1 files changed, 402 insertions, 0 deletions
diff --git a/library/platform.c b/library/platform.c
new file mode 100644
index 00000000000..890c4cbaba7
--- /dev/null
+++ b/library/platform.c
@@ -0,0 +1,402 @@
+/*
+ *  Platform abstraction layer
+ *
+ *  Copyright The Mbed TLS Contributors
+ *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
+ */
+
+#include "common.h"
+
+#if defined(MBEDTLS_PLATFORM_C)
+
+#include "mbedtls/platform.h"
+#include "mbedtls/platform_util.h"
+#include "mbedtls/error.h"
+
+/* The compile time configuration of memory allocation via the macros
+ * MBEDTLS_PLATFORM_{FREE/CALLOC}_MACRO takes precedence over the runtime
+ * configuration via mbedtls_platform_set_calloc_free(). So, omit everything
+ * related to the latter if MBEDTLS_PLATFORM_{FREE/CALLOC}_MACRO are defined. */
+#if defined(MBEDTLS_PLATFORM_MEMORY) &&                 \
+    !(defined(MBEDTLS_PLATFORM_CALLOC_MACRO) &&        \
+    defined(MBEDTLS_PLATFORM_FREE_MACRO))
+
+#if !defined(MBEDTLS_PLATFORM_STD_CALLOC)
+static void *platform_calloc_uninit(size_t n, size_t size)
+{
+    ((void) n);
+    ((void) size);
+    return NULL;
+}
+
+#define MBEDTLS_PLATFORM_STD_CALLOC   platform_calloc_uninit
+#endif /* !MBEDTLS_PLATFORM_STD_CALLOC */
+
+#if !defined(MBEDTLS_PLATFORM_STD_FREE)
+static void platform_free_uninit(void *ptr)
+{
+    ((void) ptr);
+}
+
+#define MBEDTLS_PLATFORM_STD_FREE     platform_free_uninit
+#endif /* !MBEDTLS_PLATFORM_STD_FREE */
+
+static void * (*mbedtls_calloc_func)(size_t, size_t) = MBEDTLS_PLATFORM_STD_CALLOC;
+static void (*mbedtls_free_func)(void *) = MBEDTLS_PLATFORM_STD_FREE;
+
+void *mbedtls_calloc(size_t nmemb, size_t size)
+{
+    return (*mbedtls_calloc_func)(nmemb, size);
+}
+
+void mbedtls_free(void *ptr)
+{
+    (*mbedtls_free_func)(ptr);
+}
+
+int mbedtls_platform_set_calloc_free(void *(*calloc_func)(size_t, size_t),
+                                     void (*free_func)(void *))
+{
+    mbedtls_calloc_func = calloc_func;
+    mbedtls_free_func = free_func;
+    return 0;
+}
+#endif /* MBEDTLS_PLATFORM_MEMORY &&
+          !( defined(MBEDTLS_PLATFORM_CALLOC_MACRO) &&
+             defined(MBEDTLS_PLATFORM_FREE_MACRO) ) */
+
+#if defined(MBEDTLS_PLATFORM_HAS_NON_CONFORMING_SNPRINTF)
+#include <stdarg.h>
+int mbedtls_platform_win32_snprintf(char *s, size_t n, const char *fmt, ...)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    va_list argp;
+
+    va_start(argp, fmt);
+    ret = mbedtls_vsnprintf(s, n, fmt, argp);
+    va_end(argp);
+
+    return ret;
+}
+#endif
+
+#if defined(MBEDTLS_PLATFORM_SNPRINTF_ALT)
+#if !defined(MBEDTLS_PLATFORM_STD_SNPRINTF)
+/*
+ * Make dummy function to prevent NULL pointer dereferences
+ */
+static int platform_snprintf_uninit(char *s, size_t n,
+                                    const char *format, ...)
