From fd888e850cf413955483bfb993aeeea5ea611289 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 17 Apr 2024 10:06:26 +0200 Subject: Adding debian version 2:2.6.1-4~deb12u2. Signed-off-by: Daniel Baumann --- debian/askpass.c | 573 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 573 insertions(+) create mode 100644 debian/askpass.c (limited to 'debian/askpass.c') diff --git a/debian/askpass.c b/debian/askpass.c new file mode 100644 index 0000000..07826de --- /dev/null +++ b/debian/askpass.c @@ -0,0 +1,573 @@ +/* + * askpass.c - prompts a user for a passphrase using any suitable method + * and prints the result to stdout. + * + * Copyright (C) 2008 David Härdeman + * + * This package is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This package is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this package; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + + +#define _GNU_SOURCE +#define _DEFAULT_SOURCE +#define _POSIX_C_SOURCE 1 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define DEBUG 0 + +#define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0])) + +static bool disable_method(const char *method); + +/***************************************************************************** + * Utility functions * + *****************************************************************************/ +static void +debug(const char *fmt, ...) +{ + va_list ap; + static bool first = true; + static FILE *dbgfile; + + if (!DEBUG) + return; + + if (first) { + first = false; + dbgfile = fopen("/tmp/askpass.debug", "a"); + } + + if (!dbgfile) + return; + + va_start(ap, fmt); + vfprintf(dbgfile, fmt, ap); + va_end(ap); +} + +static void +usage(const char *arg0, const char *errmsg) +{ + if (errmsg) + fprintf(stderr, "Error: %s\nUsage: %s PROMPT\n", errmsg, arg0); + else + fprintf(stderr, "Usage: %s PROMPT\n", arg0); + exit(EXIT_FAILURE); +} + +static void +fifo_common_finish(int fd, char **buf, size_t *used, size_t *size) +{ + if (fd >= 0) + close(fd); + + if (!*buf) + return; + + memset(*buf, '\0', *size); + free(*buf); + *buf = NULL; + *used = 0; + *size = 0; +} + +static bool +fifo_common_read(int fd, char **buf, size_t *used, size_t *size) +{ + ssize_t result; + +again: + if ((*size - *used) == 0) { + *size += 4096; + *buf = realloc(*buf, *size); + if (!*buf) { + *size = 0; + *used = 0; + debug("Failed to allocate memory for passphrase\n"); + return false; + } + } + +reread: + result = read(fd, *buf + *used, *size - *used); + + if (result < 0) { + if (errno == EAGAIN) + return false; + if (errno == EINTR) + goto reread; + debug("Error when reading from fifo\n"); + return false; + } + + debug("Read %i bytes from fifo\n", (int)result); + *used += result; + + if (result == 0) + return true; + + goto again; +} + +/***************************************************************************** + * systemd functions * + *****************************************************************************/ + +#define SYSTEMD_ASKPASS "/bin/systemd-ask-password" +static pid_t systemdpid; +static size_t systemdused = 0; +static size_t systemdsize = 0; +static char *systemdbuf = NULL; + +static int +systemd_prepare(const char *prompt) +{ + struct stat a, b; + int pipefds[2]; + + /* is systemd running? */ + if (lstat("/sys/fs/cgroup", &a) < 0) + return -1; + if (lstat("/sys/fs/cgroup/systemd", &b) < 0) + return -1; + if (a.st_dev == b.st_dev) + return -1; + + if (access(SYSTEMD_ASKPASS, X_OK)) + return -1; + + if (pipe(pipefds)) + return -1; + + systemdpid = fork(); + if (systemdpid < 0) { + close(pipefds[0]); + close(pipefds[1]); + return -1; + } + + if (systemdpid == 0) { + close(pipefds[0]); + if (dup2(pipefds[1], STDOUT_FILENO) < 0) + exit(EXIT_FAILURE); + execl(SYSTEMD_ASKPASS, SYSTEMD_ASKPASS, + "--timeout=0", prompt, (char*)NULL); + exit(EXIT_FAILURE); + } + + close(pipefds[1]); + return pipefds[0]; +} + +static bool +systemd_read(int fd, char **buf, size_t *size) +{ + debug("In systemd_read\n"); + if (fifo_common_read(fd, &systemdbuf, &systemdused, &systemdsize)) { + /* systemd likes to include the terminating newline */ + if (systemdused >= 1 && systemdbuf[systemdused - 1] == '\n') { + systemdbuf[systemdused - 1] = '\0'; + systemdused--; + } + *buf = systemdbuf; + *size = systemdused; + return true; + } + + return