http: document index.cgi usage. no code changes
[oweals/busybox.git] / networking / httpd.c
index a7473ede9cb9e012bbad0379fa4b09a7e1c5c400..eded7b63f05dc882b741055fbdb06499f864b322 100644 (file)
@@ -5,62 +5,63 @@
  * Copyright (C) 2002,2003 Glenn Engel <glenne@engel.org>
  * Copyright (C) 2003-2006 Vladimir Oleynik <dzo@simtreas.ru>
  *
- * simplify patch stolen from libbb without using strdup
- *
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  *
  *****************************************************************************
  *
  * Typical usage:
- *   for non root user
- * httpd -p 8080 -h $HOME/public_html
- *   or for daemon start from rc script with uid=0:
- * httpd -u www
- * This is equivalent if www user have uid=80 to
- * httpd -p 80 -u 80 -h /www -c /etc/httpd.conf -r "Web Server Authentication"
- *
+ * For non root user:
+ *      httpd -p 8080 -h $HOME/public_html
+ * For daemon start from rc script with uid=0:
+ *      httpd -u www
+ * which is equivalent to (assuming user www has uid 80):
+ *      httpd -p 80 -u 80 -h $PWD -c /etc/httpd.conf -r "Web Server Authentication"
  *
- * When a url starts by "/cgi-bin/" it is assumed to be a cgi script.  The
- * server changes directory to the location of the script and executes it
+ * When an url starts with "/cgi-bin/" it is assumed to be a cgi script.
+ * The server changes directory to the location of the script and executes it
  * after setting QUERY_STRING and other environment variables.
  *
+ * If directory URL is given, no index.html is found and CGI support is enabled,
+ * cgi-bin/index.cgi will be run. Directory to list is ../$QUERY_STRING.
+ * See httpd_indexcgi.c for an example GCI code.
+ *
  * Doc:
  * "CGI Environment Variables": http://hoohoo.ncsa.uiuc.edu/cgi/env.html
  *
- * The server can also be invoked as a url arg decoder and html text encoder
+ * The applet can also be invoked as an url arg decoder and html text encoder
  * as follows:
- *  foo=`httpd -d $foo`           # decode "Hello%20World" as "Hello World"
- *  bar=`httpd -e "<Hello World>"`  # encode as "&#60Hello&#32World&#62"
+ *      foo=`httpd -d $foo`             # decode "Hello%20World" as "Hello World"
+ *      bar=`httpd -e "<Hello World>"`  # encode as "&#60Hello&#32World&#62"
  * Note that url encoding for arguments is not the same as html encoding for
- * presentation.  -d decodes a url-encoded argument while -e encodes in html
+ * presentation.  -d decodes an url-encoded argument while -e encodes in html
  * for page display.
  *
  * httpd.conf has the following format:
  *
+ * H:/serverroot     # define the server root. It will override -h
  * A:172.20.         # Allow address from 172.20.0.0/16
  * A:10.0.0.0/25     # Allow any address from 10.0.0.0-10.0.0.127
  * A:10.0.0.0/255.255.255.128  # Allow any address that previous set
  * A:127.0.0.1       # Allow local loopback connections
  * D:*               # Deny from other IP connections
+ * E404:/path/e404.html # /path/e404.html is the 404 (not found) error page
+ * I:index.html      # Show index.html when a directory is requested
+ *
+ * P:/url:[http://]hostname[:port]/new/path
+ *                   # When /urlXXXXXX is requested, reverse proxy
+ *                   # it to http://hostname[:port]/new/pathXXXXXX
+ *
  * /cgi-bin:foo:bar  # Require user foo, pwd bar on urls starting with /cgi-bin/
  * /adm:admin:setup  # Require user admin, pwd setup on urls starting with /adm/
  * /adm:toor:PaSsWd  # or user toor, pwd PaSsWd on urls starting with /adm/
  * .au:audio/basic   # additional mime type for audio.au files
- * *.php:/path/php   # running cgi.php scripts through an interpreter
+ * *.php:/path/php   # run xxx.php through an interpreter
  *
- * A/D may be as a/d or allow/deny - first char case insensitive
- * Deny IP rules take precedence over allow rules.
- *
- *
- * The Deny/Allow IP logic:
- *
- *  - Default is to allow all.  No addresses are denied unless
- *         denied with a D: rule.
- *  - Order of Deny/Allow rules is significant
+ * A/D may be as a/d or allow/deny - only first char matters.
+ * Deny/Allow IP logic:
+ *  - Default is to allow all (Allow all (A:*) is a no-op).
  *  - Deny rules take precedence over allow rules.
- *  - If a deny all rule (D:*) is used it acts as a catch-all for unmatched
- *       addresses.
- *  - Specification of Allow all (A:*) is a no-op
+ *  - "Deny all" rule (D:*) is applied last.
  *
  * Example:
  *   1. Allow only specified addresses
@@ -74,7 +75,7 @@
  *     D:2.3.4.        # deny from 2.3.4.0 - 2.3.4.255
  *     A:*             # (optional line added for clarity)
  *
- * If a sub directory contains a config file it is parsed and merged with
+ * If a sub directory contains config file, it is parsed and merged with
  * any existing settings as if it was appended to the original configuration.
  *
  * subdir paths are relative to the containing subdir and thus cannot
  * subdir http request, any merge is discarded when the process exits.  As a
  * result, the subdir settings only have a lifetime of a single request.
  *
+ * Custom error pages can contain an absolute path or be relative to
+ * 'home_httpd'. Error pages are to be static files (no CGI or script). Error
+ * page can only be defined in the root configuration file and are not taken
+ * into account in local (directories) config files.
  *
  * If -c is not set, an attempt will be made to open the default
  * root configuration file.  If -c is set and the file is not found, the
  * server exits with an error.
  *
  */
+ /* TODO: use TCP_CORK, parse_config() */
 
 #include "libbb.h"
 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
-#include <sys/sendfile.h>
+# include <sys/sendfile.h>
 #endif
-
-//#define DEBUG 1
-#define DEBUG 0
-
 /* amount of buffering in a pipe */
 #ifndef PIPE_BUF
 # define PIPE_BUF 4096
 #endif
 
-#define IOBUF_SIZE 8192    /* IO buffer */
+#define DEBUG 0
+
+#define IOBUF_SIZE 8192
+#if PIPE_BUF >= IOBUF_SIZE
+# error "PIPE_BUF >= IOBUF_SIZE"
+#endif
 
 #define HEADER_READ_TIMEOUT 60
 
-static const char default_path_httpd_conf[] ALIGN1 = "/etc";
-static const char httpd_conf[] ALIGN1 = "httpd.conf";
+static const char DEFAULT_PATH_HTTPD_CONF[] ALIGN1 = "/etc";
+static const char HTTPD_CONF[] ALIGN1 = "httpd.conf";
 static const char HTTP_200[] ALIGN1 = "HTTP/1.0 200 OK\r\n";
+static const char index_html[] ALIGN1 = "index.html";
 
 typedef struct has_next_ptr {
        struct has_next_ptr *next;
@@ -131,42 +139,152 @@ typedef struct Htaccess_IP {
        int allow_deny;
 } Htaccess_IP;
 
+/* Must have "next" as a first member */
+typedef struct Htaccess_Proxy {
+       struct Htaccess_Proxy *next;
+       char *url_from;
+       char *host_port;
+       char *url_to;
+} Htaccess_Proxy;
+
+enum {
+       HTTP_OK = 200,
+       HTTP_PARTIAL_CONTENT = 206,
+       HTTP_MOVED_TEMPORARILY = 302,
+       HTTP_BAD_REQUEST = 400,       /* malformed syntax */
+       HTTP_UNAUTHORIZED = 401, /* authentication needed, respond with auth hdr */
+       HTTP_NOT_FOUND = 404,
+       HTTP_FORBIDDEN = 403,
+       HTTP_REQUEST_TIMEOUT = 408,
+       HTTP_NOT_IMPLEMENTED = 501,   /* used for unrecognized requests */
+       HTTP_INTERNAL_SERVER_ERROR = 500,
+       HTTP_CONTINUE = 100,
+#if 0   /* future use */
+       HTTP_SWITCHING_PROTOCOLS = 101,
+       HTTP_CREATED = 201,
+       HTTP_ACCEPTED = 202,
+       HTTP_NON_AUTHORITATIVE_INFO = 203,
+       HTTP_NO_CONTENT = 204,
+       HTTP_MULTIPLE_CHOICES = 300,
+       HTTP_MOVED_PERMANENTLY = 301,
+       HTTP_NOT_MODIFIED = 304,
+       HTTP_PAYMENT_REQUIRED = 402,
+       HTTP_BAD_GATEWAY = 502,
+       HTTP_SERVICE_UNAVAILABLE = 503, /* overload, maintenance */
+#endif
+};
+
+static const uint16_t http_response_type[] ALIGN2 = {
+       HTTP_OK,
+#if ENABLE_FEATURE_HTTPD_RANGES
+       HTTP_PARTIAL_CONTENT,
+#endif
+       HTTP_MOVED_TEMPORARILY,
+       HTTP_REQUEST_TIMEOUT,
+       HTTP_NOT_IMPLEMENTED,
+#if ENABLE_FEATURE_HTTPD_BASIC_AUTH
+       HTTP_UNAUTHORIZED,
+#endif
+       HTTP_NOT_FOUND,
+       HTTP_BAD_REQUEST,
+       HTTP_FORBIDDEN,
+       HTTP_INTERNAL_SERVER_ERROR,
+#if 0   /* not implemented */
+       HTTP_CREATED,
+       HTTP_ACCEPTED,
+       HTTP_NO_CONTENT,
+       HTTP_MULTIPLE_CHOICES,
+       HTTP_MOVED_PERMANENTLY,
+       HTTP_NOT_MODIFIED,
+       HTTP_BAD_GATEWAY,
+       HTTP_SERVICE_UNAVAILABLE,
+#endif
+};
+
+static const struct {
+       const char *name;
+       const char *info;
+} http_response[ARRAY_SIZE(http_response_type)] = {
+       { "OK", NULL },
+#if ENABLE_FEATURE_HTTPD_RANGES
+       { "Partial Content", NULL },
+#endif
+       { "Found", NULL },
+       { "Request Timeout", "No request appeared within 60 seconds" },
+       { "Not Implemented", "The requested method is not recognized" },
+#if ENABLE_FEATURE_HTTPD_BASIC_AUTH
+       { "Unauthorized", "" },
+#endif
+       { "Not Found", "The requested URL was not found" },
+       { "Bad Request", "Unsupported method" },
+       { "Forbidden", ""  },
+       { "Internal Server Error", "Internal Server Error" },
+#if 0   /* not implemented */
+       { "Created" },
+       { "Accepted" },
+       { "No Content" },
+       { "Multiple Choices" },
+       { "Moved Permanently" },
+       { "Not Modified" },
+       { "Bad Gateway", "" },
+       { "Service Unavailable", "" },
+#endif
+};
+
 struct globals {
        int verbose;            /* must be int (used by getopt32) */
        smallint flg_deny_all;
 
-       unsigned rmt_ip;        /* used for IP-based allow/deny rules */
+       unsigned rmt_ip;        /* used for IP-based allow/deny rules */
        time_t last_mod;
-       off_t ContentLength;    /* -1 - unknown */
        char *rmt_ip_str;       /* for $REMOTE_ADDR and $REMOTE_PORT */
        const char *bind_addr_or_port;
 
        const char *g_query;
-       const char *configFile;
+       const char *opt_c_configFile;
        const char *home_httpd;
+       const char *index_page;
 
        const char *found_mime_type;
        const char *found_moved_temporarily;
        Htaccess_IP *ip_a_d;    /* config allow/deny lines */
 
-       USE_FEATURE_HTTPD_BASIC_AUTH(const char *g_realm;)
-       USE_FEATURE_HTTPD_BASIC_AUTH(char *remoteuser;)
-       USE_FEATURE_HTTPD_CGI(char *referer;)
-       USE_FEATURE_HTTPD_CGI(char *user_agent;)
+       IF_FEATURE_HTTPD_BASIC_AUTH(const char *g_realm;)
+       IF_FEATURE_HTTPD_BASIC_AUTH(char *remoteuser;)
+       IF_FEATURE_HTTPD_CGI(char *referer;)
+       IF_FEATURE_HTTPD_CGI(char *user_agent;)
+       IF_FEATURE_HTTPD_CGI(char *host;)
+       IF_FEATURE_HTTPD_CGI(char *http_accept;)
+       IF_FEATURE_HTTPD_CGI(char *http_accept_language;)
+
+       off_t file_size;        /* -1 - unknown */
+#if ENABLE_FEATURE_HTTPD_RANGES
+       off_t range_start;
+       off_t range_end;
+       off_t range_len;
+#endif
 
 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
        Htaccess *g_auth;       /* config user:password lines */
 #endif
-#if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
        Htaccess *mime_a;       /* config mime types */
-#endif
 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
        Htaccess *script_i;     /* config script interpreters */
 #endif
-       char *iobuf;            /* [IOBUF_SIZE] */
+       char *iobuf;            /* [IOBUF_SIZE] */
 #define hdr_buf bb_common_bufsiz1
        char *hdr_ptr;
        int hdr_cnt;
+#if ENABLE_FEATURE_HTTPD_ERROR_PAGES
+       const char *http_error_page[ARRAY_SIZE(http_response_type)];
+#endif
+#if ENABLE_FEATURE_HTTPD_PROXY
+       Htaccess_Proxy *proxy;
+#endif
+#if ENABLE_FEATURE_HTTPD_GZIP
+       /* client can handle gzip / we are going to send gzip */
+       smallint content_gzip;
+#endif
 };
 #define G (*ptr_to_globals)
 #define verbose           (G.verbose          )
@@ -174,17 +292,32 @@ struct globals {
 #define rmt_ip            (G.rmt_ip           )
 #define bind_addr_or_port (G.bind_addr_or_port)
 #define g_query           (G.g_query          )
-#define configFile        (G.configFile       )
+#define opt_c_configFile  (G.opt_c_configFile )
 #define home_httpd        (G.home_httpd       )
+#define index_page        (G.index_page       )
 #define found_mime_type   (G.found_mime_type  )
 #define found_moved_temporarily (G.found_moved_temporarily)
-#define ContentLength     (G.ContentLength    )
 #define last_mod          (G.last_mod         )
 #define ip_a_d            (G.ip_a_d           )
 #define g_realm           (G.g_realm          )
 #define remoteuser        (G.remoteuser       )
 #define referer           (G.referer          )
 #define user_agent        (G.user_agent       )
+#define host              (G.host             )
+#define http_accept       (G.http_accept      )
+#define http_accept_language (G.http_accept_language)
+#define file_size         (G.file_size        )
+#if ENABLE_FEATURE_HTTPD_RANGES
+#define range_start       (G.range_start      )
+#define range_end         (G.range_end        )
+#define range_len         (G.range_len        )
+#else
+enum {
+       range_start = 0,
+       range_end = MAXINT(off_t) - 1,
+       range_len = MAXINT(off_t),
+};
+#endif
 #define rmt_ip_str        (G.rmt_ip_str       )
 #define g_auth            (G.g_auth           )
 #define mime_a            (G.mime_a           )
@@ -192,77 +325,31 @@ struct globals {
 #define iobuf             (G.iobuf            )
 #define hdr_ptr           (G.hdr_ptr          )
 #define hdr_cnt           (G.hdr_cnt          )
+#define http_error_page   (G.http_error_page  )
+#define proxy             (G.proxy            )
+#if ENABLE_FEATURE_HTTPD_GZIP
+# define content_gzip     (G.content_gzip     )
+#else
+# define content_gzip     0
+#endif
 #define INIT_G() do { \
-       PTR_TO_GLOBALS = xzalloc(sizeof(G)); \
-       USE_FEATURE_HTTPD_BASIC_AUTH(g_realm = "Web Server Authentication";) \
+       SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
+       IF_FEATURE_HTTPD_BASIC_AUTH(g_realm = "Web Server Authentication";) \
        bind_addr_or_port = "80"; \
-       ContentLength = -1; \
+       index_page = index_html; \
+       file_size = -1; \
 } while (0)
 