+{
+    ((void) s);
+    ((void) n);
+    ((void) format);
+    return 0;
+}
+
+#define MBEDTLS_PLATFORM_STD_SNPRINTF    platform_snprintf_uninit
+#endif /* !MBEDTLS_PLATFORM_STD_SNPRINTF */
+
+int (*mbedtls_snprintf)(char *s, size_t n,
+                        const char *format,
+                        ...) = MBEDTLS_PLATFORM_STD_SNPRINTF;
+
+int mbedtls_platform_set_snprintf(int (*snprintf_func)(char *s, size_t n,
+                                                       const char *format,
+                                                       ...))
+{
+    mbedtls_snprintf = snprintf_func;
+    return 0;
+}
+#endif /* MBEDTLS_PLATFORM_SNPRINTF_ALT */
+
+#if defined(MBEDTLS_PLATFORM_HAS_NON_CONFORMING_VSNPRINTF)
+#include <stdarg.h>
+int mbedtls_platform_win32_vsnprintf(char *s, size_t n, const char *fmt, va_list arg)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+
+    /* Avoid calling the invalid parameter handler by checking ourselves */
+    if (s == NULL || n == 0 || fmt == NULL) {
+        return -1;
+    }
+
+#if defined(_TRUNCATE)
+    ret = vsnprintf_s(s, n, _TRUNCATE, fmt, arg);
+#else
+    ret = vsnprintf(s, n, fmt, arg);
+    if (ret < 0 || (size_t) ret == n) {
+        s[n-1] = '\0';
+        ret = -1;
+    }
+#endif
+
+    return ret;
+}
+#endif
+
+#if defined(MBEDTLS_PLATFORM_VSNPRINTF_ALT)
+#if !defined(MBEDTLS_PLATFORM_STD_VSNPRINTF)
+/*
+ * Make dummy function to prevent NULL pointer dereferences
+ */
+static int platform_vsnprintf_uninit(char *s, size_t n,
+                                     const char *format, va_list arg)
+{
+    ((void) s);
+    ((void) n);
+    ((void) format);
+    ((void) arg);
+    return -1;
+}
+
+#define MBEDTLS_PLATFORM_STD_VSNPRINTF    platform_vsnprintf_uninit
+#endif /* !MBEDTLS_PLATFORM_STD_VSNPRINTF */
+
+int (*mbedtls_vsnprintf)(char *s, size_t n,
+                         const char *format,
+                         va_list arg) = MBEDTLS_PLATFORM_STD_VSNPRINTF;
+
+int mbedtls_platform_set_vsnprintf(int (*vsnprintf_func)(char *s, size_t n,
+                                                         const char *format,
+                                                         va_list arg))
+{
+    mbedtls_vsnprintf = vsnprintf_func;
+    return 0;
+}
+#endif /* MBEDTLS_PLATFORM_VSNPRINTF_ALT */
+
+#if defined(MBEDTLS_PLATFORM_PRINTF_ALT)
+#if !defined(MBEDTLS_PLATFORM_STD_PRINTF)
+/*
+ * Make dummy function to prevent NULL pointer dereferences
+ */
+static int platform_printf_uninit(const char *format, ...)
+{
+    ((void) format);
+    return 0;
+}
+
+#define MBEDTLS_PLATFORM_STD_PRINTF    platform_printf_uninit
+#endif /* !MBEDTLS_PLATFORM_STD_PRINTF */
+
+int (*mbedtls_printf)(const char *, ...) = MBEDTLS_PLATFORM_STD_PRINTF;
+
+int mbedtls_platform_set_printf(int (*printf_func)(const char *, ...))
+{
+    mbedtls_printf = printf_func;
+    return 0;
+}
+#endif /* MBEDTLS_PLATFORM_PRINTF_ALT */
+
+#if defined(MBEDTLS_PLATFORM_FPRINTF_ALT)
+#if !defined(MBEDTLS_PLATFORM_STD_FPRINTF)
+/*
+ * Make dummy function to prevent NULL pointer dereferences
+ */
+static int platform_fprintf_uninit(FILE *stream, const char *format, ...)
