Update decrypt for 4.4

Change-Id: I8d5d7b6a49890e4707d70de8b429563de0d2ad99
diff --git a/crypto/logwrapper/logwrap.c b/crypto/logwrapper/logwrap.c
new file mode 100644
index 0000000..4ca1db4
--- /dev/null
+++ b/crypto/logwrapper/logwrap.c
@@ -0,0 +1,569 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <string.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <poll.h>
+#include <sys/wait.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <libgen.h>
+#include <stdbool.h>
+#include <pthread.h>
+
+#include <logwrap/logwrap.h>
+#include "private/android_filesystem_config.h"
+#include "cutils/log.h"
+#include <cutils/klog.h>
+
+#define ARRAY_SIZE(x)   (sizeof(x) / sizeof(*(x)))
+#define MIN(a,b) (((a)<(b))?(a):(b))
+
+static pthread_mutex_t fd_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+#define ERROR(fmt, args...)                                                   \
+do {                                                                          \
+    fprintf(stderr, fmt, ## args);                                            \
+    ALOG(LOG_ERROR, "logwrapper", fmt, ## args);                              \
+} while(0)
+
+#define FATAL_CHILD(fmt, args...)                                             \
+do {                                                                          \
+    ERROR(fmt, ## args);                                                      \
+    _exit(-1);                                                                \
+} while(0)
+
+#define MAX_KLOG_TAG 16
+
+/* This is a simple buffer that holds up to the first beginning_buf->buf_size
+ * bytes of output from a command.
+ */
+#define BEGINNING_BUF_SIZE 0x1000
+struct beginning_buf {
+    char *buf;
+    size_t alloc_len;
+    /* buf_size is the usable space, which is one less than the allocated size */
+    size_t buf_size;
+    size_t used_len;
+};
+
+/* This is a circular buf that holds up to the last ending_buf->buf_size bytes
+ * of output from a command after the first beginning_buf->buf_size bytes
+ * (which are held in beginning_buf above).
+ */
+#define ENDING_BUF_SIZE 0x1000
+struct ending_buf {
+    char *buf;
+    ssize_t alloc_len;
+    /* buf_size is the usable space, which is one less than the allocated size */
+    ssize_t buf_size;
+    ssize_t used_len;
+    /* read and write offsets into the circular buffer */
+    int read;
+    int write;
+};
+
+ /* A structure to hold all the abbreviated buf data */
+struct abbr_buf {
+    struct beginning_buf b_buf;
+    struct ending_buf e_buf;
+    int beginning_buf_full;
+};
+
+/* Collect all the various bits of info needed for logging in one place. */
+struct log_info {
+    int log_target;
+    char klog_fmt[MAX_KLOG_TAG * 2];
+    char *btag;
+    bool abbreviated;
+    FILE *fp;
+    struct abbr_buf a_buf;
+};
+
+/* Forware declaration */
+static void add_line_to_abbr_buf(struct abbr_buf *a_buf, char *linebuf, int linelen);
+
+/* Return 0 on success, and 1 when full */
+static int add_line_to_linear_buf(struct beginning_buf *b_buf,
+                                   char *line, ssize_t line_len)
+{
+    size_t new_len;
+    char *new_buf;
+    int full = 0;
+
+    if ((line_len + b_buf->used_len) > b_buf->buf_size) {
+        full = 1;
+    } else {
+        /* Add to the end of the buf */
+        memcpy(b_buf->buf + b_buf->used_len, line, line_len);
+        b_buf->used_len += line_len;
+    }
+
+    return full;
+}
+
+static void add_line_to_circular_buf(struct ending_buf *e_buf,
+                                     char *line, ssize_t line_len)
+{
+    ssize_t free_len;
+    ssize_t needed_space;
+    char *new_buf;
+    int cnt;
+
+    if (e_buf->buf == NULL) {
+        return;
+    }
+
+   if (line_len > e_buf->buf_size) {
+       return;
+   }
+
+    free_len = e_buf->buf_size - e_buf->used_len;
+
+    if (line_len > free_len) {
+        /* remove oldest entries at read, and move read to make
+         * room for the new string */
+        needed_space = line_len - free_len;
+        e_buf->read = (e_buf->read + needed_space) % e_buf->buf_size;
+        e_buf->used_len -= needed_space;
+    }
+
+    /* Copy the line into the circular buffer, dealing with possible
+     * wraparound.
