Merge branch 'development'
diff --git a/ChangeLog b/ChangeLog
index fbc24cf..ebf4ab5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,6 @@
 mbed TLS ChangeLog (Sorted per branch, date)
 
-= mbed TLS x.x.x branch released xxxx-xx-xx
+= mbed TLS 2.x.x branch released xxxx-xx-xx
 
 Bugfix
    * Fix the redefinition of macro ssl_set_bio to an undefined symbol
@@ -14,6 +14,17 @@
      in RFC 6347 Section 4.3.1. This could cause the execution of the
      renegotiation routines at unexpected times when the protocol is DTLS. Found
      by wariua. #687
+   * Fixed potential arithmetic overflow in mbedtls_ctr_drbg_reseed() that could
+     cause buffer bound checks to be bypassed. Found by Eyal Itkin.
+   * Fixed potential arithmetic overflows in mbedtls_cipher_update() that could
+     cause buffer bound checks to be bypassed. Found by Eyal Itkin.
+   * Fixed potential arithmetic overflow in mbedtls_md2_update() that could
+     cause buffer bound checks to be bypassed. Found by Eyal Itkin.
+   * Fixed potential arithmetic overflow in mbedtls_base64_decode() that could
+     cause buffer bound checks to be bypassed. Found by Eyal Itkin.
+   * Fixed multiple buffer overreads in mbedtls_pem_read_buffer() when parsing
+     the input string in PEM format to extract the different components. Found
+     by Eyal Itkin.
 
 = mbed TLS 2.4.1 branch released 2016-12-13
 
diff --git a/library/base64.c b/library/base64.c
index 5cb12cb..f06b57b 100644
--- a/library/base64.c
+++ b/library/base64.c
@@ -192,7 +192,11 @@
         return( 0 );
     }
 
-    n = ( ( n * 6 ) + 7 ) >> 3;
+    /* The following expression is to calculate the following formula without
+     * risk of integer overflow in n:
+     *     n = ( ( n * 6 ) + 7 ) >> 3;
+     */
+    n = ( 6 * ( n >> 3 ) ) + ( ( 6 * ( n & 0x7 ) + 7 ) >> 3 );
     n -= j;
 
     if( dst == NULL || dlen < n )
diff --git a/library/cipher.c b/library/cipher.c
index a883438..e9e0b22 100644
--- a/library/cipher.c
+++ b/library/cipher.c
@@ -326,9 +326,9 @@
          * If there is not enough data for a full block, cache it.
          */
         if( ( ctx->operation == MBEDTLS_DECRYPT &&
-                ilen + ctx->unprocessed_len <= block_size ) ||
+                ilen <= block_size - ctx->unprocessed_len ) ||
              ( ctx->operation == MBEDTLS_ENCRYPT &&
-                ilen + ctx->unprocessed_len < block_size ) )
+                ilen < block_size - ctx->unprocessed_len ) )
         {
             memcpy( &( ctx->unprocessed_data[ctx->unprocessed_len] ), input,
                     ilen );
diff --git a/library/ctr_drbg.c b/library/ctr_drbg.c
index 386f8ad..55612c7 100644
--- a/library/ctr_drbg.c
+++ b/library/ctr_drbg.c
@@ -290,7 +290,8 @@
     unsigned char seed[MBEDTLS_CTR_DRBG_MAX_SEED_INPUT];
     size_t seedlen = 0;
 
-    if( ctx->entropy_len + len > MBEDTLS_CTR_DRBG_MAX_SEED_INPUT )
+    if( ctx->entropy_len > MBEDTLS_CTR_DRBG_MAX_SEED_INPUT ||
+        len > MBEDTLS_CTR_DRBG_MAX_SEED_INPUT - ctx->entropy_len )
         return( MBEDTLS_ERR_CTR_DRBG_INPUT_TOO_BIG );
 
     memset( seed, 0, MBEDTLS_CTR_DRBG_MAX_SEED_INPUT );
diff --git a/library/md2.c b/library/md2.c
index 8976701..95cbcce 100644
--- a/library/md2.c
+++ b/library/md2.c
@@ -158,7 +158,7 @@
 
     while( ilen > 0 )
     {
-        if( ctx->left + ilen > 16 )
+        if( ilen > 16 - ctx->left )
             fill = 16 - ctx->left;
         else
             fill = ilen;
diff --git a/library/pem.c b/library/pem.c
index b6ad53b..8dd86a4 100644
--- a/library/pem.c
+++ b/library/pem.c
@@ -249,7 +249,7 @@
 
     enc = 0;
 
