Use base64.RawURLEncoding instead of defining base64Alphabet #1

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mrngm · 2019-09-02T13:22:16+02:00

mrngm commented

2019-09-02 13:22:16 +02:00

In https://gitea.hashru.nl/dsprenkels/rushlink/src/branch/master/handlers.go#L56 we can use base64.RawURLEncoding provided in the standard library.

E.g. https://gitea.hashru.nl/dsprenkels/rushlink/src/branch/master/handlers.go#L251

	var base64OwnerToken = make([]byte, 24)
	base64.RawURLEncoding.Encode(base64OwnerToken, storedPaste.OwnerToken[:])

In https://gitea.hashru.nl/dsprenkels/rushlink/src/branch/master/handlers.go#L56 we can use `base64.RawURLEncoding` provided in the standard library. E.g. https://gitea.hashru.nl/dsprenkels/rushlink/src/branch/master/handlers.go#L251 ``` var base64OwnerToken = make([]byte, 24) base64.RawURLEncoding.Encode(base64OwnerToken, storedPaste.OwnerToken[:]) ```

electricdusk commented

2019-09-10 18:02:12 +02:00

I am wondering if this is actually possible. Although we use the base64url alphabet, we do not use the base64 encoding. That is, because our IDs are generated in base 64, not in base 256. (I.e. they are not defined over bytes, but over sextets.)

Reusing base64.encodeURL, would be cool, but is obviously impossible.

Closing this as wontfix.

I am wondering if this is actually possible. Although we use the base64url *alphabet*, we do not use the base64 *encoding*. That is, because our IDs are generated in base 64, not in base *256*. (I.e. they are not defined over bytes, but over sextets.) Reusing [`base64.encodeURL`](https://golang.org/src/encoding/base64/base64.go?s=14692:14745#L36), would be cool, but is obviously impossible. Closing this as wontfix.

electricdusk closed this issue

2019-09-10 18:02:12 +02:00

mrngm commented

2019-09-10 22:59:07 +02:00

In 544c093c35/internal/handlers/handlers.go (L257) you do a base64 encoding over a slice of bytes, that seem ultimately filled through generateOwnerToken() in 544c093c35/internal/handlers/handlers.go (L373), where 16 bytes are sourced from rand.Read().

I'm not sure what you mean with

That is, because our IDs are generated in base 64, not in base 256.

because that is (obviously) not the case.

In https://gitea.hashru.nl/dsprenkels/rushlink/src/commit/544c093c353257bc67395e2a085f1c20318a182c/internal/handlers/handlers.go#L257 you do a base64 encoding over a slice of bytes, that seem ultimately filled through `generateOwnerToken()` in https://gitea.hashru.nl/dsprenkels/rushlink/src/commit/544c093c353257bc67395e2a085f1c20318a182c/internal/handlers/handlers.go#L373, where 16 bytes are sourced from `rand.Read()`. I'm not sure what you mean with > That is, because our IDs are generated in base 64, not in base 256. because that is (_obviously_) not the case.

mrngm reopened this issue

2019-09-10 22:59:07 +02:00

electricdusk referenced this issue from a commit

2019-09-11 00:13:00 +02:00

Use base64.RawURLEncoding as base64 encoder Fixes #1

electricdusk closed this issue

2019-09-11 00:13:00 +02:00

electricdusk commented

2019-09-11 00:13:44 +02:00

I now see what you mean. I fixed this; applying this patch:

diff --git a/internal/handlers/handlers.go b/internal/handlers/handlers.go
index 39077ac..a4a0a87 100644
--- a/internal/handlers/handlers.go
+++ b/internal/handlers/handlers.go
@@ -56,7 +56,7 @@ var ReservedPasteKeys [][]byte = [][]byte{[]byte("xd42"), []byte("example")}
 
 // Base64 encoding and decoding
 var base64Alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_"
-var base64Encoder = base64.NewEncoding(base64Alphabet).WithPadding(base64.NoPadding)
+var base64Encoder = base64.RawURLEncoding.WithPadding(base64.NoPadding)
 
 // Page contents
 var baseTemplate = template.New("empty")

I now see what you mean. I fixed this; applying this patch: ```diff diff --git a/internal/handlers/handlers.go b/internal/handlers/handlers.go index 39077ac..a4a0a87 100644 --- a/internal/handlers/handlers.go +++ b/internal/handlers/handlers.go @@ -56,7 +56,7 @@ var ReservedPasteKeys [][]byte = [][]byte{[]byte("xd42"), []byte("example")} // Base64 encoding and decoding var base64Alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_" -var base64Encoder = base64.NewEncoding(base64Alphabet).WithPadding(base64.NoPadding) +var base64Encoder = base64.RawURLEncoding.WithPadding(base64.NoPadding) // Page contents var baseTemplate = template.New("empty") ```

electricdusk commented

2019-09-11 00:14:55 +02:00

Note. It seems I misunderstood which base64 encoding was meant, because of the outdated line specifiers. I should just have Ctrl+F'd the code in the snippet.

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