Avoid the PEM issue.

Makefile.in

@@ -73,7 +73,7 @@ install: $(PRPL_LIBNAME)
 	mkdir -m $(DIR_PERM) -p $(DESTDIR)$(PLUGIN_DIR_PURPLE)
 	install -m $(FILE_PERM) $(PRPL_LIBNAME) $(DESTDIR)$(PLUGIN_DIR_PURPLE)/$(PRPL_NAME)
 	mkdir -m $(DIR_PERM) -p $(DESTDIR)/etc/telegram-purple
-	install -m $(FILE_PERM) tg-server.pub $(DESTDIR)/etc/telegram-purple/server.pub
+	install -m $(FILE_PERM) tg-server.tglpub $(DESTDIR)/etc/telegram-purple/server.tglpub
 	mkdir -m $(DIR_PERM) -p $(DESTDIR)$(DATA_ROOT_DIR_PURPLE)/pixmaps/pidgin/protocols/16
 	install -m $(FILE_PERM) imgs/telegram16.png $(DESTDIR)$(DATA_ROOT_DIR_PURPLE)/pixmaps/pidgin/protocols/16/telegram.png
 	mkdir -m $(DIR_PERM) -p $(DESTDIR)$(DATA_ROOT_DIR_PURPLE)/pixmaps/pidgin/protocols/22
@@ -88,7 +88,8 @@ local_install:
 .PHONY: uninstall
 uninstall:
 	rm -f $(DESTDIR)$(PLUGIN_DIR_PURPLE)/$(PRPL_NAME)
-	rm -f $(DESTDIR)/etc/telegram-purple/server.pub
+	rm -f $(DESTDIR)/etc/telegram-purple/server.pub # TODO: Remove this in later versions
+	rm -f $(DESTDIR)/etc/telegram-purple/server.tglpub
 	rm -f $(DESTDIR)$(DATA_ROOT_DIR_PURPLE)/pixmaps/pidgin/protocols/16/telegram.png
 	rm -f $(DESTDIR)$(DATA_ROOT_DIR_PURPLE)/pixmaps/pidgin/protocols/22/telegram.png
 	rm -f $(DESTDIR)$(DATA_ROOT_DIR_PURPLE)/pixmaps/pidgin/protocols/48/telegram.png

README.md

@@ -72,16 +72,19 @@ This repository has submodules, so you need to clone recursively.
 
         sudo dnf install gcc openssl-devel glib2-devel libpurple-devel libwebp-devel
 
+And the development files for gcrypt, probably `gcrypt-devel` or something.
+
 
 ###### Debian / Ubuntu
 
         sudo apt-get install libgcrypt20-dev libssl-dev libpurple-dev libwebp-dev
 
-
 ###### OpenSUSE
 
         sudo zypper install gcc glib glib-devel libpurple libpurple-devel zlib-devel openssl libopenssl-devel libwebp-devel
 
+And the development files for gcrypt, probably `gcrypt-devel` or something.
+
 
 #### 3. Compile and install
 
@@ -188,6 +191,22 @@ Compiling with XCode is a little bit problematic, since it requires you to compi
 Discussion / Help
 -----------------
 
+#### Custom pubkeys
+
+As we want to avoid OpenSSL, it has become necessary to replace the PEM file format. This means that if you use a custom pubkey (which you really REALLY shouldn't be doing), you have to adapt, sorry.
+
+We no longer ship `tg-server.pub` (old format), but instead `tg-server.tlgpub` (new format). If you have a `.pub` and want to continue using telegram-purple, please use this (hopefully highly portable) tool: [pem2bignum](https://github.com/BenWiederhake/pem2bignum)
+
+You can also write your own conversion tool if you prefer. The format is really simple:
+
+1. `e`, the public exponent, encoded as big endian 32 bit fixed length (e.g. `0x00 01 00 01` for 65537)
+2. `n_len`, the length of `n` in bytes, encoded as big endian 32 bit fixed length (e.g. `0x00 00 01 00` for a 2048-bit = 256-byte key)
+3. `n_raw`, the raw modulus, encoded as big endian, using the previously indicated length (e.g. `0xC1 50 02 3E [248 bytes omitted] 21 79 25 1F` in the case of telegram's public RSA key.)
+
+If you are interested in developing a non-OpenSSL-licensed converter, look into [insane-triangle-banana](https://github.com/BenWiederhake/insane-triangle-banana).
+
+#### Group chat
+
 Telegram group chat for telegram-purple or libtgl related discussions or questions:
 
