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diff --git a/src/lib/libcrypto/doc/EVP_SignInit.pod b/src/lib/libcrypto/doc/EVP_SignInit.pod deleted file mode 100644 index 6882211e02..0000000000 --- a/src/lib/libcrypto/doc/EVP_SignInit.pod +++ /dev/null | |||
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1 | =pod | ||
2 | |||
3 | =head1 NAME | ||
4 | |||
5 | EVP_SignInit, EVP_SignUpdate, EVP_SignFinal, EVP_PKEY_size | ||
6 | - EVP signing functions | ||
7 | |||
8 | =head1 SYNOPSIS | ||
9 | |||
10 | #include <openssl/evp.h> | ||
11 | |||
12 | int EVP_SignInit_ex(EVP_MD_CTX *ctx, const EVP_MD *type, ENGINE *impl); | ||
13 | int EVP_SignUpdate(EVP_MD_CTX *ctx, const void *d, unsigned int cnt); | ||
14 | int EVP_SignFinal(EVP_MD_CTX *ctx,unsigned char *sig,unsigned int *s, EVP_PKEY *pkey); | ||
15 | |||
16 | void EVP_SignInit(EVP_MD_CTX *ctx, const EVP_MD *type); | ||
17 | |||
18 | int EVP_PKEY_size(EVP_PKEY *pkey); | ||
19 | |||
20 | =head1 DESCRIPTION | ||
21 | |||
22 | The EVP signature routines are a high level interface to digital | ||
23 | signatures. | ||
24 | |||
25 | EVP_SignInit_ex() sets up signing context B<ctx> to use digest | ||
26 | B<type> from ENGINE B<impl>. B<ctx> must be initialized with | ||
27 | EVP_MD_CTX_init() before calling this function. | ||
28 | |||
29 | EVP_SignUpdate() hashes B<cnt> bytes of data at B<d> into the | ||
30 | signature context B<ctx>. This function can be called several times on the | ||
31 | same B<ctx> to include additional data. | ||
32 | |||
33 | EVP_SignFinal() signs the data in B<ctx> using the private key B<pkey> and | ||
34 | places the signature in B<sig>. B<sig> must be at least EVP_PKEY_size(pkey) | ||
35 | bytes in size. B<s> is an OUT parameter, and not used as an IN parameter. | ||
36 | The number of bytes of data written (i.e. the length of the signature) | ||
37 | will be written to the integer at B<s>, at most EVP_PKEY_size(pkey) bytes | ||
38 | will be written. | ||
39 | |||
40 | EVP_SignInit() initializes a signing context B<ctx> to use the default | ||
41 | implementation of digest B<type>. | ||
42 | |||
43 | EVP_PKEY_size() returns the maximum size of a signature in bytes. The actual | ||
44 | signature returned by EVP_SignFinal() may be smaller. | ||
45 | |||
46 | =head1 RETURN VALUES | ||
47 | |||
48 | EVP_SignInit_ex(), EVP_SignUpdate() and EVP_SignFinal() return 1 | ||
49 | for success and 0 for failure. | ||
50 | |||
51 | EVP_PKEY_size() returns the maximum size of a signature in bytes. | ||
52 | |||
53 | The error codes can be obtained by L<ERR_get_error(3)|ERR_get_error(3)>. | ||
54 | |||
55 | =head1 NOTES | ||
56 | |||
57 | The B<EVP> interface to digital signatures should almost always be used in | ||
58 | preference to the low level interfaces. This is because the code then becomes | ||
59 | transparent to the algorithm used and much more flexible. | ||
60 | |||
61 | Due to the link between message digests and public key algorithms the correct | ||
62 | digest algorithm must be used with the correct public key type. A list of | ||
63 | algorithms and associated public key algorithms appears in | ||
64 | L<EVP_DigestInit(3)|EVP_DigestInit(3)>. | ||
65 | |||
66 | The call to EVP_SignFinal() internally finalizes a copy of the digest context. | ||
67 | This means that calls to EVP_SignUpdate() and EVP_SignFinal() can be called | ||
68 | later to digest and sign additional data. | ||
69 | |||
70 | Since only a copy of the digest context is ever finalized the context must | ||
71 | be cleaned up after use by calling EVP_MD_CTX_cleanup() or a memory leak | ||
72 | will occur. | ||
73 | |||
74 | =head1 BUGS | ||
75 | |||
76 | Older versions of this documentation wrongly stated that calls to | ||
77 | EVP_SignUpdate() could not be made after calling EVP_SignFinal(). | ||
78 | |||
79 | Since the private key is passed in the call to EVP_SignFinal() any error | ||
80 | relating to the private key (for example an unsuitable key and digest | ||
81 | combination) will not be indicated until after potentially large amounts of | ||
82 | data have been passed through EVP_SignUpdate(). | ||
83 | |||
84 | It is not possible to change the signing parameters using these function. | ||
85 | |||
86 | The previous two bugs are fixed in the newer EVP_SignDigest*() function. | ||
87 | |||
88 | =head1 SEE ALSO | ||
89 | |||
90 | L<EVP_VerifyInit(3)|EVP_VerifyInit(3)>, | ||
91 | L<EVP_DigestInit(3)|EVP_DigestInit(3)>, L<err(3)|err(3)>, | ||
92 | L<evp(3)|evp(3)>, L<hmac(3)|hmac(3)>, L<md2(3)|md2(3)>, | ||
93 | L<md5(3)|md5(3)>, L<ripemd(3)|ripemd(3)>, | ||
94 | L<sha(3)|sha(3)>, L<dgst(1)|dgst(1)> | ||
95 | |||
96 | =head1 HISTORY | ||
97 | |||
98 | EVP_SignInit(), EVP_SignUpdate() and EVP_SignFinal() are | ||
99 | available in all versions of SSLeay and OpenSSL. | ||
100 | |||
101 | EVP_SignInit_ex() was added in OpenSSL 0.9.7. | ||
102 | |||
103 | =cut | ||