Big commit

Makefile

 CC=cc
-CFLAGS=-c -Wall -Wextra -fPIC
-LDFLAGS=-lreadline
+CFLAGS=-c -Wall -Wextra -Werror -fPIC -ggdb -O2 -fno-omit-frame-pointer -fno-strict-aliasing -rdynamic
+LDFLAGS=-lreadline -lssl -lcrypto -lrt -lz -ggdb -rdynamic
 LD=cc
 
-SRC=main.c loop.c interface.c
+SRC=main.c loop.c interface.c net.c mtproto-common.c mtproto-client.c queries.c structures.c
 OBJ=$(SRC:.c=.o)
 EXE=telegram
 

interface.c

@@ -4,10 +4,11 @@
 
 #include <assert.h>
 #include <stdio.h>
-
+#include <stdarg.h>
 #include <stdlib.h>
 #include <string.h>
 #include "include.h"
+#include "queries.h"
 char *default_prompt = ">";
 
 char *get_default_prompt (void) {
@@ -21,11 +22,13 @@ char *complete_none (const char *text UU, int state UU) {
 char *commands[] = {
   "help",
   "msg",
+  "contact_list",
   0 };
 
 int commands_flags[] = {
   070,
   072,
+  00,
 };
 
 char *a = 0;
@@ -151,5 +154,27 @@ char **complete_text (char *text, int start UU, int end UU) {
 }
 
 void interpreter (char *line UU) {
-  assert (0);
+  if (!memcmp (line, "contact_list", 12)) {
+    do_update_contact_list ();
+  }
+}
+
+void rprintf (const char *format, ...) {
+
+  int saved_point = rl_point;
+  char *saved_line = rl_copy_text(0, rl_end);
+  rl_save_prompt();
+  rl_replace_line("", 0);
+  rl_redisplay();
+
+  va_list ap;
+  va_start (ap, format);
+  vfprintf (stdout, format, ap);
+  va_end (ap);
+
+  rl_restore_prompt();
+  rl_replace_line(saved_line, 0);
+  rl_point = saved_point;
+  rl_redisplay();
+  free(saved_line);
 }

interface.h

@@ -4,4 +4,6 @@ char *get_default_prompt (void);
 char *complete_none (const char *text, int state);
 char **complete_text (char *text, int start, int end);
 void interpreter (char *line);
+
+void rprintf (const char *format, ...) __attribute__ ((format (printf, 1, 2)));
 #endif

loop.c

@@ -9,50 +9,178 @@
 #include <readline/history.h>
 
 #include <errno.h>
+#include <poll.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
 
 #include "interface.h"
+#include "net.h"
+#include "mtproto-client.h"
+#include "mtproto-common.h"
+#include "queries.h"
+#include "telegram.h"
+
 extern char *default_username;
 extern char *auth_token;
 void set_default_username (const char *s);
+int default_dc_num;
 
 
+void net_loop (int flags, int (*is_end)(void)) {
+  while (!is_end ()) {
+    struct pollfd fds[101];
+    int cc = 0;
+    if (flags & 1) {
+      fds[0].fd = 0;
+      fds[0].events = POLLIN;
+      cc ++;
+    }
 
-int main_loop (void) {
-  fd_set inp, outp;
-  struct timeval tv;
-  while (1) {
-    FD_ZERO (&inp);
-    FD_ZERO (&outp);
-    FD_SET (0, &inp);
-    tv.tv_sec = 1;
-    tv.tv_usec = 0;
-    
-    int lfd = 0;
-
-    if (select (lfd + 1, &inp, &outp, NULL, &tv) < 0) {
-      if (errno == EINTR) {
+    int x = connections_make_poll_array (fds + cc, 101 - cc) + cc;
+    double timer = next_timer_in ();
+    if (timer > 1000) { timer = 1000; }
+    if (poll (fds, x, timer) < 0) {
       /* resuming from interrupt, so not an error situation,
          this generally happens when you suspend your
          messenger with "C-z" and then "fg". This is allowed "
        */
+      if (flags & 1) {
         rl_reset_line_state ();
         rl_forced_update_display ();
-        continue;
       }
-      perror ("select()");
-      break;
+      work_timers ();
+      continue;
     }
-    
-    if (FD_ISSET (0, &inp)) {
+    work_timers ();
+    if ((flags & 1) && (fds[0].revents & POLLIN)) {
       rl_callback_read_char ();
     }
+    connections_poll_result (fds + cc, x - cc);
   }
+}
+
+int ret1 (void) { return 0; }
+
+int main_loop (void) {
+  net_loop (1, ret1);
   return 0;
 }
 
