Add "id-hash-limit" option to "ipfs add" command.

License: MIT
Signed-off-by: Kevin Atkinson <k@kevina.org>

Author: kevina

core/commands/add.go

@@ -14,8 +14,8 @@ import (
 	dag "github.com/ipfs/go-ipfs/merkledag"
 	dagtest "github.com/ipfs/go-ipfs/merkledag/test"
 	mfs "github.com/ipfs/go-ipfs/mfs"
-	ft "github.com/ipfs/go-ipfs/unixfs"
 	cide "github.com/ipfs/go-ipfs/thirdparty/cidextra"
+	ft "github.com/ipfs/go-ipfs/unixfs"
 
 	mh "gx/ipfs/QmZyZDi491cCNTLfAhwcaDii2Kg4pwKRkhqQzURGDvY6ua/go-multihash"
 	bstore "gx/ipfs/QmaG4DZ4JaqEfvPWt5nPPgoTzhc1tr1T3f4Nu9Jpdm8ymY/go-ipfs-blockstore"
@@ -44,6 +44,7 @@ const (
 	fstoreCacheOptionName = "fscache"
 	cidVersionOptionName  = "cid-version"
 	hashOptionName        = "hash"
+	idHashLimitOptionName = "id-hash-limit"
 )
 
 const adderOutChanSize = 8
@@ -120,6 +121,7 @@ You can now check what blocks have been created by:
 		cmdkit.BoolOption(fstoreCacheOptionName, "Check the filestore for pre-existing blocks. (experimental)"),
 		cmdkit.IntOption(cidVersionOptionName, "CID version. Defaults to 0 unless an option that depends on CIDv1 is passed. (experimental)"),
 		cmdkit.StringOption(hashOptionName, "Hash function to use. Implies CIDv1 if not sha2-256. (experimental)").WithDefault("sha2-256"),
+		cmdkit.IntOption(idHashLimitOptionName, "Id hash maxium size. -1 disables. (experimental)").WithDefault(-1),
 	},
 	PreRun: func(req *cmds.Request, env cmds.Environment) error {
 		quiet, _ := req.Options[quietOptionName].(bool)
@@ -173,6 +175,7 @@ You can now check what blocks have been created by:
 		fscache, _ := req.Options[fstoreCacheOptionName].(bool)
 		cidVer, cidVerSet := req.Options[cidVersionOptionName].(int)
 		hashFunStr, _ := req.Options[hashOptionName].(string)
+		idHashLimit, _ := req.Options[idHashLimitOptionName].(int)
 
 		// The arguments are subject to the following constraints.
 		//
@@ -282,6 +285,12 @@ You can now check what blocks have been created by:
 		fileAdder.NoCopy = nocopy
 		fileAdder.CidOpts = &cide.Opts{Prefix: prefix}
 
+		err = fileAdder.CidOpts.SetIdHashLimit(idHashLimit)
+		if err != nil {
+			res.SetError(err, cmdkit.ErrNormal)
+			return
+		}
+
 		if hash {
 			md := dagtest.Mock()
 			emptyDirNode := ft.EmptyDirNode()

thirdparty/cidextra/cidextra.go

@@ -1,23 +1,29 @@
 package cidextra
 
 import (
+	"fmt"
+
 	mh "gx/ipfs/QmZyZDi491cCNTLfAhwcaDii2Kg4pwKRkhqQzURGDvY6ua/go-multihash"
 	cid "gx/ipfs/QmcZfnkapfECQGcLZaf9B79NRg7cRa9EnZh4LSbkCzwNvY/go-cid"
 )
 
+var MaxIdHashLen = 64
+
 type Opts struct {
-	cid.Prefix 
+	cid.Prefix
 	idHashThres int // 0 disables, otherwise 1 + limit
 }
 
 // SetIdHashLimit is self explanatory
-func (o *Opts) SetIdHashLimit(l int) *Opts {
-	// FIXME: Check against hard limit
+func (o *Opts) SetIdHashLimit(l int) error {
+	if l > MaxIdHashLen {
+		return fmt.Errorf("identity hash limit of %d larger then maxium allowed limit of %d",
+			l, MaxIdHashLen)
+	}
 	o.idHashThres = l + 1
-	return o
+	return nil
 }
 
-
 // Sum returns a newly constructed Cid
 func (o Opts) Sum(data []byte) (*cid.Cid, error) {
 	if len(data) < o.idHashThres {

thirdparty/idstore/idstore.go

@@ -4,14 +4,14 @@ import (
 	"context"
 	"fmt"
 
+	cide "github.com/ipfs/go-ipfs/thirdparty/cidextra"
+
 	mh "gx/ipfs/QmZyZDi491cCNTLfAhwcaDii2Kg4pwKRkhqQzURGDvY6ua/go-multihash"
 	bls "gx/ipfs/QmaG4DZ4JaqEfvPWt5nPPgoTzhc1tr1T3f4Nu9Jpdm8ymY/go-ipfs-blockstore"
 	cid "gx/ipfs/QmcZfnkapfECQGcLZaf9B79NRg7cRa9EnZh4LSbkCzwNvY/go-cid"
 	blocks "gx/ipfs/Qmej7nf81hi2x2tvjRBF3mcp74sQyuDH4VMYDGd1YtXjb2/go-block-format"
 )
 
-var MaxIdHashLen = 64
-
 // idstore wraps a BlockStore to add support for identity hashes
 type idstore struct {
 	bs bls.Blockstore
@@ -26,9 +26,9 @@ func extractContents(k *cid.Cid) (bool, []byte, error) {
 	if err != nil || dmh.Code != mh.ID {
 		return false, nil, nil
 	}
-	if len(dmh.Digest) > MaxIdHashLen {
+	if len(dmh.Digest) > cide.MaxIdHashLen {
 		return true, nil, fmt.Errorf("identity hash of %d bytes is longer than maximum size of %d bytes",
-			len(dmh.Digest), MaxIdHashLen)
+			len(dmh.Digest), cide.MaxIdHashLen)
 	}
 	return true, dmh.Digest, nil
 }