dnsmasq: backport fixes

[librecmc/librecmc.git] / package / network / services / dnsmasq / patches / 0118-Optimise-sort_rrset-for-the-case-where-the-RR-type-n.patch

diff --git a/package/network/services/dnsmasq/patches/0118-Optimise-sort_rrset-for-the-case-where-the-RR-type-n.patch b/package/network/services/dnsmasq/patches/0118-Optimise-sort_rrset-for-the-case-where-the-RR-type-n.patch
new file mode 100644 (file)
index 0000000..4c25f93
--- /dev/null
+++ b/package/network/services/dnsmasq/patches/0118-Optimise-sort_rrset-for-the-case-where-the-RR-type-n.patch
@@ -0,0 +1,99 @@
+From 8ebdc364afd886461d209284ad4c946ac65e6d2b Mon Sep 17 00:00:00 2001
+From: Simon Kelley <simon@thekelleys.org.uk>
+Date: Fri, 22 Jan 2021 18:50:43 +0000
+Subject: [PATCH 3/4] Optimise sort_rrset for the case where the RR type no
+ canonicalisation.
+
+Signed-off-by: Kevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>
+---
+ src/dnssec.c | 69 ++++++++++++++++++++++++++++++++++++----------------
+ 1 file changed, 48 insertions(+), 21 deletions(-)
+
+--- a/src/dnssec.c
++++ b/src/dnssec.c
+@@ -333,37 +333,64 @@ static int sort_rrset(struct dns_header
+         if (!CHECK_LEN(header, state2.ip, plen, rdlen2))
+           return rrsetidx; /* short packet */
+         state2.end = state2.ip + rdlen2; 
+-                
+-        while (1)
++
++        /* If the RR has no names in it then canonicalisation
++           is the identity function and we can compare
++           the RRs directly. If not we compare the 
++           canonicalised RRs one byte at a time. */
++        if (*rr_desc == (u16)-1)        
+           {
+-            int ok1, ok2;
++            int rdmin = rdlen1 > rdlen2 ? rdlen2 : rdlen1;
++            int cmp = memcmp(state1.ip, state2.ip, rdmin);
+             
+-            ok1 = get_rdata(header, plen, &state1);
+-            ok2 = get_rdata(header, plen, &state2);
+-
+-            if (!ok1 && !ok2)
++            if (cmp > 0 || (cmp == 0 && rdlen1 > rdmin))
++              {
++                unsigned char *tmp = rrset[i+1];
++                rrset[i+1] = rrset[i];
++                rrset[i] = tmp;
++                swap = 1;
++              }
++            else if (cmp == 0 && (rdlen1 == rdlen2))
+               {
+                 /* Two RRs are equal, remove one copy. RFC 4034, para 6.3 */
+                 for (j = i+1; j < rrsetidx-1; j++)
+                   rrset[j] = rrset[j+1];
+                 rrsetidx--;
+                 i--;
+-                break;
+               }
+-            else if (ok1 && (!ok2 || *state1.op > *state2.op)) 
+-              {
+-                unsigned char *tmp = rrset[i+1];
+-                rrset[i+1] = rrset[i];
+-                rrset[i] = tmp;
+-                swap = 1;
+-                break;
+-              }
+-            else if (ok2 && (!ok1 || *state2.op > *state1.op))
+-              break;
+-            
+-            /* arrive here when bytes are equal, go round the loop again
+-               and compare the next ones. */
+           }
++        else
++          /* Comparing canonicalised RRs, byte-at-a-time. */
++          while (1)
++            {
++              int ok1, ok2;
++              
++              ok1 = get_rdata(header, plen, &state1);
++              ok2 = get_rdata(header, plen, &state2);
++              
++              if (!ok1 && !ok2)
++                {
++                  /* Two RRs are equal, remove one copy. RFC 4034, para 6.3 */
++                  for (j = i+1; j < rrsetidx-1; j++)
++                    rrset[j] = rrset[j+1];
++                  rrsetidx--;
++                  i--;
++                  break;
++                }
++              else if (ok1 && (!ok2 || *state1.op > *state2.op)) 
++                {
++                  unsigned char *tmp = rrset[i+1];
++                  rrset[i+1] = rrset[i];
++                  rrset[i] = tmp;
++                  swap = 1;
++                  break;
++                }
++              else if (ok2 && (!ok1 || *state2.op > *state1.op))
++                break;
++              
++              /* arrive here when bytes are equal, go round the loop again
++                 and compare the next ones. */
++            }
+       }
+     } while (swap);
+