| 1 | package bot |
| 2 | |
| 3 | import ( |
| 4 | "bytes" |
| 5 | "encoding/json" |
| 6 | "fmt" |
| 7 | "net/http" |
| 8 | "net/url" |
| 9 | "strings" |
| 10 | "time" |
| 11 | |
| 12 | "lchat/internal/e2ee" |
| 13 | ) |
| 14 | |
| 15 | // Provision turns an admin agent-invite into a bot identity — agent/ |
| 16 | // provision.mjs (web/static/join.js run headlessly) in Go. The invite's |
| 17 | // #fragment secret T never reaches the server: we derive the invite id from |
| 18 | // it, generate our own keypair, claim a device token by presenting the derived |
| 19 | // claim secret, and register the public key in the roster. The screen name is |
| 20 | // never sent — an agent's label was set server-side when the invite was minted. |
| 21 | func Provision(base, fragment, name string) (*Session, error) { |
| 22 | base = strings.TrimRight(base, "/") |
| 23 | client := &http.Client{Timeout: 30 * time.Second} |
| 24 | |
| 25 | inv, err := e2ee.DeriveInvite(fragment) |
| 26 | if err != nil { |
| 27 | return nil, fmt.Errorf("bot: bad invite fragment: %w", err) |
| 28 | } |
| 29 | |
| 30 | var info struct { |
| 31 | OK bool `json:"ok"` |
| 32 | Wrapped string `json:"wrapped"` |
| 33 | } |
| 34 | if err := getJSON(client, base+"/api/key-invite/"+url.PathEscape(inv.ID), &info); err != nil { |
| 35 | return nil, err |
| 36 | } |
| 37 | if !info.OK { |
| 38 | return nil, fmt.Errorf("bot: invite is used or invalid — mint a fresh one") |
| 39 | } |
| 40 | if info.Wrapped != "" { |
| 41 | return nil, fmt.Errorf("bot: that's an add-device link; use a fresh-person agent invite") |
| 42 | } |
| 43 | |
| 44 | kp, err := e2ee.GenerateUserKeypair() |
| 45 | if err != nil { |
| 46 | return nil, err |
| 47 | } |
| 48 | |
| 49 | var claim struct { |
| 50 | OK bool `json:"ok"` |
| 51 | Token string `json:"token"` |
| 52 | } |
| 53 | err = postJSON(client, base+"/api/key-invite/"+url.PathEscape(inv.ID)+"/claim", |
| 54 | map[string]string{"claim_secret": inv.ClaimSecret}, &claim) |
| 55 | if err != nil { |
| 56 | return nil, err |
| 57 | } |
| 58 | if !claim.OK || claim.Token == "" { |
| 59 | return nil, fmt.Errorf("bot: couldn't claim the invite (it may have just been used)") |
| 60 | } |
| 61 | |
| 62 | err = postJSON(client, base+"/api/pubkey", |
| 63 | map[string]string{"token": claim.Token, "public_key": kp.PublicKey}, nil) |
| 64 | if err != nil { |
| 65 | return nil, err |
| 66 | } |
| 67 | |
| 68 | return &Session{Token: claim.Token, Name: name, UserPub: kp.PublicKey, UserPriv: kp.PrivateKey}, nil |
| 69 | } |
| 70 | |
| 71 | // EnsureSession loads the session at path, self-provisioning it first when |
| 72 | // the file is absent and an invite is available. This is what makes a freshly |
| 73 | // staged sidecar zero-touch (#806): add-bot — and the activator's co-spawn on |
| 74 | // a hibernating host — hand the process one-time invites in its environment, |
| 75 | // and the first boot redeems them and writes the session, so keys are born on |
| 76 | // the machine that runs the bot rather than copied to it. A missing session |
| 77 | // with no invite still returns (nil, nil): "not provisioned" stays a normal |
| 78 | // state the caller reports. |
| 79 | func EnsureSession(base, path, invite, name string, logf func(string, ...any)) (*Session, error) { |
| 80 | sess, err := LoadSession(path) |
| 81 | if err != nil || sess != nil { |
| 82 | return sess, err |
| 83 | } |
| 84 | invite = strings.TrimSpace(invite) |
| 85 | if invite == "" { |
| 86 | return nil, nil |
| 87 | } |
| 88 | if logf != nil { |
| 89 | logf("bot: no session at %s — provisioning %q from its invite", path, name) |
| 90 | } |
| 91 | sess, err = Provision(base, invite, name) |
| 92 | if err != nil { |
| 93 | return nil, fmt.Errorf("bot: provision %q: %w", name, err) |
| 94 | } |
| 95 | // Persist before connecting: the invite is one-time, so a session held |
| 96 | // only in memory would be unrecoverable after the next restart. |
| 97 | if err := sess.Save(path); err != nil { |
| 98 | return nil, fmt.Errorf("bot: save session %s: %w", path, err) |
| 99 | } |
| 100 | return sess, nil |
| 101 | } |
| 102 | |
| 103 | func getJSON(client *http.Client, url string, out any) error { |
| 104 | resp, err := client.Get(url) |
| 105 | if err != nil { |
| 106 | return err |
| 107 | } |
| 108 | defer resp.Body.Close() |
| 109 | return json.NewDecoder(resp.Body).Decode(out) |
| 110 | } |
| 111 | |
| 112 | func postJSON(client *http.Client, url string, body, out any) error { |
| 113 | raw, err := json.Marshal(body) |
| 114 | if err != nil { |
| 115 | return err |
| 116 | } |
| 117 | resp, err := client.Post(url, "application/json", bytes.NewReader(raw)) |
| 118 | if err != nil { |
| 119 | return err |
| 120 | } |
| 121 | defer resp.Body.Close() |
| 122 | if out == nil { |
| 123 | if resp.StatusCode != http.StatusOK { |
| 124 | return fmt.Errorf("bot: %s: HTTP %d", url, resp.StatusCode) |
| 125 | } |
| 126 | return nil |
| 127 | } |
| 128 | return json.NewDecoder(resp.Body).Decode(out) |
| 129 | } |
| 130 | |
amadan