On Mon, Oct 26, 2015 at 18:28 +0100, Mike Belopuhov wrote: > OK? > A few people asked me to use style(9)'ed version from libressl and cut down on my own changes. Here we go with an updated version. This will require an update to the next diff as well.
OK? --- sys/crypto/poly1305.c | 295 ++++++++++++++++++++++++++++++++++++++++++++++++++ sys/crypto/poly1305.h | 26 +++++ 2 files changed, 321 insertions(+) create mode 100644 sys/crypto/poly1305.c create mode 100644 sys/crypto/poly1305.h diff --git sys/crypto/poly1305.c sys/crypto/poly1305.c new file mode 100644 index 0000000..408786f --- /dev/null +++ sys/crypto/poly1305.c @@ -0,0 +1,295 @@ +/* + * Public Domain poly1305 from Andrew Moon + * Based on poly1305-donna.c, poly1305-donna-32.h and poly1305-donna.h from: + * https://github.com/floodyberry/poly1305-donna + */ + +#include <sys/types.h> +#include <sys/systm.h> + +#include "poly1305.h" + +/* interpret four 8 bit unsigned integers as a 32 bit unsigned integer in little endian */ +static unsigned long +U8TO32(const unsigned char *p) +{ + return (((uint32_t)(p[0] & 0xff) ) | + ((uint32_t)(p[1] & 0xff) << 8) | + ((uint32_t)(p[2] & 0xff) << 16) | + ((uint32_t)(p[3] & 0xff) << 24)); +} + +/* store a 32 bit unsigned integer as four 8 bit unsigned integers in little endian */ +static void +U32TO8(unsigned char *p, unsigned long v) +{ + p[0] = (v ) & 0xff; + p[1] = (v >> 8) & 0xff; + p[2] = (v >> 16) & 0xff; + p[3] = (v >> 24) & 0xff; +} + +void +poly1305_init(poly1305_state *st, const unsigned char key[32]) +{ + /* r &= 0xffffffc0ffffffc0ffffffc0fffffff */ + st->r[0] = (U8TO32(&key[ 0]) ) & 0x3ffffff; + st->r[1] = (U8TO32(&key[ 3]) >> 2) & 0x3ffff03; + st->r[2] = (U8TO32(&key[ 6]) >> 4) & 0x3ffc0ff; + st->r[3] = (U8TO32(&key[ 9]) >> 6) & 0x3f03fff; + st->r[4] = (U8TO32(&key[12]) >> 8) & 0x00fffff; + + /* h = 0 */ + st->h[0] = 0; + st->h[1] = 0; + st->h[2] = 0; + st->h[3] = 0; + st->h[4] = 0; + + /* save pad for later */ + st->pad[0] = U8TO32(&key[16]); + st->pad[1] = U8TO32(&key[20]); + st->pad[2] = U8TO32(&key[24]); + st->pad[3] = U8TO32(&key[28]); + + st->leftover = 0; + st->final = 0; +} + +static void +poly1305_blocks(poly1305_state *st, const unsigned char *m, size_t bytes) +{ + const unsigned long hibit = (st->final) ? 0 : (1 << 24); /* 1 << 128 */ + unsigned long r0, r1, r2, r3, r4; + unsigned long s1, s2, s3, s4; + unsigned long h0, h1, h2, h3, h4; + unsigned long long d0, d1, d2, d3, d4; + unsigned long c; + + r0 = st->r[0]; + r1 = st->r[1]; + r2 = st->r[2]; + r3 = st->r[3]; + r4 = st->r[4]; + + s1 = r1 * 5; + s2 = r2 * 5; + s3 = r3 * 5; + s4 = r4 * 5; + + h0 = st->h[0]; + h1 = st->h[1]; + h2 = st->h[2]; + h3 = st->h[3]; + h4 = st->h[4]; + + while (bytes >= poly1305_block_size) { + /* h += m[i] */ + h0 += (U8TO32(m+ 0) ) & 0x3ffffff; + h1 += (U8TO32(m+ 3) >> 2) & 