1 /******************************************************************************
2 * Filename: sw_poly1305-donna.c
3 ******************************************************************************/
4
5 #include "sw_poly1305-donna.h"
6
7 #include "sw_poly1305-donna-32.h"
8
9 void
poly1305_update(poly1305_context * ctx,const unsigned char * m,size_t bytes)10 poly1305_update(poly1305_context *ctx, const unsigned char *m, size_t bytes) {
11 poly1305_state_internal_t *st = (poly1305_state_internal_t *)ctx;
12 size_t i;
13
14 /* handle leftover */
15 if (st->leftover) {
16 size_t want = (poly1305_block_size - st->leftover);
17 if (want > bytes)
18 want = bytes;
19 for (i = 0; i < want; i++)
20 st->buffer[st->leftover + i] = m[i];
21 bytes -= want;
22 m += want;
23 st->leftover += want;
24 if (st->leftover < poly1305_block_size)
25 return;
26 poly1305_blocks(st, st->buffer, poly1305_block_size);
27 st->leftover = 0;
28 }
29
30 /* process full blocks */
31 if (bytes >= poly1305_block_size) {
32 size_t want = (bytes & ~(poly1305_block_size - 1));
33 poly1305_blocks(st, m, want);
34 m += want;
35 bytes -= want;
36 }
37
38 /* store leftover */
39 if (bytes) {
40 for (i = 0; i < bytes; i++)
41 st->buffer[st->leftover + i] = m[i];
42 st->leftover += bytes;
43 }
44 }
45
46 void
poly1305_auth(unsigned char mac[16],const unsigned char * m,size_t bytes,const unsigned char key[32])47 poly1305_auth(unsigned char mac[16], const unsigned char *m, size_t bytes, const unsigned char key[32]) {
48 poly1305_context ctx;
49 poly1305_init(&ctx, key);
50 poly1305_update(&ctx, m, bytes);
51 poly1305_finish(&ctx, mac);
52 }
53
54 int
poly1305_verify(const unsigned char mac1[16],const unsigned char mac2[16])55 poly1305_verify(const unsigned char mac1[16], const unsigned char mac2[16]) {
56 size_t i;
57 unsigned int dif = 0;
58 for (i = 0; i < 16; i++)
59 dif |= (mac1[i] ^ mac2[i]);
60 dif = (dif - 1) >> ((sizeof(unsigned int) * 8) - 1);
61 return (dif & 1);
62 }
63
64
65 /* test a few basic operations */
66 int
poly1305_power_on_self_test(void)67 poly1305_power_on_self_test(void) {
68 /* example from nacl */
69 static const unsigned char nacl_key[32] = {
70 0xee,0xa6,0xa7,0x25,0x1c,0x1e,0x72,0x91,
71 0x6d,0x11,0xc2,0xcb,0x21,0x4d,0x3c,0x25,
72 0x25,0x39,0x12,0x1d,0x8e,0x23,0x4e,0x65,
73 0x2d,0x65,0x1f,0xa4,0xc8,0xcf,0xf8,0x80
74 };
75
76 static const unsigned char nacl_msg[131] = {
77 0x8e,0x99,0x3b,0x9f,0x48,0x68,0x12,0x73,
78 0xc2,0x96,0x50,0xba,0x32,0xfc,0x76,0xce,
79 0x48,0x33,0x2e,0xa7,0x16,0x4d,0x96,0xa4,
80 0x47,0x6f,0xb8,0xc5,0x31,0xa1,0x18,0x6a,
81 0xc0,0xdf,0xc1,0x7c,0x98,0xdc,0xe8,0x7b,
82 0x4d,0xa7,0xf0,0x11,0xec,0x48,0xc9,0x72,
83 0x71,0xd2,0xc2,0x0f,0x9b,0x92,0x8f,0xe2,
84 0x27,0x0d,0x6f,0xb8,0x63,0xd5,0x17,0x38,
85 0xb4,0x8e,0xee,0xe3,0x14,0xa7,0xcc,0x8a,
86 0xb9,0x32,0x16,0x45,0x48,0xe5,0x26,0xae,
87 0x90,0x22,0x43,0x68,0x51,0x7a,0xcf,0xea,
88 0xbd,0x6b,0xb3,0x73,0x2b,0xc0,0xe9,0xda,
89 0x99,0x83,0x2b,0x61,0xca,0x01,0xb6,0xde,
90 0x56,0x24,0x4a,0x9e,0x88,0xd5,0xf9,0xb3,
91 0x79,0x73,0xf6,0x22,0xa4,0x3d,0x14,0xa6,
