cuberite/polarssl
1
0
Fork 0
mirror of https://github.com/cuberite/polarssl.git synced 2025-10-30 03:00:21 -04:00
Code Issues Packages Projects Releases Wiki Activity

Minor changes to comments in hkdf.c

Browse Source
This commit is contained in:
Brian J Murray 2018-07-06 10:02:39 -07:00 committed by Brian Murray
parent 1ab9b57148
commit a61d123e0e
1 changed files with 9 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
library/hkdf.c
View File

@ -114,6 +114,10 @@ int mbedtls_hkdf_expand( const mbedtls_md_info_t *md, const unsigned char *prk,
n++; n++;
} }
/*
* Per RFC 5869 Section 2.3, okm_len must not exceed
* 255 times the hash length
*/
if( n > 255 ) if( n > 255 )
{ {
return( MBEDTLS_ERR_HKDF_BAD_INPUT_DATA ); return( MBEDTLS_ERR_HKDF_BAD_INPUT_DATA );
@ -126,7 +130,10 @@ int mbedtls_hkdf_expand( const mbedtls_md_info_t *md, const unsigned char *prk,
goto exit; goto exit;
} }
/* RFC 5869 Section 2.3. */ /*
* Compute T = T(1) | T(2) | T(3) | ... | T(N)
* Where T(N) is defined in RFC 5869 Section 2.3
*/
for( i = 1; i <= n; i++ ) for( i = 1; i <= n; i++ )
{ {
size_t num_to_copy; size_t num_to_copy;
@ -150,7 +157,7 @@ int mbedtls_hkdf_expand( const mbedtls_md_info_t *md, const unsigned char *prk,
goto exit; goto exit;
} }
/* The constant concatenated to the end of each t(n) is a single octet. /* The constant concatenated to the end of each T(n) is a single octet.
* */ * */
ret = mbedtls_md_hmac_update( &ctx, &c, 1 ); ret = mbedtls_md_hmac_update( &ctx, &c, 1 );
if( ret != 0 ) if( ret != 0 )