[or-cvs] [tor/master 1/2] A start at a patch for bug 1943 (alignment issues)

[nickm at torproject.org]

Author: Roger Dingledine <arma at torproject.org>
Date: Mon, 20 Sep 2010 18:40:32 -0400
Subject: A start at a patch for bug 1943 (alignment issues)
Commit: 47b23bd03e005c7a86ddd1dbcba619c1840a3232

---
 src/or/buffers.c       |    4 ++--
 src/or/circuitbuild.c  |    6 ++++--
 src/or/connection_or.c |    4 ++--
 src/or/geoip.c         |    1 +
 4 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/src/or/buffers.c b/src/or/buffers.c
index e842263..09ccb7c 100644
--- a/src/or/buffers.c
+++ b/src/or/buffers.c
@@ -1498,8 +1498,8 @@ fetch_from_buf_socks(buf_t *buf, socks_request_t *req,
         return -1;
       }
 
-      req->port = ntohs(*(uint16_t*)(buf->head->data+2));
-      destip = ntohl(*(uint32_t*)(buf->head->data+4));
+      req->port = ntohs(get_uint16(buf->head->data+2));
+      destip = ntohl(get_uint32(buf->head->data+4));
       if ((!req->port && req->command!=SOCKS_COMMAND_RESOLVE) || !destip) {
         log_warn(LD_APP,"socks4: Port or DestIP is zero. Rejecting.");
         return -1;
diff --git a/src/or/circuitbuild.c b/src/or/circuitbuild.c
index ef1bab3..14b0fb9 100644
--- a/src/or/circuitbuild.c
+++ b/src/or/circuitbuild.c
@@ -2308,8 +2308,8 @@ onionskin_answer(or_circuit_t *circ, uint8_t cell_type, const char *payload,
          cell_type == CELL_CREATED ? ONIONSKIN_REPLY_LEN : DIGEST_LEN*2);
 
   log_debug(LD_CIRC,"init digest forward 0x%.8x, backward 0x%.8x.",
-            (unsigned int)*(uint32_t*)(keys),
-            (unsigned int)*(uint32_t*)(keys+20));
+            (unsigned int)get_uint32(keys),
+            (unsigned int)get_uint32(keys+20));
   if (circuit_init_cpath_crypto(tmp_cpath, keys, 0)<0) {
     log_warn(LD_BUG,"Circuit initialization failed");
     tor_free(tmp_cpath);
@@ -2448,6 +2448,8 @@ router_handles_some_port(routerinfo_t *router, smartlist_t *needed_ports)
 
   for (i = 0; i < smartlist_len(needed_ports); ++i) {
     addr_policy_result_t r;
+    /* alignment issues aren't a worry for this dereference, since
+       needed_ports is explicitly a smartlist of uint16_t's */
     port = *(uint16_t *)smartlist_get(needed_ports, i);
     tor_assert(port);
     r = compare_addr_to_addr_policy(0, port, router->exit_policy);
diff --git a/src/or/connection_or.c b/src/or/connection_or.c
index 58e8ec7..6b648b1 100644
--- a/src/or/connection_or.c
+++ b/src/or/connection_or.c
@@ -147,7 +147,7 @@ void
 cell_pack(packed_cell_t *dst, const cell_t *src)
 {
   char *dest = dst->body;
-  *(uint16_t*)dest    = htons(src->circ_id);
+  set_uint16(dest, htons(src->circ_id));
   *(uint8_t*)(dest+2) = src->command;
   memcpy(dest+3, src->payload, CELL_PAYLOAD_SIZE);
 }
@@ -158,7 +158,7 @@ cell_pack(packed_cell_t *dst, const cell_t *src)
 static void
 cell_unpack(cell_t *dest, const char *src)
 {
-  dest->circ_id = ntohs(*(uint16_t*)(src));
+  dest->circ_id = ntohs(get_uint16(src));
   dest->command = *(uint8_t*)(src+2);
   memcpy(dest->payload, src+3, CELL_PAYLOAD_SIZE);
 }
diff --git a/src/or/geoip.c b/src/or/geoip.c
index d9c8a01..7f1052e 100644
--- a/src/or/geoip.c
+++ b/src/or/geoip.c
@@ -145,6 +145,7 @@ _geoip_compare_entries(const void **_a, const void **_b)
 static int
 _geoip_compare_key_to_entry(const void *_key, const void **_member)
 {
+  /* No alignment issue here, since _key really is a pointer to uint32_t */
   const uint32_t addr = *(uint32_t *)_key;
   const geoip_entry_t *entry = *_member;
   if (addr < entry->ip_low)
-- 
1.7.1