1
0
Fork 0
mirror of https://github.com/borgbackup/borg.git synced 2024-12-24 08:45:13 +00:00

crypto.pyx: cosmetic changes, added comments

This commit is contained in:
Thomas Waldmann 2015-03-03 20:11:28 +01:00
parent 6c7c2e2e40
commit 550320535c

View file

@ -8,7 +8,7 @@ from libc.stdlib cimport malloc, free
API_VERSION = 2
cdef extern from "openssl/rand.h":
int RAND_bytes(unsigned char *buf,int num)
int RAND_bytes(unsigned char *buf, int num)
cdef extern from "openssl/evp.h":
@ -26,18 +26,16 @@ cdef extern from "openssl/evp.h":
void EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *a)
void EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *a)
int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx,const EVP_CIPHER *cipher, ENGINE *impl,
int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl,
const unsigned char *key, const unsigned char *iv)
int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx,const EVP_CIPHER *cipher, ENGINE *impl,
int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl,
const unsigned char *key, const unsigned char *iv)
int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out,
int *outl, const unsigned char *in_, int inl)
int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out,
int *outl, const unsigned char *in_, int inl)
int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out,
int *outl)
int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out,
int *outl)
int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
const unsigned char *in_, int inl)
int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
const unsigned char *in_, int inl)
int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
int PKCS5_PBKDF2_HMAC(const char *password, int passwordlen,
const unsigned char *salt, int saltlen, int iter,
@ -55,7 +53,8 @@ long_to_bytes = lambda x: _long.pack(x)
def num_aes_blocks(length):
"""Return the number of AES blocks required to encrypt/decrypt *length* bytes of data
"""Return the number of AES blocks required to encrypt/decrypt *length* bytes of data.
Note: this is only correct for modes without padding, like AES-CTR.
"""
return (length + 15) // 16
@ -160,7 +159,10 @@ cdef class AES:
if not EVP_DecryptUpdate(&self.ctx, out, &outl, data, inl):
raise Exception('EVP_DecryptUpdate failed')
ptl = outl
if EVP_DecryptFinal_ex(&self.ctx, out+outl, &outl) <= 0:
if EVP_DecryptFinal_ex(&self.ctx, out+ptl, &outl) <= 0:
# this error check is very important for modes with padding or
# authentication. for them, a failure here means corrupted data.
# CTR mode does not use padding nor authentication.
raise Exception('EVP_DecryptFinal failed')
ptl += outl
return out[:ptl]