From 92ecbd5fb8a7c8e939b1b4dde82cc6c9ba9d41af Mon Sep 17 00:00:00 2001 From: Amaury Pouly Date: Wed, 4 Jan 2017 16:36:27 +0100 Subject: nwztools/upg: move upg handling to its own file, completely rework kas handling This was a huge mess, the new is much cleaner hopefully. Change-Id: I43663d021dc8bc31662d3923e1c3da22d987ebf9 --- utils/nwztools/upgtools/upgtool.c | 436 +++++++------------------------------- 1 file changed, 76 insertions(+), 360 deletions(-) (limited to 'utils/nwztools/upgtools/upgtool.c') diff --git a/utils/nwztools/upgtools/upgtool.c b/utils/nwztools/upgtools/upgtool.c index 833321ec12..0de46a4260 100644 --- a/utils/nwztools/upgtools/upgtool.c +++ b/utils/nwztools/upgtools/upgtool.c @@ -33,6 +33,7 @@ #include "crypt.h" #include "fwp.h" #include "keysig_search.h" +#include "upg.h" #ifndef MIN #define MIN(a,b) ((a) < (b) ? (a) : (b)) @@ -59,183 +60,11 @@ enum keysig_search_method_t g_keysig_search = KEYSIG_SEARCH_NONE; { cprintf(RED, str_bad); let_the_force_flow(__LINE__); } \ else { cprintf(RED, str_ok); } -static void usage(void); - -#define HAS_KAS (1 << 0) -#define HAS_KEY (1 << 1) -#define HAS_SIG (1 << 2) -#define CONFIRMED (1 << 3) - -struct nwz_model_t -{ - const char *model; - unsigned flags; - char *kas; - char *key; - char *sig; -}; - -/** Firmware format - * - * The firmware starts with the MD5 hash of the entire file (except the MD5 hash - * itself of course). This is used to check that the file was not corrupted. - * The remaining of the file is encrypted (using DES) with the model key. The - * encrypted part starts with a header containing the model signature and the - * number of files. Since the header is encrypted, decrypting the header with - * the key and finding the right signature serves to authenticate the firmware. - * The header is followed by N entries (where N is the number of files) giving - * the offset, within the file, and size of each file. Note that the files in - * the firmware have no name. */ - -struct upg_md5_t -{ - uint8_t md5[16]; -}__attribute__((packed)); - -struct upg_header_t -{ - uint8_t sig[NWZ_SIG_SIZE]; - uint32_t nr_files; - uint32_t pad; // make sure structure size is a multiple of 8 -} __attribute__((packed)); - -struct upg_entry_t -{ - uint32_t offset; - uint32_t size; -} __attribute__((packed)); - -/** KAS / Key / Signature - * - * Since this is all very confusing, we need some terminology and notations: - * - [X, Y, Z] is a sequence of bytes, for example: - * [8, 0x89, 42] - * is a sequence of three bytes. - * - "abcdef" is a string: it is a sequences of bytes where each byte happens to - * be the ASCII encoding of a letter. So for example: - * "abc" = [97, 98, 99] - * because 'a' has ASCII encoding 97 and so one - * - HexString(Seq) refers to the string where each byte of the original sequence - * is represented in hexadecimal by two ASCII characters. For example: - * HexString([8, 0x89, 42]) = "08892a" - * because 8 = 0x08 so it represented by "08" and 42 = 0x2a. Note that the length - * of HexString(Seq) is always exactly twice the