487 lines
20 KiB
Markdown
487 lines
20 KiB
Markdown
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# Chapter VI: Getting a webpage from an HTTP/HTTPS/HTTP3 endpoint.
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This chapter describes measuring getting a webpage from an
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HTTPS endpoint. We have seen how to TCP connect, we have
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seen how to TLS handshake, now it's time to see how we can
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combine these operations with fetching a webpage from a
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given TCP endpoint speaking HTTP and TLS. (As well as to
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provide you with information on how to otherwise fetch
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from HTTP and HTTP/3 endpoints.)
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The program we're going to write, `main.go`, will show a
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high-level operation to perform this measurement in a
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single API call. The code implementing this API call will
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combine the operations we have seen in previous chapter
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with the "give me the webpage" operation. We are still
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quite far away from the ability of "measuring a URL" but
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we are increasingly moving towards more complex operations.
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(This file is auto-generated. Do not edit it directly! To apply
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changes you need to modify `./internal/tutorial/measurex/chapter06/main.go`.)
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## main.go
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We have package declaration and imports as usual.
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```Go
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package main
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import (
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"context"
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"encoding/json"
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"flag"
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"fmt"
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"net/url"
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"time"
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"github.com/ooni/probe-cli/v3/internal/measurex"
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"github.com/ooni/probe-cli/v3/internal/runtimex"
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)
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```
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We have factored the three lines to print a measurement
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into the following utility function called `print`.
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```Go
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func print(v interface{}) {
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data, err := json.Marshal(v)
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runtimex.PanicOnError(err, "json.Marshal failed")
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fmt.Printf("%s\n", string(data))
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}
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```
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The initial part of the program is pretty much the same as the one
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used in previous chapters, expect that we have a few more command line
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flags now, so I will not add further comments.
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```Go
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func main() {
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sni := flag.String("sni", "dns.google", "value for SNI extension")
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address := flag.String("address", "8.8.4.4:443", "remote endpoint address")
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timeout := flag.Duration("timeout", 60*time.Second, "timeout to use")
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flag.Parse()
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ctx, cancel := context.WithTimeout(context.Background(), *timeout)
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defer cancel()
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mx := measurex.NewMeasurerWithDefaultSettings()
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```
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### HTTPEndpoint: a description of what to measure
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First of all, let us create a description of the endpoint
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for `measurex`. Up to this point we have used endpoint
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to describe a level-4-like address. Therefore, we have seen
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TCP endpoints being used for the TCP connect and the TLS
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handshake, and we have seen QUIC endpoints being used
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for the QUIC handshake. Now, however, we are going
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to need more information to characterize the endpoint.
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```Go
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epnt := &measurex.HTTPEndpoint{
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Domain: *sni,
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Network: "tcp",
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Address: *address,
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SNI: *sni,
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ALPN: []string{"h2", "http/1.1"},
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URL: &url.URL{
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Scheme: "https",
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Host: *sni,
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Path: "/",
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},
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Header: measurex.NewHTTPRequestHeaderForMeasuring(),
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}
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```
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In fact, in the above definition we recognize fields
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we have already discussed, such as:
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- `Network`, describing whether to use "tcp" or "quic";
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- `Address`, which is the endpoint address.
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But we also need to combine into this view of the
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endpoint additional fields for TLS:
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- `SNI`, to set the SNI;
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- `ALPN`, to set the ALPN;
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But then we also need to specify:
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- the URL to use;
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- the headers to use (for which we're using a handy
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factory for creating reasonable defaults for measuring).
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This API is not the highest level API with which to do
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the job, but it's still handy to introduce the
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`measurex.HTTPEndpoint` data structure since it's
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used by higher level APIs.
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(You may also be wondering about the CA pool. It turns
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out that for APIs such as this one and for higher
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level APIs, the default is to always use the bundled
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Mozilla CA pool, because this is what we use in
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most cases for performing measurements.)
