path: root/tapset/conversions.stp

// conversions tapset
// Copyright (C) 2005-2010 Red Hat Inc.
// Copyright (C) 2007 Intel Corporation.
//
// This file is part of systemtap, and is free software.  You can
// redistribute it and/or modify it under the terms of the GNU General
// Public License (GPL); either version 2, or (at your option) any
// later version.

/**
 * sfunction kernel_string - Retrieves string from kernel memory.
 * @addr: The kernel address to retrieve the string from.
 *
 * Description: Returns the null terminated C string from a given kernel
 * memory address. Reports an error on string copy fault.
 */
function kernel_string:string (addr:long) %{ /* pure */
  char *destination = THIS->__retvalue;
  deref_string (destination, THIS->addr, MAXSTRINGLEN);
  if (0) {
deref_fault: /* branched to from deref_string() */
    snprintf (CONTEXT->error_buffer, sizeof(CONTEXT->error_buffer),
        "kernel string copy fault at 0x%p", (void *) (uintptr_t) THIS->addr);
    CONTEXT->last_error = CONTEXT->error_buffer;
  }
%}

/**
 * sfunction kernel_string_n - Retrieves string of given length from kernel memory.
 * @addr: The kernel address to retrieve the string from.
 * @n: The maximum length of the string (if not null terminated).
 *
 * Description: Returns the C string of a maximum given length from a
 * given kernel memory address. Reports an error on string copy fault.
 */
function kernel_string_n:string (addr:long, n:long) %{ /* pure */
  char *destination = THIS->__retvalue;
  int64_t len = clamp_t(int64_t, THIS->n + 1, 1, MAXSTRINGLEN);
  deref_string (destination, THIS->addr, len);
  if (0) {
deref_fault: /* branched to from deref_string() */
    snprintf (CONTEXT->error_buffer, sizeof(CONTEXT->error_buffer),
        "kernel string copy fault at 0x%p", (void *) (uintptr_t) THIS->addr);
    CONTEXT->last_error = CONTEXT->error_buffer;
  }
%}

/**
 * sfunction kernel_long - Retrieves a long value stored in kernel memory.
 * @addr: The kernel address to retrieve the long from.
 *
 * Description: Returns the long value from a given kernel memory address.
 * Reports an error when reading from the given address fails.
 */
function kernel_long:long (addr:long) %{ /* pure */
  THIS->__retvalue = kread((long *) (intptr_t) THIS->addr);
  if (0) {
deref_fault: /* branched to from kread() */
    snprintf (CONTEXT->error_buffer, sizeof(CONTEXT->error_buffer),
        "kernel long copy fault at 0x%p", (void *) (uintptr_t) THIS->addr);
    CONTEXT->last_error = CONTEXT->error_buffer;
  }
%}

/**
 * sfunction kernel_int - Retrieves an int value stored in kernel memory.
 * @addr: The kernel address to retrieve the int from.
 *
 * Description: Returns the int value from a given kernel memory address.
 * Reports an error when reading from the given address fails.
 */
function kernel_int:long (addr:long) %{ /* pure */
  THIS->__retvalue = kread((int *) (intptr_t) THIS->addr);
  if (0) {
deref_fault: /* branched to from kread() */
    snprintf (CONTEXT->error_buffer, sizeof(CONTEXT->error_buffer),
        "kernel int copy fault at 0x%p", (void *) (uintptr_t) THIS->addr);
    CONTEXT->last_error = CONTEXT->error_buffer;
  }
%}

/**
 * sfunction kernel_short - Retrieves a short value stored in kernel memory.
 * @addr: The kernel address to retrieve the short from.
 *
 * Description: Returns the short value from a given kernel memory address.
 * Reports an error when reading from the given address fails.
 */
function kernel_short:long (addr:long) %{ /* pure */
  THIS->__retvalue = kread((short *) (intptr_t) THIS->addr);
  if (0) {
deref_fault: /* branched to from kread() */
    snprintf (CONTEXT->error_buffer, sizeof(CONTEXT->error_buffer),
        "kernel short copy fault at 0x%p", (void *) (uintptr_t) THIS->addr);
    CONTEXT->last_error = CONTEXT->error_buffer;
  }
%}

/**
 * sfunction kernel_char - Retrieves a char value stored in kernel memory.
 * @addr: The kernel address to retrieve the char from.
 *
 * Description: Returns the char value from a given kernel memory address.
 * Reports an error when reading from the given address fails.
 */
function kernel_char:long (addr:long) %{ /* pure */
  THIS->__retvalue = kread((char *) (intptr_t) THIS->addr);
  if (0) {
deref_fault: /* branched to from kread() */
    snprintf (CONTEXT->error_buffer, sizeof(CONTEXT->error_buffer),
        "kernel char copy fault at 0x%p", (void *) (uintptr_t) THIS->addr);
    CONTEXT->last_error = CONTEXT->error_buffer;
  }
%}

