X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=daemon%2Fguestfsd.c;h=61a62368a0c5731fbb14c55ecc98af59a7f90baa;hp=af554bf7c3814771bdf2984c534a25700f919590;hb=627f89351d06e43564b47ea42cabaa522284c2a1;hpb=d17bd636a8114498aa27ffd4d0dd38a1822fe7cd diff --git a/daemon/guestfsd.c b/daemon/guestfsd.c index af554bf..61a6236 100644 --- a/daemon/guestfsd.c +++ b/daemon/guestfsd.c @@ -34,17 +34,19 @@ #include #include #include -#include #include #include +#include "c-ctype.h" +#include "ignore-value.h" + #include "daemon.h" -static void usage (void); +static char *read_cmdline (void); /* Also in guestfs.c */ -#define VMCHANNEL_PORT "6666" -#define VMCHANNEL_ADDR "10.0.2.4" +#define GUESTFWD_ADDR "10.0.2.4" +#define GUESTFWD_PORT "6666" int verbose = 0; @@ -64,30 +66,28 @@ static int print_arginfo (const struct printf_info *info, size_t n, int *argtype const char *sysroot = "/sysroot"; /* No trailing slash. */ int sysroot_len = 8; +static void +usage (void) +{ + fprintf (stderr, + "guestfsd [-f|--foreground] [-c|--channel vmchannel] [-v|--verbose]\n"); +} + int main (int argc, char *argv[]) { - static const char *options = "fh:p:?"; + static const char *options = "fc:v?"; static const struct option long_options[] = { + { "channel", required_argument, 0, 'c' }, { "foreground", 0, 0, 'f' }, { "help", 0, 0, '?' }, - { "host", 1, 0, 'h' }, - { "port", 1, 0, 'p' }, + { "verbose", 0, 0, 'v' }, { 0, 0, 0, 0 } }; - int c, n, r; + int c; int dont_fork = 0; - const char *host = NULL; - const char *port = NULL; - FILE *fp; - char buf[4096]; - char *p, *p2; - int sock; - struct addrinfo *res, *rr; - struct addrinfo hints; - XDR xdr; - uint32_t len; - struct sigaction sa; + char *cmdline; + char *vmchannel = NULL; #ifdef HAVE_REGISTER_PRINTF_SPECIFIER /* http://udrepper.livejournal.com/20948.html */ @@ -107,16 +107,16 @@ main (int argc, char *argv[]) if (c == -1) break; switch (c) { - case 'f': - dont_fork = 1; + case 'c': + vmchannel = optarg; break; - case 'h': - host = optarg; + case 'f': + dont_fork = 1; break; - case 'p': - port = optarg; + case 'v': + verbose = 1; break; case '?': @@ -134,48 +134,23 @@ main (int argc, char *argv[]) exit (1); } - /* If host and port aren't set yet, try /proc/cmdline. */ - if (!host || !port) { - fp = fopen ("/proc/cmdline", "r"); - if (fp == NULL) { - perror ("/proc/cmdline"); - goto next; - } - n = fread (buf, 1, sizeof buf - 1, fp); - fclose (fp); - buf[n] = '\0'; - - /* Set the verbose flag. Not quite right because this will only - * set the flag if host and port aren't set on the command line. - * Don't worry about this for now. (XXX) - */ - verbose = strstr (buf, "guestfs_verbose=1") != NULL; - if (verbose) - printf ("verbose daemon enabled\n"); + cmdline = read_cmdline (); - p = strstr (buf, "guestfs="); + /* Set the verbose flag. */ + verbose = verbose || + (cmdline && strstr (cmdline, "guestfs_verbose=1") != NULL); + if (verbose) + printf ("verbose daemon enabled\n"); - if (p) { - p += 8; - p2 = strchr (p, ':'); - if (p2) { - *p2++ = '\0'; - host = p; - r = strcspn (p2, " \n"); - p2[r] = '\0'; - port = p2; - } - } - } - - next: - /* Can't parse /proc/cmdline, so use built-in defaults. */ - if (!host || !port) { - host = VMCHANNEL_ADDR; - port = VMCHANNEL_PORT; + if (verbose) { + if (cmdline) + printf ("linux commmand line: %s\n", cmdline); + else + printf ("could not read linux command line\n"); } /* Make sure SIGPIPE doesn't kill us. */ + struct