1 files changed, 457 insertions, 0 deletions
diff --git a/ext/unicorn_http/unicorn_http.c b/ext/unicorn_http/unicorn_http.c
new file mode 100644
index 0000000..41936cd
--- /dev/null
+++ b/ext/unicorn_http/unicorn_http.c
@@ -0,0 +1,457 @@
+/**
+ * Copyright (c) 2009 Eric Wong (all bugs are Eric's fault)
+ * Copyright (c) 2005 Zed A. Shaw
+ * You can redistribute it and/or modify it under the same terms as Ruby.
+ */
+#include "ruby.h"
+#include "ext_help.h"
+#include <assert.h>
+#include <string.h>
+#include "unicorn_http.h"
+
+static http_parser *data_get(VALUE self)
+{
+  http_parser *http;
+
+  Data_Get_Struct(self, http_parser, http);
+  if (!http)
+    rb_raise(rb_eArgError, "NULL found for http when shouldn't be.");
+  return http;
+}
+
+#ifndef RSTRING_PTR
+#define RSTRING_PTR(s) (RSTRING(s)->ptr)
+#endif
+#ifndef RSTRING_LEN
+#define RSTRING_LEN(s) (RSTRING(s)->len)
+#endif
+
+static VALUE mUnicorn;
+static VALUE cHttpParser;
+static VALUE eHttpParserError;
+static VALUE sym_http_body;
+
+#define HTTP_PREFIX "HTTP_"
+#define HTTP_PREFIX_LEN (sizeof(HTTP_PREFIX) - 1)
+
+static VALUE global_rack_url_scheme;
+static VALUE global_request_method;
+static VALUE global_request_uri;
+static VALUE global_fragment;
+static VALUE global_query_string;
+static VALUE global_http_version;
+static VALUE global_request_path;
+static VALUE global_path_info;
+static VALUE global_server_name;
+static VALUE global_server_port;
+static VALUE global_server_protocol;
+static VALUE global_server_protocol_value;
+static VALUE global_http_host;
+static VALUE global_http_x_forwarded_proto;
+static VALUE global_port_80;
+static VALUE global_port_443;
+static VALUE global_localhost;
+static VALUE global_http;
+
+/** Defines common length and error messages for input length validation. */
+#define DEF_MAX_LENGTH(N, length) \
+  static const size_t MAX_##N##_LENGTH = length; \
+  static const char * const MAX_##N##_LENGTH_ERR = \
+    "HTTP element " # N  " is longer than the " # length " allowed length."
+
+/**
+ * Validates the max length of given input and throws an HttpParserError
+ * exception if over.
+ */
+#define VALIDATE_MAX_LENGTH(len, N) do { \
+  if (len > MAX_##N##_LENGTH) \
+    rb_raise(eHttpParserError, MAX_##N##_LENGTH_ERR); \
+} while (0)
+
+/** Defines global strings in the init method. */
+#define DEF_GLOBAL(N, val) do { \
+  global_##N = rb_obj_freeze(rb_str_new(val, sizeof(val) - 1)); \
+  rb_global_variable(&global_##N); \
+} while (0)
+
+/* Defines the maximum allowed lengths for various input elements.*/
+DEF_MAX_LENGTH(FIELD_NAME, 256);
+DEF_MAX_LENGTH(FIELD_VALUE, 80 * 1024);
+DEF_MAX_LENGTH(REQUEST_URI, 1024 * 12);
+DEF_MAX_LENGTH(FRAGMENT, 1024); /* Don't know if this length is specified somewhere or not */
+DEF_MAX_LENGTH(REQUEST_PATH, 1024);
+DEF_MAX_LENGTH(QUERY_STRING, (1024 * 10));
+DEF_MAX_LENGTH(HEADER, (1024 * (80 + 32)));
+
+struct common_field {
+        const signed long len;
+        const char *name;
+        VALUE value;
+};
+
+/*
+ * A list of common HTTP headers we expect to receive.
+ * This allows us to avoid repeatedly creating identical string
+ * objects to be used with rb_hash_aset().