 
-typedef enum {
-       HTTP_OK = 200,
-       HTTP_MOVED_TEMPORARILY = 302,
-       HTTP_BAD_REQUEST = 400,       /* malformed syntax */
-       HTTP_UNAUTHORIZED = 401, /* authentication needed, respond with auth hdr */
-       HTTP_NOT_FOUND = 404,
-       HTTP_FORBIDDEN = 403,
-       HTTP_REQUEST_TIMEOUT = 408,
-       HTTP_NOT_IMPLEMENTED = 501,   /* used for unrecognized requests */
-       HTTP_INTERNAL_SERVER_ERROR = 500,
-#if 0 /* future use */
-       HTTP_CONTINUE = 100,
-       HTTP_SWITCHING_PROTOCOLS = 101,
-       HTTP_CREATED = 201,
-       HTTP_ACCEPTED = 202,
-       HTTP_NON_AUTHORITATIVE_INFO = 203,
-       HTTP_NO_CONTENT = 204,
-       HTTP_MULTIPLE_CHOICES = 300,
-       HTTP_MOVED_PERMANENTLY = 301,
-       HTTP_NOT_MODIFIED = 304,
-       HTTP_PAYMENT_REQUIRED = 402,
-       HTTP_BAD_GATEWAY = 502,
-       HTTP_SERVICE_UNAVAILABLE = 503, /* overload, maintenance */
-       HTTP_RESPONSE_SETSIZE = 0xffffffff
-#endif
-} HttpResponseNum;
+#define STRNCASECMP(a, str) strncasecmp((a), (str), sizeof(str)-1)
 
-typedef struct {
-       HttpResponseNum type;
-       const char *name;
-       const char *info;
-} HttpEnumString;
-
-static const HttpEnumString httpResponseNames[] = {
-       { HTTP_OK, "OK", NULL },
-       { HTTP_MOVED_TEMPORARILY, "Found", "Directories must end with a slash." },
-       { HTTP_REQUEST_TIMEOUT, "Request Timeout",
-               "No request appeared within a reasonable time period." },
-       { HTTP_NOT_IMPLEMENTED, "Not Implemented",
-               "The requested method is not recognized by this server." },
-#if ENABLE_FEATURE_HTTPD_BASIC_AUTH
-       { HTTP_UNAUTHORIZED, "Unauthorized", "" },
-#endif
-       { HTTP_NOT_FOUND, "Not Found",
-               "The requested URL was not found on this server." },
-       { HTTP_BAD_REQUEST, "Bad Request", "Unsupported method." },
-       { HTTP_FORBIDDEN, "Forbidden", "" },
-       { HTTP_INTERNAL_SERVER_ERROR, "Internal Server Error",
-               "Internal Server Error" },
-#if 0                               /* not implemented */
-       { HTTP_CREATED, "Created" },
-       { HTTP_ACCEPTED, "Accepted" },
-       { HTTP_NO_CONTENT, "No Content" },
-       { HTTP_MULTIPLE_CHOICES, "Multiple Choices" },
-       { HTTP_MOVED_PERMANENTLY, "Moved Permanently" },
-       { HTTP_NOT_MODIFIED, "Not Modified" },
-       { HTTP_BAD_GATEWAY, "Bad Gateway", "" },
-       { HTTP_SERVICE_UNAVAILABLE, "Service Unavailable", "" },
-#endif
+/* Prototypes */
+enum {
+       SEND_HEADERS     = (1 << 0),
+       SEND_BODY        = (1 << 1),
+       SEND_HEADERS_AND_BODY = SEND_HEADERS + SEND_BODY,
 };
-
-
-#define STRNCASECMP(a, str) strncasecmp((a), (str), sizeof(str)-1)
+static void send_file_and_exit(const char *url, int what) NORETURN;
 
 static void free_llist(has_next_ptr **pptr)
 {
@@ -275,31 +362,32 @@ static void free_llist(has_next_ptr **pptr)
        *pptr = NULL;
 }
 
-#if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
- || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
- || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 static ALWAYS_INLINE void free_Htaccess_list(Htaccess **pptr)
 {
        free_llist((has_next_ptr**)pptr);
 }
-#endif
 
 static ALWAYS_INLINE void free_Htaccess_IP_list(Htaccess_IP **pptr)
 {
        free_llist((has_next_ptr**)pptr);
 }
 
-static int scan_ip(const char **ep, unsigned *ip, unsigned char endc)
+/* Returns presumed mask width in bits or < 0 on error.
+ * Updates strp, stores IP at provided pointer */
+static int scan_ip(const char **strp, unsigned *ipp, unsigned char endc)
 {
-       const char *p = *ep;
+       const char *p = *strp;
        int auto_mask = 8;
+       unsigned ip = 0;
        int j;
 
-       *ip = 0;
+       if (*p == '/')
+               return -auto_mask;
+
        for (j = 0; j < 4; j++) {
                unsigned octet;
 
-               if ((*p < '0' || *p > '9') && (*p != '/' || j == 0) && *p != '\0')
+               if ((*p < '0' || *p > '9') && *p != '/' && *p)
                        return -auto_mask;
                octet = 0;
                while (*p >= '0' && *p <= '9') {
@@ -311,312 +399,369 @@ static int scan_ip(const char **ep, unsigned *ip, unsigned char endc)
                }
                if (*p == '.')
                        p++;
-               if (*p != '/' && *p != '\0')
+               if (*p != '/' && *p)
                        auto_mask += 8;
-               *ip = ((*ip) << 8) | octet;
+               ip = (ip << 8) | octet;
        }
-       if (*p != '\0') {
+       if (*p) {
                if (*p != endc)
                        return -auto_mask;
                p++;
                if (*p == '\0')
                        return -auto_mask;
        }
-       *ep = p;
+       *ipp = ip;
+       *strp = p;
        return auto_mask;
 }
 
-static int scan_ip_mask(const char *ipm, unsigned *ip, unsigned *mask)
+/* Returns 0 on success. Stores IP and mask at provided pointers */
+static int scan_ip_mask(const char *str, unsigned *ipp, unsigned *maskp)
 {
        int i;
-       unsigned msk;
+       unsigned mask;
+       char *p;
 
-       i = scan_ip(&ipm, ip, '/');
+       i = scan_ip(&str, ipp, '/');
        if (i < 0)
                return i;
-       if (*ipm) {
-               const char *p = ipm;
-
-               i = 0;
-               while (*p) {
-                       if (*p < '0' || *p > '9') {
-                               if (*p == '.') {
-                                       i = scan_ip(&ipm, mask, 0);
-                                       return i != 32;
-                               }
-                               return -1;
-                       }
-                       i *= 10;
-                       i += *p - '0';
-                       p++;
+
+       if (*str) {
+               /* there is /xxx after dotted-IP address */
+               i = bb_strtou(str, &p, 10);
+               if (*p == '.') {
+                       /* 'xxx' itself is dotted-IP mask, parse it */
+                       /* (return 0 (success) only if it has N.N.N.N form) */
+                       return scan_ip(&str, maskp, '\0') - 32;
                }
+               if (*p)
+                       return -1;
        }
-       if (i > 32 || i < 0)
+
+       if (i > 32)
                return -1;
-       msk = 0x80000000;
-       *mask = 0;
-       while (i > 0) {
-               *mask |= msk;
-               msk >>= 1;
-               i--;
+
+       if (sizeof(unsigned) == 4 && i == 32) {
+               /* mask >>= 32 below may not work */
+               mask = 0;
+       } else {
+               mask = 0xffffffff;
+               mask >>= i;
        }
+       /* i == 0 -> *maskp = 0x00000000
+        * i == 1 -> *maskp = 0x80000000
+        * i == 4 -> *maskp = 0xf0000000
+        * i == 31 -> *maskp = 0xfffffffe
+        * i == 32 -> *maskp = 0xffffffff */
+       *maskp = (uint32_t)(~mask);
        return 0;
 }
 
 /*
  * Parse configuration file into in-memory linked list.
  *
- * The first non-white character is examined to determine if the config line
- * is one of the following:
- *    .ext:mime/type   # new mime type not compiled into httpd
- *    [adAD]:from      # ip address allow/deny, * for wildcard
- *    /path:user:pass  # username/password
- *
  * Any previous IP rules are discarded.
  * If the flag argument is not SUBDIR_PARSE then all /path and mime rules
  * are also discarded.  That is, previous settings are retained if flag is
  * SUBDIR_PARSE.
+ * Error pages are only parsed on the main config file.
  *
  * path   Path where to look for httpd.conf (without filename).
  * flag   Type of the parse request.
  */
-/* flag */
-#define FIRST_PARSE          0
-#define SUBDIR_PARSE         1
-#define SIGNALED_PARSE       2
-#define FIND_FROM_HTTPD_ROOT 3
+/* flag param: */
+enum {
+       FIRST_PARSE    = 0, /* path will be "/etc" */
+       SIGNALED_PARSE = 1, /* path will be "/etc" */
+       SUBDIR_PARSE   = 2, /* path will be derived from URL */
+};
 static void parse_conf(const char *path, int flag)
 {
+       /* internally used extra flag state */
+       enum { TRY_CURDIR_PARSE = 3 };
+
        FILE *f;
-#if ENABLE_FEATURE_HTTPD_BASIC_AUTH
-       Htaccess *prev;
-#endif
-#if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
- || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
- || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
-       Htaccess *cur;
-#endif
-       const char *cf = configFile;
+       const char *filename;
        char buf[160];
-       char *p0 = NULL;
-       char *c, *p;
-       Htaccess_IP *pip;
 
        /* discard old rules */
        free_Htaccess_IP_list(&ip_a_d);
        flg_deny_all = 0;
-#if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
- || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
- || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
        /* retain previous auth and mime config only for subdir parse */
        if (flag != SUBDIR_PARSE) {
+               free_Htaccess_list(&mime_a);
 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
                free_Htaccess_list(&g_auth);
 #endif
-#if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
-               free_Htaccess_list(&mime_a);
-#endif
 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
                free_Htaccess_list(&script_i);
 #endif
        }
-#endif
 
-       if (flag == SUBDIR_PARSE || cf == NULL) {
-               cf = alloca(strlen(path) + sizeof(httpd_conf) + 2);
-               if (cf == NULL) {
-                       if (flag == FIRST_PARSE)
-                               bb_error_msg_and_die(bb_msg_memory_exhausted);
-                       return;
-               }
-               sprintf((char *)cf, "%s/%s", path, httpd_conf);
+       filename = opt_c_configFile;
+       if (flag == SUBDIR_PARSE || filename == NULL) {
+               filename = alloca(strlen(path) + sizeof(HTTPD_CONF) + 2);
+               sprintf((char *)filename, "%s/%s", path, HTTPD_CONF);
        }
 
-       while ((f = fopen(cf, "r")) == NULL) {
-               if (flag == SUBDIR_PARSE || flag == FIND_FROM_HTTPD_ROOT) {
+       while ((f = fopen_for_read(filename)) == NULL) {
+               if (flag >= SUBDIR_PARSE) { /* SUBDIR or TRY_CURDIR */
                        /* config file not found, no changes to config */
                        return;
                }
-               if (configFile && flag == FIRST_PARSE) /* if -c option given */
-                       bb_perror_msg_and_die("%s", cf);
-               flag = FIND_FROM_HTTPD_ROOT;
-               cf = httpd_conf;
+               if (flag == FIRST_PARSE) {
+                       /* -c CONFFILE given, but CONFFILE doesn't exist? */
+                       if (opt_c_configFile)
+                               bb_simple_perror_msg_and_die(opt_c_configFile);
+                       /* else: no -c, thus we looked at /etc/httpd.conf,
+                        * and it's not there. try ./httpd.conf: */
+               }
+               flag = TRY_CURDIR_PARSE;
+               filename = HTTPD_CONF;
        }
 
 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
-       prev = g_auth;
-#endif
-       /* This could stand some work */
-       while ((p0 = fgets(buf, sizeof(buf), f)) != NULL) {
-               c = NULL;
-               for (p = p0; *p0 != '\0' && *p0 != '#'; p0++) {
-                       if (!isspace(*p0)) {
-                               *p++ = *p0;
-                               if (*p0 == ':' && c == NULL)
-                                       c = p;
+       /* in "/file:user:pass" lines, we prepend path in subdirs */
+       if (flag != SUBDIR_PARSE)
+               path = "";
+#endif
+       /* The lines can be:
+        *
+        * I:default_index_file
+        * H:http_home
+        * [AD]:IP[/mask]   # allow/deny, * for wildcard
+        * Ennn:error.html  # error page for status nnn
+        * P:/url:[http://]hostname[:port]/new/path # reverse proxy
+        * .ext:mime/type   # mime type
+        * *.php:/path/php  # run xxx.php through an interpreter
+        * /file:user:pass  # username and password
+        */
+       while (fgets(buf, sizeof(buf), f) != NULL) {
+               unsigned strlen_buf;
+               unsigned char ch;
+               char *after_colon;
+
+               { /* remove all whitespace, and # comments */
+                       char *p, *p0;
+
+                       p0 = buf;
+                       /* skip non-whitespace beginning. Often the whole line
+                        * is non-whitespace. We want this case to work fast,
+                        * without needless copying, therefore we don't merge
+                        * this operation into next while loop. */
+                       while ((ch = *p0) != '\0' && ch != '\n' && ch != '#'
+                        && ch != ' ' && ch != '\t'
+                       ) {
+                               p0++;
                        }
+                       p = p0;
+                       /* if we enter this loop, we have some whitespace.
+                        * discard it */
+                       while (ch != '\0' && ch != '\n' && ch != '#') {
+                               if (ch != ' ' && ch != '\t') {
+                                       *p++ = ch;
+                               }
+                               ch = *++p0;
+                       }
+                       *p = '\0';
+                       strlen_buf = p - buf;
+                       if (strlen_buf == 0)
+                               continue; /* empty line */
                }
-               *p = '\0';
 