+
+struct dc *DC_list[MAX_DC_ID + 1];
+struct dc *DC_working;
+int dc_working_num;
+int auth_state;
+char *get_auth_key_filename (void);
+int zero[512];
+
+
+void write_dc (int auth_file_fd, struct dc *DC) {
+  assert (write (auth_file_fd, &DC->port, 4) == 4);
+  int l = strlen (DC->ip);
+  assert (write (auth_file_fd, &l, 4) == 4);
+  assert (write (auth_file_fd, DC->ip, l) == l);
+  if (DC->flags & 1) {
+    assert (write (auth_file_fd, &DC->auth_key_id, 8) == 8);
+    assert (write (auth_file_fd, DC->auth_key, 256) == 256);
+  } else {
+    assert (write (auth_file_fd, zero, 256 + 8) == 256 + 8);
+  }
+ 
+  assert (write (auth_file_fd, &DC->server_salt, 8) == 8);
+}
+
+void write_auth_file (void) {
+  int auth_file_fd = open (get_auth_key_filename (), O_CREAT | O_RDWR, S_IRWXU);
+  assert (auth_file_fd >= 0);
+  int x = DC_SERIALIZED_MAGIC;
+  assert (write (auth_file_fd, &x, 4) == 4);
+  x = MAX_DC_ID;
+  assert (write (auth_file_fd, &x, 4) == 4);
+  assert (write (auth_file_fd, &dc_working_num, 4) == 4);
+  assert (write (auth_file_fd, &auth_state, 4) == 4);
+  int i;
+  for (i = 0; i <= MAX_DC_ID; i++) {
+    if (DC_list[i]) {
+      x = 1;
+      assert (write (auth_file_fd, &x, 4) == 4);
+      write_dc (auth_file_fd, DC_list[i]);
+    } else {
+      x = 0;
+      assert (write (auth_file_fd, &x, 4) == 4);
+    }
+  }
+  close (auth_file_fd);
+}
+
+void read_dc (int auth_file_fd, int id) {
+  int port = 0;
+  assert (read (auth_file_fd, &port, 4) == 4);
+  int l = 0;
+  assert (read (auth_file_fd, &l, 4) == 4);
+  assert (l >= 0);
+  char *ip = malloc (l + 1);
+  assert (read (auth_file_fd, ip, l) == l);
+  ip[l] = 0;
+  struct dc *DC = alloc_dc (id, ip, port);
+  assert (read (auth_file_fd, &DC->auth_key_id, 8) == 8);
+  assert (read (auth_file_fd, &DC->auth_key, 256) == 256);
+  assert (read (auth_file_fd, &DC->server_salt, 8) == 8);
+  if (DC->auth_key_id) {
+    DC->flags |= 1;
+  }
+}
+
+void empty_auth_file (void) {
+  struct dc *DC = alloc_dc (1, strdup (TG_SERVER), 443);
+  assert (DC);
+  dc_working_num = 1;
+  write_auth_file ();
+}
+
+void read_auth_file (void) {
+  int auth_file_fd = open (get_auth_key_filename (), O_CREAT | O_RDWR, S_IRWXU);
+  if (auth_file_fd < 0) {
+    empty_auth_file ();
+  }
+  assert (auth_file_fd >= 0);
+  int x;
+  if (read (auth_file_fd, &x, 4) < 4 || x != DC_SERIALIZED_MAGIC) {
+    close (auth_file_fd);
+    empty_auth_file ();
+    return;
+  }
+  assert (read (auth_file_fd, &x, 4) == 4);
+  assert (x >= 0 && x <= MAX_DC_ID);
+  assert (read (auth_file_fd, &dc_working_num, 4) == 4);
+  assert (read (auth_file_fd, &auth_state, 4) == 4);
+  int i;
+  for (i = 0; i <= x; i++) {
+    int y;
+    assert (read (auth_file_fd, &y, 4) == 4);
+    if (y) {
+      read_dc (auth_file_fd, i);
+    }
+  }
+  close (auth_file_fd);
+}
+
 int loop (void) {
+  on_start ();
+  read_auth_file ();
+  assert (DC_list[dc_working_num]);
+  DC_working = DC_list[dc_working_num];
+  if (!DC_working->auth_key_id) {
+    dc_authorize (DC_working);
+  } else {
+    dc_create_session (DC_working);
+  }
+  if (!auth_state) {
+    if (!default_username) {
       size_t size = 0;
-  char *user = default_username;
+      char *user = 0;
 
       if (!user && !auth_token) {
         printf ("Telephone number (with '+' sign): ");         
@@ -60,11 +188,33 @@ int loop (void) {
           perror ("getline()");
           exit (EXIT_FAILURE);
         }
-    user[strlen (user) - 1] = '\0';      
+        user[strlen (user) - 1] = 0;      
         set_default_username (user);
       }
+    }
+    do_send_code (default_username);
+    char *code = 0;
+    size_t size = 0;
+    printf ("Code from sms: ");
+    while (1) {
+      if (getline (&code, &size, stdin) == -1) {
+        perror ("getline()");
+        exit (EXIT_FAILURE);
+      }
+      code[strlen (code) - 1] = 0;      
+      if (do_send_code_result (code) >= 0) {
+        break;
+      }
+      printf ("Invalid code. Try again: ");
+    }
+    auth_state = 1;
+  }
+
+  write_auth_file ();
   
   fflush (stdin);
+  fflush (stdout);
+  fflush (stderr);
 
   rl_callback_handler_install (get_default_prompt (), interpreter);
   rl_attempted_completion_function = (CPPFunction *) complete_text;

loop.h

 #ifndef __LOOP_H__
 #define __LOOP_H__
 int loop (void);
+void net_loop (int flags, int (*end)(void));
+void write_auth_file (void);
 #endif

main.c

@@ -27,14 +27,18 @@
 #include <sys/stat.h>
 #include <time.h>
 #include <fcntl.h>
+#include <execinfo.h>
+#include <signal.h>
 