false; +} + +static void +systemd_finish(int fd) +{ + kill(systemdpid, SIGTERM); + fifo_common_finish(fd, &systemdbuf, &systemdused, &systemdsize); +} + +/***************************************************************************** + * plymouth functions * + *****************************************************************************/ + +#define PLYMOUTH_PATH "/bin/plymouth" +static pid_t plymouthpid; +static size_t plymouthused = 0; +static size_t plymouthsize = 0; +static char *plymouthbuf = NULL; + +static int +plymouth_prepare(const char *prompt) +{ + int pipefds[2]; + + if (access(PLYMOUTH_PATH, X_OK)) + return -1; + + if (system(PLYMOUTH_PATH" --ping")) + return -1; + + /* Plymouth will add a ':' if it is a non-graphical prompt */ + char *prompt2 = strdup(prompt); + int len = strlen(prompt2); + if (len > 1 && prompt2[len-2] == ':' && prompt2[len - 1] == ' ') + prompt2[len - 2] = '\0'; + else if (len > 0 && prompt2[len - 1] == ':') + prompt2[len - 1] = '\0'; + + if (pipe(pipefds)) + return -1; + + plymouthpid = fork(); + if (plymouthpid < 0) { + close(pipefds[0]); + close(pipefds[1]); + return -1; + } + + if (plymouthpid == 0) { + close(pipefds[0]); + if (dup2(pipefds[1], STDOUT_FILENO) < 0) + exit(EXIT_FAILURE); + execl(PLYMOUTH_PATH, PLYMOUTH_PATH, + "ask-for-password", "--prompt", prompt2, (char*)NULL); + exit(EXIT_FAILURE); + } + free(prompt2); + + close(pipefds[1]); + return pipefds[0]; +} + +static bool +plymouth_read(int fd, char **buf, size_t *size) +{ + debug("In plymouth_read\n"); + if (fifo_common_read(fd, &plymouthbuf, &plymouthused, &plymouthsize)) { + *buf = plymouthbuf; + *size = plymouthused; + return true; + } + + return false; +} + +static void +plymouth_finish(int fd) +{ + kill(plymouthpid, SIGKILL); + fifo_common_finish(fd, &plymouthbuf, &plymouthused, &plymouthsize); +} + +/***************************************************************************** + * fifo functions * + *****************************************************************************/ +#define FIFO_PATH "/lib/cryptsetup/passfifo" +static size_t fifoused = 0; +static size_t fifosize = 0; +static char *fifobuf = NULL; + +static void +fifo_finish(int fd) +{ + fifo_common_finish(fd, &fifobuf, &fifoused, &fifosize); +} + +static bool +fifo_read(int fd, char **buf, size_t *size) +{ + debug("In fifo_read\n"); + if (fifo_common_read(fd, &fifobuf, &fifoused, &fifosize)) { + *buf = fifobuf; + *size = fifoused; + return true; + } + + return false; +} + +static int +fifo_prepare(const char *prompt) +{ + int ret; + + ret = mkfifo(FIFO_PATH, 0600); + if (ret && errno != EEXIST) + return -1; + + return open(FIFO_PATH, O_RDONLY | O_NONBLOCK); +} + +/***************************************************************************** + * console functions * + *****************************************************************************/ +#define CONSOLE_PATH "/dev/console" +static struct termios term_old; +static bool term_set = false; +static char *consolebuf = NULL; +static size_t consolebuflen = 0; + +static void +console_finish(int fd) +{ + if (consolebuf) { + memset(consolebuf, '\0', consolebuflen); + free(consolebuf); + consolebuf = NULL; + consolebuflen = 0; + } + + if (!term_set || fd < 0) + return; + + term_set = false; + tcsetattr(fd, TCSAFLUSH, &term_old); + fprintf(stderr, "\n"); + klogctl(7, NULL, 0); +} + +bool +console_read(int fd, char **buf, size_t *size) +{ + ssize_t nread; + + /* Console is in ICANON mode so we'll get entire lines */ + nread = getline(&consolebuf, &consolebuflen, stdin); + + if (nread < 0) { + clearerr(stdin); + return false; + } + + /* Strip trailing newline, if any */ + if (nread > 0 && consolebuf[nread - 1] == '\n') { + nread--; + consolebuf[nread] = '\0'; + } + + *size = nread; + *buf = consolebuf; + + return true; +} + +static int +console_prepare(const char *prompt) +{ + struct termios term_new; + const char *prompt_ptr = prompt; + char *newline = NULL; + + if (!isatty(STDIN_FILENO)) { + if (access(CONSOLE_PATH, R_OK | W_OK)) { + debug("No access to console device " CONSOLE_PATH "\n"); + return -1; + } + + if (!freopen(CONSOLE_PATH, "r", stdin) || + !freopen(CONSOLE_PATH, "a", stdout) || + !freopen(CONSOLE_PATH, "a", stderr) || + !isatty(STDIN_FILENO)) { + debug("Failed to open