+ */
+static struct common_field common_http_fields[] = {
+# define f(N) { (sizeof(N) - 1), N, Qnil }
+        f("ACCEPT"),
+        f("ACCEPT_CHARSET"),
+        f("ACCEPT_ENCODING"),
+        f("ACCEPT_LANGUAGE"),
+        f("ALLOW"),
+        f("AUTHORIZATION"),
+        f("CACHE_CONTROL"),
+        f("CONNECTION"),
+        f("CONTENT_ENCODING"),
+        f("CONTENT_LENGTH"),
+        f("CONTENT_TYPE"),
+        f("COOKIE"),
+        f("DATE"),
+        f("EXPECT"),
+        f("FROM"),
+        f("HOST"),
+        f("IF_MATCH"),
+        f("IF_MODIFIED_SINCE"),
+        f("IF_NONE_MATCH"),
+        f("IF_RANGE"),
+        f("IF_UNMODIFIED_SINCE"),
+        f("KEEP_ALIVE"), /* Firefox sends this */
+        f("MAX_FORWARDS"),
+        f("PRAGMA"),
+        f("PROXY_AUTHORIZATION"),
+        f("RANGE"),
+        f("REFERER"),
+        f("TE"),
+        f("TRAILER"),
+        f("TRANSFER_ENCODING"),
+        f("UPGRADE"),
+        f("USER_AGENT"),
+        f("VIA"),
+        f("X_FORWARDED_FOR"), /* common for proxies */
+        f("X_FORWARDED_PROTO"), /* common for proxies */
+        f("X_REAL_IP"), /* common for proxies */
+        f("WARNING")
+# undef f
+};
+
+/* this function is not performance-critical */
+static void init_common_fields(void)
+{
+  int i;
+  struct common_field *cf = common_http_fields;
+  char tmp[256]; /* MAX_FIELD_NAME_LENGTH */
+  memcpy(tmp, HTTP_PREFIX, HTTP_PREFIX_LEN);
+
+  for(i = 0; i < ARRAY_SIZE(common_http_fields); cf++, i++) {
+    /* Rack doesn't like certain headers prefixed with "HTTP_" */
+    if (!strcmp("CONTENT_LENGTH", cf->name) ||
+        !strcmp("CONTENT_TYPE", cf->name)) {
+      cf->value = rb_str_new(cf->name, cf->len);
+    } else {
+      memcpy(tmp + HTTP_PREFIX_LEN, cf->name, cf->len + 1);
+      cf->value = rb_str_new(tmp, HTTP_PREFIX_LEN + cf->len);
+    }
+    cf->value = rb_obj_freeze(cf->value);
+    rb_global_variable(&cf->value);
+  }
+}
+
+static VALUE find_common_field_value(const char *field, size_t flen)
+{
+  int i;
+  struct common_field *cf = common_http_fields;
+  for(i = 0; i < ARRAY_SIZE(common_http_fields); i++, cf++) {
+    if (cf->len == flen && !memcmp(cf->name, field, flen))
+      return cf->value;
+  }
+  return Qnil;
+}
+
+static void http_field(void *data, const char *field,
+                       size_t flen, const char *value, size_t vlen)
+{
+  VALUE req = (VALUE)data;
+  VALUE f = Qnil;
+
+  VALIDATE_MAX_LENGTH(flen, FIELD_NAME);
+  VALIDATE_MAX_LENGTH(vlen, FIELD_VALUE);
+
+  f = find_common_field_value(field, flen);
+
+  if (f == Qnil) {
+    /*
+     * We got a strange header that we don't have a memoized value for.
+     * Fallback to creating a new string to use as a hash key.
+     *
+     * using rb_str_new(NULL, len) here is faster than rb_str_buf_new(len)
+     * in my testing, because: there's no minimum allocation length (and
+     * no check for it, either), RSTRING_LEN(f) does not need to be
+     * written twice, and and RSTRING_PTR(f) will already be
+     * null-terminated for us.
