README
gosec - Golang Security Checker
Inspects source code for security problems by scanning the Go AST.

License
Licensed under the Apache License, Version 2.0 (the "License"). You may not use this file except in compliance with the License. You may obtain a copy of the License here.
Project status
Install
CI Installation
# binary will be $GOPATH/bin/gosec
curl -sfL https://raw.githubusercontent.com/securego/gosec/master/install.sh | sh -s -- -b $GOPATH/bin vX.Y.Z
# or install it into ./bin/
curl -sfL https://raw.githubusercontent.com/securego/gosec/master/install.sh | sh -s vX.Y.Z
# In alpine linux (as it does not come with curl by default)
wget -O - -q https://raw.githubusercontent.com/securego/gosec/master/install.sh | sh -s vX.Y.Z
# If you want to use the checksums provided on the "Releases" page
# then you will have to download a tar.gz file for your operating system instead of a binary file
wget https://github.com/securego/gosec/releases/download/vX.Y.Z/gosec_vX.Y.Z_OS.tar.gz
# The file will be in the current folder where you run the command
# and you can check the checksum like this
echo "<check sum from the check sum file> gosec_vX.Y.Z_OS.tar.gz" | sha256sum -c -
gosec --help
Local Installation
go get github.com/securego/gosec/cmd/gosec
Usage
Gosec can be configured to only run a subset of rules, to exclude certain file
paths, and produce reports in different formats. By default all rules will be
run against the supplied input files. To recursively scan from the current
directory you can supply ./...
as the input argument.
Available rules
- G101: Look for hard coded credentials
- G102: Bind to all interfaces
- G103: Audit the use of unsafe block
- G104: Audit errors not checked
- G106: Audit the use of ssh.InsecureIgnoreHostKey
- G107: Url provided to HTTP request as taint input
- G108: Profiling endpoint automatically exposed on /debug/pprof
- G109: Potential Integer overflow made by strconv.Atoi result conversion to int16/32
- G110: Potential DoS vulnerability via decompression bomb
- G201: SQL query construction using format string
- G202: SQL query construction using string concatenation
- G203: Use of unescaped data in HTML templates
- G204: Audit use of command execution
- G301: Poor file permissions used when creating a directory
- G302: Poor file permissions used with chmod
- G303: Creating tempfile using a predictable path
- G304: File path provided as taint input
- G305: File traversal when extracting zip archive
- G306: Poor file permissions used when writing to a new file
- G307: Deferring a method which returns an error
- G401: Detect the usage of DES, RC4, MD5 or SHA1
- G402: Look for bad TLS connection settings
- G403: Ensure minimum RSA key length of 2048 bits
- G404: Insecure random number source (rand)
- G501: Import blacklist: crypto/md5
- G502: Import blacklist: crypto/des
- G503: Import blacklist: crypto/rc4
- G504: Import blacklist: net/http/cgi
- G505: Import blacklist: crypto/sha1
Retired rules
- G105: Audit the use of math/big.Int.Exp - CVE is fixed
Selecting rules
By default, gosec will run all rules against the supplied file paths. It is however possible to select a subset of rules to run via the -include=
flag,
or to specify a set of rules to explicitly exclude using the -exclude=
flag.
# Run a specific set of rules
$ gosec -include=G101,G203,G401 ./...
# Run everything except for rule G303
$ gosec -exclude=G303 ./...
CWE Mapping
Every issue detected by gosec
is mapped to a CWE (Common Weakness Enumeration) which describes in more generic terms the vulnerability. The exact mapping can be found here.
Configuration
A number of global settings can be provided in a configuration file as follows:
{
"global": {
"nosec": "enabled",
"audit": "enabled"
}
}
nosec
: this setting will overwrite all#nosec
directives defined throughout the code baseaudit
: runs in audit mode which enables addition checks that for normal code analysis might be too nosy
# Run with a global configuration file
$ gosec -conf config.json .