 #include "loop.h"
+#include "mtproto-client.h"
 
 #define PROGNAME "telegram-client"
 #define VERSION "0.01"
 
 #define CONFIG_DIRECTORY ".telegram/"
 #define CONFIG_FILE CONFIG_DIRECTORY "config"
+#define AUTH_KEY_FILE CONFIG_DIRECTORY "auth"
 #define DOWNLOADS_DIRECTORY "downloads/"
 
 #define CONFIG_DIRECTORY_MODE 0700
@@ -72,6 +76,13 @@ void get_terminal_attributes (void) {
   old_lflag = term.c_lflag;
   old_vtime = term.c_cc[VTIME];
 }
+
+void set_terminal_attributes (void) {
+  if (tcsetattr (STDIN_FILENO, 0, &term) < 0) {
+    perror ("tcsetattr()");
+    exit (EXIT_FAILURE);
+  }
+}
 /* }}} */
 
 char *get_home_directory (void) {
@@ -107,6 +118,15 @@ char *get_config_filename (void) {
   return config_filename;
 }
 
+char *get_auth_key_filename (void) {
+  char *auth_key_filename;
+  int length = strlen (get_home_directory ()) + strlen (AUTH_KEY_FILE) + 2;
+
+  auth_key_filename = (char *) calloc (length, sizeof (char));
+  sprintf (auth_key_filename, "%s/" AUTH_KEY_FILE, get_home_directory ());
+  return auth_key_filename;
+}
+
 char *get_downloads_directory (void)
 {
   char *downloads_directory;
@@ -149,6 +169,11 @@ void running_for_first_time (void) {
       exit (EXIT_FAILURE);
     }
     close (config_file_fd);
+    int auth_file_fd = open (get_auth_key_filename (), O_CREAT | O_RDWR, S_IRWXU);
+    int x = -1;
+    assert (write (auth_file_fd, &x, 4) == 4);
+    close (auth_file_fd);
+
     printf ("[%s] created\n", config_filename);
   
     /* create downloads directory */
@@ -170,13 +195,26 @@ void usage (void) {
   exit (1);
 }
 
+extern char *rsa_public_key_name;
+extern int verbosity;
+extern int default_dc_num;
+
 void args_parse (int argc, char **argv) {
   int opt = 0;
-  while ((opt = getopt (argc, argv, "u:h")) != -1) {
+  while ((opt = getopt (argc, argv, "u:hk:vn:")) != -1) {
     switch (opt) {
     case 'u':
       set_default_username (optarg);
       break;
+    case 'k':
+      rsa_public_key_name = strdup (optarg);
+      break;
+    case 'v':
+      verbosity ++;
+      break;
+    case 'n':
+      default_dc_num = atoi (optarg);
+      break;
     case 'h':
     default:
       usage ();
@@ -185,7 +223,23 @@ void args_parse (int argc, char **argv) {
   }
 }
 
+void print_backtrace (void) {
+  void *buffer[255];
+  const int calls = backtrace (buffer, sizeof (buffer) / sizeof (void *));
+  backtrace_symbols_fd (buffer, calls, 1);
+  exit(EXIT_FAILURE);
+}
+
+void sig_handler (int signum) {
+  set_terminal_attributes ();
+  printf ("signal %d received\n", signum);
+  print_backtrace ();
+}
+
+
 int main (int argc, char **argv) {
+  signal (SIGSEGV, sig_handler);
+  signal (SIGABRT, sig_handler);
   running_for_first_time ();
 
   get_terminal_attributes ();

mtproto-client.h

+#ifndef __MTPROTO_CLIENT_H__
+#define __MTPROTO_CLIENT_H__
+#include "net.h"
+void on_start (void);
+long long encrypt_send_message (struct connection *c, int *msg, int msg_ints, int useful);
+void dc_authorize (struct dc *DC);
+#endif

