hs-v3: Return descriptor decoding status when storing as client

This will allow us to callback into the HS subsytem depending on the decoding
status and return an extended SOCKS5 error code depending on the decoding
issue.

This is how we'll be able to tell the SocksPort connection if we are missing
or have bad client authorization for a service.

Part of #30382

Signed-off-by: David Goulet <dgoulet@torproject.org>

1 files changed, 27 insertions, 7 deletions

diff --git a/src/feature/hs/hs_cache.c b/src/feature/hs/hs_cache.c
index 39c2267462..59b05d8f0a 100644
--- a/src/feature/hs/hs_cache.c
+++ b/src/feature/hs/hs_cache.c
@@ -395,7 +395,8 @@ lookup_v3_desc_as_client(const uint8_t *key)
  * hs_cache_client_descriptor_t object. In case of error, return NULL. */
 static hs_cache_client_descriptor_t *
 cache_client_desc_new(const char *desc_str,
-                      const ed25519_public_key_t *service_identity_pk)
+                      const ed25519_public_key_t *service_identity_pk,
+                      hs_desc_decode_status_t *decode_status_out)
 {
   hs_desc_decode_status_t ret;
   hs_descriptor_t *desc = NULL;
@@ -435,6 +436,9 @@ cache_client_desc_new(const char *desc_str,
   client_desc->encoded_desc = tor_strdup(desc_str);
 
  end:
+  if (decode_status_out) {
+    *decode_status_out = ret;
+  }
   return client_desc;
 }
 
@@ -796,19 +800,34 @@ hs_cache_lookup_as_client(const ed25519_public_key_t *key)
   return NULL;
 }
 
-/** Public API: Given an encoded descriptor, store it in the client HS
- *  cache. Return -1 on error, 0 on success .*/
-int
+/** Public API: Given an encoded descriptor, store it in the client HS cache.
+ *  Return a decode status which changes how we handle the SOCKS connection
+ *  depending on its value:
+ *
+ *  HS_DESC_DECODE_OK: Returned on success. Descriptor was properly decoded
+ *                     and is now stored.
+ *
+ *  HS_DESC_DECODE_NEED_CLIENT_AUTH: Client authorization is needed but the
+ *                                   descriptor was still stored.
+ *
+ *  HS_DESC_DECODE_BAD_CLIENT_AUTH: Client authorization for this descriptor
+ *                                  was not usable but the descriptor was
+ *                                  still stored.
+ *
+ *  Any other codes means indicate where the error occured and the descriptor
+ *  was not stored. */
+hs_desc_decode_status_t
 hs_cache_store_as_client(const char *desc_str,
                          const ed25519_public_key_t *identity_pk)
 {
+  hs_desc_decode_status_t ret;
   hs_cache_client_descriptor_t *client_desc = NULL;
 
   tor_assert(desc_str);
   tor_assert(identity_pk);
 
   /* Create client cache descriptor object */
-  client_desc = cache_client_desc_new(desc_str, identity_pk);
+  client_desc = cache_client_desc_new(desc_str, identity_pk, &ret);
   if (!client_desc) {
     log_warn(LD_GENERAL, "HSDesc parsing failed!");
     log_debug(LD_GENERAL, "Failed to parse HSDesc: %s.", escaped(desc_str));
@@ -817,14 +836,15 @@ hs_cache_store_as_client(const char *desc_str,
 
   /* Push it to the cache */
   if (cache_store_as_client(client_desc) < 0) {
+    ret = HS_DESC_DECODE_GENERIC_ERROR;
     goto err;
   }
 
-  return 0;
+  return ret;
 
  err:
   cache_client_desc_free(client_desc);
-  return -1;
+  return ret;
 }
 
 /** Clean all client caches using the current time now. */