cleanup comments for nicer godocs

lang/funcs/crypto.go

@@ -1,9 +1,15 @@
 package funcs
 
 import (
+	"crypto/md5"
+	"crypto/rsa"
+	"crypto/sha1"
 	"crypto/sha256"
 	"crypto/sha512"
+	"crypto/x509"
 	"encoding/base64"
+	"encoding/hex"
+	"encoding/pem"
 	"fmt"
 
 	uuid "github.com/hashicorp/go-uuid"
@@ -25,8 +31,8 @@ var UUIDFunc = function.New(&function.Spec{
 	},
 })
 
-// Base64Sha256Func constructs a function that computes the SHA256 hash of a given string and encodes it with
+// Base64Sha256Func constructs a function that computes the SHA256 hash of a given string
-// Base64.
+// and encodes it with Base64.
 var Base64Sha256Func = function.New(&function.Spec{
 	Params: []function.Parameter{
 		{
@@ -44,8 +50,8 @@ var Base64Sha256Func = function.New(&function.Spec{
 	},
 })
 
-// Base64Sha512Func constructs a function that computes the SHA256 hash of a given string and encodes it with
+// Base64Sha512Func constructs a function that computes the SHA256 hash of a given string
-// Base64.
+// and encodes it with Base64.
 var Base64Sha512Func = function.New(&function.Spec{
 	Params: []function.Parameter{
 		{
@@ -101,6 +107,89 @@ var BcryptFunc = function.New(&function.Spec{
 	},
 })
 
+// Md5Func constructs a function that computes the MD5 hash of a given string and encodes it with hexadecimal digits.
+var Md5Func = function.New(&function.Spec{
+	Params: []function.Parameter{
+		{
+			Name: "str",
+			Type: cty.String,
+		},
+	},
+	Type: function.StaticReturnType(cty.String),
+	Impl: func(args []cty.Value, retType cty.Type) (ret cty.Value, err error) {
+		s := args[0].AsString()
+		h := md5.New()
+		h.Write([]byte(s))
+		hash := hex.EncodeToString(h.Sum(nil))
+		return cty.StringVal(hash), nil
+	},
+})
+
+// RsaDecryptFunc constructs a function that decrypts an RSA-encrypted ciphertext.
+var RsaDecryptFunc = function.New(&function.Spec{
+	Params: []function.Parameter{
+		{
+			Name: "ciphertext",
+			Type: cty.String,
+		},
+		{
+			Name: "privatekey",
+			Type: cty.String,
+		},
+	},
+	Type: function.StaticReturnType(cty.String),
+	Impl: func(args []cty.Value, retType cty.Type) (ret cty.Value, err error) {
+		s := args[0].AsString()
+		key := args[1].AsString()
+
+		b, err := base64.StdEncoding.DecodeString(s)
+		if err != nil {
+			return cty.UnknownVal(cty.String), fmt.Errorf("Failed to decode input %q: cipher text must be base64-encoded", key)
+		}
+
+		block, _ := pem.Decode([]byte(key))
+		if block == nil {
+			return cty.UnknownVal(cty.String), fmt.Errorf("Failed to read key %q: no key found", key)
+		}
+		if block.Headers["Proc-Type"] == "4,ENCRYPTED" {
+			return cty.UnknownVal(cty.String), fmt.Errorf(
+				"Failed to read key %q: password protected keys are\n"+
+					"not supported. Please decrypt the key prior to use.", key)
+		}
+
+		x509Key, err := x509.ParsePKCS1PrivateKey(block.Bytes)
+		if err != nil {
+			return cty.UnknownVal(cty.String), err
+		}
+
+		out, err := rsa.DecryptPKCS1v15(nil, x509Key, b)
+		if err != nil {
+			return cty.UnknownVal(cty.String), err
+		}
+
+		return cty.StringVal(string(out)), nil
+	},
+})
+
+// Sha1Func contructs a function that computes the SHA1 hash of a given string
+// and encodes it with hexadecimal digits.
+var Sha1Func = function.New(&function.Spec{
+	Params: []function.Parameter{
+		{
+			Name: "str",
+			Type: cty.String,
+		},
+	},
+	Type: function.StaticReturnType(cty.String),
+	Impl: func(args []cty.Value, retType cty.Type) (ret cty.Value, err error) {
+		s := args[0].AsString()
+		h := sha1.New()
+		h.Write([]byte(s))
+		hash := hex.EncodeToString(h.Sum(nil))
+		return cty.StringVal(hash), nil
+	},
+})
+
 // UUID generates and returns a Type-4 UUID in the standard hexadecimal string
 // format.
 //
@@ -111,30 +200,28 @@ func UUID() (cty.Value, error) {
 	return UUIDFunc.Call(nil)
 }
 