+     */
+    cnt = MIN(line_len, e_buf->buf_size - e_buf->write);
+    memcpy(e_buf->buf + e_buf->write, line, cnt);
+    if (cnt < line_len) {
+        memcpy(e_buf->buf, line + cnt, line_len - cnt);
+    }
+    e_buf->used_len += line_len;
+    e_buf->write = (e_buf->write + line_len) % e_buf->buf_size;
+}
+
+/* Log directly to the specified log */
+static void do_log_line(struct log_info *log_info, char *line) {
+    if (log_info->log_target & LOG_KLOG) {
+        klog_write(6, log_info->klog_fmt, line);
+    }
+    if (log_info->log_target & LOG_ALOG) {
+        ALOG(LOG_INFO, log_info->btag, "%s", line);
+    }
+    if (log_info->log_target & LOG_FILE) {
+        fprintf(log_info->fp, "%s\n", line);
+    }
+}
+
+/* Log to either the abbreviated buf, or directly to the specified log
+ * via do_log_line() above.
+ */
+static void log_line(struct log_info *log_info, char *line, int len) {
+    if (log_info->abbreviated) {
+        add_line_to_abbr_buf(&log_info->a_buf, line, len);
+    } else {
+        do_log_line(log_info, line);
+    }
+}
+
+/*
+ * The kernel will take a maximum of 1024 bytes in any single write to
+ * the kernel logging device file, so find and print each line one at
+ * a time.  The allocated size for buf should be at least 1 byte larger
+ * than buf_size (the usable size of the buffer) to make sure there is
+ * room to temporarily stuff a null byte to terminate a line for logging.
+ */
+static void print_buf_lines(struct log_info *log_info, char *buf, int buf_size)
+{
+    char *line_start;
+    char c;
+    int line_len;
+    int i;
+
+    line_start = buf;
+    for (i = 0; i < buf_size; i++) {
+        if (*(buf + i) == '\n') {
+            /* Found a line ending, print the line and compute new line_start */
+            /* Save the next char and replace with \0 */
+            c = *(buf + i + 1);
+            *(buf + i + 1) = '\0';
+            do_log_line(log_info, line_start);
+            /* Restore the saved char */
+            *(buf + i + 1) = c;
+            line_start = buf + i + 1;
+        } else if (*(buf + i) == '\0') {
+            /* The end of the buffer, print the last bit */
+            do_log_line(log_info, line_start);
+            break;
+        }
+    }
+    /* If the buffer was completely full, and didn't end with a newline, just
+     * ignore the partial last line.