/**
 * sfunction kernel_pointer - Retrieves a pointer value stored in
 * kernel memory.
 * @addr: The kernel address to retrieve the pointer from.
 *
 * Description: Returns the pointer value from a given kernel memory
 * address. Reports an error when reading from the given address
 * fails.
 */
function kernel_pointer:long (addr:long) %{ /* pure */
  THIS->__retvalue = (int64_t) kread((void **) (intptr_t) THIS->addr);
  if (0) {
deref_fault: /* branched to from kread() */
    snprintf (CONTEXT->error_buffer, sizeof(CONTEXT->error_buffer),
        "kernel pointer copy fault at 0x%p", (void *) (uintptr_t) THIS->addr);
    CONTEXT->last_error = CONTEXT->error_buffer;
  }
%}

/**
 * sfunction user_string - Retrieves string from user space.
 * @addr: The user space address to retrieve the string from.
 *
 * Description: Returns the null terminated C string from a given user space
 * memory address. Reports "<unknown>" on the rare cases when userspace
 * data is not accessible.
 */
function user_string:string (addr:long) { return user_string2 (addr, "<unknown>") }

/**
 * sfunction user_string2 - Retrieves string from user space with alternative error string..
 * @addr: The user space address to retrieve the string from.
 * @err_msg: The error message to return when data isn't available.
 *
 * Description: Returns the null terminated C string from a given user space
 * memory address. Reports the given error message on the rare cases when
 * userspace data is not accessible.
 */
function user_string2:string (addr:long, err_msg:string) %{ /* pure */ /* unprivileged */
  assert_is_myproc();
  if (_stp_strncpy_from_user (THIS->__retvalue, 
        (const char __user*) (uintptr_t) THIS->addr,
        MAXSTRINGLEN) < 0)
    strlcpy (THIS->__retvalue, THIS->err_msg, MAXSTRINGLEN);
%}

/**
 * sfunction user_string_warn - Retrieves string from user space.
 * @addr: The user space address to retrieve the string from.
 *
 * Description: Returns the null terminated C string from a given user space
 * memory address. Reports "<unknown>" on the rare cases when userspace
 * data is not accessible and warns (but does not abort) about the failure.
 */
function user_string_warn:string (addr:long) %{ /* pure */ /* unprivileged */
  long rc;
  assert_is_myproc();
  rc = _stp_strncpy_from_user (THIS->__retvalue,
      (const char __user*) (uintptr_t) THIS->addr, MAXSTRINGLEN);
  if (rc < 0) {
    // NB: using error_buffer to get local space for the warning, but we're
    // not aborting, so leave last_error alone.
    snprintf (CONTEXT->error_buffer, sizeof(CONTEXT->error_buffer),
        "user string copy fault %ld at %p", rc,
        (void *) (uintptr_t) THIS->addr);
    _stp_warn(CONTEXT->error_buffer);
    strlcpy (THIS->__retvalue, "<unknown>", MAXSTRINGLEN);
  }
%}

/**
 * sfunction user_string_quoted - Retrieves and quotes string from user space.
 * @addr: The user space address to retrieve the string from.
 *
 * Description: Returns the null terminated C string from a given user space
 * memory address where any ASCII characters that are not printable are
 * replaced by the corresponding escape sequence in the returned string.
 * Reports "NULL" for address zero. Returns "<unknown>" on the rare
 * cases when userspace data is not accessible at the given address.
 */
function user_string_quoted:string (addr:long) %{ /* pure */ /* unprivileged */
  assert_is_myproc();
  if (THIS->addr == 0)	
    strlcpy (THIS->__retvalue, "NULL", MAXSTRINGLEN);
  else
    /* XXX: stp_text_str uses sleepy __get_user() => unsafe ?!  */
    _stp_text_str(THIS->__retvalue, (char *)(uintptr_t)THIS->addr,
        MAXSTRINGLEN, 1, 1);
%}

/**
 * sfunction user_string_n - Retrieves string of given length from user space.
 * @addr: The user space address to retrieve the string from.
 * @n: The maximum length of the string (if not null terminated).
 *
 * Description: Returns the C string of a maximum given length from a
 * given user space address. Returns "<unknown>" on the rare cases
 * when userspace data is not accessible at the given address.
 */
function user_string_n:string (addr:long, n:long) {
	return user_string_n2(addr, n, "<unknown>")
}
	