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### HTTPEndpointGetWithoutCookies
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When used with an HTTP URL, the `HTTPEndpointGetWithoutCookies`
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method combines two operations:
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- TCP connect
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- HTTP GET
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When the URL is HTTPS, we do:
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- TCP connect
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- TLS handshake
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- HTTP GET (or HTTP/2 GET depending on the ALPN)
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When the `HTTPEndpoint.Network` field value
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is QUIC, instead we do:
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- QUIC handshake
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- HTTP/3 GET
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```Go
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m := mx.HTTPEndpointGetWithoutCookies(ctx, epnt)
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```
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The arguments for `HTTPEndpointGetWithDBWithoutCookies` are:
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- the context for deadline/timeout
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- the HTTPEndpoint descriptor
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The result is an `HTTPEndpointMeasurement` which
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you can inspect with
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```
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go doc ./internal/measurex.HTTPEndpointMeasurement
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```
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### Printing the measurement
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Let us now print the resulting measurement.
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```Go
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print(m)
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}
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```
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## Running the example program
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Let us perform a vanilla run first:
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```bash
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go run -race ./internal/tutorial/measurex/chapter06
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```
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This is the JSON output. Let us comment it in detail:
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```Javascript
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{
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// The returned type is called HTTPEndpointMeasurement
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// and you see that here on top we indeed have the
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// information on the endpoint and the URL.
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"url": "https://dns.google/",
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"network": "tcp",
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"address": "8.8.4.4:443",
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// Internally, HTTPEndpointGetWithoutCookies calls
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// TCPConnect and here we see the corresponding event
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"connect": [
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{
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"address": "8.8.4.4:443",
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"failure": null,
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"operation": "connect",
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"proto": "tcp",
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"t": 0.02422375,
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"started": 0.002269291,
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"oddity": ""
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}
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],
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// These are the I/O operations we have already seen
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// in previous chapters
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"read_write": [
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{
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"address": "8.8.4.4:443",
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"failure": null,
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"num_bytes": 280,
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"operation": "write",
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"proto": "tcp",
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"t": 0.024931791,
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"started": 0.024910416,
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"oddity": ""
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},
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{
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"address": "8.8.4.4:443",
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"failure": null,
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"num_bytes": 517,
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"operation": "read",
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"proto": "tcp",
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"t": 0.063629791,
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"started": 0.024935666,
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"oddity": ""
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},
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{
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"address": "8.8.4.4:443",
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"failure": null,
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"num_bytes": 4301,
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"operation": "read",
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"proto": "tcp",
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"t": 0.064183,
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"started": 0.064144208,
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"oddity": ""
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},
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{
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"address": "8.8.4.4:443",
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"failure": null,
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"num_bytes": 64,
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"operation": "write",
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"proto": "tcp",
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"t": 0.065464041,
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"started": 0.065441333,
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"oddity": ""
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},
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{
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"address": "8.8.4.4:443",
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"failure": null,
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"num_bytes": 86,
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"operation": "write",
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"proto": "tcp",
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"t": 0.067256083,
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"started": 0.067224375,
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"oddity": ""
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},
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{
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"address": "8.8.4.4:443",
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"failure": null,
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"num_bytes": 201,
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"operation": "write",
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"proto": "tcp",
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"t": 0.067674416,
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"started": 0.067652375,
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"oddity": ""
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},
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{
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"address": "8.8.4.4:443",
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"failure": null,
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"num_bytes": 93,
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"operation": "read",
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"proto": "tcp",
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"t": 0.086618708,
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"started": 0.067599208,
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"oddity": ""
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},
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{
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"address": "8.8.4.4:443",
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"failure": null,
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"num_bytes": 31,
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"operation": "write",
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"proto": "tcp",
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"t": 0.086703625,
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"started": 0.0866745,
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"oddity": ""
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},
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{
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"address": "8.8.4.4:443",
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"failure": null,
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"num_bytes": 2028,
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"operation": "read",
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"proto": "tcp",
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"t": 0.337785916,
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"started": 0.086717333,
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"oddity": ""
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},
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{
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"address": "8.8.4.4:443",
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"failure": null,
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"num_bytes": 39,
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"operation": "write",
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"proto": "tcp",
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"t": 0.338514916,
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"started": 0.338485375,
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"oddity": ""
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},
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{
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"address": "8.8.4.4:443",
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"failure": null,
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"num_bytes": 24,
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"operation": "write",
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"proto": "tcp",
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"t": 0.338800833,
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"started": 0.338788625,
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"oddity": ""
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},
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{
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"address": "8.8.4.4:443",
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"failure": "connection_already_closed",
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"operation": "read",
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"proto": "tcp",
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"t": 0.338888041,
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"started": 0.338523291,
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"oddity": ""
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}
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],
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// Internally, HTTPEndpointGetWithoutCookies calls TLSConnectAndHandshake,
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// and here's the resulting handshake event. Of course, if we
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// specified a QUIC endpoint we would instead see here a
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// QUIC handshake event. And, we would not see any handshake
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// if the URL was instead an HTTP URL.
