Clean up the AES enc_provider code a bit. Chiefly, work with unsigned

char blocks, casting input->data and output->data once each upon entry
to the non-IOV encrypt and decrypt functions, rather than casting our
working buffers each time we need to work with an outside function.

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@23428 dc483132-0cff-0310-8789-dd5450dbe970

1 files changed, 64 insertions, 80 deletions

diff --git a/src/lib/crypto/builtin/enc_provider/aes.c b/src/lib/crypto/builtin/enc_provider/aes.c
index cde5bb5..cfa3643 100644
--- a/src/lib/crypto/builtin/enc_provider/aes.c
+++ b/src/lib/crypto/builtin/enc_provider/aes.c
@@ -31,55 +31,24 @@
 #include <aead.h>
 #include <rand2key.h>
 
-#if 0
-aes_rval aes_blk_len(unsigned int blen, aes_ctx cx[1]);
-aes_rval aes_enc_key(const unsigned char in_key[], unsigned int klen, aes_ctx cx[1]);
-aes_rval aes_enc_blk(const unsigned char in_blk[], unsigned char out_blk[], const aes_ctx cx[1]);
-aes_rval aes_dec_key(const unsigned char in_key[], unsigned int klen, aes_ctx cx[1]);
-aes_rval aes_dec_blk(const unsigned char in_blk[], unsigned char out_blk[], const aes_ctx cx[1]);
-#endif
-
 #define CHECK_SIZES 0
 
-#if 0
-static void printd (const char *descr, krb5_data *d) {
-    int i, j;
-    const int r = 16;
-
-    printf("%s:", descr);
-
-    for (i = 0; i < d->length; i += r) {
-        printf("\n  %04x: ", i);
-        for (j = i; j < i + r && j < d->length; j++)
-            printf(" %02x", 0xff & d->data[j]);
-#ifdef SHOW_TEXT
-        for (; j < i + r; j++)
-            printf("   ");
-        printf("   ");
-        for (j = i; j < i + r && j < d->length; j++) {
-            int c = 0xff & d->data[j];
-            printf("%c", isprint(c) ? c : '.');
-        }
-#endif
-    }
-    printf("\n");
-}
-#endif
-
-static inline void enc(char *out, const char *in, aes_ctx *ctx)
+static inline void
+enc(unsigned char *out, const unsigned char *in, aes_ctx *ctx)
 {
-    if (aes_enc_blk((const unsigned char *)in, (unsigned char *)out, ctx)
-        != aes_good)
+    if (aes_enc_blk(in, out, ctx) != aes_good)
         abort();
 }
-static inline void dec(char *out, const char *in, aes_ctx *ctx)
+
+static inline void
+dec(unsigned char *out, const unsigned char *in, aes_ctx *ctx)
 {
-    if (aes_dec_blk((const unsigned char *)in, (unsigned char *)out, ctx)
-        != aes_good)
+    if (aes_dec_blk(in, out, ctx) != aes_good)
         abort();
 }
 
-static void xorblock(char *out, const char *in)
+static void
+xorblock(unsigned char *out, const unsigned char *in)
 {
     int z;
     for (z = 0; z < BLOCK_SIZE; z++)
@@ -91,8 +60,10 @@ krb5int_aes_encrypt(krb5_key key, const krb5_data *ivec,
                     const krb5_data *input, krb5_data *output)
 {
     aes_ctx ctx;
-    char tmp[BLOCK_SIZE], tmp2[BLOCK_SIZE], tmp3[BLOCK_SIZE];
+    unsigned char tmp[BLOCK_SIZE], tmp2[BLOCK_SIZE], tmp3[BLOCK_SIZE];
     int nblocks = 0, blockno;
+    const unsigned char *idata = (const unsigned char *) input->data;
+    unsigned char *odata = (unsigned char *) output->data;
 
 /*    CHECK_SIZES; */
 
@@ -109,31 +80,31 @@ krb5int_aes_encrypt(krb5_key key, const krb5_data *ivec,
 
     if (nblocks == 1) {
         /* XXX Used for DK function.  */
-        enc(output->data, input->data, &ctx);
+        enc(odata, idata, &ctx);
     } else {
         unsigned int nleft;
 
         for (blockno = 0; blockno < nblocks - 2; blockno++) {
-            xorblock(tmp, input->data + blockno * BLOCK_SIZE);
+            xorblock(tmp, idata + blockno * BLOCK_SIZE);
             enc(tmp2, tmp, &ctx);
-            memcpy(output->data + blockno * BLOCK_SIZE, tmp2, BLOCK_SIZE);
+            memcpy(odata + blockno * BLOCK_SIZE, tmp2, BLOCK_SIZE);
 
