refactor: move the transport onto the official Gitea SDK

The transport was hand-rolled net/http against the REST API. The payload shapes were ours, in internal/wire, which meant every field Gitea learned was a field somebody here had to notice; and "does this instance have issue dependencies?" had to be guessed from a status code, because a 404 from a missing route and a 404 from a missing issue look alike. The SDK settles both. The shapes are maintained by the people who maintain the server, and the client negotiates the server's version when it is built, so the dependency endpoint is now gated on `>= 1.20.0` — verified against the release where the route appears, not assumed. Below the gate nothing is requested at all. internal/wire keeps what the SDK has no answer for: addressing. The SDK takes an owner, a name and an int64 and never parses, while `42`, `#42`, `owner/repo#42` and an issue URL are four spellings of one address, all four are what somebody has in hand, and Key is what the ledger is keyed by. The payload structs go. Four things that had to survive the move, and did: - request bodies still land in .kettle/payload/, now via an http.RoundTripper on the client the SDK is given — which is better than before, because it files every request rather than the ones a call site remembered to name; - errors still carry the HTTP status AND the response body, and a decode failure on a 2xx is deliberately not an APIError, so the dependency probe cannot read a bad decode as "feature missing"; - the number -> slug ledger is untouched, entries still outlive the files they name; - Client.For(repo) still re-points at another repository for one call. What it cost, written down in AGENTS.md where it happened. internal/mapping's layering test was a fact about the import graph — nothing in its closure could open a socket — and the SDK ships its types and its client in one package, so the test now asserts what is still true: the bridge performs no I/O, checked on direct imports plus a grep for time.Now. A run makes one extra request before it does anything. Gitea's issue edit endpoint carries no labels, so a push whose labels changed needs a second call; push makes it and says so. go.mod requires go 1.26, which the SDK sets and which is now the floor for building this binary. internal/issue and internal/project are byte-identical. The domain did not notice, which is the whole argument for the layering. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-08-11 19:29:38 +05:00
parent 9480e48312
commit 1239fdee70
292 changed files with 51205 additions and 864 deletions
@@ -0,0 +1,184 @@
+package httpsig
+
+import (
+	"crypto"
+	"encoding/base64"
+	"errors"
+	"fmt"
+	"net/http"
+	"strconv"
+	"strings"
+	"time"
+)
+
+var _ Verifier = &verifier{}
+
+type verifier struct {
+	header      http.Header
+	kId         string
+	signature   string
+	created     int64
+	expires     int64
+	headers     []string
+	sigStringFn func(http.Header, []string, int64, int64) (string, error)
+}
+
+func newVerifier(h http.Header, sigStringFn func(http.Header, []string, int64, int64) (string, error)) (*verifier, error) {
+	scheme, s, err := getSignatureScheme(h)
+	if err != nil {
+		return nil, err
+	}
+	kId, sig, headers, created, expires, err := getSignatureComponents(scheme, s)
+	if created != 0 {
+		//check if created is not in the future, we assume a maximum clock offset of 10 seconds
+		now := time.Now().Unix()
+		if created-now > 10 {
+			return nil, errors.New("created is in the future")
+		}
+	}
+	if expires != 0 {
+		//check if expires is in the past, we assume a maximum clock offset of 10 seconds
+		now := time.Now().Unix()
+		if now-expires > 10 {
+			return nil, errors.New("signature expired")
+		}
+	}
+	if err != nil {
