openssl: basic support for errors and bio objects

Closes https://github.com/espressif/esp-idf/issues/3406

components/openssl/library/ssl_err.c

@@ -0,0 +1,120 @@
+// Copyright 2020 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "ssl_dbg.h"
+
+struct err_error_st {
+    /* file contains the filename where the error occurred. */
+    const char *file;
+    /* packed contains the error library and reason, as packed by ERR_PACK. */
+    uint32_t packed;
+    /* line contains the line number where the error occurred. */
+    uint32_t line;
+};
+
+#define ERR_NUM_ERRORS 4
+
+typedef struct err_state_st {
+    /* errors contains the ERR_NUM_ERRORS most recent errors, organised as a ring
+     * buffer. */
+    struct err_error_st errors[ERR_NUM_ERRORS];
+    /* top contains the index one past the most recent error. If |top| equals
+     * |bottom| then the queue is empty. */
+    unsigned top;
+    /* bottom contains the index of the last error in the queue. */
+    unsigned bottom;
+} ERR_STATE;
+
+#if CONFIG_OPENSSL_ERROR_STACK
+static ERR_STATE s_err_state = { 0 };
+#endif
+
+void ERR_clear_error(void)
+{
+#if CONFIG_OPENSSL_ERROR_STACK
+    memset(&s_err_state.errors[0], 0, sizeof(struct err_state_st));
+    s_err_state.top = s_err_state.bottom = 0;
+#endif
+}
+
+static uint32_t ERR_get_peek_error_internal(const char **file, int *line, bool peak)
+{
+#if CONFIG_OPENSSL_ERROR_STACK
+    if (s_err_state.top == s_err_state.bottom) {
+        return 0;
+    }
+    unsigned new_bottom = (s_err_state.bottom + 1) % ERR_NUM_ERRORS;
+    int err = s_err_state.errors[new_bottom].packed;
+
+    if (file) {
+        *file = s_err_state.errors[new_bottom].file;
+    }
+    if (line) {
+        *line = s_err_state.errors[new_bottom].line;
+    }
+
+    if (peak == false) {
+        memset(&s_err_state.errors[new_bottom], 0, sizeof(struct err_error_st));
+        s_err_state.bottom = new_bottom;
+    }
+
+    return err;
+#else
+    return 0;
+#endif
+}
+
+uint32_t ERR_get_error(void)
+{
+    return ERR_get_peek_error_internal(NULL, NULL, false);
+}
+
+uint32_t ERR_peek_error(void)
+{
+    return ERR_get_peek_error_internal(NULL, NULL, true);
+}
+
+uint32_t ERR_peek_last_error(void)
+{
+    return ERR_get_peek_error_internal(NULL, NULL, true);
+}
+
+uint32_t ERR_peek_error_line_data(const char **file, int *line, const char **data, int *flags)
+{
+    return ERR_get_peek_error_internal(file, line, true);
+}
+
+uint32_t ERR_get_error_line_data(const char **file, int *line, const char **data, int *flags)
+{
+    return ERR_get_peek_error_internal(file, line, false);
+}
+
+const char *ERR_reason_error_string(uint32_t packed_error)
+{
+    return NULL;
+}
+
+void ERR_put_error(int library, int unused, int reason, const char *file, unsigned line)
+{
+#if CONFIG_OPENSSL_ERROR_STACK
+    s_err_state.top = (s_err_state.top + 1) % ERR_NUM_ERRORS;
+    if (s_err_state.top == s_err_state.bottom) {
+        s_err_state.bottom = (s_err_state.bottom + 1) % ERR_NUM_ERRORS;
+    }
+
+    s_err_state.errors[s_err_state.top].packed = (uint32_t)library<<24 | abs(reason);
+    s_err_state.errors[s_err_state.top].file = file;
+    s_err_state.errors[s_err_state.top].line = line;
+#endif
+}