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diff --git a/src/lib/libcrypto/doc/EVP_DigestInit.pod b/src/lib/libcrypto/doc/EVP_DigestInit.pod deleted file mode 100644 index 6d4e156ae3..0000000000 --- a/src/lib/libcrypto/doc/EVP_DigestInit.pod +++ /dev/null | |||
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1 | =pod | ||
2 | |||
3 | =head1 NAME | ||
4 | |||
5 | EVP_DigestInit, EVP_DigestUpdate, EVP_DigestFinal - EVP digest routines | ||
6 | |||
7 | =head1 SYNOPSIS | ||
8 | |||
9 | #include <openssl/evp.h> | ||
10 | |||
11 | void EVP_DigestInit(EVP_MD_CTX *ctx, const EVP_MD *type); | ||
12 | void EVP_DigestUpdate(EVP_MD_CTX *ctx, const void *d, unsigned int cnt); | ||
13 | void EVP_DigestFinal(EVP_MD_CTX *ctx, unsigned char *md, | ||
14 | unsigned int *s); | ||
15 | |||
16 | #define EVP_MAX_MD_SIZE (16+20) /* The SSLv3 md5+sha1 type */ | ||
17 | |||
18 | int EVP_MD_CTX_copy(EVP_MD_CTX *out,EVP_MD_CTX *in); | ||
19 | |||
20 | #define EVP_MD_type(e) ((e)->type) | ||
21 | #define EVP_MD_pkey_type(e) ((e)->pkey_type) | ||
22 | #define EVP_MD_size(e) ((e)->md_size) | ||
23 | #define EVP_MD_block_size(e) ((e)->block_size) | ||
24 | |||
25 | #define EVP_MD_CTX_md(e) (e)->digest) | ||
26 | #define EVP_MD_CTX_size(e) EVP_MD_size((e)->digest) | ||
27 | #define EVP_MD_CTX_block_size(e) EVP_MD_block_size((e)->digest) | ||
28 | #define EVP_MD_CTX_type(e) EVP_MD_type((e)->digest) | ||
29 | |||
30 | EVP_MD *EVP_md_null(void); | ||
31 | EVP_MD *EVP_md2(void); | ||
32 | EVP_MD *EVP_md5(void); | ||
33 | EVP_MD *EVP_sha(void); | ||
34 | EVP_MD *EVP_sha1(void); | ||
35 | EVP_MD *EVP_dss(void); | ||
36 | EVP_MD *EVP_dss1(void); | ||
37 | EVP_MD *EVP_mdc2(void); | ||
38 | EVP_MD *EVP_ripemd160(void); | ||
39 | |||
40 | const EVP_MD *EVP_get_digestbyname(const char *name); | ||
41 | #define EVP_get_digestbynid(a) EVP_get_digestbyname(OBJ_nid2sn(a)) | ||
42 | #define EVP_get_digestbyobj(a) EVP_get_digestbynid(OBJ_obj2nid(a)) | ||
43 | |||
44 | =head1 DESCRIPTION | ||
45 | |||
46 | The EVP digest routines are a high level interface to message digests. | ||
47 | |||
48 | EVP_DigestInit() initialises a digest context B<ctx> to use a digest | ||
49 | B<type>: this will typically be supplied by a function such as | ||
50 | EVP_sha1(). | ||
51 | |||
52 | EVP_DigestUpdate() hashes B<cnt> bytes of data at B<d> into the | ||
53 | digest context B<ctx>. This funtion can be called several times on the | ||
54 | same B<ctx> to hash additional data. | ||
55 | |||
56 | EVP_DigestFinal() retrieves the digest value from B<ctx> and places | ||
57 | it in B<md>. If the B<s> parameter is not NULL then the number of | ||
58 | bytes of data written (i.e. the length of the digest) will be written | ||
59 | to the integer at B<s>, at most B<EVP_MAX_MD_SIZE> bytes will be written. | ||
60 | After calling EVP_DigestFinal() no additional calls to EVP_DigestUpdate() | ||
61 | can be made, but EVP_DigestInit() can be called to initialiase a new | ||
62 | digest operation. | ||
63 | |||
