diff options
author | Damien Miller <djm@mindrot.org> | 2013-12-07 11:24:01 +1100 |
---|---|---|
committer | Damien Miller <djm@mindrot.org> | 2013-12-07 11:24:01 +1100 |
commit | 5be9d9e3cbd9c66f24745d25bf2e809c1d158ee0 (patch) | |
tree | d2086d37436014ea44f0f024396a1a8638640b00 | |
parent | bcd00abd8451f36142ae2ee10cc657202149201e (diff) |
- markus@cvs.openbsd.org 2013/12/06 13:39:49
[authfd.c authfile.c key.c key.h myproposal.h pathnames.h readconf.c]
[servconf.c ssh-agent.c ssh-keygen.c ssh-keyscan.1 ssh-keyscan.c]
[ssh-keysign.c ssh.c ssh_config.5 sshd.8 sshd.c verify.c ssh-ed25519.c]
[sc25519.h sc25519.c hash.c ge25519_base.data ge25519.h ge25519.c]
[fe25519.h fe25519.c ed25519.c crypto_api.h blocks.c]
support ed25519 keys (hostkeys and user identities) using the public
domain ed25519 reference code from SUPERCOP, see
http://ed25519.cr.yp.to/software.html
feedback, help & ok djm@
-rw-r--r-- | ChangeLog | 10 | ||||
-rw-r--r-- | authfd.c | 4 | ||||
-rw-r--r-- | authfile.c | 10 | ||||
-rw-r--r-- | blocks.c | 243 | ||||
-rw-r--r-- | crypto_api.h | 43 | ||||
-rw-r--r-- | ed25519.c | 139 | ||||
-rw-r--r-- | fe25519.c | 331 | ||||
-rw-r--r-- | fe25519.h | 66 | ||||
-rw-r--r-- | ge25519.c | 315 | ||||
-rw-r--r-- | ge25519.h | 39 | ||||
-rw-r--r-- | ge25519_base.data | 854 | ||||
-rw-r--r-- | hash.c | 74 | ||||
-rw-r--r-- | key.c | 193 | ||||
-rw-r--r-- | key.h | 13 | ||||
-rw-r--r-- | myproposal.h | 4 | ||||
-rw-r--r-- | pathnames.h | 4 | ||||
-rw-r--r-- | readconf.c | 4 | ||||
-rw-r--r-- | sc25519.c | 302 | ||||
-rw-r--r-- | sc25519.h | 76 | ||||
-rw-r--r-- | servconf.c | 4 | ||||
-rw-r--r-- | ssh-agent.c | 3 | ||||
-rw-r--r-- | ssh-ed25519.c | 141 | ||||
-rw-r--r-- | ssh-keygen.c | 11 | ||||
-rw-r--r-- | ssh-keyscan.1 | 5 | ||||
-rw-r--r-- | ssh-keyscan.c | 16 | ||||
-rw-r--r-- | ssh-keysign.c | 5 | ||||
-rw-r--r-- | ssh.c | 17 | ||||
-rw-r--r-- | ssh_config.5 | 6 | ||||
-rw-r--r-- | sshd.8 | 5 | ||||
-rw-r--r-- | sshd.c | 6 | ||||
-rw-r--r-- | verify.c | 44 |
31 files changed, 2932 insertions, 55 deletions
@@ -17,6 +17,16 @@ [ssh-keygen.c PROTOCOL.key] new private key format, bcrypt as KDF by default; details in PROTOCOL.key; feedback and lots help from djm; ok djm@ + - markus@cvs.openbsd.org 2013/12/06 13:39:49 + [authfd.c authfile.c key.c key.h myproposal.h pathnames.h readconf.c] + [servconf.c ssh-agent.c ssh-keygen.c ssh-keyscan.1 ssh-keyscan.c] + [ssh-keysign.c ssh.c ssh_config.5 sshd.8 sshd.c verify.c ssh-ed25519.c] + [sc25519.h sc25519.c hash.c ge25519_base.data ge25519.h ge25519.c] + [fe25519.h fe25519.c ed25519.c crypto_api.h blocks.c] + support ed25519 keys (hostkeys and user identities) using the public + domain ed25519 reference code from SUPERCOP, see + http://ed25519.cr.yp.to/software.html + feedback, help & ok djm@ 20131205 - (djm) OpenBSD CVS Sync @@ -1,4 +1,4 @@ -/* $OpenBSD: authfd.c,v 1.89 2013/12/06 13:30:08 markus Exp $ */ +/* $OpenBSD: authfd.c,v 1.90 2013/12/06 13:39:49 markus Exp $ */ /* * Author: Tatu Ylonen <ylo@cs.hut.fi> * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland @@ -508,6 +508,8 @@ ssh_add_identity_constrained(AuthenticationConnection *auth, Key *key, case KEY_DSA_CERT_V00: case KEY_ECDSA: case KEY_ECDSA_CERT: + case KEY_ED25519: + case KEY_ED25519_CERT: type = constrained ? SSH2_AGENTC_ADD_ID_CONSTRAINED : SSH2_AGENTC_ADD_IDENTITY; @@ -1,4 +1,4 @@ -/* $OpenBSD: authfile.c,v 1.99 2013/12/06 13:34:54 markus Exp $ */ +/* $OpenBSD: authfile.c,v 1.100 2013/12/06 13:39:49 markus Exp $ */ /* * Author: Tatu Ylonen <ylo@cs.hut.fi> * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland @@ -50,6 +50,8 @@ /* compatibility with old or broken OpenSSL versions */ #include "openbsd-compat/openssl-compat.h" +#include "crypto_api.h" + #include <errno.h> #include <fcntl.h> #include <stdarg.h> @@ -593,6 +595,9 @@ key_private_to_blob(Key *key, Buffer *blob, const char *passphrase, comment, new_format_cipher, new_format_rounds); } return key_private_pem_to_blob(key, blob, passphrase, comment); + case KEY_ED25519: + return key_private_to_blob2(key, blob, passphrase, + comment, new_format_cipher, new_format_rounds); default: error("%s: cannot save key type %d", __func__, key->type); return 0; @@ -997,6 +1002,9 @@ key_parse_private_type(Buffer *blob, int type, const char *passphrase, case KEY_DSA: case KEY_ECDSA: case KEY_RSA: + return key_parse_private_pem(blob, type, passphrase, commentp); + case KEY_ED25519: + return key_parse_private2(blob, type, passphrase, commentp); case KEY_UNSPEC: if ((k = key_parse_private2(blob, type, passphrase, commentp))) return k; diff --git a/blocks.c b/blocks.c new file mode 100644 index 00000000..95c57af5 --- /dev/null +++ b/blocks.c @@ -0,0 +1,243 @@ +/* $OpenBSD: */ + +/* Public Domain, from supercop-20130419/crypto_hashblocks/sha512/ref/blocks.c */ + +#include "crypto_api.h" + +typedef unsigned long long uint64; + +static uint64 load_bigendian(const unsigned char *x) +{ + return + (uint64) (x[7]) \ + | (((uint64) (x[6])) << 8) \ + | (((uint64) (x[5])) << 16) \ + | (((uint64) (x[4])) << 24) \ + | (((uint64) (x[3])) << 32) \ + | (((uint64) (x[2])) << 40) \ + | (((uint64) (x[1])) << 48) \ + | (((uint64) (x[0])) << 56) + ; +} + +static void store_bigendian(unsigned char *x,uint64 u) +{ + x[7] = u; u >>= 8; + x[6] = u; u >>= 8; + x[5] = u; u >>= 8; + x[4] = u; u >>= 8; + x[3] = u; u >>= 8; + x[2] = u; u >>= 8; + x[1] = u; u >>= 8; + x[0] = u; +} + +#define SHR(x,c) ((x) >> (c)) +#define ROTR(x,c) (((x) >> (c)) | ((x) << (64 - (c)))) + +#define Ch(x,y,z) ((x & y) ^ (~x & z)) +#define Maj(x,y,z) ((x & y) ^ (x & z) ^ (y & z)) +#define Sigma0(x) (ROTR(x,28) ^ ROTR(x,34) ^ ROTR(x,39)) +#define Sigma1(x) (ROTR(x,14) ^ ROTR(x,18) ^ ROTR(x,41)) +#define sigma0(x) (ROTR(x, 1) ^ ROTR(x, 8) ^ SHR(x,7)) +#define sigma1(x) (ROTR(x,19) ^ ROTR(x,61) ^ SHR(x,6)) + +#define M(w0,w14,w9,w1) w0 = sigma1(w14) + w9 + sigma0(w1) + w0; + +#define EXPAND \ + M(w0 ,w14,w9 ,w1 ) \ + M(w1 ,w15,w10,w2 ) \ + M(w2 ,w0 ,w11,w3 ) \ + M(w3 ,w1 ,w12,w4 ) \ + M(w4 ,w2 ,w13,w5 ) \ + M(w5 ,w3 ,w14,w6 ) \ + M(w6 ,w4 ,w15,w7 ) \ + M(w7 ,w5 ,w0 ,w8 ) \ + M(w8 ,w6 ,w1 ,w9 ) \ + M(w9 ,w7 ,w2 ,w10) \ + M(w10,w8 ,w3 ,w11) \ + M(w11,w9 ,w4 ,w12) \ + M(w12,w10,w5 ,w13) \ + M(w13,w11,w6 ,w14) \ + M(w14,w12,w7 ,w15) \ + M(w15,w13,w8 ,w0 ) + +#define F(w,k) \ + T1 = h + Sigma1(e) + Ch(e,f,g) + k + w; \ + T2 = Sigma0(a) + Maj(a,b,c); \ + h = g; \ + g = f; \ + f = e; \ + e = d + T1; \ + d = c; \ + c = b; \ + b = a; \ + a = T1 + T2; + +int crypto_hashblocks_sha512(unsigned char *statebytes,const unsigned char *in,unsigned long long inlen) +{ + uint64 state[8]; + uint64 a; + uint64 b; + uint64 c; + uint64 d; + uint64 e; + uint64 f; + uint64 g; + uint64 h; + uint64 T1; + uint64 T2; + + a = load_bigendian(statebytes + 0); state[0] = a; + b = load_bigendian(statebytes + 8); state[1] = b; + c = load_bigendian(statebytes + 16); state[2] = c; + d = load_bigendian(statebytes + 24); state[3] = d; + e = load_bigendian(statebytes + 32); state[4] = e; + f = load_bigendian(statebytes + 40); state[5] = f; + g = load_bigendian(statebytes + 48); state[6] = g; + h = load_bigendian(statebytes + 56); state[7] = h; + + while (inlen >= 128) { + uint64 w0 = load_bigendian(in + 0); + uint64 w1 = load_bigendian(in + 8); + uint64 w2 = load_bigendian(in + 16); + uint64 w3 = load_bigendian(in + 24); + uint64 w4 = load_bigendian(in + 32); + uint64 w5 = load_bigendian(in + 40); + uint64 w6 = load_bigendian(in + 48); + uint64 w7 = load_bigendian(in + 56); + uint64 w8 = load_bigendian(in + 64); + uint64 w9 = load_bigendian(in + 72); + uint64 w10 = load_bigendian(in + 80); + uint64 w11 = load_bigendian(in + 88); + uint64 w12 = load_bigendian(in + 96); + uint64 w13 = load_bigendian(in + 104); + uint64 w14 = load_bigendian(in + 112); + uint64 w15 = load_bigendian(in + 120); + + F(w0 ,0x428a2f98d728ae22ULL) + F(w1 ,0x7137449123ef65cdULL) + F(w2 ,0xb5c0fbcfec4d3b2fULL) + F(w3 ,0xe9b5dba58189dbbcULL) + F(w4 ,0x3956c25bf348b538ULL) + F(w5 ,0x59f111f1b605d019ULL) + F(w6 ,0x923f82a4af194f9bULL) + F(w7 ,0xab1c5ed5da6d8118ULL) + F(w8 ,0xd807aa98a3030242ULL) + F(w9 ,0x12835b0145706fbeULL) + F(w10,0x243185be4ee4b28cULL) + F(w11,0x550c7dc3d5ffb4e2ULL) + F(w12,0x72be5d74f27b896fULL) + F(w13,0x80deb1fe3b1696b1ULL) + F(w14,0x9bdc06a725c71235ULL) + F(w15,0xc19bf174cf692694ULL) + + EXPAND + + F(w0 ,0xe49b69c19ef14ad2ULL) + F(w1 ,0xefbe4786384f25e3ULL) + F(w2 ,0x0fc19dc68b8cd5b5ULL) + F(w3 ,0x240ca1cc77ac9c65ULL) + F(w4 ,0x2de92c6f592b0275ULL) + F(w5 ,0x4a7484aa6ea6e483ULL) + F(w6 ,0x5cb0a9dcbd41fbd4ULL) + F(w7 ,0x76f988da831153b5ULL) + F(w8 ,0x983e5152ee66dfabULL) + F(w9 ,0xa831c66d2db43210ULL) + F(w10,0xb00327c898fb213fULL) + F(w11,0xbf597fc7beef0ee4ULL) + F(w12,0xc6e00bf33da88fc2ULL) + F(w13,0xd5a79147930aa725ULL) + F(w14,0x06ca6351e003826fULL) + F(w15,0x142929670a0e6e70ULL) + + EXPAND + + F(w0 ,0x27b70a8546d22ffcULL) + F(w1 ,0x2e1b21385c26c926ULL) + F(w2 ,0x4d2c6dfc5ac42aedULL) + F(w3 ,0x53380d139d95b3dfULL) + F(w4 ,0x650a73548baf63deULL) + F(w5 ,0x766a0abb3c77b2a8ULL) + F(w6 ,0x81c2c92e47edaee6ULL) + F(w7 ,0x92722c851482353bULL) + F(w8 ,0xa2bfe8a14cf10364ULL) + F(w9 ,0xa81a664bbc423001ULL) + F(w10,0xc24b8b70d0f89791ULL) + F(w11,0xc76c51a30654be30ULL) + F(w12,0xd192e819d6ef5218ULL) + F(w13,0xd69906245565a910ULL) + F(w14,0xf40e35855771202aULL) + F(w15,0x106aa07032bbd1b8ULL) + + EXPAND + + F(w0 ,0x19a4c116b8d2d0c8ULL) + F(w1 ,0x1e376c085141ab53ULL) + F(w2 ,0x2748774cdf8eeb99ULL) + F(w3 ,0x34b0bcb5e19b48a8ULL) + F(w4 ,0x391c0cb3c5c95a63ULL) + F(w5 ,0x4ed8aa4ae3418acbULL) + F(w6 ,0x5b9cca4f7763e373ULL) + F(w7 ,0x682e6ff3d6b2b8a3ULL) + F(w8 ,0x748f82ee5defb2fcULL) + F(w9 ,0x78a5636f43172f60ULL) + F(w10,0x84c87814a1f0ab72ULL) + F(w11,0x8cc702081a6439ecULL) + F(w12,0x90befffa23631e28ULL) + F(w13,0xa4506cebde82bde9ULL) + F(w14,0xbef9a3f7b2c67915ULL) + F(w15,0xc67178f2e372532bULL) + + EXPAND + + F(w0 ,0xca273eceea26619cULL) + F(w1 ,0xd186b8c721c0c207ULL) + F(w2 ,0xeada7dd6cde0eb1eULL) + F(w3 ,0xf57d4f7fee6ed178ULL) + F(w4 ,0x06f067aa72176fbaULL) + F(w5 ,0x0a637dc5a2c898a6ULL) + F(w6 ,0x113f9804bef90daeULL) + F(w7 ,0x1b710b35131c471bULL) + F(w8 ,0x28db77f523047d84ULL) + F(w9 ,0x32caab7b40c72493ULL) + F(w10,0x3c9ebe0a15c9bebcULL) + F(w11,0x431d67c49c100d4cULL) + F(w12,0x4cc5d4becb3e42b6ULL) + F(w13,0x597f299cfc657e2aULL) + F(w14,0x5fcb6fab3ad6faecULL) + F(w15,0x6c44198c4a475817ULL) + + a += state[0]; + b += state[1]; + c += state[2]; + d += state[3]; + e += state[4]; + f += state[5]; + g += state[6]; + h += state[7]; + + state[0] = a; + state[1] = b; + state[2] = c; + state[3] = d; + state[4] = e; + state[5] = f; + state[6] = g; + state[7] = h; + + in += 128; + inlen -= 128; + } + + store_bigendian(statebytes + 0,state[0]); + store_bigendian(statebytes + 8,state[1]); + store_bigendian(statebytes + 16,state[2]); + store_bigendian(statebytes + 24,state[3]); + store_bigendian(statebytes + 32,state[4]); + store_bigendian(statebytes + 40,state[5]); + store_bigendian(statebytes + 48,state[6]); + store_bigendian(statebytes + 56,state[7]); + + return inlen; +} diff --git a/crypto_api.h b/crypto_api.h new file mode 100644 index 00000000..633463dc --- /dev/null +++ b/crypto_api.h @@ -0,0 +1,43 @@ +/* $OpenBSD: crypto_api.h,v 1.1 2013/12/06 13:39:49 markus Exp $ */ + +/* Placed in the public domain. */ + +#ifndef crypto_api_h +#define crypto_api_h + +#include <stdint.h> +#include <stdlib.h> + +typedef int32_t crypto_int32; +typedef uint32_t crypto_uint32; + +#define randombytes(buf, buf_len) arc4random_buf((buf), (buf_len)) + +#define crypto_hashblocks_sha512_STATEBYTES 64U +#define crypto_hashblocks_sha512_BLOCKBYTES 128U + +int crypto_hashblocks_sha512(unsigned char *, const unsigned char *, + unsigned long long); + +#define crypto_hash_sha512_BYTES 64U + +int crypto_hash_sha512(unsigned char *, const unsigned char *, + unsigned long long); + +int crypto_verify_32(const unsigned char *, const unsigned char *); + +#define crypto_sign_BYTES crypto_sign_ed25519_BYTES +#define crypto_sign_PUBLICKEYBYTES crypto_sign_ed25519_PUBLICKEYBYTES +#define crypto_sign_SECRETKEYBYTES crypto_sign_ed25519_SECRETKEYBYTES + +#define crypto_sign_ed25519_SECRETKEYBYTES 64U +#define