0x3ffffff; + h2 += (U8TO32(m+ 6) >> 4) & 0x3ffffff; + h3 += (U8TO32(m+ 9) >> 6) & 0x3ffffff; + h4 += (U8TO32(m+12) >> 8) | hibit; + + /* h *= r */ + d0 = ((unsigned long long)h0 * r0) + + ((unsigned long long)h1 * s4) + + ((unsigned long long)h2 * s3) + + ((unsigned long long)h3 * s2) + + ((unsigned long long)h4 * s1); + d1 = ((unsigned long long)h0 * r1) + + ((unsigned long long)h1 * r0) + + ((unsigned long long)h2 * s4) + + ((unsigned long long)h3 * s3) + + ((unsigned long long)h4 * s2); + d2 = ((unsigned long long)h0 * r2) + + ((unsigned long long)h1 * r1) + + ((unsigned long long)h2 * r0) + + ((unsigned long long)h3 * s4) + + ((unsigned long long)h4 * s3); + d3 = ((unsigned long long)h0 * r3) + + ((unsigned long long)h1 * r2) + + ((unsigned long long)h2 * r1) + + ((unsigned long long)h3 * r0) + + ((unsigned long long)h4 * s4); + d4 = ((unsigned long long)h0 * r4) + + ((unsigned long long)h1 * r3) + + ((unsigned long long)h2 * r2) + + ((unsigned long long)h3 * r1) + + ((unsigned long long)h4 * r0); + + /* (partial) h %= p */ + c = (unsigned long)(d0 >> 26); + h0 = (unsigned long)d0 & 0x3ffffff; + d1 += c; + c = (unsigned long)(d1 >> 26); + h1 = (unsigned long)d1 & 0x3ffffff; + d2 += c; + c = (unsigned long)(d2 >> 26); + h2 = (unsigned long)d2 & 0x3ffffff; + d3 += c; + c = (unsigned long)(d3 >> 26); + h3 = (unsigned long)d3 & 0x3ffffff; + d4 += c; + c = (unsigned long)(d4 >> 26); + h4 = (unsigned long)d4 & 0x3ffffff; + h0 += c * 5; + c = (h0 >> 26); + h0 = h0 & 0x3ffffff; + h1 += c; + + m += poly1305_block_size; + bytes -= poly1305_block_size; + } + + st->h[0] = h0; + st->h[1] = h1; + st->h[2] = h2; + st->h[3] = h3; + st->h[4] = h4; +} + +void +poly1305_update(poly1305_state *st, const unsigned char *m, size_t bytes) +{ + size_t i; + + /* handle leftover */ + if (st->leftover) { + size_t want = (poly1305_block_size - st->leftover); + if (want > bytes) + want = bytes; + for (i = 0; i < want; i++) + st->buffer[st->leftover + i] = m[i]; + bytes -= want; + m += want; + st->leftover += want; + if (st->leftover < poly1305_block_size) + return; + poly1305_blocks(st, st->buffer, poly1305_block_size); + st->leftover = 0; + } + + /* process full blocks */ + if (bytes >= poly1305_block_size) { + size_t want = (bytes & ~(poly1305_block_size - 1)); + poly1305_blocks(st, m, want); + m += want; + bytes -= want; + } + + /* store leftover */ + if (bytes) { + for (i = 0; i < bytes; i++) + st->buffer[st->leftover + i] = m[i]; + st->leftover += bytes; + } +} + +void +poly1305_finish(poly1305_state *st, unsigned char mac[16]) +{ + unsigned long h0, h1, h2, h3, h4, c; + unsigned long g0, g1, g2, g3, g4; + unsigned long long f; + unsigned long mask; + + /* process the remaining block */ + if (st->leftover) { + size_t i = st->leftover; + st->buffer[i++] = 1; + for (; i < poly1305_block_size; i++) + st->buffer[i] = 