             /* Set up for next block.  */
             memcpy(tmp, tmp2, BLOCK_SIZE);
         }
         /* Do final CTS step for last two blocks (the second of which
            may or may not be incomplete).  */
-        xorblock(tmp, input->data + (nblocks - 2) * BLOCK_SIZE);
+        xorblock(tmp, idata + (nblocks - 2) * BLOCK_SIZE);
         enc(tmp2, tmp, &ctx);
         nleft = input->length - (nblocks - 1) * BLOCK_SIZE;
-        memcpy(output->data + (nblocks - 1) * BLOCK_SIZE, tmp2, nleft);
+        memcpy(odata + (nblocks - 1) * BLOCK_SIZE, tmp2, nleft);
         memcpy(tmp, tmp2, BLOCK_SIZE);
 
         memset(tmp3, 0, sizeof(tmp3));
-        memcpy(tmp3, input->data + (nblocks - 1) * BLOCK_SIZE, nleft);
+        memcpy(tmp3, idata + (nblocks - 1) * BLOCK_SIZE, nleft);
         xorblock(tmp, tmp3);
         enc(tmp2, tmp, &ctx);
-        memcpy(output->data + (nblocks - 2) * BLOCK_SIZE, tmp2, BLOCK_SIZE);
+        memcpy(odata + (nblocks - 2) * BLOCK_SIZE, tmp2, BLOCK_SIZE);
         if (ivec)
             memcpy(ivec->data, tmp2, BLOCK_SIZE);
     }
@@ -146,8 +117,10 @@ krb5int_aes_decrypt(krb5_key key, const krb5_data *ivec,
                     const krb5_data *input, krb5_data *output)
 {
     aes_ctx ctx;
-    char tmp[BLOCK_SIZE], tmp2[BLOCK_SIZE], tmp3[BLOCK_SIZE];
+    unsigned char tmp[BLOCK_SIZE], tmp2[BLOCK_SIZE], tmp3[BLOCK_SIZE];
     int nblocks = 0, blockno;
+    const unsigned char *idata = (const unsigned char *) input->data;
+    unsigned char *odata = (unsigned char *) output->data;
 
     CHECK_SIZES;
 
@@ -165,26 +138,26 @@ krb5int_aes_decrypt(krb5_key key, const krb5_data *ivec,
     if (nblocks == 1) {
         if (input->length < BLOCK_SIZE)
             abort();
-        dec(output->data, input->data, &ctx);
+        dec(odata, idata, &ctx);
     } else {
 
         for (blockno = 0; blockno < nblocks - 2; blockno++) {
-            dec(tmp2, input->data + blockno * BLOCK_SIZE, &ctx);
+            dec(tmp2, idata + blockno * BLOCK_SIZE, &ctx);
             xorblock(tmp2, tmp);
-            memcpy(output->data + blockno * BLOCK_SIZE, tmp2, BLOCK_SIZE);
-            memcpy(tmp, input->data + blockno * BLOCK_SIZE, BLOCK_SIZE);
+            memcpy(odata + blockno * BLOCK_SIZE, tmp2, BLOCK_SIZE);
+            memcpy(tmp, idata + blockno * BLOCK_SIZE, BLOCK_SIZE);
         }
         /* Do last two blocks, the second of which (next-to-last block
            of plaintext) may be incomplete.  */
-        dec(tmp2, input->data + (nblocks - 2) * BLOCK_SIZE, &ctx);
+        dec(tmp2, idata + (nblocks - 2) * BLOCK_SIZE, &ctx);
         /* Set tmp3 to last ciphertext block, padded.  */
         memset(tmp3, 0, sizeof(tmp3));
-        memcpy(tmp3, input->data + (nblocks - 1) * BLOCK_SIZE,
+        memcpy(tmp3, idata + (nblocks - 1) * BLOCK_SIZE,
                input->length - (nblocks - 1) * BLOCK_SIZE);
         /* Set tmp2 to last (possibly partial) plaintext block, and
            save it.  */
         xorblock(tmp2, tmp3);
-        memcpy(output->data + (nblocks - 1) * BLOCK_SIZE, tmp2,
+        memcpy(odata + (nblocks - 1) * BLOCK_SIZE, tmp2,
                input->length - (nblocks - 1) * BLOCK_SIZE);
         /* Maybe keep the trailing part, and copy in the last
            ciphertext block.  */
@@ -193,10 +166,9 @@ krb5int_aes_decrypt(krb5_key key, const krb5_data *ivec,
            ciphertext.  */
         dec(tmp3, tmp2, &ctx);
         xorblock(tmp3, tmp);
-        memcpy(output->data + (nblocks - 2) * BLOCK_SIZE, tmp3, BLOCK_SIZE);
+        memcpy(odata + (nblocks - 2) * BLOCK_SIZE, tmp3, BLOCK_SIZE);
         if (ivec)
-            memcpy(ivec->data, input->data + (nblocks - 2) * BLOCK_SIZE,
-                   BLOCK_SIZE);
+            memcpy(ivec->data, idata + (nblocks - 2) * BLOCK_SIZE, BLOCK_SIZE);
     }
 
