commit 5972bb3a88d9afbe95fa07ce2033a2579a34bbab Author: Andreas Schulte Date: Sat Nov 4 01:44:04 2023 +0100 initial commit diff --git a/LICENSE b/LICENSE new file mode 100644 index 0000000..f288702 --- /dev/null +++ b/LICENSE @@ -0,0 +1,674 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. By contrast, +the GNU General Public License is intended to guarantee your freedom to +share and change all versions of a program--to make sure it remains free +software for all its users. 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If not, see . + +Also add information on how to contact you by electronic and paper mail. + + If the program does terminal interaction, make it output a short +notice like this when it starts in an interactive mode: + + Copyright (C) + This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, your program's commands +might be different; for a GUI interface, you would use an "about box". + + You should also get your employer (if you work as a programmer) or school, +if any, to sign a "copyright disclaimer" for the program, if necessary. +For more information on this, and how to apply and follow the GNU GPL, see +. + + The GNU General Public License does not permit incorporating your program +into proprietary programs. If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +. diff --git a/README.md b/README.md new file mode 100644 index 0000000..c1d0c57 --- /dev/null +++ b/README.md @@ -0,0 +1,64 @@ +# PFUG + +PFUG (**P**ermissions **F**or **U**sers & **G**roups) is a lightweight framework for the implementation of users, groups and their permissions. +To keep the footprint small, only the most basic elements are implemented. However, the most important requirements can be met. +[Argon2id](https://github.com/p-h-c/phc-winner-argon2) is used as the password hashing method, while a unique 32-byte salt is generated for each user. + +## Example + +```go +package main + +import ( + "errors" + "fmt" + + "git.0x0001f346.de/andreas/pfug" +) + +var allGroups map[string]pfug.Group = map[string]pfug.Group{ + "mastersOfSecrets": pfug.CreateGroup("mastersOfSecrets"), + "ordinaryPeople": pfug.CreateGroup("ordinaryPeople"), +} + +var accessToSecrets pfug.Permission = pfug.CreatePermission("accessToSecrets") + +func getSecret(user pfug.User) string { + for _, group := range allGroups { + if !group.HasUserAsMember(user) { + continue + } + + if !group.HasPermission(accessToSecrets) { + continue + } + + return "Epstein didn't kill himself" + } + + return "Mind your own business" +} + +func login(u pfug.User, password string) error { + if !u.IsUsingThisPassword(password) { + return errors.New("wrong password") + } + + // login + + return nil +} + +func main() { + john := pfug.CreateUser("johndoe", "john.doe@example.com", "password123") + jane := pfug.CreateUser("janedoe", "jane.doe@example.com", "asdfasdf") + + allGroups["mastersOfSecrets"], _ = allGroups["mastersOfSecrets"].AddMember(john) + allGroups["mastersOfSecrets"], _ = allGroups["mastersOfSecrets"].AddPermission(accessToSecrets) + allGroups["ordinaryPeople"], _ = allGroups["ordinaryPeople"].AddMember(john) + + fmt.Println(getSecret(john)) // "Epstein didn't kill himself" + fmt.Println(getSecret(jane)) // "Mind your own business" + fmt.Println(login(john, "123456")) // "wrong password" +} +``` \ No newline at end of file diff --git a/go.mod b/go.mod new file mode 100644 index 0000000..1b3fd19 --- /dev/null +++ b/go.mod @@ -0,0 +1,3 @@ +module git.0x0001f346.de/andreas/pfug + +go 1.21.2 diff --git a/hashing.go b/hashing.go new file mode 100644 index 0000000..8f6f7fe --- /dev/null +++ b/hashing.go @@ -0,0 +1,25 @@ +package pfug + +import ( + "encoding/base64" + + "golang.org/x/crypto/argon2" +) + +func generatePasswordHash(password string, salt string) string { + const time uint32 = 4 + const threads uint8 = 4 + const memory uint32 = 64 * 1024 + const keyLen uint32 = 32 + + dk := argon2.IDKey( + []byte(password), + []byte(salt), + time, + memory, + threads, + keyLen, + ) + + return base64.StdEncoding.EncodeToString(dk) +} diff --git a/hashing_test.go b/hashing_test.go new file mode 100644 index 0000000..83c018a --- /dev/null +++ b/hashing_test.go @@ -0,0 +1,27 @@ +package pfug + +import "testing" + +func TestGeneratePasswordHash(t *testing.T) { + salt := "deinemudda" + + data := map[string]string{ + "Password": "cGKb1Be4yuzMd7a9QvT44S6L2BGhITO+aPr/+UFGGPo=", + "123456": "bjk1U38vPhtzK8qYPiXZjt5fC+TL54abusiFWrS0wZ4=", + "123456789": "965RL3Lgmg937xr5cQS/hUCgGUFnefK+aDo9njkiB8Y=", + "12345678": "xfjWifoI42EcgTlEgT3f77PEaCKFVSt28xdRU7X+vqE=", + "1234567": "CIJ2+YHX+GHMGH5lUCNFh98RfvCJvIp5qYbRjjgwsEI=", + "Password1": "3KcQBn4On5Y7w6czkGqER0NCiaYaizTbKCFs2PnvJIo=", + "12345": "etxQ0tUR8o54IORWZghoWm+d6tUr5hWiXBzy6Jq6D1U=", + "1234567890": "NTlWzKkkfmNU7sWw4gFg+kxHNaOXdsvpV58eHog+t7I=", + "1234": "nPvFpMaXCkQmr2+mn79wKaqi7eSifngm16D65xeil6Q=", + "Qwerty123": "kifb3o+E7CZLA0rDtR0Vyv5jU5LtScyR+OeFB2mqeMw=", + } + + for d, expectedResult := range data { + result := generatePasswordHash(d, salt) + if result != expectedResult { + t.Errorf("\ngot: %q\nwanted: %q\nfor: %q", result, expectedResult, d) + } + } +} diff --git a/models.go b/models.go new file mode 100644 index 0000000..2bc016e --- /dev/null +++ b/models.go @@ -0,0 +1,85 @@ +package pfug + +import ( + "errors" + + "git.0x0001f346.de/andreas/utils" +) + +type User struct { + UUID string + Username string + Salt string + PasswordHash string + Mail string + FirstName string + LastName string +} + +type Group struct { + UUID string + Name string + Members map[string]bool + Permissions map[string]bool +} + +type Permission struct { + UUID string + Name string +} + +func (u User) ChangePassword(oldPassword string, newPassword string) (User, error) { + if !u.IsUsingThisPassword(oldPassword) { + return u, errors.New("wrong password") + } + + u.PasswordHash = generatePasswordHash(newPassword, u.Salt) + + return u, nil +} + +func (u User) IsMemberOfGroup(g Group) bool { + return g.Members[u.UUID] +} + +func (u User) IsUsingThisPassword(password string) bool { + return generatePasswordHash(password, u.Salt) == u.PasswordHash +} + +func (g Group) AddMember(u User) (Group, error) { + if !utils.IsValidUUID(u.UUID) { + return g, errors.New("unvalid UUID") + } + + g.Members[u.UUID] = true + + return g, nil +} + +func (g Group) AddPermission(p Permission) (Group, error) { + if !utils.IsValidUUID(p.UUID) { + return g, errors.New("unvalid UUID") + } + + g.Permissions[p.UUID] = true + + return g, nil +} + +func (g Group) HasUserAsMember(u User) bool { + return g.Members[u.UUID] +} + +func (g Group) HasPermission(p Permission) bool { + return g.Permissions[p.UUID] +} + +func (g Group) RemoveMember(u User) Group { + delete(g.Members, u.UUID) + return g +} + +func (g Group) RemovePermission(p Permission) Group { + delete(g.Permissions, p.UUID) + return g +} diff --git a/models_test.go b/models_test.go new file mode 100644 index 0000000..5d4c6f3 --- /dev/null +++ b/models_test.go @@ -0,0 +1,172 @@ +package pfug + +import ( + "encoding/json" + "errors" + "fmt" + "testing" +) + +func TestUserChangePassword(t *testing.T) { + firstPassword := "123456" + secondPassword := "123456789" + + user := CreateUser("johndoe", "", firstPassword) + + if !user.IsUsingThisPassword(firstPassword) { + t.Errorf("\ngot: %t\nwanted: %t\nfor: %q", false, true, firstPassword) + } + + if user.IsUsingThisPassword(secondPassword) { + t.Errorf("\ngot: %t\nwanted: %t\nfor: %q", true, false, secondPassword) + } + + user, err := user.ChangePassword(secondPassword, firstPassword) + if err == nil { + t.Errorf("\ngot: %v\nwanted: %v", err, errors.New("wrong password")) + } + + if !user.IsUsingThisPassword(firstPassword) { + t.Errorf("\ngot: %t\nwanted: %t\nfor: %q", false, true, firstPassword) + } + + if user.IsUsingThisPassword(secondPassword) { + t.Errorf("\ngot: %t\nwanted: %t\nfor: %q", true, false, secondPassword) + } + + user, err = user.ChangePassword(firstPassword, secondPassword) + if err != nil { + t.Errorf("\ngot: %v\nwanted: %v", err, nil) + } + + if user.IsUsingThisPassword(firstPassword) { + t.Errorf("\ngot: %t\nwanted: %t\nfor: %q", true, false, firstPassword) + } + + if !user.IsUsingThisPassword(secondPassword) { + t.Errorf("\ngot: %t\nwanted: %t\nfor: %q", false, true, secondPassword) + } +} + +func