diff options
Diffstat (limited to 'web/apache/request.cxx')
| -rw-r--r-- | web/apache/request.cxx | 592 |
1 files changed, 484 insertions, 108 deletions
diff --git a/web/apache/request.cxx b/web/apache/request.cxx index 32a1737..a019183 100644 --- a/web/apache/request.cxx +++ b/web/apache/request.cxx @@ -4,13 +4,20 @@ #include <web/apache/request.hxx> -#include <apr_tables.h> // apr_table_*, apr_array_header_t +#include <apr.h> // APR_SIZE_MAX +#include <apr_errno.h> // apr_status_t, APR_SUCCESS, APR_E*, apr_strerror() +#include <apr_tables.h> // apr_table_*, apr_table_*(), apr_array_header_t #include <apr_strings.h> // apr_pstrdup() +#include <apr_buckets.h> // apr_bucket*, apr_bucket_*(), apr_brigade_*(), + // APR_BRIGADE_*() #include <httpd.h> // request_rec, HTTP_*, OK #include <http_protocol.h> // ap_*() -#include <strings.h> // strcasecmp(), strncasecmp() +#include <apreq2/apreq.h> // APREQ_* +#include <apreq2/apreq_util.h> // apreq_brigade_copy() +#include <apreq2/apreq_param.h> // apreq_param_t, apreq_value_to_param() +#include <apreq2/apreq_parser.h> // apreq_parser_t, apreq_parser_make() #include <ctime> // strftime(), time_t #include <vector> @@ -22,11 +29,13 @@ #include <istream> #include <cstring> // str*(), memcpy(), size_t #include <utility> // move() -#include <stdexcept> // invalid_argument +#include <iterator> // istreambuf_iterator +#include <stdexcept> // invalid_argument, runtime_error #include <exception> // current_exception() #include <streambuf> #include <algorithm> // min() +#include <libbutl/utility.mxx> // casecmp() #include <libbutl/optional.mxx> #include <libbutl/timestamp.mxx> @@ -39,6 +48,13 @@ namespace web { namespace apache { + [[noreturn]] static void + throw_internal_error (apr_status_t s, const string& what) + { + char buf[1024]; + throw runtime_error (what + ": " + apr_strerror (s, buf, sizeof (buf))); + } + // Extend the Apache stream with checking for the read limit and caching // the content if requested. Replay the cached content after rewind. // @@ -160,7 +176,7 @@ namespace web // mode_ = mode::cache; - // Bailout if the end of stream is reached. + // Bail out if the end of stream is reached. // if (eof_) return traits_type::eof (); @@ -230,6 +246,152 @@ namespace web return r; } + // Stream interface for reading from the Apache's bucket brigade. Put back + // is not supported. + // + // Note that reading from a brigade bucket modifies the brigade in the + // general case. For example, reading from a file bucket adds a new heap + // bucket before the file bucket on every read. Traversing/reading through + // such a bucket brigade effectively loads the whole file into the memory, + // so the subsequent brigade traversal results in iterating over the + // loaded heap buckets. + // + // To avoid such a behavior we will make a shallow copy of the original + // bucket brigade, initially and for each rewind. Then, instead of + // iterating, we will always read from the first bucket removing it after + // the use. + // + class istreambuf_buckets: public streambuf + { + public: + // The bucket brigade must exist during the object's lifetime. + // + explicit + istreambuf_buckets (const apr_bucket_brigade* bs) + : orig_buckets_ (bs), + buckets_ (apr_brigade_create (bs->p, bs->bucket_alloc)) + + { + if (buckets_ == nullptr) + throw_internal_error (APR_ENOMEM, "apr_brigade_create"); + + rewind (); // Copy the original buckets. + } + + void + rewind () + { + // Note that apreq_brigade_copy() appends buckets to the destination, + // so we clean it up first. + // + apr_status_t r (apr_brigade_cleanup (buckets_.get ())); + if (r != APR_SUCCESS) + throw_internal_error (r, "apr_brigade_cleanup"); + + r = apreq_brigade_copy ( + buckets_.get (), + const_cast<apr_bucket_brigade*> (orig_buckets_)); + + if (r != APR_SUCCESS) + throw_internal_error (r, "apreq_brigade_copy"); + + setg (nullptr, nullptr, nullptr); + } + + private: + virtual int_type + underflow () + { + if (gptr () < egptr ()) + return traits_type::to_int_type (*gptr ()); + + // If the get-pointer is not NULL then it points to the data referred + // by the first brigade bucket. As we will bail out or rewrite such a + // pointer now there is no need for the bucket either, so we can + // safely delete it. + // + if (gptr () != nullptr) + { + assert (!APR_BRIGADE_EMPTY (buckets_)); + + // Note that apr_bucket_delete() is a macro and the following + // call ends up badly (with SIGSEGV). + // + // apr_bucket_delete (APR_BRIGADE_FIRST (buckets_)); + // + apr_bucket* b (APR_BRIGADE_FIRST (buckets_)); + apr_bucket_delete (b); + } + + if (APR_BRIGADE_EMPTY (buckets_)) + return traits_type::eof (); + + apr_size_t n; + const char* d; + apr_bucket* b (APR_BRIGADE_FIRST (buckets_)); + apr_status_t r (apr_bucket_read (b, &d, &n, APR_BLOCK_READ)); + + if (r != APR_SUCCESS) + throw_internal_error (r, "apr_bucket_read"); + + char* p (const_cast<char*> (d)); + setg (p, p, p + n); + return traits_type::to_int_type (*gptr ()); + } + + private: + const apr_bucket_brigade* orig_buckets_; + + struct brigade_deleter + { + void operator() (apr_bucket_brigade* p) const + { + if (p != nullptr) + { + apr_status_t r (apr_brigade_destroy (p)); + + // Shouldn't fail unless something is severely damaged. + // + assert (r == APR_SUCCESS); + } + } + }; + + unique_ptr<apr_bucket_brigade, brigade_deleter> buckets_; + }; + + class istream_buckets_base + { + public: + explicit + istream_buckets_base (const apr_bucket_brigade* bs): buf_ (bs) {} + + protected: + istreambuf_buckets buf_; + }; + + class istream_buckets: public istream_buckets_base, public istream + { + public: + explicit + istream_buckets (const apr_bucket_brigade* bs) + // Note that calling dtor for istream object before init() is called + // is undefined behavior. That's the reason for inventing the + // istream_buckets_base class. + // + : istream_buckets_base (bs), istream (&buf_) + { + exceptions (failbit | badbit); + } + + void + rewind () + { + buf_.rewind (); + clear (); // Clears *bit flags (in particular eofbit). + } + }; + // request // request:: @@ -305,17 +467,27 @@ namespace web ap_set_content_type (rec_, nullptr); // Unset the output content type. - if (in_ != nullptr) - rewind_istream (); - } + // We don't need to rewind the input stream (which well may fail if + // unbuffered) if the form data is already read. + // + if (in_ != nullptr && form_data_ == nullptr) + { + assert (in_buf_ != nullptr); - void request:: - rewind_istream () - { - assert (in_buf_ != nullptr && in_ != nullptr); + in_buf_->rewind (); // Throws if impossible to rewind. + in_->clear (); // Clears *bit flags (in particular eofbit). + } - in_buf_->rewind (); // Throws if impossible to rewind. - in_->clear (); // Clears *bit flags (in particular eofbit). + // Rewind uploaded file streams. + // + if (uploads_ != nullptr) + { + for (const unique_ptr<istream_buckets>& is: *uploads_) + { + if (is != nullptr) + is->rewind (); + } + } } istream& request:: @@ -332,11 +504,6 @@ namespace web in_.reset (new istream (in_buf.get ())); in_buf_ = move (in_buf); in_->exceptions (istream::failbit | istream::badbit); - - // Save form data now