site: Break out separate function for decrypting msg0

[secnet] / transform.c

diff --git a/transform.c b/transform.c
index 5497711..f55aa44 100644 (file)
--- a/transform.c
+++ b/transform.c
@@ -19,7 +19,6 @@
 
 struct transform {
     closure_t cl;
-    uint32_t line;
     struct transform_if ops;
     uint32_t max_seq_skew;
 };
@@ -73,8 +72,8 @@ static void transform_delkey(void *sst)
 {
     struct transform_inst *ti=sst;
 
-    memset(&ti->cryptkey,0,sizeof(ti->cryptkey));
-    memset(&ti->mackey,0,sizeof(ti->mackey));
+    FILLZERO(ti->cryptkey);
+    FILLZERO(ti->mackey);
     ti->keyed=False;
 }
 
@@ -172,6 +171,10 @@ static uint32_t transform_reverse(void *sst, struct buffer_if *buf,
        return 1;
     }
 
+    if (buf->size < 4 + 16 + 16) {
+       *errmsg="msg too short";
+       return 1;
+    }
 
     /* CBC */
     memset(iv,0,16);
@@ -182,6 +185,7 @@ static uint32_t transform_reverse(void *sst, struct buffer_if *buf,
     /* Assert bufsize is multiple of blocksize */
     if (buf->size&0xf) {
        *errmsg="msg not multiple of cipher blocksize";
+       return 1;
     }
     serpent_encrypt(&ti->cryptkey,iv,iv);
     for (n=buf->start; n<buf->start+buf->size; n+=16)
@@ -253,7 +257,7 @@ static void transform_destroy(void *sst)
 {
     struct transform_inst *st=sst;
 
-    memset(st,0,sizeof(*st)); /* Destroy key material */
+    FILLZERO(*st); /* Destroy key material */
     free(st);
 }