diff options
Diffstat (limited to 'internal/base64dec')
24 files changed, 218 insertions, 0 deletions
diff --git a/internal/base64dec/base64.go b/internal/base64dec/base64.go new file mode 100644 index 0000000..dcb4b1c --- /dev/null +++ b/internal/base64dec/base64.go @@ -0,0 +1,130 @@ +// Copyright (C) 2022-2023 Luke Shumaker <lukeshu@lukeshu.com> +// +// SPDX-License-Identifier: GPL-2.0-or-later + +package base64dec + +import ( + "encoding/base64" + "io" + "strings" + + "git.lukeshu.com/go/lowmemjson/internal/fastio" +) + +type base64Decoder struct { + dst io.Writer + + err error + pos int64 + buf [4]byte + bufLen int +} + +func NewBase64Decoder(w io.Writer) interface { + io.WriteCloser + fastio.RuneWriter +} { + return &base64Decoder{ + dst: w, + } +} + +func (dec *base64Decoder) decodeByte(b byte) (byte, bool) { + const alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/" + n := strings.IndexByte(alphabet, b) + if n < 0 { + return 0, false + } + dec.pos++ + return byte(n), true +} + +func (dec *base64Decoder) decodeTuple(a, b, c, d byte) error { + var decodedLen int + var encoded [4]byte + var ok bool + + if a != '=' { + encoded[0], ok = dec.decodeByte(a) + if !ok { + return base64.CorruptInputError(dec.pos) + } + decodedLen++ + } + if b != '=' { + encoded[1], ok = dec.decodeByte(b) + if !ok { + return base64.CorruptInputError(dec.pos) + } + // do NOT increment decodedLen here + } + if c != '=' { + encoded[2], ok = dec.decodeByte(c) + if !ok { + return base64.CorruptInputError(dec.pos) + } + decodedLen++ + } + if d != '=' { + encoded[3], ok = dec.decodeByte(d) + if !ok { + return base64.CorruptInputError(dec.pos) + } + decodedLen++ + } + + val := 0 | + uint32(encoded[0])<<18 | + uint32(encoded[1])<<12 | + uint32(encoded[2])<<6 | + uint32(encoded[3])<<0 + var decoded [3]byte + decoded[0] = byte(val >> 16) + decoded[1] = byte(val >> 8) + decoded[2] = byte(val >> 0) + + _, err := dec.dst.Write(decoded[:decodedLen]) + return err +} + +func (dec *base64Decoder) Write(dat []byte) (int, error) { + if len(dat) == 0 { + return 0, nil + } + if dec.err != nil { + return 0, dec.err + } + var n int + if dec.bufLen > 0 { + n = copy(dec.buf[dec.bufLen:], dat) + dec.bufLen += n + if dec.bufLen < 4 { + return len(dat), nil + } + if err := dec.decodeTuple(dec.buf[0], dec.buf[1], dec.buf[2], dec.buf[3]); err != nil { + dec.err = err + return 0, dec.err + } + } + for ; n+3 < len(dat); n += 4 { + if err := dec.decodeTuple(dat[n], dat[n+1], dat[n+2], dat[n+3]); err != nil { + dec.err = err + return n, dec.err + } + } + dec.bufLen = copy(dec.buf[:], dat[n:]) + return len(dat), nil +} + +func (dec *base64Decoder) WriteRune(r rune) (int, error) { + return fastio.WriteRune(dec, r) +} + +func (dec *base64Decoder) Close() error { + if dec.bufLen == 0 { + return nil + } + copy(dec.buf[:], "====") + return dec.decodeTuple(dec.buf[0], dec.buf[1], dec.buf[2], dec.buf[3]) +} diff --git a/internal/base64dec/base64_test.go b/internal/base64dec/base64_test.go new file mode 100644 index 0000000..cb3063d --- /dev/null +++ b/internal/base64dec/base64_test.go @@ -0,0 +1,44 @@ +// Copyright (C) 2022-2023 Luke Shumaker <lukeshu@lukeshu.com> +// +// SPDX-License-Identifier: GPL-2.0-or-later + +package base64dec + +import ( + "bytes" + "encoding/base64" + "testing" + + "github.com/stretchr/testify/require" +) + +func b64encode(t *testing.T, input []byte) []byte { + var encoded bytes.Buffer + enc := base64.NewEncoder(base64.StdEncoding, &encoded) + _, err := enc.Write(input) + require.NoError(t, err) + require.NoError(t, enc.Close()) + return encoded.Bytes() +} + +func b64decode(t *testing.T, input []byte) []byte { + var decoded bytes.Buffer + dec := NewBase64Decoder(&decoded) + _, err := dec.Write(input) + require.NoError(t, err) + require.NoError(t, dec.Close()) + return decoded.Bytes() +} + +func FuzzBase64Decoder(f *testing.F) { + f.Fuzz(func(t *testing.T, input []byte) { + encoded := b64encode(t, input) + decoded := b64decode(t, encoded) + t.Logf("input b64 = %q", encoded) + t.Logf("expected decoded = %#v", input) + t.Logf("actual decoded = %#v", decoded) + if !bytes.Equal(input, decoded) { + t.Fail() + } + }) +} diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/06e2c9db80a08b67fad7f1a4606dc7419750995a57828aa25ea57fe7099d5c03 b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/06e2c9db80a08b67fad7f1a4606dc7419750995a57828aa25ea57fe7099d5c03 new file mode 100644 index 0000000..c3774e7 --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/06e2c9db80a08b67fad7f1a4606dc7419750995a57828aa25ea57fe7099d5c03 @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("0000000") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/24f53a36f8832fec65cac0aa0f3b43ec1c904414fa6d38f6fc288b0bbd69588a b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/24f53a36f8832fec65cac0aa0f3b43ec1c904414fa6d38f6fc288b0bbd69588a