From 729f404efec0795f7ed358e7b2fa08bd62cc1ae8 Mon Sep 17 00:00:00 2001 From: Nick Mathewson Date: Mon, 10 Jan 2011 12:07:34 -0500 Subject: Add logic in routerparse to not read overlong private keys I am not at all sure that it is possible to trigger a bug here, but better safe than sorry. --- src/common/crypto.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) (limited to 'src/common/crypto.c') diff --git a/src/common/crypto.c b/src/common/crypto.c index 3343980331..da4e03edd8 100644 --- a/src/common/crypto.c +++ b/src/common/crypto.c @@ -439,21 +439,23 @@ crypto_pk_generate_key(crypto_pk_env_t *env) return 0; } -/** Read a PEM-encoded private key from the string s into env. - * Return 0 on success, -1 on failure. +/** Read a PEM-encoded private key from the len-byte string s + * into env. Return 0 on success, -1 on failure. If len is -1, + * the string is nul-terminated. */ /* Used here, and used for testing. */ int crypto_pk_read_private_key_from_string(crypto_pk_env_t *env, - const char *s) + const char *s, ssize_t len) { BIO *b; tor_assert(env); tor_assert(s); + tor_assert(len < INT_MAX && len < SIZE_T_CEILING); - /* Create a read-only memory BIO, backed by the NUL-terminated string 's' */ - b = BIO_new_mem_buf((char*)s, -1); + /* Create a read-only memory BIO, backed by the string 's' */ + b = BIO_new_mem_buf((char*)s, (int)len); if (env->key) RSA_free(env->key); @@ -487,7 +489,7 @@ crypto_pk_read_private_key_from_filename(crypto_pk_env_t *env, } /* Try to parse it. */ - r = crypto_pk_read_private_key_from_string(env, contents); + r = crypto_pk_read_private_key_from_string(env, contents, -1); tor_free(contents); if (r) return -1; /* read_private_key_from_string already warned, so we don't.*/ -- cgit v1.2.3-54-g00ecf