diff options
Diffstat (limited to 'secure/lib/libcrypto/man/EVP_DigestVerifyInit.3')
| -rw-r--r-- | secure/lib/libcrypto/man/EVP_DigestVerifyInit.3 | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/secure/lib/libcrypto/man/EVP_DigestVerifyInit.3 b/secure/lib/libcrypto/man/EVP_DigestVerifyInit.3 new file mode 100644 index 0000000..4a7a522 --- /dev/null +++ b/secure/lib/libcrypto/man/EVP_DigestVerifyInit.3 @@ -0,0 +1,214 @@ +.\" Automatically generated by Pod::Man 2.28 (Pod::Simple 3.30) +.\" +.\" 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 turned on, 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 "EVP_DigestVerifyInit 3" +.TH EVP_DigestVerifyInit 3 "2016-03-01" "1.0.2g" "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" +EVP_DigestVerifyInit, EVP_DigestVerifyUpdate, EVP_DigestVerifyFinal \- EVP signature verification functions +.SH "SYNOPSIS" +.IX Header "SYNOPSIS" +.Vb 1 +\& #include <openssl/evp.h> +\& +\& int EVP_DigestVerifyInit(EVP_MD_CTX *ctx, EVP_PKEY_CTX **pctx, +\& const EVP_MD *type, ENGINE *e, EVP_PKEY *pkey); +\& int EVP_DigestVerifyUpdate(EVP_MD_CTX *ctx, const void *d, unsigned int cnt); +\& int EVP_DigestVerifyFinal(EVP_MD_CTX *ctx, const unsigned char *sig, size_t siglen); +.Ve +.SH "DESCRIPTION" +.IX Header "DESCRIPTION" +The \s-1EVP\s0 signature routines are a high level interface to digital signatures. +.PP +\&\fIEVP_DigestVerifyInit()\fR sets up verification context \fBctx\fR to use digest +\&\fBtype\fR from \s-1ENGINE \s0\fBimpl\fR and public key \fBpkey\fR. \fBctx\fR must be initialized +with \fIEVP_MD_CTX_init()\fR before calling this function. If \fBpctx\fR is not \s-1NULL\s0 the +\&\s-1EVP_PKEY_CTX\s0 of the verification operation will be written to \fB*pctx\fR: this +can be used to set alternative verification options. +.PP +\&\fIEVP_DigestVerifyUpdate()\fR hashes \fBcnt\fR bytes of data at \fBd\fR into the +verification context \fBctx\fR. This function can be called several times on the +same \fBctx\fR to include additional data. This function is currently implemented +using a macro. +.PP +\&\fIEVP_DigestVerifyFinal()\fR verifies the data in \fBctx\fR against the signature in +\&\fBsig\fR of length \fBsiglen\fR. +.SH "RETURN VALUES" +.IX Header "RETURN VALUES" +\&\fIEVP_DigestVerifyInit()\fR and \fIEVP_DigestVerifyUpdate()\fR return 1 for success and 0 +or a negative value for failure. In particular a return value of \-2 indicates +the operation is not supported by the public key algorithm. +.PP +\&\fIEVP_DigestVerifyFinal()\fR returns 1 for success; any other value indicates +failure. A return value of zero indicates that the signature did not verify +successfully (that is, tbs did not match the original data or the signature had +an invalid form), while other values indicate a more serious error (and +sometimes also indicate an invalid signature form). +.PP +The error codes can be obtained from \fIERR_get_error\fR\|(3). +.SH "NOTES" +.IX Header "NOTES" +The \fB\s-1EVP\s0\fR interface to digital signatures should almost always be used in +preference to the low level interfaces. This is because the code then becomes +transparent to the algorithm used and much more flexible. +.PP +In previous versions of OpenSSL there was a link between message digest types +and public key algorithms. This meant that \*(L"clone\*(R" digests such as \fIEVP_dss1()\fR +needed to be used to sign using \s-1SHA1\s0 and \s-1DSA.\s0 This is no longer necessary and +the use of clone digest is now discouraged. +.PP +For some key types and parameters the random number generator must be seeded +or the operation will fail. +.PP +The call to \fIEVP_DigestVerifyFinal()\fR internally finalizes a copy of the digest +context. This means that \fIEVP_VerifyUpdate()\fR and \fIEVP_VerifyFinal()\fR can +be called later to digest and verify additional data. +.PP +Since only a copy of the digest context is ever finalized the context must +be cleaned up after use by calling \fIEVP_MD_CTX_cleanup()\fR or a memory leak +will occur. +.SH "SEE ALSO" +.IX Header "SEE ALSO" +\&\fIEVP_DigestSignInit\fR\|(3), +\&\fIEVP_DigestInit\fR\|(3), \fIerr\fR\|(3), +\&\fIevp\fR\|(3), \fIhmac\fR\|(3), \fImd2\fR\|(3), +\&\fImd5\fR\|(3), \fImdc2\fR\|(3), \fIripemd\fR\|(3), +\&\fIsha\fR\|(3), \fIdgst\fR\|(1) +.SH "HISTORY" +.IX Header "HISTORY" +\&\fIEVP_DigestVerifyInit()\fR, \fIEVP_DigestVerifyUpdate()\fR and \fIEVP_DigestVerifyFinal()\fR +were first added to OpenSSL 1.0.0. |
