common/irs/irp.c

/*
 * Copyright (C) 2004-2006, 2008  Internet Systems Consortium, Inc. ("ISC")
 * Copyright (C) 1996, 1998-2001, 2003  Internet Software Consortium.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 */

#if !defined(LINT) && !defined(CODECENTER)
static const char rcsid[] = "$Id: irp.c,v 1.12 2008/11/14 02:36:51 marka Exp $";
#endif

/* Imports */

#include "port_before.h"

#include <syslog.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <stdarg.h>
#include <fcntl.h>
#include <syslog.h>
#include <ctype.h>
#include <unistd.h>

#include <isc/memcluster.h>

#include <irs.h>
#include <irp.h>

#include "irs_p.h"
#include "irp_p.h"

#include "port_after.h"

/* Forward. */

static void     irp_close(struct irs_acc *);

#define LINEINCR 128

#if !defined(SUN_LEN)
#define SUN_LEN(su) \
    (sizeof (*(su)) - sizeof ((su)->sun_path) + strlen((su)->sun_path))
#endif


/* Public */


/* send errors to syslog if true. */
int irp_log_errors = 1;

/*%
 * This module handles the irp module connection to irpd.
 *
 * The client expects a synchronous interface to functions like
 * getpwnam(3), so we can't use the ctl_* i/o library on this end of
 * the wire (it's used in the server).
 */

/*%
 * irs_acc *irs_irp_acc(const char *options);
 *
 *  Initialize the irp module.
 */
struct irs_acc *
irs_irp_acc(const char *options) {
    struct irs_acc *acc;
    struct irp_p *irp;

    UNUSED(options);

    if (!(acc = memget(sizeof *acc))) {
        errno = ENOMEM;
        return (NULL);
    }
    memset(acc, 0x5e, sizeof *acc);
    if (!(irp = memget(sizeof *irp))) {
        errno = ENOMEM;
        free(acc);
        return (NULL);
    }
    irp->inlast = 0;
    irp->incurr = 0;
    irp->fdCxn = -1;
    acc->private = irp;

#ifdef WANT_IRS_GR
    acc->gr_map = irs_irp_gr;
#else
    acc->gr_map = NULL;
#endif
#ifdef WANT_IRS_PW
    acc->pw_map = irs_irp_pw;
#else
    acc->pw_map = NULL;
#endif
    acc->sv_map = irs_irp_sv;
    acc->pr_map = irs_irp_pr;
    acc->ho_map = irs_irp_ho;
    acc->nw_map = irs_irp_nw;
    acc->ng_map = irs_irp_ng;
    acc->close = irp_close;
    return (acc);
}


int
irs_irp_connection_setup(struct irp_p *cxndata, int *warned) {
    if (irs_irp_is_connected(cxndata)) {
        return (0);
    } else if (irs_irp_connect(cxndata) != 0) {
        if (warned != NULL && !*warned) {
            syslog(LOG_ERR, "irpd connection failed: %m\n");
            (*warned)++;
        }

        return (-1);
    }

    return (0);
}

/*%
 * int irs_irp_connect(void);
 *
 *  Sets up the connection to the remote irpd server.
 *
 * Returns:
 *
 *  0 on success, -1 on failure.
 *
 */
int
irs_irp_connect(struct irp_p *pvt) {
    int flags;
    struct sockaddr *addr;
    struct sockaddr_in iaddr;
#ifndef NO_SOCKADDR_UN
    struct sockaddr_un uaddr;
#endif
    long ipaddr;
    const char *irphost;
    int code;
    char text[256];
    int socklen = 0;

    if (pvt->fdCxn != -1) {
        perror("fd != 1");
        return (-1);
    }

#ifndef NO_SOCKADDR_UN
    memset(&uaddr, 0, sizeof uaddr);
#endif
    memset(&iaddr, 0, sizeof iaddr);

    irphost = getenv(IRPD_HOST_ENV);
    if (irphost == NULL) {
        irphost = "127.0.0.1";
    }

#ifndef NO_SOCKADDR_UN
    if (irphost[0] == '/') {
        addr = (struct sockaddr *)&uaddr;
        strncpy(uaddr.sun_path, irphost, sizeof uaddr.sun_path);
        uaddr.sun_family = AF_UNIX;
        socklen = SUN_LEN(&uaddr);
#ifdef HAVE_SA_LEN
        uaddr.sun_len = socklen;
#endif
    } else
#endif
    {
        if (inet_pton(AF_INET, irphost, &ipaddr) != 1) {
            errno = EADDRNOTAVAIL;
            perror("inet_pton");
            return (-1);
        }

