diff --git a/a.out b/a.out deleted file mode 100755 index 21a2ce9..0000000 Binary files a/a.out and /dev/null differ diff --git a/hw1/Makefile b/hw1/Makefile new file mode 100644 index 0000000..0bae18a --- /dev/null +++ b/hw1/Makefile @@ -0,0 +1,13 @@ +CXXFLAGS := -std=c++17 -DMAGICKCORE_HDRI_ENABLE=0 -DMAGICKCORE_QUANTUM_DEPTH=16 \ + -lGraphicsMagick++ + +.PHONY: clean all + +all: + ${CXX} -o ./server ${CXXFLAGS} server.cc + +macos: + ${CXX} -o ./server -I /usr/local/include/ImageMagick-7 ${CXXFLAGS} server.cc + +clean: + @rm -r ./server diff --git a/hw1/readme.md b/hw1/readme.md new file mode 100644 index 0000000..1f8e286 --- /dev/null +++ b/hw1/readme.md @@ -0,0 +1,18 @@ +# Insidious Proxy +### Author: Claudio Maggioni + +## Sources and references used to write this program: + - [UniversalPizzoccheri](https://git.maggioni.xyz/maggicl/UniversalPizzoccheri) + (own work from high-school), used for code snippets on sockets + - cppreference.com and man 3, for documentation (as usual) + - [micro_proxy](http://acme.com/software/micro_proxy/), for general inspiration for the high + level implementation and code snippets for DNS queries. + +## Dependemcies: + - [GraphicsMagick++](http://www.graphicsmagick.org/project.html) for imagemagick bindings in + order to rotate the image. On macos, install with `brew install + graphicsmagick`. + +## Building: +On MacOS, run `make macos`. Otherwise use simply `make`. + diff --git a/server.cc b/hw1/server.cc similarity index 61% rename from server.cc rename to hw1/server.cc index 418fc63..da6f8a4 100644 --- a/server.cc +++ b/hw1/server.cc @@ -1,4 +1,22 @@ // vim: set ts=2 sw=2 et tw=80: +/* + * Insidious Proxy - Claudio Maggioni + * + * Sources and references used to write this program: + * - https://git.maggioni.xyz/maggicl/UniversalPizzoccheri (own work from + * high-school), used for code snippets on sockets + * - Cppreference.com and man 3, for documentation (as usual) + * - http://acme.com/software/micro_proxy/, for general inspiration for the high + * level implementation and code snippets for DNS queries. + * + * Dependemcies: + * - http://www.graphicsmagick.org/project.html for imagemagick bindings in + * order to rotate the image. On macos, install with 'brew install + * graphicsmagick'. + * + * Building: + * On MacOS, run 'make macos'. Otherwise use simply 'make'. + */ #include #include @@ -14,7 +32,6 @@ #include #include #include -#include #include using namespace std; @@ -239,7 +256,7 @@ bool is_chunk_end(vector& body) { * inspecting the HTTP headers), false is returned, otherwise returns true. */ bool fetch_body(FILE* in, vector& body, - const map headers) { + const map headers, bool strip_chunked) { bool chunked; size_t length; @@ -265,7 +282,7 @@ bool fetch_body(FILE* in, vector& body, for(size_t w = 0; w < length; w += r) { r = fread(buf, 1, (length - w) > BUFFER ? BUFFER : (length - w), in); if (r == -1) return false; - body.insert(end(body), begin(buf), end(buf)); + body.insert(end(body), buf, buf + r); } } else { // This was implemented before Prof. Carzaniga said chunked encoding is not @@ -288,7 +305,7 @@ bool fetch_body(FILE* in, vector& body, break; } - if (will_chunk_start && is_chunk_start(buf)) { + if (will_chunk_start && is_chunk_start(buf) && strip_chunked) { continue; } @@ -298,9 +315,13 @@ bool fetch_body(FILE* in, vector& body, will_chunk_start = is_chunk_end(body); } - body.insert(end(body), begin(buf), end(buf)); - body.push_back(fgetc(in)); // \r - body.push_back(fgetc(in)); // \n + char a = fgetc(in), b = fgetc(in); + + if (!strip_chunked) { + body.insert(end(body), begin(buf), end(buf)); + body.push_back(a); // \r + body.push_back(b); // \n + } } return true; @@ -343,85 +364,27 @@ void send_error(FILE* in, FILE* out, const char* protocol, const int status, } /** - * Parses the HTTP method name given as string and sets cURL options - * accordingly. Returns false if method is not supported on unknown, true - * otherwise - */ -bool set_curl_method(CURL* c, const char* method) { - if (!strcmp(method, "GET")) { - curl_easy_setopt(c, CURLOPT_HTTPGET, 1); - } else if (!strcmp(method, "HEAD")) { - curl_easy_setopt(c, CURLOPT_HTTPGET, 