1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
// SCEkrit.c (v1.0): Compute Sony's Private Keys
// Based on Sven's sceverify.c
// -------------------------------------------------------------
// Compile by copying to fail0verflow's ps3tools and add
// SCEkrit.c to TOOLS in the Makefile.
// Depends on libgmp; add -lgmp to LDFLAGS
// - Aaron Lindsay / @AerialX
// And thanks gbcft!

// Copyright 2010       Sven Peter <[email protected]>
// Licensed under the terms of the GNU GPL, version 2
// http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt

#include "tools.h"
#include "types.h"

#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <stdlib.h>
#include <gmp.h>

static int keyid = -1;

static u8 *ptr1 = NULL;
static u8 *ptr2 = NULL;

static u16 type;
typedef struct {
	u16 flags;
	u32 meta_offset;
	u64 info_offset;
	u32 app_type;
	u64 filesize;
	u64 header_len;
} fileinfo;

static fileinfo info1;
static fileinfo info2;

static struct keylist *klist = NULL;

static struct keylist *self_load_keys(fileinfo* info)
{
	enum sce_key id;

	switch (info->app_type) {
		case 1:
			id = KEY_LV0;
			break;
	 	case 2:
			id = KEY_LV1;
			break;
		case 3:
			id = KEY_LV2;
			break;
		case 4:	
			id = KEY_APP;
			break;
		case 5:
			id = KEY_ISO;
			break;
		case 6:
			id = KEY_LDR;
			break;
		default:
			fail("invalid type: %08x", info->app_type);	
	}

	return keys_get(id);
}

static void read_self_header(u8* ptr, fileinfo* info)
{
	info->flags    =    be16(ptr + 0x08);
	info->meta_offset = be32(ptr + 0x0c);
	info->header_len =  be64(ptr + 0x10);
	info->filesize =    be64(ptr + 0x18);
	info->info_offset = be64(ptr + 0x28);

	info->app_type =    be32(ptr + info->info_offset + 0x0c);

	klist = self_load_keys(info);
}

static void read_pkg_header(u8* ptr, fileinfo* info)
{
	info->flags    =    be16(ptr + 0x08);
	info->meta_offset = be32(ptr + 0x0c);
	info->header_len =  be64(ptr + 0x10);
	info->filesize =    be64(ptr + 0x18);

	klist = keys_get(KEY_PKG);
}

static void decrypt(u8* ptr)
{
	if (keyid < 0)
		keyid = sce_decrypt_header(ptr, klist);
	else if (keyid != sce_decrypt_header(ptr, klist))
		fail("Both files must have the same key id");

	if (keyid < 0)
		fail("sce_decrypt_header failed");

	if (sce_decrypt_data(ptr) < 0)
		fail("sce_decrypt_data failed");

	if (klist->keys[keyid].pub_avail < 0)
		fail("no public key available");

	if (ecdsa_set_curve(klist->keys[keyid].ctype) < 0)
		fail("ecdsa_set_curve failed");

	ecdsa_set_pub(klist->keys[keyid].pub);
}

static void verify_signature(u8* ptr, fileinfo* info, u8* hash, u8** s, u8** r)
{
	u64 sig_len;

	sig_len = be64(ptr + info->meta_offset + 0x60);
	*r = ptr + sig_len;
	*s = *r + 21;

	sha1(ptr, sig_len, hash);

	printf("Signature\n");
	if (ecdsa_verify(hash, *r, *s))
		printf("  Status: OK\n");
	else
		printf("  Status: FAIL\n");
}

static void load_num(mpz_t n, u8* un)
{
	char buffer[0x100];
	char* ptr = buffer;
	int i;
	for (i = 0; i < 21; i++) {
		sprintf(ptr, "%02x", un[i]);
		ptr += 2;
	}
	mpz_set_str(n, buffer, 16);
}

static char* calculate_private_key(u8* us1, u8* us2, u8* uz1, u8* uz2, u8* un, u8* ur)
{
	mpz_t s1, s2, z1, z2, n, r, k, dA;
	mpz_inits(s1, s2, z1, z2, n, r, k, dA, NULL);
	load_num(s1, us1); load_num(s2, us2); load_num(z1, uz1); load_num(z2, uz2); load_num(n, un); load_num(r, ur);

	mpz_sub(z2, z1, z2);
	mpz_sub(s2, s1, s2);
	mpz_invert(s2, s2, n);
	mpz_mul(k, z2, s2);
	mpz_mod(k, k, n);

	mpz_mul(s2, s1, k);
	mpz_sub(s2, s2, z1);
	mpz_invert(r, r, n);
	mpz_mul(dA, s2, r);
	mpz_mod(dA, dA, n);

//	printf("k: %s\n", mpz_get_str(NULL, 16, k));
	return mpz_get_str(NULL, 16, dA);
}

int main(int argc, char *argv[])
{
	if (argc != 3)
		fail("usage: scesekrit filename1 filename2");

	ptr1 = mmap_file(argv[1]);
	ptr2 = mmap_file(argv[2]);

	type = be16(ptr1 + 0x0a);
	if (type != be16(ptr2 + 0x0a))
		fail("Files must be the same type");
	
	if (type == 1) {
		read_self_header(ptr1, &info1);
	} else if(type == 3) {
		read_pkg_header(ptr1, &info1);
	} else
		fail("Unknown type: %d", type);

	if ((info1.flags) & 0x8000)
		fail("devkit file; nothing to verify");

	if (klist == NULL)
		fail("no key found");

	decrypt(ptr1);
	
	if (type == 1) {
		read_self_header(ptr2, &info2);
	} else if(type == 3) {
		read_pkg_header(ptr2, &info2);
	} else
		fail("Unknown type: %d", type);

	if ((info2.flags) & 0x8000)
		fail("devkit file; nothing to verify");

	if (klist == NULL)
		fail("no key found");

	decrypt(ptr2);

	u8* s1;
	u8* s2;
	u8 z1[21];
	u8 z2[21];
	u8* r1;
	u8* r2;
	u8 ec[21];
	u8 n[21];
	z1[0] = 0;
	z2[0] = 0;
	
	ecdsa_get_params(klist->keys[keyid].ctype, ec, ec, ec, n, ec, ec);

	printf("%s ", argv[1]);
	verify_signature(ptr1, &info1, z1 + 1, &s1, &r1);
	printf("%s ", argv[2]);
	verify_signature(ptr2, &info2, z2 + 1, &s2, &r2);

	if (memcmp(r1, r2, 21))
		fail("Both files must share the same r signature value.");

	const char* dA = calculate_private_key(s1, s2, z1, z2, n, r1);

	int len = strlen(dA);
	int i;
	printf("Private Key: ");
	for (i = len / 2; i < 21; i++)
		printf("00");
	printf("%s\n", dA);

	return 0;
}