     return 0;
@@ -209,7 +181,7 @@ krb5int_aes_encrypt_iov(krb5_key key,
                         size_t num_data)
 {
     aes_ctx ctx;
-    char tmp[BLOCK_SIZE], tmp2[BLOCK_SIZE];
+    unsigned char tmp[BLOCK_SIZE], tmp2[BLOCK_SIZE];
     int nblocks = 0, blockno;
     size_t input_length, i;
 
@@ -234,20 +206,22 @@ krb5int_aes_encrypt_iov(krb5_key key,
     assert(nblocks > 1);
 
     {
-        char blockN2[BLOCK_SIZE];   /* second last */
-        char blockN1[BLOCK_SIZE];   /* last block */
+        unsigned char blockN2[BLOCK_SIZE];   /* second last */
+        unsigned char blockN1[BLOCK_SIZE];   /* last block */
         struct iov_block_state input_pos, output_pos;
 
         IOV_BLOCK_STATE_INIT(&input_pos);
         IOV_BLOCK_STATE_INIT(&output_pos);
 
         for (blockno = 0; blockno < nblocks - 2; blockno++) {
-            char blockN[BLOCK_SIZE];
+            unsigned char blockN[BLOCK_SIZE];
 
-            krb5int_c_iov_get_block((unsigned char *)blockN, BLOCK_SIZE, data, num_data, &input_pos);
+            krb5int_c_iov_get_block(blockN, BLOCK_SIZE, data, num_data,
+                                    &input_pos);
             xorblock(tmp, blockN);
             enc(tmp2, tmp, &ctx);
-            krb5int_c_iov_put_block(data, num_data, (unsigned char *)tmp2, BLOCK_SIZE, &output_pos);
+            krb5int_c_iov_put_block(data, num_data, tmp2, BLOCK_SIZE,
+                                    &output_pos);
 
             /* Set up for next block.  */
             memcpy(tmp, tmp2, BLOCK_SIZE);
@@ -258,8 +232,10 @@ krb5int_aes_encrypt_iov(krb5_key key,
 
         /* First, get the last two blocks */
         memset(blockN1, 0, sizeof(blockN1)); /* pad last block with zeros */
-        krb5int_c_iov_get_block((unsigned char *)blockN2, BLOCK_SIZE, data, num_data, &input_pos);
-        krb5int_c_iov_get_block((unsigned char *)blockN1, BLOCK_SIZE, data, num_data, &input_pos);
+        krb5int_c_iov_get_block(blockN2, BLOCK_SIZE, data, num_data,
+                                &input_pos);
+        krb5int_c_iov_get_block(blockN1, BLOCK_SIZE, data, num_data,
+                                &input_pos);
 
         /* Encrypt second last block */
         xorblock(tmp, blockN2);
@@ -273,8 +249,10 @@ krb5int_aes_encrypt_iov(krb5_key key,
         memcpy(blockN1, tmp2, BLOCK_SIZE);
 
