1 files changed, 53 insertions, 24 deletions

diff --git a/src/http/ngx_http_request.c b/src/http/ngx_http_request.c
index aea2228fd..fbb7915b3 100644
--- a/src/http/ngx_http_request.c
+++ b/src/http/ngx_http_request.c
@@ -1674,56 +1674,85 @@ static ssize_t
 ngx_http_validate_host(ngx_http_request_t *r, u_char **host, size_t len,
     ngx_uint_t alloc)
 {
-    u_char      *h, ch;
-    size_t       i, last;
-    ngx_uint_t   dot;
+    u_char  *h, ch;
+    size_t   i, dot_pos, host_len;
+
+    enum {
+        sw_usual = 0,
+        sw_literal,
+        sw_rest
+    } state;
+
+    dot_pos = len;
+    host_len = len;
 
-    last = len;
     h = *host;
-    dot = 0;
+
+    state = sw_usual;
 
     for (i = 0; i < len; i++) {
         ch = h[i];
 
-        if (ch == '.') {
-            if (dot) {
+        switch (ch) {
+
+        case '.':
+            if (dot_pos == i - 1) {
                 return 0;
             }
+            dot_pos = i;
+            break;
 
-            dot = 1;
-            continue;
-        }
+        case ':':
+            if (state == sw_usual) {
+                host_len = i;
+                state = sw_rest;
+            }
+            break;
 
-        dot = 0;
+        case '[':
+            if (i == 0) {
+                state = sw_literal;
+            }
+            break;
 
-        if (ch == ':') {
-            last = i;
-            continue;
-        }
+        case ']':
+            if (state == sw_literal) {
+                host_len = i + 1;
+                state = sw_rest;
+            }
+            break;
 
-        if (ngx_path_separator(ch) || ch == '\0') {
+        case '\0':
             return 0;
-        }
 
-        if (ch >= 'A' || ch < 'Z') {
-            alloc = 1;
+        default:
+
+            if (ngx_path_separator(ch)) {
+                return 0;
+            }
+
+            if (ch >= 'A' && ch <= 'Z') {
+                alloc = 1;
+            }
+
+            break;
         }
     }
 
-    if (dot) {
-        last--;
+    if (dot_pos == host_len - 1) {
+        host_len--;
     }
 
     if (alloc) {
-        *host = ngx_pnalloc(r->pool, last) ;
+        *host = ngx_pnalloc(r->pool, host_len);
         if (*host == NULL) {
             return -1;
         }
 
-        ngx_strlow(*host, h, last);
+        ngx_strlow(*host, h, host_len);
     }
 
-    return last;
+    return host_len;
 }