otherwise will not be available to do later when - // data is already read from stream. - // - form_data (); } else { @@ -363,26 +530,309 @@ namespace web } const name_values& request:: - parameters () + parameters (size_t limit, bool url_only) { - if (parameters_ == nullptr) + if (parameters_ == nullptr || url_only < url_only_parameters_) { - parameters_.reset (new name_values ()); - try { - parse_parameters (rec_->args); - parse_parameters (form_data ().c_str ()); + if (parameters_ == nullptr) + { + parameters_.reset (new name_values ()); + parse_url_parameters (rec_->args); + } + + if (!url_only && form_data (limit)) + { + // After the form data is parsed we can clean it up for the + // application/x-www-form-urlencoded encoding but not for the + // multipart/form-data (see parse_multipart_parameters() for + // details). + // + if (form_multipart_) + parse_multipart_parameters (*form_data_); + else + { + // Make the character vector a NULL-terminated string. + // + form_data_->push_back ('\0'); + + parse_url_parameters (form_data_->data ()); + *form_data_ = vector<char> (); // Reset the cache. + } + } } - catch (const invalid_argument& ) + catch (const invalid_argument&) { throw invalid_request (); } + + url_only_parameters_ = url_only; } return *parameters_; } + bool request:: + form_data (size_t limit) + { + if (form_data_ == nullptr) + { + form_data_.reset (new vector<char> ()); + + // We will not consider POST body as a form data if the request is in + // the reading or later state. + // + if (rec_->method_number == M_POST && state_ < request_state::reading) + { + const char* ct (apr_table_get (rec_->headers_in, "Content-Type")); + + if (ct != nullptr) + { + form_multipart_ = casecmp ("multipart/form-data", ct, 19) == 0; + + if (form_multipart_ || + casecmp ("application/x-www-form-urlencoded", ct, 33) == 0) + *form_data_ = vector<char> ( + istreambuf_iterator<char> (content (limit)), + istreambuf_iterator<char> ()); + } + } + } + + return !form_data_->empty (); + } + + void request:: + parse_url_parameters (const char* args) + { + assert (parameters_ != nullptr); + + for (auto n (args); n != nullptr; ) + { + const char* v (strchr (n, '=')); + const char* e (strchr (n, '&')); + + if (e != nullptr && e < v) + v = nullptr; + + string name (v != nullptr + ? mime_url_decode (n, v) : + (e + ? mime_url_decode (n, e) + : mime_url_decode (n, n + strlen (n)))); + + optional<string> value; + + if (v++) + value = e + ? mime_url_decode (v, e) + : mime_url_decode (v, v + strlen (v)); + + if (!name.empty () || value) + parameters_->emplace_back (move (name), move (value)); + + n = e ? e + 1 : nullptr; + } + } + + void request:: + parse_multipart_parameters (const vector<char>& body) + { + assert (parameters_ != nullptr && uploads_ == nullptr); + + auto throw_bad_request = [] (apr_status_t s, + status_code sc = HTTP_BAD_REQUEST) + { + char buf[1024]; + throw invalid_request (sc, apr_strerror (s, buf, sizeof (buf))); + }; + + // Create the file upload stream list, filling it with NULLs for the + // parameters parsed from the URL query part. + // + uploads_.reset ( + new vector<unique_ptr<istream_buckets>> (parameters_->size ())); + + // All the required objects (parser, input/output buckets, etc.) will be + // allocated in the request memory pool and so will have the HTTP + // request duration lifetime. + // + apr_pool_t* pool (rec_->pool); + + // Create the input bucket brigade containing a single bucket that + // references the form data. + // + apr_bucket_alloc_t* ba (apr_bucket_alloc_create (pool)); + if (ba == nullptr) + throw_internal_error (APR_ENOMEM, "apr_bucket_alloc_create"); + + apr_bucket_brigade* bb (apr_brigade_create (pool, ba)); + if (bb == nullptr) + throw_internal_error (APR_ENOMEM, "apr_brigade_create"); + + apr_bucket* b ( + apr_bucket_immortal_create (body.data (), body.size (), ba)); + + if (b == nullptr) + throw_internal_error (APR_ENOMEM, "apr_bucket_immortal_create"); + + APR_BRIGADE_INSERT_TAIL (bb, b); + + if ((b = apr_bucket_eos_create (ba)) == nullptr) + throw_internal_error (APR_ENOMEM, "apr_bucket_eos_create"); + + APR_BRIGADE_INSERT_TAIL (bb, b); + + // Make sure that the parser will not swap the parsed data to disk + // passing the maximum possible value for the brigade limit. This way + // the resulting buckets will reference the form data directly, making + // no copies. This why we should not reset the form data cache after + // the parsing. + // + // Note that in future we may possibly setup the parser to read from the + // Apache internals directly and enable swapping the data to disk to + // minimize memory consumption. + // + apreq_parser_t* parser ( + apreq_parser_make (pool, + ba, + apr_table_get (rec_->headers_in, "Content-Type"), + apreq_parse_multipart, + APR_SIZE_MAX /* brigade_limit */, + nullptr /* temp_dir */, + nullptr /* hook */, + nullptr /* ctx */)); + + if (parser == nullptr) + throw_internal_error (APR_ENOMEM, "apreq_parser_make"); + + // Create the output table that will be filled with the parsed + // parameters. + // + apr_table_t* params (apr_table_make (pool, APREQ_DEFAULT_NELTS)); + if (params == nullptr) + throw_internal_error (APR_ENOMEM, "apr_table_make"); + + // Parse the form data. + // + apr_status_t r (apreq_parser_run (parser, params, bb)); + if (r != APR_SUCCESS) + throw_bad_request (r); + + // Fill the parameter and file upload stream lists. + // + const apr_array_header_t* ps (apr_table_elts (params)); + size_t n (ps->nelts); + + for (auto p (reinterpret_cast<const apr_table_entry_t*> (ps->elts)); + n--; ++p) + { + assert (p->key != nullptr && p->val != nullptr); + + if (*p->key != '\0') + { + parameters_->emplace_back (p->key, optional<string> (p->val)); + + const apreq_param_t* ap (apreq_value_to_param (p->val)); + assert (ap != nullptr); // Must always be resolvable. + + uploads_->emplace_back (ap->upload != nullptr + ? new istream_buckets (ap->upload) + : nullptr); + } + } + } + + request::uploads_type& request:: + uploads () const + { + if (parameters_ == nullptr || url_only_parameters_) + sequence_error ("web::apache::request::uploads"); + + if (uploads_ == nullptr) + throw invalid_argument ("no uploads"); + + assert (uploads_->size () == parameters_->size ()); + return *uploads_; + } + + istream& request:: + open_upload (size_t index) + { + uploads_type& us (uploads ()); + size_t n (us.size ()); + + if (index >= n) + throw invalid_argument ("invalid index"); + + const unique_ptr<istream_buckets>& is (us[index]); + + if (is == nullptr) + throw invalid_argument ("no upload"); + + return *is; + } + + istream& request:: + open_upload (const string& name) + { + uploads_type& us (uploads ()); + size_t n (us.size ()); + + istream* r (nullptr); + for (size_t i (0); i < n; ++i) + { + if ((*parameters_)[i].name == name) + { + istream* is (us[i].get ()); + + if (is != nullptr) + { + if (r != nullptr) + throw invalid_argument ("multiple uploads for '" + name + "'"); + + r = is; + } + } + } + + if (r == nullptr) + throw invalid_argument ("no upload"); + + return *r; + } + + const name_values& request:: + headers () + { + if (headers_ == nullptr) + { + headers_.reset (new name_values ()); + + const apr_array_header_t* ha (apr_table_elts (rec_->headers_in)); + size_t n (ha->nelts); + + headers_->reserve (n + 1); // One for the custom :Client-IP header. + + auto add = [this] (const char* n, const char* v) + { + assert (n != nullptr && v != nullptr); + headers_->emplace_back (n, optional<string> (v)); + }; + + for (auto h (reinterpret_cast<const apr_table_entry_t*> (ha->elts)); + n--; ++h) + add (h->key, h->val); + + assert (rec_->connection != nullptr); + + add (":Client-IP", rec_->connection->client_ip); + } + + return *headers_; + } + const name_values& request:: cookies () { @@ -393,10 +843,12 @@ namespace web const apr_array_header_t* ha (apr_table_elts (rec_->headers_in)); size_t n (ha->nelts); - for (auto h (reinterpret_cast<const apr_table_entry_t *> (ha->elts)); + for (auto h (reinterpret_cast<const apr_table_entry_t*> (ha->elts)); n--; ++h) { - if (strcasecmp (h->key, "Cookie") == 0) + assert (h->key != nullptr); + + if (casecmp (h->key, "Cookie") == 0) { for (const char* n (h->val); n != nullptr; ) { @@ -447,8 +899,7 @@ namespace web // Same content type. // - strcasecmp (rec_->content_type ? rec_->content_type : "", - type.c_str ()) == 0) + casecmp (type, rec_->content_type ? rec_->content_type : "") == 0) { // No change, return the existing stream. // @@ -463,7 +914,10 @@ namespace web // written. Save form data now to make it available for future // parameters() call. // - form_data (); + // In the rare cases when the form data is expectedly bigger than 64K + // the client can always call parameters(limit) explicitly. + // + form_data (64 * 1024); unique_ptr<streambuf> out_buf ( buffer @@ -548,83 +1002,5 @@ namespace web state (request_state::headers); apr_table_add (rec_->err_headers_out, "Set-Cookie", s.c_str ()); } - - void request:: - parse_parameters (const char* args) - { - for (auto n (args); n != nullptr; ) - { - const char* v (strchr (n, '=')); - const char* e (strchr (n, '&')); - - if (e != nullptr && e < v) - v = nullptr; - - string name (v != nullptr - ? mime_url_decode (n, v) : - (e - ? mime_url_decode (n, e) - : mime_url_decode (n, n + strlen (n)))); - - optional<string> value; - - if (v++) - value = e - ? mime_url_decode (v, e) - : mime_url_decode (v, v + strlen (v)); - - if (!name.empty () || value) - parameters_->emplace_back (move (name), move (value)); - - n = e ? e + 1 : nullptr; - } - } - - const string& request:: - form_data () - { - if (!form_data_) - { - form_data_.reset (new string ()); - - if (rec_->method_number == M_POST) - { - const char* ct (apr_table_get (rec_->headers_in, "Content-Type")); - - if (ct != nullptr && - strncasecmp ("application/x-www-form-urlencoded", ct, 33) == 0) - { - size_t limit (0); - bool rewind (true); - - // Assign some reasonable (64K) input content read/cache limits if - // not done explicitly yet (with the request::content() call). - // Rewind afterwards unless the cache limit is set to zero. - // - if (in_buf_ == nullptr) - limit = 64 * 1024; - else - rewind = in_buf_->cache_limit () > 0; - - istream& istr (content (limit, limit)); - - // Do not throw when eofbit is set (end of stream reached), and - // when failbit is set (getline() failed to extract any character). - // - istream::iostate e (istr.exceptions ()); // Save exception mask. - istr.exceptions (istream::badbit); - getline (istr, *form_data_); - istr.exceptions (e); // Restore exception mask. - - // Rewind the stream unless no buffering were requested beforehand. - // - if (rewind) - rewind_istream (); - } - } - } - - return *form_data_; - } } } |