Replace all calls to naked panic() with log.Panic()

We want all panics to show up in the syslog.

11 files changed, 48 insertions, 38 deletions

diff --git a/internal/contentenc/content.go b/internal/contentenc/content.go
index c42a844..322163a 100644
--- a/internal/contentenc/content.go
+++ b/internal/contentenc/content.go
@@ -6,6 +6,7 @@ import (
 	"encoding/binary"
 	"encoding/hex"
 	"errors"
+	"log"
 
 	"github.com/rfjakob/gocryptfs/internal/cryptocore"
 	"github.com/rfjakob/gocryptfs/internal/tlog"
@@ -152,7 +153,7 @@ func (be *ContentEnc) EncryptBlock(plaintext []byte, blockNo uint64, fileID []by
 // This function can only be used in SIV mode.
 func (be *ContentEnc) EncryptBlockNonce(plaintext []byte, blockNo uint64, fileID []byte, nonce []byte) []byte {
 	if be.cryptoCore.AEADBackend != cryptocore.BackendAESSIV {
-		panic("deterministic nonces are only secure in SIV mode")
+		log.Panic("deterministic nonces are only secure in SIV mode")
 	}
 	return be.doEncryptBlock(plaintext, blockNo, fileID, nonce)
 }
@@ -166,7 +167,7 @@ func (be *ContentEnc) doEncryptBlock(plaintext []byte, blockNo uint64, fileID []
 		return plaintext
 	}
 	if len(nonce) != be.cryptoCore.IVLen {
-		panic("wrong nonce length")
+		log.Panic("wrong nonce length")
 	}
 
 	// Authenticate block with block number and file ID
diff --git a/internal/contentenc/file_header.go b/internal/contentenc/file_header.go
index 9ae5ae9..5c05818 100644
--- a/internal/contentenc/file_header.go
+++ b/internal/contentenc/file_header.go
@@ -7,6 +7,7 @@ package contentenc
 import (
 	"encoding/binary"
 	"fmt"
+	"log"
 
 	"github.com/rfjakob/gocryptfs/internal/cryptocore"
 )
@@ -30,7 +31,7 @@ type FileHeader struct {
 // Pack - serialize fileHeader object
 func (h *FileHeader) Pack() []byte {
 	if len(h.ID) != headerIDLen || h.Version != CurrentVersion {
-		panic("FileHeader object not properly initialized")
+		log.Panic("FileHeader object not properly initialized")
 	}
 	buf := make([]byte, HeaderLen)
 	binary.BigEndian.PutUint16(buf[0:headerVersionLen], h.Version)
diff --git a/internal/cryptocore/cryptocore.go b/internal/cryptocore/cryptocore.go
index db82f56..13b278f 100644
--- a/internal/cryptocore/cryptocore.go
+++ b/internal/cryptocore/cryptocore.go
@@ -7,6 +7,7 @@ import (
 	"crypto/cipher"
 	"crypto/sha512"
 	"fmt"
+	"log"
 
 	"github.com/rfjakob/gocryptfs/internal/siv_aead"
 	"github.com/rfjakob/gocryptfs/internal/stupidgcm"
@@ -50,7 +51,7 @@ type CryptoCore struct {
 // key in gocryptfs.conf.
 func New(key []byte, backend BackendTypeEnum, IVBitLen int) *CryptoCore {
 	if len(key) != KeyLen {
-		panic(fmt.Sprintf("Unsupported key length %d", len(key)))
+		log.Panic(fmt.Sprintf("Unsupported key length %d", len(key)))
 	}
 	// We want the IV size in bytes
 	IVLen := IVBitLen / 8
@@ -59,14 +60,14 @@ func New(key []byte, backend BackendTypeEnum, IVBitLen int) *CryptoCore {
 	// Content encryption uses BlockCipher only if useOpenssl=false.
 	blockCipher, err := aes.NewCipher(key)
 	if err != nil {
-		panic(err)
+		log.Panic(err)
 	}
 
