[CodeCritique] Criticize my Linked List

I have implemented linked lists in C as a learning exercise.  I'm a noob ass so tell me how my implementation sucks and I will fix it.  I didn't have a particular use-case in mind when I wrote it.

Header:
// llist.h
#ifndef LLIST_H_
#define LLIST_H_

struct LList;
typedef struct LList LList;

struct LLNode;
typedef struct LLNode LLNode;

struct LList {
    LLNode *front, *back;
};

struct LLNode {
    void *data;
    LLNode *next;
};

LList* llist_new(LList **self);
void llist_add(LList *self, void *v);
void llist_remove(LList *self, LLNode *node);
void llist_insert(LLNode *node, void *v);
void llist_destroy(LList *self);

#endif

C file:
// llist.c
#include <assert.h>
#include <stdlib.h>

#include "llist.h"

// Initialize a new, empty LList, in dynamically allocated memory.
LList *llist_new(LList **self) {
    *self = malloc(sizeof (LList));
    if (self == NULL) { return NULL; }

    (*self)->front = NULL;
    (*self)->back = NULL;

    return *self;
}


// Append a value to the LList.  Creates a new node.
void llist_add(LList *self, void *v) {
    LLNode *node = malloc(sizeof (LLNode));
    assert(node != NULL);

    node->data = v;
    node->next = NULL;

    // Put this node at the back of the list.
    if (self->front != NULL) {
        self->back->next = node;
        self->back = node;
    } else {
        self->back = node;
        self->front = node;
    }
}


// Iterate over the LList to locate a node, and then remove it from the list.
void llist_remove(LList *self, LLNode *node) {
    LLNode *iter_node = self->front;
    LLNode *prev_node = NULL;

    while (iter_node != NULL) {
        if (iter_node == node) {
            if (prev_node != NULL) { prev_node->next = iter_node->next; }
            else { self->front = NULL; }
            free(iter_node);
            return;
        }
        prev_node = iter_node;
        iter_node = iter_node->next;
    }

}


// Insert a value after a particular node.
void llist_insert(LLNode *node, void *v) {
    LLNode *next = node->next;
    LLNode *new_node = malloc(sizeof (LLNode));
   
    new_node->data = v;
    new_node->next = next;
   
    node->next = new_node;
}


void llist_destroy(LList *self) {
    LLNode *iter_node = self->front;

    while (iter_node != NULL) {
        LLNode *next = iter_node->next;
        free(iter_node);
        iter_node = next;
    }

    free(self);
}

Testcase:
// llist_test.c
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "llist.h"

#ifdef _WIN32
char *strdup(char *s);
#endif

int main(void) {
    LList *phone_nums;
    LLNode *iter;

    if (llist_new(&phone_nums) == NULL) { printf("Out of memory."); exit(1); }
    llist_add(phone_nums, strdup("123-4567")); // Yes, I should free() these later...
    llist_add(phone_nums, strdup("890-1234"));
    llist_add(phone_nums, strdup("567-8901"));
    llist_add(phone_nums, strdup("234-5678"));
       
        LLNode *temp = NULL;
    iter = phone_nums->front;
    while (iter) {
        printf("%s\n", (char*)iter->data);
        if (!strcmp("890-1234", (char*)iter->data)) { temp = iter; }
        iter = iter->next;
    }
    puts("");
   
    llist_insert(temp, strdup("BEEP BOOP"));
   
    iter = phone_nums->front;
    while (iter) {
        printf("%s\n", (char*)iter->data);
        if (!strcmp("567-8901", (char*)iter->data)) { temp = iter; }
        iter = iter->next;
    }
    puts("");
   
    llist_remove(phone_nums, temp);
   
    iter = phone_nums->front;
    while (iter) {
        printf("%s\n", (char*)iter->data);
        if (!strcmp("567-8901", (char*)iter->data)) { temp = iter; }
        iter = iter->next;
    }
   
   
    llist_destroy(phone_nums);
    return 0;
}

#ifdef _WIN32
char *strdup(char *s) {
        char *p = malloc(strlen(s) + 1);
        strcpy(p, s);
        return p;
}
#endif

>>13
Then you're a fucking moron, holy shit, please don't have children but if you do please put them up for adoption as it is probably against the Geneva convention to have someone as retarded as you raise children you're dumber than the African Americans who shoot each other over gang colors in South Central holy shit are you fucking kidding me how can you not realize something that simple why don't you write out every sizeof as well then holy shit in fact why don't you just expand every macro while programming let me guess you're the type who writes 1 instead of sizeof(char) just because it says it's always 1 in the standard well I got news for you mister you are a fucking dickhead please never write code or post again, actually please kill yourself we don't need more fast food burger flippers posting on this board go play with some fucking barbie dolls you fucking mental midget go suck a fat cock you fucking bitch seriously FUCK OFF FAGGOT.