1); - curl_easy_setopt(c, CURLOPT_NOBODY, 1); - } else if (!strcmp(method, "POST")) { - curl_easy_setopt(c, CURLOPT_POST, 1); - } else if (!strcmp(method, "PUT")) { - curl_easy_setopt(c, CURLOPT_PUT, 1); - } else if (!strcmp(method, "DELETE")) { - curl_easy_setopt(c, CURLOPT_CUSTOMREQUEST, "DELETE"); - } else { - return false; - } - - return true; -} - -struct buffer { - size_t size; - uint8_t* data; -}; - -void buffer_init(struct buffer* self) { - self->size = 0; - self->data = (uint8_t*) malloc(8192); - if (self->data) { - self->data[0] = 0; - } -} - -size_t write_buffer(void *ptr, size_t size, size_t nmemb, - struct buffer* rbody) { - size_t index = rbody->size; - size_t n = size * nmemb; - - rbody->size += n; - - uint8_t* newdata = (uint8_t*) realloc(rbody->data, rbody->size + 1); - - if (!newdata) { - perror("reallocation of body buffer failed"); - if (rbody->data) free(rbody->data); - rbody->data = NULL; - return 0; - } else { - rbody->data = newdata; - } - - memcpy((rbody->data + index), ptr, n); - rbody->data[rbody->size] = '\0'; - - return size * nmemb; -} - -/** - * Converts url in a zero-terminated string for the host name. Port is retured + * Converts url in a zero-terminated string for the host name, copied in a + * pre-allocated char array given as copy_in. Port is returned * as integer, -1 on error */ -int find_host_port(char* url) { - char* i = url; +int find_host_port(const char* url, char* copy_in) { + const char* i = url; size_t c = 0; - while (*i != ':' && *i != '\0') { + while (*i != ':' && *i != '\0' && *i != '/') { if (c >= 256 || (!isalnum(*i) && *i != '-' && *i != '.')) return -1; + *copy_in = *i; + copy_in++; i++; c++; } if (c == 0) return -1; - *i = '\0'; + *copy_in = '\0'; i++; - if (*i == '\0') return 80; + if (*i == '\0' || *i == '/') return 80; unsigned p; if (sscanf(i, "%5u", &p) == 1) { @@ -436,7 +399,6 @@ struct forward { int out; }; - bool total_write(uint8_t* data, size_t n, int out) { for(size_t w = 0; w < n;) { ssize_t written = write(out, data + w, n - w); @@ -461,7 +423,9 @@ void* forwarder_thread(void* data) { } if (!total_write(buffer, r, f->out)) { - cout << "Closing CONNECT forwaredr" << endl; +#if DEBUG + cerr << "Closing CONNECT forwarder" << endl; +#endif return NULL; } } @@ -472,9 +436,12 @@ void* forwarder_thread(void* data) { /** * Returns a socket file descriptof of a newly opened socket to the given host. */ -int open_client_socket(FILE* in, FILE* out, const char* protocol, char* host) { +int open_client_socket(FILE* in, FILE* out, const char* protocol, + const char* host) { int port; - if ((port = find_host_port(host)) == -1) { + char hostname[257]; + + if ((port = find_host_port(host, hostname)) == -1) { send_error(in, out, protocol, 500, "Hostname parse error"); } @@ -483,7 +450,7 @@ int open_client_socket(FILE* in, FILE* out, const char* protocol, char* host) { send_error(in, out, protocol, 500, "TCP socket connection error"); } - struct hostent *he = gethostbyname(host); + struct hostent *he = gethostbyname(hostname); if (!he) { send_error(in, out, protocol, 404, "Unknown host"); } @@ -530,7 +497,9 @@ void handle_connect(FILE* in, FILE* out, const char* protocol, char* url, fprintf(out, "%s %d %s\r\n\r\n", protocol, 200, "Connection established"); fflush(out); - cout << "Connection established" << endl; +#if DEBUG + cerr << "CONNECT: Connection established" << endl; +#endif pthread_t ffrom; pthread_create(&ffrom, NULL, forwarder_thread, &from); @@ -540,29 +509,6 @@ void handle_connect(FILE* in, FILE* out, const char* protocol, char* url, pthread_join(ffrom, NULL); } -struct read_buffer { - const vector& body; - size_t index; -}; - -static size_t read_buffer(void *dest, size_t size, size_t nmemb, void *userp) -{ - struct read_buffer *wt = (struct read_buffer*) userp; - size_t buffer_size = size * nmemb; - size_t remaining = wt->body.size() - wt->index; - - if (buffer_size == wt->body.size()) { - return 0; - } - - size_t chunk_len = remaining > buffer_size ? buffer_size : remaining; - auto start = wt->body.begin() + wt->index; - - copy(start, start + chunk_len, (uint8_t*) dest); - wt->index += chunk_len; - return chunk_len; -} - void* request_thread(void* data) { int fd = *((int*) data); FILE* in = fdopen(dup(*((int*) data)), "r"); @@ -583,8 +529,10 @@ void* request_thread(void* data) { send_error(in, out, protocol, 400, "Bad request line"); } - cout << "METHOD: " << method << " URL: " << url << " PROTOCOL: " << protocol +#if DEBUG + cerr << "METHOD: " << method << " URL: " << url << " PROTOCOL: " << protocol << endl; +#endif if (!parse_headers(in, headers)) { send_error(in, out, protocol, 400, "Malformed header"); @@ -595,198 +543,148 @@ void* request_thread(void* data) { " URL (this is a proxy)"); } - cout << "BODY: " << endl; + bool has_body = fetch_body(in, body, headers, false); - // check if Content-Length is present and read Content-Length bytes - // check if Transfer-Encoding: chunked is present and wait for \r\n on a - // line - - if (has_body(method)) { - if (!fetch_body(in, body, headers)) { - send_error(in, out, protocol, 411, - "No Content-Length or Transfer-Encoding"); - } - } - - cout << "PARSED" << endl; +#if DEBUG + cerr << "has_body: " << has_body << endl; + cerr << "Request body parsed" << endl; +#endif if (!strcmp(method, "CONNECT")) { handle_connect(in, out, protocol, url, fd); break; } else { - // Delete Proxy-Connection header { auto i = headers.find("Proxy-Connection"); if (i != headers.end()) headers.erase(i); } - if (strncmp(url, "http://", 7) { - send_error(in. out, protocol, 400, "Protocol in URL not supported"); + if (strncmp(url, "http://", 7)) { + send_error(in, out, protocol, 400, "Protocol in URL not supported"); } char* host = url + 7; int serverfd = open_client_socket(in, out, protocol, host); - FILE* in = fdopen(dup(serverfd), "r"); - FILE* out = fdopen(dup(serverfd), "w"); + FILE* s_in = fdopen(dup(serverfd), "r"); + FILE* s_out = fdopen(dup(serverfd), "w"); - fprintf("%s %s %s\r\n", method, url, protocol); - for (auto i = headers.begin(); i != headers.end(); i++) { - fprintf("%s: %s\r\n", i->first.c_str(), i->second.c_str()); - } - - - /*struct buffer rhead; - struct buffer rbody; - buffer_init(&rhead); - buffer_init(&rbody); - - if(!rhead.data || !rbody.data) { - send_error(in, out, protocol, 500, "Failed to allocate response buffer"); - } - - CURL *curl; - curl = curl_easy_init(); - - if (!curl) { - send_error(in, out, protocol, 500, "Cannot init CURL"); - } - - if (!set_curl_method(curl, method)) { - send_error(in, out, protocol, 405, "Method not implemented"); - } - - curl_easy_setopt(curl, CURLOPT_URL, url); - - struct curl_slist *chunk = NULL; + fprintf(s_out, "%s %s %s\r\n", method, url, protocol); for (auto i = headers.begin(); i != headers.end(); i++) { - string header = i->first + ": " + i->second; - chunk = curl_slist_append(chunk, header.c_str()); + fprintf(s_out, "%s: %s\r\n", i->first.c_str(), i->second.c_str()); } - curl_easy_setopt(curl, CURLOPT_HTTPHEADER, chunk); + fprintf(s_out, "\r\n"); - if (has_body(method)) { - struct read_buffer r = { .body = body, .index = 0 }; - curl_easy_setopt(curl, CURLOPT_READFUNCTION, read_buffer); - curl_easy_setopt(curl, CURLOPT_READDATA, &r); - - chunk = curl_slist_append(chunk, "Transfer-Encoding: chunked"); - chunk = curl_slist_append(chunk, "Expect:"); - } - - curl_easy_setopt(curl, CURLOPT_HEADERFUNCTION, write_buffer); - curl_easy_setopt(curl, CURLOPT_HEADERDATA, &rhead); - curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_buffer); - curl_easy_setopt(curl, CURLOPT_WRITEDATA, &rbody); - CURLcode res = curl_easy_perform(curl); - if(res != CURLE_OK) { - fprintf(stderr, "curl_easy_perform() failed: %s\n", - curl_easy_strerror(res)); - send_error(in, out, protocol, 502, "Request to server failed"); - } else*/ { - char protocol_r[10]; - char message[8000]; - unsigned code; - - const char* image = NULL; - const char* const PNG = "PNG"; - const char* const JPEG = "JPEG"; - - { - cout << "RESPONSE: " << endl; - FILE* res_head = fmemopen(rhead.data, rhead.size, "r"); - - fscanf(res_head, "%10s %3u %8000s\r\n", protocol_r, &code, message); - - cout << "STATUS: " << code << " PROTOCOL: " << protocol_r << endl; - - headers.empty(); - parse_headers(res_head, headers); - - auto