diff options
Diffstat (limited to 'crypto-vala/src/cipher.vala')
| -rw-r--r-- | crypto-vala/src/cipher.vala | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/crypto-vala/src/cipher.vala b/crypto-vala/src/cipher.vala new file mode 100644 index 00000000..306dafa8 --- /dev/null +++ b/crypto-vala/src/cipher.vala @@ -0,0 +1,152 @@ +namespace Crypto { +public class SymmetricCipher { + private GCrypt.Cipher.Cipher cipher; + + public static bool supports(string algo_name) { + GCrypt.Cipher.Algorithm algo; + GCrypt.Cipher.Mode mode; + GCrypt.Cipher.Flag flags; + return parse(algo_name, out algo, out mode, out flags); + } + + private static unowned string mode_to_string(GCrypt.Cipher.Mode mode) { + switch (mode) { + case GCrypt.Cipher.Mode.ECB: return "ECB"; + case GCrypt.Cipher.Mode.CFB: return "CFB"; + case GCrypt.Cipher.Mode.CBC: return "CBC"; + case GCrypt.Cipher.Mode.STREAM: return "STREAM"; + case GCrypt.Cipher.Mode.OFB: return "OFB"; + case GCrypt.Cipher.Mode.CTR: return "CTR"; + case GCrypt.Cipher.Mode.AESWRAP: return "AESWRAP"; + case GCrypt.Cipher.Mode.GCM: return "GCM"; + case GCrypt.Cipher.Mode.POLY1305: return "POLY1305"; + case GCrypt.Cipher.Mode.OCB: return "OCB"; + case GCrypt.Cipher.Mode.CFB8: return "CFB8"; + // case GCrypt.Cipher.Mode.XTS: return "XTS"; // Not supported in gcrypt < 1.8 + } + return "NONE"; + } + + private static GCrypt.Cipher.Mode mode_from_string(string name) { + switch (name) { + case "ECB": return GCrypt.Cipher.Mode.ECB; + case "CFB": return GCrypt.Cipher.Mode.CFB; + case "CBC": return GCrypt.Cipher.Mode.CBC; + case "STREAM": return GCrypt.Cipher.Mode.STREAM; + case "OFB": return GCrypt.Cipher.Mode.OFB; + case "CTR": return GCrypt.Cipher.Mode.CTR; + case "AESWRAP": return GCrypt.Cipher.Mode.AESWRAP; + case "GCM": return GCrypt.Cipher.Mode.GCM; + case "POLY1305": return GCrypt.Cipher.Mode.POLY1305; + case "OCB": return GCrypt.Cipher.Mode.OCB; + case "CFB8": return GCrypt.Cipher.Mode.CFB8; + // case "XTS": return GCrypt.Cipher.Mode.XTS; // Not supported in gcrypt < 1.8 + } + return GCrypt.Cipher.Mode.NONE; + } + + private static string flags_to_string(GCrypt.Cipher.Flag flags) { + string? s = null; + if ((GCrypt.Cipher.Flag.CBC_MAC & flags) != 0) s = (s == null ? "" : @"$s-") + "MAC"; + if ((GCrypt.Cipher.Flag.CBC_CTS & flags) != 0) s = (s == null ? "" : @"$s-") + "CTS"; + if ((GCrypt.Cipher.Flag.ENABLE_SYNC & flags) != 0) s = (s == null ? "" : @"$s-") + "SYNC"; + if ((GCrypt.Cipher.Flag.SECURE & flags) != 0) s = (s == null ? "" : @"$s-") + "SECURE"; + return s ?? "NONE"; + } + + private static GCrypt.Cipher.Flag flag_from_string(string flag_name) { + if (flag_name == "SECURE") return GCrypt.Cipher.Flag.SECURE; + if (flag_name == "SYNC") return GCrypt.Cipher.Flag.ENABLE_SYNC; + if (flag_name == "CTS") return GCrypt.Cipher.Flag.CBC_CTS; + if (flag_name == "MAC") return GCrypt.Cipher.Flag.CBC_MAC; + return 0; + } + + private static GCrypt.Cipher.Flag flags_from_string(string flag_names) { + GCrypt.Cipher.Flag flags = 0; + foreach(string flag in flag_names.split("-")) { + flags |= flag_from_string(flag); + } + return flags; + } + + private static bool parse(string algo_name, out GCrypt.Cipher.Algorithm algo, out GCrypt.Cipher.Mode mode, out GCrypt.Cipher.Flag flags) { + algo = GCrypt.Cipher.Algorithm.NONE; + mode = GCrypt.Cipher.Mode.NONE; + flags = 0; + string[] algo_parts = algo_name.split("-", 3); + + algo = GCrypt.Cipher.Algorithm.from_string(algo_parts[0]); + if (algo_parts.length >= 2) { + mode = mode_from_string(algo_parts[1]); + } + if (algo_parts.length == 3) { + flags |= flags_from_string(algo_parts[2]); + } + return to_algo_name(algo, mode, flags) == algo_name; + } + + private static string to_algo_name(GCrypt.Cipher.Algorithm algo = GCrypt.Cipher.Algorithm.NONE, GCrypt.Cipher.Mode mode = GCrypt.Cipher.Mode.NONE, GCrypt.Cipher.Flag flags = 0) { + if (flags != 0) { + return @"$algo-$(mode_to_string(mode))-$(flags_to_string(flags))"; + } else if (mode != GCrypt.Cipher.Mode.NONE) { + return @"$algo-$(mode_to_string(mode))"; + } else { + return algo.to_string(); + } + } + + public SymmetricCipher(string algo_name) throws Error { + GCrypt.Cipher.Algorithm algo; + GCrypt.Cipher.Mode mode; + GCrypt.Cipher.Flag flags; + if (parse(algo_name, out algo, out mode, out flags)) { + this.gcrypt(algo, mode, flags); + } else { + throw new Error.ILLEGAL_ARGUMENTS(@"The algorithm $algo_name is not supported"); + } + } + + private SymmetricCipher.gcrypt(GCrypt.Cipher.Algorithm algo, GCrypt.Cipher.Mode mode, GCrypt.Cipher.Flag flags) throws Error { + may_throw_gcrypt_error(GCrypt.Cipher.Cipher.open(out this.cipher, algo, mode, flags)); + } + + public void set_key(uint8[] key) throws Error { + may_throw_gcrypt_error(cipher.set_key(key)); + } + + public void set_iv(uint8[] iv) throws Error { + may_throw_gcrypt_error(cipher.set_iv(iv)); + } + + public void set_counter_vector(uint8[] ctr) throws Error { + may_throw_gcrypt_error(cipher.set_counter_vector(ctr)); + } + + public void reset() throws Error { + may_throw_gcrypt_error(cipher.reset()); + } + + public uint8[] get_tag(size_t taglen) throws Error { + uint8[] tag = new uint8[taglen]; + may_throw_gcrypt_error(cipher.get_tag(tag)); + return tag; + } + + public void check_tag(uint8[] tag) throws Error { + may_throw_gcrypt_error(cipher.check_tag(tag)); + } + + public void encrypt(uint8[] output, uint8[] input) throws Error { + may_throw_gcrypt_error(cipher.encrypt(output, input)); + } + + public void decrypt(uint8[] output, uint8[] input) throws Error { + may_throw_gcrypt_error(cipher.decrypt(output, input)); + } + + public void sync() throws Error { + may_throw_gcrypt_error(cipher.sync()); + } +} +} |