hs: Fix the intro circuit max retry

Some parentheses were missing making the rend_max_intro_circs_per_period()
return a lower value than it was suppose to.

The calculation is that a service at most will open a number of intro points
that it wants which is 3 by default or HiddenServiceNumIntroductionPoints. Two
extra are launched for performance reason. Finally, this can happen twice for
two descriptors for the current and next time period.

From:
  2 * n_intro_wanted + 2

...which resulted in 8 for 3 intro points, this commit fixes it to:

  (n_intro_wanted + 2) * 2

... resulting in 12 possible intro point circuit which is the correct maximum
intro circuit allowed per period.

Last, this commit rate limits the the log message if we ever go above that
limit else over a INTRO_CIRC_RETRY_PERIOD, we can print it often!

Fixes #22159

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

1 files changed, 7 insertions, 0 deletions

diff --git a/changes/bug22159 b/changes/bug22159
new file mode 100644
index 0000000000..c319c7e322
--- /dev/null
+++ b/changes/bug22159
@@ -0,0 +1,7 @@
+  o Minor bugfixes (hidden service):
+    - A service is allowed to open a maximum number of circuits for a specific
+      period of time. That value was lower than it should be (8 vs 12) in the
+      normal case of 3 introduction points. Fixes bug 22159.; bugfix on
+      tor-0.3.0.5-rc.
+    - Rate limit the log if we ever go above the maximum number of allowed
+      intro circuits. Fixes bug 22159.; bugfix on tor-0.3.1.1-alpha.