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- /*
- * Slitheen - a decoy routing system for censorship resistance
- * Copyright (C) 2017 Cecylia Bocovich (cbocovic@uwaterloo.ca)
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, version 3.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- *
- * Additional permission under GNU GPL version 3 section 7
- *
- * If you modify this Program, or any covered work, by linking or combining
- * it with the OpenSSL library (or a modified version of that library),
- * containing parts covered by the terms of the OpenSSL Licence and the
- * SSLeay license, the licensors of this Program grant you additional
- * permission to convey the resulting work. Corresponding Source for a
- * non-source form of such a combination shall include the source code
- * for the parts of the OpenSSL library used as well as that of the covered
- * work.
- */
- #include <stdio.h>
- #include <stdlib.h>
- #include <unistd.h>
- #include <stdint.h>
- #include <errno.h>
- #include <string.h>
- #include <sys/socket.h>
- #include <sys/types.h>
- #include <sys/stat.h>
- #include <netinet/in.h>
- #include <netdb.h>
- #include <pthread.h>
- #include <fcntl.h>
- #include <arpa/inet.h>
- #include <openssl/bio.h>
- #include <openssl/evp.h>
- #include <openssl/buffer.h>
- #include <openssl/rand.h>
- #include "socks5proxy.h"
- #include "crypto.h"
- #include "tagging.h"
- static connection_table *connections;
- int main(void){
- int listen_socket;
-
- struct sockaddr_in address;
- struct sockaddr_in remote_addr;
- socklen_t addr_size;
- mkfifo("OUS_out", 0666);
- //generate Slitheen ID using Telex tagging method
- uint8_t slitheen_id[SLITHEEN_ID_LEN];
- uint8_t shared_secret[16];
- generate_slitheen_id(slitheen_id, shared_secret);
- //RAND_bytes(slitheen_id, SLITHEEN_ID_LEN);
- printf("Randomly generated slitheen id: ");
- int i;
- for(i=0; i< SLITHEEN_ID_LEN; i++){
- printf("%02x ", slitheen_id[i]);
- }
- printf("\n");
- // Calculate super encryption keys
- generate_super_keys(shared_secret);
- //b64 encode slitheen ID
- char *encoded_bytes;
- BUF_MEM *buffer_ptr;
- BIO *bio, *b64;
- b64 = BIO_new(BIO_f_base64());
- bio = BIO_new(BIO_s_mem());
- bio = BIO_push(b64, bio);
- BIO_set_flags(bio, BIO_FLAGS_BASE64_NO_NL);
- BIO_write(bio, slitheen_id, SLITHEEN_ID_LEN);
- BIO_flush(bio);
- BIO_get_mem_ptr(bio, &buffer_ptr);
- BIO_set_close(bio, BIO_NOCLOSE);
- BIO_free_all(bio);
- encoded_bytes = (*buffer_ptr).data;
- encoded_bytes[(*buffer_ptr).length] = '\0';
- //give encoded slitheen ID to ous
- struct sockaddr_in ous_addr;
- ous_addr.sin_family = AF_INET;
- inet_pton(AF_INET, "127.0.0.1", &(ous_addr.sin_addr));
- ous_addr.sin_port = htons(8888);
- int32_t ous_in = socket(AF_INET, SOCK_STREAM, 0);
- if(ous_in < 0){
- printf("Failed to make ous_in socket\n");
- return 1;
- }
- int32_t error = connect(ous_in, (struct sockaddr *) &ous_addr, sizeof (struct sockaddr));
- if(error < 0){
- printf("Error connecting\n");
- return 1;
- }
- char *message = calloc(1, BUFSIZ);
