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#include <asm-generic/errno-base.h>
#include <asm-generic/errno.h>
#include <netinet/in.h>
#include <stdio.h>
#include <stdio_ext.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/epoll.h>
#include <sys/sendfile.h>
#include <fcntl.h>
#include <unistd.h>
#include <poll.h>
#include <err.h>
#include <errno.h>
#include <pthread.h>
#include <stdarg.h>
void send_answer(FILE * f) {
fputs("HTTP/1.0 200 OK\n", f);
fputs("content-type: text/html\n\n", f);
fputs("<html>", f);
fputs("<head>", f);
fputs("<title>test</title>", f);
fputs("<style>label { display:block }</style>", f);
fputs("</head>", f);
fputs("<form action=\"/\" method=\"post\" enctype=\"multipart/form-data\">", f);
fputs("<label>Line1<br/>\n", f);
fputs("<textarea type=\"text\" name=\"text\"></textarea>", f);
fputs("</label><br/>\n", f);
fputs("<input type=\"file\" name=\"okay\" value=\"ok\" />", f);
fputs("<input type=\"submit\" name=\"okay\" value=\"ok\" />", f);
fputs("</form>", f);
fputs("</html>", f);
}
#define EWOULDBLOCK_DELAY 1000
#define READ_BUFFER_LENGTH 10
#define DEBUG_SLEEP_TIME 50000
static inline int verbose(const char * format, ...) {
va_list va; va_start(va, format); usleep(DEBUG_SLEEP_TIME); return vprintf(format, va);
}
void read_everything(FILE * f_r, FILE * output) {
const int read_buffer_length = READ_BUFFER_LENGTH;
char read_buffer[read_buffer_length];
for(size_t size = -2 ; ; size = fread(read_buffer, read_buffer_length, 1, f_r)) {
if(-2 == size || (-1 == size && EWOULDBLOCK == errno)) {
usleep(EWOULDBLOCK_DELAY); // try again a little later
continue;
} else if (1 != size) { // I expect one nmemb of data
break;
}
fwrite(read_buffer, read_buffer_length, 1, output);
}
fflush(output);
}
void header_next(const char * key, const char * value) {
// this sample function will be removed later
typedef struct {
const char * name;
const char * value;
} NameValue;
NameValue namevalue[] = {
{"Content-Type", NULL},
{"Content-Length", NULL}
};
for(int i=0; i < sizeof(namevalue) / sizeof(NameValue); i++) {
// printf("next name: %s\n", namevalue[i].name);
if(NULL == namevalue[i].value && 0 == strcasecmp(namevalue[i].name, key)) {
namevalue[i].value = value;
break;
}
}
}
void * next_customer(size_t new_socket) {
FILE * f_r = fdopen((size_t) new_socket, "r");
FILE * f_w = fdopen((size_t) new_socket, "w");
char * output_buffer = NULL;
size_t output_buffer_length = 0;
FILE * output = open_memstream(&output_buffer, &output_buffer_length);
verbose("\n\n########################################## Content Reader [%d]\n", f_r);
read_everything(f_r, output);
verbose("\n\n########################################## Content Parser");
// token parser...
const char * boundary = NULL;
size_t boundary_length = 0;
char * search = NULL;
char * key = output_buffer;
char * saveptr = NULL;
char * content_start = NULL;
char * content_end = NULL;
while(key ? key[0] != '\0' : 1) {
verbose("> [!] Next iteration with search '%s'\n", search);
for(char *
token = strtok_r(NULL == saveptr ? output_buffer : saveptr, NULL == search ? "\n\r" : search, &saveptr);
token != NULL;
token = strtok_r(NULL, search, &saveptr))
{
if(!search) { // first round: HTTP status code
verbose("> First Iteration: HTTP sanity check of: %s\n", token);
search = ":";
continue;
}
if(!key) {
search = "\r\n"; // we found a key and expect the value to be between here and EOL
key = &token[strspn(token, search)]; // also remove leading spaces
if(0 == strncmp(token, "\n\r\n", 3)
|| 0 == strncmp(token, "\n\n", 2)) {
search = "\r\n";
break;
}
} else { // value
token += strspn(token, ": ");
const char * value = token;
const char pattern[] = "multipart/form-data; boundary=";
if(!boundary && strstr(key, "Content-Type") && strncmp(value, pattern, sizeof(pattern))) {
boundary = &value[sizeof(pattern) + strspn(&value[sizeof(pattern)], "-")];
boundary_length = strlen(boundary);
verbose("> [!] boundary detected '%s' ", boundary);
}
header_next(key, value);
verbose("> [%ld] \"%s\" :: \"%s\"\n", key - output_buffer, key, value); fflush(stdout);
search = ":";
key = NULL;
}
}
if(!key)
break;
// printf("We are now here: %ld\n", key - output_buffer);
verbose("We are now here: %s\n", key);
// jump over the content...