-    if( memcmp( s1, "Proc-Type: 4,ENCRYPTED", 22 ) == 0 )
+    if( s2 - s1 >= 22 && memcmp( s1, "Proc-Type: 4,ENCRYPTED", 22 ) == 0 )
     {
 #if defined(MBEDTLS_MD5_C) && defined(MBEDTLS_CIPHER_MODE_CBC) &&         \
     ( defined(MBEDTLS_DES_C) || defined(MBEDTLS_AES_C) )
@@ -262,22 +262,22 @@
 
 
 #if defined(MBEDTLS_DES_C)
-        if( memcmp( s1, "DEK-Info: DES-EDE3-CBC,", 23 ) == 0 )
+        if( s2 - s1 >= 23 && memcmp( s1, "DEK-Info: DES-EDE3-CBC,", 23 ) == 0 )
         {
             enc_alg = MBEDTLS_CIPHER_DES_EDE3_CBC;
 
             s1 += 23;
-            if( pem_get_iv( s1, pem_iv, 8 ) != 0 )
+            if( s2 - s1 < 16 || pem_get_iv( s1, pem_iv, 8 ) != 0 )
                 return( MBEDTLS_ERR_PEM_INVALID_ENC_IV );
 
             s1 += 16;
         }
-        else if( memcmp( s1, "DEK-Info: DES-CBC,", 18 ) == 0 )
+        else if( s2 - s1 >= 18 && memcmp( s1, "DEK-Info: DES-CBC,", 18 ) == 0 )
         {
             enc_alg = MBEDTLS_CIPHER_DES_CBC;
 
             s1 += 18;
-            if( pem_get_iv( s1, pem_iv, 8) != 0 )
+            if( s2 - s1 < 16 || pem_get_iv( s1, pem_iv, 8) != 0 )
                 return( MBEDTLS_ERR_PEM_INVALID_ENC_IV );
 
             s1 += 16;
@@ -285,9 +285,11 @@
 #endif /* MBEDTLS_DES_C */
 
 #if defined(MBEDTLS_AES_C)
-        if( memcmp( s1, "DEK-Info: AES-", 14 ) == 0 )
+        if( s2 - s1 >= 14 && memcmp( s1, "DEK-Info: AES-", 14 ) == 0 )
         {
-            if( memcmp( s1, "DEK-Info: AES-128-CBC,", 22 ) == 0 )
+            if( s2 - s1 < 22 )
+                return( MBEDTLS_ERR_PEM_UNKNOWN_ENC_ALG );
+            else if( memcmp( s1, "DEK-Info: AES-128-CBC,", 22 ) == 0 )
                 enc_alg = MBEDTLS_CIPHER_AES_128_CBC;
             else if( memcmp( s1, "DEK-Info: AES-192-CBC,", 22 ) == 0 )
                 enc_alg = MBEDTLS_CIPHER_AES_192_CBC;
@@ -297,7 +299,7 @@
                 return( MBEDTLS_ERR_PEM_UNKNOWN_ENC_ALG );
 
             s1 += 22;
-            if( pem_get_iv( s1, pem_iv, 16 ) != 0 )
+            if( s2 - s1 < 32 || pem_get_iv( s1, pem_iv, 16 ) != 0 )
                 return( MBEDTLS_ERR_PEM_INVALID_ENC_IV );
 
             s1 += 32;
@@ -316,7 +318,7 @@
           ( MBEDTLS_AES_C || MBEDTLS_DES_C ) */
     }
 
-    if( s1 == s2 )
+    if( s1 >= s2 )
         return( MBEDTLS_ERR_PEM_INVALID_DATA );
 