-// Base64sha256 computes the SHA256 hash of a given string and encodes it with
+// Base64Sha256 computes the SHA256 hash of a given string and encodes it with
 // Base64.
 //
 // The given string is first encoded as UTF-8 and then the SHA256 algorithm is applied
-// as defined in [RFC 4634](https://tools.ietf.org/html/rfc4634). The raw hash is
+// as defined in RFC 4634. The raw hash is then encoded with Base64 before returning.
-// then encoded with Base64 before returning. Terraform uses the "standard" Base64
+// Terraform uses the "standard" Base64 alphabet as defined in RFC 4648 section 4.
-// alphabet as defined in [RFC 4648 section 4](https://tools.ietf.org/html/rfc4648#section-4).
 func Base64Sha256(str cty.Value) (cty.Value, error) {
 	return Base64Sha256Func.Call([]cty.Value{str})
 }
 
-// Base64sha512 computes the SHA512 hash of a given string and encodes it with
+// Base64Sha512 computes the SHA512 hash of a given string and encodes it with
 // Base64.
 //
 // The given string is first encoded as UTF-8 and then the SHA256 algorithm is applied
-// as defined in [RFC 4634](https://tools.ietf.org/html/rfc4634). The raw hash is
+// as defined in RFC 4634. The raw hash is then encoded with Base64 before returning.
-// then encoded with Base64 before returning. Terraform uses the "standard" Base64
+// Terraform uses the "standard" Base64  alphabet as defined in RFC 4648 section 4
-// alphabet as defined in [RFC 4648 section 4](https://tools.ietf.org/html/rfc4648#section-4).
 func Base64Sha512(str cty.Value) (cty.Value, error) {
 	return Base64Sha512Func.Call([]cty.Value{str})
 }
 
 // Bcrypt computes a hash of the given string using the Blowfish cipher,
-// returning a string in the Modular Crypt Format(https://passlib.readthedocs.io/en/stable/modular_crypt_format.html)
+// returning a string in the Modular Crypt Format
 // usually expected in the shadow password file on many Unix systems.
 func Bcrypt(str cty.Value, cost ...cty.Value) (cty.Value, error) {
 	args := make([]cty.Value, len(cost)+1)
@@ -142,3 +229,19 @@ func Bcrypt(str cty.Value, cost ...cty.Value) (cty.Value, error) {
 	copy(args[1:], cost)
 	return BcryptFunc.Call(args)
 }
+
+// Md5 computes the MD5 hash of a given string and encodes it with hexadecimal digits.
+func Md5(str cty.Value) (cty.Value, error) {
+	return Md5Func.Call([]cty.Value{str})
+}
+
+// RsaDecrypt decrypts an RSA-encrypted ciphertext, returning the corresponding
+// cleartext.
+func RsaDecrypt(ciphertext, privatekey cty.Value) (cty.Value, error) {
+	return RsaDecryptFunc.Call([]cty.Value{ciphertext, privatekey})
+}
+
+// Sha1 computes the SHA1 hash of a given string and encodes it with hexadecimal digits.
+func Sha1(str cty.Value) (cty.Value, error) {
+	return Sha1Func.Call([]cty.Value{str})
+}