64 | EVP_MD_CTX_copy() can be used to copy the message digest state from | ||
65 | B<in> to B<out>. This is useful if large amounts of data are to be | ||
66 | hashed which only differ in the last few bytes. | ||
67 | |||
68 | EVP_MD_size() and EVP_MD_CTX_size() return the size of the message digest | ||
69 | when passed an B<EVP_MD> or an B<EVP_MD_CTX> structure, i.e. the size of the | ||
70 | hash. | ||
71 | |||
72 | EVP_MD_block_size() and EVP_MD_CTX_block_size() return the block size of the | ||
73 | message digest when passed an B<EVP_MD> or an B<EVP_MD_CTX> structure. | ||
74 | |||
75 | EVP_MD_type() and EVP_MD_CTX_type() return the NID of the OBJECT IDENTIFIER | ||
76 | representing the given message digest when passed an B<EVP_MD> structure. | ||
77 | For example EVP_MD_type(EVP_sha1()) returns B<NID_sha1>. This function is | ||
78 | normally used when setting ASN1 OIDs. | ||
79 | |||
80 | EVP_MD_CTX_md() returns the B<EVP_MD> structure corresponding to the passed | ||
81 | B<EVP_MD_CTX>. | ||
82 | |||
83 | EVP_MD_pkey_type() returns the NID of the public key signing algorithm associated | ||
84 | with this digest. For example EVP_sha1() is associated with RSA so this will | ||
85 | return B<NID_sha1WithRSAEncryption>. This "link" between digests and signature | ||
86 | algorithms may not be retained in future versions of OpenSSL. | ||
87 | |||
88 | EVP_md2(), EVP_md5(), EVP_sha(), EVP_sha1(), EVP_mdc2() and EVP_ripemd160() | ||
89 | return B<EVP_MD> structures for the MD2, MD5, SHA, SHA1, MDC2 and RIPEMD160 digest | ||
90 | algorithms respectively. The associated signature algorithm is RSA in each case. | ||
91 | |||
92 | EVP_dss() and EVP_dss1() return B<EVP_MD> structures for SHA and SHA1 digest | ||
93 | algorithms but using DSS (DSA) for the signature algorithm. | ||
94 | |||
95 | EVP_md_null() is a "null" message digest that does nothing: i.e. the hash it | ||
96 | returns is of zero length. | ||
97 | |||
98 | EVP_get_digestbyname(), EVP_get_digestbynid() and EVP_get_digestbyobj() | ||
99 | return an B<EVP_MD> structure when passed a digest name, a digest NID or | ||
100 | an ASN1_OBJECT structure respectively. The digest table must be initialised | ||
101 | using, for example, OpenSSL_add_all_digests() for these functions to work. | ||
102 | |||
103 | =head1 RETURN VALUES | ||
104 | |||
105 | EVP_DigestInit(), EVP_DigestUpdate() and EVP_DigestFinal() do not return values. | ||
106 | |||
107 | EVP_MD_CTX_copy() returns 1 if successful or 0 for failure. | ||
108 | |||
109 | EVP_MD_type(), EVP_MD_pkey_type() and EVP_MD_type() return the NID of the | ||
110 | corresponding OBJECT IDENTIFIER or NID_undef if none exists. | ||
111 | |||
112 | EVP_MD_size(), EVP_MD_block_size(), EVP_MD_CTX_size(e), EVP_MD_size(), | ||
113 | EVP_MD_CTX_block_size() and EVP_MD_block_size() return the digest or block | ||
114 | size in bytes. | ||
115 | |||
116 | EVP_md_null(), EVP_md2(), EVP_md5(), EVP_sha(), EVP_sha1(), EVP_dss(), | ||
117 | EVP_dss1(), EVP_mdc2() and EVP_ripemd160() return pointers to the | ||
