# include <string.h>
# include <openssl/bn.h>
# include <openssl/buffer.h>
+# include <openssl/crypto.h>
# include "e_os.h"
# ifdef __cplusplus
# endif
typedef struct {
- /* Pointer to the start of the buffer data */
- unsigned char *start;
-
- /* Pointer to the first byte after the end of the buffer data */
- unsigned char *end;
-
/* Pointer to where we are currently reading from */
unsigned char *curr;
+ /* Number of bytes remaining */
+ size_t remaining;
} PACKET;
+/* Internal unchecked shorthand; don't use outside this file. */
+static inline void packet_forward(PACKET *pkt, size_t len)
+{
+ pkt->curr += len;
+ pkt->remaining -= len;
+}
+
/*
* Returns the number of bytes remaining to be read in the PACKET
*/
-__owur static inline size_t PACKET_remaining(const PACKET *pkt)
+static inline size_t PACKET_remaining(const PACKET *pkt)
{
- return (size_t)(pkt->end - pkt->curr);
+ return pkt->remaining;
}
/*
* copy of the data so |buf| must be present for the whole time that the PACKET
* is being used.
*/
-static inline int PACKET_buf_init(PACKET *pkt, unsigned char *buf, size_t len)
+__owur static inline int PACKET_buf_init(PACKET *pkt, unsigned char *buf,
+ size_t len)
{
- pkt->start = pkt->curr = buf;
- pkt->end = pkt->start + len;
-
- /* Sanity checks */
- if (pkt->start > pkt->end
- || pkt->curr < pkt->start
- || pkt->curr > pkt->end
- || len != (size_t)(pkt->end - pkt->start)) {
+ /* Sanity check for negative values. */
+ if (len > (size_t)(SIZE_MAX / 2))
return 0;
- }
+ pkt->curr = buf;
+ pkt->remaining = len;
return 1;
}
+/* Initialize a PACKET to hold zero bytes. */
+static inline void PACKET_null_init(PACKET *pkt)
+{
+ pkt->curr = NULL;
+ pkt->remaining = 0;
+}
+
+/*
+ * Returns 1 if the packet has length |num| and its contents equal the |num|
+ * bytes read from |ptr|. Returns 0 otherwise (lengths or contents not equal).
+ * If lengths are equal, performs the comparison in constant time.
+ */
+__owur static inline int PACKET_equal(const PACKET *pkt, const void *ptr,
+ size_t num) {
+ if (PACKET_remaining(pkt) != num)
+ return 0;
+ return CRYPTO_memcmp(pkt->curr, ptr, num) == 0;
+}
+
/*
* Peek ahead and initialize |subpkt| with the next |len| bytes read from |pkt|.
* Data is not copied: the |subpkt| packet will share its underlying buffer with
if (PACKET_remaining(pkt) < len)
return 0;
- PACKET_buf_init(subpkt, pkt->curr, len);
-
- return 1;
+ return PACKET_buf_init(subpkt, pkt->curr, len);
}
/*
if (!PACKET_peek_sub_packet(pkt, subpkt, len))
return 0;
- pkt->curr += len;
+ packet_forward(pkt, len);
return 1;
}
if (!PACKET_peek_net_2(pkt, data))
return 0;
- pkt->curr += 2;
+ packet_forward(pkt, 2);
return 1;
}
if (!PACKET_peek_net_3(pkt, data))
return 0;
- pkt->curr += 3;
+ packet_forward(pkt, 3);
return 1;
}
if (!PACKET_peek_net_4(pkt, data))
return 0;
- pkt->curr += 4;
+ packet_forward(pkt, 4);
return 1;
}
if (!PACKET_peek_1(pkt, data))
return 0;
- pkt->curr++;
+ packet_forward(pkt, 1);
return 1;
}
if (!PACKET_peek_4(pkt, data))
return 0;
- pkt->curr += 4;
+ packet_forward(pkt, 4);
return 1;
}
* underlying buffer gets freed
*/
__owur static inline int PACKET_peek_bytes(const PACKET *pkt, unsigned char **data,
- size_t len)
+ size_t len)
{
if (PACKET_remaining(pkt) < len)
return 0;
if (!PACKET_peek_bytes(pkt, data, len))
return 0;
- pkt->curr += len;
+ packet_forward(pkt, len);
return 1;
}
if (!PACKET_peek_copy_bytes(pkt, data, len))
return 0;
- pkt->curr += len;
+ packet_forward(pkt, len);
return 1;
}
+/*
+ * Copy packet data to |dest|, and set |len| to the number of copied bytes.
+ * If the packet has more than |dest_len| bytes, nothing is copied.
+ * Returns 1 if the packet data fits in |dest_len| bytes, 0 otherwise.
+ * Does not forward PACKET position (because it is typically the last thing
+ * done with a given PACKET).
+ */
+__owur static inline int PACKET_copy_all(const PACKET *pkt, unsigned char *dest,
+ size_t dest_len, size_t *len) {
+ if (PACKET_remaining(pkt) > dest_len) {
+ *len = 0;
+ return 0;
+ }
+ *len = pkt->remaining;
+ memcpy(dest, pkt->curr, pkt->remaining);
+ return 1;
+}
+
/*
* Copy |pkt| bytes to a newly allocated buffer and store a pointer to the
* result in |*data|, and the length in |len|.
__owur static inline int PACKET_strndup(const PACKET *pkt, char **data)
{
OPENSSL_free(*data);
+
+ /* This will succeed on an empty packet, unless pkt->curr == NULL. */
*data = BUF_strndup((const char*)pkt->curr, PACKET_remaining(pkt));
return (*data != NULL);
}
-/* Move the current reading position back |len| bytes */
-__owur static inline int PACKET_back(PACKET *pkt, size_t len)
-{
- if (len > (size_t)(pkt->curr - pkt->start))
- return 0;
-
- pkt->curr -= len;
-
- return 1;
-}
-
/* Move the current reading position forward |len| bytes */
__owur static inline int PACKET_forward(PACKET *pkt, size_t len)
{
if (PACKET_remaining(pkt) < len)
return 0;
- pkt->curr += len;
-
- return 1;
-}
-
-/* Store a bookmark for the current reading position in |*bm| */
-__owur static inline int PACKET_get_bookmark(const PACKET *pkt, size_t *bm)
-{
- *bm = pkt->curr - pkt->start;
-
- return 1;
-}
-
-/* Set the current reading position to the bookmark |bm| */
-__owur static inline int PACKET_goto_bookmark(PACKET *pkt, size_t bm)
-{
- if (bm > (size_t)(pkt->end - pkt->start))
- return 0;
-
- pkt->curr = pkt->start + bm;
-
- return 1;
-}
-
-/*
- * Stores the total length of the packet we have in the underlying buffer in
- * |*len|
- */
-__owur static inline int PACKET_length(const PACKET *pkt, size_t *len)
-{
- *len = pkt->end - pkt->start;
+ packet_forward(pkt, len);
return 1;
}
}
*pkt = tmp;
- subpkt->start = subpkt->curr = data;
- subpkt->end = subpkt->start + length;
+ subpkt->curr = data;
+ subpkt->remaining = length;
return 1;
}
}
*pkt = tmp;
- subpkt->start = subpkt->curr = data;
- subpkt->end = subpkt->start + length;
+ subpkt->curr = data;
+ subpkt->remaining = length;
return 1;
}
}
*pkt = tmp;
- subpkt->start = subpkt->curr = data;
- subpkt->end = subpkt->start + length;
+ subpkt->curr = data;
+ subpkt->remaining = length;
return 1;
}