/**
 * sfunction user_string_n2 - Retrieves string of given length from user space.
 * @addr: The user space address to retrieve the string from.
 * @n: The maximum length of the string (if not null terminated).
 * @err_msg: The error message to return when data isn't available.
 *
 * Description: Returns the C string of a maximum given length from a
 * given user space address. Returns the given error message string on
 * the rare cases when userspace data is not accessible at the given address.
 */
function user_string_n2:string (addr:long, n:long, err_msg:string) %{ /* pure */ /* unprivileged */
	int64_t len = clamp_t(int64_t, THIS->n + 1, 1, MAXSTRINGLEN);
        assert_is_myproc();
	if (_stp_strncpy_from_user(THIS->__retvalue,
				(char __user *) (uintptr_t) THIS->addr,
				len) < 0)
		strlcpy(THIS->__retvalue, THIS->err_msg, MAXSTRINGLEN);
	else
		THIS->__retvalue[len - 1] = '\0';
%}

/**
 * sfunction user_string_n_warn - Retrieves string from user space.
 * @addr: The user space address to retrieve the string from.
 * @n: The maximum length of the string (if not null terminated).
 *
 * Description: Returns up to n characters of a C string from a given
 * user space memory address. Reports "<unknown>" on the rare cases
 * when userspace data is not accessible and warns (but does not abort)
 * about the failure.
 */
function user_string_n_warn:string (addr:long, n:long) %{ /* pure */ /* unprivileged */
	int64_t len = clamp_t(int64_t, THIS->n + 1, 1, MAXSTRINGLEN);
	long rc;

        assert_is_myproc();
	rc = _stp_strncpy_from_user(THIS->__retvalue,
			(char __user *) (uintptr_t) THIS->addr, len);
	if (rc < 0) {
		// NB: using error_buffer to get local space for the warning, but we're
		// not aborting, so leave last_error alone.
		snprintf (CONTEXT->error_buffer, sizeof(CONTEXT->error_buffer),
				"user string copy fault %ld at %p", rc,
				(void *) (uintptr_t) THIS->addr);
		_stp_warn(CONTEXT->error_buffer);
		strlcpy (THIS->__retvalue, "<unknown>", MAXSTRINGLEN);
	} else
		THIS->__retvalue[len - 1] = '\0';
%}

/**
 * sfunction user_string_quoted - Retrieves and quotes string from user space.
 * @addr: The user space address to retrieve the string from.
 * @n: The maximum length of the string (if not null terminated).
 *
 * Description: Returns up to n characters of a C string from the given
 * user space memory address where any ASCII characters that are not
 * printable are replaced by the corresponding escape sequence in the
 * returned string. Reports "NULL" for address zero. Returns "<unknown>"
 * on the rare cases when userspace data is not accessible at the given
 * address.
 */
function user_string_n_quoted:string (addr:long, n:long) %{ /* pure */ /* unprivileged */
        int64_t len = clamp_t(int64_t, THIS->n + 1, 1, MAXSTRINGLEN);
        assert_is_myproc();
	if (THIS->addr == 0)
		strlcpy(THIS->__retvalue, "NULL", MAXSTRINGLEN);
	else
		/* XXX: stp_text_str uses sleepy __get_user() => unsafe ?!  */
		_stp_text_str(THIS->__retvalue, (char *)(uintptr_t)THIS->addr,
				len, 1, 1);
%}

/**
 * sfunction user_short - Retrieves a short value stored in user space.
 * @addr: The user space address to retrieve the short from.
 *
 * Description: Returns the short value from a given user space address.
 * Returns zero when user space data is not accessible.
 */
function user_short:long (addr:long) %{ /* pure */ /* unprivileged */
        assert_is_myproc();
	if (!access_ok(VERIFY_READ, (short *) (intptr_t) THIS->addr, sizeof(short)))
		goto fault;
	if (__stp_get_user(THIS->__retvalue, (short *) (intptr_t) THIS->addr)) {
fault:
		THIS->__retvalue = 0;
	}
%}

/**
 * sfunction user_short_warn - Retrieves a short value stored in user space.
 * @addr: The user space address to retrieve the short from.
 *
 * Description: Returns the short value from a given user space address.
 * Returns zero when user space and warns (but does not abort) about the
 * failure.
 */
function user_short_warn:long (addr:long) %{ /* pure */ /* unprivileged */
        assert_is_myproc();
	if (!access_ok(VERIFY_READ, (short *) (intptr_t) THIS->addr, sizeof(short)))
		goto fault;
	if (__stp_get_user(THIS->__retvalue, (short *) (intptr_t) THIS->addr)) {
fault:
		snprintf (CONTEXT->error_buffer, sizeof(CONTEXT->error_buffer),
				"user short copy fault %p", (void *) (uintptr_t) THIS->addr);
		_stp_warn(CONTEXT->error_buffer);
		THIS->__retvalue = 0;
	}
%}

