Edit File: SHA1_Init.3
.\" Automatically generated by Pod::Man 4.11 (Pod::Simple 3.35) .\" .\" Standard preamble: .\" ======================================================================== .de Sp \" Vertical space (when we can't use .PP) .if t .sp .5v .if n .sp .. .de Vb \" Begin verbatim text .ft CW .nf .ne \\$1 .. .de Ve \" End verbatim text .ft R .fi .. .\" Set up some character translations and predefined strings. \*(-- will .\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left .\" double quote, and \*(R" will give a right double quote. \*(C+ will .\" give a nicer C++. Capital omega is used to do unbreakable dashes and .\" therefore won't be available. \*(C` and \*(C' expand to `' in nroff, .\" nothing in troff, for use with C<>. .tr \(*W- .ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p' .ie n \{\ . ds -- \(*W- . ds PI pi . if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch . if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch . ds L" "" . ds R" "" . ds C` "" . ds C' "" 'br\} .el\{\ . ds -- \|\(em\| . ds PI \(*p . ds L" `` . ds R" '' . ds C` . ds C' 'br\} .\" .\" Escape single quotes in literal strings from groff's Unicode transform. .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" .\" If the F register is >0, we'll generate index entries on stderr for .\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index .\" entries marked with X<> in POD. Of course, you'll have to process the .\" output yourself in some meaningful fashion. .\" .\" Avoid warning from groff about undefined register 'F'. .de IX .. .nr rF 0 .if \n(.g .if rF .nr rF 1 .if (\n(rF:(\n(.g==0)) \{\ . if \nF \{\ . de IX . tm Index:\\$1\t\\n%\t"\\$2" .. . if !\nF==2 \{\ . nr % 0 . nr F 2 . \} . \} .\} .rr rF .\" .\" Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2). .\" Fear. Run. Save yourself. No user-serviceable parts. . \" fudge factors for nroff and troff .if n \{\ . ds #H 0 . ds #V .8m . ds #F .3m . ds #[ \f1 . ds #] \fP .\} .if t \{\ . ds #H ((1u-(\\\\n(.fu%2u))*.13m) . ds #V .6m . ds #F 0 . ds #[ \& . ds #] \& .\} . \" simple accents for nroff and troff .if n \{\ . ds ' \& . ds ` \& . ds ^ \& . ds , \& . ds ~ ~ . ds / .\} .if t \{\ . ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u" . ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u' . ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u' . ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u' . ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u' . ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u' .\} . \" troff and (daisy-wheel) nroff accents .ds : \\k:\h'-(\\n(.wu*8/10-\*(#H+.1m+\*(#F)'\v'-\*(#V'\z.\h'.2m+\*(#F'.\h'|\\n:u'\v'\*(#V' .ds 8 \h'\*(#H'\(*b\h'-\*(#H' .ds o \\k:\h'-(\\n(.wu+\w'\(de'u-\*(#H)/2u'\v'-.3n'\*(#[\z\(de\v'.3n'\h'|\\n:u'\*(#] .ds d- \h'\*(#H'\(pd\h'-\w'~'u'\v'-.25m'\f2\(hy\fP\v'.25m'\h'-\*(#H' .ds D- D\\k:\h'-\w'D'u'\v'-.11m'\z\(hy\v'.11m'\h'|\\n:u' .ds th \*(#[\v'.3m'\s+1I\s-1\v'-.3m'\h'-(\w'I'u*2/3)'\s-1o\s+1\*(#] .ds Th \*(#[\s+2I\s-2\h'-\w'I'u*3/5'\v'-.3m'o\v'.3m'\*(#] .ds ae a\h'-(\w'a'u*4/10)'e .ds Ae A\h'-(\w'A'u*4/10)'E . \" corrections for vroff .if v .ds ~ \\k:\h'-(\\n(.wu*9/10-\*(#H)'\s-2\u~\d\s+2\h'|\\n:u' .if v .ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'\v'-.4m'^\v'.4m'\h'|\\n:u' . \" for low resolution devices (crt and lpr) .if \n(.H>23 .if \n(.V>19 \ \{\ . ds : e . ds 8 ss . ds o a . ds d- d\h'-1'\(ga . ds D- D\h'-1'\(hy . ds th \o'bp' . ds Th \o'LP' . ds ae ae . ds Ae AE .\} .rm #[ #] #H #V #F C .\" ======================================================================== .\" .IX Title "sha 3" .TH sha 3 "2019-12-20" "1.0.2u" "OpenSSL" .\" For nroff, turn off justification. Always turn off hyphenation; it makes .