-               /* test for empty or strange line */
-               if (c == NULL || *c == '\0')
+               after_colon = strchr(buf, ':');
+               /* strange line? */
+               if (after_colon == NULL || *++after_colon == '\0')
+                       goto config_error;
+
+               ch = (buf[0] & ~0x20); /* toupper if it's a letter */
+
+               if (ch == 'I') {
+                       if (index_page != index_html)
+                               free((char*)index_page);
+                       index_page = xstrdup(after_colon);
                        continue;
-               p0 = buf;
-               if (*p0 == 'd')
-                       *p0 = 'D';
-               if (*c == '*') {
-                       if (*p0 == 'D') {
-                               /* memorize deny all */
-                               flg_deny_all = 1;
-                       }
-                       /* skip default other "word:*" config lines */
+               }
+
+               /* do not allow jumping around using H in subdir's configs */
+               if (flag == FIRST_PARSE && ch == 'H') {
+                       home_httpd = xstrdup(after_colon);
+                       xchdir(home_httpd);
                        continue;
                }
 
-               if (*p0 == 'a')
-                       *p0 = 'A';
-               else if (*p0 != 'D' && *p0 != 'A'
-#if ENABLE_FEATURE_HTTPD_BASIC_AUTH
-                        && *p0 != '/'
-#endif
-#if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
-                        && *p0 != '.'
-#endif
-#if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
-                        && *p0 != '*'
-#endif
-                       )
-                        continue;
-               if (*p0 == 'A' || *p0 == 'D') {
-                       /* storing current config IP line */
-                       pip = xzalloc(sizeof(Htaccess_IP));
-                       if (pip) {
-                               if (scan_ip_mask(c, &(pip->ip), &(pip->mask))) {
-                                       /* syntax IP{/mask} error detected, protect all */
-                                       *p0 = 'D';
-                                       pip->mask = 0;
+               if (ch == 'A' || ch == 'D') {
+                       Htaccess_IP *pip;
+
+                       if (*after_colon == '*') {
+                               if (ch == 'D') {
+                                       /* memorize "deny all" */
+                                       flg_deny_all = 1;
                                }
-                               pip->allow_deny = *p0;
-                               if (*p0 == 'D') {
-                                       /* Deny:from_IP move top */
-                                       pip->next = ip_a_d;
+                               /* skip assumed "A:*", it is a default anyway */
+                               continue;
+                       }
+                       /* store "allow/deny IP/mask" line */
+                       pip = xzalloc(sizeof(*pip));
+                       if (scan_ip_mask(after_colon, &pip->ip, &pip->mask)) {
+                               /* IP{/mask} syntax error detected, protect all */
+                               ch = 'D';
+                               pip->mask = 0;
+                       }
+                       pip->allow_deny = ch;
+                       if (ch == 'D') {
+                               /* Deny:from_IP - prepend */
+                               pip->next = ip_a_d;
+                               ip_a_d = pip;
+                       } else {
+                               /* A:from_IP - append (thus all D's precedes A's) */
+                               Htaccess_IP *prev_IP = ip_a_d;
+                               if (prev_IP == NULL) {
                                        ip_a_d = pip;
                                } else {
-                                       /* add to bottom A:form_IP config line */
-                                       Htaccess_IP *prev_IP = ip_a_d;
-
-                                       if (prev_IP == NULL) {
-                                               ip_a_d = pip;
-                                       } else {
-                                               while (prev_IP->next)
-                                                       prev_IP = prev_IP->next;
-                                               prev_IP->next = pip;
-                                       }
+                                       while (prev_IP->next)
+                                               prev_IP = prev_IP->next;
+                                       prev_IP->next = pip;
                                }
                        }
                        continue;
                }
-#if ENABLE_FEATURE_HTTPD_BASIC_AUTH
-               if (*p0 == '/') {
-                       /* make full path from httpd root / current_path / config_line_path */
-                       cf = (flag == SUBDIR_PARSE ? path : "");
-                       p0 = malloc(strlen(cf) + (c - buf) + 2 + strlen(c));
-                       if (p0 == NULL)
-                               continue;
-                       c[-1] = '\0';
-                       sprintf(p0, "/%s%s", cf, buf);
 
-                       /* another call bb_simplify_path */
-                       cf = p = p0;
+#if ENABLE_FEATURE_HTTPD_ERROR_PAGES
+               if (flag == FIRST_PARSE && ch == 'E') {
+                       unsigned i;
+                       int status = atoi(buf + 1); /* error status code */
 
-                       do {
-                               if (*p == '/') {
-                                       if (*cf == '/') {    /* skip duplicate (or initial) slash */
-                                               continue;
-                                       } else if (*cf == '.') {
-                                               if (cf[1] == '/' || cf[1] == '\0') { /* remove extra '.' */
-                                                       continue;
-                                               } else if ((cf[1] == '.') && (cf[2] == '/' || cf[2] == '\0')) {
-                                                       ++cf;
-                                                       if (p > p0) {
-                                                               while (*--p != '/') /* omit previous dir */;
-                                                       }
-                                                       continue;
-                                               }
-                                       }
+                       if (status < HTTP_CONTINUE) {
+                               goto config_error;
+                       }
+                       /* then error page; find matching status */
+                       for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
+                               if (http_response_type[i] == status) {
+                                       /* We chdir to home_httpd, thus no need to
+                                        * concat_path_file(home_httpd, after_colon)
+                                        * here */
+                                       http_error_page[i] = xstrdup(after_colon);
+                                       break;
                                }
-                               *++p = *cf;
-                       } while (*++cf);
+                       }
+                       continue;
+               }
+#endif
 
-                       if ((p == p0) || (*p != '/')) {      /* not a trailing slash */
-                               ++p;                             /* so keep last character */
+#if ENABLE_FEATURE_HTTPD_PROXY
+               if (flag == FIRST_PARSE && ch == 'P') {
+                       /* P:/url:[http://]hostname[:port]/new/path */
+                       char *url_from, *host_port, *url_to;
+                       Htaccess_Proxy *proxy_entry;
+
+                       url_from = after_colon;
+                       host_port = strchr(after_colon, ':');
+                       if (host_port == NULL) {
+                               goto config_error;
                        }
-                       *p = '\0';
-                       sprintf(p0, "%s:%s", p0, c);
+                       *host_port++ = '\0';
+                       if (strncmp(host_port, "http://", 7) == 0)
+                               host_port += 7;
+                       if (*host_port == '\0') {
+                               goto config_error;
+                       }
+                       url_to = strchr(host_port, '/');
+                       if (url_to == NULL) {
+                               goto config_error;
+                       }
+                       *url_to = '\0';
+                       proxy_entry = xzalloc(sizeof(*proxy_entry));
+                       proxy_entry->url_from = xstrdup(url_from);
+                       proxy_entry->host_port = xstrdup(host_port);
+                       *url_to = '/';
+                       proxy_entry->url_to = xstrdup(url_to);
+                       proxy_entry->next = proxy;
+                       proxy = proxy_entry;
+                       continue;
                }
 #endif
+               /* the rest of directives are non-alphabetic,
+                * must avoid using "toupper'ed" ch */
+               ch = buf[0];
+
+               if (ch == '.' /* ".ext:mime/type" */
+#if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
+                || (ch == '*' && buf[1] == '.') /* "*.php:/path/php" */
+#endif
+               ) {
+                       char *p;
+                       Htaccess *cur;
 
-#if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
- || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
- || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
-               /* storing current config line */
-               cur = xzalloc(sizeof(Htaccess) + strlen(p0));
-               if (cur) {
-                       cf = strcpy(cur->before_colon, p0);
-                       c = strchr(cf, ':');
-                       *c++ = 0;
-                       cur->after_colon = c;
-#if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
-                       if (*cf == '.') {
-                               /* config .mime line move top for overwrite previous */
+                       cur = xzalloc(sizeof(*cur) /* includes space for NUL */ + strlen_buf);
+                       strcpy(cur->before_colon, buf);
+                       p = cur->before_colon + (after_colon - buf);
+                       p[-1] = '\0';
+                       cur->after_colon = p;
+                       if (ch == '.') {
+                               /* .mime line: prepend to mime_a list */
                                cur->next = mime_a;
                                mime_a = cur;
-                               continue;
                        }
-#endif
 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
-                       if (*cf == '*' && cf[1] == '.') {
-                               /* config script interpreter line move top for overwrite previous */
+                       else {
+                               /* script interpreter line: prepend to script_i list */
                                cur->next = script_i;
                                script_i = cur;
-                               continue;
                        }
 #endif
+                       continue;
+               }
+
 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
-                       free(p0);
-                       if (prev == NULL) {
-                               /* first line */
-                               g_auth = prev = cur;
-                       } else {
-                               /* sort path, if current lenght eq or bigger then move up */
-                               Htaccess *prev_hti = g_auth;
-                               size_t l = strlen(cf);
-                               Htaccess *hti;
-
-                               for (hti = prev_hti; hti; hti = hti->next) {
-                                       if (l >= strlen(hti->before_colon)) {
-                                               /* insert before hti */
-                                               cur->next = hti;
-                                               if (prev_hti != hti) {
-                                                       prev_hti->next = cur;
-                                               } else {
-                                                       /* insert as top */
-                                                       g_auth = cur;
-                                               }
+               if (ch == '/') { /* "/file:user:pass" */
+                       char *p;
+                       Htaccess *cur;
+                       unsigned file_len;
+
+                       /* note: path is "" unless we are in SUBDIR parse,
+                        * otherwise it does NOT start with "/" */
+                       cur = xzalloc(sizeof(*cur) /* includes space for NUL */
+                               + 1 + strlen(path)
+                               + strlen_buf
+                               );
+                       /* form "/path/file" */
+                       sprintf(cur->before_colon, "/%s%.*s",
+                               path,
+                               (int) (after_colon - buf - 1), /* includes "/", but not ":" */
+                               buf);
+                       /* canonicalize it */
+                       p = bb_simplify_abs_path_inplace(cur->before_colon);
+                       file_len = p - cur->before_colon;
+                       /* add "user:pass" after NUL */
+                       strcpy(++p, after_colon);
+                       cur->after_colon = p;
+
+                       /* insert cur into g_auth */
+                       /* g_auth is sorted by decreased filename length */
+                       {
+                               Htaccess *auth, **authp;
+
+                               authp = &g_auth;
+                               while ((auth = *authp) != NULL) {
+                                       if (file_len >= strlen(auth->before_colon)) {
+                                               /* insert cur before auth */
+                                               cur->next = auth;
                                                break;
                                        }
-                                       if (prev_hti != hti)
-                                               prev_hti = prev_hti->next;
-                               }
-                               if (!hti) {       /* not inserted, add to bottom */
-                                       prev->next = cur;
-                                       prev = cur;
+                                       authp = &auth->next;
                                }
+                               *authp = cur;
                        }
-#endif
+                       continue;
                }
-#endif
-        }
+#endif /* BASIC_AUTH */
+
+               /* the line is not recognized */
+ config_error:
+               bb_error_msg("config error '%s' in '%s'", buf, filename);
+        } /* while (fgets) */
+
         fclose(f);
 }
 
@@ -638,20 +783,22 @@ static char *encodeString(const char *string)
        char *p = out;
        char ch;
 
-       while ((ch = *string++)) {
-               // very simple check for what to encode
-               if (isalnum(ch)) *p++ = ch;
-               else p += sprintf(p, "&#%d;", (unsigned char) ch);
+       while ((ch = *string++) != '\0') {
+               /* very simple check for what to encode */
+               if (isalnum(ch))
+                       *p++ = ch;
+               else
+                       p += sprintf(p, "&#%d;", (unsigned char) ch);
        }
        *p = '\0';
        return out;
 }
-#endif          /* FEATURE_HTTPD_ENCODE_URL_STR */
+#endif
 
 /*
  * Given a URL encoded string, convert it to plain ascii.
  * Since decoding always makes strings smaller, the decode is done in-place.
- * Thus, callers should strdup() the argument if they do not want the
+ * Thus, callers should xstrdup() the argument if they do not want the
  * argument modified.  The return is the original pointer, allowing this
  * function to be easily used as arguments to other functions.
  *
@@ -662,20 +809,23 @@ static char *encodeString(const char *string)
  */
 static unsigned hex_to_bin(unsigned char c)
 {
-       unsigned v = c | 0x20; /* lowercase */
-       v = v - '0';
+       unsigned v;
+
+       v = c - '0';
        if (v <= 9)
                return v;
-       v = v + ('0' - 'a');
+       /* c | 0x20: letters to lower case, non-letters
+        * to (potentially different) non-letters */
+       v = (unsigned)(c | 0x20) - 'a';
        if (v <= 5)
                return v + 10;
        return ~0;
-}
 /* For testing:
-void t(char c) { printf("'%c' %u\n", c, hex_to_bin(c)); }
-int main() { t('0'); t('9'); t('A'); t('F'); t('a'); t('f');
+void t(char c) { printf("'%c'(%u) %u\n", c, c, hex_to_bin(c)); }
+int main() { t(0x10); t(0x20); t('0'); t('9'); t('A'); t('F'); t('a'); t('f');
 t('0'-1); t('9'+1); t('A'-1); t('F'+1); t('a'-1); t('f'+1); return 0; }
 */
+}
 static char *decodeString(char *orig, int option_d)
 {
        /* note that decoded string is always shorter than original */
@@ -769,7 +919,7 @@ static void decodeBase64(char *Data)
  */
 static int openServer(void)
 {
-       int n = bb_strtou(bind_addr_or_port, NULL, 10);
+       unsigned n = bb_strtou(bind_addr_or_port, NULL, 10);
        if (!errno && n && n <= 0xffff)
                n = create_and_bind_stream_or_die(NULL, n);
        else
@@ -781,15 +931,18 @@ static int openServer(void)
 /*
  * Log the connection closure and exit.
  */
-static void log_and_exit(void) ATTRIBUTE_NORETURN;
+static void log_and_exit(void) NORETURN;
 static void log_and_exit(void)
 {
        /* Paranoia. IE said to be buggy. It may send some extra data
         * or be confused by us just exiting without SHUT_WR. Oh well. */
        shutdown(1, SHUT_WR);
+       /* Why??
+       (this also messes up stdin when user runs httpd -i from terminal)
        ndelay_on(0);
-       while (read(0, iobuf, IOBUF_SIZE) > 0)
+       while (read(STDIN_FILENO, iobuf, IOBUF_SIZE) > 0)
                continue;
+       */
 
        if (verbose > 2)
                bb_error_msg("closed");
@@ -802,24 +955,29 @@ static void log_and_exit(void)
  * IE will puke big-time if the headers are not sent in one packet and the
  * second packet is delayed for any reason.
  * responseNum - the result code to send.
- * Return result of write().
  */
-static void send_headers(HttpResponseNum responseNum)
+static void send_headers(int responseNum)
 {
        static const char RFC1123FMT[] ALIGN1 = "%a, %d %b %Y %H:%M:%S GMT";
 
        const char *responseString = "";
        const char *infoString = NULL;
        const char *mime_type;
+#if ENABLE_FEATURE_HTTPD_ERROR_PAGES
+       const char *error_page = NULL;
+#endif
        unsigned i;
-       time_t timer = time(0);
+       time_t timer = time(NULL);
        char tmp_str[80];
        int len;
 