mtproto-common.c

+#define	_FILE_OFFSET_BITS	64
+
+#include <assert.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <aio.h>
+#include <netdb.h>
+#include <openssl/bn.h>
+#include <openssl/rand.h>
+#include <openssl/pem.h>
+#include <openssl/aes.h>
+#include <openssl/sha.h>
+
+#include "mtproto-common.h"
+
+long long rsa_encrypted_chunks, rsa_decrypted_chunks;
+
+BN_CTX *BN_ctx;
+int verbosity;
+
+int get_random_bytes (void *buf, int n) {
+  int r = 0, h = open ("/dev/random", O_RDONLY | O_NONBLOCK);
+  if (h >= 0) {
+    r = read (h, buf, n);
+    if (r > 0) {
+      if (verbosity >= 3) {
+        fprintf (stderr, "added %d bytes of real entropy to secure random numbers seed\n", r);
+      }
+    }
+    close (h);
+  }
+
+  if (r < n) {
+    h = open ("/dev/urandom", O_RDONLY);
+    if (h < 0) {
+      return r;
+    }
+    int s = read (h, buf + r, n - r);
+    close (h);
+    if (s < 0) {
+      return r;
+    }
+    r += s;
+  }
+
+  if (r >= (int)sizeof (long)) {
+    *(long *)buf ^= lrand48 ();
+    srand48 (*(long *)buf);
+  }
+
+  return r;
+}
+
+
+void prng_seed (const char *password_filename, int password_length) {
+  unsigned char *a = calloc (64 + password_length, 1);
+  assert (a != NULL);
+  long long r = rdtsc ();
+  struct timespec T;
+  assert (clock_gettime(CLOCK_REALTIME, &T) >= 0);
+  memcpy (a, &T.tv_sec, 4);
+  memcpy (a+4, &T.tv_nsec, 4);
+  memcpy (a+8, &r, 8);
+  unsigned short p = getpid ();
+  memcpy (a + 16, &p, 2);
+  int s = get_random_bytes (a + 18, 32) + 18;
+  if (password_filename) {
+    int fd = open (password_filename, O_RDONLY);
+    if (fd < 0) {
+      fprintf (stderr, "Warning: fail to open password file - \"%s\", %m.\n", password_filename);
+    } else {
+      int l = read (fd, a + s, password_length);
+      if (l < 0) {
+        fprintf (stderr, "Warning: fail to read password file - \"%s\", %m.\n", password_filename);
+      } else {
+        if (verbosity > 0) {
+          fprintf (stderr, "read %d bytes from password file.\n", l);
+        }
+        s += l;
+      }
+      close (fd);
+    }
+  }
+  RAND_seed (a, s);
+  BN_ctx = BN_CTX_new ();
+  memset (a, 0, s);
+  free (a);
+}
+
+int serialize_bignum (BIGNUM *b, char *buffer, int maxlen) {
+  int itslen = BN_num_bytes (b);
+  int reqlen;
+  if (itslen < 254) {
+    reqlen = itslen + 1;
+  } else {
+    reqlen = itslen + 4;
+  }
+  int newlen = (reqlen + 3) & -4;
+  int pad = newlen - reqlen;
+  reqlen = newlen;
+  if (reqlen > maxlen) {
+    return -reqlen;
+  }
+  if (itslen < 254) {
+    *buffer++ = itslen;
+  } else {
+    *(int *)buffer = (itslen << 8) + 0xfe;
+    buffer += 4;
+  }
+  int l = BN_bn2bin (b, (unsigned char *)buffer);
+  assert (l == itslen);
+  buffer += l;
+  while (pad --> 0) {
+    *buffer++ = 0;
+  }
+  return reqlen;
+}
+
+
+long long compute_rsa_key_fingerprint (RSA *key) {
+  static char tempbuff[4096];
+  static unsigned char sha[20]; 
+  assert (key->n && key->e);
+  int l1 = serialize_bignum (key->n, tempbuff, 4096);
+  assert (l1 > 0);
+  int l2 = serialize_bignum (key->e, tempbuff + l1, 4096 - l1);
+  assert (l2 > 0 && l1 + l2 <= 4096);
+  SHA1 ((unsigned char *)tempbuff, l1 + l2, sha);
+  return *(long long *)(sha + 12);
+}
+
+void out_cstring (const char *str, long len) {
+  assert (len >= 0 && len < (1 << 24));
+  assert ((char *) packet_ptr + len + 8 < (char *) (packet_buffer + PACKET_BUFFER_SIZE));
+  char *dest = (char *) packet_ptr;
+  if (len < 254) {
+    *dest++ = len;
+  } else {
+    *packet_ptr = (len << 8) + 0xfe;
+    dest += 4;
+  }
+  memcpy (dest, str, len);
+  dest += len;
+  while ((long) dest & 3) {
+    *dest++ = 0;
+  }
+  packet_ptr = (int *) dest;
+}
+
+void out_cstring_careful (const char *str, long len) {
+  assert (len >= 0 && len < (1 << 24));
+  assert ((char *) packet_ptr + len + 8 < (char *) (packet_buffer + PACKET_BUFFER_SIZE));
+  char *dest = (char *) packet_ptr;
+  if (len < 254) {
+    dest++;
+    if (dest != str) {
+      memmove (dest, str, len);
+    }
+    dest[-1] = len;
+  } else {
+    dest += 4;
+    if (dest != str) {
+      memmove (dest, str, len);
+    }
+    *packet_ptr = (len << 8) + 0xfe;
+  }
+  dest += len;
+  while ((long) dest & 3) {
+    *dest++ = 0;
+  }
+  packet_ptr = (int *) dest;
+}
+
+
+void out_data (const char *data, long len) {
+  assert (len >= 0 && len < (1 << 24) && !(len & 3));
+  assert ((char *) packet_ptr + len + 8 < (char *) (packet_buffer + PACKET_BUFFER_SIZE));
+  memcpy (packet_ptr, data, len);
+  packet_ptr += len >> 2;
+}
+
+int *in_ptr, *in_end;
+
+int fetch_bignum (BIGNUM *x) {
+  int l = prefetch_strlen ();
+  if (l < 0) {
+    return l;
+  }
+  char *str = fetch_str (l);
+  assert (BN_bin2bn ((unsigned char *) str, l, x) == x);
+  return l;
+}
+
