diff options
Diffstat (limited to 'cipher/rndw32.c')
| -rw-r--r-- | cipher/rndw32.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/cipher/rndw32.c b/cipher/rndw32.c index eff02078a..b8a1aaf24 100644 --- a/cipher/rndw32.c +++ b/cipher/rndw32.c @@ -53,6 +53,17 @@ #define PCP_DLL_FUNC 8 #define PCP_UNKNOWN_SEEDER_TYPE 9 + +/**************** + * We sometimes get a SEEDER_TOO_SMALL error, in which case we increment + * the internal buffer by SEEDER_INC_CHUNK until we reach MAX_SEEDER_SIZE + * MAX_SEEDER_SIZE is used as an arbitrary limit to protect against + * bugs in Winseed. + */ +#define MAX_SEEDER_SIZE 500000 +#define SEEDER_INC_CHUNK 50000 + + typedef void *WIN32_SEEDER; static WIN32_SEEDER (WINAPI *create_instance)( byte type, unsigned int *reason); @@ -172,6 +183,25 @@ gather_random( void (*add)(const void*, size_t, int), int requester, for(;;) { nbytes = entropy_buffer_size; result = get_seed( slow_seeder, entropy_buffer, &nbytes); + if( result == PCP_SEEDER_TOO_SMALL ) { + unsigned int n1 = get_internal_seed_size( slow_seeder ); + + if( n1 > MAX_SEEDER_SIZE ) { + g10_log_fatal("rndw32: internal seeder problem (size=%u)\n", + n1); + return -1; /* actually never reached */ + } + n1 += SEEDER_INC_CHUNK; + set_internal_seed_size( slow_seeder, n1 ); + if( n1 > entropy_buffer_size ) { + entropy_buffer_size = n1; + entropy_buffer = m_realloc( entropy_buffer, + entropy_buffer_size ); + } + continue; + } + + if( result ) { g10_log_fatal("rndw32: get_seed(slow) failed: rc=%u\n", result); return -1; /* actually never reached */ |