        addr = (struct sockaddr *)&iaddr;
        socklen = sizeof iaddr;
#ifdef HAVE_SA_LEN
        iaddr.sin_len = socklen;
#endif
        iaddr.sin_family = AF_INET;
        iaddr.sin_port = htons(IRPD_PORT);
        iaddr.sin_addr.s_addr = ipaddr;
    }


    pvt->fdCxn = socket(addr->sa_family, SOCK_STREAM, PF_UNSPEC);
    if (pvt->fdCxn < 0) {
        perror("socket");
        return (-1);
    }

    if (connect(pvt->fdCxn, addr, socklen) != 0) {
        perror("connect");
        return (-1);
    }

    flags = fcntl(pvt->fdCxn, F_GETFL, 0);
    if (flags < 0) {
        close(pvt->fdCxn);
        perror("close");
        return (-1);
    }

#if 0
    flags |= O_NONBLOCK;
    if (fcntl(pvt->fdCxn, F_SETFL, flags) < 0) {
        close(pvt->fdCxn);
        perror("fcntl");
        return (-1);
    }
#endif

    code = irs_irp_read_response(pvt, text, sizeof text);
    if (code != IRPD_WELCOME_CODE) {
        if (irp_log_errors) {
            syslog(LOG_WARNING, "Connection failed: %s", text);
        }
        irs_irp_disconnect(pvt);
        return (-1);
    }

    return (0);
}

/*%
 * int  irs_irp_is_connected(struct irp_p *pvt);
 *
 * Returns:
 *
 *  Non-zero if streams are setup to remote.
 *
 */

int
irs_irp_is_connected(struct irp_p *pvt) {
    return (pvt->fdCxn >= 0);
}

/*%
 * void
 * irs_irp_disconnect(struct irp_p *pvt);
 *
 *  Closes streams to remote.
 */

void
irs_irp_disconnect(struct irp_p *pvt) {
    if (pvt->fdCxn != -1) {
        close(pvt->fdCxn);
        pvt->fdCxn = -1;
    }
}


int
irs_irp_read_line(struct irp_p *pvt, char *buffer, int len) {
    char *realstart = &pvt->inbuffer[0];
    char *p, *start, *end;
    int spare;
    int i;
    int buffpos = 0;
    int left = len - 1;

    while (left > 0) {
        start = p = &pvt->inbuffer[pvt->incurr];
        end = &pvt->inbuffer[pvt->inlast];

        while (p != end && *p != '\n')
            p++;

        if (p == end) {
            /* Found no newline so shift data down if necessary
             * and append new data to buffer
             */
            if (start > realstart) {
                memmove(realstart, start, end - start);
                pvt->inlast = end - start;
                start = realstart;
                pvt->incurr = 0;
                end = &pvt->inbuffer[pvt->inlast];
            }

            spare = sizeof (pvt->inbuffer) - pvt->inlast;

            p = end;
            i = read(pvt->fdCxn, end, spare);
            if (i < 0) {
                close(pvt->fdCxn);
                pvt->fdCxn = -1;
                return (buffpos > 0 ? buffpos : -1);
            } else if (i == 0) {
                return (buffpos);
            }

            end += i;
            pvt->inlast += i;

            while (p != end && *p != '\n')
                p++;
        }

        if (p == end) {
            /* full buffer and still no newline */
            i = sizeof pvt->inbuffer;
        } else {
            /* include newline */
            i = p - start + 1;
        }

        if (i > left)
            i = left;
        memcpy(buffer + buffpos, start, i);
        pvt->incurr += i;
        buffpos += i;
        buffer[buffpos] = '\0';

        if (p != end) {
            left = 0;
        } else {
            left -= i;
        }
    }

#if 0
    fprintf(stderr, "read line: %s\n", buffer);
#endif
    return (buffpos);
}

/*%
 * int irp_read_response(struct irp_p *pvt);
 *
 * Returns:
 *
 *  The number found at the beginning of the line read from
 *  FP. 0 on failure(0 is not a legal response code). The
 *  rest of the line is discarded.
 *
 */

int
irs_irp_read_response(struct irp_p *pvt, char *text, size_t textlen) {
    char line[1024];
    int code;
    char *p;

    if (irs_irp_read_line(pvt, line, sizeof line) <= 0) {
        return (0);
    }

    p = strchr(line, '\n');
    if (p == NULL) {
        return (0);
    }

    if (sscanf(line, "%d", &code) != 1) {
        code = 0;
    } else if (text != NULL && textlen > 0U) {
        p = line;
        while (isspace((unsigned char)*p)) p++;
        while (isdigit((unsigned char)*p)) p++;
        while (isspace((unsigned char)*p)) p++;
        strncpy(text, p, textlen - 1);
        p[textlen - 1] = '\0';
    }