lang/funcs/crypto_test.go

@@ -45,11 +45,9 @@ func TestBase64Sha256(t *testing.T) {
 					t.Fatal("succeeded; want error")
 				}
 				return
-			} else {
+			} else if err != nil {
-				if err != nil {
 				t.Fatalf("unexpected error: %s", err)
 			}
-			}
 
 			if !got.RawEquals(test.Want) {
 				t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, test.Want)
@@ -83,11 +81,9 @@ func TestBase64Sha512(t *testing.T) {
 					t.Fatal("succeeded; want error")
 				}
 				return
-			} else {
+			} else if err != nil {
-				if err != nil {
 				t.Fatalf("unexpected error: %s", err)
 			}
-			}
 
 			if !got.RawEquals(test.Want) {
 				t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, test.Want)
@@ -125,3 +121,211 @@ func TestBcrypt(t *testing.T) {
 		t.Fatal("succeeded; want error")
 	}
 }
+
+func TestMd5(t *testing.T) {
+	tests := []struct {
+		String cty.Value
+		Want   cty.Value
+		Err    bool
+	}{
+		{
+			cty.StringVal("tada"),
+			cty.StringVal("ce47d07243bb6eaf5e1322c81baf9bbf"),
+			false,
+		},
+		{ // Confirm that we're not trimming any whitespaces
+			cty.StringVal(" tada "),
+			cty.StringVal("aadf191a583e53062de2d02c008141c4"),
+			false,
+		},
+		{ // We accept empty string too
+			cty.StringVal(""),
+			cty.StringVal("d41d8cd98f00b204e9800998ecf8427e"),
+			false,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(fmt.Sprintf("md5(%#v)", test.String), func(t *testing.T) {
+			got, err := Md5(test.String)
+
+			if test.Err {
+				if err == nil {
+					t.Fatal("succeeded; want error")
+				}
+				return
+			} else if err != nil {
+				t.Fatalf("unexpected error: %s", err)
+			}
+
+			if !got.RawEquals(test.Want) {
+				t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, test.Want)
+			}
+		})
+	}
+}
+
+func TestRsaDecrypt(t *testing.T) {
+	tests := []struct {
+		Ciphertext cty.Value
+		Privatekey cty.Value
+		Want       cty.Value
+		Err        bool
+	}{
+		// Base-64 encoded cipher decrypts correctly
+		{
+			cty.StringVal(CipherBase64),
+			cty.StringVal(PrivateKey),
+			cty.StringVal("message"),
+			false,
+		},
+		// Wrong key
+		{
+			cty.StringVal(CipherBase64),
+			cty.StringVal(WrongPrivateKey),
+			cty.UnknownVal(cty.String),
+			true,
+		},
+		// Bad key
+		{
+			cty.StringVal(CipherBase64),
+			cty.StringVal("bad key"),
+			cty.UnknownVal(cty.String),
+			true,
+		},
+		// Empty key
+		{
+			cty.StringVal(CipherBase64),
+			cty.StringVal(""),
+			cty.UnknownVal(cty.String),
+			true,
+		},
+		// Bad cipher
+		{
+			cty.StringVal("bad cipher"),
+			cty.StringVal(PrivateKey),
+			cty.UnknownVal(cty.String),
+			true,
+		},
+		// Empty cipher
+		{
+			cty.StringVal(""),
+			cty.StringVal(PrivateKey),
+			cty.UnknownVal(cty.String),
+			true,
+		},
+	}
+	for _, test := range tests {
+		t.Run(fmt.Sprintf("RsaDecrypt(%#v, %#v)", test.Ciphertext, test.Privatekey), func(t *testing.T) {
+			got, err := RsaDecrypt(test.Ciphertext, test.Privatekey)
+
+			if test.Err {
+				if err == nil {
+					t.Fatal("succeeded; want error")
+				}
+				return
+			} else if err != nil {
+				t.Fatalf("unexpected error: %s", err)
+			}
+
+			if !got.RawEquals(test.Want) {
+				t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, test.Want)
+			}
+		})
+	}
+}
+
+func TestSha1(t *testing.T) {
+	tests := []struct {
+		String cty.Value
+		Want   cty.Value
+		Err    bool
+	}{
+		{
+			cty.StringVal("test"),
+			cty.StringVal("a94a8fe5ccb19ba61c4c0873d391e987982fbbd3"),
+			false,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(fmt.Sprintf("sha1(%#v)", test.String), func(t *testing.T) {
+			got, err := Sha1(test.String)
+
+			if test.Err {
+				if err == nil {
+					t.Fatal("succeeded; want error")
+				}
+				return
+			} else if err != nil {
+				t.Fatalf("unexpected error: %s", err)
+			}
+
+			if !got.RawEquals(test.Want) {
+				t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, test.Want)
+			}
+		})
+	}
+}
+
+const (
+	CipherBase64 = "eczGaDhXDbOFRZGhjx2etVzWbRqWDlmq0bvNt284JHVbwCgObiuyX9uV0LSAMY707IEgMkExJqXmsB4OWKxvB7epRB9G/3+F+pcrQpODlDuL9oDUAsa65zEpYF0Wbn7Oh7nrMQncyUPpyr9WUlALl0gRWytOA23S+y5joa4M34KFpawFgoqTu/2EEH4Xl1zo+0fy73fEto+nfkUY+meuyGZ1nUx/+DljP7ZqxHBFSlLODmtuTMdswUbHbXbWneW51D7Jm7xB8nSdiA2JQNK5+Sg5x8aNfgvFTt/m2w2+qpsyFa5Wjeu6fZmXSl840CA07aXbk9vN4I81WmJyblD/ZA=="
+	PrivateKey   = `
+-----BEGIN RSA PRIVATE KEY-----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+-----END RSA PRIVATE KEY-----
+`
+	WrongPrivateKey = `
+-----BEGIN RSA PRIVATE KEY-----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+-----END RSA PRIVATE KEY-----
+`
+)