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"tls_handshake": [
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{
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"cipher_suite": "TLS_AES_128_GCM_SHA256",
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"failure": null,
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"negotiated_proto": "h2",
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"tls_version": "TLSv1.3",
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"peer_certificates": [
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{
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|
|
"data": "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",
|
||
|
|
"format": "base64"
|
||
|
|
},
|
||
|
|
{
|
||
|
|
"data": "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",
|
||
|
|
"format": "base64"
|
||
|
|
},
|
||
|
|
{
|
||
|
|
"data": "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",
|
||
|
|
"format": "base64"
|
||
|
|
}
|
||
|
|
],
|
||
|
|
"t": 0.065514708,
|
||
|
|
"address": "8.8.4.4:443",
|
||
|
|
"server_name": "dns.google",
|
||
|
|
"alpn": [
|
||
|
|
"h2",
|
||
|
|
"http/1.1"
|
||
|
|
],
|
||
|
|
"no_tls_verify": false,
|
||
|
|
"oddity": "",
|
||
|
|
"proto": "tcp",
|
||
|
|
"started": 0.024404083
|
||
|
|
}
|
||
|
|
],
|
||
|
|
|
||
|
|
// Finally here we see information about the round trip, which
|
||
|
|
// is formatted according the df-001-httpt data format:
|
||
|
|
"http_round_trip": [
|
||
|
|
{
|
||
|
|
|
||
|
|
// This field indicates whether there was an error during
|
||
|
|
// the HTTP round trip:
|
||
|
|
"failure": null,
|
||
|
|
|
||
|
|
// This field contains the request method, URL, and HTTP headers
|
||
|
|
"request": {
|
||
|
|
"method": "GET",
|
||
|
|
"url": "https://dns.google/",
|
||
|
|
"headers": {
|
||
|
|
"accept": "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8",
|
||
|
|
"accept-language": "en-US;q=0.8,en;q=0.5",
|
||
|
|
"user-agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/90.0.4430.93 Safari/537.36"
|
||
|
|
}
|
||
|
|
},
|
||
|
|
|
||
|
|
// This field contains the response status code, body,
|
||
|
|
// and headers.
