Merge pull request #155 from ionspin/152-invalid-string-parsed

Check for base, and check if character belongs to base. Fixes #152
ionspin · Feb 11, 2021 · fa306ad · fa306ad
2 parents abbc0a1 + 54bd3f7
commit fa306ad
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Showing 6 changed files with 31 additions and 5 deletions.
diff --git a/bignum/src/commonMain/kotlin/com/ionspin/kotlin/bignum/integer/BigInteger.kt b/bignum/src/commonMain/kotlin/com/ionspin/kotlin/bignum/integer/BigInteger.kt
@@ -74,6 +74,9 @@ class BigInteger internal constructor(wordArray: WordArray, requestedSign: Sign)
         val LOG_10_OF_2 = log10(2.0)
 
         override fun parseString(string: String, base: Int): BigInteger {
+            if (base < 2 || base > 36) {
+                throw NumberFormatException("Unsupported base: $base. Supported base range is from 2 to 36")
+            }
             val decimal = string.contains('.')
             if (decimal) {
                 val bigDecimal = BigDecimal.parseString(string)

diff --git a/.../src/commonMain/kotlin/com/ionspin/kotlin/bignum/integer/base32/BigInteger32Arithmetic.kt b/.../src/commonMain/kotlin/com/ionspin/kotlin/bignum/integer/base32/BigInteger32Arithmetic.kt
@@ -1052,7 +1052,7 @@ internal object BigInteger32Arithmetic : BigInteger32ArithmeticInterface {
     override fun parseForBase(number: String, base: Int): UIntArray {
         var parsed = ZERO
         number.forEach { char ->
-            parsed = (parsed * base.toUInt()) + char.toDigit().toUInt()
+            parsed = (parsed * base.toUInt()) + char.toDigit(base).toUInt()
         }
         return parsed
     }

diff --git a/...nMain/kotlin/com/ionspin/kotlin/bignum/integer/base63/BigInteger63LinkedListArithmetic.kt b/...nMain/kotlin/com/ionspin/kotlin/bignum/integer/base63/BigInteger63LinkedListArithmetic.kt
@@ -1034,7 +1034,7 @@ internal object BigInteger63LinkedListArithmetic : BigIntegerList63Arithmetic {
     override fun parseForBase(number: String, base: Int): List<ULong> {
         var parsed = ZERO
         number.toLowerCase().forEach { char ->
-            parsed = (parsed * base.toULong()) + (char.toDigit()).toULong()
+            parsed = (parsed * base.toULong()) + (char.toDigit(base)).toULong()
         }
         return removeLeadingZeros(parsed)
     }

diff --git a/...ommonMain/kotlin/com/ionspin/kotlin/bignum/integer/base63/array/BigInteger63Arithmetic.kt b/...ommonMain/kotlin/com/ionspin/kotlin/bignum/integer/base63/array/BigInteger63Arithmetic.kt
@@ -1925,7 +1925,7 @@ internal object BigInteger63Arithmetic : BigIntegerArithmetic {
     override fun parseForBase(number: String, base: Int): ULongArray {
         var parsed = ZERO
         number.toLowerCase().forEach { char ->
-            parsed = (parsed * base.toULong()) + (char.toDigit()).toULong()
+            parsed = (parsed * base.toULong()) + (char.toDigit(base)).toULong()
         }
         return removeLeadingZeros(
             parsed

diff --git a/bignum/src/commonMain/kotlin/com/ionspin/kotlin/bignum/integer/util/DigitUtil.kt b/bignum/src/commonMain/kotlin/com/ionspin/kotlin/bignum/integer/util/DigitUtil.kt
@@ -22,8 +22,10 @@ package com.ionspin.kotlin.bignum.integer.util
  * [email protected]
  * on 18-Mar-2019
  */
-fun Char.toDigit(): Int {
-    return when (this) {
+fun Char.toDigit(base: Int = 10): Int {
+    // Check if number belongs to est used in base
+
+    val digit = when (this) {
         in '0'..'9' -> (this - 48).toInt()
         in 'a'..'z' -> this - 'a' + 10
         in 'A'..'Z' -> this - 'A' + 10
@@ -32,4 +34,8 @@ fun Char.toDigit(): Int {
         '.' -> throw NumberFormatException("Invalid digit for radix $this (Possibly a decimal value, which is not supported by BigInteger parser")
         else -> throw NumberFormatException("Invalid digit for radix $this")
     }
+    if (digit < 0 || digit >= base) {
+        throw NumberFormatException("$this is not a valid digit for number system with base $base")
+    }
+    return digit
 }
diff --git a/bignum/src/commonTest/kotlin/com/ionspin/kotlin/bignum/integer/BigIntegerReadmeTest.kt b/bignum/src/commonTest/kotlin/com/ionspin/kotlin/bignum/integer/BigIntegerReadmeTest.kt
@@ -18,6 +18,7 @@
 package com.ionspin.kotlin.bignum.integer
 
 import kotlin.test.Test
+import kotlin.test.assertFailsWith
 import kotlin.test.assertTrue
 
 /**
@@ -219,6 +220,22 @@ class BigIntegerReadmeTest {
             val expected = BigInteger.parseString("12", 10)
             bigint == expected
         }
+
+        assertFailsWith(NumberFormatException::class) {
+            val parsed = BigInteger.parseString("a", 10)
+        }
+
+        assertFailsWith(NumberFormatException::class) {
+            val parsed = BigInteger.parseString("Z", 35)
+        }
+
+        assertFailsWith(NumberFormatException::class) {
+            val parsed = BigInteger.parseString("A", 37)
+        }
+
+        assertFailsWith(NumberFormatException::class) {
+            val parsed = BigInteger.parseString("A", 1)
+        }
     }
 
     @Test