Also some rules accept configuration. For instance on rule G104
, it is possible to define packages along with a list
of functions which will be skipped when auditing the not checked errors:
{
"G104": {
"io/ioutil": ["WriteFile"]
}
}
Dependencies
gosec will fetch automatically the dependencies of the code which is being analyzed when go module is turned on (e.g. GO111MODULE=on
). If this is not the case,
the dependencies need to be explicitly downloaded by running the go get -d
command before the scan.
Excluding test files and folders
gosec will ignore test files across all packages and any dependencies in your vendor directory.
The scanning of test files can be enabled with the following flag:
gosec -tests ./...
Also additional folders can be excluded as follows:
gosec -exclude-dir=rules -exclude-dir=cmd ./...
Annotating code
As with all automated detection tools, there will be cases of false positives. In cases where gosec reports a failure that has been manually verified as being safe,
it is possible to annotate the code with a #nosec
comment.
The annotation causes gosec to stop processing any further nodes within the AST so can apply to a whole block or more granularly to a single expression.
import "md5" // #nosec
func main(){
/* #nosec */
if x > y {
h := md5.New() // this will also be ignored
}
}
When a specific false positive has been identified and verified as safe, you may wish to suppress only that single rule (or a specific set of rules)
within a section of code, while continuing to scan for other problems. To do this, you can list the rule(s) to be suppressed within
the #nosec
annotation, e.g: /* #nosec G401 */
or // #nosec G201 G202 G203
In some cases you may also want to revisit places where #nosec
annotations
have been used. To run the scanner and ignore any #nosec
annotations you
can do the following:
gosec -nosec=true ./...
Build tags
gosec is able to pass your Go build tags to the analyzer. They can be provided as a comma separated list as follows:
gosec -tag debug,ignore ./...
Output formats
gosec currently supports text, json, yaml, csv, sonarqube, JUnit XML and golint output formats. By default results will be reported to stdout, but can also be written to an output file. The output format is controlled by the '-fmt' flag, and the output file is controlled by the '-out' flag as follows:
# Write output in json format to results.json
$ gosec -fmt=json -out=results.json *.go
Development
Build
make
Tests
make test
Release Build
Make sure you have installed the goreleaser tool and then you can release gosec as follows:
git tag v1.0.0
export GITHUB_TOKEN=<YOUR GITHUB TOKEN>
make release
The released version of the tool is available in the dist
folder. The build information should be displayed in the usage text.
./dist/darwin_amd64/gosec -h
gosec - Golang security checker
gosec analyzes Go source code to look for common programming mistakes that
VERSION: 1.0.0
GIT TAG: v1.0.0
BUILD DATE: 2018-04-27T12:41:38Z
Note that all released archives are also uploaded to GitHub.
Docker image
You can build the docker image as follows:
make image
You can run the gosec
tool in a container against your local Go project. You just have to mount the project
into a volume as follows:
docker run -it -v <YOUR PROJECT PATH>/<PROJECT>:/<PROJECT> securego/gosec /<PROJECT>/...
Generate TLS rule
The configuration of TLS rule can be generated from Mozilla's TLS ciphers recommendation.
First you need to install the generator tool:
go get github.com/securego/gosec/cmd/tlsconfig/...
You can invoke now the go generate
in the root of the project:
go generate ./...
This will generate the rules/tls_config.go
file which will contain the current ciphers recommendation from Mozilla.
