uhashlib Module API Manual#
Overview#
The uhashlib module implements binary data hashing algorithms. The specific list of available algorithms depends on the board. Possible algorithms include:
SHA256- The current modern hash algorithm (SHA2 family). Suitable for cryptographically secure purposes. Included in the MicroPython core, and any board is recommended to provide this algorithm unless it has specific code size constraints.SHA1- A previous-generation algorithm. Not recommended for new uses, but SHA1 is part of some internet standards and existing applications, so boards targeting network connectivity and interoperability will try to provide this.MD5- A legacy algorithm not considered cryptographically secure. Only a few boards targeting interoperability with legacy applications will provide this.
Please refer to the MicroPython official hash documentation for details
Constructor#
sha256#
Description
Creates a SHA256 hash object, and optionally feeds data into it.
Syntax
obj = uhashlib.sha256([data])
Parameters
Parameter |
Description |
Input/Output |
|---|---|---|
data (optional) |
Binary data |
Input |
Return Value
Returns the SHA256 hash object.
sha1#
Description
Creates a SHA1 hash object, and optionally feeds data into it.
Syntax
obj = uhashlib.sha1([data])
Parameters
Parameter |
Description |
Input/Output |
|---|---|---|
data (optional) |
Binary data |
Input |
Return Value
Returns the SHA1 hash object.
md5#
Description
Creates an MD5 hash object, and optionally feeds data into it.
Syntax
obj = uhashlib.md5([data])
Parameters
Parameter |
Description |
Input/Output |
|---|---|---|
data (optional) |
Binary data |
Input |
Return Value
Returns the MD5 hash object.
Hasher Object Methods#
Data Update Function update()#
Description
Inputs more binary data into the hash.
Syntax
hash.update(data)
Parameters
Parameter |
Description |
Input/Output |
|---|---|---|
data |
Binary data |
Input |
Return Value
None
Message Digest Function digest()#
Description
Returns the hash value of all data passed through the hash as a bytes object.
Note: After calling this method, no more data can be input into the hash.
Syntax
dgst = hash.digest()
Parameters
None
Return Value
Returns the hash value of all data passed through the hash.
Hexadecimal Message Digest Function hexdigest()#
This method is not implemented. You can use binascii.hexlify(hash.digest()) to achieve a similar effect.
Example Program#
import uhashlib
print('###################### SHA256 Test ##############################')
print('********************** Test-1: Only Call update() Once ******************')
# 初始化sha256对象
obj = uhashlib.sha256()
# 输入消息message
msg = b'\x45\x11\x01\x25\x0e\xc6\xf2\x66\x52\x24\x9d\x59\xdc\x97\x4b\x73\x61\xd5\x71\xa8\x10\x1c\xdf\xd3\x6a\xba\x3b\x58\x54\xd3\xae\x08\x6b\x5f\xdd\x45\x97\x72\x1b\x66\xe3\xc0\xdc\x5d\x8c\x60\x6d\x96\x57\xd0\xe3\x23\x28\x3a\x52\x17\xd1\xf5\x3f\x2f\x28\x4f\x57\xb8'
# 标准哈希值
dgst0 = b'\x1a\xaa\xf9\x28\x5a\xf9\x45\xb8\xa9\x7c\xf1\x4f\x86\x9b\x18\x90\x14\xc3\x84\xf3\xc7\xc2\xb7\xd2\xdf\x8a\x97\x13\xbf\xfe\x0b\xf1'
# 将消息更新到硬件IP中
obj.update(msg)
# 计算哈希值
dgst = obj.digest()
print(dgst0 == dgst)
# print(binascii.hexlify(dgst))
print('********************** Test-2: Call update() Twice ******************')
dgst0 = b'\x93\x6a\x18\x5c\xaa\xa2\x66\xbb\x9c\xbe\x98\x1e\x9e\x05\xcb\x78\xcd\x73\x2b\x0b\x32\x80\xeb\x94\x44\x12\xbb\x6f\x8f\x8f\x07\xaf'
obj = uhashlib.sha256()
# 向硬件多次更新消息
obj.update(b'hello')
obj.update(b'world')
dgst = obj.digest()
print(dgst0 == dgst)
# print('********************** Test-3: Call digest() Twice ******************')
# dgst0 = b'\x93\x6a\x18\x5c\xaa\xa2\x66\xbb\x9c\xbe\x98\x1e\x9e\x05\xcb\x78\xcd\x73\x2b\x0b\x32\x80\xeb\x94\x44\x12\xbb\x6f\x8f\x8f\x07\xaf'
# obj = uhashlib.sha256()
# obj.update(b'hello')
# obj.update(b'world')
# dgst = obj.digest()
# dgst1 = obj.digest() # 错误，digest() 只能调用一次
# print(dgst0 == dgst)
# print(dgst == dgst1)