new file mode 100644 index 0000000..4c861db --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/24f53a36f8832fec65cac0aa0f3b43ec1c904414fa6d38f6fc288b0bbd69588a @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("000000000000000000000000000000000") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/2d49311ef22319f70a3590a86b406b9f2565987a4a3b6d7660ddc308b5b2fae2 b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/2d49311ef22319f70a3590a86b406b9f2565987a4a3b6d7660ddc308b5b2fae2 new file mode 100644 index 0000000..3d32e14 --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/2d49311ef22319f70a3590a86b406b9f2565987a4a3b6d7660ddc308b5b2fae2 @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("00000000000000000") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/356e28f5914a0f16f3cef81330f1d92060be4d694a93dedd654bf48743a7d2bd b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/356e28f5914a0f16f3cef81330f1d92060be4d694a93dedd654bf48743a7d2bd new file mode 100644 index 0000000..d08ef92 --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/356e28f5914a0f16f3cef81330f1d92060be4d694a93dedd654bf48743a7d2bd @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("00000000000000000000000000000000") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/582528ddfad69eb57775199a43e0f9fd5c94bba343ce7bb6724d4ebafe311ed4 b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/582528ddfad69eb57775199a43e0f9fd5c94bba343ce7bb6724d4ebafe311ed4 new file mode 100644 index 0000000..a96f559 --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/582528ddfad69eb57775199a43e0f9fd5c94bba343ce7bb6724d4ebafe311ed4 @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("0") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/60c81ee499a7f1e151b66b08f0a4ff81edd7cb53d00dce8ee0eaf31683996026 b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/60c81ee499a7f1e151b66b08f0a4ff81edd7cb53d00dce8ee0eaf31683996026 new file mode 100644 index 0000000..87c024d --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/60c81ee499a7f1e151b66b08f0a4ff81edd7cb53d00dce8ee0eaf31683996026 @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("0000000000000000000000000000000000000000000000000000") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/66498f377f38b53eebe1ceaa4a53e4de01a04efc02ac9cfda60f9815f80e9b9d b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/66498f377f38b53eebe1ceaa4a53e4de01a04efc02ac9cfda60f9815f80e9b9d new file mode 100644 index 0000000..959401e --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/66498f377f38b53eebe1ceaa4a53e4de01a04efc02ac9cfda60f9815f80e9b9d @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("000000") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/731951fe84fa6f3a7f6ee8adaa585d4f6a01f359a04737e51ffc70f16f480b9b b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/731951fe84fa6f3a7f6ee8adaa585d4f6a01f359a04737e51ffc70f16f480b9b new file mode 100644 index 0000000..bd1ae59 --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/731951fe84fa6f3a7f6ee8adaa585d4f6a01f359a04737e51ffc70f16f480b9b @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("000000000000000000000000000000000000000000000000") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/7d6367ba84cd18550920b5202cd1269174416ce32769c7f59376e76b7dd3129c b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/7d6367ba84cd18550920b5202cd1269174416ce32769c7f59376e76b7dd3129c new file mode 100644 index 0000000..09e0ad2 --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/7d6367ba84cd18550920b5202cd1269174416ce32769c7f59376e76b7dd3129c @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/8727b16d337d7b8187433233f3a90099024e580a6ba319ea2bf539880c50bd7c b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/8727b16d337d7b8187433233f3a90099024e580a6ba319ea2bf539880c50bd7c new file mode 100644 index 0000000..e8000f3 --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/8727b16d337d7b8187433233f3a90099024e580a6ba319ea2bf539880c50bd7c @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("00") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/9201a772731543760326638b8915f80863feab0ba0108183b3093934bdc0420c b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/9201a772731543760326638b8915f80863feab0ba0108183b3093934bdc0420c new file mode 100644 index 0000000..aac6b7d --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/9201a772731543760326638b8915f80863feab0ba0108183b3093934bdc0420c @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("00000000000000") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/92f75f690317ace34aeaae3fe39f5f2ff9830777253ff371c5ef6f403a0f8f0f b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/92f75f690317ace34aeaae3fe39f5f2ff9830777253ff371c5ef6f403a0f8f0f new file mode 100644 index 