| ... | @@ -19,7 +19,6 @@ pub const State = struct { | ... | @@ -19,7 +19,6 @@ pub const State = struct { |
| 19 | pub const BLOCKBYTES = 48; | 19 | pub const BLOCKBYTES = 48; |
| 20 | pub const RATE = 16; | 20 | pub const RATE = 16; |
| 21 | | 21 | |
| 22 | // TODO: https://github.com/ziglang/zig/issues/2673#issuecomment-501763017 | | |
| 23 | data: [BLOCKBYTES / 4]u32, | 22 | data: [BLOCKBYTES / 4]u32, |
| 24 | | 23 | |
| 25 | const Self = @This(); | 24 | const Self = @This(); |
| ... | @@ -134,6 +133,8 @@ pub const Hash = struct { | ... | @@ -134,6 +133,8 @@ pub const Hash = struct { |
| 134 | } | 133 | } |
| 135 | } | 134 | } |
| 136 | | 135 | |
| | 136 | pub const digest_length = 32; |
| | 137 | |
| 137 | /// Finish the current hashing operation, writing the hash to `out` | 138 | /// Finish the current hashing operation, writing the hash to `out` |
| 138 | /// | 139 | /// |
| 139 | /// From 4.9 "Application to hashing" | 140 | /// From 4.9 "Application to hashing" |
| ... | @@ -166,3 +167,222 @@ test "hash" { | ... | @@ -166,3 +167,222 @@ test "hash" { |
| 166 | hash(&md, &msg); | 167 | hash(&md, &msg); |
| 167 | htest.assertEqual("1C9A03DC6A5DDC5444CFC6F4B154CFF5CF081633B2CEA4D7D0AE7CCFED5AAA44", &md); | 168 | htest.assertEqual("1C9A03DC6A5DDC5444CFC6F4B154CFF5CF081633B2CEA4D7D0AE7CCFED5AAA44", &md); |
| 168 | } | 169 | } |
| | 170 | |
| | 171 | pub const Aead = struct { |
| | 172 | /// ad: Associated Data |
| | 173 | /// npub: public nonce |
| | 174 | /// k: private key |
| | 175 | fn init(ad: []const u8, npub: [16]u8, k: [32]u8) State { |
| | 176 | var state = State{ |
| | 177 | .data = undefined, |
| | 178 | }; |
| | 179 | const buf = state.toSlice(); |
| | 180 | |
| | 181 | // Gimli-Cipher initializes a 48-byte Gimli state to a 16-byte nonce |
| | 182 | // followed by a 32-byte key. |
| | 183 | assert(npub.len + k.len == State.BLOCKBYTES); |
| | 184 | std.mem.copy(u8, buf[0..npub.len], &npub); |
| | 185 | std.mem.copy(u8, buf[npub.len .. npub.len + k.len], &k); |
| | 186 | |
| | 187 | // It then applies the Gimli permutation. |
| | 188 | state.permute(); |
| | 189 | |
| | 190 | { |
| | 191 | // Gimli-Cipher then handles each block of associated data, including |
| | 192 | // exactly one final non-full block, in the same way as Gimli-Hash. |
| | 193 | var data = ad; |
| | 194 | while (data.len >= State.RATE) : (data = data[State.RATE..]) { |
| | 195 | for (buf[0..State.RATE]) |*p, i| { |
| | 196 | p.* ^= data[i]; |
| | 197 | } |
| | 198 | state.permute(); |
| | 199 | } |
| | 200 | for (buf[0..data.len]) |*p, i| { |
| | 201 | p.* ^= data[i]; |
| | 202 | } |
| | 203 | |
| | 204 | // XOR 1 into the next byte of the state |
| | 205 | buf[data.len] ^= 1; |
| | 206 | // XOR 1 into the last byte of the state, position 47. |
| | 207 | buf[buf.len - 1] ^= 1; |
| | 208 | |
| | 209 | state.permute(); |
| | 210 | } |
| | 211 | |
| | 212 | return state; |
| | 213 | } |
| | 214 | |
| | 215 | /// c: ciphertext: output buffer should be of size m.len |
| | 216 | /// at: authentication tag: output MAC |
| | 217 | /// m: message |
| | 218 | /// ad: Associated Data |
| | 219 | /// npub: public nonce |
| | 220 | /// k: private key |
| | 221 | pub fn encrypt(c: []u8, at: *[State.RATE]u8, m: []const u8, ad: []const u8, npub: [16]u8, k: [32]u8) void { |
| | 222 | assert(c.len == m.len); |
| | 223 | |
| | 224 | var state = Aead.init(ad, npub, k); |
| | 225 | const buf = state.toSlice(); |
