From 5267447126d67bc9309f75e5244761c25254253b Mon Sep 17 00:00:00 2001 From: Bob Beck Date: Sun, 16 Apr 2000 04:47:07 +0000 Subject: Fix this for the case where the file is a device - make sure we don't attempt to read from a device forever. --- lib/libssl/src/crypto/rand/randfile.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) (limited to 'lib') diff --git a/lib/libssl/src/crypto/rand/randfile.c b/lib/libssl/src/crypto/rand/randfile.c index 9ff3974cc7d..4a994bf73b4 100644 --- a/lib/libssl/src/crypto/rand/randfile.c +++ b/lib/libssl/src/crypto/rand/randfile.c @@ -97,13 +97,22 @@ int RAND_load_file(const char *file, long bytes) if (file == NULL) return(0); i=stat(file,&sb); - /* If the state fails, put some crap in anyway */ - RAND_add(&sb,sizeof(sb),0); - if (i < 0) return(0); + if (i < 0) { + /* If the state fails, put some crap in anyway */ + RAND_add(&sb,sizeof(sb),0); + return(0); + } if (bytes == 0) return(ret); - in=fopen(file,"rb"); if (in == NULL) goto err; + if (sb.st_mode & (S_IFBLK | S_IFCHR)) { + /* this file is a device. we don't want read an infinite number + * of bytes from a random device, nor do we want to use buffered + * I/O because we will waste system entropy. + */ + bytes = (bytes == -1) ? 2048 : bytes; /* ok, is 2048 enough? */ + setvbuf(in, NULL, _IONBF, 0); /* don't do buffered reads */ + } for (;;) { if (bytes > 0) @@ -118,7 +127,7 @@ int RAND_load_file(const char *file, long bytes) if (bytes > 0) { bytes-=n; - if (bytes == 0) break; + if (bytes <= 0) break; } } fclose(in); -- cgit v1.2.3