xref: /freebsd/crypto/openssl/doc/man3/ERR_put_error.pod (revision b077aed33b7b6aefca7b17ddb250cf521f938613)
1=pod
2
3=for openssl foreign manual errno(3)
4
5=head1 NAME
6
7ERR_raise, ERR_raise_data,
8ERR_put_error, ERR_add_error_data, ERR_add_error_vdata,
9ERR_add_error_txt, ERR_add_error_mem_bio
10- record an error
11
12=head1 SYNOPSIS
13
14 #include <openssl/err.h>
15
16 void ERR_raise(int lib, int reason);
17 void ERR_raise_data(int lib, int reason, const char *fmt, ...);
18
19 void ERR_add_error_data(int num, ...);
20 void ERR_add_error_vdata(int num, va_list arg);
21 void ERR_add_error_txt(const char *sep, const char *txt);
22 void ERR_add_error_mem_bio(const char *sep, BIO *bio);
23
24The following function has been deprecated since OpenSSL 3.0, and can be
25hidden entirely by defining B<OPENSSL_API_COMPAT> with a suitable version value,
26see L<openssl_user_macros(7)>:
27
28 void ERR_put_error(int lib, int func, int reason, const char *file, int line);
29
30=head1 DESCRIPTION
31
32ERR_raise() adds a new error to the thread's error queue.  The
33error occurred in the library B<lib> for the reason given by the
34B<reason> code.  Furthermore, the name of the file, the line, and name
35of the function where the error occurred is saved with the error
36record.
37
38ERR_raise_data() does the same thing as ERR_raise(), but also lets the
39caller specify additional information as a format string B<fmt> and an
40arbitrary number of values, which are processed with L<BIO_snprintf(3)>.
41
42ERR_put_error() adds an error code to the thread's error queue. It
43signals that the error of reason code B<reason> occurred in function
44B<func> of library B<lib>, in line number B<line> of B<file>.
45This function is usually called by a macro.
46
47ERR_add_error_data() associates the concatenation of its B<num> string
48arguments as additional data with the error code added last.
49ERR_add_error_vdata() is similar except the argument is a B<va_list>.
50Multiple calls to these functions append to the current top of the error queue.
51The total length of the string data per error is limited to 4096 characters.
52
53ERR_add_error_txt() appends the given text string as additional data to the
54last error queue entry, after inserting the optional separator string if it is
55not NULL and the top error entry does not yet have additional data.
56In case the separator is at the end of the text it is not appended to the data.
57The B<sep> argument may be for instance "\n" to insert a line break when needed.
58If the associated data would become more than 4096 characters long
59(which is the limit given above)
60it is split over sufficiently many new copies of the last error queue entry.
61
62ERR_add_error_mem_bio() is the same as ERR_add_error_txt() except that
63the text string is taken from the given memory BIO.
64It appends '\0' to the BIO contents if not already NUL-terminated.
65
66L<ERR_load_strings(3)> can be used to register
67error strings so that the application can a generate human-readable
68error messages for the error code.
69
70=head2 Reporting errors
71
72=head3 OpenSSL library reports
73
74Each OpenSSL sub-library has library code B<ERR_LIB_XXX> and has its own set
75of reason codes B<XXX_R_...>.  These are both passed in combination to
76ERR_raise() and ERR_raise_data(), and the combination ultimately produces
77the correct error text for the reported error.
78
79All these macros and the numbers they have as values are specific to
80OpenSSL's libraries.  OpenSSL reason codes normally consist of textual error
81descriptions. For example, the function ssl3_read_bytes() reports a
82"handshake failure" as follows:
83
84 ERR_raise(ERR_LIB_SSL, SSL_R_SSL_HANDSHAKE_FAILURE);
85
86There are two exceptions:
87
88=over 4
89
90=item B<ERR_LIB_SYS>
91
92This "library code" indicates that a system error is being reported.  In
93this case, the reason code given to ERR_raise() and ERR_raise_data() I<must>
94be L<errno(3)>.
95
96 ERR_raise(ERR_LIB_SYS, errno);
97
98=item B<ERR_R_XXX>
99
100This set of error codes is considered global, and may be used in combination
101with any sub-library code.
102
103 ERR_raise(ERR_LIB_RSA, ERR_R_PASSED_INVALID_ARGUMENT);
104
105=back
106
107=head3 Other pieces of software
108
109Other pieces of software that may want to use OpenSSL's error reporting
110system, such as engines or applications, must normally get their own
111numbers.
112
113=over 4
114
115=item *
116
117To get a "library" code, call L<ERR_get_next_error_library(3)>; this gives
118the calling code a dynamic number, usable for the duration of the process.
119
120=item *
121
122Reason codes for each such "library" are determined or generated by the
123authors of that code.  They must be numbers in the range 1 to 524287 (in
124other words, they must be nonzero unsigned 18 bit integers).
125
126=back
127
128The exceptions mentioned in L</OpenSSL library reports> above are valid for
129other pieces of software, i.e. they may use B<ERR_LIB_SYS> to report system
130errors:
131
132 ERR_raise(ERR_LIB_SYS, errno);
133
134... and they may use B<ERR_R_XXX> macros together with their own "library"
135code.
136
137 int app_lib_code = ERR_get_next_error_library();
138
139 /* ... */
140
141 ERR_raise(app_lib_code, ERR_R_PASSED_INVALID_ARGUMENT);
142
143=begin comment
144
145[These are OpenSSL specific recommendations]
146
147Reason codes should consist of uppercase characters, numbers and underscores
148only. The error file generation script translates the trailing section of a
149reason code (after the "_R_") into lowercase with underscores changed to
150spaces.
151
152Although a library will normally report errors using its own specific
153B<ERR_LIB_XXX> macro, another library's macro can be used, together with
154that other library's reason codes. This is normally only done when a library
155wants to include ASN1 code which must be combined with B<ERR_LIB_ASN1>
156macro.
157
158=end comment
159
160=head1 RETURN VALUES
161
162ERR_raise(), ERR_raise_data(), ERR_put_error(),
163ERR_add_error_data(), ERR_add_error_vdata()
164ERR_add_error_txt(), and ERR_add_error_mem_bio()
165return no values.
166
167=head1 NOTES
168
169ERR_raise(), ERR_raise() and ERR_put_error() are implemented as macros.
170
171=head1 SEE ALSO
172
173L<ERR_load_strings(3)>, L<ERR_get_next_error_library(3)>
174
175=head1 HISTORY
176
177ERR_raise, ERR_raise_data, ERR_add_error_txt() and ERR_add_error_mem_bio()
178were added in OpenSSL 3.0.
179
180=head1 COPYRIGHT
181
182Copyright 2000-2021 The OpenSSL Project Authors. All Rights Reserved.
183
184Licensed under the Apache License 2.0 (the "License").  You may not use
185this file except in compliance with the License.  You can obtain a copy
186in the file LICENSE in the source distribution or at
187L<https://www.openssl.org/source/license.html>.
188
189=cut
190