- (djm) Make EGD failures non-fatal if OpenSSL's entropy pool is still OK

   based on patch from Lutz Jaenicke <Lutz.Jaenicke@aet.TU-Cottbus.DE>

diff --git a/ChangeLog b/ChangeLog
index a41898011eb941f4b25c9acaee90d99a0db55c75..9fd1c78641d39e5b932150ee3d05bb57674c76bc 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -2,6 +2,8 @@
  - (djm) Better fix to aclocal tests from Garrick James <garrick@james.net>
  - (djm) Account expiry support from Andreas Steinmetz <ast@domdv.de>
  - (djm) Added password expiry checking (no password change support)
+ - (djm) Make EGD failures non-fatal if OpenSSL's entropy pool is still OK
+   based on patch from Lutz Jaenicke <Lutz.Jaenicke@aet.TU-Cottbus.DE>
  - OpenBSD CVS update
    - provos@cvs.openbsd.org  2000/06/25 14:17:58
      [channels.c]

diff --git a/README b/README
index c51428849766c3e6f93aecaffa8bfd319817d126..54adb10e574820ed1b94ec7d2092b5cc88de3117 100644 (file)
--- a/README
+++ b/README
@@ -37,9 +37,15 @@ There is now several mailing lists for this port of OpenSSH. Please
 refer to http://www.openssh.com/list.html for details on how to join.
 
 Please send bug reports and patches to the mailing list
-openssh-unix-dev@mindrot.org. The list is currently open to posting by
+openssh-unix-dev@mindrot.org. The list is open to posting by
 unsubscribed users.
 
+If you are a citizen of the USA or another country which restricts 
+export of cryptographic products, then please refrain from sending 
+crypto-related code or patches to the list. We cannot accept them.
+Other code contribution are accepted, but please follow the OpenBSD
+style guidelines[5].
+
 Please refer to the INSTALL document for information on how to install
 OpenSSH on your system. The UPGRADING document details differences 
 between this port of OpenSSH and F-Secure SSH 1.x.
@@ -59,4 +65,5 @@ References -
 [2] ftp://ftp.freesoftware.com/pub/infozip/zlib/
 [3] http://www.openssl.org/
 [4] http://www.kernel.org/pub/linux/libs/pam/ (PAM is standard on Solaris)
+[5] http://www.openbsd.org/cgi-bin/man.cgi?query=style&sektion=9&apropos=0&manpath=OpenBSD+Current
 

diff --git a/entropy.c b/entropy.c
index 0b86fdf0e0cb376d404708f4d5e1998f3d3f1b2e..96e6e85fb247061fcf4748638b316d95419c18b3 100644 (file)
--- a/entropy.c
+++ b/entropy.c
@@ -66,64 +66,83 @@ RCSID("$Id$");
 
 #ifdef EGD_SOCKET
 /* Collect entropy from EGD */
-void get_random_bytes(unsigned char *buf, int len)
+int get_random_bytes(unsigned char *buf, int len)
 {
-       static int egd_socket = -1;
-       int c;
-       char egd_message[2] = { 0x02, 0x00 };
+       int fd;
+       char msg[2];
        struct sockaddr_un addr;
        int addr_len;
 
-       memset(&addr, '\0', sizeof(addr));
-       addr.sun_family = AF_UNIX;
-       
-       /* FIXME: compile time check? */
+       /* Sanity checks */
        if (sizeof(EGD_SOCKET) > sizeof(addr.sun_path))
                fatal("Random pool path is too long");
-       
+       if (len > 255)
+               fatal("Too many bytes to read from EGD");
+
+       memset(&addr, '\0', sizeof(addr));
+       addr.sun_family = AF_UNIX;
        strlcpy(addr.sun_path, EGD_SOCKET, sizeof(addr.sun_path));
-       
        addr_len = offsetof(struct sockaddr_un, sun_path) + sizeof(EGD_SOCKET);
        
