bug fixing(tm)

[arm-crypto-lib.git] / rsa / rsa_basic.c

diff --git a/rsa/rsa_basic.c b/rsa/rsa_basic.c
index e71bc8cede1c23c3ff40aa3c2b8981d39fb84fdc..a166dfa2384909d6e3b2ce8f90cd277ab0421b52 100644 (file)
--- a/rsa/rsa_basic.c
+++ b/rsa/rsa_basic.c
@@ -29,6 +29,7 @@
 #if DEBUG
 #include "cli.h"
 #include "uart_lowlevel.h"
+#include "string-extras.h"
 #endif
 
 void rsa_enc(bigint_t* data, rsa_publickey_t* key){
@@ -108,8 +109,18 @@ uint8_t rsa_dec(bigint_t* data, rsa_privatekey_t* key){
 }
 
 void rsa_os2ip(bigint_t* dest, const void* data, uint32_t length_B){
+#if BIGINT_WORD_SIZE == 8
+       if(data){
+               memcpy(dest->wordv, data, length_B)
+       }
+       dest->length_B = length_B;
+#else
        uint8_t off;
-       off = length_B % sizeof(bigint_word_t);
+       off = (sizeof(bigint_word_t) - length_B % sizeof(bigint_word_t)) % sizeof(bigint_word_t);
+#if DEBUG
+       cli_putstr("\r\nDBG: off = 0x");
+       cli_hexdump_byte(off);
+#endif
        if(!data){
                if(off){
                        dest->wordv = realloc(dest->wordv, length_B + sizeof(bigint_word_t) - off);
@@ -117,19 +128,36 @@ void rsa_os2ip(bigint_t* dest, const void* data, uint32_t length_B){
                        memset(dest->wordv, 0, off);
                }
        }else{
+               memcpy((uint8_t*)dest->wordv + off, data, length_B);
                if(off){
-                       memcpy((uint8_t*)dest->wordv + off, data, length_B);
-                       memset(dest, 0, off);
-               }else{
-                       memcpy(dest->wordv, data, length_B);
+                       memset(dest->wordv, 0, off);
                }
        }
-       dest->length_B = (length_B + sizeof(bigint_word_t) - 1) / sizeof(bigint_word_t);
+       dest->length_B = (length_B + off) / sizeof(bigint_word_t);
+#if DEBUG
+       cli_putstr("\r\nDBG: dest->length_B = 0x");
+       cli_hexdump_rev(&(dest->length_B), 2);
+#endif
+#endif
        bigint_changeendianess(dest);
        bigint_adjust(dest);
 }
 
 void rsa_i2osp(void* dest, bigint_t* src, uint16_t* out_length_B){
+#if BIGINT_WORD_SIZE == 8
+       if(dest){
+               uint8_t *e = src->wordv + src->length_B;
+               uint16_t i;
+               for(i=src->length_B; i>0; --i){
+                       *((uint8_t*)dest) = *--e;
+                       dest = (uint8_t*)dest + 1;
+               }
+       }else{
+               bigint_changeendianess(src);
+       }
+
+       *out_length_B = src->length_B;
+#else
        *out_length_B = bigint_get_first_set_bit(src) / 8 + 1;
        if(dest){
                uint16_t i;
@@ -147,5 +175,6 @@ void rsa_i2osp(void* dest, bigint_t* src, uint16_t* out_length_B){
                        memmove(src->wordv, (uint8_t*)src->wordv+off, *out_length_B);
                }
        }
+#endif
 }