sigaction sa; memset (&sa, 0, sizeof sa); sa.sa_handler = SIG_IGN; sa.sa_flags = 0; @@ -193,47 +168,143 @@ main (int argc, char *argv[]) /* We document that umask defaults to 022 (it should be this anyway). */ umask (022); - /* Resolve the hostname. */ - memset (&hints, 0, sizeof hints); - hints.ai_socktype = SOCK_STREAM; - hints.ai_flags = AI_ADDRCONFIG; - r = getaddrinfo (host, port, &hints, &res); - if (r != 0) { - fprintf (stderr, "%s:%s: %s\n", host, port, gai_strerror (r)); - exit (1); + /* Get the vmchannel string. + * + * Sources: + * --channel/-c option on the command line + * guestfs_vmchannel=... from the kernel command line + * guestfs=... from the kernel command line + * built-in default + * + * At the moment we expect this to contain "tcp:ip:port" but in + * future it might contain a device name, eg. "/dev/vcon4" for + * virtio-console vmchannel. + */ + if (vmchannel == NULL && cmdline) { + char *p; + size_t len; + + p = strstr (cmdline, "guestfs_vmchannel="); + if (p) { + len = strcspn (p + 18, " \t\n"); + vmchannel = strndup (p + 18, len); + if (!vmchannel) { + perror ("strndup"); + exit (1); + } + } + + /* Old libraries passed guestfs=host:port. Rewrite it as tcp:host:port. */ + if (vmchannel == NULL) { + /* We will rewrite it part of the "guestfs=" string with + * "tcp:" hence p + 4 below. */ + p = strstr (cmdline, "guestfs="); + if (p) { + len = strcspn (p + 4, " \t\n"); + vmchannel = strndup (p + 4, len); + if (!vmchannel) { + perror ("strndup"); + exit (1); + } + memcpy (vmchannel, "tcp:", 4); + } + } } - /* Connect to the given TCP socket. */ - sock = -1; - for (rr = res; rr != NULL; rr = rr->ai_next) { - sock = socket (rr->ai_family, rr->ai_socktype, rr->ai_protocol); - if (sock != -1) { - if (connect (sock, rr->ai_addr, rr->ai_addrlen) == 0) - break; - perror ("connect"); + /* Default vmchannel. */ + if (vmchannel == NULL) { + vmchannel = strdup ("tcp:" GUESTFWD_ADDR ":" GUESTFWD_PORT); + if (!vmchannel) { + perror ("strdup"); + exit (1); + } + } - close (sock); - sock = -1; + if (verbose) + printf ("vmchannel: %s\n", vmchannel); + + /* Connect to vmchannel. */ + int sock = -1; + + if (strncmp (vmchannel, "tcp:", 4) == 0) { + /* Resolve the hostname. */ + struct addrinfo *res, *rr; + struct addrinfo hints; + int r; + char *host, *port; + + host = vmchannel+4; + port = strchr (host, ':'); + if (port) { + port[0] = '\0'; + port++; + } else { + fprintf (stderr, "vmchannel: expecting \"tcp::\": %s\n", + vmchannel); + exit (1); } + + memset (&hints, 0, sizeof hints); + hints.ai_socktype = SOCK_STREAM; + hints.ai_flags = AI_ADDRCONFIG; + r = getaddrinfo (host, port, &hints, &res); + if (r != 0) { + fprintf (stderr, "%s:%s: %s\n", + host, port, gai_strerror (r)); + exit (1); + } + + /* Connect to the given TCP socket. */ + for (rr = res; rr != NULL; rr = rr->ai_next) { + sock = socket (rr->ai_family, rr->ai_socktype, rr->ai_protocol); + if (sock != -1) { + if (connect (sock, rr->ai_addr, rr->ai_addrlen) == 0) + break; + perror ("connect"); + + close (sock); + sock = -1; + } + } + freeaddrinfo (res); + } else { + fprintf (stderr, + "unknown vmchannel connection type: %s\n" + "expecting \"tcp::\"\n", + vmchannel); + exit (1); } - freeaddrinfo (res); if (sock == -1) { - fprintf (stderr, "connection to %s:%s failed\n", host, port); + fprintf (stderr, + "\n" + "Failed to connect to any vmchannel implementation.\n" + "vmchannel: %s\n" + "\n" + "This is a fatal error and the appliance will now exit.