tls: Add internal function ssl_read_application_data()

The function will be used by
mbedtls_ssl_read_early_data() as well.

Signed-off-by: Jerry Yu <jerry.h.yu@arm.com>
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
This commit is contained in:
Jerry Yu 2022-12-08 21:10:25 +08:00 committed by Ronald Cron
parent 5d0ae9021f
commit 739a1d4246

View file

@ -5647,13 +5647,54 @@ static int ssl_handle_hs_message_post_handshake(mbedtls_ssl_context *ssl)
return MBEDTLS_ERR_SSL_INTERNAL_ERROR;
}
/*
* brief Read at most 'len' application data bytes from the input
* buffer.
*
* param ssl SSL context:
* - First byte of application data not read yet in the input
* buffer located at address `in_offt`.
* - The number of bytes of data not read yet is `in_msglen`.
* param buf buffer that will hold the data
* param len maximum number of bytes to read
*
* note The function updates the fields `in_offt` and `in_msglen`
* according to the number of bytes read.
*
* return The number of bytes read.
*/
static int ssl_read_application_data(
mbedtls_ssl_context *ssl, unsigned char *buf, size_t len)
{
size_t n = (len < ssl->in_msglen) ? len : ssl->in_msglen;
if (len != 0) {
memcpy(buf, ssl->in_offt, n);
ssl->in_msglen -= n;
}
/* Zeroising the plaintext buffer to erase unused application data
from the memory. */
mbedtls_platform_zeroize(ssl->in_offt, n);
if (ssl->in_msglen == 0) {
/* all bytes consumed */
ssl->in_offt = NULL;
ssl->keep_current_message = 0;
} else {
/* more data available */
ssl->in_offt += n;
}
return (int) n;
}
/*
* Receive application data decrypted from the SSL layer
*/
int mbedtls_ssl_read(mbedtls_ssl_context *ssl, unsigned char *buf, size_t len)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t n;
if (ssl == NULL || ssl->conf == NULL) {
return MBEDTLS_ERR_SSL_BAD_INPUT_DATA;
@ -5817,30 +5858,11 @@ int mbedtls_ssl_read(mbedtls_ssl_context *ssl, unsigned char *buf, size_t len)
#endif /* MBEDTLS_SSL_PROTO_DTLS */
}
n = (len < ssl->in_msglen)
? len : ssl->in_msglen;
if (len != 0) {
memcpy(buf, ssl->in_offt, n);
ssl->in_msglen -= n;
}
/* Zeroising the plaintext buffer to erase unused application data
from the memory. */
mbedtls_platform_zeroize(ssl->in_offt, n);
if (ssl->in_msglen == 0) {
/* all bytes consumed */
ssl->in_offt = NULL;
ssl->keep_current_message = 0;
} else {
/* more data available */
ssl->in_offt += n;
}
ret = ssl_read_application_data(ssl, buf, len);
MBEDTLS_SSL_DEBUG_MSG(2, ("<= read"));
return (int) n;
return ret;
}
/*