diff --git a/error.h b/error.h
index 342a0d6..35ba011 100644
--- a/error.h
+++ b/error.h
@@ -67,7 +67,7 @@ static int unie(int e)
     #define LOG_E -1
     #define LOG_S 1
     #define LOG_L 2
-    static void LOG(int s, char *str, ...) {
+    static void LOG(int s, const char *str, ...) {
         if (params.debug >= s) {
             va_list args;
             va_start(args, str);
diff --git a/extend.c b/extend.c
index 07a3a81..b47fb6e 100644
--- a/extend.c
+++ b/extend.c
@@ -218,11 +218,11 @@ static bool check_ip(
         struct mphdr *ipset, const union sockaddr_u *dst)
 {
     int len = sizeof(dst->in.sin_addr);
-    char *data = (char *)&dst->in.sin_addr;
+    const char *data = (const char *)&dst->in.sin_addr;
     
     if (dst->sa.sa_family == AF_INET6) {
         len = sizeof(dst->in6.sin6_addr);
-        data = (char *)&dst->in6.sin6_addr;
+        data = (const char *)&dst->in6.sin6_addr;
     }
     if (mem_get(ipset, data, len * 8)) {
         return 1;
diff --git a/params.h b/params.h
index bacb24f..2e7b3a4 100644
--- a/params.h
+++ b/params.h
@@ -47,7 +47,7 @@ enum demode {
 };
 
 #ifdef STR_MODE
-char *demode_str[] = {
+static const char *demode_str[] = {
     "DESYNC_NONE",
     "DESYNC_SPLIT",
     "DESYNC_DISORDER",
diff --git a/proxy.c b/proxy.c
index 421f1c4..e3e0ba0 100644
--- a/proxy.c
+++ b/proxy.c
@@ -79,8 +79,8 @@ static inline char addr_equ(
 {
     if (a->sa.sa_family == AF_INET) {
         return 
-            *((uint32_t *)(&a->in.sin_addr)) ==
-            *((uint32_t *)(&b->in.sin_addr));
+            *((const uint32_t *)(&a->in.sin_addr)) ==
+            *((const uint32_t *)(&b->in.sin_addr));
     }
     return memcmp(&a->in6.sin6_addr, 
         &b->in6.sin6_addr, sizeof(b->in6.sin6_addr)) == 0;
@@ -118,7 +118,7 @@ static inline int nb_socket(int domain, int type)
 }
 
 
-static int resolve(char *host, int len, 
+static int resolve(const char *chost, int len, 
         union sockaddr_u *addr, int type) 
 {
     struct addrinfo hints = {0}, *res = 0;
@@ -129,21 +129,18 @@ static int resolve(char *host, int len,
         hints.ai_flags |= AI_NUMERICHOST;
     hints.ai_family = params.ipv6 ? AF_UNSPEC : AF_INET;
     
-    char rchar = host[len];
-    host[len] = '\0';
+    char host[len + 1];
+    host[len] = 0;
+    memcpy(host, chost, len);
+    
     LOG(LOG_S, "resolve: %s\n", host);
     
     if (getaddrinfo(host, 0, &hints, &res) || !res) {
-        host[len] = rchar;
         return -1;
     }
-    if (res->ai_addr->sa_family == AF_INET6)
-        addr->in6 = *(struct sockaddr_in6 *)res->ai_addr;
-    else
-        addr->in = *(struct sockaddr_in *)res->ai_addr;
+    memcpy(addr, res->ai_addr, SA_SIZE(res->ai_addr));
     freeaddrinfo(res);
     
-    host[len] = rchar;
     return 0;
 }
 
@@ -233,7 +230,7 @@ static int s4_get_addr(const char *buff,
     if (n < sizeof(struct s4_req) + 1) {
         return -1;
     }
-    struct s4_req *r = (struct s4_req *)buff;
+    const struct s4_req *r = (const struct s4_req *)buff;
     
     if (r->cmd != S_CMD_CONN) {
         return -1;
@@ -271,7 +268,7 @@ static int s5_get_addr(const char *buffer,
         LOG(LOG_E, "ss: request too small\n");
         return -S_ER_GEN;
     }
-    struct s5_req *r = (struct s5_req *)buffer;
+    const struct s5_req *r = (const struct s5_req *)buffer;
     
     size_t o = (r->atp == S_ATP_I4 ? S_SIZE_I4 : 
             (r->atp == S_ATP_ID ? r->dst.id.len + S_SIZE_ID : 
diff --git a/proxy.h b/proxy.h
index 66e98d7..d5ba47c 100644
--- a/proxy.h
+++ b/proxy.h
@@ -13,7 +13,7 @@
 #include "conev.h"
 
 #define SA_SIZE(s) \
-    (((struct sockaddr *)s)->sa_family == AF_INET6) ? \
+    (((const struct sockaddr *)s)->sa_family == AF_INET6) ? \
         sizeof(struct sockaddr_in6) : sizeof(struct sockaddr_in)
 
 #pragma pack(push, 1)