\n" + "\n" + "Usually this error is caused by either QEMU or the appliance\n" + "kernel not supporting the vmchannel method that the\n" + "libguestfs library chose to use. Please run\n" + "'libguestfs-test-tool' and provide the complete, unedited\n" + "output to the libguestfs developers, either in a bug report\n" + "or on the libguestfs redhat com mailing list.\n" + "\n", + vmchannel); exit (1); } /* Send the magic length message which indicates that * userspace is up inside the guest. */ - len = GUESTFS_LAUNCH_FLAG; - xdrmem_create (&xdr, buf, sizeof buf, XDR_ENCODE); - if (!xdr_uint32_t (&xdr, &len)) { - fprintf (stderr, "xdr_uint32_t failed\n"); - exit (1); - } + char lenbuf[4]; + XDR xdr; + uint32_t len = GUESTFS_LAUNCH_FLAG; + xdrmem_create (&xdr, lenbuf, sizeof lenbuf, XDR_ENCODE); + xdr_uint32_t (&xdr, &len); - (void) xwrite (sock, buf, xdr_getpos (&xdr)); + if (xwrite (sock, lenbuf, sizeof lenbuf) == -1) + exit (1); xdr_destroy (&xdr); @@ -251,6 +322,55 @@ main (int argc, char *argv[]) exit (0); } +/* Read /proc/cmdline. */ +static char * +read_cmdline (void) +{ + int fd = open ("/proc/cmdline", O_RDONLY); + if (fd == -1) { + perror ("/proc/cmdline"); + return NULL; + } + + size_t len = 0; + ssize_t n; + char buf[256]; + char *r = NULL; + + for (;;) { + n = read (fd, buf, sizeof buf); + if (n == -1) { + perror ("read"); + free (r); + close (fd); + return NULL; + } + if (n == 0) + break; + char *newr = realloc (r, len + n + 1); /* + 1 is for terminating NUL */ + if (newr == NULL) { + perror ("realloc"); + free (r); + close (fd); + return NULL; + } + r = newr; + memcpy (&r[len], buf, n); + len += n; + } + + if (r) + r[len] = '\0'; + + if (close (fd) == -1) { + perror ("close"); + free (r); + return NULL; + } + + return r; +} + /* Turn "/path" into "/sysroot/path". * * Caller must check for NULL and call reply_with_perror ("malloc") @@ -314,12 +434,6 @@ xread (int sock, void *v_buf, size_t len) return 0; } -static void -usage (void) -{ - fprintf (stderr, "guestfsd [-f] [-h host -p port]\n"); -} - int add_string (char ***argv, int *size, int *alloc, const char *str) { @@ -396,13 +510,11 @@ free_stringslen (char **argv, int len) free (argv); } -/* This is a more sane version of 'system(3)' for running external - * commands. It uses fork/execvp, so we don't need to worry about - * quoting of parameters, and it allows us to capture any error - * messages in a buffer. +/* Easy ways to run external commands. For full documentation, see + * 'commandrvf' below. */ int -command (char **stdoutput, char **stderror, const char *name, ...) +commandf (char **stdoutput, char **stderror, int flags, const char *name, ...) { va_list args; const char **argv; @@ -436,7 +548,7 @@ command (char **stdoutput, char **stderror, const char *name, ...) va_end (args); - r = commandv (stdoutput, stderror, (char **) argv); + r = commandvf (stdoutput, stderror, flags, (const char * const*) argv); /* NB: Mustn't free the strings which are on the stack. */ free (argv); @@ -449,7 +561,7 @@ command (char **stdoutput, char **stderror, const char *name, ...) * We still return -1 if there was some other error. */ int -commandr (char **stdoutput, char **stderror, const char *name, ...) +commandrf (char **stdoutput, char **stderror, int flags, const char *name, ...) { va_list args; const char **argv; @@ -483,7 +595,7 @@ commandr (char **stdoutput, char **stderror, const char *name, ...) va_end (args); - r = commandrv (stdoutput, stderror, argv); + r = commandrvf (stdoutput, stderror, flags, argv); /* NB: Mustn't free the strings which are on the stack. */ free (argv); @@ -493,19 +605,43 @@ commandr (char **stdoutput, char **stderror, const char *name, ...) /* Same as 'command', but passing an argv. */ int -commandv (char **stdoutput, char **stderror, char *const *argv) +commandvf (char **stdoutput, char **stderror, int flags, + char const *const *argv) { int r; - r = commandrv (stdoutput, stderror, (void *) argv); + r = commandrvf (stdoutput, stderror, flags, (void *) argv); if (r == 0) return 0; else return -1; } +/* This is a more sane version of 'system(3)' for running external + * commands. It uses fork/execvp, so we don't need to worry about + * quoting of parameters, and it allows us to capture any error + * messages in a buffer. + * + * If stdoutput is not NULL, then *stdoutput will return the stdout + * of the command. + * + * If stderror is not NULL, then *stderror will return the stderr + * of the command. If there is a final \n character, it is removed + * so you can use the error string directly in a call to + * reply_with_error. + * + * Flags: + * + * COMMAND_FLAG_FOLD_STDOUT_ON_STDERR: For broken external commands + * that send error messages to stdout (hello, parted) but that don't + * have any useful stdout information, use this flag to capture the + * error messages in the *stderror buffer. If using this flag, + * you should pass stdoutput as NULL because nothing could ever be + * captured in that buffer. + */ int -commandrv (char **stdoutput, char **stderror, char const* const *argv) +commandrvf (char **stdoutput, char **stderror, int flags, + char const* const *argv) { int so_size = 0, se_size = 0; int so_fd[2], se_fd[2]; @@ -542,9 +678,13 @@ commandrv (char **stdoutput, char **stderror, char const* const *argv) if (pid == 0) { /* Child process. */ close (0); + open ("/dev/null", O_RDONLY); /* Set stdin to /dev/null (ignore failure) */ close (so_fd[0]); close (se_fd[0]); - dup2 (so_fd[1], 1); + if (!(flags & COMMAND_FLAG_FOLD_STDOUT_ON_STDERR)) + dup2 (so_fd[1], 1); + else + dup2 (se_fd[1], 1); dup2 (se_fd[1], 2); close (so_fd[1]); close (se_fd[1]); @@ -605,15 +745,20 @@ commandrv (char **stdoutput, char **stderror, char const* const *argv) } if (r == 0) { FD_CLR (se_fd[0], &rset); quit++; } - if (r > 0 && stderror) { - se_size += r; - p = realloc (*stderror, se_size); - if (p == NULL) { - perror ("realloc"); - goto quit; + if (r > 0) { + if (verbose) + ignore_value (write (2, buf, r)); + + if (stderror) { + se_size += r; + p = realloc (*stderror, se_size); + if (p == NULL) { + perror ("realloc"); + goto quit; + } + *stderror = p; + memcpy (*stderror + se_size - r, buf, r); } - *stderror = p; - memcpy (*stderror + se_size - r, buf, r); } } } @@ -723,7 +868,7 @@ print_shell_quote (FILE *stream, const struct printf_info *info ATTRIBUTE_UNUSED, const void *const *args) { -#define SAFE(c) (isalnum((c)) || \ +#define SAFE(c) (c_isalnum((c)) || \ (c) == '/' || (c) == '-' || (c) == '_' || (c) == '.') int i, len; const char *str = *((const char **) (args[0])); @@ -800,7 +945,7 @@ device_name_translation (char *device, const char *func) } /* If the name begins with "/dev/sd" then try the alternatives. */ - if (strncmp (device, "/dev/sd", 7) != 0) + if (STRNEQLEN (device, "/dev/sd", 7)) goto error; device[5] = 'h'; /* /dev/hd (old IDE driver) */