-       for (i = 0; i < ARRAY_SIZE(httpResponseNames); i++) {
-               if (httpResponseNames[i].type == responseNum) {
-                       responseString = httpResponseNames[i].name;
-                       infoString = httpResponseNames[i].info;
+       for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
+               if (http_response_type[i] == responseNum) {
+                       responseString = http_response[i].name;
+                       infoString = http_response[i].info;
+#if ENABLE_FEATURE_HTTPD_ERROR_PAGES
+                       error_page = http_error_page[i];
+#endif
                        break;
                }
        }
@@ -851,11 +1009,45 @@ static void send_headers(HttpResponseNum responseNum)
                                (g_query ? g_query : ""));
        }
 
-       if (ContentLength != -1) {    /* file */
+#if ENABLE_FEATURE_HTTPD_ERROR_PAGES
+       if (error_page && access(error_page, R_OK) == 0) {
+               strcat(iobuf, "\r\n");
+               len += 2;
+
+               if (DEBUG)
+                       fprintf(stderr, "headers: '%s'\n", iobuf);
+               full_write(STDOUT_FILENO, iobuf, len);
+               if (DEBUG)
+                       fprintf(stderr, "writing error page: '%s'\n", error_page);
+               return send_file_and_exit(error_page, SEND_BODY);
+       }
+#endif
+
+       if (file_size != -1) {    /* file */
                strftime(tmp_str, sizeof(tmp_str), RFC1123FMT, gmtime(&last_mod));
-               len += sprintf(iobuf + len, "Last-Modified: %s\r\n%s %"OFF_FMT"d\r\n",
-                       tmp_str, "Content-length:", ContentLength);
+#if ENABLE_FEATURE_HTTPD_RANGES
+               if (responseNum == HTTP_PARTIAL_CONTENT) {
+                       len += sprintf(iobuf + len, "Content-Range: bytes %"OFF_FMT"u-%"OFF_FMT"u/%"OFF_FMT"u\r\n",
+                                       range_start,
+                                       range_end,
+                                       file_size);
+                       file_size = range_end - range_start + 1;
+               }
+#endif
+               len += sprintf(iobuf + len,
+#if ENABLE_FEATURE_HTTPD_RANGES
+                       "Accept-Ranges: bytes\r\n"
+#endif
+                       "Last-Modified: %s\r\n%s %"OFF_FMT"u\r\n",
+                               tmp_str,
+                               content_gzip ? "Transfer-length:" : "Content-length:",
+                               file_size
+               );
        }
+
+       if (content_gzip)
+               len += sprintf(iobuf + len, "Content-Encoding: gzip\r\n");
+
        iobuf[len++] = '\r';
        iobuf[len++] = '\n';
        if (infoString) {
@@ -867,16 +1059,17 @@ static void send_headers(HttpResponseNum responseNum)
        }
        if (DEBUG)
                fprintf(stderr, "headers: '%s'\n", iobuf);
-       if (full_write(1, iobuf, len) != len) {
+       if (full_write(STDOUT_FILENO, iobuf, len) != len) {
                if (verbose > 1)
                        bb_perror_msg("error");
                log_and_exit();
        }
 }
 
-static void send_headers_and_exit(HttpResponseNum responseNum) ATTRIBUTE_NORETURN;
-static void send_headers_and_exit(HttpResponseNum responseNum)
+static void send_headers_and_exit(int responseNum) NORETURN;
+static void send_headers_and_exit(int responseNum)
 {
+       IF_FEATURE_HTTPD_GZIP(content_gzip = 0;)
        send_headers(responseNum);
        log_and_exit();
 }
@@ -893,9 +1086,10 @@ static int get_line(void)
        int count = 0;
        char c;
 
+       alarm(HEADER_READ_TIMEOUT);
        while (1) {
                if (hdr_cnt <= 0) {
-                       hdr_cnt = safe_read(0, hdr_buf, sizeof(hdr_buf));
+                       hdr_cnt = safe_read(STDIN_FILENO, hdr_buf, sizeof(hdr_buf));
                        if (hdr_cnt <= 0)
                                break;
                        hdr_ptr = hdr_buf;
@@ -907,7 +1101,7 @@ static int get_line(void)
                        continue;
                if (c == '\n') {
                        iobuf[count] = '\0';
-                       return count;
+                       break;
                }
                if (count < (IOBUF_SIZE - 1))      /* check overflow */
                        count++;
@@ -915,7 +1109,185 @@ static int get_line(void)
        return count;
 }
 
+#if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
+
+/* gcc 4.2.1 fares better with NOINLINE */
+static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len) NORETURN;
+static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len)
+{
+       enum { FROM_CGI = 1, TO_CGI = 2 }; /* indexes in pfd[] */
+       struct pollfd pfd[3];
+       int out_cnt; /* we buffer a bit of initial CGI output */
+       int count;
+
+       /* iobuf is used for CGI -> network data,
+        * hdr_buf is for network -> CGI data (POSTDATA) */
+
+       /* If CGI dies, we still want to correctly finish reading its output
+        * and send it to the peer. So please no SIGPIPEs! */
+       signal(SIGPIPE, SIG_IGN);
+
+       // We inconsistently handle a case when more POSTDATA from network
+       // is coming than we expected. We may give *some part* of that
+       // extra data to CGI.
+
+       //if (hdr_cnt > post_len) {
+       //      /* We got more POSTDATA from network than we expected */
+       //      hdr_cnt = post_len;
+       //}
+       post_len -= hdr_cnt;
+       /* post_len - number of POST bytes not yet read from network */
+
+       /* NB: breaking out of this loop jumps to log_and_exit() */
+       out_cnt = 0;
+       while (1) {
+               memset(pfd, 0, sizeof(pfd));
+
+               pfd[FROM_CGI].fd = fromCgi_rd;
+               pfd[FROM_CGI].events = POLLIN;
+
+               if (toCgi_wr) {
+                       pfd[TO_CGI].fd = toCgi_wr;
+                       if (hdr_cnt > 0) {
+                               pfd[TO_CGI].events = POLLOUT;
+                       } else if (post_len > 0) {
+                               pfd[0].events = POLLIN;
+                       } else {
+                               /* post_len <= 0 && hdr_cnt <= 0:
+                                * no more POST data to CGI,
+                                * let CGI see EOF on CGI's stdin */
+                               if (toCgi_wr != fromCgi_rd)
+                                       close(toCgi_wr);
+                               toCgi_wr = 0;
+                       }
+               }
+
+               /* Now wait on the set of sockets */
+               count = safe_poll(pfd, toCgi_wr ? TO_CGI+1 : FROM_CGI+1, -1);
+               if (count <= 0) {
+#if 0
+                       if (safe_waitpid(pid, &status, WNOHANG) <= 0) {
+                               /* Weird. CGI didn't exit and no fd's
+                                * are ready, yet poll returned?! */
+                               continue;
+                       }
+                       if (DEBUG && WIFEXITED(status))
+                               bb_error_msg("CGI exited, status=%d", WEXITSTATUS(status));
+                       if (DEBUG && WIFSIGNALED(status))
+                               bb_error_msg("CGI killed, signal=%d", WTERMSIG(status));
+#endif
+                       break;
+               }
+
+               if (pfd[TO_CGI].revents) {
+                       /* hdr_cnt > 0 here due to the way pfd[TO_CGI].events set */
+                       /* Have data from peer and can write to CGI */
+                       count = safe_write(toCgi_wr, hdr_ptr, hdr_cnt);
+                       /* Doesn't happen, we dont use nonblocking IO here
+                        *if (count < 0 && errno == EAGAIN) {
+                        *      ...
+                        *} else */
+                       if (count > 0) {
+                               hdr_ptr += count;
+                               hdr_cnt -= count;
+                       } else {
+                               /* EOF/broken pipe to CGI, stop piping POST data */
+                               hdr_cnt = post_len = 0;
+                       }
+               }
+
+               if (pfd[0].revents) {
+                       /* post_len > 0 && hdr_cnt == 0 here */
+                       /* We expect data, prev data portion is eaten by CGI
+                        * and there *is* data to read from the peer
+                        * (POSTDATA) */
+                       //count = post_len > (int)sizeof(hdr_buf) ? (int)sizeof(hdr_buf) : post_len;
+                       //count = safe_read(STDIN_FILENO, hdr_buf, count);
+                       count = safe_read(STDIN_FILENO, hdr_buf, sizeof(hdr_buf));
+                       if (count > 0) {
+                               hdr_cnt = count;
+                               hdr_ptr = hdr_buf;
+                               post_len -= count;
+                       } else {
+                               /* no more POST data can be read */
+                               post_len = 0;
+                       }
+               }
+
+               if (pfd[FROM_CGI].revents) {
+                       /* There is something to read from CGI */
+                       char *rbuf = iobuf;
+
+                       /* Are we still buffering CGI output? */
+                       if (out_cnt >= 0) {
+                               /* HTTP_200[] has single "\r\n" at the end.
+                                * According to http://hoohoo.ncsa.uiuc.edu/cgi/out.html,
+                                * CGI scripts MUST send their own header terminated by
+                                * empty line, then data. That's why we have only one
+                                * <cr><lf> pair here. We will output "200 OK" line
+                                * if needed, but CGI still has to provide blank line
+                                * between header and body */
+
+                               /* Must use safe_read, not full_read, because
+                                * CGI may output a few first bytes and then wait
+                                * for POSTDATA without closing stdout.
+                                * With full_read we may wait here forever. */
+                               count = safe_read(fromCgi_rd, rbuf + out_cnt, PIPE_BUF - 8);
+                               if (count <= 0) {
+                                       /* eof (or error) and there was no "HTTP",
+                                        * so write it, then write received data */
+                                       if (out_cnt) {
+                                               full_write(STDOUT_FILENO, HTTP_200, sizeof(HTTP_200)-1);
+                                               full_write(STDOUT_FILENO, rbuf, out_cnt);
+                                       }
+                                       break; /* CGI stdout is closed, exiting */
+                               }
+                               out_cnt += count;
+                               count = 0;
+                               /* "Status" header format is: "Status: 302 Redirected\r\n" */
+                               if (out_cnt >= 8 && memcmp(rbuf, "Status: ", 8) == 0) {
+                                       /* send "HTTP/1.0 " */
+                                       if (full_write(STDOUT_FILENO, HTTP_200, 9) != 9)
+                                               break;
+                                       rbuf += 8; /* skip "Status: " */
+                                       count = out_cnt - 8;
+                                       out_cnt = -1; /* buffering off */
+                               } else if (out_cnt >= 4) {
+                                       /* Did CGI add "HTTP"? */
+                                       if (memcmp(rbuf, HTTP_200, 4) != 0) {
+                                               /* there is no "HTTP", do it ourself */
+                                               if (full_write(STDOUT_FILENO, HTTP_200, sizeof(HTTP_200)-1) != sizeof(HTTP_200)-1)
+                                                       break;
+                                       }
+                                       /* Commented out:
+                                       if (!strstr(rbuf, "ontent-")) {
+                                               full_write(s, "Content-type: text/plain\r\n\r\n", 28);
+                                       }
+                                        * Counter-example of valid CGI without Content-type:
+                                        * echo -en "HTTP/1.0 302 Found\r\n"
+                                        * echo -en "Location: http://www.busybox.net\r\n"
+                                        * echo -en "\r\n"
+                                        */
+                                       count = out_cnt;
+                                       out_cnt = -1; /* buffering off */
+                               }
+                       } else {
+                               count = safe_read(fromCgi_rd, rbuf, PIPE_BUF);
+                               if (count <= 0)
+                                       break;  /* eof (or error) */
+                       }
+                       if (full_write(STDOUT_FILENO, rbuf, count) != count)
+                               break;
+                       if (DEBUG)
+                               fprintf(stderr, "cgi read %d bytes: '%.*s'\n", count, count, rbuf);
+               } /* if (pfd[FROM_CGI].revents) */
+       } /* while (1) */
+       log_and_exit();
+}
+#endif
+
 #if ENABLE_FEATURE_HTTPD_CGI
+
 static void setenv1(const char *name, const char *value)
 {
        setenv(name, value ? value : "", 1);
@@ -925,75 +1297,71 @@ static void setenv1(const char *name, const char *value)
  * Spawn CGI script, forward CGI's stdin/out <=> network
  *
  * Environment variables are set up and the script is invoked with pipes
- * for stdin/stdout.  If a post is being done the script is fed the POST
+ * for stdin/stdout.  If a POST is being done the script is fed the POST
  * data in addition to setting the QUERY_STRING variable (for GETs or POSTs).
  *
  * Parameters:
  * const char *url              The requested URL (with leading /).
- * int bodyLen                  Length of the post body.
+ * int post_len                 Length of the POST body.
  * const char *cookie           For set HTTP_COOKIE.
  * const char *content_type     For set CONTENT_TYPE.
  */
 static void send_cgi_and_exit(
                const char *url,
                const char *request,
-               int bodyLen,
+               int post_len,
                const char *cookie,
-               const char *content_type) ATTRIBUTE_NORETURN;
+               const char *content_type) NORETURN;
 static void send_cgi_and_exit(
                const char *url,
                const char *request,
-               int bodyLen,
+               int post_len,
                const char *cookie,
                const char *content_type)
 {
-       struct { int rd; int wr; } fromCgi;  /* CGI -> httpd pipe */
-       struct { int rd; int wr; } toCgi;    /* httpd -> CGI pipe */
-       char *fullpath;
+       struct fd_pair fromCgi;  /* CGI -> httpd pipe */
+       struct fd_pair toCgi;    /* httpd -> CGI pipe */
        char *script;
-       char *purl;
-       int buf_count;
-       int status;
-       int pid = 0;
+       int pid;
+
+       /* Make a copy. NB: caller guarantees:
+        * url[0] == '/', url[1] != '/' */
+       url = xstrdup(url);
 
        /*
         * We are mucking with environment _first_ and then vfork/exec,
-        * this allows us to use vfork safely. Parent don't care about
+        * this allows us to use vfork safely. Parent doesn't care about
         * these environment changes anyway.
         */
 