0; + st->final = 1; + poly1305_blocks(st, st->buffer, poly1305_block_size); + } + + /* fully carry h */ + h0 = st->h[0]; + h1 = st->h[1]; + h2 = st->h[2]; + h3 = st->h[3]; + h4 = st->h[4]; + + c = h1 >> 26; + h1 = h1 & 0x3ffffff; + h2 += c; + c = h2 >> 26; + h2 = h2 & 0x3ffffff; + h3 += c; + c = h3 >> 26; + h3 = h3 & 0x3ffffff; + h4 += c; + c = h4 >> 26; + h4 = h4 & 0x3ffffff; + h0 += c * 5; + c = h0 >> 26; + h0 = h0 & 0x3ffffff; + h1 += c; + + /* compute h + -p */ + g0 = h0 + 5; + c = g0 >> 26; + g0 &= 0x3ffffff; + g1 = h1 + c; + c = g1 >> 26; + g1 &= 0x3ffffff; + g2 = h2 + c; + c = g2 >> 26; + g2 &= 0x3ffffff; + g3 = h3 + c; + c = g3 >> 26; + g3 &= 0x3ffffff; + g4 = h4 + c - (1 << 26); + + /* select h if h < p, or h + -p if h >= p */ + mask = (g4 >> ((sizeof(unsigned long) * 8) - 1)) - 1; + g0 &= mask; + g1 &= mask; + g2 &= mask; + g3 &= mask; + g4 &= mask; + mask = ~mask; + h0 = (h0 & mask) | g0; + h1 = (h1 & mask) | g1; + h2 = (h2 & mask) | g2; + h3 = (h3 & mask) | g3; + h4 = (h4 & mask) | g4; + + /* h = h % (2^128) */ + h0 = ((h0 ) | (h1 << 26)) & 0xffffffff; + h1 = ((h1 >> 6) | (h2 << 20)) & 0xffffffff; + h2 = ((h2 >> 12) | (h3 << 14)) & 0xffffffff; + h3 = ((h3 >> 18) | (h4 << 8)) & 0xffffffff; + + /* mac = (h + pad) % (2^128) */ + f = (unsigned long long)h0 + st->pad[0]; + h0 = (unsigned long)f; + f = (unsigned long long)h1 + st->pad[1] + (f >> 32); + h1 = (unsigned long)f; + f = (unsigned long long)h2 + st->pad[2] + (f >> 32); + h2 = (unsigned long)f; + f = (unsigned long long)h3 + st->pad[3] + (f >> 32); + h3 = (unsigned long)f; + + U32TO8(mac + 0, h0); + U32TO8(mac + 4, h1); + U32TO8(mac + 8, h2); + U32TO8(mac + 12, h3); + + /* zero out the state */ + st->h[0] = 0; + st->h[1] = 0; + st->h[2] = 0; + st->h[3] = 0; + st->h[4] = 0; + st->r[0] = 0; + st->r[1] = 0; + st->r[2] = 0; + st->r[3] = 0; + st->r[4] = 0; + st->pad[0] = 0; + st->pad[1] = 0; + st->pad[2] = 0; + st->pad[3] = 0; +} diff --git sys/crypto/poly1305.h sys/crypto/poly1305.h new file mode 100644 index 0000000..a36b84a --- /dev/null +++ sys/crypto/poly1305.h @@ -0,0 +1,26 @@ +/* + * Public Domain poly1305 from Andrew Moon + * + * poly1305 implementation using 32 bit * 32 bit = 64 bit multiplication + * and 64 bit addition from https://github.com/floodyberry/poly1305-donna + */ + +#ifndef _POLY1305_H_ +#define _POLY1305_H_ + +#define poly1305_block_size 16 + +typedef struct poly1305_state { + unsigned long r[5]; + unsigned long h[5]; + unsigned long pad[4]; + size_t leftover; + unsigned char buffer[poly1305_block_size]; + unsigned char final; +} poly1305_state; + +void poly1305_init(poly1305_state *, const unsigned char[32]); +void poly1305_update(poly1305_state *, const unsigned char *, size_t); +void poly1305_finish(poly1305_state *, unsigned char[16]); + +#endif /* _POLY1305_H_ */ -- 2.6.2