\" way too many mistakes in technical documents. .if n .ad l .nh .SH "NAME" SHA1, SHA1_Init, SHA1_Update, SHA1_Final, SHA224, SHA224_Init, SHA224_Update, SHA224_Final, SHA256, SHA256_Init, SHA256_Update, SHA256_Final, SHA384, SHA384_Init, SHA384_Update, SHA384_Final, SHA512, SHA512_Init, SHA512_Update, SHA512_Final \- Secure Hash Algorithm .SH "SYNOPSIS" .IX Header "SYNOPSIS" .Vb 1 \& #include <openssl/sha.h> \& \& int SHA1_Init(SHA_CTX *c); \& int SHA1_Update(SHA_CTX *c, const void *data, size_t len); \& int SHA1_Final(unsigned char *md, SHA_CTX *c); \& unsigned char *SHA1(const unsigned char *d, size_t n, \& unsigned char *md); \& \& int SHA224_Init(SHA256_CTX *c); \& int SHA224_Update(SHA256_CTX *c, const void *data, size_t len); \& int SHA224_Final(unsigned char *md, SHA256_CTX *c); \& unsigned char *SHA224(const unsigned char *d, size_t n, \& unsigned char *md); \& \& int SHA256_Init(SHA256_CTX *c); \& int SHA256_Update(SHA256_CTX *c, const void *data, size_t len); \& int SHA256_Final(unsigned char *md, SHA256_CTX *c); \& unsigned char *SHA256(const unsigned char *d, size_t n, \& unsigned char *md); \& \& int SHA384_Init(SHA512_CTX *c); \& int SHA384_Update(SHA512_CTX *c, const void *data, size_t len); \& int SHA384_Final(unsigned char *md, SHA512_CTX *c); \& unsigned char *SHA384(const unsigned char *d, size_t n, \& unsigned char *md); \& \& int SHA512_Init(SHA512_CTX *c); \& int SHA512_Update(SHA512_CTX *c, const void *data, size_t len); \& int SHA512_Final(unsigned char *md, SHA512_CTX *c); \& unsigned char *SHA512(const unsigned char *d, size_t n, \& unsigned char *md); .Ve .SH "DESCRIPTION" .IX Header "DESCRIPTION" Applications should use the higher level functions \&\fBEVP_DigestInit\fR\|(3) etc. instead of calling the hash functions directly. .PP \&\s-1SHA\-1\s0 (Secure Hash Algorithm) is a cryptographic hash function with a 160 bit output. .PP \&\s-1\fBSHA1\s0()\fR computes the \s-1SHA\-1\s0 message digest of the \fBn\fR bytes at \fBd\fR and places it in \fBmd\fR (which must have space for \&\s-1SHA_DIGEST_LENGTH\s0 == 20 bytes of output). If \fBmd\fR is \s-1NULL,\s0 the digest is placed in a static array. Note: setting \fBmd\fR to \s-1NULL\s0 is \fBnot thread safe\fR. .PP The following functions may be used if the message is not completely stored in memory: .PP \&\fBSHA1_Init()\fR initializes a \fB\s-1SHA_CTX\s0\fR structure. .PP \&\fBSHA1_Update()\fR can be called repeatedly with chunks of the message to be hashed (\fBlen\fR bytes at \fBdata\fR). .PP \&\fBSHA1_Final()\fR places the message digest in \fBmd\fR, which must have space for \s-1SHA_DIGEST_LENGTH\s0 == 20 bytes of output, and erases the \fB\s-1SHA_CTX\s0\fR. .PP The \s-1SHA224, SHA256, SHA384\s0 and \s-1SHA512\s0 families of functions operate in the same way as for the \s-1SHA1\s0 functions. Note that \s-1SHA224\s0 and \s-1SHA256\s0 use a \&\fB\s-1SHA256_CTX\s0\fR object instead of \fB\s-1SHA_CTX\s0\fR. \s-1SHA384\s0 and \s-1SHA512\s0 use \fB\s-1SHA512_CTX\s0\fR. The buffer \fBmd\fR must have space for the output from the \s-1SHA\s0 variant being used (defined by \s-1SHA224_DIGEST_LENGTH, SHA256_DIGEST_LENGTH, SHA384_DIGEST_LENGTH\s0 and \&\s-1SHA512_DIGEST_LENGTH\s0). Also note that, as for the \s-1\fBSHA1\s0()\fR function above, the \&\s-1\fBSHA224\s0()\fR, \s-1\fBSHA256\s0()\fR, \s-1\fBSHA384\s0()\fR and \s-1\fBSHA512\s0()\fR functions are not thread safe if \&\fBmd\fR is \s-1NULL.\s0 .PP The predecessor of \s-1SHA\-1, SHA,\s0 is also implemented, but it should be used only when backward compatibility is required. .SH "RETURN VALUES" .IX Header "RETURN VALUES" \&\s-1\fBSHA1\s0()\fR, \s-1\fBSHA224\s0()\fR, \s-1\fBSHA256\s0()\fR, \s-1\fBSHA384\s0()\fR and \s-1\fBSHA512\s0()\fR return a pointer to the hash value. .PP \&\fBSHA1_Init()\fR, \fBSHA1_Update()\fR and \fBSHA1_Final()\fR and equivalent \s-1SHA224, SHA256, SHA384\s0 and \s-1SHA512\s0 functions return 1 for success, 0 otherwise. .SH "CONFORMING TO" .IX Header "CONFORMING TO" \&\s-1US\s0 Federal Information Processing Standard \s-1FIPS PUB 180\-4\s0 (Secure Hash Standard), \&\s-1ANSI X9.30\s0 .SH "SEE ALSO" .IX Header "SEE ALSO" \&\fBripemd\fR\|(3), \fBhmac\fR\|(3), \fBEVP_DigestInit\fR\|(3) .SH "HISTORY" .IX Header "HISTORY" \&\s-1\fBSHA1\s0()\fR, \fBSHA1_Init()\fR, \fBSHA1_Update()\fR and \fBSHA1_Final()\fR are available in all versions of SSLeay and OpenSSL.