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authorUros Majstorovic <majstor@majstor.org>2022-02-02 06:25:38 +0100
committerUros Majstorovic <majstor@majstor.org>2022-02-02 06:25:38 +0100
commit378d4ce7552df580e3ddd89c2faa9f8c5086d646 (patch)
tree36fe323de93de5d6b8fb27827fc57984c5b15f6d /ext/libressl/crypto/poly1305/poly1305-donna.c
parent9d775a05562d6166a5142d9820ffa7c26de55d6c (diff)
renamed crypto -> ext
Diffstat (limited to 'ext/libressl/crypto/poly1305/poly1305-donna.c')
-rw-r--r--ext/libressl/crypto/poly1305/poly1305-donna.c321
1 files changed, 321 insertions, 0 deletions
diff --git a/ext/libressl/crypto/poly1305/poly1305-donna.c b/ext/libressl/crypto/poly1305/poly1305-donna.c
new file mode 100644
index 0000000..773ea4e
--- /dev/null
+++ b/ext/libressl/crypto/poly1305/poly1305-donna.c
@@ -0,0 +1,321 @@
+/* $OpenBSD: poly1305-donna.c,v 1.3 2014/06/12 15:49:30 deraadt Exp $ */
+/*
+ * 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 <stddef.h>
+
+static inline void poly1305_init(poly1305_context *ctx,
+ const unsigned char key[32]);
+static inline void poly1305_update(poly1305_context *ctx,
+ const unsigned char *m, size_t bytes);
+static inline void poly1305_finish(poly1305_context *ctx,
+ unsigned char mac[16]);
+
+/*
+ * poly1305 implementation using 32 bit * 32 bit = 64 bit multiplication
+ * and 64 bit addition.
+ */
+
+#define poly1305_block_size 16
+
+/* 17 + sizeof(size_t) + 14*sizeof(unsigned long) */
+typedef struct poly1305_state_internal_t {
+ 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_internal_t;
+
+/* interpret four 8 bit unsigned integers as a 32 bit unsigned integer in little endian */
+static unsigned long
+U8TO32(const unsigned char *p)
+{
+ return (((unsigned long)(p[0] & 0xff)) |
+ ((unsigned long)(p[1] & 0xff) << 8) |
+ ((unsigned long)(p[2] & 0xff) << 16) |
+ ((unsigned long)(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;
+}
+
+static inline void
+poly1305_init(poly1305_context *ctx, const unsigned char key[32])
+{
+ poly1305_state_internal_t *st = (poly1305_state_internal_t *)ctx;
+
+ /* 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_internal_t *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;
+}
+
+static inline void
+poly1305_update(poly1305_context *ctx, const unsigned char *m, size_t bytes)
+{
+ poly1305_state_internal_t *st = (poly1305_state_internal_t *)ctx;
+ 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;
+ }
+}
+
+static inline void
+poly1305_finish(poly1305_context *ctx, unsigned char mac[16])
+{
+ poly1305_state_internal_t *st = (poly1305_state_internal_t *)ctx;
+ 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;
+}