hactool/extkeys.c
Michael Scire 2159f4396f Add support for key derivation.
Passing in --sbk=, --tseckey= with -t keygen and an input BOOT0
BIS partition will now derive all keys derivable iwth the sources
in the loaded keyset, and print them to output.
2018-04-26 00:10:14 -06:00

334 lines
13 KiB
C

#include <errno.h>
#include <stdio.h>
#include <string.h>
#include "extkeys.h"
/**
* Reads a line from file f and parses out the key and value from it.
* The format of a line must match /^ *[A-Za-z0-9_] *[,=] *.+$/.
* If a line ends in \r, the final \r is stripped.
* The input file is assumed to have been opened with the 'b' flag.
* The input file is assumed to contain only ASCII.
*
* A line cannot exceed 512 bytes in length.
* Lines that are excessively long will be silently truncated.
*
* On success, *key and *value will be set to point to the key and value in
* the input line, respectively.
* *key and *value may also be NULL in case of empty lines.
* On failure, *key and *value will be set to NULL.
* End of file is considered failure.
*
* Because *key and *value will point to a static buffer, their contents must be
* copied before calling this function again.
* For the same reason, this function is not thread-safe.
*
* The key will be converted to lowercase.
* An empty key is considered a parse error, but an empty value is returned as
* success.
*
* This function assumes that the file can be trusted not to contain any NUL in
* the contents.
*
* Whitespace (' ', ASCII 0x20, as well as '\t', ASCII 0x09) at the beginning of
* the line, at the end of the line as well as around = (or ,) will be ignored.
*
* @param f the file to read
* @param key pointer to change to point to the key
* @param value pointer to change to point to the value
* @return 0 on success,
* 1 on end of file,
* -1 on parse error (line too long, line malformed)
* -2 on I/O error
*/
static int get_kv(FILE *f, char **key, char **value) {
#define SKIP_SPACE(p) do {\
for (; *p == ' ' || *p == '\t'; ++p)\
;\
} while(0);
static char line[512];
char *k, *v, *p, *end;
*key = *value = NULL;
errno = 0;
if (fgets(line, (int)sizeof(line), f) == NULL) {
if (feof(f))
return 1;
else
return -2;
}
if (errno != 0)
return -2;
if (*line == '\n' || *line == '\r' || *line == '\0')
return 0;
/* Not finding \r or \n is not a problem.
* The line might just be exactly 512 characters long, we have no way to
* tell.
* Additionally, it's possible that the last line of a file is not actually
* a line (i.e., does not end in '\n'); we do want to handle those.
*/
if ((p = strchr(line, '\r')) != NULL || (p = strchr(line, '\n')) != NULL) {
end = p;
*p = '\0';
} else {
end = line + strlen(line) + 1;
}
p = line;
SKIP_SPACE(p);
k = p;
/* Validate key and convert to lower case. */
for (; *p != ' ' && *p != ',' && *p != '\t' && *p != '='; ++p) {
if (*p == '\0')
return -1;
if (*p >= 'A' && *p <= 'Z') {
*p = 'a' + (*p - 'A');
continue;
}
if (*p != '_' &&
(*p < '0' && *p > '9') &&
(*p < 'a' && *p > 'z'))
return -1;
}
/* Bail if the final ++p put us at the end of string */
if (*p == '\0')
return -1;
/* We should be at the end of key now and either whitespace or [,=]
* follows.