-       /*
-        * Find PATH_INFO.
-        */
-       purl = xstrdup(url);
-       script = purl;
+       /* Check for [dirs/]script.cgi/PATH_INFO */
+       script = (char*)url;
        while ((script = strchr(script + 1, '/')) != NULL) {
-               /* have script.cgi/PATH_INFO or dirs/script.cgi[/PATH_INFO] */
-               struct stat sb;
-
                *script = '\0';
-               if (!is_directory(purl + 1, 1, &sb)) {
+               if (!is_directory(url + 1, 1, NULL)) {
                        /* not directory, found script.cgi/PATH_INFO */
                        *script = '/';
                        break;
                }
-               *script = '/';          /* is directory, find next '/' */
+               *script = '/'; /* is directory, find next '/' */
        }
-       setenv1("PATH_INFO", script);   /* set /PATH_INFO or "" */
+       setenv1("PATH_INFO", script);   /* set to /PATH_INFO or "" */
        setenv1("REQUEST_METHOD", request);
        if (g_query) {
-               putenv(xasprintf("%s=%s?%s", "REQUEST_URI", purl, g_query));
+               putenv(xasprintf("%s=%s?%s", "REQUEST_URI", url, g_query));
        } else {
-               setenv1("REQUEST_URI", purl);
+               setenv1("REQUEST_URI", url);
        }
        if (script != NULL)
                *script = '\0';         /* cut off /PATH_INFO */
 
-       /* SCRIPT_FILENAME required by PHP in CGI mode */
-       fullpath = concat_path_file(home_httpd, purl);
-       setenv1("SCRIPT_FILENAME", fullpath);
+       /* SCRIPT_FILENAME is required by PHP in CGI mode */
+       if (home_httpd[0] == '/') {
+               char *fullpath = concat_path_file(home_httpd, url);
+               setenv1("SCRIPT_FILENAME", fullpath);
+       }
        /* set SCRIPT_NAME as full path: /cgi-bin/dirs/script.cgi */
-       setenv1("SCRIPT_NAME", purl);
+       setenv1("SCRIPT_NAME", url);
        /* http://hoohoo.ncsa.uiuc.edu/cgi/env.html:
         * QUERY_STRING: The information which follows the ? in the URL
         * which referenced this script. This is the query information.
@@ -1025,8 +1393,12 @@ static void send_cgi_and_exit(
                }
        }
        setenv1("HTTP_USER_AGENT", user_agent);
-       if (bodyLen)
-               putenv(xasprintf("CONTENT_LENGTH=%d", bodyLen));
+       if (http_accept)
+               setenv1("HTTP_ACCEPT", http_accept);
+       if (http_accept_language)
+               setenv1("HTTP_ACCEPT_LANGUAGE", http_accept_language);
+       if (post_len)
+               putenv(xasprintf("CONTENT_LENGTH=%d", post_len));
        if (cookie)
                setenv1("HTTP_COOKIE", cookie);
        if (content_type)
@@ -1039,9 +1411,12 @@ static void send_cgi_and_exit(
 #endif
        if (referer)
                setenv1("HTTP_REFERER", referer);
+       setenv1("HTTP_HOST", host); /* set to "" if NULL */
+       /* setenv1("SERVER_NAME", safe_gethostname()); - don't do this,
+        * just run "env SERVER_NAME=xyz httpd ..." instead */
 
-       xpipe(&fromCgi.rd);
-       xpipe(&toCgi.rd);
+       xpiped_pair(fromCgi);
+       xpiped_pair(toCgi);
 
        pid = vfork();
        if (pid < 0) {
@@ -1051,49 +1426,66 @@ static void send_cgi_and_exit(
 
        if (!pid) {
                /* Child process */
+               char *argv[3];
+
                xfunc_error_retval = 242;
 
+               /* NB: close _first_, then move fds! */
+               close(toCgi.wr);
+               close(fromCgi.rd);
                xmove_fd(toCgi.rd, 0);  /* replace stdin with the pipe */
                xmove_fd(fromCgi.wr, 1);  /* replace stdout with the pipe */
-               close(fromCgi.rd);
-               close(toCgi.wr);
                /* User seeing stderr output can be a security problem.
                 * If CGI really wants that, it can always do dup itself. */
                /* dup2(1, 2); */
 
-               /* script must have absolute path */
-               script = strrchr(fullpath, '/');
-               if (!script)
-                       goto error_execing_cgi;
-               *script = '\0';
-               /* chdiring to script's dir */
-               if (chdir(fullpath) == 0) {
-                       char *argv[2];
+               /* Chdiring to script's dir */
+               script = strrchr(url, '/');
+               if (script != url) { /* paranoia */
+                       *script = '\0';
+                       if (chdir(url + 1) != 0) {
+                               bb_perror_msg("chdir(%s)", url + 1);
+                               goto error_execing_cgi;
+                       }
+                       // not needed: *script = '/';
+               }
+               script++;
+
+               /* set argv[0] to name without path */
+               argv[0] = script;
+               argv[1] = NULL;
+
 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
-                       char *interpr = NULL;
-                       char *suffix = strrchr(purl, '.');
+               {
+                       char *suffix = strrchr(script, '.');
 
                        if (suffix) {
                                Htaccess *cur;
                                for (cur = script_i; cur; cur = cur->next) {
                                        if (strcmp(cur->before_colon + 1, suffix) == 0) {
-                                               interpr = cur->after_colon;
+                                               /* found interpreter name */
+                                               argv[0] = cur->after_colon;
+                                               argv[1] = script;
+                                               argv[2] = NULL;
                                                break;
                                        }
                                }
                        }
-#endif
-                       *script = '/';
-                       /* set argv[0] to name without path */
-                       argv[0] = (char*)bb_basename(purl);
-                       argv[1] = NULL;
-#if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
-                       if (interpr)
-                               execv(interpr, argv);
-                       else
-#endif
-                               execv(fullpath, argv);
                }
+#endif
+               /* restore default signal dispositions for CGI process */
+               bb_signals(0
+                       | (1 << SIGCHLD)
+                       | (1 << SIGPIPE)
+                       | (1 << SIGHUP)
+                       , SIG_DFL);
+
+               /* _NOT_ execvp. We do not search PATH. argv[0] is a filename
+                * without any dir components and will only match a file
+                * in the current directory */
+               execv(argv[0], argv);
+               if (verbose)
+                       bb_perror_msg("can't execute '%s'", argv[0]);
  error_execing_cgi:
                /* send to stdout
                 * (we are CGI here, our stdout is pumped to the net) */
@@ -1102,277 +1494,187 @@ static void send_cgi_and_exit(
 
        /* Parent process */
 
-       /* First, restore variables possibly changed by child */
+       /* Restore variables possibly changed by child */
        xfunc_error_retval = 0;
 
-       /* Prepare for pumping data.
-        * iobuf is used for CGI -> network data,
-        * hdr_buf is for network -> CGI data (POSTDATA) */
-       buf_count = 0;
+       /* Pump data */
        close(fromCgi.wr);
        close(toCgi.rd);
-
-       /* If CGI dies, we still want to correctly finish reading its output
-        * and send it to the peer. So please no SIGPIPEs! */
-       signal(SIGPIPE, SIG_IGN);
-
-       /* This loop still looks messy. What is an exit criteria?
-        * "CGI's output closed"? Or "CGI has exited"?
-        * What to do if CGI has closed both input and output, but
-        * didn't exit? etc... */
-
-       /* NB: breaking out of this loop jumps to log_and_exit() */
-       while (1) {
-               fd_set readSet;
-               fd_set writeSet;
-               int nfound;
-               int count;
-
-               FD_ZERO(&readSet);
-               FD_ZERO(&writeSet);
-               FD_SET(fromCgi.rd, &readSet);
-               if (bodyLen > 0 || hdr_cnt > 0) {
-                       FD_SET(toCgi.wr, &writeSet);
-                       nfound = toCgi.wr > fromCgi.rd ? toCgi.wr : fromCgi.rd;
-                       if (hdr_cnt <= 0)
-                               FD_SET(0, &readSet);
-                       /* Now wait on the set of sockets! */
-                       nfound = select(nfound + 1, &readSet, &writeSet, NULL, NULL);
-               } else {
-                       if (!bodyLen) {
-                               close(toCgi.wr); /* no more POST data to CGI */
-                               bodyLen = -1;
-                       }
-                       nfound = select(fromCgi.rd + 1, &readSet, NULL, NULL, NULL);
-               }
-
-               if (nfound <= 0) {
-                       if (waitpid(pid, &status, WNOHANG) <= 0) {
-                               /* Weird. CGI didn't exit and no fd's
-                                * are ready, yet select returned?! */
-                               continue;
-                       }
-                       close(fromCgi.rd);
-                       if (DEBUG && WIFEXITED(status))
-                               bb_error_msg("CGI exited, status=%d", WEXITSTATUS(status));
-                       if (DEBUG && WIFSIGNALED(status))
-                               bb_error_msg("CGI killed, signal=%d", WTERMSIG(status));
-                       break;
-               }
-
-               if (hdr_cnt > 0 && FD_ISSET(toCgi.wr, &writeSet)) {
-                       /* Have data from peer and can write to CGI */
-                       count = safe_write(toCgi.wr, hdr_ptr, hdr_cnt);
-                       /* Doesn't happen, we dont use nonblocking IO here
-                        *if (count < 0 && errno == EAGAIN) {
-                        *      ...
-                        *} else */
-                       if (count > 0) {
-                               hdr_ptr += count;
-                               hdr_cnt -= count;
-                       } else {
-                               hdr_cnt = bodyLen = 0; /* EOF/broken pipe to CGI */
-                       }
-               } else if (bodyLen > 0 && hdr_cnt == 0
-                && FD_ISSET(0, &readSet)
-               ) {
-                       /* We expect data, prev data portion is eaten by CGI
-                        * and there *is* data to read from the peer
-                        * (POSTDATA?) */
-                       count = bodyLen > (int)sizeof(hdr_buf) ? (int)sizeof(hdr_buf) : bodyLen;
-                       count = safe_read(0, hdr_buf, count);
-                       if (count > 0) {
-                               hdr_cnt = count;
-                               hdr_ptr = hdr_buf;
-                               bodyLen -= count;
-                       } else {
-                               bodyLen = 0; /* closed */
-                       }
-               }
-
-#define PIPESIZE PIPE_BUF
-#if PIPESIZE >= IOBUF_SIZE
-# error "PIPESIZE >= IOBUF_SIZE"
-#endif
-               if (FD_ISSET(fromCgi.rd, &readSet)) {
-                       /* There is something to read from CGI */
-                       char *rbuf = iobuf;
-
-                       /* Are we still buffering CGI output? */
-                       if (buf_count >= 0) {
-                               /* HTTP_200[] has single "\r\n" at the end.
-                                * According to http://hoohoo.ncsa.uiuc.edu/cgi/out.html,
-                                * CGI scripts MUST send their own header terminated by
-                                * empty line, then data. That's why we have only one
-                                * <cr><lf> pair here. We will output "200 OK" line
-                                * if needed, but CGI still has to provide blank line
-                                * between header and body */
-
-                               /* Must use safe_read, not full_read, because
-                                * CGI may output a few first bytes and then wait
-                                * for POSTDATA without closing stdout.
-                                * With full_read we may wait here forever. */
-                               count = safe_read(fromCgi.rd, rbuf + buf_count, PIPESIZE - 8);
-                               if (count <= 0) {
-                                       /* eof (or error) and there was no "HTTP",
-                                        * so write it, then write received data */
-                                       if (buf_count) {
-                                               full_write(1, HTTP_200, sizeof(HTTP_200)-1);
-                                               full_write(1, rbuf, buf_count);
-                                       }
-                                       break; /* CGI stdout is closed, exiting */
-                               }
-                               buf_count += count;
-                               count = 0;
-                               /* "Status" header format is: "Status: 302 Redirected\r\n" */
-                               if (buf_count >= 8 && memcmp(rbuf, "Status: ", 8) == 0) {
-                                       /* send "HTTP/1.0 " */
-                                       if (full_write(1, HTTP_200, 9) != 9)
-                                               break;
-                                       rbuf += 8; /* skip "Status: " */
-                                       count = buf_count - 8;
-                                       buf_count = -1; /* buffering off */
-                               } else if (buf_count >= 4) {
-                                       /* Did CGI add "HTTP"? */
-                                       if (memcmp(rbuf, HTTP_200, 4) != 0) {
-                                               /* there is no "HTTP", do it ourself */
-                                               if (full_write(1, HTTP_200, sizeof(HTTP_200)-1) != sizeof(HTTP_200)-1)
-                                                       break;
-                                       }
-                                       /* Commented out:
-                                       if (!strstr(rbuf, "ontent-")) {
-                                               full_write(s, "Content-type: text/plain\r\n\r\n", 28);
-                                       }
-                                        * Counter-example of valid CGI without Content-type:
-                                        * echo -en "HTTP/1.0 302 Found\r\n"
-                                        * echo -en "Location: http://www.busybox.net\r\n"
-                                        * echo -en "\r\n"
-                                        */
-                                       count = buf_count;
-                                       buf_count = -1; /* buffering off */
-                               }
-                       } else {
-                               count = safe_read(fromCgi.rd, rbuf, PIPESIZE);
-                               if (count <= 0)
-                                       break;  /* eof (or error) */
-                       }
-                       if (full_write(1, rbuf, count) != count)
-                               break;
-                       if (DEBUG)
-                               fprintf(stderr, "cgi read %d bytes: '%.*s'\n", count, count, rbuf);
-               } /* if (FD_ISSET(fromCgi.rd)) */
-       } /* while (1) */
-       log_and_exit();
+       cgi_io_loop_and_exit(fromCgi.rd, toCgi.wr, post_len);
 }
+
 #endif          /* FEATURE_HTTPD_CGI */
 
 /*
  * Send a file response to a HTTP request, and exit
+ *
+ * Parameters:
+ * const char *url  The requested URL (with leading /).
+ * what             What to send (headers/body/both).
  */
-static void send_file_and_exit(const char *url) ATTRIBUTE_NORETURN;
-static void send_file_and_exit(const char *url)
+static NOINLINE void send_file_and_exit(const char *url, int what)
 {
-       static const char *const suffixTable[] = {
-       /* Warning: shorter equivalent suffix in one line must be first */
-               ".htm.html", "text/html",
-               ".jpg.jpeg", "image/jpeg",
-               ".gif",      "image/gif",
-               ".png",      "image/png",
-               ".txt.h.c.cc.cpp", "text/plain",
-               ".css",      "text/css",
-               ".wav",      "audio/wav",
-               ".avi",      "video/x-msvideo",
-               ".qt.mov",   "video/quicktime",
-               ".mpe.mpeg", "video/mpeg",
-               ".mid.midi", "audio/midi",
-               ".mp3",      "audio/mpeg",
-#if 0                        /* unpopular */
-               ".au",       "audio/basic",
-               ".pac",      "application/x-ns-proxy-autoconfig",
-               ".vrml.wrl", "model/vrml",
-#endif
-               NULL
-       };
-
        char *suffix;
-       int f;
-       const char *const *table;
-       const char *try_suffix;
+       int fd;
        ssize_t count;
-#if ENABLE_FEATURE_HTTPD_USE_SENDFILE
-       off_t offset = 0;
-#endif
 