| | 226 | |
| | 227 | // Gimli-Cipher then handles each block of plaintext, including |
| | 228 | // exactly one final non-full block, in the same way as Gimli-Hash. |
| | 229 | // Whenever a plaintext byte is XORed into a state byte, the new state |
| | 230 | // byte is output as ciphertext. |
| | 231 | var in = m; |
| | 232 | var out = c; |
| | 233 | while (in.len >= State.RATE) : ({ |
| | 234 | in = in[State.RATE..]; |
| | 235 | out = out[State.RATE..]; |
| | 236 | }) { |
| | 237 | for (buf[0..State.RATE]) |*p, i| { |
| | 238 | p.* ^= in[i]; |
| | 239 | out[i] = p.*; |
| | 240 | } |
| | 241 | state.permute(); |
| | 242 | } |
| | 243 | for (buf[0..in.len]) |*p, i| { |
| | 244 | p.* ^= in[i]; |
| | 245 | out[i] = p.*; |
| | 246 | } |
| | 247 | |
| | 248 | // XOR 1 into the next byte of the state |
| | 249 | buf[in.len] ^= 1; |
| | 250 | // XOR 1 into the last byte of the state, position 47. |
| | 251 | buf[buf.len - 1] ^= 1; |
| | 252 | |
| | 253 | state.permute(); |
| | 254 | |
| | 255 | // After the final non-full block of plaintext, the first 16 bytes |
| | 256 | // of the state are output as an authentication tag. |
| | 257 | std.mem.copy(u8, at, buf[0..State.RATE]); |
| | 258 | } |
| | 259 | |
| | 260 | /// m: message: output buffer should be of size c.len |
| | 261 | /// c: ciphertext |
| | 262 | /// at: authentication tag |
| | 263 | /// ad: Associated Data |
| | 264 | /// npub: public nonce |
| | 265 | /// k: private key |
| | 266 | /// NOTE: the check of the authentication tag is currently not done in constant time |
| | 267 | pub fn decrypt(m: []u8, c: []const u8, at: [State.RATE]u8, ad: []u8, npub: [16]u8, k: [32]u8) !void { |
| | 268 | assert(c.len == m.len); |
| | 269 | |
| | 270 | var state = Aead.init(ad, npub, k); |
| | 271 | const buf = state.toSlice(); |
| | 272 | |
| | 273 | var in = c; |
| | 274 | var out = m; |
| | 275 | while (in.len >= State.RATE) : ({ |
| | 276 | in = in[State.RATE..]; |
| | 277 | out = out[State.RATE..]; |
| | 278 | }) { |
| | 279 | for (buf[0..State.RATE]) |*p, i| { |
| | 280 | out[i] = p.* ^ in[i]; |
| | 281 | p.* = in[i]; |
| | 282 | } |
| | 283 | state.permute(); |
| | 284 | } |
| | 285 | for (buf[0..in.len]) |*p, i| { |
| | 286 | out[i] = p.* ^ in[i]; |
| | 287 | p.* = in[i]; |
| | 288 | } |
| | 289 | |
| | 290 | // XOR 1 into the next byte of the state |
| | 291 | buf[in.len] ^= 1; |
| | 292 | // XOR 1 into the last byte of the state, position 47. |
| | 293 | buf[buf.len - 1] ^= 1; |
| | 294 | |
| | 295 | state.permute(); |
| | 296 | |
| | 297 | // After the final non-full block of plaintext, the first 16 bytes |
| | 298 | // of the state are the authentication tag. |
| | 299 | // TODO: use a constant-time equality check here, see https://github.com/ziglang/zig/issues/1776 |
| | 300 | if (!mem.eql(u8, buf[0..State.RATE], &at)) { |
| | 301 | @memset(m.ptr, undefined, m.len); |
| | 302 | return error.InvalidMessage; |
| | 303 | } |
| | 304 | } |
| | 305 | }; |
| | 306 | |
| | 307 | test "cipher" { |
| | 308 | var key: [32]u8 = undefined; |
| | 309 | try std.fmt.hexToBytes(&key, "000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F"); |
| | 310 | var nonce: [16]u8 = undefined; |
| | 311 | try std.fmt.hexToBytes(&nonce, "000102030405060708090A0B0C0D0E0F"); |
| | 312 | { // test vector (1) from NIST KAT submission. |
| | 313 | const ad: [0]u8 = undefined; |
| | 314 | const pt: [0]u8 = undefined; |
| | 315 | |