|
||
|
|
"response": {
|
||
|
|
"code": 200,
|
||
|
|
"headers": {
|
||
|
|
"accept-ranges": "none",
|
||
|
|
"alt-svc": "h3=\":443\"; ma=2592000,h3-29=\":443\"; ma=2592000,h3-T051=\":443\"; ma=2592000,h3-Q050=\":443\"; ma=2592000,h3-Q046=\":443\"; ma=2592000,h3-Q043=\":443\"; ma=2592000,quic=\":443\"; ma=2592000; v=\"46,43\"",
|
||
|
|
"cache-control": "private",
|
||
|
|
"content-security-policy": "object-src 'none';base-uri 'self';script-src 'nonce-bSLcJjaotppZl3Y2moIaxg==' 'strict-dynamic' 'report-sample' 'unsafe-eval' 'unsafe-inline' https: http:;report-uri https://csp.withgoogle.com/csp/honest_dns/1_0;frame-ancestors 'none'",
|
||
|
|
"content-type": "text/html; charset=UTF-8",
|
||
|
|
"date": "Fri, 24 Sep 2021 08:51:01 GMT",
|
||
|
|
"server": "scaffolding on HTTPServer2",
|
||
|
|
"strict-transport-security": "max-age=31536000; includeSubDomains; preload",
|
||
|
|
"vary": "Accept-Encoding",
|
||
|
|
"x-content-type-options": "nosniff",
|
||
|
|
"x-frame-options": "SAMEORIGIN",
|
||
|
|
"x-xss-protection": "0"
|
||
|
|
},
|
||
|
|
|
||
|
|
// The body in particular is a snapshot of the response
|
||
|
|
// body: we don't want to read and submit to the OONI
|
||
|
|
// collector large bodies.
|
||
|
|
"body": {
|
||
|
|
"data": "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",
|
||
|
|
"format": "base64"
|
||
|
|
},
|
||
|
|
|
||
|
|
// This field tells us whether the size of the read
|
||
|
|
// snapshot was smaller than the snapshot size. If
|
||
|
|
// not, then the body has been truncated.
|
||
|
|
"body_is_truncated": false,
|
||
|
|
|
||
|
|
// These extra fields are not part of the spec and
|
||
|
|
// hence we prefix them with `x_`. They tell us
|
||
|
|
// the length of the body and whether the content
|
||
|
|
// of the body is valid UTF8.
|
||
|
|
"x_body_length": 1383,
|
||
|
|
"x_body_is_utf8": true
|
||
|
|
},
|
||
|
|
|
||
|
|
// The t field is the moment where we finished the
|
||
|
|
// round trip and saved the event. The started field
|
||
|
|
// is instead when we started the round trip.
|
||
|
|
|
||
|
|
// You may notice that the start of the round trip
|
||
|
|
// if after the `t` of the handshake. This tells us
|
||
|
|
// that the code first connects, then handshakes, and
|
||
|
|
// finally creates HTTP code for performing the
|
||
|
|
// round trip.
|
||
|
|
"t": 0.338674625,
|
||
|
|
"started": 0.065926625,
|
||
|
|
|
||
|
|
// As usual we also compute an oddity value related
|
||
|
|
// in this case to the HTTP round trip.
|
||
|
|
"oddity": ""
|
||
|
|
}
|
||
|
|
]
|
||
|
|
}
|
||
|
|
```
|
||
|
|
|
||
|
|
Here are some suggestions for follow up measurements:
|
||
|
|
|
||
|
|
1. provoke a connect error by using:
|
||
|
|
|
||
|
|
```
|
||
|
|
go run -race ./internal/tutorial/measurex/chapter06 -address 127.0.0.1:1
|
||
|
|
```
|
||
|
|
|
||
|
|
2. provoke a TLS handshake error by using:
|
||
|
|
|
||
|
|
```
|
||
|
|
go run -race ./internal/tutorial/measurex/chapter06 -sni example.com
|
||
|
|
```
|
||
|
|
|
||
|
|
3. provoke an HTTP round trip error by using:
|
||
|
|
|
||
|
|
```
|
||
|
|
go run -race ./internal/tutorial/measurex/chapter06 -address 8.8.8.8:853
|
||
|
|
```
|
||
|
|
|
||
|
|
4. modify the code to fetch an HTTP endpoint instead (hint: you
|
||
|
|
need to change the HTTPEndpoint's URL scheme);
|
||
|
|
|
||
|
|
5. modify the code to use QUIC and HTTP/3 instead (hint: you need to
|
||
|
|
change the HTTPEndpoint's network and... is this enough?).
|
||
|
|
|
||
|
|
## Conclusion
|
||
|
|
|
||
|
|
We have seen how to measure the flow of fetching a
|
||
|
|
specific webpage from an HTTPEndpoint.
|
||
|
|
|