httpd: put all headers into environment as HTTP_UPPERCASED_HEADER=val
authorDenys Vlasenko <vda.linux@googlemail.com>
Tue, 16 Apr 2019 09:37:02 +0000 (11:37 +0200)
committerDenys Vlasenko <vda.linux@googlemail.com>
Tue, 16 Apr 2019 09:37:02 +0000 (11:37 +0200)
Set up environment variables before running the CGI script.
The variables will be named HTTP_<filtered_name> where the <filtered_name>
is the header name capitalized and all characters not matching
[a-z] | [A-Z] | [0-9] replaced with '_'.

function                                             old     new   delta
http_response                                         80      88      +8
http_response_type                                    20      22      +2
send_headers                                         718     715      -3
parse_conf                                          1481    1478      -3
get_line                                             128     110     -18
cgi_io_loop_and_exit                                 599     569     -30
send_cgi_and_exit                                    882     738    -144
handle_incoming_and_exit                            2793    2592    -201
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/6 up/down: 10/-399)          Total: -389 bytes
   text    data     bss     dec     hex filename
 982178     485    7296  989959   f1b07 busybox_old
 981675     485    7296  989456   f1910 busybox_unstripped

Signed-off-by: Alexander Vickberg <wickbergster@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
networking/httpd.c

index 53be500d3fe3d062260783aef77b927a3c7528cb..11c26a8917162819343fd430786e013c86514443 100644 (file)
 #define DEBUG 0
 
 #define IOBUF_SIZE 8192
+#define MAX_HTTP_HEADERS_SIZE ((8*1024) - 16)
 #if PIPE_BUF >= IOBUF_SIZE
 # error "PIPE_BUF >= IOBUF_SIZE"
 #endif
@@ -305,6 +306,13 @@ typedef struct Htaccess_Proxy {
        char *url_to;
 } Htaccess_Proxy;
 
+typedef enum CGI_type {
+       CGI_NONE = 0,
+       CGI_NORMAL,
+       CGI_INDEX,
+       CGI_INTERPRETER,
+} CGI_type;
+
 enum {
        HTTP_OK = 200,
        HTTP_PARTIAL_CONTENT = 206,
@@ -316,6 +324,7 @@ enum {
        HTTP_REQUEST_TIMEOUT = 408,
        HTTP_NOT_IMPLEMENTED = 501,   /* used for unrecognized requests */
        HTTP_INTERNAL_SERVER_ERROR = 500,
+       HTTP_ENTITY_TOO_LARGE = 413,
        HTTP_CONTINUE = 100,
 #if 0   /* future use */
        HTTP_SWITCHING_PROTOCOLS = 101,
@@ -347,6 +356,7 @@ static const uint16_t http_response_type[] ALIGN2 = {
        HTTP_BAD_REQUEST,
        HTTP_FORBIDDEN,
        HTTP_INTERNAL_SERVER_ERROR,
+       HTTP_ENTITY_TOO_LARGE,
 #if 0   /* not implemented */
        HTTP_CREATED,
        HTTP_ACCEPTED,
@@ -377,6 +387,7 @@ static const struct {
        { "Bad Request", "Unsupported method" },
        { "Forbidden", ""  },
        { "Internal Server Error", "Internal Server Error" },
+       { "Entity Too Large", "Entity Too Large" },
 #if 0   /* not implemented */
        { "Created" },
        { "Accepted" },
@@ -412,11 +423,6 @@ struct globals {
 
