void ivfc_fseek(ivfc_context* ctx, u64 offset)
{
u64 data_pos = offset - ctx->offset;
fseeko64(ctx->file, offset, SEEK_SET);
ctr_init_counter(&ctx->aes, ctx->key, ctx->counter);
ctr_add_counter(&ctx->aes, (u32) (data_pos / 0x10));
}
void exefs_read_header(exefs_context* ctx, u32 flags)
{
fseek(ctx->file, ctx->offset, SEEK_SET);
fread(&ctx->header, 1, sizeof(exefs_header), ctx->file);
ctr_init_counter(&ctx->aes, ctx->key, ctx->counter);
if (ctx->encrypted)
ctr_crypt_counter(&ctx->aes, (u8*)&ctx->header, (u8*)&ctx->header, sizeof(exefs_header));
}
int VerifyNCCHSection(USER_CONTEXT *ctx, u8 cxi_key[0x10], u32 offset, FILE *ncch)
{
NCCH_STRUCT *cxi_ctx = malloc(sizeof(NCCH_STRUCT));
if(cxi_ctx == NULL){
printf("[!] Memory Allocation Failure\n");
return Fail;
}
memset(cxi_ctx,0x0,sizeof(NCCH_STRUCT));
GetCXIStruct(cxi_ctx,offset,ncch);
u8 HeaderSignature[0x100];
u8 Header[0x100];
u8 HeaderSHAHash[0x20];
u8 ExHeader[0x800];
memset(&HeaderSignature,0x0,0x100);
memset(&Header,0x0,0x100);
memset(&HeaderSHAHash,0x0,0x20);
fseek(ncch,offset+0x0,SEEK_SET);
fread(HeaderSignature,0x100,1,ncch);
fread(Header,0x100,1,ncch);
ctr_sha(&Header,0x100,HeaderSHAHash,CTR_SHA_256);
RSA_2048_KEY HeaderRSA;
memset(&HeaderRSA,0x0,sizeof(RSA_2048_KEY));
u8 Exponent[0x3] = {0x01,0x00,0x01};
memcpy(HeaderRSA.e,Exponent,0x3);
if(cxi_ctx->is_cfa == True)
memcpy(HeaderRSA.n,ctx->keys.NcsdCfa.n,0x100);
else{
memset(&ExHeader,0x0,0x800);
fseek(ncch,offset+cxi_ctx->exheader_offset,SEEK_SET);
fread(&ExHeader,0x800,1,ncch);
if(cxi_ctx->encrypted == True){
u8 counter[0x10];
ncch_get_counter(cxi_ctx,counter,NCCHTYPE_EXHEADER);
ctr_aes_context aes_ctx;
memset(&aes_ctx,0x0,sizeof(ctr_aes_context));
ctr_init_counter(&aes_ctx, cxi_key, counter);
ctr_crypt_counter(&aes_ctx, ExHeader, ExHeader, 0x800);
if(memcmp((ExHeader+0x200),cxi_ctx->programID,8) != 0){
printf("[!] CXI decryption failed\n");
return Fail;
}
}
memcpy(HeaderRSA.n,ExHeader+0x500,0x100);
}
return ctr_rsa(HeaderSHAHash,HeaderSignature,HeaderRSA.n,NULL,RSA_2048_SHA256,CTR_RSA_VERIFY);
}
int exefs_verify(exefs_context* ctx, u32 index, u32 flags)
{
exefs_sectionheader* section = (exefs_sectionheader*)(ctx->header.section + index);
u32 offset;
u32 size;
u8 buffer[16 * 1024];
u8 hash[0x20];
offset = getle32(section->offset) + sizeof(exefs_header);
size = getle32(section->size);
if (size == 0)
return 0;
fseek(ctx->file, ctx->offset + offset, SEEK_SET);
ctr_init_counter(&ctx->aes, ctx->key, ctx->counter);
ctr_add_counter(&ctx->aes, offset / 0x10);
ctr_sha_256_init(&ctx->sha);
while(size)
{
u32 max = sizeof(buffer);
if (max > size)
max = size;
if (max != fread(buffer, 1, max, ctx->file))
{
fprintf(stdout, "Error reading input file\n");
goto clean;
}
if (ctx->encrypted)
ctr_crypt_counter(&ctx->aes, buffer, buffer, max);
ctr_sha_256_update(&ctx->sha, buffer, max);
size -= max;
}
ctr_sha_256_finish(&ctx->sha, hash);
if (memcmp(hash, ctx->header.hashes[7-index], 0x20) == 0)
return 1;
clean:
return 0;
}
void CryptNcchRegion(u8 *buffer, u64 size, u64 src_pos, ncch_info *ctx, u8 key[16], u8 type)
{
if(type < 1 || type > 3)