92 0x59,0x9b,0x1f,0x65,0x4c,0xb4,0x5a,0x74,
93 0xe3,0x55,0xa5
94 };
95
96 static const unsigned char nacl_mac[16] = {
97 0xf3,0xff,0xc7,0x70,0x3f,0x94,0x00,0xe5,
98 0x2a,0x7d,0xfb,0x4b,0x3d,0x33,0x05,0xd9
99 };
100
101 /* generates a final value of (2^130 - 2) == 3 */
102 static const unsigned char wrap_key[32] = {
103 0x02,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
104 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
105 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
106 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
107 };
108
109 static const unsigned char wrap_msg[16] = {
110 0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,
111 0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff
112 };
113
114 static const unsigned char wrap_mac[16] = {
115 0x03,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
116 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
117 };
118
119 /*
120 mac of the macs of messages of length 0 to 256, where the key and messages
121 have all their values set to the length
122 */
123 static const unsigned char total_key[32] = {
124 0x01,0x02,0x03,0x04,0x05,0x06,0x07,
125 0xff,0xfe,0xfd,0xfc,0xfb,0xfa,0xf9,
126 0xff,0xff,0xff,0xff,0xff,0xff,0xff,
127 0xff,0xff,0xff,0xff,0xff,0xff,0xff
128 };
129
130 static const unsigned char total_mac[16] = {
131 0x64,0xaf,0xe2,0xe8,0xd6,0xad,0x7b,0xbd,
132 0xd2,0x87,0xf9,0x7c,0x44,0x62,0x3d,0x39
133 };
134
135 poly1305_context ctx;
136 poly1305_context total_ctx;
137 unsigned char all_key[32];
138 unsigned char all_msg[256];
139 unsigned char mac[16];
140 size_t i, j;
141 int result = 1;
142
143 for (i = 0; i < sizeof(mac); i++)
144 mac[i] = 0;
145 poly1305_auth(mac, nacl_msg, sizeof(nacl_msg), nacl_key);
146 result &= poly1305_verify(nacl_mac, mac);
147
148 for (i = 0; i < sizeof(mac); i++)
149 mac[i] = 0;
150 poly1305_init(&ctx, nacl_key);
151 poly1305_update(&ctx, nacl_msg + 0, 32);
152 poly1305_update(&ctx, nacl_msg + 32, 64);
153 poly1305_update(&ctx, nacl_msg + 96, 16);
154 poly1305_update(&ctx, nacl_msg + 112, 8);
155 poly1305_update(&ctx, nacl_msg + 120, 4);
156 poly1305_update(&ctx, nacl_msg + 124, 2);
157 poly1305_update(&ctx, nacl_msg + 126, 1);
158 poly1305_update(&ctx, nacl_msg + 127, 1);
159 poly1305_update(&ctx, nacl_msg + 128, 1);
160 poly1305_update(&ctx, nacl_msg + 129, 1);
161 poly1305_update(&ctx, nacl_msg + 130, 1);
162 poly1305_finish(&ctx, mac);
163 result &= poly1305_verify(nacl_mac, mac);
164
165 for (i = 0; i < sizeof(mac); i++)
166 mac[i] = 0;
167 poly1305_auth(mac, wrap_msg, sizeof(wrap_msg), wrap_key);
168 result &= poly1305_verify(wrap_mac, mac);
169
170 poly1305_init(&total_ctx, total_key);
171 for (i = 0; i < 256; i++) {
172 /* set key and message to 'i,i,i..' */
173 for (j = 0; j < sizeof(all_key); j++)
174 all_key[j] = i;
175 for (j = 0; j < i; j++)
176 all_msg[j] = i;
177 poly1305_auth(mac, all_msg, i, all_key);
178 poly1305_update(&total_ctx, mac, 16);
179 }
180 poly1305_finish(&total_ctx, mac);
181 result &= poly1305_verify(total_mac, mac);
182
183 return result;
184 }
185