- sprintf(message, "POST / HTTP/1.1\r\nContent-Length: %zd\r\n\r\n%s ", strlen(encoded_bytes), encoded_bytes);
- int32_t bytes_sent = send(ous_in, message, strlen(message), 0);
- printf("Wrote %d bytes to OUS_in:\n %s\n", bytes_sent, message);
- free(message);
- /* Spawn process to listen for incoming data from OUS
- int32_t demux_pipe[2];
- if(pipe(demux_pipe) < 0){
- printf("Failed to create pipe for new thread\n");
- return 1;
- }*/
- connections = calloc(1, sizeof(connection_table));
- connections->first = NULL;
-
- pthread_t *demux_thread = calloc(1, sizeof(pthread_t));
- pthread_create(demux_thread, NULL, demultiplex_data, NULL);
- if (!(listen_socket = socket(AF_INET, SOCK_STREAM, 0))){
- printf("Error creating socket\n");
- fflush(stdout);
- return 1;
- }
- address.sin_family = AF_INET;
- address.sin_addr.s_addr = INADDR_ANY;
- address.sin_port = htons(1080);
- int enable = 1;
- if (setsockopt(listen_socket, SOL_SOCKET, SO_REUSEADDR, &enable, sizeof(enable)) <0 ){
- printf("Error setting sockopt\n");
- return 1;
- }
- if(bind(listen_socket, (struct sockaddr *) &address, sizeof(address))){
- printf("Error binding socket\n");
- fflush(stdout);
- return 1;
- }
- if(listen(listen_socket, 10) < 0){
- printf("Error listening\n");
- fflush(stdout);
- close(listen_socket);
- exit(1);
- }
- uint8_t last_id = 1;
- printf("Ready for listening\n");
- for(;;){
- addr_size = sizeof(remote_addr);
- int new_socket;
- new_socket = accept(listen_socket, (struct sockaddr *) &remote_addr,
- &addr_size);
- if(new_socket < 0){
- perror("accept");
- exit(1);
- }
- printf("New connection\n");
- //assign a new stream_id and create a pipe for the session
- connection *new_conn = calloc(1, sizeof(connection));
- new_conn->stream_id = last_id++;
-
- int32_t pipefd[2];
- if(pipe(pipefd) < 0){
- printf("Failed to create pipe\n");
- continue;
- }
- new_conn->pipe_fd = pipefd[1];
- new_conn->next = NULL;
-
- if(connections->first == NULL){
- connections->first = new_conn;
- printf("Added first connection with id: %d\n", new_conn->stream_id);
- fflush(stdout);
- } else {
- connection *last = connections->first;
- while(last->next != NULL){
- last = last->next;
- }
- last->next = new_conn;
- printf("Added connection with id: %d at %p\n", new_conn->stream_id, last->next);
- fflush(stdout);
- }
- int pid = fork();
- if(pid == 0){ //child
- close(listen_socket);
- proxy_data(new_socket, new_conn->stream_id, pipefd[0]);
- exit(0);
- }
- close(new_socket);
-
- }
- return 0;
- }
- //continuously read from the socket and look for a CONNECT message
- int proxy_data(int sockfd, uint16_t stream_id, int32_t ous_out){
- uint8_t *buffer = calloc(1, BUFSIZ);
- uint8_t *response = calloc(1, BUFSIZ);
- int32_t i;
-
- int bytes_read = recv(sockfd, buffer, BUFSIZ-1, 0);
- if (bytes_read < 0){
- printf("Error reading from socket (fd = %d)\n", sockfd);
- fflush(stdout);
- goto err;
- }
- #ifdef DEBUG
- printf("Received %d bytes (id %d):\n", bytes_read, stream_id);
- for(i=0; i< bytes_read; i++){