*/
if (*p == '=' || *p == ',') {
*p++ = '\0';
} else {
*p++ = '\0';
SKIP_SPACE(p);
if (*p != '=' && *p != ',')
return -1;
*p++ = '\0';
}
/* Empty key is an error. */
if (*k == '\0')
return -1;
SKIP_SPACE(p);
v = p;
/* Skip trailing whitespace */
for (p = end - 1; *p == '\t' || *p == ' '; --p)
;
*(p + 1) = '\0';
*key = k;
*value = v;
return 0;
#undef SKIP_SPACE
}
static int ishex(char c) {
if ('a' <= c && c <= 'f') return 1;
if ('A' <= c && c <= 'F') return 1;
if ('0' <= c && c <= '9') return 1;
return 0;
}
static char hextoi(char c) {
if ('a' <= c && c <= 'f') return c - 'a' + 0xA;
if ('A' <= c && c <= 'F') return c - 'A' + 0xA;
if ('0' <= c && c <= '9') return c - '0';
return 0;
}
void parse_hex_key(unsigned char *key, const char *hex, unsigned int len) {
if (strlen(hex) != 2 * len) {
fprintf(stderr, "Key (%s) must be %"PRIu32" hex digits!\n", hex, 2 * len);
exit(EXIT_FAILURE);
}
for (unsigned int i = 0; i < 2 * len; i++) {
if (!ishex(hex[i])) {
fprintf(stderr, "Key (%s) must be %"PRIu32" hex digits!\n", hex, 2 * len);
exit(EXIT_FAILURE);
}
}
memset(key, 0, len);
for (unsigned int i = 0; i < 2 * len; i++) {
char val = hextoi(hex[i]);
if ((i & 1) == 0) {
val <<= 4;
}
key[i >> 1] |= val;
}
}
void extkeys_initialize_keyset(nca_keyset_t *keyset, FILE *f) {
char *key, *value;
int ret;
while ((ret = get_kv(f, &key, &value)) != 1 && ret != -2) {
if (ret == 0) {
if (key == NULL || value == NULL) {
continue;
}
int matched_key = 0;
if (strcmp(key, "aes_kek_generation_source") == 0) {
parse_hex_key(keyset->aes_kek_generation_source, value, sizeof(keyset->aes_kek_generation_source));
matched_key = 1;
} else if (strcmp(key, "aes_key_generation_source") == 0) {
parse_hex_key(keyset->aes_key_generation_source, value, sizeof(keyset->aes_key_generation_source));
matched_key = 1;
} else if (strcmp(key, "key_area_key_application_source") == 0) {
parse_hex_key(keyset->key_area_key_application_source, value, sizeof(keyset->key_area_key_application_source));
matched_key = 1;
} else if (strcmp(key, "key_area_key_ocean_source") == 0) {
parse_hex_key(keyset->key_area_key_ocean_source, value, sizeof(keyset->key_area_key_ocean_source));
matched_key = 1;
} else if (strcmp(key, "key_area_key_system_source") == 0) {
parse_hex_key(keyset->key_area_key_system_source, value, sizeof(keyset->key_area_key_system_source));
matched_key = 1;
} else if (strcmp(key, "titlekek_source") == 0) {
parse_hex_key(keyset->titlekek_source, value, sizeof(keyset->titlekek_source));
matched_key = 1;
} else if (strcmp(key, "header_kek_source") == 0) {
parse_hex_key(keyset->header_kek_source, value, sizeof(keyset->header_kek_source));
matched_key = 1;
} else if (strcmp(key, "header_key_source") == 0) {
parse_hex_key(keyset->encrypted_header_key, value, sizeof(keyset->encrypted_header_key));
matched_key = 1;
} else if (strcmp(key, "header_key") == 0) {
parse_hex_key(keyset->header_key, value, sizeof(keyset->header_key));
matched_key = 1;
} else if (strcmp(key, "encrypted_header_key") == 0) {
parse_hex_key(keyset->encrypted_header_key, value, sizeof(keyset->encrypted_header_key));
matched_key = 1;
} else if (strcmp(key, "package2_key_source") == 0) {
parse_hex_key(keyset->package2_key_source, value, sizeof(keyset->package2_key_source));
matched_key = 1;
} else if (strcmp(key, "sd_card_kek_source") == 0) {
parse_hex_key(keyset->sd_card_kek_source, value, sizeof(keyset->sd_card_kek_source));
matched_key = 1;
} else if (strcmp(key, "sd_card_nca_key_source") == 0) {
parse_hex_key(keyset->sd_card_key_sources[1], value, sizeof(keyset->sd_card_key_sources[1]));
matched_key = 1;
