treewide: use log_*_errno whenever %m is in the format string

[elogind.git] / src / resolve / resolved-dns-packet.c

diff --git a/src/resolve/resolved-dns-packet.c b/src/resolve/resolved-dns-packet.c
index 0d276df8c951bade95c0131c3f899db7512cc904..a9bd8b13988dc31d6e5641921097be38fc3d6e08 100644 (file)
--- a/src/resolve/resolved-dns-packet.c
+++ b/src/resolve/resolved-dns-packet.c
@@ -22,6 +22,7 @@
 #include "utf8.h"
 #include "util.h"
 #include "strv.h"
+#include "unaligned.h"
 #include "resolved-dns-domain.h"
 #include "resolved-dns-packet.h"
 
@@ -311,8 +312,7 @@ int dns_packet_append_uint16(DnsPacket *p, uint16_t v, size_t *start) {
         if (r < 0)
                 return r;
 
-        ((uint8_t*) d)[0] = (uint8_t) (v >> 8);
-        ((uint8_t*) d)[1] = (uint8_t) v;
+        unaligned_write_be16(d, v);
 
         return 0;
 }
@@ -327,10 +327,7 @@ int dns_packet_append_uint32(DnsPacket *p, uint32_t v, size_t *start) {
         if (r < 0)
                 return r;
 
-        ((uint8_t*) d)[0] = (uint8_t) (v >> 24);
-        ((uint8_t*) d)[1] = (uint8_t) (v >> 16);
-        ((uint8_t*) d)[2] = (uint8_t) (v >> 8);
-        ((uint8_t*) d)[3] = (uint8_t) v;
+        unaligned_write_be32(d, v);
 
         return 0;
 }
@@ -433,9 +430,7 @@ int dns_packet_append_name(DnsPacket *p, const char *name,
                         goto fail;
 
                 if (allow_compression) {
-                        r = hashmap_ensure_allocated(&p->names,
-                                                     dns_name_hash_func,
-                                                     dns_name_compare_func);
+                        r = hashmap_ensure_allocated(&p->names, &dns_name_hash_ops);
                         if (r < 0)
                                 goto fail;
 
@@ -795,8 +790,8 @@ int dns_packet_read_uint16(DnsPacket *p, uint16_t *ret, size_t *start) {
         if (r < 0)
                 return r;
 
-        *ret = (((uint16_t) ((uint8_t*) d)[0]) << 8) |
-                ((uint16_t) ((uint8_t*) d)[1]);
+        *ret = unaligned_read_be16(d);
+
         return 0;
 }
 
@@ -810,10 +805,7 @@ int dns_packet_read_uint32(DnsPacket *p, uint32_t *ret, size_t *start) {
         if (r < 0)
                 return r;
 
-        *ret = (((uint32_t) ((uint8_t*) d)[0]) << 24) |
-               (((uint32_t) ((uint8_t*) d)[1]) << 16) |
-               (((uint32_t) ((uint8_t*) d)[2]) << 8) |
-                ((uint32_t) ((uint8_t*) d)[3]);
+        *ret = unaligned_read_be32(d);
 
         return 0;
 }
@@ -868,7 +860,7 @@ fail:
 
 int dns_packet_read_name(DnsPacket *p, char **_ret,
                          bool allow_compression, size_t *start) {
-        size_t saved_rindex, after_rindex = 0;
+        size_t saved_rindex, after_rindex = 0, jump_barrier;
         _cleanup_free_ char *ret = NULL;
         size_t n = 0, allocated = 0;
         bool first = true;
@@ -878,6 +870,7 @@ int dns_packet_read_name(DnsPacket *p, char **_ret,
         assert(_ret);
 
         saved_rindex = p->rindex;
+        jump_barrier = p->rindex;
 
         for (;;) {
                 uint8_t c, d;
@@ -924,7 +917,7 @@ int dns_packet_read_name(DnsPacket *p, char **_ret,
                                 goto fail;
 
                         ptr = (uint16_t) (c & ~0xc0) << 8 | (uint16_t) d;
-                        if (ptr < DNS_PACKET_HEADER_SIZE || ptr >= saved_rindex) {
+                        if (ptr < DNS_PACKET_HEADER_SIZE || ptr >= jump_barrier) {
                                 r = -EBADMSG;
                                 goto fail;
                         }
@@ -932,9 +925,13 @@ int dns_packet_read_name(DnsPacket *p, char **_ret,
                         if (after_rindex == 0)
                                 after_rindex = p->rindex;
 
+                        /* Jumps are limited to a "prior occurence" (RFC-1035 4.1.4) */
+                        jump_barrier = ptr;
                         p->rindex = ptr;
-                } else
+                } else {
+                        r = -EBADMSG;
                         goto fail;
+                }
         }
 
         if (!GREEDY_REALLOC(ret, allocated, n + 1)) {
@@ -1117,6 +1114,13 @@ int dns_packet_read_rr(DnsPacket *p, DnsResourceRecord **ret, size_t *start) {
         case DNS_TYPE_TXT: {
                 char *s;
 
+                /* RFC 1035 says that TXT must be at least one
+                   string. Reject empty records. */
+                if (!rdlength) {
+                        r = -EBADMSG;
+                        goto fail;
+                }
+
                 while (p->rindex < offset + rdlength) {
                         r = dns_packet_read_string(p, &s, NULL);
                         if (r < 0)