lang/funcs/datetime.go

@@ -46,19 +46,17 @@ var TimeAddFunc = function.New(&function.Spec{
 // Timestamp returns a string representation of the current date and time.
 //
 // In the Terraform language, timestamps are conventionally represented as
-// strings using [RFC 3339](https://tools.ietf.org/html/rfc3339)
+// strings using RFC 3339 "Date and Time format" syntax, and so timestamp
-// "Date and Time format" syntax, and so `timestamp` returns a string
+// returns a string in this format.
-// in this format.
 func Timestamp() (cty.Value, error) {
 	return TimestampFunc.Call([]cty.Value{})
 }
 
-// Timeadd adds a duration to a timestamp, returning a new timestamp.
+// TimeAdd adds a duration to a timestamp, returning a new timestamp.
 //
 // In the Terraform language, timestamps are conventionally represented as
-// strings using [RFC 3339](https://tools.ietf.org/html/rfc3339)
+// strings using RFC 3339 "Date and Time format" syntax. Timeadd requires
-// "Date and Time format" syntax. `timeadd` requires the `timestamp` argument
+// the timestamp argument to be a string conforming to this syntax.
-// to be a string conforming to this syntax.
 //
 // `duration` is a string representation of a time difference, consisting of
 // sequences of number and unit pairs, like `"1.5h"` or `1h30m`. The accepted

lang/funcs/datetime_test.go

@@ -73,11 +73,9 @@ func TestTimeadd(t *testing.T) {
 					t.Fatal("succeeded; want error")
 				}
 				return
-			} else {
+			} else if err != nil {
-				if err != nil {
 				t.Fatalf("unexpected error: %s", err)
 			}
-			}
 
 			if !got.RawEquals(test.Want) {
 				t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, test.Want)

lang/funcs/encoding.go

@@ -89,8 +89,7 @@ var URLEncodeFunc = function.New(&function.Spec{
 
 // Base64Decode decodes a string containing a base64 sequence.
 //
-// Terraform uses the "standard" Base64 alphabet as defined in
+// Terraform uses the "standard" Base64 alphabet as defined in RFC 4648 section 4.
-// [RFC 4648 section 4](https://tools.ietf.org/html/rfc4648#section-4).
 //
 // Strings in the Terraform language are sequences of unicode characters rather
 // than bytes, so this function will also interpret the resulting bytes as
@@ -102,8 +101,7 @@ func Base64Decode(str cty.Value) (cty.Value, error) {
 
