SCA hardening for mod. field inversion in EC_GROUP

[oweals/openssl.git] / crypto / err / err.c

diff --git a/crypto/err/err.c b/crypto/err/err.c
index 66a60e907cd96b766b2779e19e827566ece13c9e..48d8cfabf242fa4dc407bccfe24e721aeffd711c 100644 (file)
--- a/crypto/err/err.c
+++ b/crypto/err/err.c
@@ -21,6 +21,7 @@
 #include "internal/thread_once.h"
 #include "internal/ctype.h"
 #include "internal/constant_time_locl.h"
+#include "e_os.h"
 
 static int err_load_strings(const ERR_STRING_DATA *str);
 
@@ -206,6 +207,7 @@ static void build_SYS_str_reasons(void)
     size_t cnt = 0;
     static int init = 1;
     int i;
+    int saveerrno = get_last_sys_error();
 
     CRYPTO_THREAD_write_lock(err_string_lock);
     if (!init) {
@@ -251,6 +253,8 @@ static void build_SYS_str_reasons(void)
     init = 0;
 
     CRYPTO_THREAD_unlock(err_string_lock);
+    /* openssl_strerror_r could change errno, but we want to preserve it */
+    set_sys_error(saveerrno);
     err_load_strings(SYS_str_reasons);
 }
 #endif
@@ -693,6 +697,7 @@ DEFINE_RUN_ONCE_STATIC(err_do_init)
 ERR_STATE *ERR_get_state(void)
 {
     ERR_STATE *state;
+    int saveerrno = get_last_sys_error();
 
     if (!OPENSSL_init_crypto(OPENSSL_INIT_BASE_ONLY, NULL))
         return NULL;
@@ -724,6 +729,7 @@ ERR_STATE *ERR_get_state(void)
         OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CRYPTO_STRINGS, NULL);
     }
 
+    set_sys_error(saveerrno);
     return state;
 }
 
@@ -733,6 +739,20 @@ ERR_STATE *ERR_get_state(void)
  */
 int err_shelve_state(void **state)
 {
+    int saveerrno = get_last_sys_error();
+
+    /*
+     * Note, at present our only caller is OPENSSL_init_crypto(), indirectly
+     * via ossl_init_load_crypto_nodelete(), by which point the requested
+     * "base" initialization has already been performed, so the below call is a
+     * NOOP, that re-enters OPENSSL_init_crypto() only to quickly return.
+     *
+     * If are no other valid callers of this function, the call below can be
+     * removed, avoiding the re-entry into OPENSSL_init_crypto().  If there are
+     * potential uses that are not from inside OPENSSL_init_crypto(), then this
+     * call is needed, but some care is required to make sure that the re-entry
+     * remains a NOOP.
+     */
     if (!OPENSSL_init_crypto(OPENSSL_INIT_BASE_ONLY, NULL))
         return 0;
 
@@ -743,6 +763,7 @@ int err_shelve_state(void **state)
     if (!CRYPTO_THREAD_set_local(&err_thread_local, (ERR_STATE*)-1))
         return 0;
 
+    set_sys_error(saveerrno);
     return 1;
 }
 
@@ -769,20 +790,31 @@ int ERR_get_next_error_library(void)
     return ret;
 }
 
-void ERR_set_error_data(char *data, int flags)
+static int err_set_error_data_int(char *data, int flags)
 {
     ERR_STATE *es;
     int i;
 
     es = ERR_get_state();
     if (es == NULL)
-        return;
+        return 0;
 
     i = es->top;
 
     err_clear_data(es, i);
     es->err_data[i] = data;
     es->err_data_flags[i] = flags;
+
+    return 1;
+}
+
+void ERR_set_error_data(char *data, int flags)
+{
+    /*
+     * This function is void so we cannot propagate the error return. Since it
+     * is also in the public API we can't change the return type.
+     */
+    err_set_error_data_int(data, flags);
 }
 
 void ERR_add_error_data(int num, ...)
@@ -822,7 +854,8 @@ void ERR_add_error_vdata(int num, va_list args)
         }
         OPENSSL_strlcat(str, a, (size_t)s + 1);
     }
-    ERR_set_error_data(str, ERR_TXT_MALLOCED | ERR_TXT_STRING);
+    if (!err_set_error_data_int(str, ERR_TXT_MALLOCED | ERR_TXT_STRING))
+        OPENSSL_free(str);
 }
 
 int ERR_set_mark(void)
@@ -880,6 +913,25 @@ int ERR_clear_last_mark(void)
     return 1;
 }
 
+#ifdef UINTPTR_T
+# undef UINTPTR_T
+#endif
+/*
+ * uintptr_t is the answer, but unfortunately C89, current "least common
+ * denominator" doesn't define it. Most legacy platforms typedef it anyway,
+ * so that attempt to fill the gaps means that one would have to identify
+ * that track these gaps, which would be undesirable. Macro it is...
+ */
+#if defined(__VMS) && __INITIAL_POINTER_SIZE==64
+/*
+ * But we can't use size_t on VMS, because it adheres to sizeof(size_t)==4
+ * even in 64-bit builds, which means that it won't work as mask.
+ */
+# define UINTPTR_T unsigned long long
+#else
+# define UINTPTR_T size_t
+#endif
+
 void err_clear_last_constant_time(int clear)
 {
     ERR_STATE *es;
@@ -893,8 +945,8 @@ void err_clear_last_constant_time(int clear)
 
     es->err_flags[top] &= ~(0 - clear);
     es->err_buffer[top] &= ~(0UL - clear);
-    es->err_file[top] = (const char *)((uintptr_t)es->err_file[top] &
-                                       ~((uintptr_t)0 - clear));
+    es->err_file[top] = (const char *)((UINTPTR_T)es->err_file[top] &
+                                       ~((UINTPTR_T)0 - clear));
     es->err_line[top] |= 0 - clear;
 
     es->top = (top + ERR_NUM_ERRORS - clear) % ERR_NUM_ERRORS;