console\n"); + return -1; + } + } + + if (tcgetattr(STDIN_FILENO, &term_old)) { + debug("Failed to get terminal settings\n"); + return -1; + } + + term_new = term_old; + term_new.c_lflag &= ~ECHO; + term_new.c_lflag |= ICANON; + + if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &term_new)) { + debug("Failed to disable echoing\n"); + return -1; + } + + /* handle any non-literal embedded newlines in prompt */ + while ( (newline = strstr(prompt_ptr,"\\n")) != NULL ) { + /* Calculate length of string leading up to newline. */ + int line_len = newline - prompt_ptr; + + /* Force trimming of prompt to location of newline. */ + if (fwrite(prompt_ptr, line_len, 1, stderr) < 1 || + fwrite("\n", 1, 1, stderr) < 1) { + debug("Failed to print prompt\n"); + tcsetattr(STDIN_FILENO, TCSAFLUSH, &term_old); + return -1; + } + + /* Skip over newline. */ + prompt_ptr = newline + 2; + } + if (fputs(prompt_ptr, stderr) < 0) { + debug("Failed to print prompt\n"); + tcsetattr(STDIN_FILENO, TCSAFLUSH, &term_old); + return -1; + } + + /* Disable printk to console */ + klogctl(6, NULL, 0); + term_set = true; + return STDIN_FILENO; +} + +/***************************************************************************** + * main functions * + *****************************************************************************/ + +struct method { + const char *name; + int (*prepare)(const char *prompt); + bool (*read)(int fd, char **buf, size_t *size); + void (*finish)(int fd); + bool no_more; + bool active; + bool enabled; + int fd; +}; + +static struct method methods[] = { + { "systemd", systemd_prepare, systemd_read, systemd_finish, true, false, true, -1 }, + { "fifo", fifo_prepare, fifo_read, fifo_finish, false, false, true, -1 }, + { "plymouth", plymouth_prepare, plymouth_read, plymouth_finish, true, false, true, -1 }, + { "console", console_prepare, console_read, console_finish, false, false, true, -1 } +}; + +static bool +disable_method(const char *method) +{ + int i; + bool result = false; + + debug("Disabling method %s\n", method ? method : "ALL"); + + for (i = 0; i < ARRAY_SIZE(methods); i++) { + /* A NULL method means all methods should be disabled */ + if (method && strcmp(methods[i].name, method)) + continue; + if (!methods[i].enabled) + continue; + if (methods[i].active) + methods[i].finish(methods[i].fd); + + methods[i].active = false; + methods[i].fd = -1; + methods[i].enabled = false; + result = true; + } + + return result; +} + +int +main(int argc, char **argv, char **envp) +{ + char *pass = NULL; + size_t passlen = 0; + int i; + int nfds; + fd_set fds; + int ret; + bool done = false; + sigset_t sigset; + + if (argc != 2) + usage(argv[0], "incorrect number of arguments"); + + sigfillset(&sigset); + sigprocmask(SIG_BLOCK, &sigset, NULL); + + for (i = 0; i < ARRAY_SIZE(methods); i++) { + if (!methods[i].enabled) + continue; + debug("Enabling method %s\n", methods[i].name); + methods[i].fd = methods[i].prepare(argv[1]); + if (methods[i].fd < 0) { + methods[i].active = false; + methods[i].enabled = false; + } else { + methods[i].active = true; + methods[i].enabled = true; + if (methods[i].no_more) + break; + } + } + + while (!done) { + nfds = 0; + FD_ZERO(&fds); + for (i = 0; i < ARRAY_SIZE(methods); i++) { + if (!methods[i].enabled || methods[i].fd < 0) + continue; + debug("method %i has fd %i and name %s\n", i, methods[i].fd, methods[i].name); + FD_SET(methods[i].fd, &fds); + if (methods[i].fd + 1 > nfds) + nfds = methods[i].fd + 1; + } + + if (nfds == 0) { + debug("All methods disabled\n"); + exit(EXIT_FAILURE); + } + + debug("Starting select with nfds %i\n", nfds); + ret = select(nfds, &fds, NULL, NULL, NULL); + + if (ret <= 0) { + if (ret == 0 || errno == EINTR) + continue; + debug("Select failed\n"); + disable_method(NULL); + exit(EXIT_FAILURE); + } + + for (i = 0; i < ARRAY_SIZE(methods); i++) { + if (!methods[i].enabled || methods[i].fd < 0) + continue; + if (!FD_ISSET(methods[i].fd, &fds)) + continue; + if (methods[i].read(methods[i].fd, &pass, &passlen) && pass) { + done = true; + break; + } + } + } + + debug("Writing %i bytes to stdout\n", (int)passlen); + if (write(STDOUT_FILENO, pass, passlen) == -1) { + disable_method(NULL); + exit(EXIT_FAILURE); + } + disable_method(NULL); + exit(EXIT_SUCCESS); +} + -- cgit v1.2.3