/**
 * sfunction user_int - Retrieves an int value stored in user space.
 * @addr: The user space address to retrieve the int from.
 *
 * Description: Returns the int value from a given user space address.
 * Returns zero when user space data is not accessible.
 */
function user_int:long (addr:long) %{ /* pure */ /* unprivileged */
        assert_is_myproc();
	if (!access_ok(VERIFY_READ, (int *) (intptr_t) THIS->addr, sizeof(int)))
		goto fault;
	if (__stp_get_user(THIS->__retvalue, (int *) (intptr_t) THIS->addr)) {
fault:
		THIS->__retvalue = 0;
	}
%}

/**
 * sfunction user_int_warn - Retrieves an int value stored in user space.
 * @addr: The user space address to retrieve the int from.
 *
 * Description: Returns the int value from a given user space address.
 * Returns zero when user space and warns (but does not abort) about the
 * failure.
 */
function user_int_warn:long (addr:long) %{ /* pure */ /* unprivileged */
        assert_is_myproc();
	if (!access_ok(VERIFY_READ, (int *) (intptr_t) THIS->addr, sizeof(int)))
		goto fault;
	if (__stp_get_user(THIS->__retvalue, (int *) (intptr_t) THIS->addr)) {
fault:
		snprintf (CONTEXT->error_buffer, sizeof(CONTEXT->error_buffer),
				"user int copy fault %p", (void *) (uintptr_t) THIS->addr);
		_stp_warn(CONTEXT->error_buffer);
		THIS->__retvalue = 0;
	}
%}

/**
 * sfunction user_long - Retrieves a long value stored in user space.
 * @addr: The user space address to retrieve the long from.
 *
 * Description: Returns the long value from a given user space address.
 * Returns zero when user space data is not accessible.
 */
function user_long:long (addr:long) %{ /* pure */ /* unprivileged */
        assert_is_myproc();
	if (!access_ok(VERIFY_READ, (long *) (intptr_t) THIS->addr, sizeof(long)))
		goto fault;
	if (__stp_get_user(THIS->__retvalue, (long *) (intptr_t) THIS->addr)) {
fault:
		THIS->__retvalue = 0;
	}
%}

/**
 * sfunction user_long_warn - Retrieves a long value stored in user space.
 * @addr: The user space address to retrieve the long from.
 *
 * Description: Returns the long value from a given user space address.
 * Returns zero when user space and warns (but does not abort) about the
 * failure.
 */
function user_long_warn:long (addr:long) %{ /* pure */ /* unprivileged */
        assert_is_myproc();
	if (!access_ok(VERIFY_READ, (long *) (intptr_t) THIS->addr, sizeof(long)))
		goto fault;
	if (__stp_get_user(THIS->__retvalue, (long *) (intptr_t) THIS->addr)) {
fault:
		snprintf (CONTEXT->error_buffer, sizeof(CONTEXT->error_buffer),
				"user long copy fault %p", (void *) (uintptr_t) THIS->addr);
		_stp_warn(CONTEXT->error_buffer);
		THIS->__retvalue = 0;
	}
%}

/**
 * sfunction user_char - Retrieves a char value stored in user space.
 * @addr: The user space address to retrieve the char from.
 *
 * Description: Returns the char value from a given user space address.
 * Returns zero when user space data is not accessible.
 */
function user_char:long (addr:long) %{ /* pure */ /* unprivileged */
        assert_is_myproc();
	if (!access_ok(VERIFY_READ, (char *) (intptr_t) THIS->addr, sizeof(char)))
		goto fault;
	if (__stp_get_user(THIS->__retvalue, (char *) (intptr_t) THIS->addr)) {
fault:
		THIS->__retvalue = 0;
	}
%}

/**
 * sfunction user_char_warn - Retrieves a char value stored in user space.
 * @addr: The user space address to retrieve the char from.
 *
 * Description: Returns the char value from a given user space address.
 * Returns zero when user space and warns (but does not abort) about the
 * failure.
 */
function user_char_warn:long (addr:long) %{ /* pure */ /* unprivileged */
        assert_is_myproc();
	if (!access_ok(VERIFY_READ, (char *) (intptr_t) THIS->addr, sizeof(char)))
		goto fault;
	if (__stp_get_user(THIS->__retvalue, (char *) (intptr_t) THIS->addr)) {
fault:
		snprintf (CONTEXT->error_buffer, sizeof(CONTEXT->error_buffer),
				"user char copy fault %p", (void *) (uintptr_t) THIS->addr);
		_stp_warn(CONTEXT->error_buffer);
		THIS->__retvalue = 0;
	}
%}