-       suffix = strrchr(url, '.');
+       if (content_gzip) {
+               /* does <url>.gz exist? Then use it instead */
+               char *gzurl = xasprintf("%s.gz", url);
+               fd = open(gzurl, O_RDONLY);
+               free(gzurl);
+               if (fd != -1) {
+                       struct stat sb;
+                       fstat(fd, &sb);
+                       file_size = sb.st_size;
+                       last_mod = sb.st_mtime;
+               } else {
+                       IF_FEATURE_HTTPD_GZIP(content_gzip = 0;)
+                       fd = open(url, O_RDONLY);
+               }
+       } else {
+               fd = open(url, O_RDONLY);
+       }
+       if (fd < 0) {
+               if (DEBUG)
+                       bb_perror_msg("can't open '%s'", url);
+               /* Error pages are sent by using send_file_and_exit(SEND_BODY).
+                * IOW: it is unsafe to call send_headers_and_exit
+                * if what is SEND_BODY! Can recurse! */
+               if (what != SEND_BODY)
+                       send_headers_and_exit(HTTP_NOT_FOUND);
+               log_and_exit();
+       }
+       /* If you want to know about EPIPE below
+        * (happens if you abort downloads from local httpd): */
+       signal(SIGPIPE, SIG_IGN);
 
-       /* If not found, set default as "application/octet-stream";  */
+       /* If not found, default is "application/octet-stream" */
        found_mime_type = "application/octet-stream";
+       suffix = strrchr(url, '.');
        if (suffix) {
-#if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
-               Htaccess *cur;
+               static const char suffixTable[] ALIGN1 =
+                       /* Shorter suffix must be first:
+                        * ".html.htm" will fail for ".htm"
+                        */
+                       ".txt.h.c.cc.cpp\0" "text/plain\0"
+                       /* .htm line must be after .h line */
+                       ".htm.html\0" "text/html\0"
+                       ".jpg.jpeg\0" "image/jpeg\0"
+                       ".gif\0"      "image/gif\0"
+                       ".png\0"      "image/png\0"
+                       /* .css line must be after .c line */
+                       ".css\0"      "text/css\0"
+                       ".wav\0"      "audio/wav\0"
+                       ".avi\0"      "video/x-msvideo\0"
+                       ".qt.mov\0"   "video/quicktime\0"
+                       ".mpe.mpeg\0" "video/mpeg\0"
+                       ".mid.midi\0" "audio/midi\0"
+                       ".mp3\0"      "audio/mpeg\0"
+#if 0  /* unpopular */
+                       ".au\0"       "audio/basic\0"
+                       ".pac\0"      "application/x-ns-proxy-autoconfig\0"
+                       ".vrml.wrl\0" "model/vrml\0"
 #endif
-               for (table = suffixTable; *table; table += 2) {
-                       try_suffix = strstr(table[0], suffix);
-                       if (try_suffix) {
-                               try_suffix += strlen(suffix);
-                               if (*try_suffix == '\0' || *try_suffix == '.') {
-                                       found_mime_type = table[1];
-                                       break;
-                               }
+                       /* compiler adds another "\0" here */
+               ;
+               Htaccess *cur;
+
+               /* Examine built-in table */
+               const char *table = suffixTable;
+               const char *table_next;
+               for (; *table; table = table_next) {
+                       const char *try_suffix;
+                       const char *mime_type;
+                       mime_type  = table + strlen(table) + 1;
+                       table_next = mime_type + strlen(mime_type) + 1;
+                       try_suffix = strstr(table, suffix);
+                       if (!try_suffix)
+                               continue;
+                       try_suffix += strlen(suffix);
+                       if (*try_suffix == '\0' || *try_suffix == '.') {
+                               found_mime_type = mime_type;
+                               break;
                        }
+                       /* Example: strstr(table, ".av") != NULL, but it
+                        * does not match ".avi" after all and we end up here.
+                        * The table is arranged so that in this case we know
+                        * that it can't match anything in the following lines,
+                        * and we stop the search: */
+                       break;
                }
-#if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
+               /* ...then user's table */
                for (cur = mime_a; cur; cur = cur->next) {
                        if (strcmp(cur->before_colon, suffix) == 0) {
                                found_mime_type = cur->after_colon;
                                break;
                        }
                }
-#endif
        }
 
        if (DEBUG)
                bb_error_msg("sending file '%s' content-type: %s",
                        url, found_mime_type);
 
-       f = open(url, O_RDONLY);
-       if (f < 0) {
-               if (DEBUG)
-                       bb_perror_msg("cannot open '%s'", url);
-               send_headers_and_exit(HTTP_NOT_FOUND);
+#if ENABLE_FEATURE_HTTPD_RANGES
+       if (what == SEND_BODY /* err pages and ranges don't mix */
+        || content_gzip /* we are sending compressed page: can't do ranges */  ///why?
+       ) {
+               range_start = 0;
        }
-
-       send_headers(HTTP_OK);
-
-       /* If you want to know about EPIPE below
-        * (happens if you abort downloads from local httpd): */
-       signal(SIGPIPE, SIG_IGN);
-
+       range_len = MAXINT(off_t);
+       if (range_start) {
+               if (!range_end) {
+                       range_end = file_size - 1;
+               }
+               if (range_end < range_start
+                || lseek(fd, range_start, SEEK_SET) != range_start
+               ) {
+                       lseek(fd, 0, SEEK_SET);
+                       range_start = 0;
+               } else {
+                       range_len = range_end - range_start + 1;
+                       send_headers(HTTP_PARTIAL_CONTENT);
+                       what = SEND_BODY;
+               }
+       }
+#endif
+       if (what & SEND_HEADERS)
+               send_headers(HTTP_OK);
 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
-       do {
-               /* byte count (3rd arg) is rounded down to 64k */
-               count = sendfile(1, f, &offset, MAXINT(ssize_t) - 0xffff);
-               if (count < 0) {
-                       if (offset == 0)
-                               goto fallback;
-                       goto fin;
+       {
+               off_t offset = range_start;
+               while (1) {
+                       /* sz is rounded down to 64k */
+                       ssize_t sz = MAXINT(ssize_t) - 0xffff;
+                       IF_FEATURE_HTTPD_RANGES(if (sz > range_len) sz = range_len;)
+                       count = sendfile(STDOUT_FILENO, fd, &offset, sz);
+                       if (count < 0) {
+                               if (offset == range_start)
+                                       break; /* fall back to read/write loop */
+                               goto fin;
+                       }
+                       IF_FEATURE_HTTPD_RANGES(range_len -= sz;)
+                       if (count == 0 || range_len == 0)
+                               log_and_exit();
                }
-       } while (count > 0);
-       log_and_exit();
-
- fallback:
+       }
 #endif
-       while ((count = safe_read(f, iobuf, IOBUF_SIZE)) > 0) {
-               ssize_t n = count;
-               count = full_write(1, iobuf, count);
+       while ((count = safe_read(fd, iobuf, IOBUF_SIZE)) > 0) {
+               ssize_t n;
+               IF_FEATURE_HTTPD_RANGES(if (count > range_len) count = range_len;)
+               n = full_write(STDOUT_FILENO, iobuf, count);
                if (count != n)
                        break;
+               IF_FEATURE_HTTPD_RANGES(range_len -= count;)
+               if (range_len == 0)
+                       break;
+       }
+       if (count < 0) {
+ IF_FEATURE_HTTPD_USE_SENDFILE(fin:)
+               if (verbose > 1)
+                       bb_perror_msg("error");
        }
-#if ENABLE_FEATURE_HTTPD_USE_SENDFILE
- fin:
-#endif
-       if (count < 0 && verbose > 1)
-               bb_perror_msg("error");
        log_and_exit();
 }
 
@@ -1380,7 +1682,6 @@ static int checkPermIP(void)
 {
        Htaccess_IP *cur;
 
-       /* This could stand some work */
        for (cur = ip_a_d; cur; cur = cur->next) {
 #if DEBUG
                fprintf(stderr,
@@ -1397,99 +1698,112 @@ static int checkPermIP(void)
                );
 #endif
                if ((rmt_ip & cur->mask) == cur->ip)
-                       return cur->allow_deny == 'A';   /* Allow/Deny */
+                       return (cur->allow_deny == 'A'); /* A -> 1 */
        }
 
-       /* if unconfigured, return 1 - access from all */
-       return !flg_deny_all;
+       return !flg_deny_all; /* depends on whether we saw "D:*" */
 }
 
 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 /*
- * Check the permission file for access password protected.
- *
- * If config file isn't present, everything is allowed.
- * Entries are of the form you can see example from header source
+ * Config file entries are of the form "/<path>:<user>:<passwd>".
+ * If config file has no prefix match for path, access is allowed.
  *
- * path      The file path.
- * request   User information to validate.
+ * path                 The file path
+ * user_and_passwd      "user:passwd" to validate
  *
- * Returns 1 if request is OK.
+ * Returns 1 if user_and_passwd is OK.
  */
-static int checkPerm(const char *path, const char *request)
+static int check_user_passwd(const char *path, const char *user_and_passwd)
 {
        Htaccess *cur;
-       const char *p;
-       const char *p0;
-
        const char *prev = NULL;
 
-       /* This could stand some work */
        for (cur = g_auth; cur; cur = cur->next) {
-               size_t l;
+               const char *dir_prefix;
+               size_t len;
+
+               dir_prefix = cur->before_colon;
+
+               /* WHY? */
+               /* If already saw a match, don't accept other different matches */
+               if (prev && strcmp(prev, dir_prefix) != 0)
+                       continue;
 
-               p0 = cur->before_colon;
-               if (prev != NULL && strcmp(prev, p0) != 0)
-                       continue;       /* find next identical */
-               p = cur->after_colon;
                if (DEBUG)
-                       fprintf(stderr, "checkPerm: '%s' ? '%s'\n", p0, request);
+                       fprintf(stderr, "checkPerm: '%s' ? '%s'\n", dir_prefix, user_and_passwd);
 
-               l = strlen(p0);
-               if (strncmp(p0, path, l) == 0
-                && (l == 1 || path[l] == '/' || path[l] == '\0')
+               /* If it's not a prefix match, continue searching */
+               len = strlen(dir_prefix);
+               if (len != 1 /* dir_prefix "/" matches all, don't need to check */
+                && (strncmp(dir_prefix, path, len) != 0
+                   || (path[len] != '/' && path[len] != '\0'))
                ) {
-                       char *u;
-                       /* path match found.  Check request */
-                       /* for check next /path:user:password */
-                       prev = p0;
-                       u = strchr(request, ':');
-                       if (u == NULL) {
-                               /* bad request, ':' required */
-                               break;
-                       }
+                       continue;
+               }
 
-                       if (ENABLE_FEATURE_HTTPD_AUTH_MD5) {
-                               char *cipher;
-                               char *pp;
+               /* Path match found */
+               prev = dir_prefix;
 
-                               if (strncmp(p, request, u - request) != 0) {
-                                       /* user doesn't match */
-                                       continue;
-                               }
-                               pp = strchr(p, ':');
-                               if (pp && pp[1] == '$' && pp[2] == '1'
-                                && pp[3] == '$' && pp[4]
-                               ) {
-                                       pp++;
-                                       cipher = pw_encrypt(u+1, pp);
-                                       if (strcmp(cipher, pp) == 0)
-                                               goto set_remoteuser_var;   /* Ok */
-                                       /* unauthorized */
+               if (ENABLE_FEATURE_HTTPD_AUTH_MD5) {
+                       char *md5_passwd;
+
+                       md5_passwd = strchr(cur->after_colon, ':');
+                       if (md5_passwd && md5_passwd[1] == '$' && md5_passwd[2] == '1'
+                        && md5_passwd[3] == '$' && md5_passwd[4]
+                       ) {
+                               char *encrypted;
+                               int r, user_len_p1;
+
+                               md5_passwd++;
+                               user_len_p1 = md5_passwd - cur->after_colon;
+                               /* comparing "user:" */
+                               if (strncmp(cur->after_colon, user_and_passwd, user_len_p1) != 0) {
                                        continue;
                                }
+
+                               encrypted = pw_encrypt(
+                                       user_and_passwd + user_len_p1 /* cleartext pwd from user */,
+                                       md5_passwd /*salt */, 1 /* cleanup */);
+                               r = strcmp(encrypted, md5_passwd);
+                               free(encrypted);
+                               if (r == 0)
+                                       goto set_remoteuser_var; /* Ok */
+                               continue;
                        }
+               }
 
-                       if (strcmp(p, request) == 0) {
+               /* Comparing plaintext "user:pass" in one go */
+               if (strcmp(cur->after_colon, user_and_passwd) == 0) {
  set_remoteuser_var:
-                               remoteuser = strdup(request);
-                               if (remoteuser)
-                                       remoteuser[u - request] = '\0';
-                               return 1;   /* Ok */
-                       }
-                       /* unauthorized */
+                       remoteuser = xstrndup(user_and_passwd,
+                                       strchrnul(user_and_passwd, ':') - user_and_passwd);
+                       return 1; /* Ok */
                }
        } /* for */
 
-       return prev == NULL;
+       /* 0(bad) if prev is set: matches were found but passwd was wrong */
+       return (prev == NULL);
 }
 #endif  /* FEATURE_HTTPD_BASIC_AUTH */
 
+#if ENABLE_FEATURE_HTTPD_PROXY
+static Htaccess_Proxy *find_proxy_entry(const char *url)
+{
+       Htaccess_Proxy *p;
+       for (p = proxy; p; p = p->next) {
+               if (strncmp(url, p->url_from, strlen(p->url_from)) == 0)
+                       return p;
+       }
+       return NULL;
+}
+#endif
+
 /*
  * Handle timeouts
  */
-static void exit_on_signal(int sig) ATTRIBUTE_NORETURN;
-static void exit_on_signal(int sig)
+static void send_REQUEST_TIMEOUT_and_exit(int sig) NORETURN;
+static void send_REQUEST_TIMEOUT_and_exit(int sig UNUSED_PARAM)
 {
        send_headers_and_exit(HTTP_REQUEST_TIMEOUT);
 }
@@ -1497,26 +1811,34 @@ static void exit_on_signal(int sig)
 /*
  * Handle an incoming http request and exit.
  */
-static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) ATTRIBUTE_NORETURN;
+static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) NORETURN;
 static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
 {
        static const char request_GET[] ALIGN1 = "GET";
-
        struct stat sb;
        char *urlcopy;
        char *urlp;
        char *tptr;
-       int http_major_version;
-       int ip_allowed;
 #if ENABLE_FEATURE_HTTPD_CGI
+       static const char request_HEAD[] ALIGN1 = "HEAD";
        const char *prequest;
+       char *cookie = NULL;
+       char *content_type = NULL;
+       unsigned long length = 0;
+#elif ENABLE_FEATURE_HTTPD_PROXY
+#define prequest request_GET
        unsigned long length = 0;
-       char *cookie = 0;
-       char *content_type = 0;
 #endif
-       struct sigaction sa;
 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
-       int credentials = -1;  /* if not required this is Ok */
+       smallint authorized = -1;
+#endif
+       smallint ip_allowed;
+       char http_major_version;
+#if ENABLE_FEATURE_HTTPD_PROXY
+       char http_minor_version;
+       char *header_buf = header_buf; /* for gcc */
+       char *header_ptr = header_ptr;
+       Htaccess_Proxy *proxy_entry;
 #endif
 