+{
+    ((void) stream);
+    ((void) format);
+    return 0;
+}
+
+#define MBEDTLS_PLATFORM_STD_FPRINTF   platform_fprintf_uninit
+#endif /* !MBEDTLS_PLATFORM_STD_FPRINTF */
+
+int (*mbedtls_fprintf)(FILE *, const char *, ...) =
+    MBEDTLS_PLATFORM_STD_FPRINTF;
+
+int mbedtls_platform_set_fprintf(int (*fprintf_func)(FILE *, const char *, ...))
+{
+    mbedtls_fprintf = fprintf_func;
+    return 0;
+}
+#endif /* MBEDTLS_PLATFORM_FPRINTF_ALT */
+
+#if defined(MBEDTLS_PLATFORM_SETBUF_ALT)
+#if !defined(MBEDTLS_PLATFORM_STD_SETBUF)
+/*
+ * Make dummy function to prevent NULL pointer dereferences
+ */
+static void platform_setbuf_uninit(FILE *stream, char *buf)
+{
+    ((void) stream);
+    ((void) buf);
+}
+
+#define MBEDTLS_PLATFORM_STD_SETBUF   platform_setbuf_uninit
+#endif /* !MBEDTLS_PLATFORM_STD_SETBUF */
+void (*mbedtls_setbuf)(FILE *stream, char *buf) = MBEDTLS_PLATFORM_STD_SETBUF;
+
+int mbedtls_platform_set_setbuf(void (*setbuf_func)(FILE *stream, char *buf))
+{
+    mbedtls_setbuf = setbuf_func;
+    return 0;
+}
+#endif /* MBEDTLS_PLATFORM_SETBUF_ALT */
+
+#if defined(MBEDTLS_PLATFORM_EXIT_ALT)
+#if !defined(MBEDTLS_PLATFORM_STD_EXIT)
+/*
+ * Make dummy function to prevent NULL pointer dereferences
+ */
+static void platform_exit_uninit(int status)
+{
+    ((void) status);
+}
+
+#define MBEDTLS_PLATFORM_STD_EXIT   platform_exit_uninit
+#endif /* !MBEDTLS_PLATFORM_STD_EXIT */
+
+void (*mbedtls_exit)(int status) = MBEDTLS_PLATFORM_STD_EXIT;
+
+int mbedtls_platform_set_exit(void (*exit_func)(int status))
+{
+    mbedtls_exit = exit_func;
+    return 0;
+}
+#endif /* MBEDTLS_PLATFORM_EXIT_ALT */
+
+#if defined(MBEDTLS_HAVE_TIME)
+
+#if defined(MBEDTLS_PLATFORM_TIME_ALT)
+#if !defined(MBEDTLS_PLATFORM_STD_TIME)
+/*
+ * Make dummy function to prevent NULL pointer dereferences
+ */
+static mbedtls_time_t platform_time_uninit(mbedtls_time_t *timer)
+{
+    ((void) timer);
+    return 0;
+}
+
+#define MBEDTLS_PLATFORM_STD_TIME   platform_time_uninit
+#endif /* !MBEDTLS_PLATFORM_STD_TIME */
+
+mbedtls_time_t (*mbedtls_time)(mbedtls_time_t *timer) = MBEDTLS_PLATFORM_STD_TIME;
+
+int mbedtls_platform_set_time(mbedtls_time_t (*time_func)(mbedtls_time_t *timer))
+{
+    mbedtls_time = time_func;
+    return 0;
+}
+#endif /* MBEDTLS_PLATFORM_TIME_ALT */
+
+#endif /* MBEDTLS_HAVE_TIME */
+
+#if defined(MBEDTLS_ENTROPY_NV_SEED)
+#if !defined(MBEDTLS_PLATFORM_NO_STD_FUNCTIONS) && defined(MBEDTLS_FS_IO)
+/* Default implementations for the platform independent seed functions use
+ * standard libc file functions to read from and write to a pre-defined filename
+ */
+int mbedtls_platform_std_nv_seed_read(unsigned char *buf, size_t buf_len)
+{
+    FILE *file;
+    size_t n;
+
+    if ((file = fopen(MBEDTLS_PLATFORM_STD_NV_SEED_FILE, "rb")) == NULL) {