Documentation
Overview ¶
Package gosec holds the central scanning logic used by gosec security scanner
Index ¶
- Constants
- Variables
- func ConcatString(n *ast.BinaryExpr) (string, bool)
- func ExcludedDirsRegExp(excludedDirs []string) []*regexp.Regexp
- func FindVarIdentities(n *ast.BinaryExpr, c *Context) ([]*ast.Ident, bool)
- func GetCallInfo(n ast.Node, ctx *Context) (string, string, error)
- func GetCallObject(n ast.Node, ctx *Context) (*ast.CallExpr, types.Object)
- func GetCallStringArgsValues(n ast.Node, ctx *Context) []string
- func GetChar(n ast.Node) (byte, error)
- func GetFloat(n ast.Node) (float64, error)
- func GetIdentStringValues(ident *ast.Ident) []string
- func GetImportPath(name string, ctx *Context) (string, bool)
- func GetImportedName(path string, ctx *Context) (string, bool)
- func GetInt(n ast.Node) (int64, error)
- func GetLocation(n ast.Node, ctx *Context) (string, int)
- func GetPkgAbsPath(pkgPath string) (string, error)
- func GetPkgRelativePath(path string) (string, error)
- func GetString(n ast.Node) (string, error)
- func Getenv(key, userDefault string) string
- func Gopath() []string
- func MatchCallByPackage(n ast.Node, c *Context, pkg string, names ...string) (*ast.CallExpr, bool)
- func MatchCompLit(n ast.Node, ctx *Context, required string) *ast.CompositeLit
- func PackagePaths(root string, excludes []*regexp.Regexp) ([]string, error)
- func RootPath(root string) (string, error)
- func TryResolve(n ast.Node, c *Context) bool
- type Analyzer
- func (gosec *Analyzer) AppendError(file string, err error)
- func (gosec *Analyzer) Check(pkg *packages.Package)
- func (gosec *Analyzer) Config() Config
- func (gosec *Analyzer) LoadRules(ruleDefinitions map[string]RuleBuilder)
- func (gosec *Analyzer) ParseErrors(pkg *packages.Package) error
- func (gosec *Analyzer) Process(buildTags []string, packagePaths ...string) error
- func (gosec *Analyzer) Report() ([]*Issue, *Metrics, map[string][]Error)
- func (gosec *Analyzer) Reset()
- func (gosec *Analyzer) SetConfig(conf Config)
- func (gosec *Analyzer) Visit(n ast.Node) ast.Visitor
- type CallList
- func (c CallList) Add(selector, ident string)
- func (c CallList) AddAll(selector string, idents ...string)
- func (c CallList) Contains(selector, ident string) bool
- func (c CallList) ContainsCallExpr(n ast.Node, ctx *Context) *ast.CallExpr
- func (c CallList) ContainsPkgCallExpr(n ast.Node, ctx *Context, stripVendor bool) *ast.CallExpr
- func (c CallList) ContainsPointer(selector, indent string) bool
- type Config
- func (c Config) Get(section string) (interface{}, error)
- func (c Config) GetGlobal(option GlobalOption) (string, error)
- func (c Config) IsGlobalEnabled(option GlobalOption) (bool, error)
- func (c Config) ReadFrom(r io.Reader) (int64, error)
- func (c Config) Set(section string, value interface{})
- func (c Config) SetGlobal(option GlobalOption, value string)
- func (c Config) WriteTo(w io.Writer) (int64, error)
- type Context
- type Cwe
- type Error
- type GlobalOption
- type ImportTracker
- type Issue
- type MetaData
- type Metrics
- type Rule
- type RuleBuilder
- type RuleSet
- type Score
Constants ¶
const ( // Globals are applicable to all rules and used for general // configuration settings for gosec. Globals = "global" )
const LoadMode = packages.NeedName | packages.NeedFiles | packages.NeedCompiledGoFiles | packages.NeedImports | packages.NeedTypes | packages.NeedTypesSizes | packages.NeedTypesInfo | packages.NeedSyntax
LoadMode controls the amount of details to return when loading the packages
Variables ¶
var IssueToCWE = map[string]Cwe{ "G101": GetCwe("798"), "G102": GetCwe("200"), "G103": GetCwe("242"), "G104": GetCwe("703"), "G106": GetCwe("322"), "G107": GetCwe("88"), "G109": GetCwe("190"), "G110": GetCwe("409"), "G201": GetCwe("89"), "G202": GetCwe("89"), "G203": GetCwe("79"), "G204": GetCwe("78"), "G301": GetCwe("276"), "G302": GetCwe("276"), "G303": GetCwe("377"), "G304": GetCwe("22"), "G305": GetCwe("22"), "G401": GetCwe("326"), "G402": GetCwe("295"), "G403": GetCwe("310"), "G404": GetCwe("338"), "G501": GetCwe("327"), "G502": GetCwe("327"), "G503": GetCwe("327"), "G504": GetCwe("327"), "G505": GetCwe("327"), }
IssueToCWE maps gosec rules to CWEs
Functions ¶
func ConcatString ¶
func ConcatString(n *ast.BinaryExpr) (string, bool)
ConcatString recursively concatenates strings from a binary expression
func ExcludedDirsRegExp ¶
ExcludedDirsRegExp builds the regexps for a list of excluded dirs provided as strings
func FindVarIdentities ¶
FindVarIdentities returns array of all variable identities in a given binary expression
func GetCallInfo ¶
GetCallInfo returns the package or type and name associated with a call expression.
