cregit-Linux how code gets into the kernel

Release 4.14 arch/um/drivers/mconsole_user.c

Directory: arch/um/drivers
/*
 * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org)
 * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
 * Licensed under the GPL
 */

#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/uio.h>
#include <sys/un.h>
#include "mconsole.h"


static struct mconsole_command commands[] = {
	/*
         * With uts namespaces, uts information becomes process-specific, so
         * we need a process context.  If we try handling this in interrupt
         * context, we may hit an exiting process without a valid uts
         * namespace.
         */
	{ "version", mconsole_version, MCONSOLE_PROC },
	{ "halt", mconsole_halt, MCONSOLE_PROC },
	{ "reboot", mconsole_reboot, MCONSOLE_PROC },
	{ "config", mconsole_config, MCONSOLE_PROC },
	{ "remove", mconsole_remove, MCONSOLE_PROC },
	{ "sysrq", mconsole_sysrq, MCONSOLE_INTR },
	{ "help", mconsole_help, MCONSOLE_INTR },
	{ "cad", mconsole_cad, MCONSOLE_INTR },
	{ "stop", mconsole_stop, MCONSOLE_PROC },
	{ "go", mconsole_go, MCONSOLE_INTR },
	{ "log", mconsole_log, MCONSOLE_INTR },
	{ "proc", mconsole_proc, MCONSOLE_PROC },
	{ "stack", mconsole_stack, MCONSOLE_INTR },
};

/* Initialized in mconsole_init, which is an initcall */

char mconsole_socket_name[256];


static int mconsole_reply_v0(struct mc_request *req, char *reply) { struct iovec iov; struct msghdr msg; iov.iov_base = reply; iov.iov_len = strlen(reply); msg.msg_name = &(req->origin); msg.msg_namelen = req->originlen; msg.msg_iov = &iov; msg.msg_iovlen = 1; msg.msg_control = NULL; msg.msg_controllen = 0; msg.msg_flags = 0; return sendmsg(req->originating_fd, &msg, 0); }

Contributors

PersonTokensPropCommitsCommitProp
Jeff Dike10099.01%150.00%
Américo Wang10.99%150.00%
Total101100.00%2100.00%


static struct mconsole_command *mconsole_parse(struct mc_request *req) { struct mconsole_command *cmd; int i; for (i = 0; i < ARRAY_SIZE(commands); i++) { cmd = &commands[i]; if (!strncmp(req->request.data, cmd->command, strlen(cmd->command))) { return cmd; } } return NULL; }

Contributors

PersonTokensPropCommitsCommitProp
Jeff Dike78100.00%2100.00%
Total78100.00%2100.00%

#define MIN(a,b) ((a)<(b) ? (a):(b)) #define STRINGX(x) #x #define STRING(x) STRINGX(x)
int mconsole_get_request(int fd, struct mc_request *req) { int len; req->originlen = sizeof(req->origin); req->len = recvfrom(fd, &req->request, sizeof(req->request), 0, (struct sockaddr *) req->origin, &req->originlen); if (req->len < 0) return 0; req->originating_fd = fd; if (req->request.magic != MCONSOLE_MAGIC) { /* Unversioned request */ len = MIN(sizeof(req->request.data) - 1, strlen((char *) &req->request)); memmove(req->request.data, &req->request, len); req->request.data[len] = '\0'; req->request.magic = MCONSOLE_MAGIC; req->request.version = 0; req->request.len = len; mconsole_reply_v0(req, "ERR Version 0 mconsole clients are " "not supported by this driver"); return 0; } if (req->request.len >= MCONSOLE_MAX_DATA) { mconsole_reply(req, "Request too large", 1, 0); return 0; } if (req->request.version != MCONSOLE_VERSION) { mconsole_reply(req, "This driver only supports version " STRING(MCONSOLE_VERSION) " clients", 1, 0); } req->request.data[req->request.len] = '\0'; req->cmd = mconsole_parse(req); if (req->cmd == NULL) { mconsole_reply(req, "Unknown command", 1, 0); return 0; } return 1; }

Contributors

PersonTokensPropCommitsCommitProp
Jeff Dike28899.65%150.00%
Karol Swietlicki10.35%150.00%
Total289100.00%2100.00%


int mconsole_reply_len(struct mc_request *req, const char *str, int total, int err, int more) { /* * XXX This is a stack consumption problem. It'd be nice to * make it global and serialize access to it, but there are a * ton of callers to this function. */ struct mconsole_reply reply; int len, n; do { reply.err = err; /* err can only be true on the first packet */ err = 0; len = MIN(total, MCONSOLE_MAX_DATA - 1); if (len == total) reply.more = more; else reply.more = 1; memcpy(reply.data, str, len); reply.data[len] = '\0'; total -= len; str += len; reply.len = len + 1; len = sizeof(reply) + reply.len - sizeof(reply.data); n = sendto(req->originating_fd, &reply, len, 0, (struct sockaddr *) req->origin, req->originlen); if (n < 0) return -errno; } while (total > 0); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Jeff Dike17797.79%375.00%
Paolo 'Blaisorblade' Giarrusso42.21%125.00%
Total181100.00%4100.00%


int mconsole_reply(struct mc_request *req, const char *str, int err, int more) { return mconsole_reply_len(req, str, strlen(str), err, more); }

Contributors

PersonTokensPropCommitsCommitProp
Jeff Dike38100.00%1100.00%
Total38100.00%1100.00%


int mconsole_unlink_socket(void) { unlink(mconsole_socket_name); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Jeff Dike15100.00%1100.00%
Total15100.00%1100.00%

static int notify_sock = -1;
int mconsole_notify(char *sock_name, int type, const void *data, int len) { struct sockaddr_un target; struct mconsole_notify packet; int n, err = 0; lock_notify(); if (notify_sock < 0) { notify_sock = socket(PF_UNIX, SOCK_DGRAM, 0); if (notify_sock < 0) { err = -errno; printk(UM_KERN_ERR "mconsole_notify - socket failed, " "errno = %d\n", errno); } } unlock_notify(); if (err) return err; target.sun_family = AF_UNIX; strcpy(target.sun_path, sock_name); packet.magic = MCONSOLE_MAGIC; packet.version = MCONSOLE_VERSION; packet.type = type; len = (len > sizeof(packet.data)) ? sizeof(packet.data) : len; packet.len = len; memcpy(packet.data, data, len); err = 0; len = sizeof(packet) + packet.len - sizeof(packet.data); n = sendto(notify_sock, &packet, len, 0, (struct sockaddr *) &target, sizeof(target)); if (n < 0) { err = -errno; printk(UM_KERN_ERR "mconsole_notify - sendto failed, " "errno = %d\n", errno); } return err; }

Contributors

PersonTokensPropCommitsCommitProp
Jeff Dike235100.00%4100.00%
Total235100.00%4100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Jeff Dike107897.20%866.67%
Paolo 'Blaisorblade' Giarrusso292.61%216.67%
Karol Swietlicki10.09%18.33%
Américo Wang10.09%18.33%
Total1109100.00%12100.00%
Directory: arch/um/drivers
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.