 	var aeadCipher cipher.AEAD
 	switch backend {
 	case BackendOpenSSL:
 		if IVLen != 16 {
-			panic("stupidgcm only supports 128-bit IVs")
+			log.Panic("stupidgcm only supports 128-bit IVs")
 		}
 		aeadCipher = stupidgcm.New(key)
 	case BackendGoGCM:
@@ -74,7 +75,7 @@ func New(key []byte, backend BackendTypeEnum, IVBitLen int) *CryptoCore {
 	case BackendAESSIV:
 		if IVLen != 16 {
 			// SIV supports any nonce size, but we only use 16.
-			panic("AES-SIV must use 16-byte nonces")
+			log.Panic("AES-SIV must use 16-byte nonces")
 		}
 		// AES-SIV uses 1/2 of the key for authentication, 1/2 for
 		// encryption, so we need a 64-bytes key for AES-256. Derive it from
@@ -82,10 +83,10 @@ func New(key []byte, backend BackendTypeEnum, IVBitLen int) *CryptoCore {
 		key64 := sha512.Sum512(key)
 		aeadCipher = siv_aead.New(key64[:])
 	default:
-		panic("unknown backend cipher")
+		log.Panic("unknown backend cipher")
 	}
 	if err != nil {
-		panic(err)
+		log.Panic(err)
 	}
 
 	return &CryptoCore{
diff --git a/internal/cryptocore/nonce.go b/internal/cryptocore/nonce.go
index 973d2d8..3f56cc9 100644
--- a/internal/cryptocore/nonce.go
+++ b/internal/cryptocore/nonce.go
@@ -6,6 +6,7 @@ import (
 	"encoding/binary"
 	"encoding/hex"
 	"fmt"
+	"log"
 
 	"github.com/rfjakob/gocryptfs/internal/tlog"
 )
@@ -15,7 +16,7 @@ func RandBytes(n int) []byte {
 	b := make([]byte, n)
 	_, err := rand.Read(b)
 	if err != nil {
-		panic("Failed to read random bytes: " + err.Error())
+		log.Panic("Failed to read random bytes: " + err.Error())
 	}
 	return b
 }
@@ -37,7 +38,7 @@ func (n *nonceGenerator) Get() []byte {
 	tlog.Debug.Printf("nonceGenerator.Get(): %s\n", hex.EncodeToString(nonce))
 	if bytes.Equal(nonce, n.lastNonce) {
 		m := fmt.Sprintf("Got the same nonce twice: %s. This should never happen!", hex.EncodeToString(nonce))
-		panic(m)
+		log.Panic(m)
 	}
 	n.lastNonce = nonce
 	return nonce
diff --git a/internal/fusefrontend_reverse/reverse_longnames.go b/internal/fusefrontend_reverse/reverse_longnames.go
index 0234397..24335bd 100644
--- a/internal/fusefrontend_reverse/reverse_longnames.go
+++ b/internal/fusefrontend_reverse/reverse_longnames.go
@@ -1,6 +1,7 @@
 package fusefrontend_reverse
 
 import (
+	"log"
 	"os"
 	"path/filepath"
 	"sync"
@@ -65,7 +66,7 @@ func (rfs *ReverseFS) findLongnameParent(dir string, dirIV []byte, longname stri
 		}
 		cName := rfs.nameTransform.EncryptName(plaintextName, dirIV)
 		if len(cName) <= syscall.NAME_MAX {
-			panic("logic error or wrong shortNameMax constant?")
+			log.Panic("logic error or wrong shortNameMax constant?")
 		}
 		hName := nametransform.HashLongName(cName)
 		longnameParentCache[hName] = plaintextName
diff --git a/internal/fusefrontend_reverse/rfs.go b/internal/fusefrontend_reverse/rfs.go
index aca4b90..4a2cc06 100644
--- a/internal/fusefrontend_reverse/rfs.go
+++ b/internal/fusefrontend_reverse/rfs.go
@@ -3,6 +3,7 @@ package fusefrontend_reverse
 import (
 	"encoding/base64"
 	"fmt"
+	"log"
 	"os"
 	"path/filepath"
 	"sync"
@@ -53,7 +54,7 @@ var _ pathfs.FileSystem = &ReverseFS{}
 // ReverseFS provides an encrypted view.
 func NewFS(args fusefrontend.Args) *ReverseFS {
 	if args.CryptoBackend != cryptocore.BackendAESSIV {
-		panic("reverse mode must use AES-SIV, everything else is insecure")
+		log.Panic("reverse mode must use AES-SIV, everything else is insecure")
 	}
 	initLongnameCache()
 	cryptoCore := cryptocore.New(args.Masterkey, args.CryptoBackend, contentenc.DefaultIVBits)
diff --git a/internal/nametransform/pad16.go b/internal/nametransform/pad16.go
index e512828..2b30bcb 100644
--- a/internal/nametransform/pad16.go
+++ b/internal/nametransform/pad16.go
@@ -4,6 +4,7 @@ import (
 	"crypto/aes"
 	"errors"
 	"fmt"
+	"log"
 )
 
