Files
eth_hedge_sim/backend/app/api/auth.py
T

92 lines
2.9 KiB
Python

"""简单 HMAC Token 鉴权(无 JWT 依赖)。"""
from __future__ import annotations
import base64
import hashlib
import hmac
import json
import time
from typing import Annotated
from fastapi import Depends, HTTPException, status
from fastapi.security import HTTPAuthorizationCredentials, HTTPBearer
from pydantic import BaseModel, Field
from ..config import Settings, get_settings
_bearer = HTTPBearer(auto_error=False)
class LoginRequest(BaseModel):
username: str = Field(min_length=1)
password: str = Field(min_length=1)
class LoginResponse(BaseModel):
token: str
username: str
expires_in: int
env_name: str
mode: str
def _b64url(data: bytes) -> str:
return base64.urlsafe_b64encode(data).decode("ascii").rstrip("=")
def _b64url_decode(s: str) -> bytes:
pad = "=" * (-len(s) % 4)
return base64.urlsafe_b64decode(s + pad)
def issue_token(username: str, settings: Settings) -> tuple[str, int]:
exp = int(time.time()) + int(settings.auth_token_ttl_sec)
payload = {
"u": username,
"exp": exp,
"v": int(settings.auth_token_version),
}
raw = _b64url(json.dumps(payload, separators=(",", ":")).encode("utf-8"))
sig = hmac.new(
settings.auth_secret.encode("utf-8"),
raw.encode("ascii"),
hashlib.sha256,
).hexdigest()
return f"{raw}.{sig}", settings.auth_token_ttl_sec
def verify_token(token: str, settings: Settings) -> str:
try:
raw, sig = token.rsplit(".", 1)
except ValueError as e:
raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED, detail="invalid token") from e
expect = hmac.new(
settings.auth_secret.encode("utf-8"),
raw.encode("ascii"),
hashlib.sha256,
).hexdigest()
if not hmac.compare_digest(expect, sig):
raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED, detail="invalid token")
try:
payload = json.loads(_b64url_decode(raw))
except Exception as e:
raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED, detail="invalid token") from e
if int(payload.get("exp") or 0) < int(time.time()):
raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED, detail="token expired")
if int(payload.get("v") or 0) != int(settings.auth_token_version):
raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED, detail="token revoked")
username = str(payload.get("u") or "")
if not username:
raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED, detail="invalid token")
return username
def require_user(
creds: Annotated[HTTPAuthorizationCredentials | None, Depends(_bearer)],
settings: Annotated[Settings, Depends(get_settings)],
) -> str:
if creds is None or not creds.credentials:
raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED, detail="login required")
return verify_token(creds.credentials, settings)