crypto_sign_ed25519_PUBLICKEYBYTES 32U +#define crypto_sign_ed25519_BYTES 64U + +int crypto_sign_ed25519(unsigned char *, unsigned long long *, + const unsigned char *, unsigned long long, const unsigned char *); +int crypto_sign_ed25519_open(unsigned char *, unsigned long long *, + const unsigned char *, unsigned long long, const unsigned char *); +int crypto_sign_ed25519_keypair(unsigned char *, unsigned char *); + +#endif /* crypto_api_h */ diff --git a/ed25519.c b/ed25519.c new file mode 100644 index 00000000..da9673a0 --- /dev/null +++ b/ed25519.c @@ -0,0 +1,139 @@ +/* $OpenBSD: */ + +/* Public Domain, from supercop-20130419/crypto_sign/ed25519/ref/ed25519.c */ + +#include "crypto_api.h" + +#include "ge25519.h" + +static void get_hram(unsigned char *hram, const unsigned char *sm, const unsigned char *pk, unsigned char *playground, unsigned long long smlen) +{ + unsigned long long i; + + for (i = 0;i < 32;++i) playground[i] = sm[i]; + for (i = 32;i < 64;++i) playground[i] = pk[i-32]; + for (i = 64;i < smlen;++i) playground[i] = sm[i]; + + crypto_hash_sha512(hram,playground,smlen); +} + + +int crypto_sign_ed25519_keypair( + unsigned char *pk, + unsigned char *sk + ) +{ + sc25519 scsk; + ge25519 gepk; + unsigned char extsk[64]; + int i; + + randombytes(sk, 32); + crypto_hash_sha512(extsk, sk, 32); + extsk[0] &= 248; + extsk[31] &= 127; + extsk[31] |= 64; + + sc25519_from32bytes(&scsk,extsk); + + ge25519_scalarmult_base(&gepk, &scsk); + ge25519_pack(pk, &gepk); + for(i=0;i<32;i++) + sk[32 + i] = pk[i]; + return 0; +} + +int crypto_sign_ed25519( + unsigned char *sm,unsigned long long *smlen, + const unsigned char *m,unsigned long long mlen, + const unsigned char *sk + ) +{ + sc25519 sck, scs, scsk; + ge25519 ger; + unsigned char r[32]; + unsigned char s[32]; + unsigned char extsk[64]; + unsigned long long i; + unsigned char hmg[crypto_hash_sha512_BYTES]; + unsigned char hram[crypto_hash_sha512_BYTES]; + + crypto_hash_sha512(extsk, sk, 32); + extsk[0] &= 248; + extsk[31] &= 127; + extsk[31] |= 64; + + *smlen = mlen+64; + for(i=0;i<mlen;i++) + sm[64 + i] = m[i]; + for(i=0;i<32;i++) + sm[32 + i] = extsk[32+i]; + + crypto_hash_sha512(hmg, sm+32, mlen+32); /* Generate k as h(extsk[32],...,extsk[63],m) */ + + /* Computation of R */ + sc25519_from64bytes(&sck, hmg); + ge25519_scalarmult_base(&ger, &sck); + ge25519_pack(r, &ger); + + /* Computation of s */ + for(i=0;i<32;i++) + sm[i] = r[i]; + + get_hram(hram, sm, sk+32, sm, mlen+64); + + sc25519_from64bytes(&scs, hram); + sc25519_from32bytes(&scsk, extsk); + sc25519_mul(&scs, &scs, &scsk); + + sc25519_add(&scs, &scs, &sck); + + sc25519_to32bytes(s,&scs); /* cat s */ + for(i=0;i<32;i++) + sm[32 + i] = s[i]; + + return 0; +} + +int crypto_sign_ed25519_open( + unsigned char *m,unsigned long long *mlen, + const unsigned char *sm,unsigned long long smlen, + const unsigned char *pk + ) +{ + unsigned int i; + int ret; + unsigned char t2[32]; + ge25519 get1, get2; + sc25519 schram, scs; + unsigned char hram[crypto_hash_sha512_BYTES]; + + *mlen = (unsigned long long) -1; + if (smlen < 64) return -1; + + if (ge25519_unpackneg_vartime(&get1, pk)) return -1; + + get_hram(hram,sm,pk,m,smlen); + + sc25519_from64bytes(&schram, hram); + + sc25519_from32bytes(&scs, sm+32); + + ge25519_double_scalarmult_vartime(&get2, &get1, &schram, &ge25519_base, &scs); + ge25519_pack(t2, &get2); + + ret = crypto_verify_32(sm, t2); + + if (!ret) + { + for(i=0;i<smlen-64;i++) + m[i] = sm[i + 64]; + *mlen = smlen-64; + } + else + { + for(i=0;i<smlen-64;i++) + m[i] = 0; + } + return ret; +} diff --git a/fe25519.c b/fe25519.c new file mode 100644 index 00000000..d2efa505 --- /dev/null +++ b/fe25519.c @@ -0,0 +1,331 @@ +/* $OpenBSD: */ + +/* Public Domain, from supercop-20130419/crypto_sign/ed25519/ref/fe25519.c */ + +#define WINDOWSIZE 1 /* Should be 1,2, or 4 */ +#define WINDOWMASK ((1<<WINDOWSIZE)-1) + +#include "fe25519.h" + +static crypto_uint32 equal(crypto_uint32 a,crypto_uint32 b) /* 16-bit inputs */ +{ + crypto_uint32 x = a ^ b; /* 0: yes; 1..65535: no */ + x -= 1; /* 4294967295: yes; 0..65534: no */ + x >>= 31; /* 1: yes; 0: no */ + return x; +} + +static crypto_uint32 ge(crypto_uint32 a,crypto_uint32 b) /* 16-bit inputs */ +{ + unsigned int x = a; + x -= (unsigned int) b; /* 0..65535: yes; 4294901761..4294967295: no */ + x >>= 31; /* 0: yes; 1: no */ + x ^= 1; /* 1: yes; 0: no */ + return x; +} + +static crypto_uint32 times19(crypto_uint32 a) +{ + return (a << 4) + (a << 1) + a; +} + +static crypto_uint32 times38(crypto_uint32 a) +{ + return (a << 5) + (a << 2) + (a << 1); +} + +static void reduce_add_sub(fe25519 *r) +{ + crypto_uint32 t; + int i,rep; + + for(rep=0;rep<4;rep++) + { + t = r->v[31] >> 7; + r->v[31] &= 127; + t = times19(t); + r->v[0] += t; + for(i=0;i<31;i++) + { + t = r->v[i] >> 8; + r->v[i+1] += t; + r->v[i] &= 255; + } + } +} + +static void reduce_mul(fe25519 *r) +{ + crypto_uint32 t; + int i,rep; + + for(rep=0;rep<2;rep++) + { + t = r->v[31] >> 7; + r->v[31] &= 127; + t = times19(t); + r->v[0] += t; + for(i=0;i<31;i++) + { + t = r->v[i] >> 8; + r->v[i+1] += t; + r->v[i] &= 255; + } + } +} + +/* reduction modulo 2^255-19 */ +void fe25519_freeze(fe25519 *r) +{ + int i; + crypto_uint32 m = equal(r->v[31],127); + for(i=30;i>0;i--) + m &= equal(r->v[i],255); + m &= ge(r->v[0],237); + + m = -m; + + r->v[31] -= m&127; + for(i=30;i>0;i--) + r->v[i] -= m&255; + r->v[0] -= m&237; +} + +void fe25519_unpack(fe25519 *r, const unsigned char x[32]) +{ + int i; + for(i=0;i<32;i++) r->v[i] = x[i]; + r->v[31] &= 127; +} + +/* Assumes input x being reduced below 2^255 */ +void fe25519_pack(unsigned char r[32], const fe25519 *x) +{ + int i; + fe25519 y = *x; + fe25519_freeze(&y); + for(i=0;i<32;i++) + r[i] = y.v[i]; +} + +int fe25519_iszero(const fe25519 *x) +{ + int i; + int r; + fe25519 t = *x; + fe25519_freeze(&t); + r = equal(t.v[0],0); + for(i=1;i<32;i++) + r &= equal(t.v[i],0); + return r; +} + +int fe25519_iseq_vartime(const fe25519 *x, const fe25519 *y) +{ + int i; + fe25519 t1 = *x; + fe25519 t2 = *y; + fe25519_freeze(&t1); + fe25519_freeze(&t2); + for(i=0;i<32;i++) + if(t1.v[i] != t2.v[i]) return 0; + return 1; +} + +void fe25519_cmov(fe25519 *r, const fe25519 *x, unsigned char b) +{ + int i; + crypto_uint32 mask = b; + mask = -mask; + for(i=0;i<32;i++) r->v[i] ^= mask & (x->v[i] ^ r->v[i]); +} + +unsigned char fe25519_getparity(const fe25519 *x) +{ + fe25519 t = *x; + fe25519_freeze(&t); + return t.v[0] & 1; +} + +void fe25519_setone(fe25519 *r) +{ + int i; + r->v[0] = 1; + for(i=1;i<32;i++) r->v[i]=0; +} + +void fe25519_setzero(fe25519 *r) +{ + int i; + for(i=0;i<32;i++) r->v[i]=0; +} + +void fe25519_neg(fe25519 *r, const fe25519 *x) +{ + fe25519 t; + int i; + for(i=0;i<32;i++) t.v[i]=x->v[i]; + fe25519_setzero(r); + fe25519_sub(r, r, &t); +} + +void fe25519_add(fe25519 *r, const fe25519 *x, const fe25519 *y) +{ + int i; + for(i=0;i<32;i++) r->v[i] = x->v[i] + y->v[i]; + reduce_add_sub(r); +} + +void fe25519_sub(fe25519 *r, const fe25519 *x, const fe25519 *y) +{ + int i; + crypto_uint32 t[32]; + t[0] = x->v[0] + 0x1da; + t[31] = x->v[31] + 0xfe; + for(i=1;i<31;i++) t[i] = x->v[i] + 0x1fe; + for(i=0;i<32;i++) r->v[i] = t[i] - y->v[i]; + reduce_add_sub(r); +} + +void fe25519_mul(fe25519 *r, const fe25519 *x, const fe25519 *y) +{ + int i,j; + crypto_uint32 t[63]; + for(i=0;i<63;i++)t[i] = 0; + + for(i=0;i<32;i++) + for(j=0;j<32;j++) + t[i+j] += x->v[i] * y->v[j]; + + for(i=32;i<63;i++) + r->v[i-32] = t[i-32] + times38(t[i]); + r->v[31] = t[31]; /* result now in r[0]...r[31] */ + + reduce_mul(r); +} + +void fe25519_square(fe25519 *r, const fe25519 *x) +{ + fe25519_mul(r, x, x); +} + +void fe25519_invert(fe25519 *r, const fe25519 *x) +{ + fe25519 z2; + fe25519 z9; + fe25519 z11; + fe25519 z2_5_0; + fe25519 z2_10_0; + fe25519 z2_20_0; + fe25519 z2_50_0; + fe25519 z2_100_0; + fe25519 t0; + fe25519 t1; + int i; + + /* 2 */ fe25519_square(&z2,x); + /* 4 */ fe25519_square(&t1,&z2); + /* 8 */ fe25519_square(&t0,&t1); + /* 9 */ fe25519_mul(&z9,&t0,x); + /* 11 */ fe25519_mul(&z11,&z9,&z2); + /* 22 */ fe25519_square(&t0,&z11); + /* 2^5 - 2^0 = 31 */ fe25519_mul(&z2_5_0,&t0,&z9); + + /* 2^6 - 2^1 */ fe25519_square(&t0,&z2_5_0); + /* 2^7 - 2^2 */ fe25519_square(&t1,&t0); + /* 2^8 - 2^3 */ fe25519_square(&t0,&t1); + /* 2^9 - 2^4 */ fe25519_square(&t1,&t0); + /* 2^10 - 2^5 */ fe25519_square(&t0,&t1); + /* 2^10 - 2^0 */ fe25519_mul(&z2_10_0,&t0,&z2_5_0); + + /* 2^11 - 2^1 */ fe25519_square(&t0,&z2_10_0); + /* 2^12 - 2^2 */ fe25519_square(&t1,&t0); + /* 2^20 - 2^10 */ for (i = 2;i < 10;i += 2) { fe25519_square(&t0,&t1); fe25519_square(&t1,&t0); } + /* 2^20 - 2^0 */ fe25519_mul(&z2_20_0,&t1,&z2_10_0); + + /* 2^21 - 2^1 */ fe25519_square(&t0,&z2_20_0); + /* 2^22 - 2^2 */ fe25519_square(&t1,&t0); + /* 2^40 - 2^20 */ for (i = 2;i < 20;i += 2) { fe25519_square(&t0,&t1); fe25519_square(&t1,&t0); } + /* 2^40 - 2^0 */ fe25519_mul(&t0,&t1,&z2_20_0); + + /* 2^41 - 2^1 */ fe25519_square(&t1,&t0); + /* 2^42 - 2^2 */ fe25519_square(&t0,&t1); + /* 2^50 - 2^10 */ for (i = 2;i < 10;i += 2) { fe25519_square(&t1,&t0); fe25519_square(&t0,&t1); } + /* 