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diff --git a/doc/man/pam_conv.3 b/doc/man/pam_conv.3 deleted file mode 100644 index 34b61fb3..00000000 --- a/doc/man/pam_conv.3 +++ /dev/null @@ -1,129 +0,0 @@ -.\" Title: pam_conv -.\" Author: -.\" Generator: DocBook XSL Stylesheets v1.70.1 <http://docbook.sf.net/> -.\" Date: 06/27/2006 -.\" Manual: Linux\-PAM Manual -.\" Source: Linux\-PAM Manual -.\" -.TH "PAM_CONV" "3" "06/27/2006" "Linux\-PAM Manual" "Linux\-PAM Manual" -.\" disable hyphenation -.nh -.\" disable justification (adjust text to left margin only) -.ad l -.SH "NAME" -pam_conv \- PAM conversation function -.SH "SYNOPSIS" -.sp -.ft B -.nf -#include <security/pam_appl.h> -.fi -.ft -.sp -.RS 3n -.nf -struct pam_message { - int msg_style; - const char *msg; -}; - -struct pam_response { - char *resp; - int resp_retcode; -}; - -struct pam_conv { - int (*conv)(int num_msg, const struct pam_message **msg, - struct pam_response **resp, void *appdata_ptr); - void *appdata_ptr; -}; - -.fi -.RE -.SH "DESCRIPTION" -.PP -The PAM library uses an application\-defined callback to allow a direct communication between a loaded module and the application. This callback is specified by the -\fIstruct pam_conv\fR -passed to -\fBpam_start\fR(3) -at the start of the transaction. -.PP -When a module calls the referenced conv() function, the argument -\fIappdata_ptr\fR -is set to the second element of this structure. -.PP -The other arguments of a call to conv() concern the information exchanged by module and application. That is to say, -\fInum_msg\fR -holds the length of the array of pointers, -\fImsg\fR. After a successful return, the pointer -\fIresp\fR -points to an array of pam_response structures, holding the application supplied text. The -\fIresp_retcode\fR -member of this struct is unused and should be set to zero. It is the caller's responsibility to release both, this array and the responses themselves, using -\fBfree\fR(3). Note, -\fI*resp\fR -is a -\fIstruct pam_response\fR -array and not an array of pointers. -.PP -The number of responses is always equal to the -\fInum_msg\fR -conversation function argument. This does require that the response array is -\fBfree\fR(3)'d after every call to the conversation function. The index of the responses corresponds directly to the prompt index in the pam_message array. -.PP -On failure, the conversation function should release any resources it has allocated, and return one of the predefined PAM error codes. -.PP -Each message can have one of four types, specified by the -\fImsg_style\fR -member of -\fIstruct pam_message\fR: -.TP 3n -PAM_PROMPT_ECHO_OFF -Obtain a string without echoing any text. -.TP 3n -PAM_PROMPT_ECHO_ON -Obtain a string whilst echoing text. -.TP 3n -PAM_ERROR_MSG -Display an error message. -.TP 3n -PAM_TEXT_INFO -Display some text. -.PP -The point of having an array of messages is that it becomes possible to pass a number of things to the application in a single call from the module. It can also be convenient for the application that related things come at once: a windows based application can then present a single form with many messages/prompts on at once. -.PP -In passing, it is worth noting that there is a descrepency between the way Linux\-PAM handles the const struct pam_message **msg conversation function argument from the way that Solaris' PAM (and derivitives, known to include HP/UX, are there others?) does. Linux\-PAM interprets the msg argument as entirely equivalent to the following prototype const struct pam_message *msg[] (which, in spirit, is consistent with the commonly used prototypes for argv argument to the familiar main() function: char **argv; and char *argv[]). Said another way Linux\-PAM interprets the msg argument as a pointer to an array of num_meg read only 'struct pam_message' pointers. Solaris' PAM implementation interprets this argument as a pointer to a pointer to an array of num_meg pam_message structures. Fortunately, perhaps, for most module/application developers when num_msg has a value of one these two definitions are entirely equivalent. Unfortunately, casually raising this number to two has led to unanticipated compatibility problems. -.PP -For what its worth the two known module writer work\-arounds for trying to maintain source level compatibility with both PAM implementations are: -.TP 3n -\(bu -never call the conversation function with num_msg greater than one. -.TP 3n -\(bu -set up msg as doubly referenced so both types of conversation function can find the messages. That is, make -.sp -.RS 3n -.nf - msg[n] = & (( *msg )[n]) - -.fi -.RE -.SH "RETURN VALUES" -.TP 3n -PAM_BUF_ERR -Memory buffer error. -.TP 3n -PAM_CONV_ERR -Conversation failure. The application should not set -\fI*resp\fR. -.TP 3n -PAM_SUCCESS -Success. -.SH "SEE ALSO" -.PP - -\fBpam_start\fR(3), -\fBpam_set_item\fR(3), -\fBpam_get_item\fR(3), -\fBpam_strerror\fR(3), -\fBpam\fR(8) |