func GetCallObject ¶
GetCallObject returns the object and call expression and associated object for a given AST node. nil, nil will be returned if the object cannot be resolved.
func GetCallStringArgsValues ¶
GetCallStringArgsValues returns the values of strings arguments if they can be resolved
func GetIdentStringValues ¶
GetIdentStringValues return the string values of an Ident if they can be resolved
func GetImportPath ¶
GetImportPath resolves the full import path of an identifier based on the imports in the current context.
func GetImportedName ¶
GetImportedName returns the name used for the package within the code. It will resolve aliases and ignores initialization only imports.
func GetLocation ¶
GetLocation returns the filename and line number of an ast.Node
func GetPkgAbsPath ¶
GetPkgAbsPath returns the Go package absolute path derived from the given path
func GetPkgRelativePath ¶
GetPkgRelativePath returns the Go relative relative path derived form the given path
func Getenv ¶
Getenv returns the values of the environment variable, otherwise returns the default if variable is not set
func MatchCallByPackage ¶
MatchCallByPackage ensures that the specified package is imported, adjusts the name for any aliases and ignores cases that are initialization only imports.
Usage:
node, matched := MatchCallByPackage(n, ctx, "math/rand", "Read")
func MatchCompLit ¶
MatchCompLit will match an ast.CompositeLit based on the supplied type
func PackagePaths ¶
PackagePaths returns a slice with all packages path at given root directory
Types ¶
type Analyzer ¶
type Analyzer struct {
// contains filtered or unexported fields
}
Analyzer object is the main object of gosec. It has methods traverse an AST and invoke the correct checking rules as on each node as required.
func NewAnalyzer ¶
NewAnalyzer builds a new analyzer.
func (*Analyzer) AppendError ¶
AppendError appends an error to the file errors
func (*Analyzer) LoadRules ¶
func (gosec *Analyzer) LoadRules(ruleDefinitions map[string]RuleBuilder)
LoadRules instantiates all the rules to be used when analyzing source packages
func (*Analyzer) ParseErrors ¶
ParseErrors parses the errors from given package
func (*Analyzer) Report ¶
Report returns the current issues discovered and the metrics about the scan
func (*Analyzer) Reset ¶
func (gosec *Analyzer) Reset()
Reset clears state such as context, issues and metrics from the configured analyzer
type CallList ¶
type CallList map[string]set
CallList is used to check for usage of specific packages and functions.
func (CallList) Contains ¶
Contains returns true if the package and function are / members of this call list.
func (CallList) ContainsCallExpr ¶
ContainsCallExpr resolves the call expression name and type, and then determines if the call exists with the call list
func (CallList) ContainsPkgCallExpr ¶
ContainsPkgCallExpr resolves the call expression name and type, and then further looks
up the package path for that type. Finally, it determines if the call exists within the call list
func (CallList) ContainsPointer ¶
ContainsPointer returns true if a pointer to the selector type or the type itself is a members of this call list.
type Config ¶
type Config map[string]interface{}
Config is used to provide configuration and customization to each of the rules.
