Files
phylum/server/internal/core/auth.go
2024-08-07 23:51:34 +05:30

104 lines
2.7 KiB
Go

package core
import (
"context"
"errors"
"time"
"unsafe"
"github.com/jackc/pgx/v5"
"github.com/jackc/pgx/v5/pgtype"
"github.com/shroff/phylum/server/internal/cryptutil"
"github.com/shroff/phylum/server/internal/db"
"golang.org/x/exp/rand"
)
const accessTokenLength = 16
var accessTokenValiditiy = pgtype.Interval{
Days: 30,
Valid: true,
}
var ErrCredentialsInvalid = errors.New("credentials invalid")
var ErrTokenInvalid = errors.New("token invalid")
var ErrTokenExpired = errors.New("token expired")
func (a App) VerifyUserPassword(ctx context.Context, username, password string) (User, error) {
if user, err := a.db.UserByUsername(ctx, username); err != nil {
if errors.Is(err, pgx.ErrNoRows) {
return nil, ErrCredentialsInvalid
}
return nil, err
} else {
if b, err := cryptutil.VerifyPassword(password, user.PasswordHash); err != nil {
return nil, err
} else if !b {
return nil, ErrCredentialsInvalid
}
if user, err := a.UserByID(ctx, user.ID); err != nil {
return nil, err
} else {
return user, nil
}
}
}
func (a App) CreateAccessToken(ctx context.Context, username, password string) (db.AccessToken, error) {
if user, err := a.VerifyUserPassword(ctx, username, password); err != nil {
return db.AccessToken{}, err
} else {
if token, err := a.db.InsertAccessToken(ctx, db.InsertAccessTokenParams{
ID: GenerateRandomString(accessTokenLength),
Validity: accessTokenValiditiy,
UserID: user.ID(),
}); err != nil {
return db.AccessToken{}, err
} else {
return token, nil
}
}
}
func (a App) VerifyAccessToken(ctx context.Context, accessToken string) (User, error) {
token, err := a.db.AccessTokenById(ctx, accessToken)
if errors.Is(err, pgx.ErrNoRows) {
return nil, ErrTokenInvalid
} else if err != nil {
return nil, err
}
if time.Now().After(token.Expires.Time) {
return nil, ErrTokenExpired
}
if user, err := a.UserByID(ctx, token.UserID); err != nil {
return nil, err
} else {
return user, nil
}
}
const (
letterBytes = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_"
letterIdxBits = 6 // 6 bits to represent a letter index
letterIdxMask = 1<<letterIdxBits - 1 // All 1-bits, as many as letterIdxBits
letterIdxMax = 64 / letterIdxBits // # of letter indices fitting in 64 bits
)
func GenerateRandomString(n int) string {
src := rand.NewSource(uint64(time.Now().UnixNano()))
b := make([]byte, n)
for i, cache, remain := n-1, src.Uint64(), letterIdxMax; i >= 0; {
if remain == 0 {
cache, remain = src.Uint64(), letterIdxMax
}
idx := int(cache & letterIdxMask)
// if idx < len(letterBytes)
b[i] = letterBytes[idx]
i--
cache >>= letterIdxBits
remain--
}
return *(*string)(unsafe.Pointer(&b))
}