1 files changed, 158 insertions, 4 deletions

diff --git a/src/test/fuzz/string.cpp b/src/test/fuzz/string.cpp
index 93b4948a2f..ca57af25c4 100644
--- a/src/test/fuzz/string.cpp
+++ b/src/test/fuzz/string.cpp
@@ -5,6 +5,7 @@
 #include <blockfilter.h>
 #include <clientversion.h>
 #include <logging.h>
+#include <netaddress.h>
 #include <netbase.h>
 #include <outputtype.h>
 #include <rpc/client.h>
@@ -30,9 +31,105 @@
 #include <version.h>
 
 #include <cstdint>
+#include <cstdlib>
 #include <string>
 #include <vector>
 
+namespace {
+bool LegacyParsePrechecks(const std::string& str)
+{
+    if (str.empty()) // No empty string allowed
+        return false;
+    if (str.size() >= 1 && (IsSpace(str[0]) || IsSpace(str[str.size() - 1]))) // No padding allowed
+        return false;
+    if (!ValidAsCString(str)) // No embedded NUL characters allowed
+        return false;
+    return true;
+}
+
+bool LegacyParseInt32(const std::string& str, int32_t* out)
+{
+    if (!LegacyParsePrechecks(str))
+        return false;
+    char* endp = nullptr;
+    errno = 0; // strtol will not set errno if valid
+    long int n = strtol(str.c_str(), &endp, 10);
+    if (out) *out = (int32_t)n;
+    // Note that strtol returns a *long int*, so even if strtol doesn't report an over/underflow
+    // we still have to check that the returned value is within the range of an *int32_t*. On 64-bit
+    // platforms the size of these types may be different.
+    return endp && *endp == 0 && !errno &&
+           n >= std::numeric_limits<int32_t>::min() &&
+           n <= std::numeric_limits<int32_t>::max();
+}
+
+bool LegacyParseInt64(const std::string& str, int64_t* out)
+{
+    if (!LegacyParsePrechecks(str))
+        return false;
+    char* endp = nullptr;
+    errno = 0; // strtoll will not set errno if valid
+    long long int n = strtoll(str.c_str(), &endp, 10);
+    if (out) *out = (int64_t)n;
+    // Note that strtoll returns a *long long int*, so even if strtol doesn't report an over/underflow
+    // we still have to check that the returned value is within the range of an *int64_t*.
+    return endp && *endp == 0 && !errno &&
+           n >= std::numeric_limits<int64_t>::min() &&
+           n <= std::numeric_limits<int64_t>::max();
+}
+
+bool LegacyParseUInt32(const std::string& str, uint32_t* out)
+{
+    if (!LegacyParsePrechecks(str))
+        return false;
+    if (str.size() >= 1 && str[0] == '-') // Reject negative values, unfortunately strtoul accepts these by default if they fit in the range
+        return false;
+    char* endp = nullptr;
+    errno = 0; // strtoul will not set errno if valid
+    unsigned long int n = strtoul(str.c_str(), &endp, 10);
+    if (out) *out = (uint32_t)n;
+    // Note that strtoul returns a *unsigned long int*, so even if it doesn't report an over/underflow
+    // we still have to check that the returned value is within the range of an *uint32_t*. On 64-bit
+    // platforms the size of these types may be different.
+    return endp && *endp == 0 && !errno &&
+           n <= std::numeric_limits<uint32_t>::max();
+}
+
+bool LegacyParseUInt8(const std::string& str, uint8_t* out)
+{
+    uint32_t u32;
+    if (!LegacyParseUInt32(str, &u32) || u32 > std::numeric_limits<uint8_t>::max()) {
+        return false;
+    }
+    if (out != nullptr) {
+        *out = static_cast<uint8_t>(u32);
+    }
+    return true;
+}
+
+bool LegacyParseUInt64(const std::string& str, uint64_t* out)
+{
+    if (!LegacyParsePrechecks(str))
+        return false;
+    if (str.size() >= 1 && str[0] == '-') // Reject negative values, unfortunately strtoull accepts these by default if they fit in the range
+        return false;
+    char* endp = nullptr;
+    errno = 0; // strtoull will not set errno if valid
+    unsigned long long int n = strtoull(str.c_str(), &endp, 10);
+    if (out) *out = (uint64_t)n;
+    // Note that strtoull returns a *unsigned long long int*, so even if it doesn't report an over/underflow
+    // we still have to check that the returned value is within the range of an *uint64_t*.
+    return endp && *endp == 0 && !errno &&