- printf("%02x ", buffer[i]);
- }
- printf("\n");
- fflush(stdout);
- #endif
- //Respond to methods negotiation
- struct socks_method_req *clnt_meth = (struct socks_method_req *) buffer;
- uint8_t *p = buffer + 2;
- if(clnt_meth->version != 0x05){
- printf("Client supplied invalid version: %02x\n", clnt_meth->version);
- fflush(stdout);
- goto err;
- }
- int responded = 0;
- int bytes_sent;
- for(i=0; i< clnt_meth->num_methods; i++){
- if(p[0] == 0x00){//send response with METH= 0x00
- response[0] = 0x05;
- response[1] = 0x00;
- send(sockfd, response, 2, 0);
- responded = 1;
- }
- p++;
- }
- if(!responded){//respond with METH= 0xFF
- response[0] = 0x05;
- response[1] = 0xFF;
- send(sockfd, response, 2, 0);
- goto err;
- }
- //Now wait for a connect request
- bytes_read = recv(sockfd, buffer, BUFSIZ-1, 0);
- if (bytes_read < 0){
- printf("Error reading from socket\n");
- fflush(stdout);
- goto err;
- }
- #ifdef DEBUG
- printf("Received %d bytes (id %d):\n", bytes_read, stream_id);
- for(i=0; i< bytes_read; i++){
- printf("%02x ", buffer[i]);
- }
- printf("\n");
- fflush(stdout);
- #endif
- //Now respond
- response[0] = 0x05;
- response[1] = 0x00;
- response[2] = 0x00;
- response[3] = 0x01;
- *((uint32_t *) (response + 4)) = 0;
- *((uint16_t *) (response + 8)) = 0;
- send(sockfd, response, 10, 0);
- //wait for first upstream bytes
- bytes_read += recv(sockfd, buffer+bytes_read, BUFSIZ-bytes_read-3, 0);
- if (bytes_read < 0){
- printf("Error reading from socket\n");
- fflush(stdout);
- goto err;
- }
- #ifdef DEBUG_UPSTREAM
- printf("Received %d bytes (id %d):\n", bytes_read, stream_id);
- for(i=0; i< bytes_read; i++){
- printf("%02x ", buffer[i]);
- }
- printf("\n");
- fflush(stdout);
- #endif
- //pre-pend stream_id and length
- memmove(buffer+sizeof(struct slitheen_up_hdr), buffer, bytes_read+1);
- struct slitheen_up_hdr *up_hdr = (struct slitheen_up_hdr *) buffer;
- up_hdr->stream_id = stream_id;
- up_hdr->len = htons(bytes_read);
- bytes_read+= sizeof(struct slitheen_up_hdr);
- //encode bytes for safe transport (b64)
- const char *encoded_bytes;
- BUF_MEM *buffer_ptr;
- BIO *bio, *b64;
- b64 = BIO_new(BIO_f_base64());
- bio = BIO_new(BIO_s_mem());
- bio = BIO_push(b64, bio);
- BIO_set_flags(bio, BIO_FLAGS_BASE64_NO_NL);
- BIO_write(bio, buffer, bytes_read);
- BIO_flush(bio);
- BIO_get_mem_ptr(bio, &buffer_ptr);
- BIO_set_close(bio, BIO_NOCLOSE);
- BIO_free_all(bio);
- encoded_bytes = (*buffer_ptr).data;
- struct sockaddr_in ous_addr;
- ous_addr.sin_family = AF_INET;
- inet_pton(AF_INET, "127.0.0.1", &(ous_addr.sin_addr));
- ous_addr.sin_port = htons(8888);
- int32_t ous_in = socket(AF_INET, SOCK_STREAM, 0);
- if(ous_in < 0){
- printf("Failed to make ous_in socket\n");
- goto err;
- }
- int32_t error = connect(ous_in, (struct sockaddr *) &ous_addr, sizeof (struct sockaddr));
- if(error < 0){
- printf("Error connecting\n");
- goto err;
- }
- char *message = calloc(1, BUFSIZ);
- sprintf(message, "POST / HTTP/1.1\r\nContent-Length: %zd\r\n\r\n%s ", strlen(encoded_bytes)+1, encoded_bytes);
