sdk

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cosmos-sdk rules

These rules are targeted for the Cosmos-sdk to catch common mistakes that could be devasting.

Table of contents

• Unsafe imports
• strconv unsigned integers cast to signed integers overflow
• Non deterministic map iteration

Unsafe imports

Imports like unsafe, runtime and math/rand are potential sources of non-determinism and hence they are flagged when in code.

strconv unsigned integers cast to signed integers overflow

Parsing signed integers consumes one bit less than their unsigned counterparts. The usage of strconv.ParseUint to parse a signed integer out of a string returns an unsigned 64-bit integer uint64. This uint64 if cast with the wrong constant bitsize is now flagged, for example the following

    u64, err := strconv.ParseUint(str, 10, 64)
    if err != nil {
        panic(err)
    }
    i64 := int64(u64)

which ideally should have been

    u64, err := strconv.ParseUint(str, 10, 63)
    if err != nil {
        panic(err)
    }
    i64 := int64(u64)

Non deterministic map iteration

In Go, iterating over maps is intentionally non-deterministic as the runtime defines. Unfortunately for us, in the Cosmos-SDK, we encountered an issue with non-deterministic upgrades in Issue cosmos-sdk#10188 PR cosmos-sdk#10189 that resulted from exactly this non-deterministic iteration. To ensure determinism, we only permit an iteration to retrieve the map keys and then those keys can then be sorted, so instead of

for k, v := range m {
    // Do something with key and value.
    _, _ = k, v
}

the requested pattern is instead

keys := make([]string, 0, len(m))
for k := range m {
    keys = append(keys, k)
}
sort.Strings(keys)

for _, key := range keys {
    // Use the value.
    _ = m[key]
}

Documentation

Index

• func NewBlocklistedImports(id string, conf gosec.Config, blocklist map[string]string) (gosec.Rule, []ast.Node)
• func NewErrorNotPropagated(id string, conf gosec.Config) (gosec.Rule, []ast.Node)
• func NewIntegerCast(id string, conf gosec.Config) (gosec.Rule, []ast.Node)
• func NewMapRangingCheck(id string, config gosec.Config) (rule gosec.Rule, nodes []ast.Node)
• func NewStrconvIntBitSizeOverflow(id string, config gosec.Config) (rule gosec.Rule, nodes []ast.Node)
• func NewUnsafeImport(id string, conf gosec.Config) (gosec.Rule, []ast.Node)

Functions

func NewBlocklistedImports

func NewBlocklistedImports(id string, conf gosec.Config, blocklist map[string]string) (gosec.Rule, []ast.Node)

NewBlocklistedImports reports when a blocklisted import is being used. Typically when a deprecated technology is being used.

func NewErrorNotPropagated

func NewErrorNotPropagated(id string, conf gosec.Config) (gosec.Rule, []ast.Node)

NewErrorNotPropagated detects if a returned error is not propagated up the stack.

func NewIntegerCast

func NewIntegerCast(id string, conf gosec.Config) (gosec.Rule, []ast.Node)

NewIntegerCast detects if there is potential Integer OverFlow

func NewMapRangingCheck

func NewMapRangingCheck(id string, config gosec.Config) (rule gosec.Rule, nodes []ast.Node)

NewMapRangingCheck returns an error if a map is being iterated over in a for loop outside of the context of keys being retrieved for sorting, or the delete map clearing idiom.

func NewStrconvIntBitSizeOverflow

func NewStrconvIntBitSizeOverflow(id string, config gosec.Config) (rule gosec.Rule, nodes []ast.Node)

NewStrconvIntBitSizeOverflow returns an error if a constant bitSize is used for a cast signed value that was retrieved from strconv.ParseUint.

func NewUnsafeImport

func NewUnsafeImport(id string, conf gosec.Config) (gosec.Rule, []ast.Node)

NewUnsafeImport fails if any of "unsafe", "reflect", "crypto/rand", "math/rand" are imported.