Merge pull request #109 from flocke/master

steam_rsa: add libgcrypt as crypto backend

2 files changed, 178 insertions, 5 deletions

diff --git a/steam-mobile/Makefile b/steam-mobile/Makefile
index 5c4ed38..fee9927 100644
--- a/steam-mobile/Makefile
+++ b/steam-mobile/Makefile
@@ -2,8 +2,23 @@
 COMPILER = gcc
 PKG_CONFIG ?= pkg-config
 
-LIBPURPLE_CFLAGS += $(shell ${PKG_CONFIG} --cflags glib-2.0 json-glib-1.0 purple nss gnome-keyring-1)
-LIBPURPLE_LIBS += $(shell ${PKG_CONFIG} --libs glib-2.0 json-glib-1.0 purple nss)
+# Global libraries
+LIBPURPLE_CFLAGS += $(shell ${PKG_CONFIG} --cflags glib-2.0 json-glib-1.0 purple gnome-keyring-1)
+LIBPURPLE_LIBS += $(shell ${PKG_CONFIG} --libs glib-2.0 json-glib-1.0 purple)
+
+CFLAGS = ${LIBPURPLE_CFLAGS}
+LIBS = ${LIBPURPLE_LIBS}
+
+# Crypt backend to use
+CRYPT_BACKEND = nss
+
+ifeq (${CRYPT_BACKEND}, nss)
+	CFLAGS += $(shell ${PKG_CONFIG} --cflags nss)
+	LIBS += $(shell ${PKG_CONFIG} --libs nss)
+else ifeq (${CRYPT_BACKEND}, gcrypt)
+	CFLAGS += $(shell libgcrypt-config --cflags) -DUSE_GCRYPT_CRYPTO
+	LIBS += $(shell libgcrypt-config --libs)
+endif
 
 STEAM_SOURCES = \
 	steam_connection.c \
@@ -15,4 +30,4 @@ clean:
 	rm -f libsteam.so
 
 libsteam.so: ${STEAM_SOURCES}
-	${COMPILER} -Wall -I. -g -O2 -fPIC -pipe ${STEAM_SOURCES} -o $@ ${LIBPURPLE_CFLAGS} ${LIBPURPLE_LIBS} -shared
+	${COMPILER} -Wall -I. -g -O2 -fPIC -pipe ${STEAM_SOURCES} -o $@ ${CFLAGS} ${LIBS} -shared
diff --git a/steam-mobile/steam_rsa.c b/steam-mobile/steam_rsa.c
index 9706fc8..67ee9da 100644
--- a/steam-mobile/steam_rsa.c
+++ b/steam-mobile/steam_rsa.c
@@ -13,7 +13,7 @@ password=<base64rsaencryptedpwd>&username=<steamusername>&emailauth=&captchagid=
 #undef USE_OPENSSL_CRYPTO

 #endif

 

-#if !defined USE_POLARSSL_CRYPTO && !defined USE_OPENSSL_CRYPTO && !defined USE_NSS_CRYPTO

+#if !defined USE_POLARSSL_CRYPTO && !defined USE_OPENSSL_CRYPTO && !defined USE_NSS_CRYPTO && !defined USE_GCRYPT_CRYPTO

 #define USE_NSS_CRYPTO

 #endif

 

@@ -138,6 +138,164 @@ steam_encrypt_password(const gchar *modulus_str, const gchar *exponent_str, cons
 	return output;

 }

 

+#elif defined USE_GCRYPT_CRYPTO

+

+#include <gcrypt.h>

+#include <string.h>

+

+// The following functions steam_util_str_hex2bytes, steam_crypt_rsa_enc and steam_encrypt_password

+// (originally steam_crypt_rsa_enc_str) have been taken directly from steam-util.c and steam-crypt.c

+// from the bitlbee-steam source code. The original files are released under the GNU General Public

+// License version 2 and can be found at https://github.com/jgeboski/bitlbee-steam.

+// All credit goes to the original author of bitlbee-steam, James Geboski <jgeboski@gmail.com>.

+

+GByteArray *

+steam_util_str_hex2bytes(const gchar *str)

+{

+  GByteArray *ret;

+  gboolean    hax;

+  gsize       size;

+  gchar       val;

+  guint       i;

+  guint       d;

+

+  g_return_val_if_fail(str != NULL, NULL);

+

+  size = strlen(str);

+  hax  = (size % 2) != 0;

+

+  ret = g_byte_array_new();

+  g_byte_array_set_size(ret, (size + 1) / 2);

+  memset(ret->data, 0, ret->len);

+

+  for (d = i = 0; i < size; i++, hax = !hax) {

+    val = g_ascii_xdigit_value(str[i]);

+

+    if (val < 0) {

+      g_byte_array_free(ret, TRUE);

