Properly initialize libgcrypt on start

4 files changed, 59 insertions, 1 deletions

diff --git a/crypto/err.h b/crypto/err.h
index ec6c6f6..efee156 100644
--- a/crypto/err.h
+++ b/crypto/err.h
@@ -25,4 +25,10 @@
 
 void TGLC_err_print_errors_fp (FILE *fp);
 
+// Don't want to include tgl.h just for this
+struct tgl_state;
+
+// Init crypto backend, log to TLS
+int TGLC_init (struct tgl_state *TLS);
+
 #endif
diff --git a/crypto/err_altern.c b/crypto/err_altern.c
index 219b161..610e205 100644
--- a/crypto/err_altern.c
+++ b/crypto/err_altern.c
@@ -24,6 +24,8 @@
 
 #include <gcrypt.h>
 
+#include "../tgl.h"
+#include "../tgl-inner.h"
 #include "err.h"
 
 void TGLC_err_print_errors_fp (FILE *fp) {
@@ -31,4 +33,43 @@ void TGLC_err_print_errors_fp (FILE *fp) {
   (void) fp;
 }
 
+int TGLC_init (struct tgl_state *TLS) {
+  vlogprintf (E_NOTICE, "Init gcrypt\n");
+  // https://gnupg.org/documentation/manuals/gcrypt/Initializing-the-library.html
+  // https://lists.gnupg.org/pipermail/gcrypt-devel/2003-August/000458.html
+
+  if (gcry_control (GCRYCTL_INITIALIZATION_FINISHED_P)) {
+    // Someone else already *completed* it.
+    vlogprintf (E_NOTICE, "Init gcrypt: already initialized -- good\n");
+    return 0;
+  }
+
+  if (gcry_control (GCRYCTL_ANY_INITIALIZATION_P)) {
+    // Someone else already *started* it without *completing*.
+    vlogprintf (E_WARNING, "Init gcrypt: already started *but not completed* by third party -- bad\n");
+    vlogprintf (E_WARNING, "Init gcrypt: ... not trying to init gcrypt then.\n");
+    return 0;
+  }
+
+  if (!gcry_check_version (GCRYPT_VERSION)) {
+    vlogprintf (E_ERROR, "Init gcrypt: version mismatch!\n");
+    return -1;
+  }
+
+  gcry_error_t err = gcry_control (GCRYCTL_DISABLE_SECMEM, NULL, 0);
+  if (err != GPG_ERR_NO_ERROR) {
+    vlogprintf (E_ERROR, "Init gcrypt: secmem failed?!\n");
+    return -1;
+  }
+
+  /* Tell Libgcrypt that initialization has completed. */
+  err = gcry_control (GCRYCTL_INITIALIZATION_FINISHED, 0);
+  if (err != GPG_ERR_NO_ERROR) {
+    vlogprintf (E_ERROR, "Init gcrypt: init failed?!\n");
+    return -1;
+  }
+
+  return 0;
+}
+
 #endif
diff --git a/crypto/err_openssl.c b/crypto/err_openssl.c
index b9dab5c..74b61df 100644
--- a/crypto/err_openssl.c
+++ b/crypto/err_openssl.c
@@ -30,4 +30,10 @@ void TGLC_err_print_errors_fp (FILE *fp) {
   ERR_print_errors_fp (fp);
 }
 
+int TGLC_init (void) {
+  // Doesn't seem to need any initialization.
+  vlogprintf (E_DEBUG, "Init OpenSSL (no-op)\n");
+  return !0;
+}
+
 #endif
diff --git a/tgl.c b/tgl.c
index 5234747..187f74d 100644
--- a/tgl.c
+++ b/tgl.c
@@ -22,6 +22,7 @@
 #include "config.h"
 #endif
 
+#include "crypto/err.h"
 #include "crypto/rsa_pem.h"
 #include "tgl.h"
 #include "tools.h"
@@ -82,10 +83,14 @@ int tgl_init (struct tgl_state *TLS) {
   TLS->message_list.next_use = &TLS->message_list;
   TLS->message_list.prev_use = &TLS->message_list;
 
+  if (TGLC_init (TLS) != 0) {
+    return -1;
+  }
+
   if (tglmp_on_start (TLS) < 0) {
     return -1;
   }
-  
+
   if (!TLS->app_id) {
     TLS->app_id = TG_APP_ID;
     TLS->app_hash = tstrdup (TG_APP_HASH);