+int pad_rsa_encrypt (char *from, int from_len, char *to, int size, BIGNUM *N, BIGNUM *E) {
+  int pad = (255000 - from_len - 32) % 255 + 32;
+  int chunks = (from_len + pad) / 255;
+  int bits = BN_num_bits (N);
+  assert (bits >= 2041 && bits <= 2048);
+  assert (from_len > 0 && from_len <= 2550);
+  assert (size >= chunks * 256);
+  assert (RAND_pseudo_bytes ((unsigned char *) from + from_len, pad) >= 0);
+  int i;
+  BIGNUM x, y;
+  BN_init (&x);
+  BN_init (&y);
+  rsa_encrypted_chunks += chunks;
+  for (i = 0; i < chunks; i++) {
+    BN_bin2bn ((unsigned char *) from, 255, &x);
+    assert (BN_mod_exp (&y, &x, E, N, BN_ctx) == 1);
+    unsigned l = 256 - BN_num_bytes (&y);
+    assert (l <= 256);
+    memset (to, 0, l);
+    BN_bn2bin (&y, (unsigned char *) to + l);
+    to += 256;
+  }
+  BN_free (&x);
+  BN_free (&y);
+  return chunks * 256;
+}
+
+int pad_rsa_decrypt (char *from, int from_len, char *to, int size, BIGNUM *N, BIGNUM *D) {
+  if (from_len < 0 || from_len > 0x1000 || (from_len & 0xff)) {
+    return -1;
+  }
+  int chunks = (from_len >> 8);
+  int bits = BN_num_bits (N);
+  assert (bits >= 2041 && bits <= 2048);
+  assert (size >= chunks * 255);
+  int i;
+  BIGNUM x, y;
+  BN_init (&x);
+  BN_init (&y);
+  for (i = 0; i < chunks; i++) {
+    ++rsa_decrypted_chunks;
+    BN_bin2bn ((unsigned char *) from, 256, &x);
+    assert (BN_mod_exp (&y, &x, D, N, BN_ctx) == 1);
+    int l = BN_num_bytes (&y);
+    if (l > 255) {
+      BN_free (&x);
+      BN_free (&y);
+      return -1;
+    }
+    assert (l >= 0 && l <= 255);
+    memset (to, 0, 255 - l);
+    BN_bn2bin (&y, (unsigned char *) to + 255 - l);
+    to += 255;
+  }
+  BN_free (&x);
+  BN_free (&y);
+  return chunks * 255;
+}
+
+unsigned char aes_key_raw[32], aes_iv[32];
+AES_KEY aes_key;
+
+void init_aes_unauth (const char server_nonce[16], const char hidden_client_nonce[32], int encrypt) {
+  static unsigned char buffer[64], hash[20];
+  memcpy (buffer, hidden_client_nonce, 32);
+  memcpy (buffer + 32, server_nonce, 16);
+  SHA1 (buffer, 48, aes_key_raw);
+  memcpy (buffer + 32, hidden_client_nonce, 32);
+  SHA1 (buffer, 64, aes_iv + 8);
+  memcpy (buffer, server_nonce, 16);
+  memcpy (buffer + 16, hidden_client_nonce, 32);
+  SHA1 (buffer, 48, hash);
+  memcpy (aes_key_raw + 20, hash, 12);
+  memcpy (aes_iv, hash + 12, 8);
+  memcpy (aes_iv + 28, hidden_client_nonce, 4);
+  if (encrypt == AES_ENCRYPT) {
+    AES_set_encrypt_key (aes_key_raw, 32*8, &aes_key);
+  } else {
+    AES_set_decrypt_key (aes_key_raw, 32*8, &aes_key);
+  }
+}
+
+void init_aes_auth (char auth_key[192], char msg_key[16], int encrypt) {
+  static unsigned char buffer[48], hash[20];
+  //  sha1_a = SHA1 (msg_key + substr (auth_key, 0, 32));
+  //  sha1_b = SHA1 (substr (auth_key, 32, 16) + msg_key + substr (auth_key, 48, 16));
+  //  sha1_с = SHA1 (substr (auth_key, 64, 32) + msg_key);
+  //  sha1_d = SHA1 (msg_key + substr (auth_key, 96, 32));
+  //  aes_key = substr (sha1_a, 0, 8) + substr (sha1_b, 8, 12) + substr (sha1_c, 4, 12);
+  //  aes_iv = substr (sha1_a, 8, 12) + substr (sha1_b, 0, 8) + substr (sha1_c, 16, 4) + substr (sha1_d, 0, 8);
+  memcpy (buffer, msg_key, 16);
+  memcpy (buffer + 16, auth_key, 32);
+  SHA1 (buffer, 48, hash);
+  memcpy (aes_key_raw, hash, 8);
+  memcpy (aes_iv, hash + 8, 12);
+
+  memcpy (buffer, auth_key + 32, 16);
+  memcpy (buffer + 16, msg_key, 16);
+  memcpy (buffer + 32, auth_key + 48, 16);
+  SHA1 (buffer, 48, hash);
+  memcpy (aes_key_raw + 8, hash + 8, 12);
+  memcpy (aes_iv + 12, hash, 8);
+
+  memcpy (buffer, auth_key + 64, 32);
+  memcpy (buffer + 32, msg_key, 16);
+  SHA1 (buffer, 48, hash);
+  memcpy (aes_key_raw + 20, hash + 4, 12);
+  memcpy (aes_iv + 20, hash + 16, 4);
+
+  memcpy (buffer, msg_key, 16);
+  memcpy (buffer + 16, auth_key + 96, 32);
+  SHA1 (buffer, 48, hash);
+  memcpy (aes_iv + 24, hash, 8);
+  
+  if (encrypt == AES_ENCRYPT) {
+    AES_set_encrypt_key (aes_key_raw, 32*8, &aes_key);
+  } else {
+    AES_set_decrypt_key (aes_key_raw, 32*8, &aes_key);
+  }
+}
+
+int pad_aes_encrypt (char *from, int from_len, char *to, int size) {
+  int padded_size = (from_len + 15) & -16;
+  assert (from_len > 0 && padded_size <= size);
+  if (from_len < padded_size) {
+    assert (RAND_pseudo_bytes ((unsigned char *) from + from_len, padded_size - from_len) >= 0);
+  }
+  AES_ige_encrypt ((unsigned char *) from, (unsigned char *) to, padded_size, &aes_key, aes_iv, AES_ENCRYPT);
+  return padded_size;
+}
+
+int pad_aes_decrypt (char *from, int from_len, char *to, int size) {
+  if (from_len <= 0 || from_len > size || (from_len & 15)) {
+    return -1;
+  }
+  AES_ige_encrypt ((unsigned char *) from, (unsigned char *) to, from_len, &aes_key, aes_iv, AES_DECRYPT); 
+  return from_len;
+}
+
+

