Class: AesAlg

Inherits:
Object
  • Object
show all
Defined in:
ext/ruby-aes/aes_alg.c

Instance Method Summary collapse

Constructor Details

#initialize(kl, mode, key, iv) ⇒ Object 



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# File 'ext/ruby-aes/aes_alg.c', line 791

static VALUE
rb_aes_initialize(VALUE self, VALUE kl, VALUE mode, VALUE key, VALUE iv)
{
    rb_aes_init(self, kl, mode, key, iv);

    return Qnil;
}

Instance Method Details

#c_extension ⇒ Object 



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# File 'ext/ruby-aes/aes_alg.c', line 695

static VALUE
rb_aes_c_extension()
{
    return Qtrue;
}

#decrypt_block(block) ⇒ Object 



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# File 'ext/ruby-aes/aes_alg.c', line 464

static VALUE
rb_aes_decrypt_block(VALUE self, VALUE block)
{
    return rb_str_new(aes_decrypt_block(DATA_PTR(self), RSTRING(block)->ptr), BLOCK_SIZE);
}

#decrypt_blocks(buffer) ⇒ Object 



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# File 'ext/ruby-aes/aes_alg.c', line 497

static VALUE
rb_aes_decrypt_blocks(VALUE self, VALUE buffer)
{
    AES     *data = DATA_PTR(self);
    VALUE   pt = rb_str_new("", 0);

    aes_decrypt_blocks(data, RSTRING(buffer)->len, RSTRING(buffer)->ptr, pt);

    return pt;
}

#decrypt_buffer(buffer) ⇒ Object 



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# File 'ext/ruby-aes/aes_alg.c', line 533

static VALUE
rb_aes_decrypt_buffer(VALUE self, VALUE buffer)
{
    AES *data = DATA_PTR(self);
    const char  *ptr = RSTRING(buffer)->ptr;
    int         i, len = RSTRING(buffer)->len;
    uchar       pad;
    VALUE       pt = rb_str_new("", 0);

    for (; len >= BLOCK_SIZE; len -= BLOCK_SIZE, ptr += BLOCK_SIZE)
        rb_str_cat(pt, aes_decrypt_block(data, ptr), BLOCK_SIZE);
    if (len == 0) {
        i = RSTRING(pt)->len;
        ptr = RSTRING(pt)->ptr + i - 1;
        pad = *ptr;
        if (pad < BLOCK_SIZE) {
            for (; i > 0 && pad == *ptr; ptr--, i--, len++);
            /*if (pad != len)
                rb_raise(rb_eRuntimeError, "Bad Block Padding");*/
            if (pad == len)
                rb_str_resize(pt, i);
        }
    } else/* if (len != 1)*/
        rb_raise(rb_eRuntimeError, "Bad Block Padding");
    return pt;
}

#encrypt_block(block) ⇒ Object 



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# File 'ext/ruby-aes/aes_alg.c', line 458

static VALUE
rb_aes_encrypt_block(VALUE self, VALUE block)
{
    return rb_str_new(aes_encrypt_block(DATA_PTR(self), RSTRING(block)->ptr), BLOCK_SIZE);
}

#encrypt_blocks(buffer) ⇒ Object 



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# File 'ext/ruby-aes/aes_alg.c', line 486

static VALUE
rb_aes_encrypt_blocks(VALUE self, VALUE buffer)
{
    AES     *data = DATA_PTR(self);
    VALUE   ct = rb_str_new("", 0);

    aes_encrypt_blocks(data, RSTRING(buffer)->len, RSTRING(buffer)->ptr, ct);

    return ct;
}

#encrypt_buffer(buffer) ⇒ Object 



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# File 'ext/ruby-aes/aes_alg.c', line 508

static VALUE
rb_aes_encrypt_buffer(VALUE self, VALUE buffer)
{
    AES         *data = DATA_PTR(self);
    const char  *ptr = RSTRING(buffer)->ptr;
    int         i, len = RSTRING(buffer)->len;
    uchar       pad, *buf;
    VALUE       ct = rb_str_new("", 0);

    for (; len >= BLOCK_SIZE; len -= BLOCK_SIZE, ptr += BLOCK_SIZE)
        rb_str_cat(ct, aes_encrypt_block(data, ptr), BLOCK_SIZE);
    if (len > 0 && len < BLOCK_SIZE) {
        pad = BLOCK_SIZE - len % BLOCK_SIZE;
        buf = ALLOC_N(uchar, BLOCK_SIZE);
        MEMCPY(buf, ptr, uchar, len);
        for (i = len; i < BLOCK_SIZE; i++)
            buf[i] = pad;
        rb_str_cat(ct, aes_encrypt_block(data, buf), BLOCK_SIZE);
        free(buf);
    }/* else
        rb_str_cat(ct, "\x0", 1);*/

    return ct;
}

#init(kl, mode, key, iv) ⇒ Object 



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# File 'ext/ruby-aes/aes_alg.c', line 701

static VALUE
rb_aes_init(VALUE self, VALUE kl, VALUE mode, VALUE key, VALUE iv)
{
    AES *data = DATA_PTR(self);

    data->kl = FIX2INT(kl);

    if (data->kl == 128) {
        data->nk = 4;
        data->nr = 10;
    } else if (data->kl == 192) {
        data->nk = 6;
        data->nr = 12;
    } else if (data->kl == 256) {
        data->nk = 8;
        data->nr = 14;
    } else {
        rb_raise(rb_eArgError, "Bad Key Length");
    }
    data->nb = 4;

    char *mode_str = RSTRING(mode)->ptr;
    if (!strncmp(mode_str, "ECB", 3)) data->mode = MODE_ECB;
    else if (!strncmp(mode_str, "CBC", 3)) data->mode = MODE_CBC;
    else if (!strncmp(mode_str, "CFB", 3)) data->mode = MODE_CFB;
    else if (!strncmp(mode_str, "OFB", 3)) data->mode = MODE_OFB;
    else rb_raise(rb_eArgError, "Bad AES mode");

    if (data->key) FREE(data->key);
    data->key = ALLOC_N(uchar, 32);
    MEMCPY(data->key, RSTRING(key)->ptr, uchar, RSTRING(key)->len > 32 ? 32 : RSTRING(key)->len);

    if (data->iv) FREE(data->iv);
    if (NIL_P(iv)) {
        data->iv = NULL;
    } else {
        data->iv = ALLOC_N(uchar, BLOCK_SIZE);
        MEMCPY(data->iv, RSTRING(iv)->ptr, uchar, BLOCK_SIZE);
    }

    decryption_key_schedule(data, data->key);

    return self;
}