- bytes_sent = send(ous_in, message, strlen(message), 0);
- #ifdef DEBUG_UPSTREAM
- printf("Wrote %d bytes to OUS_in: %s\n", bytes_sent, message);
- #endif
- if(bytes_sent < 0){
- printf("Error writing to websocket\n");
- fflush(stdout);
- goto err;
- } else {
- close(ous_in);
- }
- p = buffer+sizeof(struct slitheen_up_hdr);
- #ifdef DEBUG_UPSTREAM
- for(i=0; i< bytes_read; i++){
- printf("%02x ", p[i]);
- }
- printf("\n");
- fflush(stdout);
- #endif
- struct socks_req *clnt_req = (struct socks_req *) p;
- p += 4;
- //see if it's a connect request
- if(clnt_req->cmd != 0x01){
- printf("Error: issued a non-connect command\n");
- fflush(stdout);
- goto err;
- }
- //now select on pipe (for downstream data) and the socket (for upstream data)
- for(;;){
- fd_set readfds;
- fd_set writefds;
- int32_t nfds = (sockfd > ous_out) ? sockfd +1 : ous_out + 1;
- FD_ZERO(&readfds);
- FD_ZERO(&writefds);
- FD_SET(sockfd, &readfds);
- FD_SET(ous_out, &readfds);
- FD_SET(sockfd, &writefds);
- if(select(nfds, &readfds, &writefds, NULL, NULL) <0){
- printf("Select error\n");
- fflush(stdout);
- continue;
- }
- if(FD_ISSET(sockfd, &readfds)){// && FD_ISSET(ous_in, &writefds)){
- bytes_read = recv(sockfd, buffer, BUFSIZ-1, 0);
- if (bytes_read < 0){
- printf("Error reading from socket (in for loop)\n");
- fflush(stdout);
- goto err;
- }
- if(bytes_read == 0){
- //socket is closed
- printf("Closing connection for stream %d sockfd.\n", stream_id);
- fflush(stdout);
- //Send close message to slitheen proxy
- up_hdr = (struct slitheen_up_hdr *) buffer;
- up_hdr->stream_id = stream_id;
- up_hdr->len = 0;
- bio = BIO_new(BIO_s_mem());
- b64 = BIO_new(BIO_f_base64());
- bio = BIO_push(b64, bio);
- BIO_set_flags(bio, BIO_FLAGS_BASE64_NO_NL);
- BIO_write(bio, buffer, 20);
- BIO_flush(bio);
- BIO_get_mem_ptr(bio, &buffer_ptr);
- encoded_bytes = (*buffer_ptr).data;
- BIO_set_close(bio, BIO_NOCLOSE);
- BIO_free_all(bio);
- uint8_t *ebytes = calloc(1, (*buffer_ptr).length+1);
- memcpy(ebytes, (*buffer_ptr).data, (*buffer_ptr).length);
- ebytes[(*buffer_ptr).length] = '\0';
- ous_in = socket(AF_INET, SOCK_STREAM, 0);
- if(ous_in < 0){
- printf("Failed to make ous_in socket\n");
- fflush(stdout);
- goto err;
- }
- error = connect(ous_in, (struct sockaddr *) &ous_addr, sizeof (struct sockaddr));
- if(error < 0){
- printf("Error connecting\n");
- fflush(stdout);
- goto err;
- }
- sprintf(message, "POST / HTTP/1.1\r\nContent-Length: %zd\r\n\r\n%s ",
- strlen( (char *)ebytes)+1, ebytes);
- free(ebytes);
- bytes_sent = send(ous_in, message, strlen(message), 0);
- printf("Closing message: %s\n", message);
- close(ous_in);
- goto err;
-
- }
- if(bytes_read > 0){
- #ifdef DEBUG_UPSTREAM
- printf("Received %d data bytes from sockfd (id %d):\n", bytes_read, stream_id);
- for(i=0; i< bytes_read; i++){
- printf("%02x ", buffer[i]);
- }
- printf("\n");
- printf("%s\n", buffer);
- fflush(stdout);
- #endif
- memmove(buffer+sizeof(struct slitheen_up_hdr), buffer, bytes_read);
