ooni-probe-cli/internal/netxlite/getaddrinfo_linux_test.go
Simone Basso cf6dbe48e0
netxlite: call getaddrinfo and handle platform-specific oddities (#764)
This commit changes our system resolver to call getaddrinfo directly when CGO is enabled. This change allows us to:

1. obtain the CNAME easily

2. obtain the real getaddrinfo retval

3. handle platform specific oddities such as `EAI_NODATA`
returned on Android devices

See https://github.com/ooni/probe/issues/2029 and https://github.com/ooni/probe/issues/2029#issuecomment-1140258729 in particular.

See https://github.com/ooni/probe/issues/2033 for documentation regarding the desire to see `getaddrinfo`'s retval.

See https://github.com/ooni/probe/issues/2118 for possible follow-up changes.
2022-05-28 15:10:30 +02:00

182 lines
3.6 KiB
Go

//go:build cgo && linux
package netxlite
import (
"errors"
"runtime"
"syscall"
"testing"
)
func TestGetaddrinfoAIFlags(t *testing.T) {
var wrong bool
switch runtime.GOOS {
case "android":
wrong = getaddrinfoAIFlags != aiCanonname
default:
wrong = getaddrinfoAIFlags != (aiCanonname | aiV4Mapped | aiAll)
}
if wrong {
t.Fatal("wrong flags for platform")
}
}
func TestGetaddrinfoGetPlatformSpecificAiFlags(t *testing.T) {
type args struct {
goos string
}
type expects struct {
flags int64
}
var inputs = []struct {
name string
args args
expects expects
}{{
name: "using the Android platform",
args: args{
goos: "android",
},
expects: expects{
flags: aiCanonname,
},
}, {
name: "using Linux",
args: args{
goos: "linux",
},
expects: expects{
flags: aiCanonname | aiV4Mapped | aiAll,
},
}, {
name: "when the platform name is empty",
args: args{
goos: "",
},
expects: expects{
flags: aiCanonname | aiV4Mapped | aiAll,
},
}}
for _, input := range inputs {
t.Run(input.name, func(t *testing.T) {
flags := getaddrinfoGetPlatformSpecificAIFlags(input.args.goos)
if int64(flags) != input.expects.flags {
t.Fatal("invalid flags")
}
})
}
}
func TestGetaddrinfoStateToError(t *testing.T) {
type args struct {
code int64
err error
goos string
}
type expects struct {
message string // message obtained using .Error
code int64
err error
}
var inputs = []struct {
name string
args args
expects expects
}{{
name: "with C.EAI_SYSTEM and non-nil error",
args: args{
code: eaiSystem,
err: syscall.EAGAIN,
goos: "linux",
},
expects: expects{
message: syscall.EAGAIN.Error(),
code: eaiSystem,
err: syscall.EAGAIN,
},
}, {
name: "with C.EAI_SYSTEM and nil error",
args: args{
code: eaiSystem,
err: nil,
goos: "linux",
},
expects: expects{
message: syscall.EMFILE.Error(),
code: eaiSystem,
err: syscall.EMFILE,
},
}, {
name: "with C.EAI_NONAME",
args: args{
code: eaiNoName,
err: nil,
goos: "linux",
},
expects: expects{
message: ErrOODNSNoSuchHost.Error(),
code: eaiNoName,
err: ErrOODNSNoSuchHost,
},
}, {
name: "with C.EAI_NODATA on Linux",
args: args{
code: eaiNoData,
err: nil,
goos: "linux",
},
expects: expects{
message: ErrOODNSNoAnswer.Error(),
code: eaiNoData,
err: ErrOODNSNoAnswer,
},
}, {
name: "with C.EAI_NODATA on Android",
args: args{
code: eaiNoData,
err: nil,
goos: "android",
},
expects: expects{
message: ErrAndroidDNSCacheNoData.Error(),
code: eaiNoData,
err: ErrAndroidDNSCacheNoData,
},
}, {
name: "with an unhandled error",
args: args{
code: eaiBadFlags,
err: nil,
goos: "linux",
},
expects: expects{
message: ErrOODNSMisbehaving.Error(),
code: eaiBadFlags,
err: ErrOODNSMisbehaving,
},
}}
for _, input := range inputs {
t.Run(input.name, func(t *testing.T) {
state := newGetaddrinfoState(getaddrinfoNumSlots)
err := state.toError(input.args.code, input.args.err, input.args.goos)
if err == nil {
t.Fatal("expected non-nil error here")
}
if err.Error() != input.expects.message {
t.Fatal("unexpected error message")
}
var gaierr *ErrGetaddrinfo
if !errors.As(err, &gaierr) {
t.Fatal("cannot convert error to ErrGetaddrinfo")
}
if gaierr.Code != input.expects.code {
t.Fatal("unexpected code")
}
if !errors.Is(gaierr.Underlying, input.expects.err) {
t.Fatal("unexpected underlying error")
}
})
}
}