+     */
+}
+
+static void init_abbr_buf(struct abbr_buf *a_buf) {
+    char *new_buf;
+
+    memset(a_buf, 0, sizeof(struct abbr_buf));
+    new_buf = malloc(BEGINNING_BUF_SIZE);
+    if (new_buf) {
+        a_buf->b_buf.buf = new_buf;
+        a_buf->b_buf.alloc_len = BEGINNING_BUF_SIZE;
+        a_buf->b_buf.buf_size = BEGINNING_BUF_SIZE - 1;
+    }
+    new_buf = malloc(ENDING_BUF_SIZE);
+    if (new_buf) {
+        a_buf->e_buf.buf = new_buf;
+        a_buf->e_buf.alloc_len = ENDING_BUF_SIZE;
+        a_buf->e_buf.buf_size = ENDING_BUF_SIZE - 1;
+    }
+}
+
+static void free_abbr_buf(struct abbr_buf *a_buf) {
+    free(a_buf->b_buf.buf);
+    free(a_buf->e_buf.buf);
+}
+
+static void add_line_to_abbr_buf(struct abbr_buf *a_buf, char *linebuf, int linelen) {
+    if (!a_buf->beginning_buf_full) {
+        a_buf->beginning_buf_full =
+            add_line_to_linear_buf(&a_buf->b_buf, linebuf, linelen);
+    }
+    if (a_buf->beginning_buf_full) {
+        add_line_to_circular_buf(&a_buf->e_buf, linebuf, linelen);
+    }
+}
+
+static void print_abbr_buf(struct log_info *log_info) {
+    struct abbr_buf *a_buf = &log_info->a_buf;
+
+    /* Add the abbreviated output to the kernel log */
+    if (a_buf->b_buf.alloc_len) {
+        print_buf_lines(log_info, a_buf->b_buf.buf, a_buf->b_buf.used_len);
+    }
+
+    /* Print an ellipsis to indicate that the buffer has wrapped or
+     * is full, and some data was not logged.
+     */
+    if (a_buf->e_buf.used_len == a_buf->e_buf.buf_size) {
+        do_log_line(log_info, "...\n");
+    }
+
+    if (a_buf->e_buf.used_len == 0) {
+        return;
+    }
+
+    /* Simplest way to print the circular buffer is allocate a second buf
+     * of the same size, and memcpy it so it's a simple linear buffer,
+     * and then cal print_buf_lines on it */
+    if (a_buf->e_buf.read < a_buf->e_buf.write) {
+        /* no wrap around, just print it */
+        print_buf_lines(log_info, a_buf->e_buf.buf + a_buf->e_buf.read,
+                        a_buf->e_buf.used_len);
+    } else {
+        /* The circular buffer will always have at least 1 byte unused,
+         * so by allocating alloc_len here we will have at least
+         * 1 byte of space available as required by print_buf_lines().
+         */
+        char * nbuf = malloc(a_buf->e_buf.alloc_len);
+        if (!nbuf) {
+            return;
+        }
+        int first_chunk_len = a_buf->e_buf.buf_size - a_buf->e_buf.read;
+        memcpy(nbuf, a_buf->e_buf.buf + a_buf->e_buf.read, first_chunk_len);
+        /* copy second chunk */
+        memcpy(nbuf + first_chunk_len, a_buf->e_buf.buf, a_buf->e_buf.write);
+        print_buf_lines(log_info, nbuf, first_chunk_len + a_buf->e_buf.write);
+        free(nbuf);
+    }
+}
+
+static int parent(const char *tag, int parent_read, pid_t pid,
+        int *chld_sts, int log_target, bool abbreviated, char *file_path) {
+    int status = 0;
+    char buffer[4096];
+    struct pollfd poll_fds[] = {
+        [0] = {
+            .fd = parent_read,
+            .events = POLLIN,
+        },
+    };
+    int rc = 0;
+    int fd;
+
+    struct log_info log_info;
+
+    int a = 0;  // start index of unprocessed data
+    int b = 0;  // end index of unprocessed data
+    int sz;
+    bool found_child = false;
+    char tmpbuf[256];
+
+    log_info.btag = basename(tag);
+    if (!log_info.btag) {
+        log_info.btag = (char*) tag;
+    }
+
+    if (abbreviated && (log_target == LOG_NONE)) {
+        abbreviated = 0;
+    }
+    if (abbreviated) {
+        init_abbr_buf(&log_info.a_buf);
+    }
+