- up_hdr = (struct slitheen_up_hdr *) buffer;
- up_hdr->stream_id = stream_id;
- up_hdr->len = htons(bytes_read);
- bytes_read+= sizeof(struct slitheen_up_hdr);
- bio = BIO_new(BIO_s_mem());
- b64 = BIO_new(BIO_f_base64());
- bio = BIO_push(b64, bio);
- BIO_set_flags(bio, BIO_FLAGS_BASE64_NO_NL);
- BIO_write(bio, buffer, bytes_read);
- BIO_flush(bio);
- BIO_get_mem_ptr(bio, &buffer_ptr);
- BIO_set_close(bio, BIO_NOCLOSE);
- BIO_free_all(bio);
- encoded_bytes = (*buffer_ptr).data;
-
- ous_in = socket(AF_INET, SOCK_STREAM, 0);
- if(ous_in < 0){
- printf("Failed to make ous_in socket\n");
- return 1;
- }
- error = connect(ous_in, (struct sockaddr *) &ous_addr, sizeof (struct sockaddr));
- if(error < 0){
- printf("Error connecting\n");
- return 1;
- }
- sprintf(message, "POST / HTTP/1.1\r\nContent-Length: %zd\r\n\r\n%s ",
- strlen(encoded_bytes)+1, encoded_bytes);
- bytes_sent = send(ous_in, message, strlen(message), 0);
- #ifdef DEBUG_UPSTREAM
- printf("Sent to OUS (%d bytes):%s\n",bytes_sent, message);
- #endif
- close(ous_in);
- }
- } else if(FD_ISSET(ous_out, &readfds) && FD_ISSET(sockfd, &writefds)){
- bytes_read = read(ous_out, buffer, BUFSIZ-1);
- if (bytes_read <= 0){
- printf("Error reading from ous_out (in for loop)\n");
- fflush(stdout);
- goto err;
- }
- if(bytes_read > 0){
- #ifdef DEBUG_DOWNSTREAM
- printf("Stream id %d received %d bytes from ous_out:\n", stream_id, bytes_read);
- for(i=0; i< bytes_read; i++){
- printf("%02x ", buffer[i]);
- }
- printf("\n");
- printf("%s\n", buffer);
- fflush(stdout);
- #endif
- bytes_sent = send(sockfd, buffer, bytes_read, 0);
- if(bytes_sent <= 0){
- printf("Error sending bytes to browser for stream id %d\n", stream_id);
- }
-
- #ifdef DEBUG_DOWNSTREAM
- printf("Sent to browser (%d bytes from stream id %d):\n", bytes_sent, stream_id);
- for(i=0; i< bytes_sent; i++){
- printf("%02x ", buffer[i]);
- }
- printf("\n");
- fflush(stdout);
- #endif
- }
- }
- }
- err:
- //should also remove stream from table
- close(sockfd);
- free(buffer);
- free(response);
- exit(0);
- }
- /* Read blocks of covert data from OUS_out. Determine the stream id and the length of
- * the block and then write the data to the correct thread to be passed to the browser
- */
- void *demultiplex_data(){
- int32_t buffer_len = BUFSIZ;
- uint8_t *buffer = calloc(1, buffer_len);
- uint8_t *p;
- printf("Opening OUS_out... ");
- int32_t ous_fd = open("OUS_out", O_RDONLY);
- printf("done.\n");
- uint8_t *partial_block = NULL;
- uint32_t partial_block_len = 0;
- uint32_t resource_remaining = 0;
- uint64_t expected_next_count = 1;
- data_block *saved_data = NULL;
- for(;;){
- int32_t bytes_read = read(ous_fd, buffer, buffer_len-partial_block_len);
-
- if(bytes_read > 0){
- int32_t bytes_remaining = bytes_read;
- p = buffer;
- //didn't read a full slitheen block last time
- if(partial_block_len > 0){
- //process first part of slitheen info
- memmove(buffer+partial_block_len, buffer, bytes_read);
- memcpy(buffer, partial_block, partial_block_len);