return;
u8 counter[0x10];
ctr_aes_context aes_ctx;
memset(&aes_ctx,0x0,sizeof(ctr_aes_context));
GetNcchAesCounter(ctx,counter,type);
ctr_init_counter(&aes_ctx, key, counter);
if(src_pos > 0){
u32 carry = 0;
carry = align(src_pos,0x10);
carry /= 0x10;
ctr_add_counter(&aes_ctx,carry);
}
ctr_crypt_counter(&aes_ctx, buffer, buffer, size);
return;
}
void exefs_save(exefs_context* ctx, u32 index, u32 flags)
{
exefs_sectionheader* section = (exefs_sectionheader*)(ctx->header.section + index);
char outfname[MAX_PATH];
char name[64];
u32 offset;
u32 size;
FILE* fout;
u32 compressedsize = 0;
u32 decompressedsize = 0;
u8* compressedbuffer = 0;
u8* decompressedbuffer = 0;
filepath* dirpath = 0;
offset = getle32(section->offset) + sizeof(exefs_header);
size = getle32(section->size);
dirpath = settings_get_exefs_dir_path(ctx->usersettings);
if (size == 0 || dirpath == 0 || dirpath->valid == 0)
return;
if (size >= ctx->size)
{
fprintf(stderr, "Error, ExeFS section %d size invalid\n", index);
return;
}
memset(name, 0, sizeof(name));
memcpy(name, section->name, 8);
memcpy(outfname, dirpath->pathname, MAX_PATH);
strcat(outfname, "/");
if (name[0] == '.')
strcat(outfname, name+1);
else
strcat(outfname, name);
strcat(outfname, ".bin");
fout = fopen(outfname, "wb");
if (fout == 0)
{
fprintf(stderr, "Error, failed to create file %s\n", outfname);
goto clean;
}
fseek(ctx->file, ctx->offset + offset, SEEK_SET);
ctr_init_counter(&ctx->aes, ctx->key, ctx->counter);
ctr_add_counter(&ctx->aes, offset / 0x10);
if (index == 0 && (ctx->compressedflag || (flags & CompressCodeFlag)) && ((flags & RawFlag) == 0))
{
fprintf(stdout, "Decompressing section %s to %s...\n", name, outfname);
compressedsize = size;
compressedbuffer = malloc(compressedsize);
if (compressedbuffer == 0)
{
fprintf(stdout, "Error allocating memory\n");
goto clean;
}
if (compressedsize != fread(compressedbuffer, 1, compressedsize, ctx->file))
{
fprintf(stdout, "Error reading input file\n");
goto clean;
}
if (ctx->encrypted)
ctr_crypt_counter(&ctx->aes, compressedbuffer, compressedbuffer, compressedsize);
decompressedsize = lzss_get_decompressed_size(compressedbuffer, compressedsize);
decompressedbuffer = malloc(decompressedsize);
if (decompressedbuffer == 0)
{
fprintf(stdout, "Error allocating memory\n");
goto clean;
}
if (0 == lzss_decompress(compressedbuffer, compressedsize, decompressedbuffer, decompressedsize))
goto clean;
if (decompressedsize != fwrite(decompressedbuffer, 1, decompressedsize, fout))
{
fprintf(stdout, "Error writing output file\n");
goto clean;
}
}
else
{
u8 buffer[16 * 1024];
fprintf(stdout, "Saving section %s to %s...\n", name, outfname);
while(size)
{
u32 max = sizeof(buffer);
if (max > size)
max = size;
if (max != fread(buffer, 1, max, ctx->file))
{
fprintf(stdout, "Error reading input file\n");
goto clean;
}
if (ctx->encrypted)
ctr_crypt_counter(&ctx->aes, buffer, buffer, max);
if (max != fwrite(buffer, 1, max, fout))
{
fprintf(stdout, "Error writing output file\n");
goto clean;
}
size -= max;
}
}
clean:
free(compressedbuffer);
free(decompressedbuffer);
return;
}