net.h

+#ifndef __NET_H__
+#define __NET_H__
+
+#include <poll.h>
+struct dc;
+#include "queries.h"
+#define TG_SERVER "173.240.5.1"
+//#define TG_SERVER "95.142.192.66"
+#define TG_APP_HASH "3bc14c6455ef1595ec86a125762c3aad"
+#define TG_APP_ID 51
+
+#define ACK_TIMEOUT 60
+#define MAX_DC_ID 10
+
+enum dc_state{
+  st_init,
+  st_reqpq_sent,
+  st_reqdh_sent,
+  st_client_dh_sent,
+  st_authorized,
+  st_error
+} ;
+
+struct connection;
+struct connection_methods {
+  int (*ready) (struct connection *c);
+  int (*close) (struct connection *c);
+  int (*execute) (struct connection *c, int op, int len);
+};
+
+
+#define MAX_DC_SESSIONS 3
+
+struct session {
+  struct dc *dc;
+  long long session_id;
+  int seq_no;
+  struct connection *c;
+  struct tree_int *ack_tree;
+  struct event_timer ev;
+};
+
+struct dc {
+  int id;
+  int port;
+  int flags;
+  char *ip;
+  char *user;
+  struct session *sessions[MAX_DC_SESSIONS];
+  char auth_key[256];
+  long long auth_key_id;
+  long long server_salt;
+
+  int server_time_delta;
+  double server_time_udelta;
+};
+
+#define DC_SERIALIZED_MAGIC 0x64582faa
+struct dc_serialized {
+  int magic;
+  int port;
+  char ip[64];
+  char user[64];
+  char auth_key[256];
+  long long auth_key_id, server_salt;
+  int authorized;
+};
+
+struct connection_buffer {
+  void *start;
+  void *end;
+  void *rptr;
+  void *wptr;
+  struct connection_buffer *next;
+};
+
+enum conn_state {
+  conn_none,
+  conn_connecting,
+  conn_ready,
+  conn_failed,
+  conn_stopped
+};
+
+struct connection {
+  int fd;
+  int ip;
+  int port;
+  int flags;
+  enum conn_state state;
+  int ipv6[4];
+  struct connection_buffer *in_head;
+  struct connection_buffer *in_tail;
+  struct connection_buffer *out_head;
+  struct connection_buffer *out_tail;
+  int in_bytes;
+  int out_bytes;
+  int packet_num;
+  int out_packet_num;
+  struct connection_methods *methods;
+  struct session *session;
+  void *extra;
+};
+
+extern struct connection *Connections[];
+
+int write_out (struct connection *c, const void *data, int len);
+void flush_out (struct connection *c);
+int read_in (struct connection *c, void *data, int len);
+
+void create_all_outbound_connections (void);
+
+struct connection *create_connection (const char *host, int port, struct session *session, struct connection_methods *methods);
+int connections_make_poll_array (struct pollfd *fds, int max);
+void connections_poll_result (struct pollfd *fds, int max);
+void dc_create_session (struct dc *DC);
+void insert_seqno (struct session *S, int seqno);
+struct dc *alloc_dc (int id, char *ip, int port);
+
+#define GET_DC(c) (c->session->dc)
+#endif