func NewConfig ¶
func NewConfig() Config
NewConfig initializes a new configuration instance. The configuration data then needs to be loaded via c.ReadFrom(strings.NewReader("config data")) or from a *os.File.
func (Config) GetGlobal ¶
func (c Config) GetGlobal(option GlobalOption) (string, error)
GetGlobal returns value associated with global configuration option
func (Config) IsGlobalEnabled ¶
func (c Config) IsGlobalEnabled(option GlobalOption) (bool, error)
IsGlobalEnabled checks if a global option is enabled
func (Config) ReadFrom ¶
ReadFrom implements the io.ReaderFrom interface. This should be used with io.Reader to load configuration from file or from string etc.
func (Config) SetGlobal ¶
func (c Config) SetGlobal(option GlobalOption, value string)
SetGlobal associates a value with a global configuration option
type Context ¶
type Context struct { FileSet *token.FileSet Comments ast.CommentMap Info *types.Info Pkg *types.Package PkgFiles []*ast.File Root *ast.File Config Config Imports *ImportTracker Ignores []map[string]bool PassedValues map[string]interface{} }
The Context is populated with data parsed from the source code as it is scanned. It is passed through to all rule functions as they are called. Rules may use this data in conjunction withe the encountered AST node.
type GlobalOption ¶
type GlobalOption string
GlobalOption defines the name of the global options
const ( // Nosec global option for #nosec directive Nosec GlobalOption = "nosec" // Audit global option which indicates that gosec runs in audit mode Audit GlobalOption = "audit" // NoSecAlternative global option alternative for #nosec directive NoSecAlternative GlobalOption = "#nosec" )
type ImportTracker ¶
type ImportTracker struct { Imported map[string]string Aliased map[string]string InitOnly map[string]bool }
ImportTracker is used to normalize the packages that have been imported by a source file. It is able to differentiate between plain imports, aliased imports and init only imports.
func NewImportTracker ¶
func NewImportTracker() *ImportTracker
NewImportTracker creates an empty Import tracker instance
func (*ImportTracker) TrackFile ¶
func (t *ImportTracker) TrackFile(file *ast.File)
TrackFile track all the imports used by the supplied file
func (*ImportTracker) TrackImport ¶
func (t *ImportTracker) TrackImport(n ast.Node)
TrackImport tracks imports and handles the 'unsafe' import
func (*ImportTracker) TrackPackages ¶
func (t *ImportTracker) TrackPackages(pkgs ...*types.Package)
TrackPackages tracks all the imports used by the supplied packages
type Issue ¶
type Issue struct { Severity Score `json:"severity"` // issue severity (how problematic it is) Confidence Score `json:"confidence"` // issue confidence (how sure we are we found it) Cwe Cwe `json:"cwe"` // Cwe associated with RuleID RuleID string `json:"rule_id"` // Human readable explanation What string `json:"details"` // Human readable explanation File string `json:"file"` // File name we found it in Code string `json:"code"` // Impacted code line Line string `json:"line"` // Line number in file Col string `json:"column"` // Column number in line }
Issue is returned by a gosec rule if it discovers an issue with the scanned code.
type MetaData ¶
MetaData is embedded in all gosec rules. The Severity, Confidence and What message will be passed through to reported issues.
type Metrics ¶
type Metrics struct { NumFiles int `json:"files"` NumLines int `json:"lines"` NumNosec int `json:"nosec"` NumFound int `json:"found"` }
Metrics used when reporting information about a scanning run.
type RuleBuilder ¶
RuleBuilder is used to register a rule definition with the analyzer
type RuleSet ¶
A RuleSet maps lists of rules to the type of AST node they should be run on. The analyzer will only invoke rules contained in the list associated with the type of AST node it is currently visiting.
type Score ¶
type Score int
Score type used by severity and confidence values
func (Score) MarshalJSON ¶
MarshalJSON is used convert a Score object into a JSON representation