     ret = mbedtls_base64_decode( NULL, 0, &len, s1, s2 - s1 );
diff --git a/tests/suites/test_suite_ctr_drbg.function b/tests/suites/test_suite_ctr_drbg.function
index 3acfb8b..883cfe0 100644
--- a/tests/suites/test_suite_ctr_drbg.function
+++ b/tests/suites/test_suite_ctr_drbg.function
@@ -39,6 +39,11 @@
     TEST_ASSERT( mbedtls_ctr_drbg_reseed( &ctx, additional,
                         MBEDTLS_CTR_DRBG_MAX_SEED_INPUT + 1 ) ==
                         MBEDTLS_ERR_CTR_DRBG_INPUT_TOO_BIG );
+
+    mbedtls_ctr_drbg_set_entropy_len( &ctx, ~0 );
+    TEST_ASSERT( mbedtls_ctr_drbg_reseed( &ctx, additional,
+                        MBEDTLS_CTR_DRBG_MAX_SEED_INPUT ) ==
+                        MBEDTLS_ERR_CTR_DRBG_INPUT_TOO_BIG );
 exit:
     mbedtls_ctr_drbg_free( &ctx );
 }
diff --git a/tests/suites/test_suite_pem.data b/tests/suites/test_suite_pem.data
index 973c923..9a62db8 100644
--- a/tests/suites/test_suite_pem.data
+++ b/tests/suites/test_suite_pem.data
@@ -15,3 +15,12 @@
 
 PEM write (exactly two lines + 1)
 mbedtls_pem_write_buffer:"-----START TEST-----\n":"-----END TEST-----\n":"000102030405060708090A0B0C0D0E0F000102030405060708090A0B0C0D0E0F000102030405060708090A0B0C0D0E0F000102030405060708090A0B0C0D0E0F000102030405060708090A0B0C0D0E0F000102030405060708090A0B0C0D0E0F00":"-----START TEST-----\nAAECAwQFBgcICQoLDA0ODwABAgMEBQYHCAkKCwwNDg8AAQIDBAUGBwgJCgsMDQ4P\nAAECAwQFBgcICQoLDA0ODwABAgMEBQYHCAkKCwwNDg8AAQIDBAUGBwgJCgsMDQ4P\nAA==\n-----END TEST-----\n"
+
+PEM read (DES-EDE3-CBC + invalid iv)
+mbedtls_pem_read_buffer:"^":"$":"^\nProc-Type\: 4,ENCRYPTED\nDEK-Info\: DES-EDE3-CBC,00$":-4608
+
+PEM read (DES-CBC + invalid iv)
+mbedtls_pem_read_buffer:"^":"$":"^\nProc-Type\: 4,ENCRYPTED\nDEK-Info\: DES-CBC,00$":-4608
+
+PEM read (unknown encryption algorithm)
+mbedtls_pem_read_buffer:"^":"$":"^\nProc-Type\: 4,ENCRYPTED\nDEK-Info\: AES-,00$":-4736
diff --git a/tests/suites/test_suite_pem.function b/tests/suites/test_suite_pem.function
index 6a62bfe..5e02210 100644
--- a/tests/suites/test_suite_pem.function
+++ b/tests/suites/test_suite_pem.function
@@ -3,12 +3,7 @@
 #include "mbedtls/pem.h"
 /* END_HEADER */
 
-/* BEGIN_DEPENDENCIES
- * depends_on:MBEDTLS_PEM_WRITE_C
- * END_DEPENDENCIES
- */
-
-/* BEGIN_CASE */
+/* BEGIN_CASE depends_on:MBEDTLS_PEM_WRITE_C */
 void mbedtls_pem_write_buffer( char *start, char *end, char *buf_str, char *result_str )
 {
     unsigned char buf[5000];
@@ -38,3 +33,20 @@
     mbedtls_free( check_buf );
 }
 /* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_AES_C:MBEDTLS_DES_C:MBEDTLS_MD5_C:MBEDTLS_CIPHER_MODE_CBC */
+void mbedtls_pem_read_buffer( char *header, char *footer, char *data, int ret )
+{
+    mbedtls_pem_context ctx;
+    size_t use_len = 0;
+
+    mbedtls_pem_init( &ctx );
+
+    TEST_ASSERT( mbedtls_pem_read_buffer( &ctx, header, footer,
+                                          (const unsigned char *)data, NULL, 0,
+                                          &use_len ) == ret );
+
+exit:
+    mbedtls_pem_free( &ctx );
+}
+/* END_CASE */