- bytes_remaining += partial_block_len;
- free(partial_block);
- partial_block = NULL;
- partial_block_len = 0;
- }
- while(bytes_remaining > 0){
- if(resource_remaining <= 0){//we're at a new resource
- //the first value for a new resource will be the resource length,
- //followed by a newline
- uint8_t *end_ptr;
- resource_remaining = strtol((const char *) p, (char **) &end_ptr, 10);
- #ifdef DEBUG_PARSE
- printf("Starting new resource of len %d bytes\n", resource_remaining);
- printf("Resource len bytes:\n");
- int i;
- for(i=0; i< (end_ptr - p) + 1; i++){
- printf("%02x ", ((const char *) p)[i]);
- }
- printf("\n");
- #endif
- if(resource_remaining == 0){
- bytes_remaining -= (end_ptr - p) + 1;
- p += (end_ptr - p) + 1;
- } else {
- bytes_remaining -= (end_ptr - p) + 1;
- p += (end_ptr - p) + 1;
- }
- continue;
- }
- if(resource_remaining < SLITHEEN_HEADER_LEN){
- printf("ERROR: Resource remaining doesn't fit header len.\n");
- resource_remaining = 0;
- bytes_remaining = 0;
- break;
- }
- if(bytes_remaining < SLITHEEN_HEADER_LEN){
- #ifdef DEBUG_PARSE
- printf("Partial header: ");
- int i;
- for(i = 0; i< bytes_remaining; i++){
- printf("%02x ", p[i]);
- }
- printf("\n");
- #endif
- if(partial_block != NULL) printf("UH OH (PB)\n");
- partial_block = calloc(1, bytes_remaining);
- memcpy(partial_block, p, bytes_remaining);
- partial_block_len = bytes_remaining;
- bytes_remaining = 0;
- break;
- }
- //decrypt header to see if we have entire block
- uint8_t *tmp_header = malloc(SLITHEEN_HEADER_LEN);
- memcpy(tmp_header, p, SLITHEEN_HEADER_LEN);
- peek_header(tmp_header);
- struct slitheen_hdr *sl_hdr = (struct slitheen_hdr *) tmp_header;
- //first see if sl_hdr corresponds to a valid stream. If not, ignore rest of read bytes
- #ifdef DEBUG_PARSE
- printf("Slitheen header:\n");
- int i;
- for(i = 0; i< SLITHEEN_HEADER_LEN; i++){
- printf("%02x ", tmp_header[i]);
- }
- printf("\n");
- #endif
- if(ntohs(sl_hdr->len) > resource_remaining){
- printf("ERROR: slitheen block doesn't fit in resource remaining!\n");
- resource_remaining = 0;
- bytes_remaining = 0;
- break;
- }
- if(ntohs(sl_hdr->len) > bytes_remaining){
- if(partial_block != NULL) printf("UH OH (PB)\n");
- partial_block = calloc(1, ntohs(sl_hdr->len));
- memcpy(partial_block, p, bytes_remaining);
- partial_block_len = bytes_remaining;
- bytes_remaining = 0;
- free(tmp_header);
- break;
- }
- super_decrypt(p);
- sl_hdr = (struct slitheen_hdr *) p;
- free(tmp_header);
- p += SLITHEEN_HEADER_LEN;
- bytes_remaining -= SLITHEEN_HEADER_LEN;
- resource_remaining -= SLITHEEN_HEADER_LEN;
- if((!sl_hdr->len) && (sl_hdr->garbage)){
- #ifdef DEBUG_PARSE
- printf("%d Garbage bytes\n", ntohs(sl_hdr->garbage));
- #endif
- p += ntohs(sl_hdr->garbage);
- bytes_remaining -= ntohs(sl_hdr->garbage);
- resource_remaining -= ntohs(sl_hdr->garbage);
- continue;
- }
- int32_t pipe_fd =-1;
- if(connections->first == NULL){
- printf("Error: there are no connections\n");
- } else {
- connection *last = connections->first;
- if (last->stream_id == sl_hdr->stream_id){
