fleet/kitserver/service_users.go

package kitserver

import (
	"crypto/rand"
	"encoding/base64"
	"fmt"

	"github.com/kolide/kolide-ose/kolide"
	"golang.org/x/crypto/bcrypt"
	"golang.org/x/net/context"
)

func (s service) NewUser(ctx context.Context, p kolide.UserPayload) (*kolide.User, error) {
	user, err := userFromPayload(p, s.saltKeySize, s.bcryptCost)
	if err != nil {
		return nil, err
	}
	user, err = s.ds.NewUser(user)
	if err != nil {
		return nil, err
	}
	return user, nil
}

func userFromPayload(p kolide.UserPayload, keySize, cost int) (*kolide.User, error) {
	hashed, salt, err := hashPassword(*p.Password, keySize, cost)
	if err != nil {
		return nil, err
	}

	return &kolide.User{
		Username:           *p.Username,
		Email:              *p.Email,
		Admin:              falseIfNil(p.Admin),
		NeedsPasswordReset: falseIfNil(p.NeedsPasswordReset),
		Salt:               salt,
		Password:           hashed,
	}, nil
}

func hashPassword(plaintext string, keySize, cost int) ([]byte, string, error) {
	salt, err := generateRandomText(keySize)
	if err != nil {
		return nil, "", err
	}

	withSalt := []byte(fmt.Sprintf("%s%s", plaintext, salt))
	hashed, err := bcrypt.GenerateFromPassword(withSalt, cost)
	if err != nil {
		return nil, "", err
	}

	return hashed, salt, nil

}

// generateRandomText return a string generated by filling in keySize bytes with
// random data and then base64 encoding those bytes
func generateRandomText(keySize int) (string, error) {
	key := make([]byte, keySize)
	_, err := rand.Read(key)
	if err != nil {
		return "", err
	}

	return base64.StdEncoding.EncodeToString(key), nil
}

// helper to convert a bool pointer false
func falseIfNil(b *bool) bool {
	if b == nil {
		return false
	}
	return *b
}