118 | corresponding EVP_MD structures. | ||
119 | |||
120 | EVP_get_digestbyname(), EVP_get_digestbynid() and EVP_get_digestbyobj() | ||
121 | return either an B<EVP_MD> structure or NULL if an error occurs. | ||
122 | |||
123 | =head1 NOTES | ||
124 | |||
125 | The B<EVP> interface to message digests should almost always be used in | ||
126 | preference to the low level interfaces. This is because the code then becomes | ||
127 | transparent to the digest used and much more flexible. | ||
128 | |||
129 | SHA1 is the digest of choice for new applications. The other digest algorithms | ||
130 | are still in common use. | ||
131 | |||
132 | =head1 EXAMPLE | ||
133 | |||
134 | This example digests the data "Test Message\n" and "Hello World\n", using the | ||
135 | digest name passed on the command line. | ||
136 | |||
137 | #include <stdio.h> | ||
138 | #include <openssl/evp.h> | ||
139 | |||
140 | main(int argc, char *argv[]) | ||
141 | { | ||
142 | EVP_MD_CTX mdctx; | ||
143 | const EVP_MD *md; | ||
144 | char mess1[] = "Test Message\n"; | ||
145 | char mess2[] = "Hello World\n"; | ||
146 | unsigned char md_value[EVP_MAX_MD_SIZE]; | ||
147 | int md_len, i; | ||
148 | |||
149 | OpenSSL_add_all_digests(); | ||
150 | |||
151 | if(!argv[1]) { | ||
152 | printf("Usage: mdtest digestname\n"); | ||
153 | exit(1); | ||
154 | } | ||
155 | |||
156 | md = EVP_get_digestbyname(argv[1]); | ||
157 | |||
158 | if(!md) { | ||
159 | printf("Unknown message digest %s\n", argv[1]); | ||
160 | exit(1); | ||
161 | } | ||
162 | |||
163 | EVP_DigestInit(&mdctx, md); | ||
164 | EVP_DigestUpdate(&mdctx, mess1, strlen(mess1)); | ||
165 | EVP_DigestUpdate(&mdctx, mess2, strlen(mess2)); | ||
166 | EVP_DigestFinal(&mdctx, md_value, &md_len); | ||
167 | |||
168 | printf("Digest is: "); | ||
169 | for(i = 0; i < md_len; i++) printf("%02x", md_value[i]); | ||
170 | printf("\n"); | ||
171 | } | ||
172 | |||
173 | =head1 BUGS | ||
174 | |||
175 | Several of the functions do not return values: maybe they should. Although the | ||
176 | internal digest operations will never fail some future hardware based operations | ||
177 | might. | ||
178 | |||
179 | The link between digests and signing algorithms results in a situation where | ||
180 | EVP_sha1() must be used with RSA and EVP_dss1() must be used with DSS | ||
181 | even though they are identical digests. | ||
182 | |||
183 | The size of an B<EVP_MD_CTX> structure is determined at compile time: this results | ||
184 | in code that must be recompiled if the size of B<EVP_MD_CTX> increases. | ||
185 | |||
186 | =head1 SEE ALSO | ||
187 | |||
188 | L<evp(3)|evp(3)>, L<HMAC(3)|HMAC(3)>, L<MD2(3)|MD2(3)>, | ||
189 | L<MD5(3)|MD5(3)>, L<MDC2(3)|MDC2(3)>, L<RIPEMD160(3)|RIPEMD160(3)>, | ||
190 | L<SHA1(3)|SHA1(3)> | ||
191 | |||
192 | =head1 HISTORY | ||
193 | |||
194 | EVP_DigestInit(), EVP_DigestUpdate() and EVP_DigestFinal() are | ||
195 | available in all versions of SSLeay and OpenSSL. | ||
196 | |||
197 | =cut | ||