Standard preamble:
========================================================================
..
.... 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 -- \(*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\} . 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.
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'.
.. .nr rF 0 . if \nF \{\ . de IX . tm Index:\\$1\t\\n%\t"\\$2" .. . if !\nF==2 \{\ . nr % 0 . nr F 2 . \} . \} .\} .rr rF Fear. Run. Save yourself. No user-serviceable parts.
. \" fudge factors for nroff and troff . ds #H 0 . ds #V .8m . ds #F .3m . ds #[ \f1 . ds #] .\} . ds #H ((1u-(\\\\n(.fu%2u))*.13m) . ds #V .6m . ds #F 0 . ds #[ \& . ds #] \& .\} . \" simple accents for nroff and troff . ds ' \& . ds ` \& . ds ^ \& . ds , \& . ds ~ ~ . ds / .\} . 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 . \" corrections for vroff . \" for low resolution devices (crt and lpr) \{\ . 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 .\} ========================================================================
Title "OSSL_PARAM_ALLOCATE_FROM_TEXT 3ossl"
way too many mistakes in technical documents.
OpenSSL 3.0 introduces a new mechanism to do the same thing with an array of parameters that contain name, value, value type and value size (see \s-1OSSL_PARAM\s0\|(3) for more information).
\fBOSSL_PARAM_allocate_from_text() uses key to look up an item in \fIparamdefs. If an item was found, it converts value to something suitable for that item's data_type, and stores the result in \fIto->data as well as its size in to->data_size. \fIto->key and to->data_type are assigned the corresponding values from the item that was found, and to->return_size is set to zero.
\fIto->data is always allocated using OPENSSL_zalloc\|(3) and needs to be freed by the caller when it's not useful any more, using \fBOPENSSL_free\|(3).
If found is not \s-1NULL,\s0 *found is set to 1 if key could be located in paramdefs, and to 0 otherwise.
When an item in paramdefs has been found, value is converted depending on that item's data_type, as follows:
0
All other attributes are ignored.
The data_size attribute can be zero, meaning that the parameter it describes expects arbitrary length data.
.Vb 4 int mac_ctrl_string(EVP_PKEY_CTX *ctx, const char *value) { int rv; char *stmp, *vtmp = NULL; \& stmp = OPENSSL_strdup(value); if (stmp == NULL) return -1; vtmp = strchr(stmp, \*(Aq:\*(Aq); if (vtmp != NULL) *vtmp++ = \*(Aq\e0\*(Aq; rv = EVP_MAC_ctrl_str(ctx, stmp, vtmp); OPENSSL_free(stmp); return rv; } \& ... \& \& for (i = 0; i < sk_OPENSSL_STRING_num(macopts); i++) { char *macopt = sk_OPENSSL_STRING_value(macopts, i); \& if (pkey_ctrl_string(mac_ctx, macopt) <= 0) { BIO_printf(bio_err, "MAC parameter error \e"%s\e"\en", macopt); ERR_print_errors(bio_err); goto mac_end; } } .Ve
Can be written like this instead:
.Vb 6 OSSL_PARAM *params = OPENSSL_zalloc(sizeof(*params) * (sk_OPENSSL_STRING_num(opts) + 1)); const OSSL_PARAM *paramdefs = EVP_MAC_settable_ctx_params(mac); size_t params_n; char *opt = "<unknown>"; \& for (params_n = 0; params_n < (size_t)sk_OPENSSL_STRING_num(opts); params_n++) { char *stmp, *vtmp = NULL; \& opt = sk_OPENSSL_STRING_value(opts, (int)params_n); if ((stmp = OPENSSL_strdup(opt)) == NULL || (vtmp = strchr(stmp, \*(Aq:\*(Aq)) == NULL) goto err; \& *vtmp++ = \*(Aq\e0\*(Aq; if (!OSSL_PARAM_allocate_from_text(¶ms[params_n], paramdefs, stmp, vtmp, strlen(vtmp), NULL)) goto err; } params[params_n] = OSSL_PARAM_construct_end(); if (!EVP_MAC_CTX_set_params(ctx, params)) goto err; while (params_n-- > 0) OPENSSL_free(params[params_n].data); OPENSSL_free(params); /* ... */ return; \& err: BIO_printf(bio_err, "MAC parameter error \*(Aq%s\*(Aq\en", opt); ERR_print_errors(bio_err); .Ve
Licensed under the Apache License 2.0 (the \*(L"License\*(R"). You may not use this file except in compliance with the License. You can obtain a copy in the file \s-1LICENSE\s0 in the source distribution or at <https://www.openssl.org/source/license.html>.