 // pad16 - pad data to AES block size (=16 byte) using standard PKCS#7 padding
@@ -11,7 +12,7 @@ import (
 func pad16(orig []byte) (padded []byte) {
 	oldLen := len(orig)
 	if oldLen == 0 {
-		panic("Padding zero-length string makes no sense")
+		log.Panic("Padding zero-length string makes no sense")
 	}
 	padLen := aes.BlockSize - oldLen%aes.BlockSize
 	if padLen == 0 {
diff --git a/internal/siv_aead/siv_aead.go b/internal/siv_aead/siv_aead.go
index c68ecdb..6cfa937 100644
--- a/internal/siv_aead/siv_aead.go
+++ b/internal/siv_aead/siv_aead.go
@@ -4,6 +4,7 @@ package siv_aead
 
 import (
 	"crypto/cipher"
+	"log"
 
 	"github.com/jacobsa/crypto/siv"
 )
@@ -34,7 +35,7 @@ func (s *sivAead) Overhead() int {
 func (s *sivAead) Seal(dst, nonce, plaintext, authData []byte) []byte {
 	if len(nonce) != 16 {
 		// SIV supports any nonce size, but in gocryptfs we exclusively use 16.
-		panic("nonce must be 16 bytes long")
+		log.Panic("nonce must be 16 bytes long")
 	}
 	// https://github.com/jacobsa/crypto/blob/master/siv/encrypt.go#L48:
 	// As per RFC 5297 section 3, you may use this function for nonce-based
@@ -43,7 +44,7 @@ func (s *sivAead) Seal(dst, nonce, plaintext, authData []byte) []byte {
 	associated := [][]byte{authData, nonce}
 	out, err := siv.Encrypt(dst, s.key, plaintext, associated)
 	if err != nil {
-		panic(err)
+		log.Panic(err)
 	}
 	return out
 }
@@ -52,7 +53,7 @@ func (s *sivAead) Seal(dst, nonce, plaintext, authData []byte) []byte {
 func (s *sivAead) Open(dst, nonce, ciphertext, authData []byte) ([]byte, error) {
 	if len(nonce) != 16 {
 		// SIV supports any nonce size, but in gocryptfs we exclusively use 16.
-		panic("nonce must be 16 bytes long")
+		log.Panic("nonce must be 16 bytes long")
 	}
 	associated := [][]byte{authData, nonce}
 	dec, err := siv.Decrypt(s.key, ciphertext, associated)
diff --git a/internal/stupidgcm/stupidgcm.go b/internal/stupidgcm/stupidgcm.go
index 6e551f5..a1a5a14 100644
--- a/internal/stupidgcm/stupidgcm.go
+++ b/internal/stupidgcm/stupidgcm.go
@@ -62,28 +62,28 @@ func (g stupidGCM) Seal(dst, iv, in, authData []byte) []byte {
 	// Create scratch space "context"
 	ctx := C.EVP_CIPHER_CTX_new()
 	if ctx == nil {
-		panic("EVP_CIPHER_CTX_new failed")
+		log.Panic("EVP_CIPHER_CTX_new failed")
 	}
 
 	// Set cipher to AES-256
 	if C.EVP_EncryptInit_ex(ctx, C.EVP_aes_256_gcm(), nil, nil, nil) != 1 {
-		panic("EVP_EncryptInit_ex I failed")
+		log.Panic("EVP_EncryptInit_ex I failed")
 	}
 