+     */
+    f = rb_str_new(NULL, HTTP_PREFIX_LEN + flen);
+    memcpy(RSTRING_PTR(f), HTTP_PREFIX, HTTP_PREFIX_LEN);
+    memcpy(RSTRING_PTR(f) + HTTP_PREFIX_LEN, field, flen);
+    assert(*(RSTRING_PTR(f) + RSTRING_LEN(f)) == '\0'); /* paranoia */
+    /* fprintf(stderr, "UNKNOWN HEADER <%s>\n", RSTRING_PTR(f)); */
+  } else if (f == global_http_host && rb_hash_aref(req, f) != Qnil) {
+    return;
+  }
+
+  rb_hash_aset(req, f, rb_str_new(value, vlen));
+}
+
+static void request_method(void *data, const char *at, size_t length)
+{
+  VALUE req = (VALUE)data;
+  VALUE val = Qnil;
+
+  val = rb_str_new(at, length);
+  rb_hash_aset(req, global_request_method, val);
+}
+
+static void scheme(void *data, const char *at, size_t length)
+{
+  rb_hash_aset((VALUE)data, global_rack_url_scheme, rb_str_new(at, length));
+}
+
+static void host(void *data, const char *at, size_t length)
+{
+  rb_hash_aset((VALUE)data, global_http_host, rb_str_new(at, length));
+}
+
+static void request_uri(void *data, const char *at, size_t length)
+{
+  VALUE req = (VALUE)data;
+  VALUE val = Qnil;
+
+  VALIDATE_MAX_LENGTH(length, REQUEST_URI);
+
+  val = rb_str_new(at, length);
+  rb_hash_aset(req, global_request_uri, val);
+
+  /* "OPTIONS * HTTP/1.1\r\n" is a valid request */
+  if (length == 1 && *at == '*') {
+    val = rb_str_new(NULL, 0);
+    rb_hash_aset(req, global_request_path, val);
+    rb_hash_aset(req, global_path_info, val);
+  }
+}
+
+static void fragment(void *data, const char *at, size_t length)
+{
+  VALUE req = (VALUE)data;
+  VALUE val = Qnil;
+
+  VALIDATE_MAX_LENGTH(length, FRAGMENT);
+
+  val = rb_str_new(at, length);
+  rb_hash_aset(req, global_fragment, val);
+}
+
+static void request_path(void *data, const char *at, size_t length)
+{
+  VALUE req = (VALUE)data;
+  VALUE val = Qnil;
+
+  VALIDATE_MAX_LENGTH(length, REQUEST_PATH);
+
+  val = rb_str_new(at, length);
+  rb_hash_aset(req, global_request_path, val);
+
+  /* rack says PATH_INFO must start with "/" or be empty */
+  if (!(length == 1 && *at == '*'))
+    rb_hash_aset(req, global_path_info, val);
+}
+
+static void query_string(void *data, const char *at, size_t length)
+{
+  VALUE req = (VALUE)data;
+  VALUE val = Qnil;
+
+  VALIDATE_MAX_LENGTH(length, QUERY_STRING);
+
+  val = rb_str_new(at, length);
+  rb_hash_aset(req, global_query_string, val);
+}
+
+static void http_version(void *data, const char *at, size_t length)
+{
+  VALUE req = (VALUE)data;
+  VALUE val = rb_str_new(at, length);
+  rb_hash_aset(req, global_http_version, val);
+}
+
+/** Finalizes the request header to have a bunch of stuff that's needed. */
+static void header_done(void *data, const char *at, size_t length)
+{
+  VALUE req = (VALUE)data;
+  VALUE server_name = global_localhost;
+  VALUE server_port = global_port_80;
+  VALUE temp;
+
+  /* rack requires QUERY_STRING */
+  if (rb_hash_aref(req, global_query_string) == Qnil)
+    rb_hash_aset(req, global_query_string, rb_str_new(NULL, 0));
+
+  /* set rack.url_scheme to "https" or "http", no others are allowed by Rack */
+  if ((temp = rb_hash_aref(req, global_rack_url_scheme)) == Qnil) {
+    if ((temp = rb_hash_aref(req, global_http_x_forwarded_proto)) != Qnil &&
+        RSTRING_LEN(temp) == 5 &&
+        !memcmp("https", RSTRING_PTR(temp), 5))
+      server_port = global_port_443;
+    else
+      temp = global_http;
+    rb_hash_aset(req, global_rack_url_scheme, temp);
+  } else if (RSTRING_LEN(temp) == 5 && !memcmp("https", RSTRING_PTR(temp), 5)) {
+    server_port = global_port_443;
+  }
+
+  /* parse and set the SERVER_NAME and SERVER_PORT variables */
+  if ((temp = rb_hash_aref(req, global_http_host)) != Qnil) {
+    char *colon = memchr(RSTRING_PTR(temp), ':', RSTRING_LEN(temp));
+    if (colon) {
+      long port_start = colon - RSTRING_PTR(temp) + 1;
+
+      server_name = rb_str_substr(temp, 0, colon - RSTRING_PTR(temp));
+      if ((RSTRING_LEN(temp) - port_start) > 0)
+        server_port = rb_str_substr(temp, port_start, RSTRING_LEN(temp));
+    } else {
+      server_name = temp;
+    }
+  }
+  rb_hash_aset(req, global_server_name, server_name);
+  rb_hash_aset(req, global_server_port, server_port);
+  rb_hash_aset(req, global_server_protocol, global_server_protocol_value);
+
+  /* grab the initial body and stuff it into the hash */
+  temp = rb_hash_aref(req, global_request_method);
+  if (temp != Qnil) {
+    long len = RSTRING_LEN(temp);
+    char *ptr = RSTRING_PTR(temp);
+
+    if (memcmp(ptr, "HEAD", len) && memcmp(ptr, "GET", len))
+      rb_hash_aset(req, sym_http_body, rb_str_new(at, length));
+  }
+}
+
+static void HttpParser_free(void *data) {
+  TRACE();
+
+  if(data) {
+    free(data);
+  }
+}
+
+
+static VALUE HttpParser_alloc(VALUE klass)
+{
+  VALUE obj;
+  http_parser *hp = ALLOC_N(http_parser, 1);
+  TRACE();
+  http_parser_init(hp);
+
+  obj = Data_Wrap_Struct(klass, NULL, HttpParser_free, hp);
+
+  return obj;
+}
+
+
+/**
+ * call-seq:
+ *    parser.new -> parser
+ *
+ * Creates a new parser.