+    if (log_target & LOG_KLOG) {
+        snprintf(log_info.klog_fmt, sizeof(log_info.klog_fmt),
+                 "<6>%.*s: %%s", MAX_KLOG_TAG, log_info.btag);
+    }
+
+    if ((log_target & LOG_FILE) && !file_path) {
+        /* No file_path specified, clear the LOG_FILE bit */
+        log_target &= ~LOG_FILE;
+    }
+
+    if (log_target & LOG_FILE) {
+        fd = open(file_path, O_WRONLY | O_CREAT, 0664);
+        if (fd < 0) {
+            ERROR("Cannot log to file %s\n", file_path);
+            log_target &= ~LOG_FILE;
+        } else {
+            lseek(fd, 0, SEEK_END);
+            log_info.fp = fdopen(fd, "a");
+        }
+    }
+
+    log_info.log_target = log_target;
+    log_info.abbreviated = abbreviated;
+
+    while (!found_child) {
+        if (TEMP_FAILURE_RETRY(poll(poll_fds, ARRAY_SIZE(poll_fds), -1)) < 0) {
+            ERROR("poll failed\n");
+            rc = -1;
+            goto err_poll;
+        }
+
+        if (poll_fds[0].revents & POLLIN) {
+            sz = read(parent_read, &buffer[b], sizeof(buffer) - 1 - b);
+
+            sz += b;
+            // Log one line at a time
+            for (b = 0; b < sz; b++) {
+                if (buffer[b] == '\r') {
+                    if (abbreviated) {
+                        /* The abbreviated logging code uses newline as
+                         * the line separator.  Lucikly, the pty layer
+                         * helpfully cooks the output of the command
+                         * being run and inserts a CR before NL.  So
+                         * I just change it to NL here when doing
+                         * abbreviated logging.
+                         */
+                        buffer[b] = '\n';
+                    } else {
+                        buffer[b] = '\0';
+                    }
+                } else if (buffer[b] == '\n') {
+                    buffer[b] = '\0';
+                    log_line(&log_info, &buffer[a], b - a);
+                    a = b + 1;
+                }
+            }
+
+            if (a == 0 && b == sizeof(buffer) - 1) {
+                // buffer is full, flush
+                buffer[b] = '\0';
+                log_line(&log_info, &buffer[a], b - a);
+                b = 0;
+            } else if (a != b) {
+                // Keep left-overs
+                b -= a;
+                memmove(buffer, &buffer[a], b);
+                a = 0;
+            } else {
+                a = 0;
+                b = 0;
+            }
+        }
+
+        if (poll_fds[0].revents & POLLHUP) {
+            int ret;
+
+            ret = waitpid(pid, &status, WNOHANG);
+            if (ret < 0) {
+                rc = errno;
+                ALOG(LOG_ERROR, "logwrap", "waitpid failed with %s\n", strerror(errno));
+                goto err_waitpid;
+            }
+            if (ret > 0) {
+                found_child = true;
+            }
+        }
+    }
+
+    if (chld_sts != NULL) {
+        *chld_sts = status;
+    } else {
+      if (WIFEXITED(status))
+        rc = WEXITSTATUS(status);
+      else
+        rc = -ECHILD;
+    }
+
+    // Flush remaining data
+    if (a != b) {
+      buffer[b] = '\0';
+      log_line(&log_info, &buffer[a], b - a);
+    }
+
+    /* All the output has been processed, time to dump the abbreviated output */
+    if (abbreviated) {
+        print_abbr_buf(&log_info);
+    }
+
+    if (WIFEXITED(status)) {
+      if (WEXITSTATUS(status)) {
+        snprintf(tmpbuf, sizeof(tmpbuf),
+                 "%s terminated by exit(%d)\n", log_info.btag, WEXITSTATUS(status));
