From 81edd235b143c69a1a7a05149fc94647ab25c89d Mon Sep 17 00:00:00 2001 From: =?utf8?q?Bodo=20M=C3=B6ller?= Date: Wed, 28 Jun 2006 14:49:39 +0000 Subject: [PATCH] always read if we can't use select because of a too large FD (it's non-blocking mode anyway) --- CHANGES | 2 +- crypto/rand/rand_unix.c | 141 ++++++++++++++++++++-------------------- 2 files changed, 72 insertions(+), 71 deletions(-) diff --git a/CHANGES b/CHANGES index 8ca7b0b87d..f2d42a2847 100644 --- a/CHANGES +++ b/CHANGES @@ -7,7 +7,7 @@ *) Change the Unix randomness entropy gathering to use poll() when possible instead of select(), since the latter has some undesirable limitations. - [Darryl Miles via Richard Levitte] + [Darryl Miles via Richard Levitte and Bodo Moeller] *) Disable rogue ciphersuites: diff --git a/crypto/rand/rand_unix.c b/crypto/rand/rand_unix.c index bb0e719201..89e65abe9d 100644 --- a/crypto/rand/rand_unix.c +++ b/crypto/rand/rand_unix.c @@ -56,7 +56,7 @@ * [including the GNU Public Licence.] */ /* ==================================================================== - * Copyright (c) 1998-2000 The OpenSSL Project. All rights reserved. + * Copyright (c) 1998-2006 The OpenSSL Project. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions @@ -124,53 +124,12 @@ #include #include #include - #if defined(OPENSSL_SYS_LINUX) - /* lets use poll() */ # include -# define IOWAIT_VARS struct pollfd pset; struct timeval t -# define IOWAIT_INIT(f, t) do { \ - pset.fd = (f); \ - pset.events = POLLIN; \ - pset.revents = 0; \ - (t)->tv_sec = 0; \ - (t)->tv_usec = 10*1000; \ - /* Spend 10ms on each file. */ \ - } while(0) -# define IOWAIT_FUNC(f, t) poll(&pset, 1, ((t)->tv_sec * 1000) + ((t)->tv_usec / 1000)) -# define IOWAIT_CHECK(f) ((pset.revents & POLLIN) != 0) -#else - /* lets use select() */ - - /* For each platform we could do with making a guess at - * how many FDs we support. With glibc/Linux its possible - * to use FD_SETSIZE directly, but this may not be very - * portable. Another options was to use _POSIX_OPEN_MAX - * but that value is a tad dull on modern hardware. So - * I ended up trying sizeof(fd_set)*8 which should be - * closer to the real value. - * If this causes a problem on your platform because we - * can not guess correctly then set it to zero. - */ -# if defined(FD_SETSIZE) -# define IOWAIT_FD_SETSIZE (FD_SETSIZE) -# else - /* fallback method */ -# define IOWAIT_FD_SETSIZE (sizeof(fd_set) * 8) -# endif -# define IOWAIT_VARS fd_set fset; struct timeval t -# define IOWAIT_INIT(f, t) do { \ - FD_ZERO(&fset); \ - if(IOWAIT_FD_SETSIZE > 0 \ - && (f) >= IOWAIT_FD_SETSIZE) \ - { break; } \ - FD_SET((f), &fset); \ - (t)->tv_sec = 0; \ - (t)->tv_usec = 10*1000; \ - /* Spend 10ms on each file. */ \ - } while(0) -# define IOWAIT_FUNC(f, t) select((f)+1,&fset,NULL,NULL,(t)) -# define IOWAIT_CHECK(f) FD_ISSET((f), &fset) +#endif +#include +#ifndef FD_SETSIZE +# define FD_SETSIZE (8*sizeof(fd_set)) #endif #ifdef __OpenBSD__ @@ -190,7 +149,7 @@ int RAND_poll(void) return 1; } -#else +#else /* !defined(__OpenBSD__) */ int RAND_poll(void) { unsigned long l; @@ -230,8 +189,8 @@ int RAND_poll(void) #endif )) >= 0) { + int usec = 10*1000; /* spend 10ms on each file */ int r,j; - IOWAIT_VARS; struct stat *st=&randomstats[i]; /* Avoid using same input... Used to be O_NOFOLLOW @@ -247,34 +206,75 @@ int RAND_poll(void) do { - r = -1; - IOWAIT_INIT(fd, &t); + int try_read = 0; + +#if defined(OPENSSL_SYS_LINUX) + /* use poll() */ + struct pollfd pset; + + pset.fd = fd; + pset.events = POLLIN; + pset.revents = 0; - if (IOWAIT_FUNC(fd, &t) < 0) - t.tv_usec=0; - else if (IOWAIT_CHECK(fd)) + if (poll(&pset, 1, usec / 1000) < 0) + usec = 0; + else + try_read = (pset.revents & POLLIN) != 0; + +#else + /* use select() */ + fd_set fset; + struct timeval t; + + t.tv_sec = 0; + t.tv_usec = usec; + + if (FD_SETSIZE > 0 && fd >= FD_SETSIZE) { - r=read(fd,(unsigned char *)tmpbuf+n, - ENTROPY_NEEDED-n); + /* can't use select, so just try to read once anyway */ + try_read = 1; + } + else + { + FD_ZERO(&fset); + FD_SET(fd, &fset); + + if (select(fd+1,&fset,NULL,NULL,&t) >= 0) + { + usec = t.tv_usec; + if (FD_ISSET(fd, &fset)) + try_read = 1; + } + else + usec = 0; + } +#endif + + if (try_read) + { + r = read(fd,(unsigned char *)tmpbuf+n, ENTROPY_NEEDED-n); if (r > 0) n += r; } - - /* Some Unixen will update t, some - won't. For those who won't, give - up here, otherwise, we will do + else + r = -1; + + /* Some Unixen will update t in select(), some + won't. For those who won't, or if we + didn't use select() in the first place, + give up here, otherwise, we will do this once again for the remaining time. */ - if (t.tv_usec == 10*1000) - t.tv_usec=0; + if (usec == 10*1000) + usec = 0; } - while ((r > 0 || (errno == EINTR || errno == EAGAIN)) - && t.tv_usec != 0 && n < ENTROPY_NEEDED); + while ((r > 0 || + (errno == EINTR || errno == EAGAIN)) && usec != 0 && n < ENTROPY_NEEDED); close(fd); } } -#endif +#endif /* defined(DEVRANDOM) */ #ifdef DEVRANDOM_EGD /* Use an EGD socket to read entropy from an EGD or PRNGD entropy @@ -289,7 +289,7 @@ int RAND_poll(void) if (r > 0) n += r; } -#endif +#endif /* defined(DEVRANDOM_EGD) */ #if defined(DEVRANDOM) || defined(DEVRANDOM_EGD) if (n > 0) @@ -315,12 +315,13 @@ int RAND_poll(void) #endif } -#endif -#endif +#endif /* defined(__OpenBSD__) */ +#endif /* !(defined(OPENSSL_SYS_WINDOWS) || defined(OPENSSL_SYS_WIN32) || defined(OPENSSL_SYS_VMS) || defined(OPENSSL_SYS_OS2) || defined(OPENSSL_SYS_VXWORKS) */ + #if defined(OPENSSL_SYS_VXWORKS) int RAND_poll(void) -{ - return 0; -} + { + return 0; + } #endif -- 2.25.1