     - https://telegram.me/joinchat/01fb53f301b67d3c7a5532908dfa9a89

telegram-base.c

@@ -51,6 +51,64 @@
 #define STATE_FILE_MAGIC 0x28949a93
 #define SECRET_CHAT_FILE_MAGIC 0x37a1988a
 
+static gboolean read_ui32 (int fd, unsigned int *ret) {
+  typedef char check_int_size[(sizeof (int) >= 4) ? 1 : -1];
+  (void) sizeof (check_int_size);
+
+  unsigned char buf[4];
+  if (4 != read (fd, buf, 4)) {
+    return 0;
+  }
+  /* Ugly but works. */
+  *ret = 0;
+  *ret |= buf[0];
+  *ret <<= 8;
+  *ret |= buf[1];
+  *ret <<= 8;
+  *ret |= buf[2];
+  *ret <<= 8;
+  *ret |= buf[3];
+  return 1;
+}
+
+int read_pubkey_file (const char *name, struct rsa_pubkey *dst) {
+  /* Just to make sure nobody reads garbage. */
+  dst->e = 0;
+  dst->n_len = 0;
+  dst->n_raw = NULL;
+
+  int pubkey_fd = open (name, O_RDONLY);
+  if (pubkey_fd < 0) {
+    return 0;
+  }
+
+  unsigned int e;
+  unsigned int n_len;
+  if (!read_ui32 (pubkey_fd, &e) || !read_ui32 (pubkey_fd, &n_len) // Ensure successful reads
+      || n_len < 128 || n_len > 1024 || e < 5) { // Ensure (at least remotely) sane parameters.
+    close (pubkey_fd);
+    return 0;
+  }
+
+  unsigned char *n_raw = malloc (n_len);
+  if (!n_raw) {
+    close (pubkey_fd);
+    return 0;
+  }
+
+  if (n_len != read (pubkey_fd, n_raw, n_len)) {
+    free (n_raw);
+    close (pubkey_fd);
+    return 0;
+  }
+  close (pubkey_fd);
+
+  dst->e = e;
+  dst->n_len = n_len;
+  dst->n_raw = n_raw;
+  return 1;
+}
+
 void read_state_file (struct tgl_state *TLS) {
   char *name = 0;
   if (asprintf (&name, "%s/%s", TLS->base_path, "state") < 0) {
@@ -406,13 +464,14 @@ gchar *get_download_dir (struct tgl_state *TLS) {
   return dir;
 }
 
-void assert_file_exists (PurpleConnection *gc, const char *filepath, const char *format) {
+gboolean assert_file_exists (PurpleConnection *gc, const char *filepath, const char *format) {
   if (!g_file_test (filepath, G_FILE_TEST_EXISTS)) {
     gchar *msg = g_strdup_printf (format, filepath);
     purple_connection_error_reason (gc, PURPLE_CONNECTION_ERROR_CERT_OTHER_ERROR, msg);
     g_free (msg);
-    return;
+    return 0;
   }
+  return 1;
 }
 
 void export_auth_callback (struct tgl_state *TLS, void *extra, int success) {

telegram-base.h

@@ -22,6 +22,14 @@
 
 #include "telegram-purple.h"
 
+struct rsa_pubkey {
+  unsigned int e;
+  unsigned int n_len;
+  unsigned char *n_raw;
+};
+
+gboolean read_pubkey_file (const char *name, struct rsa_pubkey *dst);
+
 void read_state_file (struct tgl_state *TLS);
 void read_auth_file (struct tgl_state *TLS);
 void write_auth_file (struct tgl_state *TLS);
@@ -37,7 +45,7 @@ void telegram_export_authorization (struct tgl_state *TLS);
 gchar *get_config_dir (struct tgl_state *TLS, char const *username);
 gchar *get_download_dir (struct tgl_state *TLS);
 