        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
@@ -1439,23 +1445,17 @@ static void setenv1(const char *name, const char *value)
  * const char *url              The requested URL (with leading /).
  * const char *orig_uri         The original URI before rewriting (if any)
  * 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 *orig_uri,
                const char *request,
-               int post_len,
-               const char *cookie,
-               const char *content_type) NORETURN;
+               int post_len) NORETURN;
 static void send_cgi_and_exit(
                const char *url,
                const char *orig_uri,
                const char *request,
-               int post_len,
-               const char *cookie,
-               const char *content_type)
+               int post_len)
 {
        struct fd_pair fromCgi;  /* CGI -> httpd pipe */
        struct fd_pair toCgi;    /* httpd -> CGI pipe */
@@ -1533,26 +1533,14 @@ static void send_cgi_and_exit(
 #endif
                }
        }
-       setenv1("HTTP_USER_AGENT", G.user_agent);
-       if (G.http_accept)
-               setenv1("HTTP_ACCEPT", G.http_accept);
-       if (G.http_accept_language)
-               setenv1("HTTP_ACCEPT_LANGUAGE", G.http_accept_language);
        if (post_len)
                putenv(xasprintf("CONTENT_LENGTH=%u", post_len));
-       if (cookie)
-               setenv1("HTTP_COOKIE", cookie);
-       if (content_type)
-               setenv1("CONTENT_TYPE", content_type);
 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
        if (remoteuser) {
                setenv1("REMOTE_USER", remoteuser);
                putenv((char*)"AUTH_TYPE=Basic");
        }
 #endif
-       if (G.referer)
-               setenv1("HTTP_REFERER", G.referer);
-       setenv1("HTTP_HOST", G.host); /* set to "" if NULL */
        /* setenv1("SERVER_NAME", safe_gethostname()); - don't do this,
         * just run "env SERVER_NAME=xyz httpd ..." instead */
 
@@ -2083,12 +2071,12 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
        char *urlcopy;
        char *urlp;
        char *tptr;
+       unsigned header_len;
 #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;
+       enum CGI_type cgi_type = CGI_NONE;
 #elif ENABLE_FEATURE_HTTPD_PROXY
 #define prequest request_GET
        unsigned long length = 0;
@@ -2201,7 +2189,9 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
 #if ENABLE_FEATURE_HTTPD_PROXY
        proxy_entry = find_proxy_entry(urlcopy);
        if (proxy_entry)
-               header_buf = header_ptr = xmalloc(IOBUF_SIZE);
+               header_buf = header_ptr = xmalloc(MAX_HTTP_HEADERS_SIZE + 2);
+//TODO: why we don't just start pumping data to proxy here,
+//without decoding URL, saving headers and such???
        else
 #endif
        {
@@ -2275,31 +2265,79 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
                *tptr = '/';
        }
 
+       tptr = urlcopy + 1;      /* skip first '/' */
+
+#if ENABLE_FEATURE_HTTPD_CGI
+       if (is_prefixed_with(tptr, "cgi-bin/")) {
+               if (tptr[8] == '\0') {
+                       /* protect listing "cgi-bin/" */
+                       send_headers_and_exit(HTTP_FORBIDDEN);
+               }
+               cgi_type = CGI_NORMAL;
+       }
+#endif
+
+       if (urlp[-1] == '/') {
+               /* When index_page string is appended to <dir>/ URL, it overwrites
+                * the query string. If we fall back to call /cgi-bin/index.cgi,
+                * query string would be lost and not available to the CGI.
+                * Work around it by making a deep copy.
+                */
+               if (ENABLE_FEATURE_HTTPD_CGI)
+                       g_query = xstrdup(g_query); /* ok for NULL too */
+               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;
+                       for (cur = script_i; cur; cur = cur->next) {
+                               if (strcmp(cur->before_colon + 1, suffix) == 0) {
+                                       cgi_type = CGI_INTERPRETER;
+                                       break;
+                               }
+                       }
+               }
+#endif
+               if (!found_moved_temporarily) {
+                       file_size = sb.st_size;
+                       last_mod = sb.st_mtime;
+               }
+       }
+#if ENABLE_FEATURE_HTTPD_CGI
+       else if (urlp[-1] == '/') {
+               /* It's a dir URL and there is no index.html
+                * Try cgi-bin/index.cgi */
+               if (access("/cgi-bin/index.cgi"+1, X_OK) == 0) {
+                       cgi_type = CGI_INDEX;
+               }
+       }
+#endif
+       urlp[0] = '\0';
+
+       header_len = 0;
        if (http_major_version >= '0') {
                /* Request was with "... HTTP/nXXX", and n >= 0 */
 
