1 files changed, 129 insertions, 0 deletions
diff --git a/runtime/libgcry_common.c b/runtime/libgcry_common.c
index 49a0e669..63b5e5d5 100644
--- a/runtime/libgcry_common.c
+++ b/runtime/libgcry_common.c
@@ -75,3 +75,132 @@ gcryGetKeyFromFile(char *fn, char **key, unsigned *keylen)
 	r = 0;
 done:	return r;
 }
+
+
+/* execute the child process (must be called in child context
+ * after fork).
+ */
+
+static void
+execKeyScript(char *cmd, int pipefd[])
+{
+	char *newargv[] = { NULL };
+	char *newenviron[] = { NULL };
+
+	dup2(pipefd[0], STDIN_FILENO);
+	dup2(pipefd[1], STDOUT_FILENO);
+
+	/* finally exec child */
+fprintf(stderr, "pre execve: %s\n", cmd);
+	execve(cmd, newargv, newenviron);
+	/* switch to?
+	execlp((char*)program, (char*) program, (char*)arg, NULL);
+	*/
+
+	/* we should never reach this point, but if we do, we terminate */
+done:	return;
+}
+
+
+static int
+openPipe(char *cmd, int *fd)
+{
+	int pipefd[2];
+	pid_t cpid;
+	int r;
+
+	if(pipe(pipefd) == -1) {
+		r = 1; goto done;
+	}
+
+	cpid = fork();
+	if(cpid == -1) {
+		r = 1; goto done;
+	}
+
+	if(cpid == 0) {    
+		/* we are the child */
+		execKeyScript(cmd, pipefd);
+		exit(1);
+	}
+
+	close(pipefd[1]);
+	*fd = pipefd[0];
+	r = 0;
+done:	return r;
+}
+
+
+/* Read a character from the program's output. */
+// TODO: highly unoptimized version, should be used in buffered
+// mode
+static int
+readProgChar(int fd, char *c)
+{
+	int r;
+	if(read(fd, c, 1) != 1) {
+		r = 1; goto done;
+	}
+	r = 0;
+done:	return r;
+}
+
+/* Read a line from the script. Line is terminated by LF, which
+ * is NOT put into the buffer.
+ * buf must be 64KiB
+ */
+static int
+readProgLine(int fd, char *buf)
+{
+	char c;
+	int r;
+	unsigned i;
+	
+	for(i = 0 ; i < 64*1024 ; ++i) {
+		if((r = readProgChar(fd, &c)) != 0) goto done;
+		if(c == '\n')
+			break;
+		buf[i] = c;
+	};
+	if(i >= 64*1024) {
+		r = 1; goto done;
+	}
+	buf[i] = '\0';
+	r = 0;
+done:	return r;
+}
+static int
+readProgKey(int fd, char *buf, unsigned keylen)
+{
+	char c;
+	int r;
+	unsigned i;
+	
+	for(i = 0 ; i < keylen ; ++i) {
+		if((r = readProgChar(fd, &c)) != 0) goto done;
+		buf[i] = c;
+	};
+	r = 0;
+done:	return r;
+}
+
+int 
+gcryGetKeyFromProg(char *cmd, char **key, unsigned *keylen)
+{
+	int r;
+	int fd;
+	char rcvBuf[64*1024];
+
+	if((r = openPipe(cmd, &fd)) != 0) goto done;
+	if((r = readProgLine(fd, rcvBuf)) != 0) goto done;
+	if(strcmp(rcvBuf, "RSYSLOG-KEY-PROVIDER:0")) {
+		r = 2; goto done;
+	}
+	if((r = readProgLine(fd, rcvBuf)) != 0) goto done;
+	*keylen = atoi(rcvBuf);
+	if((*key = malloc(*keylen)) == NULL) {
+		r = -1; goto done;
+	}
+	if((r = readProgKey(fd, *key, *keylen)) != 0) goto done;
+done:	return r;
+}