+ */
+static VALUE HttpParser_init(VALUE self)
+{
+  http_parser_init(data_get(self));
+
+  return self;
+}
+
+
+/**
+ * call-seq:
+ *    parser.reset -> nil
+ *
+ * Resets the parser to it's initial state so that you can reuse it
+ * rather than making new ones.
+ */
+static VALUE HttpParser_reset(VALUE self)
+{
+  http_parser_init(data_get(self));
+
+  return Qnil;
+}
+
+
+/**
+ * call-seq:
+ *    parser.execute(req_hash, data) -> true/false
+ *
+ * Takes a Hash and a String of data, parses the String of data filling
+ * in the Hash returning a boolean to indicate whether or not parsing
+ * is finished.
+ * 
+ * This function now throws an exception when there is a parsing error.
+ * This makes the logic for working with the parser much easier.  You
+ * will need to wrap the parser with an exception handling block.
+ */
+
+static VALUE HttpParser_execute(VALUE self, VALUE req_hash, VALUE data)
+{
+  http_parser *http = data_get(self);
+  char *dptr = RSTRING_PTR(data);
+  long dlen = RSTRING_LEN(data);
+
+  if (http->nread < dlen) {
+    http->data = (void *)req_hash;
+    http_parser_execute(http, dptr, dlen);
+
+    VALIDATE_MAX_LENGTH(http->nread, HEADER);
+
+    if (!http_parser_has_error(http))
+      return http_parser_is_finished(http) ? Qtrue : Qfalse;
+
+    rb_raise(eHttpParserError, "Invalid HTTP format, parsing fails.");
+  }
+  rb_raise(eHttpParserError, "Requested start is after data buffer end.");
+}
+
+void Init_unicorn_http(void)
+{
+  mUnicorn = rb_define_module("Unicorn");
+
+  DEF_GLOBAL(rack_url_scheme, "rack.url_scheme");
+  DEF_GLOBAL(request_method, "REQUEST_METHOD");
+  DEF_GLOBAL(request_uri, "REQUEST_URI");
+  DEF_GLOBAL(fragment, "FRAGMENT");
+  DEF_GLOBAL(query_string, "QUERY_STRING");
+  DEF_GLOBAL(http_version, "HTTP_VERSION");
+  DEF_GLOBAL(request_path, "REQUEST_PATH");
+  DEF_GLOBAL(path_info, "PATH_INFO");
+  DEF_GLOBAL(server_name, "SERVER_NAME");
+  DEF_GLOBAL(server_port, "SERVER_PORT");
+  DEF_GLOBAL(server_protocol, "SERVER_PROTOCOL");
+  DEF_GLOBAL(server_protocol_value, "HTTP/1.1");
+  DEF_GLOBAL(http_x_forwarded_proto, "HTTP_X_FORWARDED_PROTO");
+  DEF_GLOBAL(port_80, "80");
+  DEF_GLOBAL(port_443, "443");
+  DEF_GLOBAL(localhost, "localhost");
+  DEF_GLOBAL(http, "http");
+
+  eHttpParserError = rb_define_class_under(mUnicorn, "HttpParserError", rb_eIOError);
+
+  cHttpParser = rb_define_class_under(mUnicorn, "HttpParser", rb_cObject);
+  rb_define_alloc_func(cHttpParser, HttpParser_alloc);
+  rb_define_method(cHttpParser, "initialize", HttpParser_init,0);
+  rb_define_method(cHttpParser, "reset", HttpParser_reset,0);
+  rb_define_method(cHttpParser, "execute", HttpParser_execute,2);
+  sym_http_body = ID2SYM(rb_intern("http_body"));
+  init_common_fields();
+  global_http_host = find_common_field_value("HOST", 4);
+  assert(global_http_host != Qnil);
+}