queries.h

+#include "net.h"
+#ifndef __QUERIES_H__
+#define __QUERIES_H__
+
+#define QUERY_ACK_RECEIVED 1
+
+struct query;
+struct query_methods {
+  int (*on_answer)(struct query *q);
+  int (*on_error)(struct query *q, int error_code, int len, char *error);
+  int (*on_timeout)(struct query *q);
+};
+
+struct event_timer {
+  double timeout;
+  int (*alarm)(void *self);
+  void *self;
+};
+
+struct query {
+  long long msg_id;
+  int data_len;
+  int flags;
+  void *data;
+  struct query_methods *methods;
+  struct event_timer ev;
+};
+
+
+struct query *send_query (struct dc *DC, int len, void *data, struct query_methods *methods);
+void query_ack (long long id);
+void query_error (long long id);
+void query_result (long long id);
+
+void insert_event_timer (struct event_timer *ev);
+void remove_event_timer (struct event_timer *ev);
+double next_timer_in (void);
+void work_timers (void);
+
+extern struct query_methods help_get_config_methods;
+
+void do_send_code (const char *user);
+int do_send_code_result (const char *code);
+double get_double_time (void);
+
+void do_update_contact_list (void);
+#endif

structures.c

+#include <assert.h>
+#include "structures.h"
+#include "mtproto-common.h"
+
+void fetch_file_location (struct file_location *loc) {
+  int x = fetch_int ();
+  if (x == CODE_file_location_unavailable) {
+    loc->dc = -1;
+    loc->volume = fetch_long ();
+    loc->local_id = fetch_int ();
+    loc->secret = fetch_long ();
+  } else {
+    assert (x == CODE_file_location);
+    loc->dc = fetch_int ();;
+    loc->volume = fetch_long ();
+    loc->local_id = fetch_int ();
+    loc->secret = fetch_long ();
+  }
+}
+
+void fetch_user_status (struct user_status *S) {
+  int x = fetch_int ();
+  switch (x) {
+  case CODE_user_status_empty:
+    S->online = 0;
+    break;
+  case CODE_user_status_online:
+    S->online = 1;
+    S->when = fetch_int ();
+    break;
+  case CODE_user_status_offline:
+    S->online = -1;
+    S->when = fetch_int ();
+    break;
+  default:
+    assert (0);
+  }
+}
+
+void fetch_user (struct user *U) {
+  memset (U, 0, sizeof (*U));
+  unsigned x = fetch_int ();
+  assert (x == CODE_user_empty || x == CODE_user_self || x == CODE_user_contact ||  x == CODE_user_request || x == CODE_user_foreign || x == CODE_user_deleted);
+  U->id = fetch_int ();
+  if (x == CODE_user_empty) {
+    U->flags = 1;
+    return;
+  }
+  U->first_name = fetch_str_dup ();
+  U->last_name = fetch_str_dup ();
+  if (x == CODE_user_deleted) {
+    U->flags = 2;
+    return;
+  }
+  if (x == CODE_user_self) {
+    U->flags = 4;
+  } else {
+    U->access_hash = fetch_long ();
+  }
+  if (x == CODE_user_foreign) {
+    U->flags |= 8;
+  } else {
+    U->phone = fetch_str_dup ();
+  }
+  unsigned y = fetch_int ();
+  if (y == CODE_user_profile_photo_empty) {
+    U->photo_small.dc = -2;
+    U->photo_big.dc = -2;
+  } else {
+    assert (y == CODE_user_profile_photo);
+    fetch_file_location (&U->photo_small);
+    fetch_file_location (&U->photo_big);
+  }
+  fetch_user_status (&U->status);
+  if (x == CODE_user_self) {
+    assert (fetch_int () == (int)CODE_bool_false);
+  }
+  if (x == CODE_user_contact) {
+    U->flags |= 16;
+  }
+}

structures.h

+#ifndef __STRUCTURES_H__
+#define __STRUCTURES_H__
+
+
+struct file_location {
+  int dc;
+  long long volume;
+  int local_id;
+  long long secret;
+};
+
+struct user_status {
+  int online;
+  int when;
+};
+
+struct user {
+  int id;
+  int flags;
+  char *first_name;
+  char *last_name;
+  char *phone;
+  long long access_hash;
+  struct file_location photo_big;
+  struct file_location photo_small;
+  struct user_status status;
+};
+
+void fetch_file_location (struct file_location *loc);
+void fetch_user (struct user *U);
+#endif