 	// Use 16-byte IV
 	if C.EVP_CIPHER_CTX_ctrl(ctx, C.EVP_CTRL_GCM_SET_IVLEN, ivLen, nil) != 1 {
-		panic("EVP_CIPHER_CTX_ctrl EVP_CTRL_GCM_SET_IVLEN failed")
+		log.Panic("EVP_CIPHER_CTX_ctrl EVP_CTRL_GCM_SET_IVLEN failed")
 	}
 
 	// Set key and IV
 	if C.EVP_EncryptInit_ex(ctx, nil, nil, (*C.uchar)(&g.key[0]), (*C.uchar)(&iv[0])) != 1 {
-		panic("EVP_EncryptInit_ex II failed")
+		log.Panic("EVP_EncryptInit_ex II failed")
 	}
 
 	// Provide authentication data
 	var resultLen C.int
 	if C.EVP_EncryptUpdate(ctx, nil, &resultLen, (*C.uchar)(&authData[0]), C.int(len(authData))) != 1 {
-		panic("EVP_EncryptUpdate authData failed")
+		log.Panic("EVP_EncryptUpdate authData failed")
 	}
 	if int(resultLen) != len(authData) {
 		log.Panicf("Unexpected length %d", resultLen)
@@ -91,7 +91,7 @@ func (g stupidGCM) Seal(dst, iv, in, authData []byte) []byte {
 
 	// Encrypt "in" into "buf"
 	if C.EVP_EncryptUpdate(ctx, (*C.uchar)(&buf[0]), &resultLen, (*C.uchar)(&in[0]), C.int(len(in))) != 1 {
-		panic("EVP_EncryptUpdate failed")
+		log.Panic("EVP_EncryptUpdate failed")
 	}
 	if int(resultLen) != len(in) {
 		log.Panicf("Unexpected length %d", resultLen)
@@ -101,7 +101,7 @@ func (g stupidGCM) Seal(dst, iv, in, authData []byte) []byte {
 	// Because GCM is a stream encryption, this will not write out any data.
 	dummy := make([]byte, 16)
 	if C.EVP_EncryptFinal_ex(ctx, (*C.uchar)(&dummy[0]), &resultLen) != 1 {
-		panic("EVP_EncryptFinal_ex failed")
+		log.Panic("EVP_EncryptFinal_ex failed")
 	}
 	if resultLen != 0 {
 		log.Panicf("Unexpected length %d", resultLen)
@@ -109,7 +109,7 @@ func (g stupidGCM) Seal(dst, iv, in, authData []byte) []byte {
 
 	// Get GMAC tag and append it to the ciphertext in "buf"
 	if C.EVP_CIPHER_CTX_ctrl(ctx, C.EVP_CTRL_GCM_GET_TAG, tagLen, (unsafe.Pointer)(&buf[len(in)])) != 1 {
-		panic("EVP_CIPHER_CTX_ctrl EVP_CTRL_GCM_GET_TAG failed")
+		log.Panic("EVP_CIPHER_CTX_ctrl EVP_CTRL_GCM_GET_TAG failed")
 	}
 
 	// Free scratch space
@@ -135,33 +135,33 @@ func (g stupidGCM) Open(dst, iv, in, authData []byte) ([]byte, error) {
 	// Create scratch space "context"
 	ctx := C.EVP_CIPHER_CTX_new()
 	if ctx == nil {
-		panic("EVP_CIPHER_CTX_new failed")
+		log.Panic("EVP_CIPHER_CTX_new failed")
 	}
 
 	// Set cipher to AES-256
 	if C.EVP_DecryptInit_ex(ctx, C.EVP_aes_256_gcm(), nil, nil, nil) != 1 {
-		panic("EVP_DecryptInit_ex I failed")
+		log.Panic("EVP_DecryptInit_ex I failed")
 	}
 
