Backport alignment consistent ipv6 masking from v4

diff --git a/src/lib/misc.c b/src/lib/misc.c
index b80b9ce468528f05b4dc2af26250431583d5282e..780cbfbf589da32781d2247a9261140b165fd38c 100644 (file)
--- a/src/lib/misc.c
+++ b/src/lib/misc.c
@@ -1253,9 +1253,9 @@ struct in_addr fr_inaddr_mask(struct in_addr const *ipaddr, uint8_t prefix)
  */
 struct in6_addr fr_in6addr_mask(struct in6_addr const *ipaddr, uint8_t prefix)
 {
-       uint64_t const *p = (uint64_t const *) ipaddr;
        uint64_t addr;                                  /* Needed for alignment */
        uint64_t ret[2], *o = ret;
+       uint8_t i = 0;
 
        if (prefix > 128) prefix = 128;
 
@@ -1264,16 +1264,30 @@ struct in6_addr fr_in6addr_mask(struct in6_addr const *ipaddr, uint8_t prefix)
 
        if (prefix >= 64) {
                prefix -= 64;
-               memcpy(&addr, p, sizeof(addr));         /* Needed for aligned access (ubsan) */
+               addr = (uint64_t)ipaddr->s6_addr[i] |
+                       ((uint64_t)ipaddr->s6_addr[i + 1] << 8) |
+                       ((uint64_t)ipaddr->s6_addr[i + 2] << 16) |
+                       ((uint64_t)ipaddr->s6_addr[i + 3] << 24) |
+                       ((uint64_t)ipaddr->s6_addr[i + 4] << 32) |
+                       ((uint64_t)ipaddr->s6_addr[i + 5] << 40) |
+                       ((uint64_t)ipaddr->s6_addr[i + 6] << 48) |
+                       ((uint64_t)ipaddr->s6_addr[i + 7] << 56);
                *o++ = 0xffffffffffffffffULL & addr;    /* lhs portion masked */
-               p++;
+               i+=8;
        } else {
                ret[1] = 0;                             /* rhs portion zeroed */
        }
 
        /* Max left shift is 63 else we get overflow */
        if (prefix > 0) {
-               memcpy(&addr, p, sizeof(addr));         /* Needed for aligned access (ubsan) */
+               addr = (uint64_t)ipaddr->s6_addr[i] |
+                       ((uint64_t)ipaddr->s6_addr[i + 1] << 8) |
+                       ((uint64_t)ipaddr->s6_addr[i + 2] << 16) |
+                       ((uint64_t)ipaddr->s6_addr[i + 3] << 24) |
+                       ((uint64_t)ipaddr->s6_addr[i + 4] << 32) |
+                       ((uint64_t)ipaddr->s6_addr[i + 5] << 40) |
+                       ((uint64_t)ipaddr->s6_addr[i + 6] << 48) |
+                       ((uint64_t)ipaddr->s6_addr[i + 7] << 56);
                *o = htonll(~((uint64_t)(0x0000000000000001ULL << (64 - prefix)) - 1)) & addr;
        } else {
                *o = 0;