Merge remote-tracking branch 'teor/bug22502' into maint-0.3.1

3 files changed, 74 insertions, 23 deletions

diff --git a/src/common/compress.c b/src/common/compress.c
index 6513029f9c..e65894d9d2 100644
--- a/src/common/compress.c
+++ b/src/common/compress.c
@@ -102,8 +102,13 @@ tor_compress_impl(int compress,
 
   stream = tor_compress_new(compress, method, compression_level);
 
-  if (stream == NULL)
+  if (stream == NULL) {
+    log_warn(LD_GENERAL, "NULL stream while %scompressing",
+             compress?"":"de");
+    log_debug(LD_GENERAL, "method: %d level: %d at len: %zd",
+              method, compression_level, in_len);
     return -1;
+  }
 
   size_t in_len_orig = in_len;
   size_t out_remaining, out_alloc;
@@ -128,13 +133,32 @@ tor_compress_impl(int compress,
           // inputs.
           tor_compress_free(stream);
           stream = tor_compress_new(compress, method, compression_level);
+          if (stream == NULL) {
+            log_warn(LD_GENERAL, "NULL stream while %scompressing",
+                     compress?"":"de");
+            goto err;
+          }
         }
         break;
       case TOR_COMPRESS_OK:
         if (compress || complete_only) {
+          log_fn(protocol_warn_level, LD_PROTOCOL,
+                 "Unexpected %s while %scompressing",
+                 complete_only?"end of input":"result",
+                 compress?"":"de");
+          log_debug(LD_GENERAL, "method: %d level: %d at len: %zd",
+                    method, compression_level, in_len);
           goto err;
         } else {
-          goto done;
+          if (in_len != 0) {
+            log_fn(protocol_warn_level, LD_PROTOCOL,
+                   "Unexpected extra input while decompressing");
+            log_debug(LD_GENERAL, "method: %d level: %d at len: %zd",
+                      method, compression_level, in_len);
+            goto err;
+          } else {
+            goto done;
+          }
         }
         break;
       case TOR_COMPRESS_BUFFER_FULL: {
diff --git a/src/common/compress_zstd.c b/src/common/compress_zstd.c
index 99d05c37bd..a136db48bf 100644
--- a/src/common/compress_zstd.c
+++ b/src/common/compress_zstd.c
@@ -312,6 +312,8 @@ tor_zstd_compress_process(tor_zstd_compress_state_t *state,
       return TOR_COMPRESS_ERROR;
     }
 
+    // ZSTD_flushStream returns 0 if the frame is done, or >0 if it
+    // is incomplete.
     if (retval > 0)
       return TOR_COMPRESS_BUFFER_FULL;
   }
@@ -319,7 +321,7 @@ tor_zstd_compress_process(tor_zstd_compress_state_t *state,
   if (!finish) {
     // We're not done with the input, so no need to flush.
     return TOR_COMPRESS_OK;
-  } else if (state->compress && finish) {
+  } else if (state->compress) {
     retval = ZSTD_endStream(state->u.compress_stream, &output);
 
     *out = (char *)output.dst + output.pos;
@@ -338,10 +340,20 @@ tor_zstd_compress_process(tor_zstd_compress_state_t *state,
       return TOR_COMPRESS_BUFFER_FULL;
 
     return TOR_COMPRESS_DONE;
-  } else {
-    // ZSTD_flushStream returns 0 if the frame is done, or >0 if it
+  } else /* if (!state->compress) */ {
+    // ZSTD_decompressStream returns 0 if the frame is done, or >0 if it
     // is incomplete.
-    return (retval == 0) ? TOR_COMPRESS_DONE : TOR_COMPRESS_OK;
+    // We check this above.
+    tor_assert_nonfatal(!ZSTD_isError(retval));
+    // Start a new frame if this frame is done
+    if (retval == 0)
+      return TOR_COMPRESS_DONE;
+    // Don't check out_len, it might have some space left if the next output
+    // chunk is larger than the remaining space
+    else if (*in_len > 0)
+      return  TOR_COMPRESS_BUFFER_FULL;
+    else
+      return TOR_COMPRESS_OK;
   }
 