length of Seq. - * - DES(Seq,Pass) is the result of encrypting Seq with Pass using the DES cipher. - * Seq must be a sequence of 8 bytes (known as a block) and Pass must be a - * sequence of 8 bytes. The result is also a 8-byte sequence. - * - ECB_DES([Block0, Block1, ..., BlockN], Pass) - * = [DES(Block0,Pass), DES(Block1,Pass), ..., DES(BlockN,Pass)] - * where Blocki is a block (8 byte). - * - * - * A firmware upgrade file is always encrypted using a Key. To authenticate it, - * the upgrade file (before encryption) contains a Sig(nature). The pair (Key,Sig) - * is refered to as KeySig and is specific to each series. For example all - * NWZ-E46x use the same KeySig but the NWZ-E46x and NWZ-A86x use different KeySig. - * In the details, a Key is a sequence of 8 bytes and a Sig is also a sequence - * of 8 bytes. A KeySig is a simply the concatenation of the Key followed by - * the Sig, so it is a sequence of 16 bytes. Probably in an attempt to obfuscate - * things a little further, Sony never provides the KeySig directly but instead - * encrypts it using DES in ECB mode using a hardcoded password and provides - * the hexadecimal string of the result, known as the KAS, which is thus a string - * of 32 ASCII characters. - * Note that since DES works on blocks of 8 bytes and ECB encrypts blocks - * independently, it is the same to encrypt the KeySig as once or encrypt the Key - * and Sig separately. - * - * To summarize: - * Key = [K0, K1, K2, ..., K7] (8 bytes) (model specific) - * Sig = [S0, S1, S2, ..., S7] (8 bytes) (model specific) - * KeySig = [Key, Sig] = [K0, ... K7, S0, ..., S7] (16 bytes) - * FwpPass = "ed295076" (8 bytes) (never changes) - * EncKeySig = ECB_DES(KeySig, FwpPass) = [DES(Key, FwpPass), DES(Sig, FwpPass)] - * KAS = HexString(EncKeySig) (32 characters) - * - * In theory, the Key and Sig can be any 8-byte sequence. In practice, they always - * are strings, probably to make it easier to write them down. In many cases, the - * Key and Sig are even the hexadecimal string of 4-byte sequences but it is - * unclear if this is the result of pure luck, confused engineers, lazyness on - * Sony's part or by design. The following code assumes that Key and Sig are - * strings (though it could easily be fixed to work with anything if this is - * really needed). - * - * - * Here is a real example, from the NWZ-E46x Series: - * Key = "6173819e" (note that this is a string and even a hex string in this case) - * Sig = "30b82e5c" - * KeySig = [Key, Sig] = "6173819e30b82e5c" - * FwpPass = "ed295076" (never changes) - * EncKeySig = ECB_DES(KeySig, FwpPass) - * = [0x8a, 0x01, 0xb6, ..., 0xc5] (16 bytes) - * KAS = HexString(EncKeySig) = "8a01b624bfbfde4a1662a1772220e3c5" - * - */ +#define cprintf(col, ...) do {color(col); printf(__VA_ARGS__); }while(0) -struct nwz_model_t g_model_list[] = -{ - { "nwz-e450", HAS_KAS | CONFIRMED, "8a01b624bfbfde4a1662a1772220e3c5", "", "" }, - { "nwz-e460", HAS_KAS | CONFIRMED, "89d813f8f966efdebd9c9e0ea98156d2", "", "" }, - { "nwz-a860", HAS_KAS | CONFIRMED, "a7c4af6c28b8900a783f307c1ba538c5", "", "" }, - { "nwz-a850", HAS_KAS | CONFIRMED, "a2efb9168616c2e84d78291295c1aa5d", "", "" }, - { "nwz-e470", HAS_KAS | CONFIRMED, "e4144baaa2707913f17b5634034262c4", "", "" }, - /* The following keys were obtained by brute forcing firmware upgrades, - * someone with a device needs to confirm that they work */ - { "nw-a820", HAS_KEY | HAS_SIG, "", "4df06482", "07fa0b6e" }, - { "nwz-a10", HAS_KEY | HAS_SIG, "", "ec2888e2", "f62ced8a" }, - { "nwz-a20", HAS_KEY | HAS_SIG, "", "e8e204ee", "577614df" }, - { "nwz-zx100", HAS_KEY | HAS_SIG, "", "22e44606", "a9f95e90" }, - { "nwz-e580", HAS_KEY | HAS_SIG, "", "a60806ea", "97e8ce46" }, -}; - -static int digit_value(char c) -{ - if(c >= '0' && c <= '9') return c - '0'; - if(c >= 'a' && c <= 'f') return c - 'a' + 10; - if(c >= 'A' && c <= 'F') return c - 'A' + 10; - return -1; -} +#define cprintf_field(str1, ...) do{ cprintf(GREEN, str1); cprintf(YELLOW, __VA_ARGS__); }while(0) -static char hex_digit(unsigned v) -{ - return (v < 10) ? v + '0' : (v < 16) ? v - 10 + 'a' : 'x'; -} - -static int decrypt_keysig(const char kas[NWZ_KAS_SIZE], char key[NWZ_KEY_SIZE], - char sig[NWZ_SIG_SIZE]) -{ - uint8_t src[NWZ_KAS_SIZE / 2]; - for(int index = 0; index < NWZ_KAS_SIZE / 2; index++) - { - int a = digit_value(kas[index * 2]); - int b = digit_value(kas[index * 2 + 1]); - if(a < 0 || b < 0) - { - cprintf(GREY, "Invalid KAS !\n"); - return -1; - } - src[index] = a << 4 | b; - } - fwp_setkey("ed295076"); - fwp_crypt(src, sizeof(src), 1); - memcpy(key, src, NWZ_KEY_SIZE); - memcpy(sig, src + NWZ_KEY_SIZE, NWZ_SIG_SIZE); - return 0; -} - -static void encrypt_keysig(char kas[NWZ_KEY_SIZE], - const char key[NWZ_SIG_SIZE], const char sig[NWZ_KAS_SIZE]) -{ - uint8_t src[NWZ_KAS_SIZE / 2]; - fwp_setkey("ed295076"); - memcpy(src, key, NWZ_KEY_SIZE); - memcpy(src + NWZ_KEY_SIZE, sig, NWZ_SIG_SIZE); - fwp_crypt(src, sizeof(src), 0); - for(int i = 0; i < NWZ_KAS_SIZE / 2; i++) - { - kas[2 * i] = hex_digit((src[i] >> 4) & 0xf); - kas[2 * i + 1] = hex_digit(src[i] & 0xf); - } -} +static void usage(void); /* user needs to be pointer to a NWZ_KEYSIG_SIZE-byte buffer, on success g_key * and g_sig are updated to point to the key and sig in the buffer */ @@ -249,20 +78,13 @@ static bool upg_notify_keysig(void *user, uint8_t key[NWZ_KEY_SIZE], return true; } -static int get_key_and_sig(bool is_extract, void *encrypted_hdr) +static int get_key_and_sig(bool is_extract, void *buf) { static char keysig[NWZ_KEYSIG_SIZE]; static char kas[NWZ_KAS_SIZE]; /* database lookup */ if(g_model_index != -1) - { - if(g_model_list[g_model_index].flags & HAS_KAS) - g_kas = g_model_list[g_model_index].kas; - if(g_model_list[g_model_index].flags & HAS_KEY) - g_key = g_model_list[g_model_index].key; - if(g_model_list[g_model_index].flags & HAS_SIG) - g_sig = g_model_list[g_model_index].sig; - } + g_kas = g_model_list[g_model_index].kas; /* always prefer KAS because it contains everything */ if(g_kas) @@ -276,33 +98,26 @@ static int get_key_and_sig(bool is_extract, void *encrypted_hdr) g_sig = keysig + NWZ_KEY_SIZE; decrypt_keysig(g_kas, g_key, g_sig); } - /* fall back to key and signature otherwise. The signature is not required - * when extracting but prevents from checking decryption */ - else if(g_key && (is_extract || g_sig)) + /* Otherwise require key and signature */ + else if(g_key && g_sig) { + /* check key and signature size */ if(strlen(g_key) != 8) { cprintf(GREY, "The specified key has wrong length (must be 8 hex digits)\n"); return 4; } - - /* if there is a signature, it must have the correct size */ - if(g_sig) + if(strlen(g_sig) != 8) { - if(strlen(g_sig) != 8) - { - cprintf(GREY, "The specified sig has wrong length (must be 8 hex digits)\n"); - return 5; - } - } - else - { - cprintf(GREY, "Warning: you have specified a key but no sig, I won't be able to do any checks\n"); + cprintf(GREY, "The specified sig has wrong length (must be 8 hex digits)\n"); + return 5; } } /* for extraction, we offer a brute force search method from the MD5 */ else if(is_extract && g_keysig_search != KEYSIG_SEARCH_NONE) { + struct upg_md5_t *md5 = (void *)buf; + void *encrypted_hdr = (md5 + 1); cprintf(BLUE, "keysig Search\n"); cprintf_field(" Method: ", "%s\n", keysig_search_desc[g_keysig_search].name); bool ok = keysig_search(g_keysig_search, encrypted_hdr, 8, @@ -329,13 +144,8 @@ static int get_key_and_sig(bool is_extract, void *encrypted_hdr) * valid files anyway */ if(!g_kas) { - if(!g_sig) - { - /* if we extract and don't have a signature, just use a random - * one, we cannot check it anyway */ - g_sig = keysig; - memset(g_sig, '?', NWZ_SIG_SIZE); - } + /* This is useful to print the KAS for the user when brute-forcing since + * the process will produce a key+sig and the database requires a KAS */ g_kas = kas; encrypt_keysig(g_kas, g_key, g_sig); } @@ -343,86 +153,38 @@ static int get_key_and_sig(bool is_extract, void *encrypted_hdr) cprintf(BLUE, "Keys\n"); cprintf_field(" KAS: ", "%."STR(NWZ_KAS_SIZE)"s\n", g_kas); cprintf_field(" Key: ", "%."STR(NWZ_KEY_SIZE)"s\n", g_key); - if(g_sig) - cprintf_field(" Sig: ", "%."STR(NWZ_SIG_SIZE)"s\n", g_sig); + cprintf_field(" Sig: ", "%."STR(NWZ_SIG_SIZE)"s\n", g_sig); return 0; } static int do_upg(void *buf, long size) { - struct upg_md5_t *md5 = buf; - cprintf(BLUE, "Preliminary\n"); - cprintf(GREEN, " MD5: "); - for(int i = 0; i < 16; i++) - cprintf(YELLOW, "%02x", md5->md5[i]); - printf(" "); - - uint8_t actual_md5[MD5_DIGEST_LENGTH]; - { - MD5_CTX c; - MD5_Init(&c); - MD5_Update(&c, md5 + 1, size - sizeof(struct upg_header_t)); - MD5_Final(actual_md5, &c); - } - check_field(memcmp(actual_md5, md5->md5, 16), 0, "Ok\n", "Mismatch\n"); - - int ret = get_key_and_sig(true, md5 + 1); + int ret = get_key_and_sig(true, buf); if(ret != 0) return ret; - - struct upg_header_t *hdr = (void *)(md5 + 1); - ret = fwp_read(hdr, sizeof(struct upg_header_t), hdr, (void *)g_key); - if(ret) + struct upg_file_t *file = upg_read_memory(buf, size, g_key, g_sig, NULL, + generic_std_printf); + if(file == NULL) return ret; - - cprintf(BLUE, "Header\n"); - cprintf_field(" Signature:", " "); - for(int