                /* Read until blank line */
                while (1) {
-                       if (!get_line())
+                       int iobuf_len = get_line();
+                       if (!iobuf_len)
                                break; /* EOF or error or empty line */
+                       header_len += iobuf_len + 2;
+                       if (header_len >= MAX_HTTP_HEADERS_SIZE)
+                               send_headers_and_exit(HTTP_ENTITY_TOO_LARGE);
                        if (DEBUG)
                                bb_error_msg("header: '%s'", iobuf);
-
 #if ENABLE_FEATURE_HTTPD_PROXY
                        if (proxy_entry) {
-                               /* Why 4, not 2?
-                                * We need 2 more bytes for yet another "\r\n" -
-                                * see near fdprintf(proxy_fd...) further below.
-                                */
-                               int maxlen = (IOBUF_SIZE-4) - (int)(header_ptr - header_buf);
-                               if (maxlen > 0) {
-                                       int len = strnlen(iobuf, maxlen);
-                                       memcpy(header_ptr, iobuf, len);
-                                       header_ptr += len;
-                                       header_ptr[0] = '\r';
-                                       header_ptr[1] = '\n';
-                                       header_ptr += 2;
-                               }
+                               /* protected from overflow by header_len check above */
+                               memcpy(header_ptr, iobuf, iobuf_len);
+                               header_ptr += iobuf_len;
+                               header_ptr[0] = '\r';
+                               header_ptr[1] = '\n';
+                               header_ptr += 2;
                        }
 #endif
 
@@ -2321,30 +2359,7 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
                                        if (errno || length > INT_MAX)
                                                send_headers_and_exit(HTTP_BAD_REQUEST);
                                }
-                       }
-#endif
-#if ENABLE_FEATURE_HTTPD_CGI
-                       else if (STRNCASECMP(iobuf, "Cookie:") == 0) {
-                               if (!cookie) /* in case they send millions of these, do not OOM */
-                                       cookie = xstrdup(skip_whitespace(iobuf + sizeof("Cookie:")-1));
-                       } else if (STRNCASECMP(iobuf, "Content-Type:") == 0) {
-                               if (!content_type)
-                                       content_type = xstrdup(skip_whitespace(iobuf + sizeof("Content-Type:")-1));
-                       } else if (STRNCASECMP(iobuf, "Referer:") == 0) {
-                               if (!G.referer)
-                                       G.referer = xstrdup(skip_whitespace(iobuf + sizeof("Referer:")-1));
-                       } else if (STRNCASECMP(iobuf, "User-Agent:") == 0) {
-                               if (!G.user_agent)
-                                       G.user_agent = xstrdup(skip_whitespace(iobuf + sizeof("User-Agent:")-1));
-                       } else if (STRNCASECMP(iobuf, "Host:") == 0) {
-                               if (!G.host)
-                                       G.host = xstrdup(skip_whitespace(iobuf + sizeof("Host:")-1));
-                       } else if (STRNCASECMP(iobuf, "Accept:") == 0) {
-                               if (!G.http_accept)
-                                       G.http_accept = xstrdup(skip_whitespace(iobuf + sizeof("Accept:")-1));
-                       } else if (STRNCASECMP(iobuf, "Accept-Language:") == 0) {
-                               if (!G.http_accept_language)
-                                       G.http_accept_language = xstrdup(skip_whitespace(iobuf + sizeof("Accept-Language:")-1));
+                               continue;
                        }
 #endif
 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
@@ -2360,6 +2375,7 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
                                /* decodeBase64() skips whitespace itself */
                                decodeBase64(tptr);
                                authorized = check_user_passwd(urlcopy, tptr);
+                               continue;
                        }
 #endif
 #if ENABLE_FEATURE_HTTPD_RANGES
@@ -2377,6 +2393,7 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
                                                        range_start = -1;
                                        }
                                }
+                               continue;
                        }
 #endif
 #if ENABLE_FEATURE_HTTPD_GZIP
@@ -2394,6 +2411,35 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
                                                content_gzip = 1;
                                        //}
                                }
+                               continue;
+                       }
+#endif
+#if ENABLE_FEATURE_HTTPD_CGI
+                       if (cgi_type != CGI_NONE) {
+                               bool ct = (STRNCASECMP(iobuf, "Content-Type:") == 0);
+                               char *cp;
+                               char *colon = strchr(iobuf, ':');
+
+                               if (!colon)
+                                       continue;
+                               cp = iobuf;
+                               while (cp < colon) {
+                                       /* a-z => A-Z, not-alnum => _ */
+                                       char c = (*cp & ~0x20); /* toupper for A-Za-z, undef for others */
+                                       if ((unsigned)(c - 'A') <= ('Z' - 'A')) {
+                                               *cp++ = c;
+                                               continue;
+                                       }
+                                       if (!isdigit(*cp))
+                                               *cp = '_';
+                                       cp++;
+                               }
+                               /* "Content-Type:" gets no HTTP_ prefix, all others do */
+                               cp = xasprintf(ct ? "HTTP_%.*s=%s" + 5 : "HTTP_%.*s=%s",
+                                       (int)(colon - iobuf), iobuf,
+                                       skip_whitespace(colon + 1)
+                               );
+                               putenv(cp);
                        }
 #endif
                } /* while extra header reading */
@@ -2452,51 +2498,20 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
        tptr = urlcopy + 1;      /* skip first '/' */
 
