feat: msa authentication

1 files changed, 90 insertions, 1 deletions

diff --git a/mcsh.sh b/mcsh.sh
index d3e57cb..5a41cbb 100755
--- a/mcsh.sh
+++ b/mcsh.sh
@@ -8,6 +8,92 @@ NATIVES_DIR="natives"
 ASSETS_DIR="assets"
 GAME_DIR="run"
 
+function auth (   
+    CLIENT_ID="9e97542c-b7d5-4a02-a656-4559dad4590a"
+    DEVICE_CODE_URL="https://login.microsoftonline.com/consumers/oauth2/v2.0/devicecode"
+    TOKEN_URL="https://login.microsoftonline.com/consumers/oauth2/v2.0/token"
+    XBL_AUTH_URL="https://user.auth.xboxlive.com/user/authenticate"
+    XSTS_TOKEN_URL="https://xsts.auth.xboxlive.com/xsts/authorize"
+    MC_AUTH_URL="https://api.minecraftservices.com/authentication/login_with_xbox"
+
+    function login (
+        printf 'getting device code\n' >&2
+        res="$(curl -s -X POST "$DEVICE_CODE_URL" -H 'Content-Type: application/x-www-form-urlencoded' -d "client_id=$CLIENT_ID&scope=XboxLive.signin%20offline_access")"
+        device_code="$(<<<"$res" jq -r '.device_code')"
+        message="$(<<<"$res" jq -r '.message')"
+
+        printf '%s\n' "$message" >&2
+
+        printf 'waiting for token...\n' >&2
+        pending=true
+        while [[ "$pending" == true ]]; do
+            res="$(curl -s -X POST "$TOKEN_URL" -H 'Content-Type: application/x-www-form-urlencoded' -d "grant_type=urn:ietf:params:oauth:grant-type:device_code&client_id=$CLIENT_ID&device_code=$device_code")"
+            pending="$(<<<"$res" jq -r '.error == "authorization_pending"')"
+            sleep 1
+        done
+
+        printf '%s\n' "$res"
+    )
+
+    if [[ -z "$(jq -r '.refresh_token // ""' auth.json)" ]]; then
+        printf 'logging in\n' >&2
+        res="$(login)"
+    else
+        printf 'refreshing msa auth\n' >&2
+        refresh_token="$(jq -r '.refresh_token' auth.json)"
+        res="$(curl -s -X POST "$TOKEN_URL" -H 'Content-Type: application/x-www-form-urlencoded' -d "grant_type=refresh_token&client_id=$CLIENT_ID&refresh_token=$refresh_token")"
+    fi
+
+    refresh_token="$(<<<"$res" jq -r '.refresh_token')"
+    msa_token="$(<<<"$res" jq -r '.access_token')"
+
+    auth="$(jq --arg token "$refresh_token" '. + {"refresh_token": $token}' auth.json)"
+    <<<"$auth" cat > auth.json
+
+    printf 'authenticating with xbox live\n' >&2
+    req="$(jq -n --arg token "$msa_token" '{"Properties": {"AuthMethod": "RPS", "SiteName": "user.auth.xboxlive.com", "RpsTicket": "d=\($token)"}, "RelyingParty": "http://auth.xboxlive.com", "TokenType": "JWT"}')"
+    res="$(curl -s -X POST "$XBL_AUTH_URL" -H 'Content-Type: application/json' -H 'Accept: application/json' -d "$req")"
+    xuid="$(<<<"$res" jq -r '.DisplayClaims.xui[0].uhs')"
+    xbl_token="$(<<<"$res" jq -r '.Token')"
+
+    # not 100% sure this is *actually* the xuid, but the game doesnt seem to
+    # care, even if passed a nonsense value
+    auth="$(jq --arg xuid "$xuid" '. + {"xuid": $xuid}' auth.json)"
+    <<<"$auth" cat > auth.json
+
+    printf 'getting xsts token\n' >&2
+    req="$(jq -n --arg token "$xbl_token" '{"Properties": {"SandboxId": "RETAIL", "UserTokens": [ $token ]}, "RelyingParty": "rp://api.minecraftservices.com/", "TokenType": "JWT"}')"
+    res="$(curl -s -X POST "$XSTS_TOKEN_URL" -H 'Content-Type: application/json' -H 'Accept: application/json' -d "$req")"
+    xsts_token="$(<<<"$res" jq -r '.Token')"
+
+    printf 'authenticating with mincraft\n' >&2
+    req="$(jq -n --arg xuid "$xuid" --arg token "$xsts_token" '{"identityToken": "XBL3.0 x=\($xuid);\($token)"}')"
+    res="$(curl -s -X POST "$MC_AUTH_URL" -H 'Content-Type: application/json' -H 'Accept: application/json' -d "$req")"
+    mc_token="$(<<<"$res" jq -r '.access_token')"
+
+    auth="$(jq --arg token "$mc_token" '. + {"access_token": $token}' auth.json)"
+    <<<"$auth" cat > auth.json
+
+    printf '%s\n' "$mc_token"
+)
+
+function update_profile (
+    MC_PROFILE_URL="https://api.minecraftservices.com/minecraft/profile"
+
+    token="$1"
+
+    printf 'getting minecraft profile\n' >&2
+    res="$(curl -s -X GET "$MC_PROFILE_URL" -H "Authorization: Bearer $token")"
+    if [[ -n "$(<<<"$res" jq -r '.error // ""')" ]]; then
+        printf 'error: user does not own minecraft\n' >&2
+        exit 1
+    fi
+    
+    #TODO: hyphenate uuid, for :sparkles: style :sparkles:
+    auth="$(<<<"$res" jq --slurpfile auth auth.json '$auth[0] + {"player_name": .name, "uuid": .id}')"
+    <<<"$auth" cat > auth.json
+)
+
 function update_metadata (
     printf 'updating version manifest\n' >&2
     mkdir -p "$VERSIONS_DIR"
@@ -29,6 +115,9 @@ function update_metadata (
 )
 
 function launch (
+    update_profile "$(auth)"
+    printf '\n' >&2
+
     meta="$(update_metadata "${1:-}")"
 
     export LIBRARIES_DIR
@@ -81,7 +170,7 @@ function launch (
             -e "s/\${launcher_version}/v0.1.0/g"
     }
 
-    printf 'starting game :3\n' >&2
+    printf '\nstarting game :3\n\n' >&2
     <<<"$meta" jq -r '.args.jvm + [.main_class] + .args.game | join(" ")' | replace_placeholders | xargs java
 )