TestUserIsUsingThisPassword(t *testing.T) { + user := CreateUser("johndoe", "", "123456") + + data := map[string]bool{ + "": false, + " ": false, + "12345": false, + "123456": true, + "1234567": false, + } + + for d, expectedResult := range data { + result := user.IsUsingThisPassword(d) + if result != expectedResult { + t.Errorf("\ngot: %t\nwanted: %t\nfor: %q", result, expectedResult, d) + } + } +} + +func TestGroupAddMember(t *testing.T) { + user := CreateUser("johndoe", "", "123456") + group := CreateGroup("mastersOfSecrets") + + group, err := group.AddMember(user) + if err != nil { + t.Errorf("\ngot: %v\nwanted: %v", err, nil) + } + + members, _ := json.Marshal(group.Members) + result := string(members) + expectedResult := fmt.Sprintf("{\"%s\":true}", user.UUID) + if result != expectedResult { + t.Errorf("\ngot: %v\nwanted: %v", result, expectedResult) + } +} + +func TestGroupRemoveMember(t *testing.T) { + user := CreateUser("johndoe", "", "123456") + group, _ := CreateGroup("mastersOfSecrets").AddMember(user) + + group = group.RemoveMember(user) + + members, _ := json.Marshal(group.Members) + result := string(members) + expectedResult := "{}" + if result != expectedResult { + t.Errorf("\ngot: %v\nwanted: %v", result, expectedResult) + } +} + +func TestUserIsMemberOfGroup(t *testing.T) { + user := CreateUser("johndoe", "", "123456") + user2 := CreateUser("janedoe", "", "abc123") + group, _ := CreateGroup("mastersOfSecrets").AddMember(user) + + if !user.IsMemberOfGroup(group) { + t.Errorf("\ngot: %t\nwanted: %t", false, true) + } + + if user2.IsMemberOfGroup(group) { + t.Errorf("\ngot: %t\nwanted: %t", true, false) + } +} + +func TestGroupHasUserAsMember(t *testing.T) { + user := CreateUser("johndoe", "", "123456") + user2 := CreateUser("janedoe", "", "abc123") + group, _ := CreateGroup("mastersOfSecrets").AddMember(user) + + if !group.HasUserAsMember(user) { + t.Errorf("\ngot: %t\nwanted: %t", false, true) + } + + if group.HasUserAsMember(user2) { + t.Errorf("\ngot: %t\nwanted: %t", true, false) + } +} + +func TestGroupAddPermission(t *testing.T) { + permission := CreatePermission("accessToSecrets") + group := CreateGroup("mastersOfSecrets") + + group, err := group.AddPermission(permission) + if err != nil { + t.Errorf("\ngot: %v\nwanted: %v", err, nil) + } + + permissions, _ := json.Marshal(group.Permissions) + result := string(permissions) + expectedResult := fmt.Sprintf("{\"%s\":true}", permission.UUID) + if result != expectedResult { + t.Errorf("\ngot: %v\nwanted: %v", result, expectedResult) + } +} + +func TestGroupRemovePermission(t *testing.T) { + permission := CreatePermission("accessToSecrets") + group, _ := CreateGroup("mastersOfSecrets").AddPermission(permission) + + group = group.RemovePermission(permission) + + permissions, _ := json.Marshal(group.Permissions) + result := string(permissions) + expectedResult := "{}" + if result != expectedResult { + t.Errorf("\ngot: %v\nwanted: %v", result, expectedResult) + } +} + +func TestGroupHasPermission(t *testing.T) { + permission := CreatePermission("accessToSecrets") + permission2 := CreatePermission("accessToTheBathroom") + group, _ := CreateGroup("mastersOfSecrets").AddPermission(permission) + + if !group.HasPermission(permission) { + t.Errorf("\ngot: %t\nwanted: %t", false, true) + } + + if group.HasPermission(permission2) { + t.Errorf("\ngot: %t\nwanted: %t", true, false) + } +} diff --git a/pfug.go b/pfug.go new file mode 100644 index 0000000..23c803b --- /dev/null +++ b/pfug.go @@ -0,0 +1,33 @@ +package pfug + +import ( + "git.0x0001f346.de/andreas/utils" +) + +func CreateGroup(name string) Group { + return Group{ + UUID: utils.GenerateNewUUID(), + Name: name, + Members: map[string]bool{}, + Permissions: map[string]bool{}, + } +} + +func CreatePermission(name string) Permission { + return Permission{ + UUID: utils.GenerateNewUUID(), + Name: name, + } +} + +func CreateUser(username string, mail string, password string) User { + salt := utils.GenerateNewSHA256Sum() + + return User{ + UUID: utils.GenerateNewUUID(), + Username: username, + Mail: mail, + Salt: salt, + PasswordHash: generatePasswordHash(password, salt), + } +}