content_start = key;
while((key = memchr(key, '\n', output_buffer_length - (key - output_buffer)))) {
if(!key) {
verbose("out at %p\n", key);
break;
} else {
key++;
}
if(key[0] == '-') {
if(0 == strncmp(&key[strspn(key, "-")], boundary, boundary_length)) {
verbose("> boundary found.");
if(key[-1] == '\n') key--;
if(key[-1] == '\r') key--;
content_end = key;
key += strspn(key, "\r\n-");
key += boundary_length;
key += strspn(key, "\r\n");
saveptr = key;
key = NULL;
search = ":";
break;
}
}
}
verbose("content is %p - %p = %ld in size\n", content_end, content_start, content_end - content_start);
if(content_end - content_start > 1000) {
FILE * f_w = fopen("/tmp/test.gif", "w");
fwrite(content_start, content_end - content_start, 1, f_w);
fclose(f_w);
puts("FILE WRITTEN");
}
// printf("We have gone to %ld\n", key - output_buffer); fflush(stdout);
if(key && key[0] == '\0') // final boundary reached?
break;
// usleep(100000);
}
verbose("> sending answer...");
send_answer(f_w);
fclose(f_w);
fclose(f_r);
verbose("> answer sent.");
return NULL;
}
int serve(int server_fd)
{
struct sockaddr_in address;
socklen_t address_len = sizeof(address);
verbose("waiting for connections on server file descriptor %d", server_fd);
size_t new_socket = -1;
while(-1 != (new_socket = accept(server_fd, (struct sockaddr*) &address, &address_len)))
{
verbose("> Client %ld is connected via port %d", new_socket, address.sin_port);
// set non blocking mode...
fcntl(
(size_t) new_socket,
F_SETFL,
fcntl((size_t) new_socket, F_GETFL) | O_NONBLOCK
);
next_customer(new_socket);
/*
if(fork()) {
close(new_socket);
} else {
close(server_fd); // give the server free
next_customer(new_socket);
shutdown(new_socket, SHUT_RDWR);
exit(0);
}
*/
// pthread_t thread_id;
// pthread_create(&thread_id, NULL, next_customer, (void*) new_socket);
// pthread_join(thread_id, NULL);
}
err(errno, "error serving");
}
#define PORT 8080
int main(int argc, char const *argv[])
{
int server_fd = -1, opt = 1;
struct sockaddr_in address = {
.sin_family = AF_INET,
.sin_addr.s_addr = INADDR_ANY,
.sin_port = htons(PORT)
};
// I <3 C
0 == (server_fd = socket(AF_INET, SOCK_STREAM, 0))
? err(errno, NULL)
: setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR | SO_REUSEPORT, &opt, sizeof(opt))
? err(errno, "setsockopt failed on socket with fileno %d", server_fd)
: bind(server_fd, (struct sockaddr*) &address, sizeof(address))
? err(errno, NULL)
: listen(server_fd, SOMAXCONN)
? err(errno, NULL)
: serve(server_fd)
? err(errno, NULL)
: exit(EXIT_SUCCESS)
;
return EXIT_FAILURE;
}
// void * next_customer_old(int new_socket)
// {
// char *hello = "Hello from server";
// char buffer[1024] = {0};
// int valread = read(new_socket, buffer, 1024);
// printf("%s %d\n", buffer, valread);
//
// send(new_socket, hello, strlen(hello), 0);
//
// printf("Hello message sent\n");
// return NULL;
// }
// IDEA ...
//
// #define FOREACH_HEADER(HEADER) \
// HEADER("Content-Type: multipart/form-data; boundary=")
// #define GENERATE_HEADERS(H) sizeof(H), H
//
// typedef struct {
// const int length;
// const char * string;
// } length_value;
//
// const length_value headers[] = {
// FOREACH_HEADER(GENERATE_HEADERS)
// };
//
// READ WITH recv ...