+      return NULL;

+    }

+

+    if (hax)

+      ret->data[d++] |= val & 0x0F;

+    else

+      ret->data[d] |= (val << 4) & 0xF0;

+  }

+

+  return ret;

+}

+

+GByteArray *

+steam_crypt_rsa_enc(const GByteArray *mod, const GByteArray *exp, const GByteArray *bytes)

+{

+  GByteArray   *ret;

+  gcry_mpi_t    mmpi;

+  gcry_mpi_t    empi;

+  gcry_mpi_t    dmpi;

+  gcry_sexp_t   kata;

+  gcry_sexp_t   data;

+  gcry_sexp_t   cata;

+  gcry_error_t  res;

+  gsize         size;

+

+  g_return_val_if_fail(mod   != NULL, NULL);

+  g_return_val_if_fail(exp   != NULL, NULL);

+  g_return_val_if_fail(bytes != NULL, NULL);

+

+  mmpi = empi = dmpi = NULL;

+  kata = data = cata = NULL;

+  ret  = NULL;

+

+  res  = gcry_mpi_scan(&mmpi, GCRYMPI_FMT_USG, mod->data, mod->len, NULL);

+  res |= gcry_mpi_scan(&empi, GCRYMPI_FMT_USG, exp->data, exp->len, NULL);

+  res |= gcry_mpi_scan(&dmpi, GCRYMPI_FMT_USG, bytes->data, bytes->len, NULL);

+

+  if (G_LIKELY(res == 0)) {

+    res  = gcry_sexp_build(&kata, NULL, "(public-key(rsa(n %m)(e %m)))", mmpi, empi);

+    res |= gcry_sexp_build(&data, NULL, "(data(flags pkcs1)(value %m))", dmpi);

+

+    if (G_LIKELY(res == 0)) {

+      res = gcry_pk_encrypt(&cata, data, kata);

+

+      if (G_LIKELY(res == 0)) {

+        gcry_sexp_release(data);

+        data = gcry_sexp_find_token(cata, "a", 0);

+

+        if (G_LIKELY(data != NULL)) {

+          gcry_mpi_release(dmpi);

+          dmpi = gcry_sexp_nth_mpi(data, 1, GCRYMPI_FMT_USG);

+

+          if (G_LIKELY(dmpi != NULL)) {

+            ret = g_byte_array_new();

+            g_byte_array_set_size(ret, mod->len);

+

+            gcry_mpi_print(GCRYMPI_FMT_USG, ret->data, ret->len, &size, dmpi);

+

+            g_warn_if_fail(size <= mod->len);

+            g_byte_array_set_size(ret, size);

+          } else {

+            g_warn_if_reached();

+          }

+        } else {

+          g_warn_if_reached();

+        }

+      }

+    }

+  }

+

+  gcry_sexp_release(cata);

+  gcry_sexp_release(data);

+  gcry_sexp_release(kata);

+

+  gcry_mpi_release(dmpi);

+  gcry_mpi_release(empi);

+  gcry_mpi_release(mmpi);

+

+  return ret;

+}

+

+gchar *

+steam_encrypt_password(const gchar *mod, const gchar *exp, const gchar *str)

+{

+  GByteArray *bytes;

+  GByteArray *mytes;

+  GByteArray *eytes;

+  GByteArray *enc;

+  gchar      *ret;

+

+  g_return_val_if_fail(mod != NULL, NULL);

+  g_return_val_if_fail(exp != NULL, NULL);

+  g_return_val_if_fail(str != NULL, NULL);

+

+  mytes = steam_util_str_hex2bytes(mod);

+

+  if (G_UNLIKELY(mytes == NULL))

+    return NULL;

+

+  eytes = steam_util_str_hex2bytes(exp);

+

+  if (G_UNLIKELY(eytes == NULL)) {

+    g_byte_array_free(mytes, TRUE);

+    return NULL;

+  }

+

+  bytes = g_byte_array_new();

+  g_byte_array_append(bytes, (guint8*) str, strlen(str));

+  enc = steam_crypt_rsa_enc(mytes, eytes, bytes);

+

+  g_byte_array_free(bytes, TRUE);

+  g_byte_array_free(eytes, TRUE);

+  g_byte_array_free(mytes, TRUE);

+

+  if (G_UNLIKELY(enc == NULL))

+    return NULL;

+

+  ret = g_base64_encode(enc->data, enc->len);

+  g_byte_array_free(enc, TRUE);

+

+  return ret;

+}

+

 #elif defined USE_POLARSSL_CRYPTO

 

 #include "polarssl/config.h"

@@ -280,4 +438,4 @@ steam_encrypt_password(const gchar *modulus_str, const gchar *exponent_str, cons
 	return output;

 }

 

-#endif
\ No newline at end of file
+#endif