} else if (strcmp(key, "sd_card_save_key_source") == 0) {
parse_hex_key(keyset->sd_card_key_sources[0], value, sizeof(keyset->sd_card_key_sources[0]));
matched_key = 1;
} else if (strcmp(key, "master_key_source") == 0) {
parse_hex_key(keyset->master_key_source, value, sizeof(keyset->master_key_source));
matched_key = 1;
} else if (strcmp(key, "keyblob_mac_key_source") == 0) {
parse_hex_key(keyset->keyblob_mac_key_source, value, sizeof(keyset->keyblob_mac_key_source));
matched_key = 1;
} else if (strcmp(key, "secure_boot_key") == 0) {
parse_hex_key(keyset->secure_boot_key, value, sizeof(keyset->secure_boot_key));
matched_key = 1;
} else if (strcmp(key, "tsec_key") == 0) {
parse_hex_key(keyset->tsec_key, value, sizeof(keyset->tsec_key));
matched_key = 1;
} else {
char test_name[0x100];
memset(test_name, 0, sizeof(100));
for (unsigned int i = 0; i < 0x20 && !matched_key; i++) {
snprintf(test_name, sizeof(test_name), "keyblob_key_source_%02"PRIx32, i);
if (strcmp(key, test_name) == 0) {
parse_hex_key(keyset->keyblob_key_sources[i], value, sizeof(keyset->keyblob_key_sources[i]));
matched_key = 1;
break;
}
snprintf(test_name, sizeof(test_name), "keyblob_key_%02"PRIx32, i);
if (strcmp(key, test_name) == 0) {
parse_hex_key(keyset->keyblob_keys[i], value, sizeof(keyset->keyblob_keys[i]));
matched_key = 1;
break;
}
snprintf(test_name, sizeof(test_name), "keyblob_mac_key_%02"PRIx32, i);
if (strcmp(key, test_name) == 0) {
parse_hex_key(keyset->keyblob_mac_keys[i], value, sizeof(keyset->keyblob_mac_keys[i]));
matched_key = 1;
break;
}
snprintf(test_name, sizeof(test_name), "encrypted_keyblob_%02"PRIx32, i);
if (strcmp(key, test_name) == 0) {
parse_hex_key(keyset->encrypted_keyblobs[i], value, sizeof(keyset->encrypted_keyblobs[i]));
matched_key = 1;
break;
}
snprintf(test_name, sizeof(test_name), "keyblob_%02"PRIx32, i);
if (strcmp(key, test_name) == 0) {
parse_hex_key(keyset->keyblobs[i], value, sizeof(keyset->keyblobs[i]));
matched_key = 1;
break;
}
snprintf(test_name, sizeof(test_name), "master_key_%02"PRIx32, i);
if (strcmp(key, test_name) == 0) {
parse_hex_key(keyset->master_keys[i], value, sizeof(keyset->master_keys[i]));
matched_key = 1;
break;
}
snprintf(test_name, sizeof(test_name), "package1_key_%02"PRIx32, i);
if (strcmp(key, test_name) == 0) {
parse_hex_key(keyset->package1_keys[i], value, sizeof(keyset->package1_keys[i]));
matched_key = 1;
break;
}
snprintf(test_name, sizeof(test_name), "package2_key_%02"PRIx32, i);
if (strcmp(key, test_name) == 0) {
parse_hex_key(keyset->package2_keys[i], value, sizeof(keyset->package2_keys[i]));
matched_key = 1;
break;
}
snprintf(test_name, sizeof(test_name), "titlekek_%02"PRIx32, i);
if (strcmp(key, test_name) == 0) {
parse_hex_key(keyset->titlekeks[i], value, sizeof(keyset->titlekeks[i]));
matched_key = 1;
break;
}
snprintf(test_name, sizeof(test_name), "key_area_key_application_%02"PRIx32, i);
if (strcmp(key, test_name) == 0) {
parse_hex_key(keyset->key_area_keys[i][0], value, sizeof(keyset->key_area_keys[i][0]));
matched_key = 1;
break;
}
snprintf(test_name, sizeof(test_name), "key_area_key_ocean_%02"PRIx32, i);
if (strcmp(key, test_name) == 0) {
parse_hex_key(keyset->key_area_keys[i][1], value, sizeof(keyset->key_area_keys[i][1]));
matched_key = 1;
break;
}
snprintf(test_name, sizeof(test_name), "key_area_key_system_%02"PRIx32, i);
if (strcmp(key, test_name) == 0) {
parse_hex_key(keyset->key_area_keys[i][2], value, sizeof(keyset->key_area_keys[i][2]));
matched_key = 1;
break;
}
}
}
if (!matched_key) {
fprintf(stderr, "[WARN]: Failed to match key \"%s\", (value \"%s\")\n", key, value);
}
}
}
}