2^50 - 2^0 */ fe25519_mul(&z2_50_0,&t0,&z2_10_0); + + /* 2^51 - 2^1 */ fe25519_square(&t0,&z2_50_0); + /* 2^52 - 2^2 */ fe25519_square(&t1,&t0); + /* 2^100 - 2^50 */ for (i = 2;i < 50;i += 2) { fe25519_square(&t0,&t1); fe25519_square(&t1,&t0); } + /* 2^100 - 2^0 */ fe25519_mul(&z2_100_0,&t1,&z2_50_0); + + /* 2^101 - 2^1 */ fe25519_square(&t1,&z2_100_0); + /* 2^102 - 2^2 */ fe25519_square(&t0,&t1); + /* 2^200 - 2^100 */ for (i = 2;i < 100;i += 2) { fe25519_square(&t1,&t0); fe25519_square(&t0,&t1); } + /* 2^200 - 2^0 */ fe25519_mul(&t1,&t0,&z2_100_0); + + /* 2^201 - 2^1 */ fe25519_square(&t0,&t1); + /* 2^202 - 2^2 */ fe25519_square(&t1,&t0); + /* 2^250 - 2^50 */ for (i = 2;i < 50;i += 2) { fe25519_square(&t0,&t1); fe25519_square(&t1,&t0); } + /* 2^250 - 2^0 */ fe25519_mul(&t0,&t1,&z2_50_0); + + /* 2^251 - 2^1 */ fe25519_square(&t1,&t0); + /* 2^252 - 2^2 */ fe25519_square(&t0,&t1); + /* 2^253 - 2^3 */ fe25519_square(&t1,&t0); + /* 2^254 - 2^4 */ fe25519_square(&t0,&t1); + /* 2^255 - 2^5 */ fe25519_square(&t1,&t0); + /* 2^255 - 21 */ fe25519_mul(r,&t1,&z11); +} + +void fe25519_pow2523(fe25519 *r, const fe25519 *x) +{ + fe25519 z2; + fe25519 z9; + fe25519 z11; + fe25519 z2_5_0; + fe25519 z2_10_0; + fe25519 z2_20_0; + fe25519 z2_50_0; + fe25519 z2_100_0; + fe25519 t; + int i; + + /* 2 */ fe25519_square(&z2,x); + /* 4 */ fe25519_square(&t,&z2); + /* 8 */ fe25519_square(&t,&t); + /* 9 */ fe25519_mul(&z9,&t,x); + /* 11 */ fe25519_mul(&z11,&z9,&z2); + /* 22 */ fe25519_square(&t,&z11); + /* 2^5 - 2^0 = 31 */ fe25519_mul(&z2_5_0,&t,&z9); + + /* 2^6 - 2^1 */ fe25519_square(&t,&z2_5_0); + /* 2^10 - 2^5 */ for (i = 1;i < 5;i++) { fe25519_square(&t,&t); } + /* 2^10 - 2^0 */ fe25519_mul(&z2_10_0,&t,&z2_5_0); + + /* 2^11 - 2^1 */ fe25519_square(&t,&z2_10_0); + /* 2^20 - 2^10 */ for (i = 1;i < 10;i++) { fe25519_square(&t,&t); } + /* 2^20 - 2^0 */ fe25519_mul(&z2_20_0,&t,&z2_10_0); + + /* 2^21 - 2^1 */ fe25519_square(&t,&z2_20_0); + /* 2^40 - 2^20 */ for (i = 1;i < 20;i++) { fe25519_square(&t,&t); } + /* 2^40 - 2^0 */ fe25519_mul(&t,&t,&z2_20_0); + + /* 2^41 - 2^1 */ fe25519_square(&t,&t); + /* 2^50 - 2^10 */ for (i = 1;i < 10;i++) { fe25519_square(&t,&t); } + /* 2^50 - 2^0 */ fe25519_mul(&z2_50_0,&t,&z2_10_0); + + /* 2^51 - 2^1 */ fe25519_square(&t,&z2_50_0); + /* 2^100 - 2^50 */ for (i = 1;i < 50;i++) { fe25519_square(&t,&t); } + /* 2^100 - 2^0 */ fe25519_mul(&z2_100_0,&t,&z2_50_0); + + /* 2^101 - 2^1 */ fe25519_square(&t,&z2_100_0); + /* 2^200 - 2^100 */ for (i = 1;i < 100;i++) { fe25519_square(&t,&t); } + /* 2^200 - 2^0 */ fe25519_mul(&t,&t,&z2_100_0); + + /* 2^201 - 2^1 */ fe25519_square(&t,&t); + /* 2^250 - 2^50 */ for (i = 1;i < 50;i++) { fe25519_square(&t,&t); } + /* 2^250 - 2^0 */ fe25519_mul(&t,&t,&z2_50_0); + + /* 2^251 - 2^1 */ fe25519_square(&t,&t); + /* 2^252 - 2^2 */ fe25519_square(&t,&t); + /* 2^252 - 3 */ fe25519_mul(r,&t,x); +} diff --git a/fe25519.h b/fe25519.h new file mode 100644 index 00000000..696a67be --- /dev/null +++ b/fe25519.h @@ -0,0 +1,66 @@ +/* $OpenBSD: */ + |