Coverage Report

Created: 2023-06-07 06:46

/src/sudo/lib/util/strtonum.c
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Count
Source (jump to first uncovered line)
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/*
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 * SPDX-License-Identifier: ISC
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 *
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 * Copyright (c) 2013-2015, 2019-2020 Todd C. Miller <Todd.Miller@sudo.ws>
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 *
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 * Permission to use, copy, modify, and distribute this software for any
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 * purpose with or without fee is hereby granted, provided that the above
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 * copyright notice and this permission notice appear in all copies.
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 *
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 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
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 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
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 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
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 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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 */
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/*
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 * This is an open source non-commercial project. Dear PVS-Studio, please check it.
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 * PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
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 */
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#include <config.h>
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#include <ctype.h>
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#include <errno.h>
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#include "sudo_compat.h"
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#include "sudo_gettext.h"
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#include "sudo_util.h"
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enum strtonum_err {
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    STN_INITIAL,
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    STN_VALID,
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    STN_INVALID,
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    STN_TOOSMALL,
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    STN_TOOBIG
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};
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/*
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 * Convert a string to a number in the range [minval, maxval]
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 * Unlike strtonum(), this returns the first non-digit in endp (if not NULL).
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 */
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long long
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sudo_strtonumx(const char *str, long long minval, long long maxval, char **endp,
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    const char **errstrp)
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1.77k
{
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1.77k
    enum strtonum_err errval = STN_INITIAL;
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1.77k
    long long lastval, result = 0;
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1.77k
    const char *cp = str;
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1.77k
    unsigned char ch;
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1.77k
    int remainder;
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1.77k
    char sign;
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1.77k
    if (minval > maxval) {
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0
  errval = STN_INVALID;
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0
  goto done;
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0
    }
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    /* Trim leading space and check sign, if any. */
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1.97k
    do {
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1.97k
  ch = *cp++;
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1.97k
    } while (isspace(ch));
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1.77k
    switch (ch) {
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398
    case '-':
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398
  sign = '-';
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398
  ch = *cp++;
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398
  break;
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198
    case '+':
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  ch = *cp++;
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  FALLTHROUGH;
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1.37k
    default:
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1.37k
  sign = '+';
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1.37k
  break;
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1.77k
    }
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    /*
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     * To prevent overflow we determine the highest (or lowest in
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     * the case of negative numbers) value result can have *before*
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     * if its multiplied (divided) by 10 as well as the remainder.
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     * If result matches this value and the next digit is larger than
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     * the remainder, we know the result is out of range.
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     * The remainder is always positive since it is compared against
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     * an unsigned digit.
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     */
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1.77k
    if (sign == '-') {
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398
  lastval = minval / 10;
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398
  remainder = -(minval % 10);
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398
  if (remainder < 0) {
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398
      lastval += 1;
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398
      remainder += 10;
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398
  }
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398
  for (;; ch = *cp++) {
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398
      if (!isdigit(ch))
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195
    break;
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      ch -= '0';
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203
      if (result < lastval || (result == lastval && ch > remainder)) {
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    /* Skip remaining digits. */
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412
    do {
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        ch = *cp++;
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412
    } while (isdigit(ch));
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    errval = STN_TOOSMALL;
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    break;
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203
      } else {
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0
    result *= 10;
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0
    result -= ch;
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0
    errval = STN_VALID;
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0
      }
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203
  }
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398
  if (result > maxval)
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0
      errval = STN_TOOBIG;
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1.37k
    } else {
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1.37k
  lastval = maxval / 10;
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1.37k
  remainder = maxval % 10;
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4.21k
  for (;; ch = *cp++) {
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4.21k
      if (!isdigit(ch))
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964
    break;
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3.25k
      ch -= '0';
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3.25k
      if (result > lastval || (result == lastval && ch > remainder)) {
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    /* Skip remaining digits. */
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610
    do {
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        ch = *cp++;
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610
    } while (isdigit(ch));
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415
    errval = STN_TOOBIG;
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415
    break;
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2.83k
      } else {
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2.83k
    result *= 10;
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2.83k
    result += ch;
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2.83k
    errval = STN_VALID;
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2.83k
      }
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3.25k
  }
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1.37k
  if (result < minval)
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      errval = STN_TOOSMALL;
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1.37k
    }
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1.77k
done:
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1.77k
    switch (errval) {
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195
    case STN_INITIAL:
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885
    case STN_VALID:
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885
  if (errstrp != NULL)
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885
      *errstrp = NULL;
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885
  break;
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0
    case STN_INVALID:
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0
  result = 0;
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0
  errno = EINVAL;
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0
  if (errstrp != NULL)
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0
      *errstrp = N_("invalid value");
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0
  break;
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477
    case STN_TOOSMALL:
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477
  result = 0;
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477
  errno = ERANGE;
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477
  if (errstrp != NULL)
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477
      *errstrp = N_("value too small");
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477
  break;
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415
    case STN_TOOBIG:
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415
  result = 0;
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415
  errno = ERANGE;
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415
  if (errstrp != NULL)
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415
      *errstrp = N_("value too large");
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415
  break;
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1.77k
    }
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1.77k
    if (endp != NULL) {
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1.77k
  if (errval == STN_INITIAL || errval == STN_INVALID)
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195
      *endp = (char *)str;
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1.58k
  else
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1.58k
      *endp = (char *)(cp - 1);
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1.77k
    }
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1.77k
    return result;
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1.77k
}
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/*
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 * Convert a string to a number in the range [minval, maxval]
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 */
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long long
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sudo_strtonum(const char *str, long long minval, long long maxval,
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    const char **errstrp)
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1.77k
{
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1.77k
    const char *errstr;
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1.77k
    char *ep;
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1.77k
    long long ret;
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183
1.77k
    ret = sudo_strtonumx(str, minval, maxval, &ep, &errstr);
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    /* Check for empty string and terminating NUL. */
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1.77k
    if (str == ep || *ep != '\0') {
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417
  errno = EINVAL;
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417
  errstr = N_("invalid value");
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417
  ret = 0;
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417
    }
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1.77k
    if (errstrp != NULL)
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0
  *errstrp = errstr;
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1.77k
    return ret;
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1.77k
}