- pipe_fd = last->pipe_fd;
- }
- while(last->next != NULL){
- last = last->next;
- if (last->stream_id == sl_hdr->stream_id){
- pipe_fd = last->pipe_fd;
- }
- }
- }
-
- if(pipe_fd == -1){
- printf("No stream id exists. Possibly invalid header\n");
- break;
- }
-
- #ifdef DEBUG_PARSE
- printf("Received information for stream id: %d of length: %u\n", sl_hdr->stream_id, ntohs(sl_hdr->len));
- #endif
- //figure out how much to skip
- int32_t padding = 0;
- if(ntohs(sl_hdr->len) %16){
- padding = 16 - ntohs(sl_hdr->len)%16;
- }
- p += 16; //IV
- //check counter to see if we are missing data
- if(sl_hdr->counter > expected_next_count){
- //save any future data
- printf("Received header with count %lu. Expected count %lu.\n",
- sl_hdr->counter, expected_next_count);
- if((saved_data == NULL) || (saved_data->count > sl_hdr->counter)){
- data_block *new_block = malloc(sizeof(data_block));
- new_block->count = sl_hdr->counter;
- new_block->len = ntohs(sl_hdr->len);
- new_block->data = malloc(ntohs(sl_hdr->len));
- memcpy(new_block->data, p, ntohs(sl_hdr->len));
-
- new_block->pipe_fd = pipe_fd;
- new_block->next = saved_data;
- saved_data = new_block;
- } else {
- data_block *last = saved_data;
- while((last->next != NULL) && (last->next->count < sl_hdr->counter)){
- last = last->next;
- }
- data_block *new_block = malloc(sizeof(data_block));
- new_block->count = sl_hdr->counter;
- new_block->len = ntohs(sl_hdr->len);
- new_block->data = malloc(ntohs(sl_hdr->len));
- memcpy(new_block->data, p, ntohs(sl_hdr->len));
- new_block->pipe_fd = pipe_fd;
- new_block->next = last->next;
- last->next = new_block;
- }
- } else {
- int32_t bytes_sent = write(pipe_fd, p, ntohs(sl_hdr->len));
- if(bytes_sent <= 0){
- printf("Error reading to pipe for stream id %d\n",
- sl_hdr->stream_id);
- }
- //increment expected counter
- expected_next_count++;
- }
- //now check to see if there is saved data to write out
- if(saved_data != NULL){
- data_block *current_block = saved_data;
- while((current_block != NULL) &&
- (expected_next_count == current_block->count)){
- int32_t bytes_sent = write(current_block->pipe_fd,
- current_block->data, current_block->len);
- if(bytes_sent <= 0){
- printf("Error reading to pipe for stream id %d\n",
- sl_hdr->stream_id);
- }
- expected_next_count++;
- saved_data = current_block->next;
- free(current_block->data);
- free(current_block);
- current_block = saved_data;
- }
- }
- p += ntohs(sl_hdr->len); //encrypted data
- p += 16; //mac
- p += padding;
- p += ntohs(sl_hdr->garbage);
- bytes_remaining -=
- ntohs(sl_hdr->len) + 16 + padding + 16 + ntohs(sl_hdr->garbage);
- resource_remaining -=
- ntohs(sl_hdr->len) + 16 + padding + 16 + ntohs(sl_hdr->garbage);
- }
- } else {
- printf("Error: read %d bytes from OUS_out\n", bytes_read);
- printf("Re-opening OUS_out... ");
- close(ous_fd);
- ous_fd = open("OUS_out", O_RDONLY);
- printf("done.\n");
- }
-
- }
- free(buffer);
- close(ous_fd);
- }
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