telegram.h

+#define MAX_DC_NUM 9

tree.h

+#ifndef __TREE_H__
+#define __TREE_H__
+#include <stdio.h>
+
+#include <memory.h>
+#include <malloc.h>
+#include <assert.h>
+
+#define DEFINE_TREE(X_NAME, X_TYPE, X_CMP, X_UNSET) \
+struct tree_ ## X_NAME { \
+  struct tree_ ## X_NAME *left, *right;\
+  X_TYPE x;\
+  int y;\
+};\
+\
+struct tree_ ## X_NAME *new_tree_node_ ## X_NAME (X_TYPE x, int y) {\
+  struct tree_ ## X_NAME *T = malloc (sizeof (*T));\
+  T->x = x;\
+  T->y = y;\
+  T->left = T->right = 0;\
+  return T;\
+}\
+\
+void delete_tree_node_ ## X_NAME (struct tree_ ## X_NAME *T) {\
+  free (T);\
+}\
+\
+void tree_split_ ## X_NAME (struct tree_ ## X_NAME *T, X_TYPE x, struct tree_ ## X_NAME **L, struct tree_ ## X_NAME **R) {\
+  if (!T) {\
+    *L = *R = 0;\
+  } else {\
+    int c = X_CMP (x, T->x);\
+    if (c < 0) {\
+      tree_split_ ## X_NAME (T->left, x, L, &T->left);\
+      *R = T;\
+    } else {\
+      tree_split_ ## X_NAME (T->right, x, &T->right, R);\
+      *L = T;\
+    }\
+  }\
+}\
+\
+struct tree_ ## X_NAME *tree_insert_ ## X_NAME (struct tree_ ## X_NAME *T, X_TYPE x, int y) {\
+  if (!T) {\
+    return new_tree_node_ ## X_NAME  (x, y);\
+  } else {\
+    if (y > T->y) {\
+      struct tree_ ## X_NAME *N = new_tree_node_ ## X_NAME (x, y);\
+      tree_split_ ## X_NAME (T, x, &N->left, &N->right);\
+      return N;\
+    } else {\
+      int c = X_CMP (x, T->x);\
+      assert (c);\
+      return tree_insert_ ## X_NAME (c < 0 ? T->left : T->right, x, y);\
+    }\
+  }\
+}\
+\
+struct tree_ ## X_NAME *tree_merge_ ## X_NAME (struct tree_ ## X_NAME *L, struct tree_ ## X_NAME *R) {\
+  if (!L || !R) {\
+    return L ? L : R;\
+  } else {\
+    if (L->y > R->y) {\
+      L->right = tree_merge_ ## X_NAME (L->right, R);\
+      return L;\
+    } else {\
+      R->left = tree_merge_ ## X_NAME (L, R->left);\
+      return R;\
+    }\
+  }\
+}\
+\
+struct tree_ ## X_NAME *tree_delete_ ## X_NAME (struct tree_ ## X_NAME *T, X_TYPE x) {\
+  assert (T);\
+  int c = X_CMP (x, T->x);\
+  if (!c) {\
+    struct tree_ ## X_NAME *N = tree_merge_ ## X_NAME (T->left, T->right);\
+    delete_tree_node_ ## X_NAME (T);\
+    return N;\
+  } else {\
+    return tree_delete_ ## X_NAME (c < 0 ? T->left : T->right, x);\
+  }\
+}\
+\
+X_TYPE tree_get_min_ ## X_NAME (struct tree_ ## X_NAME *T) {\
+  if (!T) { return X_UNSET; } \
+  while (T->left) { T = T->left; }\
+  return T->x; \
+} \
+\
+X_TYPE tree_lookup_ ## X_NAME (struct tree_ ## X_NAME *T, X_TYPE x) {\
+  int c;\
+  while (T && (c = X_CMP (x, T->x))) {\
+    T = (c < 0 ? T->left : T->right);\
+  }\
+  return T ? T->x : X_UNSET;\
+}\
+\
+int tree_count_ ## X_NAME (struct tree_ ## X_NAME *T) { \
+  if (!T) { return 0; }\
+  return 1 + tree_count_ ## X_NAME (T->left) + tree_count_ ## X_NAME (T->right); \
+}\
+void tree_check_ ## X_NAME (struct tree_ ## X_NAME *T) { \
+  if (!T) { return; }\
+  if (T->left) { \
+    assert (T->left->y <= T->y);\
+    assert (X_CMP (T->left->x, T->x) < 0); \
+  }\
+  if (T->right) { \
+    assert (T->right->y <= T->y);\
+    assert (X_CMP (T->right->x, T->x) > 0); \
+  }\
+}\
+
+#define int_cmp(a,b) ((a) - (b))
+#endif