        /* Allocation of iobuf is postponed until now
@@ -1524,26 +1846,30 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
        iobuf = xmalloc(IOBUF_SIZE);
 
        rmt_ip = 0;
-       if (fromAddr->sa.sa_family == AF_INET) {
-               rmt_ip = ntohl(fromAddr->sin.sin_addr.s_addr);
+       if (fromAddr->u.sa.sa_family == AF_INET) {
+               rmt_ip = ntohl(fromAddr->u.sin.sin_addr.s_addr);
        }
+#if ENABLE_FEATURE_IPV6
+       if (fromAddr->u.sa.sa_family == AF_INET6
+        && fromAddr->u.sin6.sin6_addr.s6_addr32[0] == 0
+        && fromAddr->u.sin6.sin6_addr.s6_addr32[1] == 0
+        && ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[2]) == 0xffff)
+               rmt_ip = ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[3]);
+#endif
        if (ENABLE_FEATURE_HTTPD_CGI || DEBUG || verbose) {
-               rmt_ip_str = xmalloc_sockaddr2dotted(&fromAddr->sa);
+               /* NB: can be NULL (user runs httpd -i by hand?) */
+               rmt_ip_str = xmalloc_sockaddr2dotted(&fromAddr->u.sa);
        }
        if (verbose) {
                /* this trick makes -v logging much simpler */
-               applet_name = rmt_ip_str;
+               if (rmt_ip_str)
+                       applet_name = rmt_ip_str;
                if (verbose > 2)
                        bb_error_msg("connected");
        }
 
-       /* Install timeout handler */
-       memset(&sa, 0, sizeof(sa));
-       sa.sa_handler = exit_on_signal;
-       /* sigemptyset(&sa.sa_mask); - memset should be enough */
-       /*sa.sa_flags = 0; - no SA_RESTART */
-       sigaction(SIGALRM, &sa, NULL);
-       alarm(HEADER_READ_TIMEOUT);
+       /* Install timeout handler. get_line() needs it. */
+       signal(SIGALRM, send_REQUEST_TIMEOUT_and_exit);
 
        if (!get_line()) /* EOF or error or empty line */
                send_headers_and_exit(HTTP_BAD_REQUEST);
@@ -1556,9 +1882,12 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
 #if ENABLE_FEATURE_HTTPD_CGI
        prequest = request_GET;
        if (strcasecmp(iobuf, prequest) != 0) {
-               prequest = "POST";
-               if (strcasecmp(iobuf, prequest) != 0)
-                       send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
+               prequest = request_HEAD;
+               if (strcasecmp(iobuf, prequest) != 0) {
+                       prequest = "POST";
+                       if (strcasecmp(iobuf, prequest) != 0)
+                               send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
+               }
        }
 #else
        if (strcasecmp(iobuf, request_GET) != 0)
@@ -1569,23 +1898,26 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
                send_headers_and_exit(HTTP_BAD_REQUEST);
 
        /* Find end of URL and parse HTTP version, if any */
-       http_major_version = -1;
+       http_major_version = '0';
+       IF_FEATURE_HTTPD_PROXY(http_minor_version = '0';)
        tptr = strchrnul(urlp, ' ');
        /* Is it " HTTP/"? */
-       if (tptr[0] && strncmp(tptr + 1, HTTP_200, 5) == 0)
-               http_major_version = (tptr[6] - '0');
+       if (tptr[0] && strncmp(tptr + 1, HTTP_200, 5) == 0) {
+               http_major_version = tptr[6];
+               IF_FEATURE_HTTPD_PROXY(http_minor_version = tptr[8];)
+       }
        *tptr = '\0';
 
        /* Copy URL from after "GET "/"POST " to stack-allocated char[] */
-       urlcopy = alloca((tptr - urlp) + sizeof("/index.html"));
+       urlcopy = alloca((tptr - urlp) + 2 + strlen(index_page));
        /*if (urlcopy == NULL)
         *      send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);*/
        strcpy(urlcopy, urlp);
        /* NB: urlcopy ptr is never changed after this */
 
        /* Extract url args if present */
-       tptr = strchr(urlcopy, '?');
        g_query = NULL;
+       tptr = strchr(urlcopy, '?');
        if (tptr) {
                *tptr++ = '\0';
                g_query = tptr;
@@ -1602,7 +1934,7 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
 
        /* Canonicalize path */
        /* Algorithm stolen from libbb bb_simplify_path(),
-        * but don't strdup and reducing trailing slash and protect out root */
+        * but don't strdup, retain trailing slash, protect root */
        urlp = tptr = urlcopy;
        do {
                if (*urlp == '/') {
@@ -1611,11 +1943,11 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
                                continue;
                        }
                        if (*tptr == '.') {
-                               /* skip extra '.' */
+                               /* skip extra "/./" */
                                if (tptr[1] == '/' || !tptr[1]) {
                                        continue;
                                }
-                               /* '..': be careful */
+                               /* "..": be careful */
                                if (tptr[1] == '.' && (tptr[2] == '/' || !tptr[2])) {
                                        ++tptr;
                                        if (urlp == urlcopy) /* protect root */
@@ -1627,12 +1959,11 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
                }
                *++urlp = *tptr;
        } while (*++tptr);
-       *++urlp = '\0';       /* so keep last character */
-       tptr = urlp;          /* end ptr */
+       *++urlp = '\0';       /* terminate after last character */
 
        /* If URL is a directory, add '/' */
-       if (tptr[-1] != '/') {
-               if (is_directory(urlcopy + 1, 1, &sb)) {
+       if (urlp[-1] != '/') {
+               if (is_directory(urlcopy + 1, 1, NULL)) {
                        found_moved_temporarily = urlcopy;
                }
        }
@@ -1646,56 +1977,87 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
        while (ip_allowed && (tptr = strchr(tptr + 1, '/')) != NULL) {
                /* have path1/path2 */
                *tptr = '\0';
-               if (is_directory(urlcopy + 1, 1, &sb)) {
-                       /* may be having subdir config */
+               if (is_directory(urlcopy + 1, 1, NULL)) {
+                       /* may have subdir config */
                        parse_conf(urlcopy + 1, SUBDIR_PARSE);
                        ip_allowed = checkPermIP();
                }
                *tptr = '/';
        }
-       if (http_major_version >= 0) {
+
+#if ENABLE_FEATURE_HTTPD_PROXY
+       proxy_entry = find_proxy_entry(urlcopy);
+       if (proxy_entry)
+               header_buf = header_ptr = xmalloc(IOBUF_SIZE);
+#endif
+
+       if (http_major_version >= '0') {
                /* Request was with "... HTTP/nXXX", and n >= 0 */
 
-               /* Read until blank line for HTTP version specified, else parse immediate */
+               /* Read until blank line */
                while (1) {
-                       alarm(HEADER_READ_TIMEOUT);
                        if (!get_line())
                                break; /* EOF or error or empty line */
                        if (DEBUG)
                                bb_error_msg("header: '%s'", iobuf);
 
-#if ENABLE_FEATURE_HTTPD_CGI
-                       /* try and do our best to parse more lines */
+#if ENABLE_FEATURE_HTTPD_PROXY
+                       /* We need 2 more bytes for yet another "\r\n" -
+                        * see near fdprintf(proxy_fd...) further below */
+                       if (proxy_entry && (header_ptr - header_buf) < IOBUF_SIZE - 2) {
+                               int len = strlen(iobuf);
+                               if (len > IOBUF_SIZE - (header_ptr - header_buf) - 4)
+                                       len = IOBUF_SIZE - (header_ptr - header_buf) - 4;
+                               memcpy(header_ptr, iobuf, len);
+                               header_ptr += len;
+                               header_ptr[0] = '\r';
+                               header_ptr[1] = '\n';
+                               header_ptr += 2;
+                       }
+#endif
+
+#if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
+                       /* Try and do our best to parse more lines */
                        if ((STRNCASECMP(iobuf, "Content-length:") == 0)) {
                                /* extra read only for POST */
-                               if (prequest != request_GET) {
-                                       tptr = iobuf + sizeof("Content-length:") - 1;
+                               if (prequest != request_GET
+# if ENABLE_FEATURE_HTTPD_CGI
+                                && prequest != request_HEAD
+# endif
+                               ) {
+                                       tptr = skip_whitespace(iobuf + sizeof("Content-length:") - 1);
                                        if (!tptr[0])
                                                send_headers_and_exit(HTTP_BAD_REQUEST);
-                                       errno = 0;
                                        /* not using strtoul: it ignores leading minus! */
-                                       length = strtol(tptr, &tptr, 10);
+                                       length = bb_strtou(tptr, NULL, 10);
                                        /* length is "ulong", but we need to pass it to int later */
-                                       /* so we check for negative or too large values in one go: */
-                                       /* (long -> ulong conv caused negatives to be seen as > INT_MAX) */
-                                       if (tptr[0] || errno || length > INT_MAX)
+                                       if (errno || length > INT_MAX)
                                                send_headers_and_exit(HTTP_BAD_REQUEST);
                                }
-                       } else if (STRNCASECMP(iobuf, "Cookie:") == 0) {
-                               cookie = strdup(skip_whitespace(iobuf + sizeof("Cookie:")-1));
+                       }
+#endif
+#if ENABLE_FEATURE_HTTPD_CGI
+                       else if (STRNCASECMP(iobuf, "Cookie:") == 0) {
+                               cookie = xstrdup(skip_whitespace(iobuf + sizeof("Cookie:")-1));
                        } else if (STRNCASECMP(iobuf, "Content-Type:") == 0) {
-                               content_type = strdup(skip_whitespace(iobuf + sizeof("Content-Type:")-1));
+                               content_type = xstrdup(skip_whitespace(iobuf + sizeof("Content-Type:")-1));
                        } else if (STRNCASECMP(iobuf, "Referer:") == 0) {
-                               referer = strdup(skip_whitespace(iobuf + sizeof("Referer:")-1));
+                               referer = xstrdup(skip_whitespace(iobuf + sizeof("Referer:")-1));
                        } else if (STRNCASECMP(iobuf, "User-Agent:") == 0) {
-                               user_agent = strdup(skip_whitespace(iobuf + sizeof("User-Agent:")-1));
+                               user_agent = xstrdup(skip_whitespace(iobuf + sizeof("User-Agent:")-1));
+                       } else if (STRNCASECMP(iobuf, "Host:") == 0) {
+                               host = xstrdup(skip_whitespace(iobuf + sizeof("Host:")-1));
+                       } else if (STRNCASECMP(iobuf, "Accept:") == 0) {
+                               http_accept = xstrdup(skip_whitespace(iobuf + sizeof("Accept:")-1));
+                       } else if (STRNCASECMP(iobuf, "Accept-Language:") == 0) {
+                               http_accept_language = xstrdup(skip_whitespace(iobuf + sizeof("Accept-Language:")-1));
                        }
 #endif
 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
                        if (STRNCASECMP(iobuf, "Authorization:") == 0) {
                                /* We only allow Basic credentials.
-                                * It shows up as "Authorization: Basic <userid:password>" where
-                                * the userid:password is base64 encoded.
+                                * It shows up as "Authorization: Basic <user>:<passwd>" where
+                                * "<user>:<passwd>" is base64 encoded.
                                 */
                                tptr = skip_whitespace(iobuf + sizeof("Authorization:")-1);
                                if (STRNCASECMP(tptr, "Basic") != 0)
@@ -1703,30 +2065,96 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
                                tptr += sizeof("Basic")-1;
                                /* decodeBase64() skips whitespace itself */
                                decodeBase64(tptr);
-                               credentials = checkPerm(urlcopy, tptr);
+                               authorized = check_user_passwd(urlcopy, tptr);
+                       }
+#endif
+#if ENABLE_FEATURE_HTTPD_RANGES
+                       if (STRNCASECMP(iobuf, "Range:") == 0) {
+                               /* We know only bytes=NNN-[MMM] */
+                               char *s = skip_whitespace(iobuf + sizeof("Range:")-1);
+                               if (strncmp(s, "bytes=", 6) == 0) {
+                                       s += sizeof("bytes=")-1;
+                                       range_start = BB_STRTOOFF(s, &s, 10);
+                                       if (s[0] != '-' || range_start < 0) {
+                                               range_start = 0;
+                                       } else if (s[1]) {
+                                               range_end = BB_STRTOOFF(s+1, NULL, 10);
+                                               if (errno || range_end < range_start)
+                                                       range_start = 0;
+                                       }
+                               }
+                       }
+#endif
+#if ENABLE_FEATURE_HTTPD_GZIP
+                       if (STRNCASECMP(iobuf, "Accept-Encoding:") == 0) {
+                               /* Note: we do not support "gzip;q=0"
+                                * method of _disabling_ gzip
+                                * delivery. No one uses that, though */
+                               const char *s = strstr(iobuf, "gzip");
+                               if (s) {
+                                       // want more thorough checks?
+                                       //if (s[-1] == ' '
+                                       // || s[-1] == ','
+                                       // || s[-1] == ':'
+                                       //) {
+                                               content_gzip = 1;
+                                       //}
+                               }
                        }
-#endif          /* FEATURE_HTTPD_BASIC_AUTH */
+#endif
                } /* while extra header reading */
        }
 
-       /* We read headers, disable peer timeout */
+       /* We are done reading headers, disable peer timeout */
        alarm(0);
 
-       if (strcmp(bb_basename(urlcopy), httpd_conf) == 0 || ip_allowed == 0) {
-               /* protect listing [/path]/httpd_conf or IP deny */
+       if (strcmp(bb_basename(urlcopy), HTTPD_CONF) == 0 || !ip_allowed) {
+               /* protect listing [/path]/httpd.conf or IP deny */
                send_headers_and_exit(HTTP_FORBIDDEN);
        }
 
 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
-       if (credentials <= 0 && checkPerm(urlcopy, ":") == 0) {
+       /* Case: no "Authorization:" was seen, but page does require passwd.
+        * Check that with dummy user:pass */
+       if (authorized < 0)
+               authorized = check_user_passwd(urlcopy, ":");
+       if (!authorized)
                send_headers_and_exit(HTTP_UNAUTHORIZED);
-       }
 #endif
 
        if (found_moved_temporarily) {
                send_headers_and_exit(HTTP_MOVED_TEMPORARILY);
        }
 
