1 files changed, 82 insertions, 0 deletions
diff --git a/crypto_buffer.c b/crypto_buffer.c
new file mode 100644
index 0000000..d17e805
--- /dev/null
+++ b/crypto_buffer.c
@@ -0,0 +1,82 @@
+#include <stdlib.h>
+#include <string.h>
+
+#include "crypto_buffer.h"
+
+
+#include <stdio.h>
+int crypto_buffer_init(crypto_buffer *s, int fd, operation op, u32 blocks, int type, u8 *key, u32 key_len)
+{
+	int ret;
+	int size;
+	
+	if(blocks<3) return -1;	/* magic + info + data */
+	
+	s->fd = fd;
+	s->op = op;
+	
+	if(type & BLOWFISH){
+		size = BF_BLOCK_SIZE;
+		ret = blowfish_setkey((struct blowfish_ctx*)&s->ctx, key, key_len, 0);
+		if(type & DECRYPT){ s->cipher = blowfish_decrypt; }
+		else { s->cipher = blowfish_encrypt; }
+	}
+	else if(type & TWOFISH){
+		size = TF_BLOCK_SIZE;
+		ret = twofish_setkey((struct twofish_ctx*)&s->ctx, key, key_len, 0);
+		if(type & DECRYPT) { s->cipher = twofish_decrypt; }
+		else {s->cipher = twofish_encrypt; }
+	}
+	else if(type & AES){
+		size = AES_BLOCK_SIZE;
+		ret = aes_setkey((struct aes_ctx*)&s->ctx, key, key_len, 0);
+		if(type & DECRYPT) { s->cipher = aes_decrypt; }
+		else {s->cipher = aes_encrypt; }
+	}
+	else if(type & DES){
+		size = DES_BLOCK_SIZE;
+		ret = des_setkey((struct des_ctx*)&s->ctx, key, key_len, 0);
+		if(type & DECRYPT) { s->cipher = des_decrypt; }
+		else {s->cipher = des_encrypt; }
+	}
+	else if(type & DES3_EDE){
+		size = DES3_EDE_BLOCK_SIZE;
+		ret = des3_ede_setkey((struct des3_ede_ctx*)&s->ctx, key, key_len, 0);
+		if(type & DECRYPT) { s->cipher = des3_ede_decrypt; }
+		else {s->cipher = des3_ede_encrypt; }
+	}
+	else return -1;
+	if(ret!=0) return -1;
+
+	if((U32_MAX / size) < blocks) return -1;
+	
+	s->block_size = size;
+	s->e_len = size * blocks;		/* TODO check overflow */
+	s->data_st.bytes = s->data_st.strlen = 0;
+	/* clear buffer */
+	s->c_buffer = malloc(size);
+	if(s->c_buffer==NULL) return -1;
+	s->c_ptr = s->c_buffer;
+	s->c_end = s->c_buffer + size;
+	/* encrypte buffer */
+	s->e_buffer = malloc(s->e_len);
+	if(s->e_buffer==NULL) return -1;
+	memset(s->e_buffer,0x5a,size);		/* for write operation */
+	s->e_data = (struct info*)(s->e_buffer + size);
+	s->e_end = s->e_buffer + s->e_len;
+	if(type & DECRYPT){
+		s->e_ptr = s->e_buffer;
+	}
+	else{
+		s->e_ptr = s->e_buffer + (size << 1);
+		s->e_len -= (size << 1);
+	}
+/*	
+	fprintf(stderr,"e_buffer  : %x\n",s->e_buffer);
+	fprintf(stderr,"e_data    : %x\n",s->e_data);
+	fprintf(stderr,"e_ptr     : %x\n",s->e_ptr);
+	fprintf(stderr,"e_end     : %x\n",s->e_end);
+	fprintf(stderr,"length    : %d\n",s->e_len);
+*/
+	return ret;
+}