-       if (egd_socket == -1) {
-               egd_socket = socket(AF_UNIX, SOCK_STREAM, 0);
-               if (egd_socket == -1)
-                       fatal("Couldn't create AF_UNIX socket: %s", strerror(errno));
-               if (connect(egd_socket, (struct sockaddr*)&addr, addr_len) == -1)
-                       fatal("Couldn't connect to EGD socket \"%s\": %s", addr.sun_path, strerror(errno));
-       }       
+       fd = socket(AF_UNIX, SOCK_STREAM, 0);
+       if (fd == -1) {
+               error("Couldn't create AF_UNIX socket: %s", strerror(errno));
+               return(0);
+       }
+
+       if (connect(fd, (struct sockaddr*)&addr, addr_len) == -1) {
+               error("Couldn't connect to EGD socket \"%s\": %s", 
+                       addr.sun_path, strerror(errno));
+               close(fd);
+               return(0);
+       }
 
-       if (len > 255)
-               fatal("Too many bytes to read from EGD");
-       
        /* Send blocking read request to EGD */
-       egd_message[1] = len;
+       msg[0] = 0x02;
+       msg[1] = len;
 
-       c = atomicio(write, egd_socket, egd_message, sizeof(egd_message));
-       if (c == -1)
-               fatal("Couldn't write to EGD socket \"%s\": %s", EGD_SOCKET, strerror(errno));
+       if (atomicio(write, fd, msg, sizeof(msg)) != sizeof(msg)) {
+               error("Couldn't write to EGD socket \"%s\": %s", 
+                       EGD_SOCKET, strerror(errno));
+               close(fd);
+               return(0);
+       }
 
-       c = atomicio(read, egd_socket, buf, len);
-       if (c <= 0)
-               fatal("Couldn't read from EGD socket \"%s\": %s", EGD_SOCKET, strerror(errno));
+       if (atomicio(read, fd, buf, len) != len) {
+               error("Couldn't read from EGD socket \"%s\": %s", 
+                       EGD_SOCKET, strerror(errno));
+               close(fd);
+               return(0);
+       }
+       
+       close(fd);
+       
+       return(1);
 }
 #else /* !EGD_SOCKET */
 #ifdef RANDOM_POOL
 /* Collect entropy from /dev/urandom or pipe */
-void get_random_bytes(unsigned char *buf, int len)
+int get_random_bytes(unsigned char *buf, int len)
 {
-       static int random_pool = -1;
-       int c;
+       int random_pool;
 
+       random_pool = open(RANDOM_POOL, O_RDONLY);
        if (random_pool == -1) {
-               random_pool = open(RANDOM_POOL, O_RDONLY);
-               if (random_pool == -1)
-                       fatal("Couldn't open random pool \"%s\": %s", RANDOM_POOL, strerror(errno));
+               error("Couldn't open random pool \"%s\": %s", 
+                       RANDOM_POOL, strerror(errno));
+               return(0);
        }
        
-       c = atomicio(read, random_pool, buf, len);
-       if (c <= 0)
-               fatal("Couldn't read from random pool \"%s\": %s", RANDOM_POOL, strerror(errno));
+       if (atomicio(read, random_pool, buf, len) != len) {
+               error("Couldn't read from random pool \"%s\": %s", 
+                       RANDOM_POOL, strerror(errno));
+               close(random_pool);
+               return(0);
+       }
+       
+       close(random_pool);
+       
+       return(1);
 }
 #endif /* RANDOM_POOL */
 #endif /* EGD_SOCKET */
@@ -138,8 +157,12 @@ seed_rng(void)
        char buf[32];
        
        debug("Seeding random number generator");
-       get_random_bytes(buf, sizeof(buf));
+
+       if (!get_random_bytes(buf, sizeof(buf)) && !RAND_status())
+               fatal("Entropy collection failed and entropy exhausted");
+
        RAND_add(buf, sizeof(buf), sizeof(buf));
+
        memset(buf, '\0', sizeof(buf));
 }