i = 0; i < 8; i++) - cprintf(YELLOW, "%c", isprint(hdr->sig[i]) ? hdr->sig[i] : '.'); - if(g_sig) + for(int i = 0; i < file->nr_files; i++) { - check_field(memcmp(hdr->sig, g_sig, 8), 0, " OK\n", " Mismatch\n"); - } - else - cprintf(RED, " Can't check\n"); - cprintf_field(" Files: ", "%d\n", hdr->nr_files); - cprintf_field(" Pad: ", "0x%x\n", hdr->pad); - - cprintf(BLUE, "Files\n"); - struct upg_entry_t *entry = (void *)(hdr + 1); - for(unsigned i = 0; i < hdr->nr_files; i++, entry++) - { - int ret = fwp_read(entry, sizeof(struct upg_entry_t), entry, (void *)g_key); - if(ret) - return ret; - cprintf(GREY, " File"); - cprintf(RED, " %d\n", i); - cprintf_field(" Offset: ", "0x%x\n", entry->offset); - cprintf_field(" Size: ", "0x%x\n", entry->size); - - if(g_out_prefix) + if(!g_out_prefix) + continue; + char *str = malloc(strlen(g_out_prefix) + 32); + sprintf(str, "%s%d.bin", g_out_prefix, i); + FILE *f = fopen(str, "wb"); + if(!f) { - char *str = malloc(strlen(g_out_prefix) + 32); - sprintf(str, "%s%d.bin", g_out_prefix, i); - FILE *f = fopen(str, "wb"); - if(f) - { - // round up size, there is some padding done with random data - int crypt_size = ROUND_UP(entry->size, 8); - int ret = fwp_read(buf + entry->offset, crypt_size, - buf + entry->offset, (void *)g_key); - if(ret) - return ret; - // but write the *good* amount of data - fwrite(buf + entry->offset, 1, entry->size, f); - fclose(f); - } - else - cprintf(GREY, "Cannot open '%s' for writing\n", str); + cprintf(GREY, "Cannot open '%s' for writing\n", str); + free(str); + continue; } + free(str); + fwrite(file->files[i].data, 1, file->files[i].size, f); + fclose(f); } - + upg_free(file); return 0; } @@ -490,7 +252,7 @@ static int create_upg(int argc, char **argv) { if(argc == 0) { - printf("You must specify a firmware filename\n"); + cprintf(GREY, "You must specify a firmware filename\n"); usage(); } @@ -498,89 +260,55 @@ static int create_upg(int argc, char **argv) if(ret != 0) return ret; - FILE *fout = fopen(argv[0], "wb"); - if(fout == NULL) - { - printf("Cannot open output firmware file: %m\n"); - return 1; - } - + struct upg_file_t *upg = upg_new(); int nr_files = argc - 1; - FILE **files = malloc(nr_files * sizeof(FILE *)); for(int i = 0; i < nr_files; i++) { - files[i] = fopen(argv[1 + i], "rb"); - if(files[i] == NULL) + FILE *f = fopen(argv[1 + i], "rb"); + if(f == NULL) + { + upg_free(upg); + printf(GREY, "Cannot open input file '%s': %m\n", argv[i + 1]); + return 1; + } + size_t size = filesize(f); + void *buf = malloc(size); + if(fread(buf, 1, size, f) != size) { - printf("Cannot open input file '%s': %m\n", argv[i + 1]); + cprintf(GREY, "Cannot read input file '%s': %m\n", argv[i + 1]); + fclose(f); + upg_free(upg); return 1; } + fclose(f); + upg_append(upg, buf, size); } - struct upg_md5_t md5; - memset(&md5, 0, sizeof(md5)); - MD5_CTX c; - MD5_Init(&c); - // output a dummy md5 sum - fwrite(&md5, 1, sizeof(md5), fout); - // output the encrypted signature - struct upg_header_t hdr; - memcpy(hdr.sig, g_sig, 