| | 316 | var ct: [pt.len]u8 = undefined; |
| | 317 | var at: [16]u8 = undefined; |
| | 318 | Aead.encrypt(&ct, &at, &pt, &ad, nonce, key); |
| | 319 | htest.assertEqual("", &ct); |
| | 320 | htest.assertEqual("14DA9BB7120BF58B985A8E00FDEBA15B", &at); |
| | 321 | |
| | 322 | var pt2: [pt.len]u8 = undefined; |
| | 323 | try Aead.decrypt(&pt2, &ct, at, &ad, nonce, key); |
| | 324 | testing.expectEqualSlices(u8, &pt, &pt2); |
| | 325 | } |
| | 326 | { // test vector (34) from NIST KAT submission. |
| | 327 | const ad: [0]u8 = undefined; |
| | 328 | var pt: [2 / 2]u8 = undefined; |
| | 329 | try std.fmt.hexToBytes(&pt, "00"); |
| | 330 | |
| | 331 | var ct: [pt.len]u8 = undefined; |
| | 332 | var at: [16]u8 = undefined; |
| | 333 | Aead.encrypt(&ct, &at, &pt, &ad, nonce, key); |
| | 334 | htest.assertEqual("7F", &ct); |
| | 335 | htest.assertEqual("80492C317B1CD58A1EDC3A0D3E9876FC", &at); |
| | 336 | |
| | 337 | var pt2: [pt.len]u8 = undefined; |
| | 338 | try Aead.decrypt(&pt2, &ct, at, &ad, nonce, key); |
| | 339 | testing.expectEqualSlices(u8, &pt, &pt2); |
| | 340 | } |
| | 341 | { // test vector (106) from NIST KAT submission. |
| | 342 | var ad: [12 / 2]u8 = undefined; |
| | 343 | try std.fmt.hexToBytes(&ad, "000102030405"); |
| | 344 | var pt: [6 / 2]u8 = undefined; |
| | 345 | try std.fmt.hexToBytes(&pt, "000102"); |
| | 346 | |
| | 347 | var ct: [pt.len]u8 = undefined; |
| | 348 | var at: [16]u8 = undefined; |
| | 349 | Aead.encrypt(&ct, &at, &pt, &ad, nonce, key); |
| | 350 | htest.assertEqual("484D35", &ct); |
| | 351 | htest.assertEqual("030BBEA23B61C00CED60A923BDCF9147", &at); |
| | 352 | |
| | 353 | var pt2: [pt.len]u8 = undefined; |
| | 354 | try Aead.decrypt(&pt2, &ct, at, &ad, nonce, key); |
| | 355 | testing.expectEqualSlices(u8, &pt, &pt2); |
| | 356 | } |
| | 357 | { // test vector (790) from NIST KAT submission. |
| | 358 | var ad: [60 / 2]u8 = undefined; |
| | 359 | try std.fmt.hexToBytes(&ad, "000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D"); |
| | 360 | var pt: [46 / 2]u8 = undefined; |
| | 361 | try std.fmt.hexToBytes(&pt, "000102030405060708090A0B0C0D0E0F10111213141516"); |
| | 362 | |
| | 363 | var ct: [pt.len]u8 = undefined; |
| | 364 | var at: [16]u8 = undefined; |
| | 365 | Aead.encrypt(&ct, &at, &pt, &ad, nonce, key); |
| | 366 | htest.assertEqual("6815B4A0ECDAD01596EAD87D9E690697475D234C6A13D1", &ct); |
| | 367 | htest.assertEqual("DFE23F1642508290D68245279558B2FB", &at); |
| | 368 | |
| | 369 | var pt2: [pt.len]u8 = undefined; |
| | 370 | try Aead.decrypt(&pt2, &ct, at, &ad, nonce, key); |
| | 371 | testing.expectEqualSlices(u8, &pt, &pt2); |
| | 372 | } |
| | 373 | { // test vector (1057) from NIST KAT submission. |
| | 374 | const ad: [0]u8 = undefined; |
| | 375 | var pt: [64 / 2]u8 = undefined; |
| | 376 | try std.fmt.hexToBytes(&pt, "000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F"); |
| | 377 | |
| | 378 | var ct: [pt.len]u8 = undefined; |
| | 379 | var at: [16]u8 = undefined; |
| | 380 | Aead.encrypt(&ct, &at, &pt, &ad, nonce, key); |
| | 381 | htest.assertEqual("7F8A2CF4F52AA4D6B2E74105C30A2777B9D0C8AEFDD555DE35861BD3011F652F", &ct); |
| | 382 | htest.assertEqual("7256456FA935AC34BBF55AE135F33257", &at); |
| | 383 | |
| | 384 | var pt2: [pt.len]u8 = undefined; |
| | 385 | try Aead.decrypt(&pt2, &ct, at, &ad, nonce, key); |
| | 386 | testing.expectEqualSlices(u8, &pt, &pt2); |
| | 387 | } |
| | 388 | } |