+		return nil, err
+	}
+	return &verifier{
+		header:      h,
+		kId:         kId,
+		signature:   sig,
+		created:     created,
+		expires:     expires,
+		headers:     headers,
+		sigStringFn: sigStringFn,
+	}, nil
+}
+
+func (v *verifier) KeyId() string {
+	return v.kId
+}
+
+func (v *verifier) Verify(pKey crypto.PublicKey, algo Algorithm) error {
+	s, err := signerFromString(string(algo))
+	if err == nil {
+		return v.asymmVerify(s, pKey)
+	}
+	m, err := macerFromString(string(algo))
+	if err == nil {
+		return v.macVerify(m, pKey)
+	}
+	return fmt.Errorf("no crypto implementation available for %q", algo)
+}
+
+func (v *verifier) macVerify(m macer, pKey crypto.PublicKey) error {
+	key, ok := pKey.([]byte)
+	if !ok {
+		return fmt.Errorf("public key for MAC verifying must be of type []byte")
+	}
+	signature, err := v.sigStringFn(v.header, v.headers, v.created, v.expires)
+	if err != nil {
+		return err
+	}
+	actualMAC, err := base64.StdEncoding.DecodeString(v.signature)
+	if err != nil {
+		return err
+	}
+	ok, err = m.Equal([]byte(signature), actualMAC, key)
+	if err != nil {
+		return err
+	} else if !ok {
+		return fmt.Errorf("invalid http signature")
+	}
+	return nil
+}
+
+func (v *verifier) asymmVerify(s signer, pKey crypto.PublicKey) error {
+	toHash, err := v.sigStringFn(v.header, v.headers, v.created, v.expires)
+	if err != nil {
+		return err
+	}
+	signature, err := base64.StdEncoding.DecodeString(v.signature)
+	if err != nil {
+		return err
+	}
+	err = s.Verify(pKey, []byte(toHash), signature)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func getSignatureScheme(h http.Header) (scheme SignatureScheme, val string, err error) {
+	s := h.Get(string(Signature))
+	sigHasAll := strings.Contains(s, keyIdParameter) ||
+		strings.Contains(s, headersParameter) ||
+		strings.Contains(s, signatureParameter)
+	a := h.Get(string(Authorization))
+	authHasAll := strings.Contains(a, keyIdParameter) ||
+		strings.Contains(a, headersParameter) ||
+		strings.Contains(a, signatureParameter)
+	if sigHasAll && authHasAll {
+		err = fmt.Errorf("both %q and %q have signature parameters", Signature, Authorization)
+		return
+	} else if !sigHasAll && !authHasAll {
+		err = fmt.Errorf("neither %q nor %q have signature parameters", Signature, Authorization)
+		return
+	} else if sigHasAll {
+		val = s
+		scheme = Signature
+		return
+	} else { // authHasAll
+		val = a
+		scheme = Authorization
+		return
+	}
+}
+
+func getSignatureComponents(scheme SignatureScheme, s string) (kId, sig string, headers []string, created int64, expires int64, err error) {
+	if as := scheme.authScheme(); len(as) > 0 {
+		s = strings.TrimPrefix(s, as+prefixSeparater)
+	}
+	params := strings.Split(s, parameterSeparater)
+	for _, p := range params {
+		kv := strings.SplitN(p, parameterKVSeparater, 2)
+		if len(kv) != 2 {
+			err = fmt.Errorf("malformed http signature parameter: %v", kv)
+			return
+		}
+		k := kv[0]
+		v := strings.Trim(kv[1], parameterValueDelimiter)
+		switch k {
+		case keyIdParameter:
+			kId = v
+		case createdKey:
+			created, err = strconv.ParseInt(v, 10, 64)
+			if err != nil {
+				return
+			}
+		case expiresKey:
+			expires, err = strconv.ParseInt(v, 10, 64)
+			if err != nil {
+				return
+			}
+		case algorithmParameter:
+			// Deprecated, ignore
+		case headersParameter:
+			headers = strings.Split(v, headerParameterValueDelim)
+		case signatureParameter:
+			sig = v
+		default:
+			// Ignore unrecognized parameters
+		}
+	}
+	if len(kId) == 0 {
+		err = fmt.Errorf("missing %q parameter in http signature", keyIdParameter)
+	} else if len(sig) == 0 {
+		err = fmt.Errorf("missing %q parameter in http signature", signatureParameter)
+	} else if len(headers) == 0 { // Optional
+		headers = defaultHeaders
+	}
+	return
+}