8); - hdr.nr_files = nr_files; - hdr.pad = 0; - - ret = fwp_write(&hdr, sizeof(hdr), &hdr, (void *)g_key); - if(ret) - return ret; - MD5_Update(&c, &hdr, sizeof(hdr)); - fwrite(&hdr, 1, sizeof(hdr), fout); - - // output file headers - long offset = sizeof(md5) + sizeof(hdr) + nr_files * sizeof(struct upg_entry_t); - for(int i = 0; i < nr_files; i++) + size_t size = 0; + void *buf = upg_write_memory(upg, g_key, g_sig, &size, NULL, generic_std_printf); + upg_free(upg); + if(buf == NULL) { - struct upg_entry_t entry; - entry.offset = offset; - entry.size = filesize(files[i]); - offset += ROUND_UP(entry.size, 8); // do it before encryption !! - - ret = fwp_write(&entry, sizeof(entry), &entry, (void *)g_key); - if(ret) - return ret; - MD5_Update(&c, &entry, sizeof(entry)); - fwrite(&entry, 1, sizeof(entry), fout); + cprintf(GREY, "Error creating UPG file\n"); + return 1; } - - cprintf(BLUE, "Files\n"); - for(int i = 0; i < nr_files; i++) + FILE *fout = fopen(argv[0], "wb"); + if(fout == NULL) { - long size = filesize(files[i]); - long r_size = ROUND_UP(size, 8); - cprintf(GREY, " File"); - cprintf(RED, " %d\n", i); - cprintf_field(" Offset: ", "0x%lx\n", ftell(fout)); - cprintf_field(" Size: ", "0x%lx\n", size); - - void *buf = malloc(r_size); - memset(buf, 0, r_size); - fread(buf, 1, size, files[i]); - fclose(files[i]); - - ret = fwp_write(buf, r_size, buf, (void *)g_key); - if(ret) - return ret; - MD5_Update(&c, buf, r_size); - fwrite(buf, 1, r_size, fout); - + cprintf(GREY, "Cannot open output firmware file: %m\n"); free(buf); + return 1; + } + if(fwrite(buf, 1, size, fout) != size) + { + cprintf(GREY, "Cannot write output file: %m\n"); + fclose(fout); + free(buf); + return 1; } - - fseek(fout, 0, SEEK_SET); - MD5_Final(md5.md5, &c); - fwrite(&md5, 1, sizeof(md5), fout); fclose(fout); - + free(buf); return 0; } @@ -703,25 +431,13 @@ int main(int argc, char **argv) if(g_model && strcmp(g_model, "?") == 0) { cprintf(BLUE, "Model list:\n"); - for(unsigned i = 0; i < sizeof(g_model_list) / sizeof(g_model_list[0]); i++) + for(unsigned i = 0; g_model_list[i].model; i++) { cprintf(GREEN, " %s:", g_model_list[i].model); - if(g_model_list[i].flags & HAS_KAS) - { - cprintf(RED, " kas="); - cprintf(YELLOW, "%."STR(NWZ_KAS_SIZE)"s", g_model_list[i].kas); - } - if(g_model_list[i].flags & HAS_KEY) - { - cprintf(RED, " key="); - cprintf(YELLOW, "%.8s", g_model_list[i].key); - } - if(g_model_list[i].flags & HAS_SIG) - { - cprintf(RED, " sig="); - cprintf(YELLOW, "%.8s", g_model_list[i].sig); - } - if(g_model_list[i].flags & CONFIRMED) + + cprintf(RED, " kas="); + cprintf(YELLOW, "%."STR(NWZ_KAS_SIZE)"s", g_model_list[i].kas); + if(g_model_list[i].confirmed) cprintf(RED, " confirmed"); else cprintf(RED, " guessed"); @@ -732,7 +448,7 @@ int main(int argc, char **argv) if(g_model) { - for(unsigned i = 0; i < sizeof(g_model_list) / sizeof(g_model_list[0]); i++) + for(unsigned i = 0; g_model_list[i].model; i++) if(strcmp(g_model, g_model_list[i].model) == 0) g_model_index = i; if(g_model_index == -1) -- cgit v1.2.3