+        return -1;
+    }
+
+    /* Ensure no stdio buffering of secrets, as such buffers cannot be wiped. */
+    mbedtls_setbuf(file, NULL);
+
+    if ((n = fread(buf, 1, buf_len, file)) != buf_len) {
+        fclose(file);
+        mbedtls_platform_zeroize(buf, buf_len);
+        return -1;
+    }
+
+    fclose(file);
+    return (int) n;
+}
+
+int mbedtls_platform_std_nv_seed_write(unsigned char *buf, size_t buf_len)
+{
+    FILE *file;
+    size_t n;
+
+    if ((file = fopen(MBEDTLS_PLATFORM_STD_NV_SEED_FILE, "w")) == NULL) {
+        return -1;
+    }
+
+    /* Ensure no stdio buffering of secrets, as such buffers cannot be wiped. */
+    mbedtls_setbuf(file, NULL);
+
+    if ((n = fwrite(buf, 1, buf_len, file)) != buf_len) {
+        fclose(file);
+        return -1;
+    }
+
+    fclose(file);
+    return (int) n;
+}
+#endif /* MBEDTLS_PLATFORM_NO_STD_FUNCTIONS */
+
+#if defined(MBEDTLS_PLATFORM_NV_SEED_ALT)
+#if !defined(MBEDTLS_PLATFORM_STD_NV_SEED_READ)
+/*
+ * Make dummy function to prevent NULL pointer dereferences
+ */
+static int platform_nv_seed_read_uninit(unsigned char *buf, size_t buf_len)
+{
+    ((void) buf);
+    ((void) buf_len);
+    return -1;
+}
+
+#define MBEDTLS_PLATFORM_STD_NV_SEED_READ   platform_nv_seed_read_uninit
+#endif /* !MBEDTLS_PLATFORM_STD_NV_SEED_READ */
+
+#if !defined(MBEDTLS_PLATFORM_STD_NV_SEED_WRITE)
+/*
+ * Make dummy function to prevent NULL pointer dereferences
+ */
+static int platform_nv_seed_write_uninit(unsigned char *buf, size_t buf_len)
+{
+    ((void) buf);
+    ((void) buf_len);
+    return -1;
+}
+
+#define MBEDTLS_PLATFORM_STD_NV_SEED_WRITE   platform_nv_seed_write_uninit
+#endif /* !MBEDTLS_PLATFORM_STD_NV_SEED_WRITE */
+
+int (*mbedtls_nv_seed_read)(unsigned char *buf, size_t buf_len) =
+    MBEDTLS_PLATFORM_STD_NV_SEED_READ;
+int (*mbedtls_nv_seed_write)(unsigned char *buf, size_t buf_len) =
+    MBEDTLS_PLATFORM_STD_NV_SEED_WRITE;
+
+int mbedtls_platform_set_nv_seed(
+    int (*nv_seed_read_func)(unsigned char *buf, size_t buf_len),
+    int (*nv_seed_write_func)(unsigned char *buf, size_t buf_len))
+{
+    mbedtls_nv_seed_read = nv_seed_read_func;
+    mbedtls_nv_seed_write = nv_seed_write_func;
+    return 0;
+}
+#endif /* MBEDTLS_PLATFORM_NV_SEED_ALT */
+#endif /* MBEDTLS_ENTROPY_NV_SEED */
+
+#if !defined(MBEDTLS_PLATFORM_SETUP_TEARDOWN_ALT)
+/*
+ * Placeholder platform setup that does nothing by default
+ */
+int mbedtls_platform_setup(mbedtls_platform_context *ctx)
+{
+    (void) ctx;
+
+    return 0;
+}
+
+/*
+ * Placeholder platform teardown that does nothing by default
+ */
+void mbedtls_platform_teardown(mbedtls_platform_context *ctx)
+{
+    (void) ctx;
+}
+#endif /* MBEDTLS_PLATFORM_SETUP_TEARDOWN_ALT */
+
+#endif /* MBEDTLS_PLATFORM_C */