commit 039e02df2716a0ed886b56e1e07b7ac1d8597228
author Jerome Forissier <jerome.forissier@linaro.org> Tue Aug 09 17:10:15 2022 +0200
committer Jérôme Forissier <jerome@forissier.org> Wed Aug 10 20:49:06 2022 +0200
tree 9793d39492b08783ff934ba9065a969bbea85c1b
parent 207505051c368276555a20587449d9fe88e6ac31

Squashed commit upgrading to mbedtls-2.28.1

Squash merging branch import/mbedtls-2.28.1

 ebf1f6a58089 ("libmbedtls: compile new files added with 2.28.1")
 3ffb51b58a54 ("libmbedtls: add SM2 curve")
 c425755720b4 ("libmbedtls: mbedtls_mpi_exp_mod(): optimize mempool usage")
 23493c822a82 ("libmbedtls: mbedtls_mpi_exp_mod(): reduce stack usage")
 dcdca2348dff ("libmbedtls: mbedtls_mpi_exp_mod() initialize W")
 dc2994976958 ("libmbedtls: fix no CRT issue")
 c6628873b281 ("libmbedtls: add interfaces in mbedtls for context memory operation")
 8acd202d3e55 ("libmedtls: mpi_miller_rabin: increase count limit")
 37284e28d5d9 ("libmbedtls: add mbedtls_mpi_init_mempool()")
 b499a75f29f3 ("libmbedtls: make mbedtls_mpi_mont*() available")
 2080a8c96a5d ("mbedtls: configure mbedtls to reach for config")
 e0858334327a ("mbedtls: remove default include/mbedtls/config.h")
 dd9688e6b8ce ("Import mbedtls-2.28.1")

Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org>
Acked-by: Jens Wiklander <jens.wiklander@linaro.org>

lib/libmbedtls/mbedtls/library/x509.c

diff --git a/lib/libmbedtls/mbedtls/library/x509.c b/lib/libmbedtls/mbedtls/library/x509.c
index f21e9e6..3997ebd 100644
--- a/lib/libmbedtls/mbedtls/library/x509.c
+++ b/lib/libmbedtls/mbedtls/library/x509.c
@@ -741,7 +741,7 @@
 int mbedtls_x509_dn_gets( char *buf, size_t size, const mbedtls_x509_name *dn )
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-    size_t i, n;
+    size_t i, j, n;
     unsigned char c, merge = 0;
     const mbedtls_x509_name *name;
     const char *short_name = NULL;
@@ -775,17 +775,24 @@
             ret = mbedtls_snprintf( p, n, "\?\?=" );
         MBEDTLS_X509_SAFE_SNPRINTF;
 
-        for( i = 0; i < name->val.len; i++ )
+        for( i = 0, j = 0; i < name->val.len; i++, j++ )
         {
-            if( i >= sizeof( s ) - 1 )
-                break;
+            if( j >= sizeof( s ) - 1 )
+                return( MBEDTLS_ERR_X509_BUFFER_TOO_SMALL );
 
             c = name->val.p[i];
+            // Special characters requiring escaping, RFC 1779
+            if( c && strchr( ",=+<>#;\"\\", c ) )
+            {
+                if( j + 1 >= sizeof( s ) - 1 )
+                    return( MBEDTLS_ERR_X509_BUFFER_TOO_SMALL );
+                s[j++] = '\\';
+            }
             if( c < 32 || c >= 127 )
-                 s[i] = '?';
-            else s[i] = c;
+                 s[j] = '?';
+            else s[j] = c;
         }
-        s[i] = '\0';
+        s[j] = '\0';
         ret = mbedtls_snprintf( p, n, "%s", s );
         MBEDTLS_X509_SAFE_SNPRINTF;