0000000..f3bf6d9 --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/92f75f690317ace34aeaae3fe39f5f2ff9830777253ff371c5ef6f403a0f8f0f @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("00000000000") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/93d6f7bc0d93f998c7b7fe654ff46010d6fa76f0a142c3523c42454f8ad10b07 b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/93d6f7bc0d93f998c7b7fe654ff46010d6fa76f0a142c3523c42454f8ad10b07 new file mode 100644 index 0000000..2e7f462 --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/93d6f7bc0d93f998c7b7fe654ff46010d6fa76f0a142c3523c42454f8ad10b07 @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("00000000") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/a7450fd77fc7c53cc5bd136874415dddfff5c586e662f21420caa7a94131a56a b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/a7450fd77fc7c53cc5bd136874415dddfff5c586e662f21420caa7a94131a56a new file mode 100644 index 0000000..c541f52 --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/a7450fd77fc7c53cc5bd136874415dddfff5c586e662f21420caa7a94131a56a @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("000000000000000000000000000000000000000000000000000") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/a95d2a0f87501a643d54218d2ad8112204672cc1fb30be297853616788208a5c b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/a95d2a0f87501a643d54218d2ad8112204672cc1fb30be297853616788208a5c new file mode 100644 index 0000000..5d56f29 --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/a95d2a0f87501a643d54218d2ad8112204672cc1fb30be297853616788208a5c @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/beed435aa2fee4819eab217543561dfd8001d4a44f53ceb664aaba86cebfaf21 b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/beed435aa2fee4819eab217543561dfd8001d4a44f53ceb664aaba86cebfaf21 new file mode 100644 index 0000000..4b4d59f --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/beed435aa2fee4819eab217543561dfd8001d4a44f53ceb664aaba86cebfaf21 @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/c2501043394e49f2477408be5ef9389790e33ed1886073dec445d4cf05bcd4b4 b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/c2501043394e49f2477408be5ef9389790e33ed1886073dec445d4cf05bcd4b4 new file mode 100644 index 0000000..ef9f9d4 --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/c2501043394e49f2477408be5ef9389790e33ed1886073dec445d4cf05bcd4b4 @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("000") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/caf81e9797b19c76c1fc4dbf537d4d81f389524539f402d13aa01f93a65ac7e9 b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/caf81e9797b19c76c1fc4dbf537d4d81f389524539f402d13aa01f93a65ac7e9 new file mode 100644 index 0000000..67322c7 --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/caf81e9797b19c76c1fc4dbf537d4d81f389524539f402d13aa01f93a65ac7e9 @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/cc90a4a40ae9b3beac70baf6d7821a5a6f3a90cabb033575790be91723593680 b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/cc90a4a40ae9b3beac70baf6d7821a5a6f3a90cabb033575790be91723593680 new file mode 100644 index 0000000..f195330 --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/cc90a4a40ae9b3beac70baf6d7821a5a6f3a90cabb033575790be91723593680 @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000\x04000000000000\r00000000000000000000") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/ec72f669d648d8d9b9f75a3b303897c59b11e4bfb7622f25ff251a92f182bc2a b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/ec72f669d648d8d9b9f75a3b303897c59b11e4bfb7622f25ff251a92f182bc2a new file mode 100644 index 0000000..5b0d392 --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/ec72f669d648d8d9b9f75a3b303897c59b11e4bfb7622f25ff251a92f182bc2a @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("0000000000000000000000000000000000000000") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/f34630c44c11bb13d27531927c5c1e65d159b70f39cd161da0dba348c1221ab3 b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/f34630c44c11bb13d27531927c5c1e65d159b70f39cd161da0dba348c1221ab3 new file mode 100644 index 0000000..a389d3c --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/f34630c44c11bb13d27531927c5c1e65d159b70f39cd161da0dba348c1221ab3 @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("00000") diff --git a/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/fd67efb09d433a1351a201281dbf6568628b4135c35c811dd9bce97620a75d43 b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/fd67efb09d433a1351a201281dbf6568628b4135c35c811dd9bce97620a75d43 new file mode 100644 index 0000000..17d10b2 --- /dev/null +++ b/internal/base64dec/testdata/fuzz/FuzzBase64Decoder/fd67efb09d433a1351a201281dbf6568628b4135c35c811dd9bce97620a75d43 @@ -0,0 +1,2 @@ +go test fuzz v1 +[]byte("000000000000") |