/*
for(size_t size = -1 ; ; (size = recv(new_socket, read_buffer, read_buffer_length, 0))) {
if(-1 == size) {
usleep(10000);
printf("size: %ld\n", size);
if(EWOULDBLOCK == errno){
continue;
} else if (size == 0 || size < read_buffer_length) {
break;
}
} else {
read_buffer[size] = '\0';
fwrite(read_buffer, size, 1, output);
fwrite(read_buffer, size, 1, stdout);
// if(output_buffer_length > 4
// && (strspn(&output_buffer[output_buffer_length - 2], "\n") == 2
// || strspn(&output_buffer[output_buffer_length - 4], "\r\n") == 4))
// break;
}
}*/
// fully working implementation...
/*
void * next_customer(void * new_socket) {
const int MAX_HEADER_LINE_LENGTH = 1024;
const int MAX_BOUNDARY_LENGTH = 64;
char boundary[64] = {0};
int boundary_size = 0;
char current_name[64] = {0};
usleep(100); // wait to avoid poll, epoll or evil select
char * output_buffer = NULL;
size_t output_buffer_length = 0;
FILE * output = open_memstream(&output_buffer, &output_buffer_length);
FILE * f = fdopen((size_t) new_socket, "r");
char buffer[MAX_HEADER_LINE_LENGTH];
char * s = NULL;
while(1) {
// printf("[errno: %d] %s", errno, buffer);
s = fgets(buffer, MAX_HEADER_LINE_LENGTH, f);
if(boundary[0] != '\0' && buffer[0] == '-') { // first char minus. could be a new chunk of post data
int i = 0;
for(i = 1; i < MAX_HEADER_LINE_LENGTH; i++) {
if(buffer[i] != '-') { // skip all minus
if(0 == strncmp(&buffer[i], boundary, boundary_size)) {
fflush(output);
printf("> name='%s' value='%*s'\n", current_name, (int) output_buffer_length, output_buffer);
setenv(current_name, output_buffer, 0);
current_name[0] = '\0';
rewind(output);
i = 0;
puts("================================================================================");
}
break;
}
}
if (i == 0) continue;
}
if(!s || strspn(buffer, "\n\r") > 0) { // either LF or CR/LF (windows)
puts("END HEADER\n");
// s != NULL ? break : continue;
if(!s) break; else continue; // either eof or only end of (chunk-)header
}
const char header_multipart[] = "Content-Type: multipart/form-data; boundary=";
if (!boundary[0] && 0 == strncasecmp(buffer, header_multipart, sizeof(header_multipart) - 1)) {
// we could potentially optimize this part with strspn and moving the buffer point, why not?
for(int i=sizeof(header_multipart); i<MAX_HEADER_LINE_LENGTH; i++)
if(buffer[i] != '-') {
strncpy(boundary, &buffer[i], 64);
boundary_size = strnlen(boundary, 64);
boundary[boundary_size] = '\0';
printf("> [%s] %s\n", header_multipart, boundary);
break;
}
continue;
}
const char header_disposition[] = "Content-Disposition: form-data; ";
if (boundary[0] && 0 == strncasecmp(header_disposition, buffer, sizeof(header_disposition) - 1)) {
printf("> %s :: %s\n", header_disposition, buffer);
const char header_disposition_name[] = "name=\"";
s = strstr(&buffer[sizeof(header_disposition) - 1], header_disposition_name);
if(s) {
s += sizeof(header_disposition_name) - 1;
s[strcspn(s, "\"")] = '\0';
strncpy(current_name, s, 64);
printf("> /%s.*%s/ :: \"%s\"\n", header_disposition, header_disposition_name, s);
} else {
warnx("string not found in \"%s\".", &buffer[sizeof(header_disposition)]);
}
continue;
}// else { printf("FUCK: %*s [%d/%ld]\n", (int) sizeof(header_disposition), buffer, strncasecmp(header_disposition, buffer, sizeof(header_disposition)), sizeof(header_disposition)); }
printf("> [unknown] %s", buffer);
fputs(buffer, output);
// I think another if could now search for "Content-Disposition: form-data; " and store the remaining fields
// somewhere, e.g. name="okay"; filename="1.gif". Also there may also be a content-type per chunk, which we
// could also add and erase, where I have currently NEXT CHUNK.
// After that the text output (printf("%s", buffer)) will only contain content without headers, so that printf
// can then be replaced with some fwrite to a memstream and we are done :)
}
puts("> sending answer...");
send_answer(new_socket);
puts("> answer sent.");
return NULL;
}
*/
// vim: shiftwidth=2 tabstop=2 number
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