3 [@sdZddlZddlZddlZddlZddlZddlZddlmZddl m Z ddl m Z m Z ddlmZddlmZejdZGd d d eZGd d d eZd dZddZddZd"ddZGdddZddedfddZddedfddZGdddZGd d!d!eZdS)#a_ Functions for creating and restoring url-safe signed JSON objects. The format used looks like this: >>> signing.dumps("hello") 'ImhlbGxvIg:1QaUZC:YIye-ze3TTx7gtSv422nZA4sgmk' There are two components here, separated by a ':'. The first component is a URLsafe base64 encoded JSON of the object passed to dumps(). The second component is a base64 encoded hmac/SHA1 hash of "$first_component:$secret" signing.loads(s) checks the signature and returns the deserialized object. If the signature fails, a BadSignature exception is raised. >>> signing.loads("ImhlbGxvIg:1QaUZC:YIye-ze3TTx7gtSv422nZA4sgmk") 'hello' >>> signing.loads("ImhlbGxvIg:1QaUZC:YIye-ze3TTx7gtSv422nZA4sgmk-modified") ... BadSignature: Signature failed: ImhlbGxvIg:1QaUZC:YIye-ze3TTx7gtSv422nZA4sgmk-modified You can optionally compress the JSON prior to base64 encoding it to save space, using the compress=True argument. This checks if compression actually helps and only applies compression if the result is a shorter string: >>> signing.dumps(range(1, 20), compress=True) '.eJwFwcERACAIwLCF-rCiILN47r-GyZVJsNgkxaFxoDgxcOHGxMKD_T7vhAml:1QaUaL:BA0thEZrp4FQVXIXuOvYJtLJSrQ' The fact that the string is compressed is signalled by the prefixed '.' at the start of the base64 JSON. There are 65 url-safe characters: the 64 used by url-safe base64 and the ':'. These functions make use of all of them. N)settings)baseconv)constant_time_compare salted_hmac) force_bytes) import_stringz^[A-z0-9-_=]*$c@seZdZdZdS) BadSignaturezSignature does not match.N)__name__ __module__ __qualname____doc__r r 7/tmp/pip-install-j7i95hgp/django/django/core/signing.pyr4src@seZdZdZdS)SignatureExpiredz3Signature timestamp is older than required max_age.N)r r r r r r r rr9srcCstj|jdS)N=)base64urlsafe_b64encodestrip)sr r r b64_encode>srcCs dt| d}tj||S)Nr)lenrurlsafe_b64decode)rpadr r r b64_decodeBsrcCstt|||jjS)N)rrdigestdecode)saltvaluekeyr r r base64_hmacGsr %django.core.signing.get_cookie_signercCs$ttj}ttj}|d||dS)Nsdjango.http.cookies)r)rrZSIGNING_BACKENDr SECRET_KEY)rSignerrr r rget_cookie_signerKs  r$c@s eZdZdZddZddZdS)JSONSerializerzW Simple wrapper around json to be used in signing.dumps and signing.loads. cCstj|ddjdS)N,:) separatorszlatin-1)r&r')jsondumpsencode)selfobjr r rr*VszJSONSerializer.dumpscCstj|jdS)Nzlatin-1)r)loadsr)r,datar r rr.YszJSONSerializer.loadsN)r r r r r*r.r r r rr%Qsr%zdjango.core.signingFc Csd|j|}d}|r:tj|}t|t|dkr:|}d}t|j}|rRd|}t||dj|S)a Return URL-safe, hmac/SHA1 signed base64 compressed JSON string. If key is None, use settings.SECRET_KEY instead. If compress is True (not the default), check if compressing using zlib can save some space. Prepend a '.' to signify compression. This is included in the signature, to protect against zip bombs. Salt can be used to namespace the hash, so that a signed string is only valid for a given namespace. Leaving this at the default value or re-using a salt value across different parts of your application without good cause is a security risk. The serializer is expected to return a bytestring. FT.)r)r*zlibcompressrrrTimestampSignersign) r-rr serializerr3r/Z is_compressed compressedbase64dr r rr*]s   r*cCs\t||dj||dj}|dddk}|r:|dd}t|}|rPtj|}|j|S)z| Reverse of dumps(), raise BadSignature if signature fails. The serializer is expected to accept a bytestring. )r)max_ageNr0.)r4unsignr+rr2 decompressr.)rrrr6r9r8r<r/r r rr.~s  r.c@s.eZdZd ddZddZddZd d ZdS) r#Nr'cCsH|ptj|_||_tj|jr*td||p@d|jj|jj f|_ dS)NzJUnsafe Signer separator: %r (cannot be empty or consist of only A-z0-9-_=)z%s.%s) rr"rsep _SEP_UNSAFEmatch ValueError __class__r r r)r,rr=rr r r__init__s  zSigner.__init__cCst|jd||jS)NZsigner)r rr)r,rr r r signatureszSigner.signaturecCsd||j|j|fS)Nz%s%s%s)r=rC)r,rr r rr5sz Signer.signcCsN|j|krtd|j|j|jd\}}t||j|r>|Std|dS)NzNo "%s" found in valuer0zSignature "%s" does not match)r=rrsplitrrC)r,Z signed_valuersigr r rr;s  z Signer.unsign)Nr'N)r r r rBrCr5r;r r r rr#s r#cs2eZdZddZfddZdfdd ZZS) r4cCstjjttjS)N)rbase62r+inttime)r,r r r timestampszTimestampSigner.timestampcs d||j|jf}tj|S)Nz%s%s%s)r=rIsuperr5)r,r)rAr rr5szTimestampSigner.signNcsntj|}|j|jd\}}tjj|}|dk rjt|tj rF|j }t j |}||krjt d||f|S)zk Retrieve original value and check it wasn't signed more than max_age seconds ago. r0NzSignature age %s > %s seconds) rJr;rDr=rrFr isinstancedatetime timedelta total_secondsrHr)r,rr9resultrIZage)rAr rr;s    zTimestampSigner.unsign)N)r r r rIr5r; __classcell__r r )rArr4s r4)r!) r rrLr)rerHr2Z django.confrZ django.utilsrZdjango.utils.cryptorrZdjango.utils.encodingrZdjango.utils.module_loadingrcompiler> Exceptionrrrrr r$r%r*r.r#r4r r r r"s.       !