MINOR: ssl: load certificates in alphabetical order

As reported by Raphaël Enrici, certificates loaded from a directory are loaded
in a non predictive order. If no certificate was first loaded from a file, it
can result in different behaviours when haproxy is used in cluster.
We can also imagine other cases which weren't met yet.

Instead of using readdir(), we can use scandir() and sort files alphabetically.
This will ensure a predictive behaviour.

This patch should also be backported to 1.5.

diff --git a/doc/configuration.txt b/doc/configuration.txt
index 3cf54e466cca1de2b60205ad113aad2c13ee7847..2295744249fd4e2621668a3708c776269e417529 100644 (file)
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -8553,20 +8553,21 @@ crt <cert>
   are loaded.
 
   If a directory name is used instead of a PEM file, then all files found in
-  that directory will be loaded unless their name ends with '.issuer' or
-  '.ocsp' (reserved extensions). This directive may be specified multiple times
-  in order to load certificates from multiple files or directories. The
-  certificates will be presented to clients who provide a valid TLS Server Name
-  Indication field matching one of their CN or alt subjects. Wildcards are
-  supported, where a wildcard character '*' is used instead of the first
-  hostname component (eg: *.example.org matches www.example.org but not
+  that directory will be loaded in alphabetic order unless their name ends with
+  '.issuer' or '.ocsp' (reserved extensions). This directive may be specified
+  multiple times in order to load certificates from multiple files or
+  directories. The certificates will be presented to clients who provide a valid
+  TLS Server Name Indication field matching one of their CN or alt subjects.
+  Wildcards are supported, where a wildcard character '*' is used instead of the
+  first hostname component (eg: *.example.org matches www.example.org but not
   www.sub.example.org).
 
   If no SNI is provided by the client or if the SSL library does not support
   TLS extensions, or if the client provides an SNI hostname which does not
   match any certificate, then the first loaded certificate will be presented.
   This means that when loading certificates from a directory, it is highly
-  recommended to load the default one first as a file.
+  recommended to load the default one first as a file or to ensure that it will
+  always be the first one in the directory.
 
   Note that the same cert may be loaded multiple times without side effects.
 

diff --git a/src/ssl_sock.c b/src/ssl_sock.c
index 67422dc75d37e2f6706a465a56bac6a8deb9edcd..f5642ccea754fff32fcdbfe3da977bc04126da32 100644 (file)
--- a/src/ssl_sock.c
+++ b/src/ssl_sock.c
@@ -1308,7 +1308,8 @@ static int ssl_sock_load_cert_file(const char *path, struct bind_conf *bind_conf
 
 int ssl_sock_load_cert(char *path, struct bind_conf *bind_conf, struct proxy *curproxy, char **err)
 {
-       struct dirent *de;
+       struct dirent **de_list;
+       int i, n;
        DIR *dir;
        struct stat buf;
        char *end;
@@ -1322,21 +1323,34 @@ int ssl_sock_load_cert(char *path, struct bind_conf *bind_conf, struct proxy *cu
        for (end = path + strlen(path) - 1; end >= path && *end == '/'; end--)
                *end = 0;
 
-       while ((de = readdir(dir))) {
-               end = strrchr(de->d_name, '.');
-               if (end && (!strcmp(end, ".issuer") || !strcmp(end, ".ocsp")))
-                       continue;
+       n = scandir(path, &de_list, 0, alphasort);
+       if (n < 0) {
+               memprintf(err, "%sunable to scan directory '%s' : %s.\n",
+                         err && *err ? *err : "", path, strerror(errno));
+               cfgerr++;
+       }
+       else {
+               for (i = 0; i < n; i++) {
+                       struct dirent *de = de_list[i];
 
-               snprintf(fp, sizeof(fp), "%s/%s", path, de->d_name);
-               if (stat(fp, &buf) != 0) {
-                       memprintf(err, "%sunable to stat SSL certificate from file '%s' : %s.\n",
-                                 err && *err ? *err : "", fp, strerror(errno));
-                       cfgerr++;
-                       continue;
+                       end = strrchr(de->d_name, '.');
+                       if (end && (!strcmp(end, ".issuer") || !strcmp(end, ".ocsp")))
+                               goto ignore_entry;
+
+                       snprintf(fp, sizeof(fp), "%s/%s", path, de->d_name);
+                       if (stat(fp, &buf) != 0) {
+                               memprintf(err, "%sunable to stat SSL certificate from file '%s' : %s.\n",
+                                         err && *err ? *err : "", fp, strerror(errno));
+                               cfgerr++;
+                               goto ignore_entry;
+                       }
+                       if (!S_ISREG(buf.st_mode))
+                               goto ignore_entry;
+                       cfgerr += ssl_sock_load_cert_file(fp, bind_conf, curproxy, NULL, 0, err);
+       ignore_entry:
+                       free(de);
                }
-               if (!S_ISREG(buf.st_mode))
-                       continue;
-               cfgerr += ssl_sock_load_cert_file(fp, bind_conf, curproxy, NULL, 0, err);
+               free(de_list);
        }
        closedir(dir);
        return cfgerr;