a = headers.find("Content-Type"); - if (a != headers.end()) { - if (a->second == "image/jpeg") image = JPEG; - else if (a->second == "image/png") image = PNG; - } + if (has_body) { + for (auto i = body.begin(); i < body.end(); i++) { + fputc(*i, s_out); } + } - cout << "image: " << (image ? image : "NULL") << endl; + fflush(s_out); + char protocol_r[10]; + char message[8000]; + unsigned code; + + const char* image = NULL; + const char* const PNG = "PNG"; + const char* const JPEG = "JPEG"; + + fscanf(s_in, "%10s %3u ", protocol_r, &code); + fgets(message, 8000, s_in); + message[strlen(message) - 2] = '\0'; + +#if DEBUG + cerr << "Response: STATUS: " << code << " MESSAGE: " << message << endl; +#endif + + headers.clear(); + parse_headers(s_in, headers); + + { + auto a = headers.find("Content-Type"); + if (a != headers.end()) { + if (a->second == "image/jpeg") image = JPEG; + else if (a->second == "image/png") image = PNG; + } + } + + body.clear(); + has_body = fetch_body(s_in, body, headers, true); + + fclose(s_in); + fclose(s_out); + close(serverfd); + + Magick::Blob output; + if (has_body && image) { + try { + Magick::Blob my_blob(&body[0], body.size()); + + Magick::Image to_rotate; - if (image) { try { - Magick::Blob my_blob(rbody.data, rbody.size); - Magick::Blob output; + to_rotate = Magick::Image(my_blob); + } catch(Magick::Warning& ignored) {} - Magick::Image to_rotate; + try { + to_rotate.magick(image); + } catch(Magick::Warning& ignored) {} - try { - to_rotate = Magick::Image(my_blob); - } catch(Magick::Warning& ignored) {} - - try { - to_rotate.magick(image); - } catch(Magick::Warning& ignored) {} - - try { - switch (alteration) { - case FLIP: to_rotate.flip(); break; - case LEFT: to_rotate.rotate(-90); break; - case RIGHT: to_rotate.rotate(90); break; - } - } catch(Magick::Warning& ignored) {} - - try { - to_rotate.write(&output); - } catch(Magick::Warning& ignored) {} - - fprintf(out, "%s %u %s\n", protocol_r, code, message); - - headers["Content-Length"] = to_string(output.length()); - headers["Connection"] = "keep-alive"; - for (auto i = headers.begin(); i != headers.end(); i++) { - string header = i->first + ": " + i->second + "\r\n"; - fprintf(out, "%s", header.c_str()); + try { + switch (alteration) { + case FLIP: to_rotate.flip(); break; + case LEFT: to_rotate.rotate(-90); break; + case RIGHT: to_rotate.rotate(90); break; } - fprintf(out, "\r\n"); - fflush(out); + } catch(Magick::Warning& ignored) {} - total_write((uint8_t*) output.data(), output.length(), fd); - } catch (Magick::Exception &error) { - cout << "Magick++ image conversion failed: " << error.what() - << endl; - send_error(in, out, protocol, 500, "Image conversion failed"); - } - } else { - total_write(rhead.data, rhead.size, fd); - total_write(rbody.data, rbody.size, fd); - fflush(out); + try { + to_rotate.write(&output); + } catch(Magick::Warning& ignored) {} + + fprintf(out, "%s %u %s\n", protocol_r, code, message); + + headers["Content-Length"] = to_string(output.length()); + } catch (Magick::Exception &error) { + cout << "Magick++ image conversion failed: " << error.what() + << endl; + send_error(in, out, protocol, 500, "Image conversion failed"); } + } else if (has_body) { + headers["Content-Length"] = to_string(body.size()); + } else { + headers["Content-Length"] = "0"; } - curl_easy_cleanup(curl); - curl_slist_free_all(chunk); - free(rhead.data); - free(rbody.data); - } + fprintf(out, "%s %u %s\n", protocol_r, code, message); - { - auto i = headers.find("Connection"); - if (i != headers.end() && i->second == "close") { - break; + headers["Connection"] = "keep-alive"; + for (auto i = headers.begin(); i != headers.end(); i++) { + string header = i->first + ": " + i->second + "\r\n"; + fprintf(out, "%s", header.c_str()); } + fprintf(out, "\r\n"); + fflush(out); + + if (has_body && image) { + total_write((uint8_t*) output.data(), output.length(), fd); + } else if (has_body) { + total_write(&body[0], body.size(), fd); + } + + fflush(out); } } cout << "closing data socket...\n"; fclose(in); - fflush(out); fclose(out); + close(fd); pthread_exit(NULL); } - -