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comparison genrsa.c @ 910:89555751c489 asm

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merge up to 2013.63, improve ASM makefile rules a bit
author Matt Johnston <matt@ucc.asn.au>
date Thu, 27 Feb 2014 21:35:58 +0800
parents ae766a2c8fa7
children 750ec4ec4cbe
comparison
equal deleted inserted replaced
909:e4b75744acab 910:89555751c489
23 * SOFTWARE. */ 23 * SOFTWARE. */
24 24
25 #include "includes.h" 25 #include "includes.h"
26 #include "dbutil.h" 26 #include "dbutil.h"
27 #include "bignum.h" 27 #include "bignum.h"
28 #include "random.h" 28 #include "dbrandom.h"
29 #include "rsa.h" 29 #include "rsa.h"
30 #include "genrsa.h" 30 #include "genrsa.h"
31 31
32 #define RSA_E 65537 32 #define RSA_E 65537
33 33
34 #ifdef DROPBEAR_RSA 34 #ifdef DROPBEAR_RSA
35 35
36 static void getrsaprime(mp_int* prime, mp_int *primeminus, 36 static void getrsaprime(mp_int* prime, mp_int *primeminus,
37 mp_int* rsa_e, unsigned int size); 37 mp_int* rsa_e, unsigned int size_bytes);
38 38
39 /* mostly taken from libtomcrypt's rsa key generation routine */ 39 /* mostly taken from libtomcrypt's rsa key generation routine */
40 dropbear_rsa_key * gen_rsa_priv_key(unsigned int size) { 40 dropbear_rsa_key * gen_rsa_priv_key(unsigned int size) {
41 41
42 dropbear_rsa_key * key; 42 dropbear_rsa_key * key;
43 DEF_MP_INT(pminus); 43 DEF_MP_INT(pminus);
44 DEF_MP_INT(qminus); 44 DEF_MP_INT(qminus);
45 DEF_MP_INT(lcm); 45 DEF_MP_INT(lcm);
46 46
47 if (size < 512 || size > 4096 || (size % 8 != 0)) {
48 dropbear_exit("Bits must satisfy 512 <= bits <= 4096, and be a"
49 " multiple of 8");
50 }
51
47 key = m_malloc(sizeof(*key)); 52 key = m_malloc(sizeof(*key));
48 53 m_mp_alloc_init_multi(&key->e, &key->n, &key->d, &key->p, &key->q, NULL);
49 key->e = (mp_int*)m_malloc(sizeof(mp_int)); 54 m_mp_init_multi(&pminus, &lcm, &qminus, NULL);
50 key->n = (mp_int*)m_malloc(sizeof(mp_int));
51 key->d = (mp_int*)m_malloc(sizeof(mp_int));
52 key->p = (mp_int*)m_malloc(sizeof(mp_int));
53 key->q = (mp_int*)m_malloc(sizeof(mp_int));
54
55 m_mp_init_multi(key->e, key->n, key->d, key->p, key->q,
56 &pminus, &lcm, &qminus, NULL);
57
58 seedrandom();
59 55
60 if (mp_set_int(key->e, RSA_E) != MP_OKAY) { 56 if (mp_set_int(key->e, RSA_E) != MP_OKAY) {
61 fprintf(stderr, "RSA generation failed\n"); 57 fprintf(stderr, "RSA generation failed\n");
62 exit(1); 58 exit(1);
63 } 59 }
64 60
65 getrsaprime(key->p, &pminus, key->e, size/2); 61 while (1) {
66 getrsaprime(key->q, &qminus, key->e, size/2); 62 getrsaprime(key->p, &pminus, key->e, size/16);
63 getrsaprime(key->q, &qminus, key->e, size/16);
67 64
68 if (mp_mul(key->p, key->q, key->n) != MP_OKAY) { 65 if (mp_mul(key->p, key->q, key->n) != MP_OKAY) {
69 fprintf(stderr, "RSA generation failed\n"); 66 fprintf(stderr, "RSA generation failed\n");
70 exit(1); 67 exit(1);
68 }
69
70 if ((unsigned int)mp_count_bits(key->n) == size) {
71 break;
72 }
71 } 73 }
72 74
73 /* lcm(p-1, q-1) */ 75 /* lcm(p-1, q-1) */
74 if (mp_lcm(&pminus, &qminus, &lcm) != MP_OKAY) { 76 if (mp_lcm(&pminus, &qminus, &lcm) != MP_OKAY) {
75 fprintf(stderr, "RSA generation failed\n"); 77 fprintf(stderr, "RSA generation failed\n");
88 return key; 90 return key;
89 } 91 }
90 92
91 /* return a prime suitable for p or q */ 93 /* return a prime suitable for p or q */
92 static void getrsaprime(mp_int* prime, mp_int *primeminus, 94 static void getrsaprime(mp_int* prime, mp_int *primeminus,
93 mp_int* rsa_e, unsigned int size) { 95 mp_int* rsa_e, unsigned int size_bytes) {
94 96
95 unsigned char *buf; 97 unsigned char *buf;
96 DEF_MP_INT(temp_gcd); 98 DEF_MP_INT(temp_gcd);
97 99
98 buf = (unsigned char*)m_malloc(size+1); 100 buf = (unsigned char*)m_malloc(size_bytes);
99 101
100 m_mp_init(&temp_gcd); 102 m_mp_init(&temp_gcd);
101 do { 103 do {
102 /* generate a random odd number with MSB set, then find the 104 /* generate a random odd number with MSB set, then find the
103 the next prime above it */ 105 the next prime above it */
104 genrandom(buf, size+1); 106 genrandom(buf, size_bytes);
105 buf[0] |= 0x80; /* MSB set */ 107 buf[0] |= 0x80;
106 108
107 bytes_to_mp(prime, buf, size+1); 109 bytes_to_mp(prime, buf, size_bytes);
108 110
109 /* find the next integer which is prime, 8 round of miller-rabin */ 111 /* find the next integer which is prime, 8 round of miller-rabin */
110 if (mp_prime_next_prime(prime, 8, 0) != MP_OKAY) { 112 if (mp_prime_next_prime(prime, 8, 0) != MP_OKAY) {
111 fprintf(stderr, "RSA generation failed\n"); 113 fprintf(stderr, "RSA generation failed\n");
112 exit(1); 114 exit(1);
124 } 126 }
125 } while (mp_cmp_d(&temp_gcd, 1) != MP_EQ); /* while gcd(p-1, e) != 1 */ 127 } while (mp_cmp_d(&temp_gcd, 1) != MP_EQ); /* while gcd(p-1, e) != 1 */
126 128
127 /* now we have a good value for result */ 129 /* now we have a good value for result */
128 mp_clear(&temp_gcd); 130 mp_clear(&temp_gcd);
129 m_burn(buf, size+1); 131 m_burn(buf, size_bytes);
130 m_free(buf); 132 m_free(buf);
131 } 133 }
132 134
133 #endif /* DROPBEAR_RSA */ 135 #endif /* DROPBEAR_RSA */