Import OpenSSL 1.0.2k (as of svn r86089)

doc/crypto/X509_verify_cert.pod

@@ -0,0 +1,55 @@
+=pod
+
+=head1 NAME
+
+X509_verify_cert - discover and verify X509 certificte chain
+
+=head1 SYNOPSIS
+
+ #include <openssl/x509.h>
+
+ int X509_verify_cert(X509_STORE_CTX *ctx);
+
+=head1 DESCRIPTION
+
+The X509_verify_cert() function attempts to discover and validate a
+certificate chain based on parameters in B<ctx>. A complete description of
+the process is contained in the L<verify(1)|verify(1)> manual page.
+
+=head1 RETURN VALUES
+
+If a complete chain can be built and validated this function returns 1,
+otherwise it return zero, in exceptional circumstances it can also
+return a negative code.
+
+If the function fails additional error information can be obtained by
+examining B<ctx> using, for example X509_STORE_CTX_get_error().
+
+=head1 NOTES
+
+Applications rarely call this function directly but it is used by
+OpenSSL internally for certificate validation, in both the S/MIME and
+SSL/TLS code.
+
+A negative return value from X509_verify_cert() can occur if it is invoked
+incorrectly, such as with no certificate set in B<ctx>, or when it is called
+twice in succession without reinitialising B<ctx> for the second call.
+A negative return value can also happen due to internal resource problems or if
+a retry operation is requested during internal lookups (which never happens
+with standard lookup methods).
+Applications must check for <= 0 return value on error.
+
+=head1 BUGS
+
+This function uses the header B<x509.h> as opposed to most chain verification
+functiosn which use B<x509_vfy.h>.
+
+=head1 SEE ALSO
+
+L<X509_STORE_CTX_get_error(3)|X509_STORE_CTX_get_error(3)>
+
+=head1 HISTORY
+
+X509_verify_cert() is available in all versions of SSLeay and OpenSSL.
+
+=cut