    return (code);
}

/*%
 * char *irp_read_body(struct irp_p *pvt, size_t *size);
 *
 *  Read in the body of a response. Terminated by a line with
 *  just a dot on it. Lines should be terminated with a CR-LF
 *  sequence, but we're nt piccky if the CR is missing.
 *  No leading dot escaping is done as the protcol doesn't
 *  use leading dots anywhere.
 *
 * Returns:
 *
 *  Pointer to null-terminated buffer allocated by memget.
 *  *SIZE is set to the length of the buffer.
 *
 */

char *
irs_irp_read_body(struct irp_p *pvt, size_t *size) {
    char line[1024];
    u_int linelen;
    size_t len = LINEINCR;
    char *buffer = memget(len);
    int idx = 0;

    if (buffer == NULL)
        return (NULL);

    for (;;) {
        if (irs_irp_read_line(pvt, line, sizeof line) <= 0 ||
            strchr(line, '\n') == NULL)
            goto death;

        linelen = strlen(line);

        if (line[linelen - 1] != '\n')
            goto death;

        /* We're not strict about missing \r. Should we be??  */
        if (linelen > 2 && line[linelen - 2] == '\r') {
            line[linelen - 2] = '\n';
            line[linelen - 1] = '\0';
            linelen--;
        }

        if (linelen == 2 && line[0] == '.') {
            *size = len;
            buffer[idx] = '\0';

            return (buffer);
        }

        if (linelen > (len - (idx + 1))) {
            char *p = memget(len + LINEINCR);

            if (p == NULL)
                goto death;
            memcpy(p, buffer, len);
            memput(buffer, len);
            buffer = p;
            len += LINEINCR;
        }

        memcpy(buffer + idx, line, linelen);
        idx += linelen;
    }
 death:
    memput(buffer, len);
    return (NULL);
}

/*%
 * int irs_irp_get_full_response(struct irp_p *pvt, int *code,
 *          char **body, size_t *bodylen);
 *
 *  Gets the response to a command. If the response indicates
 *  there's a body to follow(code % 10 == 1), then the
 *  body buffer is allcoated with memget and stored in
 *  *BODY. The length of the allocated body buffer is stored
 *  in *BODY. The caller must give the body buffer back to
 *  memput when done. The results code is stored in *CODE.
 *
 * Returns:
 *
 *  0 if a result was read. -1 on some sort of failure.
 *
 */

int
irs_irp_get_full_response(struct irp_p *pvt, int *code, char *text,
              size_t textlen, char **body, size_t *bodylen) {
    int result = irs_irp_read_response(pvt, text, textlen);

    *body = NULL;

    if (result == 0) {
        return (-1);
    }

    *code = result;

    /* Code that matches 2xx is a good result code.
     * Code that matches xx1 means there's a response body coming.
     */
    if ((result / 100) == 2 && (result % 10) == 1) {
        *body = irs_irp_read_body(pvt, bodylen);
        if (*body == NULL) {
            return (-1);
        }
    }

    return (0);
}

/*%
 * int irs_irp_send_command(struct irp_p *pvt, const char *fmt, ...);
 *
 *  Sends command to remote connected via the PVT
 *  structure. FMT and args after it are fprintf-like
 *  arguments for formatting.
 *
 * Returns:
 *
 *  0 on success, -1 on failure.
 */

int
irs_irp_send_command(struct irp_p *pvt, const char *fmt, ...) {
    va_list ap;
    char buffer[1024];
    int pos = 0;
    int i, todo;


    if (pvt->fdCxn < 0) {
        return (-1);
    }

    va_start(ap, fmt);
    (void) vsprintf(buffer, fmt, ap);
    todo = strlen(buffer);
    va_end(ap);
    if (todo > (int)sizeof(buffer) - 3) {
        syslog(LOG_CRIT, "memory overrun in irs_irp_send_command()");
        exit(1);
    }
    strcat(buffer, "\r\n");
    todo = strlen(buffer);

    while (todo > 0) {
        i = write(pvt->fdCxn, buffer + pos, todo);
#if 0
        /* XXX brister */
        fprintf(stderr, "Wrote: \"");
        fwrite(buffer + pos, sizeof (char), todo, stderr);
        fprintf(stderr, "\"\n");
#endif
        if (i < 0) {
            close(pvt->fdCxn);
            pvt->fdCxn = -1;
            return (-1);
        }
        todo -= i;
    }

    return (0);
}


/* Methods */

/*%
 * void irp_close(struct irs_acc *this)
 *
 */

static void
irp_close(struct irs_acc *this) {
    struct irp_p *irp = (struct irp_p *)this->private;

    if (irp != NULL) {
        irs_irp_disconnect(irp);
        memput(irp, sizeof *irp);
    }

    memput(this, sizeof *this);
}


/*! \file */