         /* Put the last two blocks back into the iovec (reverse order) */
-        krb5int_c_iov_put_block(data, num_data, (unsigned char *)blockN1, BLOCK_SIZE, &output_pos);
-        krb5int_c_iov_put_block(data, num_data, (unsigned char *)blockN2, BLOCK_SIZE, &output_pos);
+        krb5int_c_iov_put_block(data, num_data, blockN1, BLOCK_SIZE,
+                                &output_pos);
+        krb5int_c_iov_put_block(data, num_data, blockN2, BLOCK_SIZE,
+                                &output_pos);
 
         if (ivec != NULL)
             memcpy(ivec->data, blockN1, BLOCK_SIZE);
@@ -290,7 +268,7 @@ krb5int_aes_decrypt_iov(krb5_key key,
                         size_t num_data)
 {
     aes_ctx ctx;
-    char tmp[BLOCK_SIZE], tmp2[BLOCK_SIZE], tmp3[BLOCK_SIZE];
+    unsigned char tmp[BLOCK_SIZE], tmp2[BLOCK_SIZE], tmp3[BLOCK_SIZE];
     int nblocks = 0, blockno;
     unsigned int i;
     size_t input_length;
@@ -318,20 +296,22 @@ krb5int_aes_decrypt_iov(krb5_key key,
     assert(nblocks > 1);
 
     {
-        char blockN2[BLOCK_SIZE];   /* second last */
-        char blockN1[BLOCK_SIZE];   /* last block */
+        unsigned char blockN2[BLOCK_SIZE];   /* second last */
+        unsigned char blockN1[BLOCK_SIZE];   /* last block */
         struct iov_block_state input_pos, output_pos;
 
         IOV_BLOCK_STATE_INIT(&input_pos);
         IOV_BLOCK_STATE_INIT(&output_pos);
 
         for (blockno = 0; blockno < nblocks - 2; blockno++) {
-            char blockN[BLOCK_SIZE];
+            unsigned char blockN[BLOCK_SIZE];
 
-            krb5int_c_iov_get_block((unsigned char *)blockN, BLOCK_SIZE, data, num_data, &input_pos);
+            krb5int_c_iov_get_block(blockN, BLOCK_SIZE, data, num_data,
+                                    &input_pos);
             dec(tmp2, blockN, &ctx);
             xorblock(tmp2, tmp);
-            krb5int_c_iov_put_block(data, num_data, (unsigned char *)tmp2, BLOCK_SIZE, &output_pos);
+            krb5int_c_iov_put_block(data, num_data, tmp2, BLOCK_SIZE,
+                                    &output_pos);
             memcpy(tmp, blockN, BLOCK_SIZE);
         }
 
@@ -340,8 +320,10 @@ krb5int_aes_decrypt_iov(krb5_key key,
 
         /* First, get the last two encrypted blocks */
         memset(blockN1, 0, sizeof(blockN1)); /* pad last block with zeros */
-        krb5int_c_iov_get_block((unsigned char *)blockN2, BLOCK_SIZE, data, num_data, &input_pos);
-        krb5int_c_iov_get_block((unsigned char *)blockN1, BLOCK_SIZE, data, num_data, &input_pos);
+        krb5int_c_iov_get_block(blockN2, BLOCK_SIZE, data, num_data,
+                                &input_pos);
+        krb5int_c_iov_get_block(blockN1, BLOCK_SIZE, data, num_data,
+                                &input_pos);
 
         if (ivec != NULL)
             memcpy(ivec->data, blockN2, BLOCK_SIZE);
@@ -362,8 +344,10 @@ krb5int_aes_decrypt_iov(krb5_key key,
         memcpy(blockN1, tmp3, BLOCK_SIZE);
 
         /* Put the last two blocks back into the iovec */
-        krb5int_c_iov_put_block(data, num_data, (unsigned char *)blockN1, BLOCK_SIZE, &output_pos);
-        krb5int_c_iov_put_block(data, num_data, (unsigned char *)blockN2, BLOCK_SIZE, &output_pos);
+        krb5int_c_iov_put_block(data, num_data, blockN1, BLOCK_SIZE,
+                                &output_pos);
+        krb5int_c_iov_put_block(data, num_data, blockN2, BLOCK_SIZE,
+                                &output_pos);
     }
 
     return 0;
@@ -374,7 +358,7 @@ krb5int_aes_init_state (const krb5_keyblock *key, krb5_keyusage usage,
                         krb5_data *state)
 {
     state->length = 16;
-    state->data = (void *) malloc(16);
+    state->data = malloc(16);
     if (state->data == NULL)
         return ENOMEM;
     memset(state->data, 0, state->length);