 #if ENABLE_FEATURE_HTTPD_CGI
-       if (is_prefixed_with(tptr, "cgi-bin/")) {
-               if (tptr[8] == '\0') {
-                       /* protect listing "cgi-bin/" */
-                       send_headers_and_exit(HTTP_FORBIDDEN);
-               }
-               send_cgi_and_exit(urlcopy, urlcopy, prequest, length, cookie, content_type);
+       if (cgi_type != CGI_NONE) {
+               send_cgi_and_exit(
+                       (cgi_type == CGI_INDEX) ? "/cgi-bin/index.cgi"
+                       /*CGI_NORMAL or CGI_INTERPRETER*/ : urlcopy,
+                       urlcopy, prequest, length
+               );
        }
 #endif
 
        if (urlp[-1] == '/') {
-               /* When index_page string is appended to <dir>/ URL, it overwrites
-                * the query string. If we fall back to call /cgi-bin/index.cgi,
-                * query string would be lost and not available to the CGI.
-                * Work around it by making a deep copy.
-                */
-               if (ENABLE_FEATURE_HTTPD_CGI)
-                       g_query = xstrdup(g_query); /* ok for NULL too */
                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;
-                       for (cur = script_i; cur; cur = cur->next) {
-                               if (strcmp(cur->before_colon + 1, suffix) == 0) {
-                                       send_cgi_and_exit(urlcopy, urlcopy, prequest, length, cookie, content_type);
-                               }
-                       }
-               }
-#endif
-               file_size = sb.st_size;
-               last_mod = sb.st_mtime;
-       }
-#if ENABLE_FEATURE_HTTPD_CGI
-       else if (urlp[-1] == '/') {
-               /* It's a dir URL and there is no index.html
-                * Try cgi-bin/index.cgi */
-               if (access("/cgi-bin/index.cgi"+1, X_OK) == 0) {
-                       urlp[0] = '\0'; /* remove index_page */
-                       send_cgi_and_exit("/cgi-bin/index.cgi", urlcopy, prequest, length, cookie, content_type);
-               }
-       }
-       /* else fall through to send_file, it errors out if open fails: */
 
+#if ENABLE_FEATURE_HTTPD_CGI
        if (prequest != request_GET && prequest != request_HEAD) {
                /* POST for files does not make sense */
                send_headers_and_exit(HTTP_NOT_IMPLEMENTED);