Third time lucky

[openssh.git] / helper.c

diff --git a/helper.c b/helper.c
index 28fe04219d5b0a1369d4d3e0d37072fb8cb8f699..bf4e145b27a0630d475764c72275723800b4015b 100644 (file)
--- a/helper.c
+++ b/helper.c
@@ -45,7 +45,6 @@
 #include <sys/un.h>
 #include <fcntl.h>
 
-#include "rc4.h"
 #include "xmalloc.h"
 #include "ssh.h"
 #include "config.h"
@@ -57,10 +56,58 @@
 
 #ifndef HAVE_ARC4RANDOM
 
+typedef struct
+{
+       unsigned int s[256];
+       int i;
+       int j;
+} rc4_t;
+
 void get_random_bytes(unsigned char *buf, int len);
+void rc4_key(rc4_t *r, unsigned char *key, int len);
+void rc4_getbytes(rc4_t *r, unsigned char *buffer, int len);
 
 static rc4_t *rc4 = NULL;
 
+void rc4_key(rc4_t *r, unsigned char *key, int len)
+{
+       int t;
+       
+       for(r->i = 0; r->i < 256; r->i++)
+               r->s[r->i] = r->i;
+
+       r->j = 0;
+       for(r->i = 0; r->i < 256; r->i++)
+       {
+               r->j = (r->j + r->s[r->i] + key[r->i % len]) % 256;
+               t = r->s[r->i];
+               r->s[r->i] = r->s[r->j];
+               r->s[r->j] = t;
+       }
+       r->i = r->j = 0;
+}
+
+void rc4_getbytes(rc4_t *r, unsigned char *buffer, int len)
+{
+       int t;
+       int c;
+
+       c = 0;  
+       while(c < len)
+       {
+               r->i = (r->i + 1) % 256;
+               r->j = (r->j + r->s[r->i]) % 256;
+               t = r->s[r->i];
+               r->s[r->i] = r->s[r->j];
+               r->s[r->j] = t;
+
+               t = (r->s[r->i] + r->s[r->j]) % 256;
+               
+               buffer[c] = r->s[t];
+               c++;
+       }
+}
+
 unsigned int arc4random(void)
 {
        unsigned int r;
@@ -100,8 +147,7 @@ void get_random_bytes(unsigned char *buf, int len)
        if (sizeof(RANDOM_POOL) > sizeof(addr.sun_path))
                fatal("Random pool path is too long");
        
-       strncpy(addr.sun_path, RANDOM_POOL, sizeof(addr.sun_path - 1));
-       addr.sun_path[sizeof(addr.sun_path - 1)] = '\0';
+       strcpy(addr.sun_path, RANDOM_POOL);
        
        addr_len = offsetof(struct sockaddr_un, sun_path) + sizeof(RANDOM_POOL);
        
@@ -118,7 +164,8 @@ void get_random_bytes(unsigned char *buf, int len)
        
        /* Send blocking read request to EGD */
        egd_message[1] = len;
-       c = write(random_pool, egd_message, sizeof(egd_message));
+
+       c = atomicio(write, random_pool, egd_message, sizeof(egd_message));
        if (c == -1)
                fatal("Couldn't write to EGD socket \"%s\": %s", RANDOM_POOL, strerror(errno));
 
@@ -130,12 +177,9 @@ void get_random_bytes(unsigned char *buf, int len)
 
 #endif /* HAVE_EGD */
 
-       c = read(random_pool, buf, len);
-       if (c == -1)
+       c = atomicio(read, random_pool, buf, len);
+       if (c <= 0)
                fatal("Couldn't read from random pool \"%s\": %s", RANDOM_POOL, strerror(errno));
-
-       if (c != len)
-               fatal("Short read from random pool \"%s\"", RANDOM_POOL);
        
        close(random_pool);
 }
@@ -147,3 +191,24 @@ void setproctitle(const char *fmt, ...)
        /* FIXME */
 }
 #endif /* !HAVE_SETPROCTITLE */
+
+#ifndef HAVE_SETENV
+int setenv(const char *name, const char *value, int overwrite)
+{
+       char *env_string;
+       int result;
+       
+       /* Don't overwrite existing env. var if overwrite is 0 */
+       if (!overwrite && (getenv(name) != NULL))
+               return(0);
+       
+       env_string = xmalloc(strlen(name) + strlen(value) + 2);
+       sprintf(env_string, "%s=%s", name, value);
+       
+       result = putenv(env_string);
+       
+       xfree(env_string);
+       
+       return(result); 
+}
+#endif /* !HAVE_SETENV */