Consdiff: use lengths on inputs so they don't need NUL at the end

This is part of #27244, so that we can safely mmap consensus
documents.

2 files changed, 14 insertions, 5 deletions

diff --git a/src/feature/dircache/consdiffmgr.c b/src/feature/dircache/consdiffmgr.c
index 304b64f3b6..7999df08d5 100644
--- a/src/feature/dircache/consdiffmgr.c
+++ b/src/feature/dircache/consdiffmgr.c
@@ -1496,7 +1496,10 @@ consensus_diff_worker_threadfn(void *state_, void *work_)
     // XXXX ugh; this is going to calculate the SHA3 of both its
     // XXXX inputs again, even though we already have that. Maybe it's time
     // XXXX to change the API here?
-    consensus_diff = consensus_diff_generate(diff_from_nt, diff_to_nt);
+    consensus_diff = consensus_diff_generate(diff_from_nt,
+                                             strlen(diff_from_nt),
+                                             diff_to_nt,
+                                             strlen(diff_to_nt));
     tor_free(diff_from_nt);
     tor_free(diff_to_nt);
   }
@@ -1746,8 +1749,8 @@ consensus_compress_worker_threadfn(void *state_, void *work_)
                           (const uint8_t *)consensus, bodylen);
   {
     const char *start, *end;
-    if (router_get_networkstatus_v3_signed_boundaries(consensus,
-                                                        &start, &end) < 0) {
+    if (router_get_networkstatus_v3_signed_boundaries(consensus, bodylen,
+                                                      &start, &end) < 0) {
       start = consensus;
       end = consensus+bodylen;
     }
diff --git a/src/feature/dircache/directory.c b/src/feature/dircache/directory.c
index de0bcdbfa7..8e5fc86836 100644
--- a/src/feature/dircache/directory.c
+++ b/src/feature/dircache/directory.c
@@ -2607,12 +2607,17 @@ handle_response_fetch_consensus(dir_connection_t *conn,
     /* First find our previous consensus. Maybe it's in ram, maybe not. */
     cached_dir_t *cd = dirserv_get_consensus(flavname);
     const char *consensus_body;
+    size_t consensus_body_len;
     char *owned_consensus = NULL;
     if (cd) {
       consensus_body = cd->dir;
+      consensus_body_len = cd->dir_len;
     } else {
       owned_consensus = networkstatus_read_cached_consensus(flavname);
-      consensus_body = owned_consensus;
+      if (owned_consensus) {
+        consensus_body = owned_consensus;
+        consensus_body_len = strlen(consensus_body);
+      }
     }
     if (!consensus_body) {
       log_warn(LD_DIR, "Received a consensus diff, but we can't find "
@@ -2622,7 +2627,8 @@ handle_response_fetch_consensus(dir_connection_t *conn,
       return -1;
     }
 
-    new_consensus = consensus_diff_apply(consensus_body, body);
+    new_consensus = consensus_diff_apply(consensus_body, consensus_body_len,
+                                         body, body_len);
     tor_free(owned_consensus);
     if (new_consensus == NULL) {
       log_warn(LD_DIR, "Could not apply consensus diff received from server "