 // Base64Encode applies Base64 encoding to a string.
 //
-// Terraform uses the "standard" Base64 alphabet as defined in
+// Terraform uses the "standard" Base64 alphabet as defined in RFC 4648 section 4.
-// [RFC 4648 section 4](https://tools.ietf.org/html/rfc4648#section-4).
 //
 // Strings in the Terraform language are sequences of unicode characters rather
 // than bytes, so this function will first encode the characters from the string
@@ -112,11 +110,11 @@ func Base64Encode(str cty.Value) (cty.Value, error) {
 	return Base64EncodeFunc.Call([]cty.Value{str})
 }
 
-// Base64gzip compresses a string with gzip and then encodes the result in
+// Base64Gzip compresses a string with gzip and then encodes the result in
 // Base64 encoding.
 //
-// Terraform uses the "standard" Base64 alphabet as defined in
+// Terraform uses the "standard" Base64 alphabet as defined in RFC 4648 section 4.
-// [RFC 4648 section 4](https://tools.ietf.org/html/rfc4648#section-4)
+//
 // Strings in the Terraform language are sequences of unicode characters rather
 // than bytes, so this function will first encode the characters from the string
 // as UTF-8, then apply gzip compression, and then finally apply Base64 encoding.
@@ -124,12 +122,11 @@ func Base64Gzip(str cty.Value) (cty.Value, error) {
 	return Base64GzipFunc.Call([]cty.Value{str})
 }
 
-// UrlEncode applies URL encoding to a given string.
+// URLEncode applies URL encoding to a given string.
 //
 // This function identifies characters in the given string that would have a
 // special meaning when included as a query string argument in a URL and
-// escapes them using
+// escapes them using RFC 3986 "percent encoding".
-// [RFC 3986 "percent encoding"](https://tools.ietf.org/html/rfc3986#section-2.1).
 //
 // If the given string contains non-ASCII characters, these are first encoded as
 // UTF-8 and then percent encoding is applied separately to each UTF-8 byte.

lang/funcs/encoding_test.go

@@ -34,11 +34,9 @@ func TestBase64Decode(t *testing.T) {
 					t.Fatal("succeeded; want error")
 				}
 				return
-			} else {
+			} else if err != nil {
-				if err != nil {
 				t.Fatalf("unexpected error: %s", err)
 			}
-			}
 
 			if !got.RawEquals(test.Want) {
 				t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, test.Want)
@@ -69,11 +67,9 @@ func TestBase64Encode(t *testing.T) {
 					t.Fatal("succeeded; want error")
 				}
 				return
-			} else {
+			} else if err != nil {
-				if err != nil {
 				t.Fatalf("unexpected error: %s", err)
 			}
-			}
 
 			if !got.RawEquals(test.Want) {
 				t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, test.Want)
@@ -104,11 +100,9 @@ func TestBase64Gzip(t *testing.T) {
 					t.Fatal("succeeded; want error")
 				}
 				return
-			} else {
+			} else if err != nil {
-				if err != nil {
 				t.Fatalf("unexpected error: %s", err)
 			}
-			}
 
 			if !got.RawEquals(test.Want) {
 				t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, test.Want)
@@ -154,11 +148,9 @@ func TestURLEncode(t *testing.T) {
 					t.Fatal("succeeded; want error")
 				}
 				return
-			} else {
+			} else if err != nil {
-				if err != nil {
 				t.Fatalf("unexpected error: %s", err)
 			}
-			}
 
 			if !got.RawEquals(test.Want) {
 				t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, test.Want)

lang/funcs/filesystem.go

@@ -63,7 +63,8 @@ func MakeFileFunc(baseDir string, encBase64 bool) function.Function {
 	})
 }
 