+           n <= std::numeric_limits<uint64_t>::max();
+}
+
+// For backwards compatibility checking.
+int64_t atoi64_legacy(const std::string& str)
+{
+    return strtoll(str.c_str(), nullptr, 10);
+}
+}; // namespace
+
 FUZZ_TARGET(string)
 {
     FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
@@ -48,7 +145,8 @@ FUZZ_TARGET(string)
     (void)CopyrightHolders(random_string_1);
     FeeEstimateMode fee_estimate_mode;
     (void)FeeModeFromString(random_string_1, fee_estimate_mode);
-    (void)FormatParagraph(random_string_1, fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, 1000), fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, 1000));
+    const auto width{fuzzed_data_provider.ConsumeIntegralInRange<size_t>(1, 1000)};
+    (void)FormatParagraph(random_string_1, width, fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, width));
     (void)FormatSubVersion(random_string_1, fuzzed_data_provider.ConsumeIntegral<int>(), random_string_vector);
     (void)GetDescriptorChecksum(random_string_1);
     (void)HelpExampleCli(random_string_1, random_string_2);
@@ -65,8 +163,7 @@ FUZZ_TARGET(string)
         (void)ParseNonRFCJSONValue(random_string_1);
     } catch (const std::runtime_error&) {
     }
-    OutputType output_type;
-    (void)ParseOutputType(random_string_1, output_type);
+    (void)ParseOutputType(random_string_1);
     (void)RemovePrefix(random_string_1, random_string_2);
     (void)ResolveErrMsg(random_string_1, random_string_2);
     try {
@@ -82,7 +179,7 @@ FUZZ_TARGET(string)
 #ifndef WIN32
     (void)ShellEscape(random_string_1);
 #endif // WIN32
-    int port_out;
+    uint16_t port_out;
     std::string host_out;
     SplitHostPort(random_string_1, port_out, host_out);
     (void)TimingResistantEqual(random_string_1, random_string_2);
@@ -133,4 +230,61 @@ FUZZ_TARGET(string)
         const bilingual_str bs2{random_string_2, random_string_1};
         (void)(bs1 + bs2);
     }
+    {
+        int32_t i32;
+        int64_t i64;
+        uint32_t u32;
+        uint64_t u64;
+        uint8_t u8;
+        const bool ok_i32 = ParseInt32(random_string_1, &i32);
+        const bool ok_i64 = ParseInt64(random_string_1, &i64);
+        const bool ok_u32 = ParseUInt32(random_string_1, &u32);
+        const bool ok_u64 = ParseUInt64(random_string_1, &u64);
+        const bool ok_u8 = ParseUInt8(random_string_1, &u8);
+
+        int32_t i32_legacy;
+        int64_t i64_legacy;
+        uint32_t u32_legacy;
+        uint64_t u64_legacy;
+        uint8_t u8_legacy;
+        const bool ok_i32_legacy = LegacyParseInt32(random_string_1, &i32_legacy);
+        const bool ok_i64_legacy = LegacyParseInt64(random_string_1, &i64_legacy);
+        const bool ok_u32_legacy = LegacyParseUInt32(random_string_1, &u32_legacy);
+        const bool ok_u64_legacy = LegacyParseUInt64(random_string_1, &u64_legacy);
+        const bool ok_u8_legacy = LegacyParseUInt8(random_string_1, &u8_legacy);
+
+        assert(ok_i32 == ok_i32_legacy);
+        assert(ok_i64 == ok_i64_legacy);
+        assert(ok_u32 == ok_u32_legacy);
+        assert(ok_u64 == ok_u64_legacy);
+        assert(ok_u8 == ok_u8_legacy);
+
+        if (ok_i32) {
+            assert(i32 == i32_legacy);
+        }
+        if (ok_i64) {
+            assert(i64 == i64_legacy);
+        }
+        if (ok_u32) {
+            assert(u32 == u32_legacy);
+        }
+        if (ok_u64) {
+            assert(u64 == u64_legacy);
+        }
+        if (ok_u8) {
+            assert(u8 == u8_legacy);
+        }
+    }
+
+    {
+        const int locale_independent_atoi_result = LocaleIndependentAtoi<int>(random_string_1);
+        const int64_t atoi64_result = atoi64_legacy(random_string_1);
+        assert(locale_independent_atoi_result == std::clamp<int64_t>(atoi64_result, std::numeric_limits<int>::min(), std::numeric_limits<int>::max()));
+    }
+
+    {
+        const int64_t atoi64_result = atoi64_legacy(random_string_1);
+        const int64_t locale_independent_atoi_result = LocaleIndependentAtoi<int64_t>(random_string_1);
+        assert(atoi64_result == locale_independent_atoi_result);
+    }
 }