new file mode 100644
--- /dev/null
+++ b/src/core/ngx_inet.c
@@ -0,0 +1,273 @@
+
+/*
+ * Copyright (C) Igor Sysoev
+ */
+
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+
+
+ngx_inline static size_t ngx_sprint_uchar(u_char *text, u_char c, size_t len)
+{
+    size_t      n;
+    ngx_uint_t  c1, c2;
+
+    n = 0;
+
+    if (len == n) {
+        return n;
+    }
+
+    c1 = c / 100;
+
+    if (c1) {
+        *text++ = (u_char) (c1 + '0');
+        n++;
+
+        if (len == n) {
+            return n;
+        }
+    }
+
+    c2 = (c % 100) / 10;
+
+    if (c1 || c2) {
+        *text++ = (u_char) (c2 + '0');
+        n++;
+
+        if (len == n) {
+            return n;
+        }
+    }
+
+    c2 = c % 10;
+
+    *text++ = (u_char) (c2 + '0');
+    n++;
+
+    return n;
+}
+
+
+/* AF_INET only */
+
+size_t ngx_sock_ntop(int family, struct sockaddr *addr, u_char *text,
+                     size_t len)
+{
+    u_char              *p;
+    size_t               n;
+    ngx_uint_t           i;
+    struct sockaddr_in  *addr_in;
+
+    if (len == 0) {
+        return 0;
+    }
+
+    if (family != AF_INET) {
+        return 0;
+    }
+
+    addr_in = (struct sockaddr_in *) addr;
+    p = (u_char *) &addr_in->sin_addr;
+
+    if (len > INET_ADDRSTRLEN) {
+        len = INET_ADDRSTRLEN;
+    }
+
+    n = ngx_sprint_uchar(text, p[0], len);
+
+    i = 1;
+
+    do {
+        if (len == n) {
+            text[n - 1] = '\0';
+            return n;
+        }
+
+        text[n++] = '.';
+
+        if (len == n) {
+            text[n - 1] = '\0';
+            return n;
+        }
+
+        n += ngx_sprint_uchar(&text[n], p[i++], len - n);
+
+    } while (i < 4);
+
+    if (len == n) {
+        text[n] = '\0';
+        return n;
+    }
+
+    text[n] = '\0';
+
+    return n;
+
+#if 0
+    return ngx_snprintf((char *) text,
+                        len > INET_ADDRSTRLEN ? INET_ADDRSTRLEN : len,
+                        "%u.%u.%u.%u", p[0], p[1], p[2], p[3]);
+#endif
+}
+
+
+size_t ngx_inet_ntop(int family, void *addr, u_char *text, size_t len)
+{
+    u_char      *p;
+    size_t       n;
+    ngx_uint_t   i;
+
+    if (len == 0) {
+        return 0;
+    }
+
+    if (family != AF_INET) {
+        return 0;
+    }
+
+    p = (u_char *) addr;
+
+    if (len > INET_ADDRSTRLEN) {
+        len = INET_ADDRSTRLEN;
+    }
+
+    n = ngx_sprint_uchar(text, p[0], len);
+
+    i = 1;
+
+    do {
+        if (len == n) {
+            text[n - 1] = '\0';
+            return n;
+        }
+
+        text[n++] = '.';
+
+        if (len == n) {
+            text[n - 1] = '\0';
+            return n;
+        }
+
+        n += ngx_sprint_uchar(&text[n], p[i++], len - n);
+
+    } while (i < 4);
+
+    if (len == n) {
+        text[n] = '\0';
+        return n;
+    }
+
+    text[n] = '\0';
+
+    return n;
+
+#if 0
+    return ngx_snprintf((char *) text,
+                        len > INET_ADDRSTRLEN ? INET_ADDRSTRLEN : len,
+                        "%u.%u.%u.%u", p[0], p[1], p[2], p[3]);
+#endif
+}
+
+
+/* AF_INET only */
+
+ngx_int_t ngx_ptocidr(ngx_str_t *text, void *cidr)
+{
+    ngx_int_t         m;
+    ngx_uint_t        i;
+    ngx_inet_cidr_t  *in_cidr;
+
+    in_cidr = cidr;
+
+    for (i = 0; i < text->len; i++) {
+        if (text->data[i] == '/') {
+            break;
+        }
+    }
+
+    if (i == text->len) {
+        return NGX_ERROR;
+    }
+
+    text->data[i] = '\0';
+    in_cidr->addr = inet_addr((char *) text->data);
+    text->data[i] = '/';
+    if (in_cidr->addr == INADDR_NONE) {
+        return NGX_ERROR;
+    }
+
+    m = ngx_atoi(&text->data[i + 1], text->len - (i + 1));
+    if (m == NGX_ERROR) {
+        return NGX_ERROR;
+    }
+
+    if (m == 0) {
+
+        /* the x86 compilers use the shl instruction that shifts by modulo 32 */
+
+        in_cidr->mask = 0;
+        return NGX_OK;
+    }
+
+    in_cidr->mask = htonl((ngx_uint_t) (0 - (1 << (32 - m))));
+
+    return NGX_OK;
+}
+
+
+#if 0
+
+ngx_int_t ngx_inet_addr_port(ngx_conf_t *cf, ngx_command_t *cmd,
+                             ngx_str_t *addr_port)
+{
+    u_char          *host;
+    ngx_int_t        port;
+    ngx_uint_t       p;
+    struct hostent  *h;
+
+    for (p = 0; p < addr_port->len; p++) {
+        if (addr_port->data[p] == ':') {
+            break;
+        }
+    }
+
+    in_addr->host.len = p;
+    if (!(in_addr->host.data = ngx_palloc(pool, p + 1))) {
+        return NGX_ERROR;
+    }
+
+    ngx_cpystrn(in_addr->host.data, addr_port->data, p + 1);
+
+    if (p == addr_port->len) {
+        p = 0;
+    }
+
+    port = ngx_atoi(&addr[p], args[1].len - p);
+    if (port == NGX_ERROR && p == 0) {
+
+        /* default port */
+        iap->port = 0;
+
+    } else if ((port == NGX_ERROR && p != 0) /* "listen host:NONNUMBER" */
+               || (port < 1 || port > 65536)) { /* "listen 99999" */
+
+        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+                           "invalid port \"%s\" in \"%s\" directive, "
+                           "it must be a number between 1 and 65535",
+                           &addr[p], cmd->name.data);
+
+        return NGX_CONF_ERROR;
+
+    } else if (p == 0) {
+        ls->addr = INADDR_ANY;
+        ls->port = (in_port_t) port;
+        return NGX_CONF_OK;
+    }
+
+    return NGX_OK;
+}
+
+#endif