-void assert_file_exists (PurpleConnection *gc, const char *filepath, const char *format);
+gboolean assert_file_exists (PurpleConnection *gc, const char *filepath, const char *format);
 
 int tgp_visualize_key (struct tgl_state *TLS, unsigned char* sha1_key);
 void tgp_create_group_chat_by_usernames (struct tgl_state *TLS, const char *title,

telegram-purple.c

@@ -89,7 +89,7 @@ void on_user_get_info (struct tgl_state *TLS, void *info_data, int success, stru
 
 PurpleGroup *tggroup;
 const char *config_dir = "telegram-purple";
-const char *pk_path = "/etc/telegram-purple/server.pub";
+const char *pk_path = "/etc/telegram-purple/server.tglpub";
 
 struct tgl_update_callback tgp_callback = {
   .logprintf = debug,
@@ -575,12 +575,28 @@ static void tgprpl_login (PurpleAccount * acct) {
 
   TLS->base_path = get_config_dir(TLS, purple_account_get_username (acct));
   tgl_set_download_directory (TLS, get_download_dir(TLS));
-  assert_file_exists (gc, pk_path, "Error, server public key not found at %s."
-                      " Make sure that Telegram-Purple is installed properly.");
+  if (!assert_file_exists (gc, pk_path, "Error, server public key not found at %s."
+                      " Make sure that Telegram-Purple is installed properly.")) {
+    /* Already reported. */
+    return;
+  }
+
   debug ("base configuration path: '%s'", TLS->base_path);
   
+  struct rsa_pubkey the_pubkey;
+  if (!read_pubkey_file (pk_path, &the_pubkey)) {
+    char *cause = g_strdup_printf ("Unable to sign on as %s: Missing file %s.",
+                    purple_account_get_username (acct), pk_path);
+    purple_connection_error_reason (gc, PURPLE_CONNECTION_ERROR_INVALID_SETTINGS, cause);
+    purple_notify_message (_telegram_protocol, PURPLE_NOTIFY_MSG_ERROR, cause,
+                            "Make sure telegram-purple is installed properly,\n"
+                            "including the .tglpub file.", NULL, NULL, NULL);
+    g_free (cause);
+    return;
+  }
+
   tgl_set_verbosity (TLS, 4);
-  tgl_set_rsa_key (TLS, pk_path);
+  tgl_set_rsa_key_direct (TLS, the_pubkey.e, the_pubkey.n_len, the_pubkey.n_raw);
   
   tgl_set_ev_base (TLS, conn);
   tgl_set_net_methods (TLS, &tgp_conn_methods);

tg-server.pub

@@ -1,8 +0,0 @@
------BEGIN RSA PUBLIC KEY-----
-MIIBCgKCAQEAwVACPi9w23mF3tBkdZz+zwrzKOaaQdr01vAbU4E1pvkfj4sqDsm6
-lyDONS789sVoD/xCS9Y0hkkC3gtL1tSfTlgCMOOul9lcixlEKzwKENj1Yz/s7daS
-an9tqw3bfUV/nqgbhGX81v/+7RFAEd+RwFnK7a+XYl9sluzHRyVVaTTveB2GazTw
-Efzk2DWgkBluml8OREmvfraX3bkHZJTKX4EQSjBbbdJ2ZXIsRrYOXfaA+xayEGB+
-8hdlLmAjbCVfaigxX0CDqWeR1yFL9kwd9P0NsZRPsmoqVwMbMu7mStFai6aIhc3n
-Slv8kg9qv1m6XHVQY3PnEw+QQtqSIXklHwIDAQAB
------END RSA PUBLIC KEY-----

tgl

@@ -1 +1 @@
-Subproject commit ed4e304be425afecdf954e3d88fae98b80e6ff50
+Subproject commit 391806c60e36f60352abfccf05392f31fa0ba184