 	// Use 16-byte IV
 	if C.EVP_CIPHER_CTX_ctrl(ctx, C.EVP_CTRL_GCM_SET_IVLEN, ivLen, nil) != 1 {
-		panic("EVP_CIPHER_CTX_ctrl EVP_CTRL_GCM_SET_IVLEN failed")
+		log.Panic("EVP_CIPHER_CTX_ctrl EVP_CTRL_GCM_SET_IVLEN failed")
 	}
 
 	// Set key and IV
 	if C.EVP_DecryptInit_ex(ctx, nil, nil, (*C.uchar)(&g.key[0]), (*C.uchar)(&iv[0])) != 1 {
-		panic("EVP_DecryptInit_ex II failed")
+		log.Panic("EVP_DecryptInit_ex II failed")
 	}
 
 	// Set expected GMAC tag
 	if C.EVP_CIPHER_CTX_ctrl(ctx, C.EVP_CTRL_GCM_SET_TAG, tagLen, (unsafe.Pointer)(&tag[0])) != 1 {
-		panic("EVP_CIPHER_CTX_ctrl failed")
+		log.Panic("EVP_CIPHER_CTX_ctrl failed")
 	}
 
 	// Provide authentication data
 	var resultLen C.int
 	if C.EVP_DecryptUpdate(ctx, nil, &resultLen, (*C.uchar)(&authData[0]), C.int(len(authData))) != 1 {
-		panic("EVP_DecryptUpdate authData failed")
+		log.Panic("EVP_DecryptUpdate authData failed")
 	}
 	if int(resultLen) != len(authData) {
 		log.Panicf("Unexpected length %d", resultLen)
@@ -169,7 +169,7 @@ func (g stupidGCM) Open(dst, iv, in, authData []byte) ([]byte, error) {
 
 	// Decrypt "ciphertext" into "buf"
 	if C.EVP_DecryptUpdate(ctx, (*C.uchar)(&buf[0]), &resultLen, (*C.uchar)(&ciphertext[0]), C.int(len(ciphertext))) != 1 {
-		panic("EVP_DecryptUpdate failed")
+		log.Panic("EVP_DecryptUpdate failed")
 	}
 	if int(resultLen) != len(ciphertext) {
 		log.Panicf("Unexpected length %d", resultLen)
diff --git a/internal/stupidgcm/stupidgcm_test.go b/internal/stupidgcm/stupidgcm_test.go
index 3c11dfe..d6c0714 100644
--- a/internal/stupidgcm/stupidgcm_test.go
+++ b/internal/stupidgcm/stupidgcm_test.go
@@ -13,6 +13,7 @@ import (
 	"crypto/cipher"
 	"crypto/rand"
 	"encoding/hex"
+	"log"
 	"testing"
 
 	// For benchmark comparison
@@ -24,7 +25,7 @@ func randBytes(n int) []byte {
 	b := make([]byte, n)
 	_, err := rand.Read(b)
 	if err != nil {
-		panic("Failed to read random bytes: " + err.Error())
+		log.Panic("Failed to read random bytes: " + err.Error())
 	}
 	return b
 }
diff --git a/internal/stupidgcm/without_openssl.go b/internal/stupidgcm/without_openssl.go
index 91dd33c..9fb245e 100644
--- a/internal/stupidgcm/without_openssl.go
+++ b/internal/stupidgcm/without_openssl.go
@@ -3,6 +3,7 @@
 package stupidgcm
 
 import (
+	"log"
 	"os"
 
 	"github.com/rfjakob/gocryptfs/internal/tlog"
@@ -24,25 +25,25 @@ func New(_ []byte) stupidGCM {
 	errExit()
 	// This panic is never reached, but having it here stops the Go compiler
 	// from complaining about the missing return code.
-	panic("")
+	log.Panic("")
 }
 
 func (g stupidGCM) NonceSize() int {
 	errExit()
-	panic("")
+	log.Panic("")
 }
 
 func (g stupidGCM) Overhead() int {
 	errExit()
-	panic("")
+	log.Panic("")
 }
 
 func (g stupidGCM) Seal(_, _, _, _ []byte) []byte {
 	errExit()
-	panic("")
+	log.Panic("")
 }
 
 func (g stupidGCM) Open(_, _, _, _ []byte) ([]byte, error) {
 	errExit()
-	panic("")
+	log.Panic("")
 }