diff options
Diffstat (limited to 'vendor/golang.org/x/crypto/ssh/cipher.go')
| -rw-r--r-- | vendor/golang.org/x/crypto/ssh/cipher.go | 62 |
1 files changed, 32 insertions, 30 deletions
diff --git a/vendor/golang.org/x/crypto/ssh/cipher.go b/vendor/golang.org/x/crypto/ssh/cipher.go index 6a5b582aa..7554ed57a 100644 --- a/vendor/golang.org/x/crypto/ssh/cipher.go +++ b/vendor/golang.org/x/crypto/ssh/cipher.go @@ -8,6 +8,7 @@ import ( "crypto/aes" "crypto/cipher" "crypto/des" + "crypto/fips140" "crypto/rc4" "crypto/subtle" "encoding/binary" @@ -15,6 +16,7 @@ import ( "fmt" "hash" "io" + "slices" "golang.org/x/crypto/chacha20" "golang.org/x/crypto/internal/poly1305" @@ -93,41 +95,41 @@ func streamCipherMode(skip int, createFunc func(key, iv []byte) (cipher.Stream, } // cipherModes documents properties of supported ciphers. Ciphers not included -// are not supported and will not be negotiated, even if explicitly requested in -// ClientConfig.Crypto.Ciphers. -var cipherModes = map[string]*cipherMode{ - // Ciphers from RFC 4344, which introduced many CTR-based ciphers. Algorithms - // are defined in the order specified in the RFC. - CipherAES128CTR: {16, aes.BlockSize, streamCipherMode(0, newAESCTR)}, - CipherAES192CTR: {24, aes.BlockSize, streamCipherMode(0, newAESCTR)}, - CipherAES256CTR: {32, aes.BlockSize, streamCipherMode(0, newAESCTR)}, - - // Ciphers from RFC 4345, which introduces security-improved arcfour ciphers. - // They are defined in the order specified in the RFC. - InsecureCipherRC4128: {16, 0, streamCipherMode(1536, newRC4)}, - InsecureCipherRC4256: {32, 0, streamCipherMode(1536, newRC4)}, - - // Cipher defined in RFC 4253, which describes SSH Transport Layer Protocol. - // Note that this cipher is not safe, as stated in RFC 4253: "Arcfour (and - // RC4) has problems with weak keys, and should be used with caution." - // RFC 4345 introduces improved versions of Arcfour. - InsecureCipherRC4: {16, 0, streamCipherMode(0, newRC4)}, - - // AEAD ciphers - CipherAES128GCM: {16, 12, newGCMCipher}, - CipherAES256GCM: {32, 12, newGCMCipher}, - CipherChaCha20Poly1305: {64, 0, newChaCha20Cipher}, - +// are not supported and will not be negotiated, even if explicitly configured. +// When FIPS mode is enabled, only FIPS-approved algorithms are included. +var cipherModes = map[string]*cipherMode{} + +func init() { + cipherModes[CipherAES128CTR] = &cipherMode{16, aes.BlockSize, streamCipherMode(0, newAESCTR)} + cipherModes[CipherAES192CTR] = &cipherMode{24, aes.BlockSize, streamCipherMode(0, newAESCTR)} + cipherModes[CipherAES256CTR] = &cipherMode{32, aes.BlockSize, streamCipherMode(0, newAESCTR)} + // Use of GCM with arbitrary IVs is not allowed in FIPS 140-only mode, + // we'll wire it up to NewGCMForSSH in Go 1.26. + // + // For now it means we'll work with fips140=on but not fips140=only. + cipherModes[CipherAES128GCM] = &cipherMode{16, 12, newGCMCipher} + cipherModes[CipherAES256GCM] = &cipherMode{32, 12, newGCMCipher} + + if fips140.Enabled() { + defaultCiphers = slices.DeleteFunc(defaultCiphers, func(algo string) bool { + _, ok := cipherModes[algo] + return !ok + }) + return + } + + cipherModes[CipherChaCha20Poly1305] = &cipherMode{64, 0, newChaCha20Cipher} + // Insecure ciphers not included in the default configuration. + cipherModes[InsecureCipherRC4128] = &cipherMode{16, 0, streamCipherMode(1536, newRC4)} + cipherModes[InsecureCipherRC4256] = &cipherMode{32, 0, streamCipherMode(1536, newRC4)} + cipherModes[InsecureCipherRC4] = &cipherMode{16, 0, streamCipherMode(0, newRC4)} // CBC mode is insecure and so is not included in the default config. // (See https://www.ieee-security.org/TC/SP2013/papers/4977a526.pdf). If absolutely // needed, it's possible to specify a custom Config to enable it. // You should expect that an active attacker can recover plaintext if // you do. - InsecureCipherAES128CBC: {16, aes.BlockSize, newAESCBCCipher}, - - // 3des-cbc is insecure and is not included in the default - // config. - InsecureCipherTripleDESCBC: {24, des.BlockSize, newTripleDESCBCCipher}, + cipherModes[InsecureCipherAES128CBC] = &cipherMode{16, aes.BlockSize, newAESCBCCipher} + cipherModes[InsecureCipherTripleDESCBC] = &cipherMode{24, des.BlockSize, newTripleDESCBCCipher} } // prefixLen is the length of the packet prefix that contains the packet length |