On 09/15/2011 09:53 PM, [email protected] wrote: > Author: sf > Date: Thu Sep 15 19:53:59 2011 > New Revision: 1171247 > > URL: http://svn.apache.org/viewvc?rev=1171247&view=rev > Log: > Create wrapper API for apr_random; > use in mod_lbmethod_heartbeat and mod_serf to > - replace some needles use of apr_generate_random_bytes > - remove code duplication > > Modified: > httpd/httpd/trunk/CHANGES > httpd/httpd/trunk/include/ap_mmn.h > httpd/httpd/trunk/include/httpd.h > httpd/httpd/trunk/include/mod_core.h > httpd/httpd/trunk/modules/http/http_core.c > httpd/httpd/trunk/modules/proxy/balancers/mod_lbmethod_heartbeat.c > httpd/httpd/trunk/modules/proxy/mod_serf.c > httpd/httpd/trunk/server/core.c >
> Modified: httpd/httpd/trunk/server/core.c > URL: > http://svn.apache.org/viewvc/httpd/httpd/trunk/server/core.c?rev=1171247&r1=1171246&r2=1171247&view=diff > ============================================================================== > --- httpd/httpd/trunk/server/core.c (original) > +++ httpd/httpd/trunk/server/core.c Thu Sep 15 19:53:59 2011 > @@ -20,6 +20,7 @@ > #include "apr_fnmatch.h" > #include "apr_hash.h" > #include "apr_thread_proc.h" /* for RLIMIT stuff */ > +#include "apr_random.h" > > #define APR_WANT_IOVEC > #define APR_WANT_STRFUNC > @@ -4593,12 +4594,93 @@ AP_DECLARE(int) ap_state_query(int query > } > } > > +static apr_random_t *rng = NULL; > +#if APR_HAS_THREADS > +static apr_thread_mutex_t *rng_mutex = NULL; > + > +static void create_rng_mutex(apr_pool_t *pchild, server_rec *s) > +{ > + int threaded_mpm; > + if (ap_mpm_query(AP_MPMQ_IS_THREADED, &threaded_mpm) != APR_SUCCESS) > + return; > + if (threaded_mpm) > + apr_thread_mutex_create(&rng_mutex, APR_THREAD_MUTEX_DEFAULT, > pchild); Shouldn't we use ap_mutex API here to let the user configure the mutex method? > +} > +#endif > + > +static void rng_init(apr_pool_t *p) > +{ > + unsigned char seed[8]; > + apr_status_t rv; > + rng = apr_random_standard_new(p); > + do { > + rv = apr_generate_random_bytes(seed, sizeof(seed)); > + if (rv != APR_SUCCESS) > + goto error; > + apr_random_add_entropy(rng, seed, sizeof(seed)); > + rv = apr_random_insecure_ready(rng); > + } while (rv == APR_ENOTENOUGHENTROPY); > + if (rv == APR_SUCCESS) > + return; > +error: > + ap_log_error(APLOG_MARK, APLOG_CRIT, rv, NULL, > + "Could not initialize random number generator"); > + exit(1); > +} > + > +APR_DECLARE(void) ap_random_insecure_bytes(void *buf, apr_size_t size) > +{ > +#if APR_HAS_THREADS > + if (rng_mutex) > + apr_thread_mutex_lock(rng_mutex); > +#endif > + /* apr_random_insecure_bytes can only fail with APR_ENOTENOUGHENTROPY, > + * and we have ruled that out during initialization. Therefore we don't > + * need to check the return code. > + */ > + apr_random_insecure_bytes(rng, buf, size); > +#if APR_HAS_THREADS > + if (rng_mutex) > + apr_thread_mutex_unlock(rng_mutex); > +#endif > +} > + > +/* > + * Finding a random number in a range. > + * n' = a + n(b-a+1)/(M+1) > + * where: > + * n' = random number in range > + * a = low end of range > + * b = high end of range > + * n = random number of 0..M > + * M = maxint > + * Algorithm 'borrowed' from PHP's rand() function. > + */ > +#define RAND_RANGE(__n, __min, __max, __tmax) \ > +(__n) = (__min) + (long) ((double) ((__max) - (__min) + 1.0) * ((__n) / > ((__tmax) + 1.0))) Is long correct here or shouldn't it be apr_uint32_t? > +APR_DECLARE(apr_uint32_t) ap_random_pick(apr_uint32_t min, apr_uint32_t max) > +{ > + apr_uint32_t number; > + if (max < 16384) { > + apr_uint16_t num16; > + ap_random_insecure_bytes(&num16, sizeof(num16)); > + RAND_RANGE(num16, min, max, APR_UINT16_MAX); > + number = num16; > + } > + else { > + ap_random_insecure_bytes(&number, sizeof(number)); > + RAND_RANGE(number, min, max, APR_UINT32_MAX); > + } > + return number; > +} > + > static void register_hooks(apr_pool_t *p) > { > errorlog_hash = apr_hash_make(p); > ap_register_log_hooks(p); > ap_register_config_hooks(p); > ap_expr_init(p); > + rng_init(p); > > /* create_connection and pre_connection should always be hooked > * APR_HOOK_REALLY_LAST by core to give other modules the opportunity Regards Rüdiger
