generate a shell script that dumps the binary. Annoyingly, this seems
# necessary as the context in which a run_shell command runs does not seem
# to cleanly allow us redirect stdout to the actual output file. Perhaps
# I'm missing something here, but the intermediate script does work.
binaries = target.files.to_list()
objfiles = [f for f in binaries if f.path.endswith(".a")]
if len(objfiles) > 0:
# Prefer the .a files for go_library targets.
target_objfile = objfiles[0]
else:
# Use the raw binary for go_binary and go_test targets.
target_objfile = binaries[0]
inputs.append(target_objfile)
# Extract the importpath for this package.
if ctx.rule.kind == "go_test":
# If this is a test, then it will not be imported by anything else.
# We can safely set the importapth to just "test". Note that this
# is necessary if the library also imports the core library (in
# addition to including the sources directly), which happens in
# some complex cases (seccomp_victim).
importpath = "test"
else:
importpath = go_importpath(target)
# Collect all info from shadow dependencies.
fact_map = dict()
import_map = dict()
all_raw_findings = []
for dep in deps:
# There will be no file attribute set for all transitive dependencies
# that are not go_library or go_binary rules, such as a proto rules.
# This is handled by the ctx.rule.kind check above.
info = dep[NogoInfo]
if not hasattr(info, "facts"):
continue
# Configure where to find the binary & fact files. Note that this will
# use .x and .a regardless of whether this is a go_binary rule, since
# these dependencies must be go_library rules.
x_files = [f.path for f in info.binaries if f.path.endswith(".x")]
if not len(x_files):
x_files = [f.path for f in info.binaries if f.path.endswith(".a")]
import_map[info.importpath] = x_files[0]
fact_map[info.importpath] = info.facts.path
# Collect all findings; duplicates are resolved at the end.
all_raw_findings.extend(info.raw_findings)
# Ensure the above are available as inputs.
inputs.append(info.facts)
inputs += info.binaries
# Add the standard library facts.
stdlib_info = ctx.attr._nogo_stdlib[NogoStdlibInfo]
stdlib_facts = stdlib_info.facts
inputs.append(stdlib_facts)
# The nogo tool operates on a configuration serialized in JSON format.
nogo_target_info = ctx.attr._nogo_target[NogoTargetInfo]
go_ctx = go_context(ctx, goos = nogo_target_info.goos, goarch = nogo_target_info.goarch)
facts = ctx.actions.declare_file(target.label.name + ".facts")
raw_findings = ctx.actions.declare_file(target.label.name + ".raw_findings")
escapes = ctx.actions.declare_file(target.label.name + ".escapes")
config = struct(
ImportPath = importpath,
GoFiles = [src.path for src in srcs if src.path.endswith(".go")],
NonGoFiles = [src.path for src in srcs if not src.path.endswith(".go")],
GOOS = go_ctx.goos,
GOARCH = go_ctx.goarch,
Tags = go_ctx.tags,
FactMap = fact_map,
ImportMap = import_map,
StdlibFacts = stdlib_facts.path,
)
config_file = ctx.actions.declare_file(target.label.name + ".cfg")
ctx.actions.write(config_file, config.to_json())
inputs.append(config_file)
ctx.actions.run(
inputs = inputs,
outputs = [facts, raw_findings, escapes],
tools = depset(go_ctx.runfiles.to_list() + ctx.files._nogo_objdump_tool),
executable = ctx.files._nogo_check[0],
mnemonic = "NogoAnalysis",
progress_message = "Analyzing %s" % target.label,
arguments = go_ctx.nogo_args + [
"-binary=%s" % target_objfile.path,
"-objdump_tool=%s" % ctx.files._nogo_objdump_tool[0].path,
"-package=%s" % config_file.path,
"-findings=%s" % raw_findings.path,
"-facts=%s" % facts.path,
"-escapes=%s" % escapes.path,
],
)
# Flatten all findings from all dependencies.
#
# This is done because all the filtering must be done at the
# top-level nogo_test to dynamically apply a configuration.
# This does not actually add any additional work here, but
# will simply propagate the full list of files.
all_raw_findings = [stdlib_info.raw_findings] + depset(all_raw_findings).to_list() + [raw_findings]
# Return the package facts as output.
return [NogoInfo(
facts = facts,
raw_findings = all_raw_findings,
escapes = escapes,
importpath = importpath,
binaries = binaries,
srcs = srcs,
deps = deps,
)]
nogo_aspect = go_rule(
aspect,
implementation = _nogo_aspect_impl,
attr_aspects = [
"deps",
"library",
"embed",
],
attrs = {
"_nogo_check": attr.label(
default = "//tools/nogo/check:check",
cfg = "host",
),
"_nogo_stdlib": attr.label(
default = "//tools/nogo:stdlib",
cfg = "host",
),
"_nogo_objdump_tool": attr.label(
default = "//tools/nogo:objdump_tool",
cfg = "host",
),
"_nogo_target": attr.label(
default = "//tools/nogo:target",
cfg = "target",
),
},
)
def _nogo_test_impl(ctx):
"""Check nogo findings."""
# Ensure there's a single dependency.
if len(ctx.attr.deps) != 1:
fail("nogo_test requires exactly one dep.")
raw_findings = ctx.attr.deps[0][NogoInfo].raw_findings
escapes = ctx.attr.deps[0][NogoInfo].escapes
# Build a step that applies the configuration.
config_srcs = ctx.attr.config[NogoConfigInfo].srcs
findings = ctx.actions.declare_file(ctx.label.name + ".findings")
ctx.actions.run(
inputs = raw_findings + ctx.files.srcs + config_srcs,
outputs = [findings],
tools = depset(ctx.files._filter),
executable = ctx.files._filter[0],
mnemonic = "GoStaticAnalysis",
progress_message = "Generating %s" % ctx.label,
arguments = ["-input=%s" % f.path for f in raw_findings] +
["-config=%s" % f.path for f in config_srcs] +
["-output=%s" % findings.path],
)
# Build a runner that checks the filtered facts.
#
# Note that this calls the filter binary without any configuration, so all
# findings will be included. But this is expected, since we've already
# filtered out everything that should not be included.
runner = ctx.actions.declare_file(ctx.label.name)
runner_content = [
"#!/bin/bash",
"exec %s -input=%s" % (ctx.files._filter[0].short_path, findings.short_path),
"",
]
ctx.actions.write(runner, "\n".join(runner_content), is_executable = True)
return [DefaultInfo(
# The runner just executes the filter again, on the
# newly generated filtered findings. We still need
# the filter tool as part of our runfiles, however.
runfiles = ctx.runfiles(files = ctx.files._filter + [findings]),
executable = runner,
), OutputGroupInfo(
# Propagate the filtered filters, for consumption by
# build tooling. Note that the build tooling typically
# pays attention to the mnemoic above, so this must be
# what is expected by the tooling.
nogo_findings = depset([findings]),
# Expose all escape analysis findings (see above).
nogo_escapes = depset([escapes]),
)]
nogo_test = rule(
implementation = _nogo_test_impl,
attrs = {
"config": attr.label(
mandatory = True,
doc = "A rule of kind nogo_config.",
),
"deps": attr.label_list(
aspects = [nogo_aspect],
doc = "Exactly one Go dependency to be analyzed.",
),
"srcs": attr.label_list(
allow_files = True,
doc = "Relevant src files. This is ignored except to make the nogo_test directly affected by the files.",
),
"_filter": attr.label(default = "//tools/nogo/filter:filter"),
},
test = True,
)