[exim-cvs] Fix ${srs_encode ..} for mod-1024 day zero

Gitweb: https://git.exim.org/exim.git/commitdiff/51f9c07cd341c9c1a09b3816df988c6f44477c99

Commit:     51f9c07cd341c9c1a09b3816df988c6f44477c99
Parent:     12e1cfcb1649e2ea213c2965adf8479f1cff06f7
Author:     Jeremy Harris <jgh146exb@???>
AuthorDate: Tue Apr 11 11:59:08 2023 +0100
Committer:  Jeremy Harris <jgh146exb@???>
CommitDate: Tue Apr 11 11:59:08 2023 +0100

    Fix ${srs_encode ..} for mod-1024 day zero
---
 doc/doc-txt/ChangeLog |  3 +++
 src/src/expand.c      | 10 ++++------
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/doc/doc-txt/ChangeLog b/doc/doc-txt/ChangeLog
index 16d2b8ef8..d29ba6f65 100644
--- a/doc/doc-txt/ChangeLog
+++ b/doc/doc-txt/ChangeLog
@@ -122,6 +122,9 @@ JH/25 Bug 2827: Restrict size of References: header in bounce messages to 998
 JH/26 For a ${readsocket } in TLS mode, send a TLS Close Alert before the TCP
       close.  Previously a bare socket close was done.

+JH/27 Fix ${srs_encode ..}.  Previously it would give a bad result for one day
+      every 1024 days.
+

Exim version 4.96
-----------------
diff --git a/src/src/expand.c b/src/src/expand.c
index fe0fd1469..26df25795 100644
--- a/src/src/expand.c
+++ b/src/src/expand.c
@@ -3523,7 +3523,7 @@ switch(cond_type = identify_operator(&s, &opname))

     /* Match the given local_part against the SRS-encoded pattern */

-    re = regex_must_compile(US"^(?i)SRS0=([^=]+)=([A-Z2-7]+)=([^=]*)=(.*)$",
+    re = regex_must_compile(US"^(?i)SRS0=([^=]+)=([A-Z2-7]{2})=([^=]*)=(.*)$",
                 MCS_CASELESS | MCS_CACHEABLE, FALSE);
     md = pcre2_match_data_create(4+1, pcre_gen_ctx);
     if (pcre2_match(re, sub[0], PCRE2_ZERO_TERMINATED, 0, PCRE_EOPT,
@@ -7061,13 +7061,11 @@ while (*s)
       {
       struct timeval now;
       unsigned long i;
-      gstring * h = NULL;

       gettimeofday(&now, NULL);
-      for (unsigned long i = (now.tv_sec / 86400) & 0x3ff; i; i >>= 5)
-        h = string_catn(h, &base32_chars[i & 0x1f], 1);
-      if (h) while (h->ptr > 0)
-        g = string_catn(g, &h->s[--h->ptr], 1);
+      i = (now.tv_sec / 86400) & 0x3ff;
+      g = string_catn(g, &base32_chars[i >> 5], 1);
+      g = string_catn(g, &base32_chars[i & 0x1f], 1);
       }
     g = string_catn(g, US"=", 1);