github.com/google/trillian-examples@v0.0.0-20240520080811-0d40d35cef0e/binary_transparency/firmware/cmd/ft_personality/internal/trees/trees.go (about)

     1  // Copyright 2020 Google LLC. All Rights Reserved.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  // Package trees contains the personality tree configuration.
    16  package trees
    17  
    18  import (
    19  	"context"
    20  	"database/sql"
    21  	"fmt"
    22  	"time"
    23  
    24  	"github.com/google/trillian"
    25  	"github.com/google/trillian/client"
    26  	"google.golang.org/grpc"
    27  	"google.golang.org/protobuf/proto"
    28  	"google.golang.org/protobuf/types/known/durationpb"
    29  )
    30  
    31  // TreeStorage allows access to the configuration.
    32  type TreeStorage struct {
    33  	db *sql.DB
    34  }
    35  
    36  // NewTreeStorage sets up a TreeStorage using the given DB.
    37  func NewTreeStorage(db *sql.DB) *TreeStorage {
    38  	return &TreeStorage{
    39  		db: db,
    40  	}
    41  }
    42  
    43  // EnsureTree gets the tree for this personality, creating it if necessary.
    44  // Takes a connection to Trillian to use for initialization.
    45  // This is only safe in a single-replica deployment. In a real production setup
    46  // this provisioning would likely be done by a human ahead of time, or if this
    47  // style of automatic deployment was required then some kind of locking would
    48  // be required to ensure that only one log was created and used by all frontends.
    49  func (s *TreeStorage) EnsureTree(ctx context.Context, conn grpc.ClientConnInterface) (*trillian.Tree, error) {
    50  	if err := s.init(); err != nil {
    51  		return nil, err
    52  	}
    53  	res, err := s.getTree()
    54  	if err == nil {
    55  		return res, nil
    56  	}
    57  	if err == sql.ErrNoRows {
    58  		tree, err := s.createTree(ctx, conn)
    59  		if err != nil {
    60  			return nil, err
    61  		}
    62  		return tree, s.setTree(tree)
    63  	}
    64  	return nil, err
    65  }
    66  
    67  func (s *TreeStorage) createTree(ctx context.Context, conn grpc.ClientConnInterface) (*trillian.Tree, error) {
    68  	// N.B. Using the admin interface from the personality is not good practice for
    69  	// a production system. This simply allows a convenient way of getting the tree
    70  	// for the sake of getting the FT demo up and running.
    71  
    72  	ctr := &trillian.CreateTreeRequest{
    73  		Tree: &trillian.Tree{
    74  			TreeState:       trillian.TreeState_ACTIVE,
    75  			TreeType:        trillian.TreeType_LOG,
    76  			DisplayName:     "ft",
    77  			Description:     "binary transparency log",
    78  			MaxRootDuration: durationpb.New(time.Hour),
    79  		},
    80  	}
    81  
    82  	adminClient := trillian.NewTrillianAdminClient(conn)
    83  	logClient := trillian.NewTrillianLogClient(conn)
    84  
    85  	return client.CreateAndInitTree(ctx, ctr, adminClient, logClient)
    86  }
    87  
    88  func (s *TreeStorage) getTree() (*trillian.Tree, error) {
    89  	var raw []byte
    90  	if err := s.db.QueryRow("SELECT config FROM trees WHERE key = 'ft'").Scan(&raw); err != nil {
    91  		return nil, err
    92  	}
    93  
    94  	var res *trillian.Tree
    95  	if err := proto.Unmarshal(raw, res); err != nil {
    96  		return nil, err
    97  	}
    98  	return res, nil
    99  }
   100  
   101  func (s *TreeStorage) setTree(tree *trillian.Tree) error {
   102  	bs, err := proto.Marshal(tree)
   103  	if err != nil {
   104  		return err
   105  	}
   106  	_, err = s.db.Exec("INSERT INTO trees (key, config) VALUES (?, ?)", "ft", bs)
   107  	if err != nil {
   108  		return fmt.Errorf("failed to set tree: %w", err)
   109  	}
   110  	return nil
   111  }
   112  
   113  func (s *TreeStorage) init() error {
   114  	_, err := s.db.Exec("CREATE TABLE IF NOT EXISTS trees (key BLOB PRIMARY KEY, config BLOB)")
   115  	return err
   116  }