-// BasenameFunc constructs a function that takes a string containing a filesystem path and removes all except the last portion from it.
+// BasenameFunc constructs a function that takes a string containing a filesystem path
+// and removes all except the last portion from it.
 var BasenameFunc = function.New(&function.Spec{
 	Params: []function.Parameter{
 		{
@@ -77,7 +78,8 @@ var BasenameFunc = function.New(&function.Spec{
 	},
 })
 
-// DirnameFunc constructs a function that takes a string containing a filesystem path and removes the last portion from it.
+// DirnameFunc constructs a function that takes a string containing a filesystem path
+// and removes the last portion from it.
 var DirnameFunc = function.New(&function.Spec{
 	Params: []function.Parameter{
 		{

lang/funcs/filesystem_test.go

@@ -41,11 +41,9 @@ func TestFile(t *testing.T) {
 					t.Fatal("succeeded; want error")
 				}
 				return
-			} else {
+			} else if err != nil {
-				if err != nil {
 				t.Fatalf("unexpected error: %s", err)
 			}
-			}
 
 			if !got.RawEquals(test.Want) {
 				t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, test.Want)
@@ -86,11 +84,9 @@ func TestFileBase64(t *testing.T) {
 					t.Fatal("succeeded; want error")
 				}
 				return
-			} else {
+			} else if err != nil {
-				if err != nil {
 				t.Fatalf("unexpected error: %s", err)
 			}
-			}
 
 			if !got.RawEquals(test.Want) {
 				t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, test.Want)
@@ -131,11 +127,9 @@ func TestBasename(t *testing.T) {
 					t.Fatal("succeeded; want error")
 				}
 				return
-			} else {
+			} else if err != nil {
-				if err != nil {
 				t.Fatalf("unexpected error: %s", err)
 			}
-			}
 
 			if !got.RawEquals(test.Want) {
 				t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, test.Want)
@@ -181,11 +175,9 @@ func TestDirname(t *testing.T) {
 					t.Fatal("succeeded; want error")
 				}
 				return
-			} else {
+			} else if err != nil {
-				if err != nil {
 				t.Fatalf("unexpected error: %s", err)
 			}
-			}
 
 			if !got.RawEquals(test.Want) {
 				t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, test.Want)
@@ -236,11 +228,9 @@ func TestPathExpand(t *testing.T) {
 					t.Fatal("succeeded; want error")
 				}
 				return
-			} else {
+			} else if err != nil {
-				if err != nil {
 				t.Fatalf("unexpected error: %s", err)
 			}
-			}
 
 			if !got.RawEquals(test.Want) {
 				t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, test.Want)

lang/functions.go

@@ -11,6 +11,7 @@ import (
 )
 
 var impureFunctions = []string{
+	"bcrypt",
 	"timestamp",
 	"uuid",
 }
@@ -71,13 +72,13 @@ func (s *Scope) Functions() map[string]function.Function {
 			"lower":        stdlib.LowerFunc,
 			"map":          unimplFunc, // TODO
 			"max":          stdlib.MaxFunc,
-			"md5":          unimplFunc, // TODO
+			"md5":          funcs.Md5Func,
 			"merge":        unimplFunc, // TODO
 			"min":          stdlib.MinFunc,
 			"pathexpand":   funcs.PathExpandFunc,
 			"pow":          unimplFunc, // TODO
 			"replace":      unimplFunc, // TODO
-			"rsadecrypt":   unimplFunc, // TODO
+			"rsadecrypt":   funcs.RsaDecryptFunc,
 			"sha1":         unimplFunc, // TODO
 			"sha256":       unimplFunc, // TODO
 			"sha512":       unimplFunc, // TODO
@@ -92,7 +93,7 @@ func (s *Scope) Functions() map[string]function.Function {
 			"transpose":    unimplFunc, // TODO
 			"trimspace":    unimplFunc, // TODO
 			"upper":        stdlib.UpperFunc,
-			"urlencode":    funcs.UrlEncodeFunc,
+			"urlencode":    funcs.URLEncodeFunc,
 			"uuid":         funcs.UUIDFunc,
 			"values":       unimplFunc, // TODO
 			"zipmap":       unimplFunc, // TODO