+#if ENABLE_FEATURE_HTTPD_PROXY
+       if (proxy_entry != NULL) {
+               int proxy_fd;
+               len_and_sockaddr *lsa;
+
+               proxy_fd = socket(AF_INET, SOCK_STREAM, 0);
+               if (proxy_fd < 0)
+                       send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
+               lsa = host2sockaddr(proxy_entry->host_port, 80);
+               if (lsa == NULL)
+                       send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
+               if (connect(proxy_fd, &lsa->u.sa, lsa->len) < 0)
+                       send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
+               fdprintf(proxy_fd, "%s %s%s%s%s HTTP/%c.%c\r\n",
+                               prequest, /* GET or POST */
+                               proxy_entry->url_to, /* url part 1 */
+                               urlcopy + strlen(proxy_entry->url_from), /* url part 2 */
+                               (g_query ? "?" : ""), /* "?" (maybe) */
+                               (g_query ? g_query : ""), /* query string (maybe) */
+                               http_major_version, http_minor_version);
+               header_ptr[0] = '\r';
+               header_ptr[1] = '\n';
+               header_ptr += 2;
+               write(proxy_fd, header_buf, header_ptr - header_buf);
+               free(header_buf); /* on the order of 8k, free it */
+               cgi_io_loop_and_exit(proxy_fd, proxy_fd, length);
+       }
+#endif
+
        tptr = urlcopy + 1;      /* skip first '/' */
 
 #if ENABLE_FEATURE_HTTPD_CGI
@@ -1737,8 +2165,12 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
                }
                send_cgi_and_exit(urlcopy, prequest, length, cookie, content_type);
        }
+#endif
+
+       if (urlp[-1] == '/')
+               strcpy(urlp, index_page);
+       if (stat(tptr, &sb) == 0) {
 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
-       {
                char *suffix = strrchr(tptr, '.');
                if (suffix) {
                        Htaccess *cur;
@@ -1748,18 +2180,8 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
                                }
                        }
                }
-       }
 #endif
-       if (prequest != request_GET) {
-               send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
-       }
-#endif  /* FEATURE_HTTPD_CGI */
-
-       if (urlp[-1] == '/')
-               strcpy(urlp, "index.html");
-       if (stat(tptr, &sb) == 0) {
-               /* It's a dir URL and there is index.html */
-               ContentLength = sb.st_size;
+               file_size = sb.st_size;
                last_mod = sb.st_mtime;
        }
 #if ENABLE_FEATURE_HTTPD_CGI
@@ -1772,13 +2194,18 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
                        send_cgi_and_exit("/cgi-bin/index.cgi", prequest, length, cookie, content_type);
                }
        }
-#endif
-       /* else {
-        *      fall through to send_file, it errors out if open fails
-        * }
-        */
+       /* else fall through to send_file, it errors out if open fails: */
 
-       send_file_and_exit(tptr);
+       if (prequest != request_GET && prequest != request_HEAD) {
+               /* POST for files does not make sense */
+               send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
+       }
+       send_file_and_exit(tptr,
+               (prequest != request_HEAD ? SEND_HEADERS_AND_BODY : SEND_HEADERS)
+       );
+#else
+       send_file_and_exit(tptr, SEND_HEADERS_AND_BODY);
+#endif
 }
 
 /*
@@ -1788,7 +2215,7 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
  * Never returns.
  */
 #if BB_MMU
-static void mini_httpd(int server_socket) ATTRIBUTE_NORETURN;
+static void mini_httpd(int server_socket) NORETURN;
 static void mini_httpd(int server_socket)
 {
        /* NB: it's best to not use xfuncs in this loop before fork().
@@ -1799,22 +2226,20 @@ static void mini_httpd(int server_socket)
        while (1) {
                int n;
                len_and_sockaddr fromAddr;
-               
+
                /* Wait for connections... */
                fromAddr.len = LSA_SIZEOF_SA;
-               n = accept(server_socket, &fromAddr.sa, &fromAddr.len);
-
+               n = accept(server_socket, &fromAddr.u.sa, &fromAddr.len);
                if (n < 0)
                        continue;
+
                /* set the KEEPALIVE option to cull dead connections */
                setsockopt(n, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
 
                if (fork() == 0) {
                        /* child */
-#if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
                        /* Do not reload config on HUP */
                        signal(SIGHUP, SIG_IGN);
-#endif
                        close(server_socket);
                        xmove_fd(n, 0);
                        xdup2(0, 1);
@@ -1827,7 +2252,7 @@ static void mini_httpd(int server_socket)
        /* never reached */
 }
 #else
-static void mini_httpd_nommu(int server_socket, int argc, char **argv) ATTRIBUTE_NORETURN;
+static void mini_httpd_nommu(int server_socket, int argc, char **argv) NORETURN;
 static void mini_httpd_nommu(int server_socket, int argc, char **argv)
 {
        char *argv_copy[argc + 2];
@@ -1844,22 +2269,20 @@ static void mini_httpd_nommu(int server_socket, int argc, char **argv)
        while (1) {
                int n;
                len_and_sockaddr fromAddr;
-               
+
                /* Wait for connections... */
                fromAddr.len = LSA_SIZEOF_SA;
-               n = accept(server_socket, &fromAddr.sa, &fromAddr.len);
-
+               n = accept(server_socket, &fromAddr.u.sa, &fromAddr.len);
                if (n < 0)
                        continue;
+
                /* set the KEEPALIVE option to cull dead connections */
                setsockopt(n, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
 
                if (vfork() == 0) {
                        /* child */
-#if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
                        /* Do not reload config on HUP */
                        signal(SIGHUP, SIG_IGN);
-#endif
                        close(server_socket);
                        xmove_fd(n, 0);
                        xdup2(0, 1);
@@ -1878,39 +2301,31 @@ static void mini_httpd_nommu(int server_socket, int argc, char **argv)
  * Process a HTTP connection on stdin/out.
  * Never returns.
  */
-static void mini_httpd_inetd(void) ATTRIBUTE_NORETURN;
+static void mini_httpd_inetd(void) NORETURN;
 static void mini_httpd_inetd(void)
 {
        len_and_sockaddr fromAddr;
 
+       memset(&fromAddr, 0, sizeof(fromAddr));
        fromAddr.len = LSA_SIZEOF_SA;
-       getpeername(0, &fromAddr.sa, &fromAddr.len);
+       /* NB: can fail if user runs it by hand and types in http cmds */
+       getpeername(0, &fromAddr.u.sa, &fromAddr.len);
        handle_incoming_and_exit(&fromAddr);
 }
 
-#if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
-static void sighup_handler(int sig)
+static void sighup_handler(int sig UNUSED_PARAM)
 {
-       struct sigaction sa;
-
-       parse_conf(default_path_httpd_conf, sig == SIGHUP ? SIGNALED_PARSE : FIRST_PARSE);
-
-       memset(&sa, 0, sizeof(sa));
-       sa.sa_handler = sighup_handler;
-       /*sigemptyset(&sa.sa_mask); - memset should be enough */
-       sa.sa_flags = SA_RESTART;
-       sigaction(SIGHUP, &sa, NULL);
+       parse_conf(DEFAULT_PATH_HTTPD_CONF, SIGNALED_PARSE);
 }
-#endif
 
 enum {
        c_opt_config_file = 0,
        d_opt_decode_url,
        h_opt_home_httpd,
-       USE_FEATURE_HTTPD_ENCODE_URL_STR(e_opt_encode_url,)
-       USE_FEATURE_HTTPD_BASIC_AUTH(    r_opt_realm     ,)
-       USE_FEATURE_HTTPD_AUTH_MD5(      m_opt_md5       ,)
-       USE_FEATURE_HTTPD_SETUID(        u_opt_setuid    ,)
+       IF_FEATURE_HTTPD_ENCODE_URL_STR(e_opt_encode_url,)
+       IF_FEATURE_HTTPD_BASIC_AUTH(    r_opt_realm     ,)
+       IF_FEATURE_HTTPD_AUTH_MD5(      m_opt_md5       ,)
+       IF_FEATURE_HTTPD_SETUID(        u_opt_setuid    ,)
        p_opt_port      ,
        p_opt_inetd     ,
        p_opt_foreground,
@@ -1918,10 +2333,10 @@ enum {
        OPT_CONFIG_FILE = 1 << c_opt_config_file,
        OPT_DECODE_URL  = 1 << d_opt_decode_url,
        OPT_HOME_HTTPD  = 1 << h_opt_home_httpd,
-       OPT_ENCODE_URL  = USE_FEATURE_HTTPD_ENCODE_URL_STR((1 << e_opt_encode_url)) + 0,
-       OPT_REALM       = USE_FEATURE_HTTPD_BASIC_AUTH(    (1 << r_opt_realm     )) + 0,
-       OPT_MD5         = USE_FEATURE_HTTPD_AUTH_MD5(      (1 << m_opt_md5       )) + 0,
-       OPT_SETUID      = USE_FEATURE_HTTPD_SETUID(        (1 << u_opt_setuid    )) + 0,
+       OPT_ENCODE_URL  = IF_FEATURE_HTTPD_ENCODE_URL_STR((1 << e_opt_encode_url)) + 0,
+       OPT_REALM       = IF_FEATURE_HTTPD_BASIC_AUTH(    (1 << r_opt_realm     )) + 0,
+       OPT_MD5         = IF_FEATURE_HTTPD_AUTH_MD5(      (1 << m_opt_md5       )) + 0,
+       OPT_SETUID      = IF_FEATURE_HTTPD_SETUID(        (1 << u_opt_setuid    )) + 0,
        OPT_PORT        = 1 << p_opt_port,
        OPT_INETD       = 1 << p_opt_inetd,
        OPT_FOREGROUND  = 1 << p_opt_foreground,
@@ -1929,16 +2344,16 @@ enum {
 };
 
 
-int httpd_main(int argc, char **argv);
-int httpd_main(int argc, char **argv)
+int httpd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int httpd_main(int argc UNUSED_PARAM, char **argv)
 {
        int server_socket = server_socket; /* for gcc */
        unsigned opt;
        char *url_for_decode;
-       USE_FEATURE_HTTPD_ENCODE_URL_STR(const char *url_for_encode;)
-       USE_FEATURE_HTTPD_SETUID(const char *s_ugid = NULL;)
-       USE_FEATURE_HTTPD_SETUID(struct bb_uidgid_t ugid;)
-       USE_FEATURE_HTTPD_AUTH_MD5(const char *pass;)
+       IF_FEATURE_HTTPD_ENCODE_URL_STR(const char *url_for_encode;)
+       IF_FEATURE_HTTPD_SETUID(const char *s_ugid = NULL;)
+       IF_FEATURE_HTTPD_SETUID(struct bb_uidgid_t ugid;)
+       IF_FEATURE_HTTPD_AUTH_MD5(const char *pass;)
 
        INIT_G();
 
@@ -1951,19 +2366,19 @@ int httpd_main(int argc, char **argv)
        /* -v counts, -i implies -f */
        opt_complementary = "vv:if";
        /* We do not "absolutize" path given by -h (home) opt.
-        * If user gives relative path in -h, $SCRIPT_FILENAME can end up
-        * relative too. */
+        * If user gives relative path in -h,
+        * $SCRIPT_FILENAME will not be set. */
        opt = getopt32(argv, "c:d:h:"
-                       USE_FEATURE_HTTPD_ENCODE_URL_STR("e:")
-                       USE_FEATURE_HTTPD_BASIC_AUTH("r:")
-                       USE_FEATURE_HTTPD_AUTH_MD5("m:")
-                       USE_FEATURE_HTTPD_SETUID("u:")
+                       IF_FEATURE_HTTPD_ENCODE_URL_STR("e:")
+                       IF_FEATURE_HTTPD_BASIC_AUTH("r:")
+                       IF_FEATURE_HTTPD_AUTH_MD5("m:")
+                       IF_FEATURE_HTTPD_SETUID("u:")
                        "p:ifv",
-                       &configFile, &url_for_decode, &home_httpd
-                       USE_FEATURE_HTTPD_ENCODE_URL_STR(, &url_for_encode)
-                       USE_FEATURE_HTTPD_BASIC_AUTH(, &g_realm)
-                       USE_FEATURE_HTTPD_AUTH_MD5(, &pass)
-                       USE_FEATURE_HTTPD_SETUID(, &s_ugid)
+                       &opt_c_configFile, &url_for_decode, &home_httpd
+                       IF_FEATURE_HTTPD_ENCODE_URL_STR(, &url_for_encode)
+                       IF_FEATURE_HTTPD_BASIC_AUTH(, &g_realm)
+                       IF_FEATURE_HTTPD_AUTH_MD5(, &pass)
+                       IF_FEATURE_HTTPD_SETUID(, &s_ugid)
                        , &bind_addr_or_port
                        , &verbose
                );
@@ -1979,15 +2394,18 @@ int httpd_main(int argc, char **argv)
 #endif
 #if ENABLE_FEATURE_HTTPD_AUTH_MD5
        if (opt & OPT_MD5) {
-               puts(pw_encrypt(pass, "$1$"));
+               char salt[sizeof("$1$XXXXXXXX")];
+               salt[0] = '$';
+               salt[1] = '1';
+               salt[2] = '$';
+               crypt_make_salt(salt + 3, 4, 0);
+               puts(pw_encrypt(pass, salt, 1));
                return 0;
        }
 #endif
 #if ENABLE_FEATURE_HTTPD_SETUID
        if (opt & OPT_SETUID) {
-               if (!get_uidgid(&ugid, s_ugid, 1))
-                       bb_error_msg_and_die("unrecognized user[:group] "
-                                               "name '%s'", s_ugid);
+               xget_uidgid(&ugid, s_ugid);
        }
 #endif
 
@@ -2014,10 +2432,16 @@ int httpd_main(int argc, char **argv)
 #endif
        }
 
-#if ENABLE_FEATURE_HTTPD_CGI
+#if 0
+       /* User can do it himself: 'env - PATH="$PATH" httpd'
+        * We don't do it because we don't want to screw users
+        * which want to do
+        * 'env - VAR1=val1 VAR2=val2 httpd'
+        * and have VAR1 and VAR2 values visible in their CGIs.
+        * Besides, it is also smaller. */
        {
                char *p = getenv("PATH");
-               /* env strings themself are not freed, no need to strdup(p): */
+               /* env strings themself are not freed, no need to xstrdup(p): */
                clearenv();
                if (p)
                        putenv(p - 5);
@@ -2026,12 +2450,9 @@ int httpd_main(int argc, char **argv)
        }
 #endif
 
-#if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
+       parse_conf(DEFAULT_PATH_HTTPD_CONF, FIRST_PARSE);
        if (!(opt & OPT_INETD))
-               sighup_handler(0);
-       else /* do not install HUP handler in inetd mode */
-#endif
-               parse_conf(default_path_httpd_conf, FIRST_PARSE);
+               signal(SIGHUP, sighup_handler);
 
        xfunc_error_retval = 0;
        if (opt & OPT_INETD)