+        do_log_line(&log_info, tmpbuf);
+      }
+    } else {
+      if (WIFSIGNALED(status)) {
+        snprintf(tmpbuf, sizeof(tmpbuf),
+                       "%s terminated by signal %d\n", log_info.btag, WTERMSIG(status));
+        do_log_line(&log_info, tmpbuf);
+      } else if (WIFSTOPPED(status)) {
+        snprintf(tmpbuf, sizeof(tmpbuf),
+                       "%s stopped by signal %d\n", log_info.btag, WSTOPSIG(status));
+        do_log_line(&log_info, tmpbuf);
+      }
+    }
+
+err_waitpid:
+err_poll:
+    if (log_target & LOG_FILE) {
+        fclose(log_info.fp); /* Also closes underlying fd */
+    }
+    if (abbreviated) {
+        free_abbr_buf(&log_info.a_buf);
+    }
+    return rc;
+}
+
+static void child(int argc, char* argv[]) {
+    // create null terminated argv_child array
+    char* argv_child[argc + 1];
+    memcpy(argv_child, argv, argc * sizeof(char *));
+    argv_child[argc] = NULL;
+
+    if (execvp(argv_child[0], argv_child)) {
+        FATAL_CHILD("executing %s failed: %s\n", argv_child[0],
+                strerror(errno));
+    }
+}
+
+int android_fork_execvp_ext(int argc, char* argv[], int *status, bool ignore_int_quit,
+        int log_target, bool abbreviated, char *file_path) {
+    pid_t pid;
+    int parent_ptty;
+    int child_ptty;
+    char *child_devname = NULL;
+    struct sigaction intact;
+    struct sigaction quitact;
+    sigset_t blockset;
+    sigset_t oldset;
+    int rc = 0;
+
+    rc = pthread_mutex_lock(&fd_mutex);
+    if (rc) {
+        ERROR("failed to lock signal_fd mutex\n");
+        goto err_lock;
+    }
+
+    /* Use ptty instead of socketpair so that STDOUT is not buffered */
+    parent_ptty = open("/dev/ptmx", O_RDWR);
+    if (parent_ptty < 0) {
+        ERROR("Cannot create parent ptty\n");
+        rc = -1;
+        goto err_open;
+    }
+
+    if (grantpt(parent_ptty) || unlockpt(parent_ptty) ||
+            ((child_devname = (char*)ptsname(parent_ptty)) == 0)) {
+        ERROR("Problem with /dev/ptmx\n");
+        rc = -1;
+        goto err_ptty;
+    }
+
+    child_ptty = open(child_devname, O_RDWR);
+    if (child_ptty < 0) {
+        ERROR("Cannot open child_ptty\n");
+        rc = -1;
+        goto err_child_ptty;
+    }
+
+    sigemptyset(&blockset);
+    sigaddset(&blockset, SIGINT);
+    sigaddset(&blockset, SIGQUIT);
+    pthread_sigmask(SIG_BLOCK, &blockset, &oldset);
+
+    pid = fork();
+    if (pid < 0) {
+        close(child_ptty);
+        ERROR("Failed to fork\n");
+        rc = -1;
+        goto err_fork;
+    } else if (pid == 0) {
+        pthread_mutex_unlock(&fd_mutex);
+        pthread_sigmask(SIG_SETMASK, &oldset, NULL);
+        close(parent_ptty);
+
+        // redirect stdout and stderr
+        dup2(child_ptty, 1);
+        dup2(child_ptty, 2);
+        close(child_ptty);
+
+        child(argc, argv);
+    } else {
+        close(child_ptty);
+        if (ignore_int_quit) {
+            struct sigaction ignact;
+
+            memset(&ignact, 0, sizeof(ignact));
+            ignact.sa_handler = SIG_IGN;
+            sigaction(SIGINT, &ignact, &intact);
+            sigaction(SIGQUIT, &ignact, &quitact);
+        }
+
+        rc = parent(argv[0], parent_ptty, pid, status, log_target,
+                    abbreviated, file_path);
+    }
+
+    if (ignore_int_quit) {
+        sigaction(SIGINT, &intact, NULL);
+        sigaction(SIGQUIT, &quitact, NULL);
+    }
+err_fork:
+    pthread_sigmask(SIG_SETMASK, &oldset, NULL);
+err_child_ptty:
+err_ptty:
+    close(parent_ptty);
+err_open:
+    pthread_mutex_unlock(&fd_mutex);
+err_lock:
+    return rc;
+}