X-Git-Url: https://ruderich.org/simon/gitweb/?a=blobdiff_plain;f=src%2Fverify.c;h=e3a86294755c4283bc3c899a03b72501659b61f3;hb=e279b81dba5901ad6ed7fa73901acab10f1d4a63;hp=5248dd6cd243dff33609066f3da00c0c3a6bf5ce;hpb=64bfebde76d568808b6fa8a8d09b4b5afe13dc15;p=tlsproxy%2Ftlsproxy.git

diff --git a/src/verify.c b/src/verify.c
index 5248dd6..e3a8629 100644
--- a/src/verify.c
+++ b/src/verify.c
@@ -155,8 +155,42 @@ int verify_tls_connection(gnutls_session_t session, const char *hostname) {
     return 0;
 }
 
+
+int proxy_certificate_path(const char *hostname, char *path, size_t size) {
+    int result;
+
+    /* Hostname too long. */
+    if (size - strlen(PROXY_SERVER_CERT_FORMAT) <= strlen(hostname)) {
+        LOG(LOG_WARNING,
+            "proxy_certificate_path(): hostname too long: '%s'",
+            hostname);
+        return -1;
+    }
+    /* Try to prevent path traversals in hostnames. */
+    if (NULL != strstr(hostname, "..")) {
+        LOG(LOG_WARNING,
+            "proxy_certificate_path(): possible path traversal: '%s'",
+            hostname);
+        return -1;
+    }
+    result = snprintf(path, size, PROXY_SERVER_CERT_FORMAT, hostname);
+    if (result < 0) {
+        LOG_PERROR(LOG_ERROR,
+                   "proxy_certificate_path(): snprintf failed");
+        return -1;
+    } else if ((size_t)result >= size) {
+        LOG(LOG_ERROR,
+            "proxy_certificate_path(): snprintf buffer too short");
+        return -1;
+    }
+
+    return 0;
+}
+
 int server_certificate_path(FILE **file, const char *hostname,
                             char *path, size_t size) {
+    int result;
+
     /* Hostname too long. */
     if (size - strlen(STORED_SERVER_CERT_FORMAT) <= strlen(hostname)) {
         LOG(LOG_WARNING,
@@ -171,7 +205,16 @@ int server_certificate_path(FILE **file, const char *hostname,
             hostname);
         return -1;
     }
-    snprintf(path, size, STORED_SERVER_CERT_FORMAT, hostname);
+    result = snprintf(path, size, STORED_SERVER_CERT_FORMAT, hostname);
+    if (result < 0) {
+        LOG_PERROR(LOG_ERROR,
+                   "server_certificate_path(): snprintf failed");
+        return -1;
+    } else if ((size_t)result >= size) {
+        LOG(LOG_ERROR,
+            "server_certificate_path(): snprintf buffer too short");
+        return -1;
+    }
 
     /* Open the stored certificate file. */
     *file = fopen(path, "rb");