 #else // HAVE_ZSTD.
diff --git a/src/or/directory.c b/src/or/directory.c
index acd694ffee..ecd98119fe 100644
--- a/src/or/directory.c
+++ b/src/or/directory.c
@@ -2327,30 +2327,40 @@ connection_dir_client_reached_eof(dir_connection_t *conn)
 
   plausible = body_is_plausible(body, body_len, conn->base_.purpose);
   if (compression != NO_METHOD || !plausible) {
+    int severity = LOG_DEBUG;
     char *new_body = NULL;
     size_t new_len = 0;
+    const char *description1, *description2;
+    int want_to_try_both = 0;
+    int tried_both = 0;
     compress_method_t guessed = detect_compression_method(body, body_len);
-    if (compression == UNKNOWN_METHOD || guessed != compression) {
-      /* Tell the user if we don't believe what we're told about compression.*/
-      const char *description1, *description2;
 
-      description1 = compression_method_get_human_name(compression);
+    description1 = compression_method_get_human_name(compression);
 
-      if (BUG(description1 == NULL))
-        description1 = compression_method_get_human_name(UNKNOWN_METHOD);
+    if (BUG(description1 == NULL))
+      description1 = compression_method_get_human_name(UNKNOWN_METHOD);
 
-      if (guessed == UNKNOWN_METHOD && !plausible)
-        description2 = "confusing binary junk";
-      else
-        description2 = compression_method_get_human_name(guessed);
+    if (guessed == UNKNOWN_METHOD && !plausible)
+      description2 = "confusing binary junk";
+    else
+      description2 = compression_method_get_human_name(guessed);
 
-      log_info(LD_HTTP, "HTTP body from server '%s:%d' was labeled as %s, "
-               "but it seems to be %s.%s",
-               conn->base_.address, conn->base_.port, description1,
-               description2,
-               (compression>0 && guessed>0)?"  Trying both.":"");
+    /* Tell the user if we don't believe what we're told about compression.*/
+    want_to_try_both = (compression == UNKNOWN_METHOD ||
+                        guessed != compression);
+    if (want_to_try_both) {
+      severity = LOG_INFO;
     }
 
+    tor_log(severity, LD_HTTP,
+            "HTTP body from server '%s:%d' was labeled as %s, "
+            "%s it seems to be %s.%s",
+            conn->base_.address, conn->base_.port, description1,
+            guessed != compression?"but":"and",
+            description2,
+            (compression>0 && guessed>0 && want_to_try_both)?
+            "  Trying both.":"");
+
     /* Try declared compression first if we can.
      * tor_compress_supports_method() also returns true for NO_METHOD.
      * Ensure that the server is not sending us data compressed using a
@@ -2376,14 +2386,19 @@ connection_dir_client_reached_eof(dir_connection_t *conn)
     }
 
     if (!new_body && tor_compress_supports_method(guessed) &&
-        compression != guessed)
+        compression != guessed) {
       tor_uncompress(&new_body, &new_len, body, body_len, guessed,
                      !allow_partial, LOG_PROTOCOL_WARN);
+      tried_both = 1;
+    }
     /* If we're pretty sure that we have a compressed directory, and
      * we didn't manage to uncompress it, then warn and bail. */
     if (!plausible && !new_body) {
       log_fn(LOG_PROTOCOL_WARN, LD_HTTP,
-             "Unable to decompress HTTP body (server '%s:%d').",
+             "Unable to decompress HTTP body (tried %s%s%s, server '%s:%d').",
+             description1,
+             tried_both?" and ":"",
+             tried_both?description2:"",
              conn->base_.address, conn->base_.port);
       rv = -1;
       goto done;