1CMS_decrypt(3) OpenSSL CMS_decrypt(3)
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6 CMS_decrypt - decrypt content from a CMS envelopedData structure
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9 #include <openssl/cms.h>
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11 int CMS_decrypt(CMS_ContentInfo *cms, EVP_PKEY *pkey, X509 *cert, BIO *dcont, BIO *out, unsigned int flags);
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14 CMS_decrypt() extracts and decrypts the content from a CMS
15 EnvelopedData structure. pkey is the private key of the recipient, cert
16 is the recipient's certificate, out is a BIO to write the content to
17 and flags is an optional set of flags.
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19 The dcont parameter is used in the rare case where the encrypted
20 content is detached. It will normally be set to NULL.
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23 OpenSSL_add_all_algorithms() (or equivalent) should be called before
24 using this function or errors about unknown algorithms will occur.
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26 Although the recipients certificate is not needed to decrypt the data
27 it is needed to locate the appropriate (of possible several) recipients
28 in the CMS structure. If cert is set to NULL all possible recipients
29 are tried.
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31 It is possible to determine the correct recipient key by other means
32 (for example looking them up in a database) and setting them in the CMS
33 structure in advance using the CMS utility functions such as
34 CMS_set1_pkey(). In this case both cert and pkey should be set to NULL.
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36 To process KEKRecipientInfo types CMS_set1_key() or
37 CMS_RecipientInfo_set0_key() and CMS_ReceipientInfo_decrypt() should be
38 called before CMS_decrypt() and cert and pkey set to NULL.
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40 The following flags can be passed in the flags parameter.
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42 If the CMS_TEXT flag is set MIME headers for type text/plain are
43 deleted from the content. If the content is not of type text/plain then
44 an error is returned.
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47 CMS_decrypt() returns either 1 for success or 0 for failure. The error
48 can be obtained from ERR_get_error(3)
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51 The lack of single pass processing and the need to hold all data in
52 memory as mentioned in CMS_verify() also applies to CMS_decrypt().
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55 ERR_get_error(3), CMS_encrypt(3)
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58 CMS_decrypt() was added to OpenSSL 0.9.8
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621.0.0e 2008-04-11 CMS_decrypt(3)